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  1. Intracranial pressure monitoring

    Science.gov (United States)

    ICP monitoring; CSF pressure monitoring ... There are 3 ways to monitor pressure in the skull (intracranial pressure). INTRAVENTRICULAR CATHETER The intraventricular catheter is the most accurate monitoring method. To insert an intraventricular catheter, a ...

  2. IIH with normal CSF pressures?

    Directory of Open Access Journals (Sweden)

    Soh Youn Suh

    2013-01-01

    Full Text Available Idiopathic intracranial hypertension (IIH is a condition of raised intracranial pressure (ICP in the absence of space occupying lesions. ICP is usually measured by lumbar puncture and a cerebrospinal fluid (CSF pressure above 250 mm H 2 O is one of the diagnostic criteria of IIH. Recently, we have encountered two patients who complained of headaches and exhibited disc swelling without an increased ICP. We prescribed acetazolamide and followed both patients frequently; because of the definite disc swelling with IIH related symptoms. Symptoms and signs resolved in both patients after they started taking acetazolamide. It is generally known that an elevated ICP, as measured by lumbar puncture, is the most important diagnostic sign of IIH. However, these cases caution even when CSF pressure is within the normal range, that suspicion should be raised when a patient has papilledema with related symptoms, since untreated papilledema may cause progressive and irreversible visual loss.

  3. Epidural blood patch for refractory low CSF pressure headache

    DEFF Research Database (Denmark)

    Madsen, Søren Aalbæk; Fomsgaard, Jonna Storm; Jensen, Rigmor

    2011-01-01

    of non-invasive/conservative measures and invasive measures with epidural blood patch providing the cornerstone of the invasive measures. In the present pilot study we therefore aimed to evaluate the treatment efficacy of epidural blood patch (EBP) in treatment-refractory low-pressure headache. Our...... reduction in frequency. An increase in days with use of medication was found. Increased awareness of low CSF pressure headache is emphasized and a controlled larger randomized study is needed to confirm the results. However the present results, allows us to conclude that EBP in treatment-refractory low CSF......Once believed an exceedingly rare disorder, recent evidence suggests that low cerebrospinal fluid (CSF) pressure headache has to be considered an important cause of new daily persistent headaches, particularly among young and middle-aged individuals. Treatment of low CSF pressure headache consists...

  4. Epidural blood patch for refractory low CSF pressure headache

    DEFF Research Database (Denmark)

    Madsen, Søren Aalbæk; Fomsgaard, Jonna Storm; Jensen, Rigmor

    2011-01-01

    of non-invasive/conservative measures and invasive measures with epidural blood patch providing the cornerstone of the invasive measures. In the present pilot study we therefore aimed to evaluate the treatment efficacy of epidural blood patch (EBP) in treatment-refractory low-pressure headache. Our......Once believed an exceedingly rare disorder, recent evidence suggests that low cerebrospinal fluid (CSF) pressure headache has to be considered an important cause of new daily persistent headaches, particularly among young and middle-aged individuals. Treatment of low CSF pressure headache consists...... reduction in frequency. An increase in days with use of medication was found. Increased awareness of low CSF pressure headache is emphasized and a controlled larger randomized study is needed to confirm the results. However the present results, allows us to conclude that EBP in treatment-refractory low CSF...

  5. INTRACRANIAL PRESSURE MONITORING

    Directory of Open Access Journals (Sweden)

    Retno Widiyanthi

    2013-07-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Intracranial pressure is total of pressure that is produced by brain, blood, and cerebrospinal fluid/CSF in the tight cranial space. As a respon to intracranial pressure increasing, compensation begin by movement of CSF from ventricle to cerebral subarachnoidal space, and increase the absorption of CSF. Increasing of ICP usually caused by increasing of brain volume (cerebral oedem, blood (intracranial bleeding, space occupying lesion, or CSF (hidrocephalus. Indication in ICP monitoring can be seen from : neurological criteria, abnormal CT-scan result when admission, normal CT-scan result, but had more two risk factors. According to the procedure that must be done, there are two methods in ICP monitoring: invasive ICP monitoring methodes and non-invasive measuring method. Increasing of ICP will decrease the compliance of brain, pulsation of artery more clearly, and the component of vein is lost. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}

  6. CSF monoamine metabolites, cholinesterases and lactate in the adult hydrocephalus syndrome (normal pressure hydrocephalus) related to CSF hydrodynamic parameters.

    Science.gov (United States)

    Malm, J; Kristensen, B; Ekstedt, J; Adolfsson, R; Wester, P

    1991-03-01

    Monoamine metabolites, cholinesterases and lactic acid in lumbar cerebrospinal fluid (CSF) were investigated on patients with the adult hydrocephalus syndrome (idiopathic normal pressure syndrome; AHS, n = 15), Alzheimer's disease (AD, n = 14), multi-infarct dementia (MID, n = 13) and controls (n = 21). Patients had clinical and CSF hydrodynamic investigations. Monoamine concentrations were determined by reversed-phase liquid chromatography, cholinesterases and lactate were determined photometrically. In the AHS patients, CSF monoamine concentrations were not significantly different compared with controls, AD or MID patients. AHS and AD patients showed a similar reduction of CSF acetylcholinesterase activity compared with controls. Positive correlations were found in concentrations of CSF homovanillic acid, CSF 5-hydroxyindoleacetic acid and CSF lactic acid versus CSF outflow conductance (that is, resistance against CSF outflow) in the AHS patients. A similar pattern was observed in a subgroup of MID patients characterised by dilated ventricles and disturbed CSF hydrodynamics. These data suggest that a low CSF outflow conductance may facilitate the clearance of acidic substances from the arachnoid space at the probenecid sensitive active transport site. Alternative explanations would be that a pathologically low CSF outflow conductance is accompanied by an inverse caudorostral flow of CSF or a compromised trans-ependymal diffusion.

  7. Cine-MR imaging aqueductal CSF flow in normal pressure hydrocephalus syndrome before and after CSF shunt

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    Mascalchi, M. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy)); Arnetoli, G. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy)); Inzitari, D. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy)); Dal Pozzo, G. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy)); Lolli, F. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy)); Caramella, D. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy)); Bartolozzi, C. (Sezione di Radiodiagnostica, Dipt. di Fisiopatologia Clinica, and Dipt. di Scienze Neurologiche, Florence Univ. (Italy))

    1993-11-01

    Reproducibility of the aqueductal CSF signal intensity on a gradient echo cine-MR sequence exploiting through plane inflow enhancement was tested in 11 patients with normal or dilated ventricles. Seven patients with normal pressure hydrocephalus (NPH) syndrome were investigated with the sequence before and after CSF shunting. Two patients exhibiting central flow void within a hyperintense aqueductal CSF improved after surgery and the flow void disappeared after shunting. One patient with increased maximum and minimum aqueductal CSF signal as compared to 18 healthy controls also improved and the aqueductal CSF signal was considerably decreased after shunting. Three patients with aqueductal CSF values similar to those in the controls did not improve, notwithstanding their maximum aqueductal CSF signals decreasing slightly after shunting. No appreciable aqueductal CSF flow related enhancement consistent with non-communicating hydrocephalus was found in the last NPH patient who improved after surgery. Cine-MR with inflow technique yields a reproducible evaluation of flow-related aqueductal CSF signal changes which might help in identifying shunt responsive NPH patients. These are likely to be those with hyperdynamic aqueductal CSF or aqueductal obstruction. (orig.).

  8. Conductance to outflow of CSF in normal pressure hydrocephalus.

    Science.gov (United States)

    Børgesen, S E

    1984-01-01

    Normal pressure hydrocephalus (NPH) is defined as a combination of dementia, gait disturbances and/or urinary incontinence, hydrocephalus, and a normal intracranial mean pressure. The clinical effect of CSF shunting in patients with this syndrome is sometimes striking, but generally only 50-60% of the shunted patients benefit from the treatment. It is assumed that the condition is caused by reduced conductance to outflow of CSF ( Cout ). A clinically usable method for the measurement of Cout has been developed. Cout has been measured in 80 patients with NPH. The results of clinical examination, computed tomography (CT), long-term intracranial pressure recording, isotope cisternography (ICG), and Cout have been compared to the clinical results of shunting 3 and 12 months after operation. Among the preoperative investigations Cout proved to have the best diagnostic specificity and sensitivity. Thus, selection of patients for shunting on the basis of Cout should lead to a satisfyingly high success rate. The different methods for measurement of Cout are discussed, and a theory on the pathophysiology of NPH is proposed. A clinical investigational programme, based on the results from clinical examination, CT, pressure recording, and measurements of Cout is suggested.

  9. The European iNPH Multicentre Study on the predictive values of resistance to CSF outflow and the CSF Tap Test in patients with idiopathic normal pressure hydrocephalus

    DEFF Research Database (Denmark)

    Wikkelsø, Carsten; Hellström, Per; Klinge, Petra Margarete

    2013-01-01

    The objective was to determine the sensitivity, specificity, and positive and negative predictive values of the CSF Tap Test (CSF TT) and resistance to CSF outflow (Rout) for the outcome of shunting in a sample of patients with idiopathic normal pressure hydrocephalus (iNPH).......The objective was to determine the sensitivity, specificity, and positive and negative predictive values of the CSF Tap Test (CSF TT) and resistance to CSF outflow (Rout) for the outcome of shunting in a sample of patients with idiopathic normal pressure hydrocephalus (iNPH)....

  10. CSF Flow in the Brain in the Context of Normal Pressure Hydrocephalus.

    Science.gov (United States)

    Bradley, W G

    2015-05-01

    CSF normally flows back and forth through the aqueduct during the cardiac cycle. During systole, the brain and intracranial vasculature expand and compress the lateral and third ventricles, forcing CSF craniocaudad. During diastole, they contract and flow through the aqueduct reverses. Hyperdynamic CSF flow through the aqueduct is seen when there is ventricular enlargement without cerebral atrophy. Therefore, patients presenting with clinical normal pressure hydrocephalus who have hyperdynamic CSF flow have been found to respond better to ventriculoperitoneal shunting than those with normal or decreased CSF flow. Patients with normal pressure hydrocephalus have also been found to have larger intracranial volumes than sex-matched controls, suggesting that they may have had benign external hydrocephalus as infants. While their arachnoidal granulations clearly have decreased CSF resorptive capacity, it now appears that this is fixed and that the arachnoidal granulations are not merely immature. Such patients appear to develop a parallel pathway for CSF to exit the ventricles through the extracellular space of the brain and the venous side of the glymphatic system. This pathway remains functional until late adulthood when the patient develops deep white matter ischemia, which is characterized histologically by myelin pallor (ie, loss of lipid). The attraction between the bare myelin protein and the CSF increases resistance to the extracellular outflow of CSF, causing it to back up, resulting in hydrocephalus. Thus idiopathic normal pressure hydrocephalus appears to be a "2 hit" disease: benign external hydrocephalus in infancy followed by deep white matter ischemia in late adulthood.

  11. Organic electronics based pressure sensor towards intracranial pressure monitoring

    Science.gov (United States)

    Rai, Pratyush; Varadan, Vijay K.

    2010-04-01

    The intra-cranial space, which houses the brain, contains cerebrospinal fluid (CSF) that acts as a fluid suspension medium for the brain. The CSF is always in circulation, is secreted in the cranium and is drained out through ducts called epidural veins. The venous drainage system has inherent resistance to the flow. Pressure is developed inside the cranium, which is similar to a rigid compartment. Normally a pressure of 5-15 mm Hg, in excess of atmospheric pressure, is observed at different locations inside the cranium. Increase in Intra-Cranial Pressure (ICP) can be caused by change in CSF volume caused by cerebral tumors, meningitis, by edema of a head injury or diseases related to cerebral atrophy. Hence, efficient ways of monitoring ICP need to be developed. A sensor system and monitoring scheme has been discussed here. The system architecture consists of a membrane less piezoelectric pressure sensitive element, organic thin film transistor (OTFT) based signal transduction, and signal telemetry. The components were fabricated on flexible substrate and have been assembled using flip-chip packaging technology. Material science and fabrication processes, subjective to the device performance, have been discussed. Capability of the device in detecting pressure variation, within the ICP pressure range, is investigated and applicability of measurement scheme to medical conditions has been argued for. Also, applications of such a sensor-OTFT assembly for logic sensor switching and patient specific-secure monitoring system have been discussed.

  12. Comparison of CSF Distribution between Idiopathic Normal Pressure Hydrocephalus and Alzheimer Disease.

    Science.gov (United States)

    Yamada, S; Ishikawa, M; Yamamoto, K

    2016-07-01

    CSF volumes in the basal cistern and Sylvian fissure are increased in both idiopathic normal pressure hydrocephalus and Alzheimer disease, though the differences in these volumes in idiopathic normal pressure hydrocephalus and Alzheimer disease have not been well-described. Using CSF segmentation and volume quantification, we compared the distribution of CSF in idiopathic normal pressure hydrocephalus and Alzheimer disease. CSF volumes were extracted from T2-weighted 3D spin-echo sequences on 3T MR imaging and quantified semi-automatically. We compared the volumes and ratios of the ventricles and subarachnoid spaces after classification in 30 patients diagnosed with idiopathic normal pressure hydrocephalus, 10 with concurrent idiopathic normal pressure hydrocephalus and Alzheimer disease, 18 with Alzheimer disease, and 26 control subjects 60 years of age or older. Brain to ventricle ratios at the anterior and posterior commissure levels and 3D volumetric convexity cistern to ventricle ratios were useful indices for the differential diagnosis of idiopathic normal pressure hydrocephalus or idiopathic normal pressure hydrocephalus with Alzheimer disease from Alzheimer disease, similar to the z-Evans index and callosal angle. The most distinctive characteristics of the CSF distribution in idiopathic normal pressure hydrocephalus were small convexity subarachnoid spaces and the large volume of the basal cistern and Sylvian fissure. The distribution of the subarachnoid spaces in the idiopathic normal pressure hydrocephalus with Alzheimer disease group was the most deformed among these 3 groups, though the mean ventricular volume of the idiopathic normal pressure hydrocephalus with Alzheimer disease group was intermediate between that of the idiopathic normal pressure hydrocephalus and Alzheimer disease groups. The z-axial expansion of the lateral ventricle and compression of the brain just above the ventricle were the common findings in the parameters for differentiating

  13. Frequency analyses of CSF flow on cine MRI in normal pressure hydrocephalus

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    Miyati, Tosiaki; Kasuga, Toshio; Koshida, Kichiro; Sanada, Shigeru; Onoguchi, Masahisa [Department of Radiological Technology, School of Health Sciences, Faculty of Medicine, Kanazawa University, 5-11-80, Kodatsuno, Kanazawa, Ishikawa 920-0942 (Japan); Mase, Mitsuhito; Yamada, Kazuo [Department of Neurosurgery, Nagoya City University Medical School, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi 467-8602 (Japan); Banno, Tatsuo [Department of Central Radiology, Nagoya City University Hospital, 1 Kawasumi, Mizuho-cho, Mizuho-ku, Nagoya, Aichi 467-8602 (Japan); Fujita, Hiroshi [Department of Information Science, Faculty of Engineering, Gifu University, Yanagido 1-1, Gifu 501-1193 (Japan)

    2003-05-01

    Our objective was to clarify intracranial cerebrospinal fluid (CSF) flow dynamics in normal-pressure hydrocephalus (NPH). Frequency analyses of CSF flow measured with phase-contrast cine MRI were performed. The CSF flow spectra in the aqueduct were determined in patients (n=51) with NPH, brain atrophy or asymptomatic ventricular dilation (VD), and in healthy volunteers (control group; n=25). The changes in CSF flow spectra were also analyzed after intravenous injection of acetazolamide. Moreover, a phase transfer function (PTF) calculated from the spectra of the driving vascular pulsation and CSF flow in the aqueduct were assessed. These values were compared with the pressure volume response (PVR). The amplitude in the NPH group was significantly larger than that in the VD or control group because of a decrease in compliance. The phase in the NPH group was significantly different from that in either the VD or the control group, but no difference was found between the VD and control groups. The amplitude increased in all groups after acetazolamide injection. The PTF in the NPH group was significantly larger than in the control group, and a positive correlation was noted between PTF and PVR. Frequency analyses of CSF flow measured by cine MRI make it possible to noninvasively obtain a more detailed picture of the pathophysiology of NPH. (orig.)

  14. Isotope cisternography and conductance to outflow of CSF in normal pressure hydrocephalus.

    Science.gov (United States)

    Børgesen, S E; Westergård, L; Gjerris, F

    1981-01-01

    In 50 patients with normal pressure hydrocephalus (NPH) the findings on lumbar isotope cisternography (IGG) were compared to the conductance to outflow of CSF (Cout) as measured by lumbo-ventricular perfusion. The purpose was to identify those ICG-characteristics that imply a low Cout and thus may indicate CSF shunting therapy. Normal ICG was found only in three patients, where Cout was not, or only moderately, decreased. There was a significant correlation between a low Cout and occurrence of ventricular retention and absent parasagittal accumulation at 24 hours or later, following injection. These findings may, however, also be present in patients with no, or only moderate, decreased Cout, where CSF shunting may seen unjustified. It is concluded, that the indication for CSF shunting cannot be based on the results of ICG alone.

  15. Furosemide lowers intracranial pressure by inhibiting CSF production.

    Science.gov (United States)

    Lorenzo, A V; Hornig, G; Zavala, L M; Boss, V; Welch, K

    1986-12-01

    Furosemide administration effectively lowers intracranial pressure in newborn preterm and term rabbit pups. This effect may be due to the diuretic action of the drug, its ability to inhibit cerebrospinal fluid production or to a combination of both. To test these possibilities newborn rabbits were either injected with furosemide and left unmolested for 6 hours, or anaesthetized and subjected to ventriculocisternal perfusions. During the 6 hour postnatal period the decrease in body weight was 8 times greater in furosemide than in saline treated pups. However, no difference was noted between the average brain weights of these two groups. Secondary effects of the diuretic were noted in blood (12.5% increase in the haematocrit over control value) and in muscle in which tissue water content and NA+ concentration were decreased while K+ concentration was increased. The fact that these parameters remained unchanged in brain suggests that the lowering of intracranial pressure was not attributable to the secondary effects of the diuretic agent. However, the marked reduction in cerebrospinal production noted following furosemide administration indicates that in newborn rabbits this may represent the primary mechanism by which furosemide lowers intracranial pressure.

  16. Home monitoring of blood pressure

    OpenAIRE

    McGrath, Barry P.

    2015-01-01

    Home blood pressure monitoring is the self-measurement of blood pressure by patients. In the diagnosis and management of high blood pressure it is complementary to 24-hour ambulatory blood pressure monitoring and clinic blood pressure measurements. Home monitoring can also help to identify white-coat and masked hypertension.

  17. DIGITAL BLOOD PRESSURE MONITOR

    Directory of Open Access Journals (Sweden)

    R. Fuentes

    2004-12-01

    Full Text Available In this work we present a blood pressure monitor which measures both the high blood pressure (systolic pressure,and the low blood pressure (diastolic pressure. It is a semiautomatic meter because the inflation of the occlusivecuff is carried out in a manual way. The transducer used is a piezoresistive silicon pressure sensor integrated onchip which provides a proportional voltage to the input pressure, with a measurement range from 0 to 50 kPa (0–7.3 PSI. The oscillometric method is employed, which consists on detecting the oscillometric signal on brachialartery, being processed at each pressure step, when the cuff is gradually deflated. Signal sampling is carried out ata rate determined by the heart rate.In order to program the digital electronics of the circuit we used Altera tools, with the compiler MAX-PLUS II, andthe device selected to implement the design was an EPM7128SLC84-15 CPLD (Complex Programmable LogicDevice

  18. Frequency analysis of CSF flow on cine-MRI in normal pressure hydrocephalus

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    Miyati, Tosiaki; Kasuga, Toshio; Imai, Hiroshi [Kanazawa Univ. (Japan). School of Medicine; Fujita, Hiroshi; Mase, Mitsuhito; Itikawa, Katuhiro

    2001-09-01

    To clarify the flow dynamics of intracranial cerebrospinal fluid (CSF) in normal pressure hydrocephalus (NPH), frequency analyses of CSF flow measured with an ECG-gated phase contrast cine magnetic resonance imaging (MRI) were performed. The amplitude and phase in the CSF flow spectra in the aqueduct were determined in patients with NPH after a subarachnoid hemorrhage (SAH-NPH group, n=26), an idiopathic NPH (I-NPH group, n=4), an asymptomatic ventricular dilation or a brain atrophy (VD group, n=21), and in healthy volunteers (control group, n=25). The changes of CSF flow spectra were also analyzed 5 and 15 minutes after an intravenous injection of acetazolamide. Moreover, a phase transfer function (PTF) calculated from the spectra of the driving vascular pulsation and CSF flow in the aqueduct were assessed in patients with SAH-NPH and control groups before and after acetazolamide injection. There values were compared with the pressure volume response (PVR). The amplitude of the 1st-3rd harmonics in the SAH-NPH or I-NPH group was significantly larger than in the control or VD group because of a decrease in compliance (increase in PVR). The phase of the 1st harmonic in the SAH-NPH group was significantly different from that in the control or VD group, but no difference was found between the control and VD groups. The amplitude of the 0-3rd harmonics increased, and the phase of the 1st harmonic changed in all groups after an acetazolamide injection. An evaluation of the time course of the direct current of CSF flow provided further information about the compensatory faculty of the cerebrospinal cavity. A PTF of the 1st harmonic in the SAH-NPH group was significantly larger than in the control group, and a positive correlation was noted between PTF of the 1st harmonic and PVR. In conclusion, frequency analyses of CSF flow measured by cine-MRI make it possible to obtain noninvasively a more detailed picture of the pathophysiology of NPH and of changes in intracranial

  19. INTRACRANIAL PRESSURE MONITORING TECHNIQUE

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    Ida Bagus Adi Kayana

    2013-03-01

    Full Text Available Head injury is the most significant cause of increased morbidity and mortality. An estimated 1.4 million head injuries occur each year, with and more than 1.1 million come to the Emergency Unit. On each patient head injury, an increase in intracranial pressure (ICP related to poor outcomes and aggressive therapy to increased ICP can improve the outcomes. ICP monitoring is the most widely used because of the prevention and control of ICP as well as maintain the pressure increase perfusion of cerebral (Cerebral Perfusion Pressure/CPP is the basic purpose of handling head injury. There are two methods of monitoring ICP that is an invasive methods (directly and non-invasive techniques (indirectly. The method commonly used, namely intraventricular and intraparenkimal (microtransducer sensor because it is more accurate but keep attention to the existence of the risk of bleeding and infection resulting from installation. Monitoring of ICT can determine the actions that avoid further brain injury, which can be lethal and irreversibel.

  20. Computed tomography and pneumoencephalography compared to conductance to outflow of CSF in normal pressure hydrocephalus

    Energy Technology Data Exchange (ETDEWEB)

    Borgesen, S.E.; Gyldensted, C.; Gjerris, F.; Lester, J.

    1980-08-01

    The conductance to outflow of CSF (Csub(out)) was measured in 66 patients with normal pressure hydrocephalus (NPH). All patients were investigated with computed tomography (CT); 34 of the patients also had pneumoencephalography (PEG). Periventricular hypodensity on CT indicates a low Csub(out). Cortical sulci smaller than 1.9 mm on CT indicate a low Csub(out), while wide cortical sulci do not exclude a low Csub(out). There was a good correlation between ventricular size on CT and PEG, but the ventricular size is unrelated to Csub(out). No findings on PEG indicate a low Csub(out).

  1. Computed tomography and pneumoencephalography compared to conductance to outflow of CSF in normal pressure hydrocephalus.

    Science.gov (United States)

    Børgesen, S E; Gyldensted, C; Gjerris, F; Lester, J

    1980-08-01

    The conductance to outflow of CSF (Cout) was measured in 66 patients with normal pressure hydrocephalus (NPH). All patients were investigated with computed tomography (CT); 34 of the patients also had pneumoencephalography (PEG). Periventricular hypodensity on CT indicates a low Cout. Cortical sulci smaller than 1.9 mm on CT indicate a low Cout, while wide cortical sulci do not exclude a low Cout. There was a good correlation between ventricular size on CT and PEG, but the ventricular size is unrelated to Cout. No findings on PEG indicate a low Cout.

  2. Intracranial Pressure Monitoring

    DEFF Research Database (Denmark)

    Raboel, P H; Bartek, J; Andresen, M;

    2012-01-01

    Monitoring of intracranial pressure (ICP) has been used for decades in the fields of neurosurgery and neurology. There are multiple techniques: invasive as well as noninvasive. This paper aims to provide an overview of the advantages and disadvantages of the most common and well-known methods as ......-invasive techniques are without the invasive methods' risk of complication, but fail to measure ICP accurately enough to be used as routine alternatives to invasive measurement. We conclude that invasive measurement is currently the only option for accurate measurement of ICP....... as well as assess whether noninvasive techniques (transcranial Doppler, tympanic membrane displacement, optic nerve sheath diameter, CT scan/MRI and fundoscopy) can be used as reliable alternatives to the invasive techniques (ventriculostomy and microtransducers). Ventriculostomy is considered the gold...

  3. The predictive value of conductance to outflow of CSF in normal pressure hydrocephalus.

    Science.gov (United States)

    Børgesen, S E; Gjerris, F

    1982-03-01

    Conductance to outflow of CSF was measured in a prospective study of 80 patients with normal pressure hydrocephalus. Measured outflow was compared with clinical findings, computed tomography, intracranial pressure measurements and with the results of shunting. Follow-up time was one year. Outflow measurements predicted the outcome of shunting in 96 per cent of the patients. Patients with the combination of known aetiology, short history, gait disturbances, severe dementia, urinary incontinence and hydrocephalus on CT can be shunted without further investigations. Periventricular hypodensity on CT scanning predicts an excellent result for shunting. Based on results of preoperative investigations and outcome of shunting we propose a programme for the investigation of future patients with normal pressure hydrocephalus.

  4. Blood pressure monitors for home

    Science.gov (United States)

    ... page: //medlineplus.gov/ency/article/007482.htm Blood pressure monitors for home To use the sharing features ... ask you to keep track of your blood pressure at home. To do this, you will need ...

  5. Indications for CSF shunting in normal pressure hydrocephalus following subarachnoid hemorrhage with lateral ventricular size change on cine-MR

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    Fujitsuka, Mitsuyuki [Kyorin Univ., Mitaka, Tokyo (Japan). School of Medicine

    2002-09-01

    To clarify the indications for cerebrospinal fluid (CSF) shunting in normal pressure hydrocephalus (NPH) following subarachnoid hemorrhage (SAH), the author investigated changes in the pulsatile brain motions during a cardiac cycle in 17 cases with ventriculomegaly following SAH on cardiac gated cine MR images comparing with those in 50 normal adults. In 15 of these seventeen cases, the lateral ventricles not only constricted immediately following the R-wave related to brain expansion but also expanded paradoxically over the initial size during a cardiac diastole. These patterns were different from those of normal adults, and eleven of them showed excellent response to CSF shunting. Theses findings in ventricular motion during a cardiac cycle indicate that the forceful intraventricular CSF flows and stagnancy expand the ventricular walls causing compression of the surrounding brain against the skull. In the remaining two, the lateral ventricles only constricted immediately following the R-wave and the ventricular size change was similar to those of normal adults, and they were diagnosed as not requiring CSF shunting. Assessing ventricular size change on cine-MR enables non-invasive differentiation of NPH from other form of ventriculomegaly, and evaluation of the benefit of CSF shunting is also possible by this technique preoperatively. (author)

  6. Use of intracranial pressure monitoring in bacterial meningitis

    DEFF Research Database (Denmark)

    Larsen, Lykke; Rom Poulsen, Frantz; Nielsen, Troels H

    2017-01-01

    BACKGROUND: The aim of this study was to evaluate the clinical outcome of patients with severe bacterial meningitis where intracranial pressure (ICP) monitoring has been performed. METHODS: A retrospective observational study including patients admitted 1st(.) January 2005 to 31st(.) December 2014...... = 0.034). Lower mean-cerebral perfusion pressure (CPP) was found to correlate with adverse outcome (p = 0.005). Cerebrospinal fluid (CSF) was drained in fourteen patients. Increased ICP (>20 mmHg) was observed in twenty four patients. No significant correlation was found between measured ICP and head...

  7. Monitoring CSF proteome alterations in amyotrophic lateral sclerosis: obstacles and perspectives in translating a novel marker panel to the clinic.

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    Nils von Neuhoff

    Full Text Available BACKGROUND: Amyotrophic lateral sclerosis (ALS is a fatal disorder of the motor neuron system with poor prognosis and marginal therapeutic options. Current clinical diagnostic criteria are based on electrophysiological examination and exclusion of other ALS-mimicking conditions. Neuroprotective treatments are, however, most promising in early disease stages. Identification of disease-specific CSF biomarkers and associated biochemical pathways is therefore most relevant to monitor disease progression, response to neuroprotective agents and to enable early inclusion of patients into clinical trials. METHODS AND FINDINGS: CSF from 35 patients with ALS diagnosed according to the revised El Escorial criteria and 23 age-matched controls was processed using paramagnetic bead chromatography for protein isolation and subsequently analyzed by MALDI-TOF mass spectrometry. CSF protein profiles were integrated into a Random Forest model constructed from 153 mass peaks. After reducing this peak set to the top 25%, a classifier was built which enabled prediction of ALS with high accuracy, sensitivity and specificity. Further analysis of the identified peptides resulted in a panel of five highly sensitive ALS biomarkers. Upregulation of secreted phosphoprotein 1 in ALS-CSF samples was confirmed by univariate analysis of ELISA and mass spectrometry data. Further quantitative validation of the five biomarkers was achieved in an 80-plex Multiple Reaction Monitoring mass spectrometry assay. CONCLUSIONS: ALS classification based on the CSF biomarker panel proposed in this study could become a valuable predictive tool for early clinical risk stratification. Of the numerous CSF proteins identified, many have putative roles in ALS-related metabolic processes, particularly in chromogranin-mediated secretion signaling pathways. While a stand-alone clinical application of this classifier will only be possible after further validation and a multicenter trial, it could be

  8. Arterial Pressure Monitoring in Mice

    Science.gov (United States)

    Zhao, Xin; Ho, David; Gao, Shumin; Hong, Chull; Vatner, Dorothy E.; Vatner, Stephen F.

    2011-01-01

    The use of mice for the evaluation and study of cardiovascular pathophysiology is growing rapidly, primarily due to the relative ease for developing genetically engineered mouse models. Arterial pressure monitoring is central to the evaluation of the phenotypic changes associated with cardiovascular pathology and interventions in these transgenic and knockout models. There are four major techniques for measuring arterial pressure in the mouse: tail cuff system, implanted fluid filled catheters, Millar catheters and implanted telemetry systems. Here we provide protocols for their use and discuss the advantages and limitations for each of these techniques . PMID:21686061

  9. An improved mathematical model to simulate mold filling process in high pressure die casting using CLSVOF method and CSF model

    Directory of Open Access Journals (Sweden)

    Cheng Bi

    2015-05-01

    Full Text Available A 3D mathematical model was proposed to simulate the mold filling process in high-pressure die casting (HPDC to improve accuracy considering the surface tension. Piecewise liner interface calculation (PLIC and volume of fluid (VOF methods were used to construct the pattern of the liquid interface. A coupled level-set and VOF method (CLSVOF was proposed to capture the interface pattern and obtain its normal vector. A continuum surface force (CSF model was used to consider the surface tension. Two water analogy experiments were carried out using the proposed model. Simulation and experimental results were analyzed and compared; and the effects of surface tension were also discussed. The simulation results agreed well with the experiments and the simulation accuracy was an improvement on interface geometries, liquid flows, and gas entrapments.

  10. A quantitative study of CSF pulsatile flow in normal pressure hydrocephalus; An analysis of flow patterns before and after a shunting procedure using cine MR phase imaging

    Energy Technology Data Exchange (ETDEWEB)

    Katayama, Shinji; Makabe, Tetsuo; Itoh, Takahiko (Okayama Univ. (Japan). School of Medicine) (and others)

    1992-06-01

    In the previous report, we described the visualization and quantitative analysis of a normal CSF pulsatile flow using cine MR phase imaging. In the present study, CSF flow velocities were measured in patients with normal pressure hydrocephalus (NPH) before and after a shunting procedure. All of the healthy subjects showed a similar flow pattern in the time-velocity flow profiles (TVFP). However, patients with NPH showed a variable pattern of TVFP and could be divided into the following four types: Type 0: the CSF flow pattern was similar to that of the healthy subjects. Type I: the caudal peak flow was delayed more than 190 msec on TVFP. Type II: the caudal peak flow was not apparent, but the CSF flow through the aqueduct was remarkable on phase images. Type III: the amplitude of TVFP was very small, and no CSF flow through the aqueduct was identified. The patients with Type III TVFP showed significantly lower NPH scores. The lumbar CSF pressures tended to be high in the patients with Type III TVFP, but nevertheless failed to reach a statistically significant level. The amplitude of TVFP increased in the patients who improved clinically after the shunting procedure. Some of the Type III patients changed into Type II, I, and 0; also, one of the Type II patients changed into a Type I patients after the shunting procedure. We conclude that cine MR phase imaging is useful for analyzing the CSF flow of the patients with NPH before and after the shunting procedure as well as for evaluating shunt patency. (author).

  11. Ashcroft Pressure Switch Monitor for Low SCHe Purge Pressure

    Energy Technology Data Exchange (ETDEWEB)

    VAN KATWIJK, C.

    2000-06-21

    These 0-15 psig pressure switches are located in the SCHe helium purge lines after PCV-5*23 and before PCV-5*27. The pressure switches monitor the pressure being maintained between the two PCVs and actuate on low pressure of 15 psig. This design is used for each of the SCHe supply lines (4). Electronic output signal is NON-SAFETY (GS).

  12. CSF analysis

    Science.gov (United States)

    Cerebrospinal fluid analysis ... Analysis of CSF can help detect certain conditions and diseases. All of the following can be, but ... An abnormal CSF analysis result may be due to many different causes, ... Encephalitis (such as West Nile and Eastern Equine) Hepatic ...

  13. In-house development of a dedicated data acquisition and monitoring system for intracranial pressure, patient posture and patient symptoms in a regional neurosciences centre.

    Science.gov (United States)

    Marsden, S P; Boddy, I J S; Strachan, R D; Chambers, I R

    2016-02-01

    Management of traumatic brain injury and cerebrospinal fluid (CSF) flow disorders can be aided by measurement and monitoring of intracranial pressure (ICP). In addition to pressure measurement, knowledge of patient symptoms and posture during monitoring are also valuable, particularly in the management of CSF flow disorders. ICP monitoring systems have been developed in this centre to meet clinical needs in the absence of commercially available solutions. An early system (mark I) was developed and the technical challenges in its design are described, along with limitations to this system that motivated the development of a new mark II system. The mark II system is then described.

  14. Embedded programmable blood pressure monitoring system

    Science.gov (United States)

    Hasan, Md. Mahmud-Ul; Islam, Md. Kafiul; Shawon, Mehedi Azad; Nowrin, Tasnuva Faruk

    2010-02-01

    A more efficient newer algorithm of detecting systolic and diastolic pressure of human body along with a complete package of an effective user-friendly embedded programmable blood pressure monitoring system has been proposed in this paper to reduce the overall workload of medical personals as well as to monitor patient's condition more conveniently and accurately. Available devices for measuring blood pressure have some problems and limitations in case of both analog and digital devices. The sphygmomanometer, being analog device, is still being used widely because of its reliability and accuracy over digital ones. But it requires a skilled person to measure the blood pressure and obviously not being automated as well as time consuming. Our proposed system being a microcontroller based embedded system has the advantages of the available digital blood pressure machines along with a much improved form and has higher accuracy at the same time. This system can also be interfaced with computer through serial port/USB to publish the measured blood pressure data on the LAN or internet. The device can be programmed to determine the patient's blood pressure after each certain interval of time in a graphical form. To sense the pressure of human body, a pressure to voltage transducer is used along with a cuff in our system. During the blood pressure measurement cycle, the output voltage of the transducer is taken by the built-in ADC of microcontroller after an amplifier stage. The recorded data are then processed and analyzed using the effective software routine to determine the blood pressure of the person under test. Our proposed system is thus expected to certainly enhance the existing blood pressure monitoring system by providing accuracy, time efficiency, user-friendliness and at last but not the least the 'better way of monitoring patient's blood pressure under critical care' all together at the same time.

  15. CSF Analysis

    Science.gov (United States)

    ... a chronic disease, such as multiple sclerosis or Alzheimer disease . Depending on a person's history, a healthcare provider may order CSF analysis when some combination of the following signs and symptoms appear, especially when accompanied by flu-like symptoms ...

  16. CSF leak

    Science.gov (United States)

    ... rarely). Drainage of CSF from the nose (rarely). Exams and Tests The health care provider will perform ... usually recommended. Drinking more fluids, especially drinks with caffeine, can help slow or stop the leak and ...

  17. Pressure garment design tool to monitor exerted pressures.

    Science.gov (United States)

    Macintyre, Lisa; Ferguson, Rhona

    2013-09-01

    Pressure garments are used in the treatment of hypertrophic scarring following serious burns. The use of pressure garments is believed to hasten the maturation process, reduce pruritus associated with immature hypertrophic scars and prevent the formation of contractures over flexor joints. Pressure garments are normally made to measure for individual patients from elastic fabrics and are worn continuously for up to 2 years or until scar maturation. There are 2 methods of constructing pressure garments. The most common method, called the Reduction Factor method, involves reducing the patient's circumferential measurements by a certain percentage. The second method uses the Laplace Law to calculate the dimensions of pressure garments based on the circumferential measurements of the patient and the tension profile of the fabric. The Laplace Law method is complicated to utilise manually and no design tool is currently available to aid this process. This paper presents the development and suggested use of 2 new pressure garment design tools that will aid pressure garment design using the Reduction Factor and Laplace Law methods. Both tools calculate the pressure garment dimensions and the mean pressure that will be exerted around the body at each measurement point. Monitoring the pressures exerted by pressure garments and noting the clinical outcome would enable clinicians to build an understanding of the implications of particular pressures on scar outcome, maturation times and patient compliance rates. Once the optimum pressure for particular treatments is known, the Laplace Law method described in this paper can be used to deliver those average pressures to all patients. This paper also presents the results of a small scale audit of measurements taken for the fabrication of pressure garments in two UK hospitals. This audit highlights the wide range of pressures that are exerted using the Reduction Factor method and that manual pattern 'smoothing' can dramatically

  18. Endotracheal Tube Cuff Pressure Monitoring in Children

    Directory of Open Access Journals (Sweden)

    V. V. Lazarev

    2012-01-01

    Full Text Available Objective: to estimate tracheal morphological changes in children, by using a device for the continuous monitoring and regulation of endotracheal tube cuff pressure. Subjects and methods. Two groups of children were examined. In Group A comprising 22 children aged 2 months to 16 years, the adequacy of the external control balloon palpation method was estimated to measure endotracheal tube cuff pressure. In Group B consisting of 12 children aged 5 to 18 years on mechanical ventilation for more than 3 days, the efficiency and appropriateness of applying a PressureEasy device for monitoring the pressure in the endotracheal tube cuff were assessed to prevent postintubation tracheal complications. In the latter group, the authors identified a study subgroup (BI of 8 patients where this device was employed and a control group of 4 patients (BII where it was not used. Results. Group A showed that endotracheal tube cuff pressure was 20—30 cm H2O in 31.8% of cases, greater than 30 cm H2O in 36.4%, and lower than 20 cm H2O in 31.8%. Subgroup BI displayed considerably lower macro- and microscopic histological changes than Subgroup BII. Conclusion. Determination of endotracheal tube cuff pressure by palpation of the external control balloon does not reflect its real values. The magnitude of tracheal changes is more intensive if continuous monitoring and regulation of pressure in the endotracheal tube cuff is absent. The PressureEasy device to monitor endotracheal tube cuff pressure permits its variability maintenance at a given level, by mitigating the damaging effect of the cuff on tracheal tissue. Key words: endotracheal tube, cuff, histology, ischemia, prevention, pressure, trachea.

  19. “Spontaneous” CSF Fistula due to Transtegmental Brain Herniation in Combination with Signs of Increased Intracranial Pressure and Petrous Bone Hyperpneumatization: An Illustrative Case Report

    Science.gov (United States)

    Rivera, Diones; Fermin-Delgado, Rafael; Stoeter, Peter

    2014-01-01

    Background and Importance Transtegmental brain herniation into the petrous bone is a rare cause of rhinoliquorrhea. Our case presents a combination of several typical clinical and imaging findings illustrating the ongoing etiologic discussion of such cerebrospinal fluid (CSF) fistulas. Clinical Presentation A 53-year-old man presented with nasal discharge after a strong effort to suppress coughing. Imaging revealed a transtegmental herniation of parts of the inferior temporal gyrus into the petrous bone and in addition a combination of signs of chronically increased intracranial pressure and a hyperpneumatization of the petrous bone. The fistula was closed by a middle cranial fossa approach. Conclusion The case illustrates the two main predisposing factors for development of petrous bone CSF fistulas: increased intracranial pressure and thinning of the tegmental roof due to extensive development of air cells. Because the CSF leakage repair does not change the underlying cause, patients have to be informed about the possibility of developing increased intracranial pressure and recurrences of brain herniations at other sites. PMID:25485224

  20. Monitoring cerebrovascular pressure reactivity with rheoencephalography

    Science.gov (United States)

    Brady, K. M.; Mytar, J. O.; Kibler, K. K.; Easley, R. B.; Koehler, R. C.; Czosnyka, M.; Smielewski, P.; Zweifel, C.; Bodo, M.; Pearce, F. J.; Armonda, R. A.

    2010-04-01

    Determining optimal perfusion pressure for patients with traumatic brain injury can be accomplished by monitoring the pressure reactivity index, or PRx, which requires an intracranial pressure monitor. We hypothesized that pressure reactivity could be quantified using a rheoencephalography index, or REGx. We measured the REGx and PRx as repetitive, low-frequency linear correlation between arterial blood pressure and intracranial pressure (PRx) or arterial blood pressure and REG pulse amplitude (REGx) in a piglet model of progressive hypotension. We compared the PRx and REGx against a gold standard determination of the lower limit of autoregulation using laser-Doppler measurements of cortical red cell flux. The PRx produced an accurate metric of vascular reactivity in this cohort, with area under the receiver-operator characteristic curves of 0.91. REGx was moderately correlated to the PRx, (Spearman r = 0.63, p < 0.0001; Bland-Altman bias-0.13). The area under the receiver-operator curve for the REGx was 0.86. Disagreement occurred at extremes of hypotension.

  1. Third ventriculostomy through the lamina terminalis for intracranial pressure monitoring after aneurysm surgery: technical note

    Directory of Open Access Journals (Sweden)

    Kraemer Jorge L.

    2002-01-01

    Full Text Available OBJECTIVE: A new ventriculostomy technique through the lamina terminalis is described. This technique is applied mainly during aneurysm surgery at the acute stage. METHOD: Thirteen patients were operated on intracranial aneurysms and, during the procedure, had the lamina terminalis fenestrated. A ventricular catheter was inserted into the third ventricule, left in place and connected to an external drainage system for further intracranial pressure (ICP monitoring and/or cerebrospinal fluid (CSF drainage. RESULTS: ICP readings and CSF drainage were obtained in all cases. No complication was recorded. CONCLUSION: Third ventriculostomy through the lamina terminalis is a simple and easy technique that can be used as an alternative to conventional ventriculostomy. This procedure can be indicated in cases where the ventricule is not reached by means of another technique, and when the decision to perform ventriculostomy is made at the end of aneurysm surgery.

  2. KSC inventor tests cabin pressure monitor

    Science.gov (United States)

    2000-01-01

    Jan Zysko (left) and Rich Mizell (right) test a Personal Cabin Pressure Altitude Monitor in an altitude chamber at Tyndall Air Force Base in Florida. Zysko invented the pager-sized monitor that alerts wearers of a potentially dangerous or deteriorating cabin pressure altitude condition, which can lead to life- threatening hypoxia. Zysko is chief of the KSC Spaceport Engineering and Technology directorate's data and electronic systems branch. Mizell is a Shuttle processing engineer. The monitor, which has drawn the interest of such organizations as the Federal Aviation Administration for use in commercial airliners and private aircraft, was originally designed to offer Space Shuttle and Space Station crew members added independent notification about any depressurization.

  3. Beat-to-Beat Blood Pressure Monitor

    Science.gov (United States)

    Lee, Yong Jin

    2012-01-01

    This device provides non-invasive beat-to-beat blood pressure measurements and can be worn over the upper arm for prolonged durations. Phase and waveform analyses are performed on filtered proximal and distal photoplethysmographic (PPG) waveforms obtained from the brachial artery. The phase analysis is used primarily for the computation of the mean arterial pressure, while the waveform analysis is used primarily to obtain the pulse pressure. Real-time compliance estimate is used to refine both the mean arterial and pulse pressures to provide the beat-to-beat blood pressure measurement. This wearable physiological monitor can be used to continuously observe the beat-to-beat blood pressure (B3P). It can be used to monitor the effect of prolonged exposures to reduced gravitational environments and the effectiveness of various countermeasures. A number of researchers have used pulse wave velocity (PWV) of blood in the arteries to infer the beat-to-beat blood pressure. There has been documentation of relative success, but a device that is able to provide the required accuracy and repeatability has not yet been developed. It has been demonstrated that an accurate and repeatable blood pressure measurement can be obtained by measuring the phase change (e.g., phase velocity), amplitude change, and distortion of the PPG waveforms along the brachial artery. The approach is based on comparing the full PPG waveform between two points along the artery rather than measuring the time-of-flight. Minimizing the measurement separation and confining the measurement area to a single, well-defined artery allows the waveform to retain the general shape between the two measurement points. This allows signal processing of waveforms to determine the phase and amplitude changes.

  4. Narrow CSF space at high convexity and high midline areas in idiopathic normal pressure hydrocephalus detected by axial and coronal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Makoto [Iwate Medical University, Department of Radiology, Morioka (Japan); Honda, Satoshi [St. Luke' s International Hospital, Department of Radiology, Tokyo (Japan); Yuasa, Tatsuhiko; Iwamura, Akihide [Kohnodai Hospital, National Center of Neurology and Psychiatry, Department of Neurology, Ichikawa (Japan); Shibata, Eri [Iwate Medical University, Department of Neuropsychiatry, Morioka (Japan); Ohba, Hideki [Iwate Medical University, Department of Neurology, Morioka (Japan)

    2008-02-15

    The aim of this study was to determine the performance of axial and coronal magnetic resonance imaging (MRI) in detecting the narrowing of the cerebrospinal fluid (CSF) space at the high convexity and high midline areas, which is speculated to be one of the clinical characteristics of idiopathic normal pressure hydrocephalus (iNPH). We retrospectively examined axial and coronal T1-weighted images of 14 iNPH patients and 12 age-matched controls. The narrowness of the CSF space at the high convexity/midline was blindly evaluated by five raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. Axial and coronal imaging accurately determined the presence of the narrow cisterns/sulci at the high convexity/midline and was capable of predicting probable/definite iNPH with a high degree of accuracy. there were also no significant differences in the detection of this finding between the axial and coronal images. Both axial and coronal T1-weighted MRI can detect the narrow CSF space at the high convexity/midline accurately and may therefore facilitate clinicians in choosing a management strategy for iNPH patients. (orig.)

  5. Ambulatory Blood Pressure Monitoring in the Elderly

    OpenAIRE

    Juan Diego Mediavilla García; Fernando Jaén Águila; Celia Fernández Torres; Blas Gil Extremera; Juan Jiménez Alonso

    2012-01-01

    The incidence of hypertension is high in the elderly and is present in 2/3 of the patients older than 65 years. Prevalence can reach 90% in patients older than 80 years. The presence of isolated systolic hypertension (ISH) is characteristic of this population. However, the prevalence of hypertension by ambulatory blood pressure monitoring (ABPM) is not well known. In this study, we analyzed the special characteristics of hypertension in this population, giving special emphasis on ABPM readings.

  6. Ambulatory Blood Pressure Monitoring in Clinical Practice: A Review

    OpenAIRE

    Turner, J. Rick; Viera, Anthony J.; Shimbo, Daichi

    2014-01-01

    Ambulatory blood pressure monitoring offers the ability to collect blood pressure readings several times an hour across a 24-hour period. Ambulatory blood pressure monitoring facilitates the identification of white-coat hypertension, the phenomenon whereby certain individuals who are not on antihypertensive medication show elevated blood pressure in a clinical setting but show non-elevated blood pressure averages when assessed by ambulatory blood pressure monitoring. Additionally, readings ca...

  7. Monitoring of Intracranial Pressure During Intracranial Endoscopy

    Directory of Open Access Journals (Sweden)

    Rajeev Kumar

    2013-08-01

    Full Text Available Background: Intracranial endoscopy is a minimum invasive procedure, which reduces trauma to the brain, is cost-effective, and carries a shortened hospital stay with an improved postoperative outcome. Objective: To monitor intracranial pressure changes during intracranial endoscopy among children and adults under general anesthesia/sedation, and to compare the intracranial pressure changes between children and adults receiving general anesthesia and among adults receiving general anesthesia and sedation. Methods: The present cross-sectional study was conducted in one of the tertiary care hospitals of Lucknow. This was carried out in the department of neurosurgery from January 2008 to December 2008. Patients who were not fit for general anesthesia received local anesthesia under sedation. Patients participating in the study were divided into three groups. Intracranial pressure was recorded at specific intervals. Parametric data were subjected to statistical analysis using a student\\s t test. Result: A total of 70 patients were undergoing intracranial endoscopy under general anesthesia during the study period. In both groups A and B, intracranial pressure increases the maximum during inflation of the balloon. In group C, all the variations in ICP were found to be statistically significant. In the comparison of intracranial pressure changes between groups A and B, no significant difference was found. All correlations in the comparison of groups B and C were found to be statistically significant (p< 0.001. Conclusion: There is a need for continuous intraoperative monitoring of ICP intracranial endoscopy, because ICP increases in various stages of the procedure, which can be detrimental to the perfusion of the brain. [Arch Clin Exp Surg 2013; 2(4.000: 240-245

  8. Implantable intraocular pressure monitoring systems: Design considerations

    KAUST Repository

    Arsalan, Muhammad

    2013-12-01

    Design considerations and limitations of implantable Intraocular Pressure Monitoring (IOPM) systems are presented in this paper. Detailed comparison with the state of the art is performed to highlight the benefits and challenges of the proposed design. The system-on-chip, presented here, is battery free and harvests energy from incoming RF signals. This low-cost design, in standard CMOS process, does not require any external components or bond wires to function. This paper provides useful insights to the designers of implantable wireless sensors in terms of design choices and associated tradeoffs. © 2013 IEEE.

  9. NDE and Stress Monitoring on Composite Overwrapped Pressure Vessels Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Damage caused by composite overwrapped pressure vessels (COPVs) failure can be catastrophic. Thus, monitoring condition and stress in the composite overwrap,...

  10. [Reproducibility of arterial pressure measured in the ELSA-Brasil with 24-hour pressure monitoring].

    Science.gov (United States)

    Nascimento, Larissa Rangel; Molina, Maria del Carmen Bisi; Faria, Carolina Perim; Cunha, Roberto de Sá; Mill, José Geraldo

    2013-06-01

    To determine the reproducibility of casual arterial pressure measurement and to confirm pressure diagnosis by monitoring of participants in the ELSA-Brasil (Estudo Longitudinal de Saúde do Adulto - Brazilian Longitudinal Study for Adult Health). Casual blood pressure was measured with an oscilometric device. A sub-sample of participants (N = 255) from Espírito Santo state (Southeastern Brazil) was reevaluated using the same methodology following one to ten weeks and, in addition, underwent arterial blood pressure monitoring. Diagnosis of hypertension used cut off points of 140/90 mmHg for casual pressure and 130/80 mmHg for arterial blood pressure monitoring. White coat hypertension was defined as the presence of hypertension in casual blood pressure and normal arterial blood pressure monitoring, and converse findings characterized masked hypertension. Data are from 230 participants that on the two occasions were free from antihypertensive medication (N1 = 153) or under the same antihypertensive regimen (N2 = 77). Normotension was confirmed by arterial blood pressure monitoring in 120 out of 134 participants of the N1 group. In N2, blood pressure control was confirmed by arterial blood pressure monitoring in 43 of 54 participants with controlled hypertension per casual blood pressure. Overall diagnostic concordance between casual blood pressure and arterial blood pressure monitoring was 78% (kappa = 0.44). In the N1 group, six subjects (4%) presented white coat hypertension, and 23 subjects (25%) presented with masked hypertension. Diagnostic concordance between casual blood pressure and arterial blood pressure monitoring was moderate. The rigorous standardization of casual blood pressure measurement adopted in the ELSA-Brasil study was able to reduce white coat hypertension. The high frequency of masked hypertension may suggest that pressure values obtained by arterial blood pressure monitoring indicate an elevated degree of stress at work.

  11. Design and Evaluation of a Pressure and Temperature Monitoring System for Pressure Ulcer Prevention

    OpenAIRE

    Farve Daneshvar Fard; Sahar Moghimi; Reza Lotfi

    2014-01-01

    Introduction Pressure ulcers are tissue damages resulting from blood flow restriction, which occurs when the tissue is exposed to high pressure for a long period of time. These painful sores are common in patients and elderly, who spend extended periods of time in bed or wheelchair. In this study, a continuous pressure and temperature monitoring system was developed for pressure ulcer prevention. Materials and Methods The monitoring system consists of 64 pressure and 64 temperature sensors on...

  12. CSF concentration gradients of monoamine metabolites in patients with hydrocephalus.

    Science.gov (United States)

    Malm, J; Kristensen, B; Ekstedt, J; Wester, P

    1994-09-01

    Concentration gradients of homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylglycol (MHPG), were assessed in 762 successive CSF fractions (2 ml lumbar CSF) from 15 patients with the adult hydrocephalus syndrome (AHS) and 11 patients with hydrocephalus of other causes (mixed group). A mean volume of 49.6 (SD 11.8) ml CSF was removed in the AHS group and 56.4 (10.2) ml in the mixed group. The CSF was collected with a specially designed carousel fraction collector and the corresponding CSF dynamics were continuously registered by a constant pressure CSF infusion method. Pronounced gradients in CSF HVA and CSF 5-HIAA were seen in both patient groups in the first 25 ml of CSF removed. The concentration curves levelled off, despite the removal of larger amounts of CSF and stabilised at about twice the initial concentrations. This phenomenon has not been described before. Concentrations of HVA and 5-HIAA in the first CSF fraction correlated strongly with concentrations in fractions up to about 40 ml. A positive correlation between the first fraction of CSF HVA and CSF 5-HIAA concentrations and CSF outflow conductance was found in the AHS group. There was no gradient in MHPG. It is suggested that the rostrocaudal gradients in CSF HVA and 5-HIAA may be explained by a downward flow of CSF along the spinal cord with absorption of metabolites occurring during passage. Mixing of CSF from different CSF compartments, extraventricular production sites of CSF, clearance of metabolites to venous blood or extracellular fluid, and CSF outflow conductance are probably important determinants of the plateau phase in patients with hydrocephalus. It is concluded that lumbar CSF does not exclusively reflect the concentrations of HVA, 5-HIAA, or MHPG in the ventricles. It should be noted that these results obtained in patients with hydrocephalus may not be applicable to other groups of patients or normal subjects.

  13. Computational fluid dynamics modelling of cerebrospinal fluid pressure in Chiari malformation and syringomyelia.

    Science.gov (United States)

    Clarke, Elizabeth C; Fletcher, David F; Stoodley, Marcus A; Bilston, Lynne E

    2013-07-26

    The pathogenesis of syringomyelia in association with Chiari malformation (CM) is unclear. Studies of patients with CM have shown alterations in the CSF velocity profile and these could contribute to syrinx development or enlargement. Few studies have considered the fluid mechanics of CM patients with and without syringomyelia separately. Three subject-specific CFD models were developed for a normal participant, a CM patient with syringomyelia and a CM patient without syringomyelia. Model geometries, CSF flow rate data and CSF velocity validation data were collected from MRI scans of the 3 subjects. The predicted peak CSF pressure was compared for the 3 models. An extension of the study performed geometry and flow substitution to investigate the relative effects of anatomy and CSF flow profile on resulting spinal CSF pressure. Based on 50 monitoring locations for each of the models, the CM models had significantly higher magnitude (psyringomyelia mechanisms and relative effects of CSF velocity profile and spinal geometry on CSF pressure.

  14. Biomedical System for Monitoring Pressure Ulcer Development

    OpenAIRE

    Wang, Frank Tinghwa

    2013-01-01

    Pressure ulcers (PU) are one of the leading health concerns among patients living in long-term care facilities and are a common occurrence in hospitals. In the United States alone, over 2.5 million patients will suffer from pressure ulcers each year, and over 60,000 patients will die due to pressure ulcer related complications. The cost to treat pressure ulcers including hospitalization costs is also prohibitively expensive; just in the United States alone it is estimated that $9.2-15.6 Billi...

  15. Clinical evaluation of a new epidural pressure monitor.

    Science.gov (United States)

    Czech, T; Korn, A; Reinprecht, A; Schramm, W; Kimla, T; Spiss, C K

    1993-01-01

    Comparative measuring of epidural pressure using the Spiegelberg probe 1 and ventricular fluid pressure was carried out in 15 neurosurgical intensive-care patients. Deviations in both directions were established, with a trend toward overestimating ventricular pressure in epidural pressure measuring (r = 0.77). Individual pulsations, spontaneous wave courses and therapy-induced pressure changes were reflected without delays. There were no complications observed with probe implantation periods for up to 6 days. The system has been shown to be mechanically stable and easy to implant. We believe the device to be fit for trend monitoring of intracranial pressure. As with other epidural pressure monitoring systems, false assessments of ventricular pressure may lead to wrong decisions as to required therapy.

  16. CSF Obstruction and Malabsorption in Congenital Hydrocephalus

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-11-01

    Full Text Available The relative contribution of CSF malabsorption and obstruction in three different etiological groups of neonatal high-pressure hydrocephalus (HC was assessed in a study at University of Bonn, Germany, and University of Groningen, The Netherlands.

  17. Blood Pressure Home Monitoring in Hypertensive Patients Attending ...

    African Journals Online (AJOL)

    Purpose: To investigate the effect of home monitoring of blood pressure (HMBP) on adherence ... these factors, non compliance to therapy was ... completed by pharmacy students (n = 15) to test ..... training on proper documentation of their BP.

  18. Home monitoring of blood pressure: patients' perception and role of ...

    African Journals Online (AJOL)

    Home monitoring of blood pressure: patients' perception and role of the ... One hundred patients with doctor-diagnosed hypertension were recruited into the study. ... A majority of participants suffer from anxiety (68 %) in response to high blood ...

  19. 21 CFR 884.2700 - Intrauterine pressure monitor and accessories.

    Science.gov (United States)

    2010-04-01

    ... pressure with a catheter placed transcervically into the uterine cavity. The device is used to monitor intensity, duration, and frequency of uterine contractions during labor. This generic type of device...

  20. Wearable Beat to Beat Blood Pressure Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A key component of NASA's human exploration programs is a system that monitors the health of the crew during space missions. The wearable beat-to-beat blood pressure...

  1. Noninvasive automatic blood pressure monitoring does not attenuate nighttime hypotension. Evidence from 24 h intraarterial blood pressure monitoring.

    Science.gov (United States)

    Villani, A; Parati, G; Groppelli, A; Omboni, S; Di Rienzo, M; Mancia, G

    1992-10-01

    Automatic ambulatory blood pressure monitoring makes use of repeated cuff inflations throughout the day and night. This may interfere with the cardiovascular effects of sleep and thus alter the 24 h blood pressure profile. The possibility that intermittent automatic blood pressure measurements prevent nocturnal hypotension was examined in 17 mild or moderate essential hypertensive patients in whom blood pressure was recorded intraarterially for 48 h by the Oxford technique. During the first or the second 24 h period, blood pressure was also monitored noninvasively by the SpaceLabs (Redmond, WA) 5300 (n = 10) and by the Sandoz Pressure System SPS 1558 (Lavanchy Electronique, Prilly, Switzerland) (n = 7) devices, automatic measurements being performed at 15 min intervals during the day and at 30 min intervals during the night. Separate computer analysis of 24 h intraarterial tracings obtained in absence and in concomitance of contralateral automatic blood pressure monitoring showed that the occurrence of automatic measurements had not interfered with the day-night intraarterial blood pressure and heart rate profiles. Thus the frequent cuff inflations that characterize automatic blood pressure monitoring do not attenuate nighttime hypotension and bradycardia. This finding supports use of the noninvasive approach in assessing blood pressure profiles.

  2. abdominal pressure monitoring in varying intra- abdominal ...

    African Journals Online (AJOL)

    TV measurements were achieved using a manual manometer system with a Foley ... relatedness. As the test subjects were organised into related groups, we used intra- .... air before instillation of fluid, contractility of the muscular stomach wall, an exit ... TV techniques both have utility in the clinical setting, with TG pressure.

  3. Role of ambulatory blood pressure monitoring in resistant hypertension.

    Science.gov (United States)

    Grassi, Guido; Bombelli, Michele; Seravalle, Gino; Brambilla, Gianmaria; Dell'oro, Raffaella; Mancia, Giuseppe

    2013-06-01

    Ambulatory blood pressure monitoring has gained growing popularity in the diagnosis and treatment of essential hypertension for several reasons, such as the lack of the so-called white-coat effect, the greater reproducibility as compared with clinic blood pressure, the ability to provide information on blood pressure phenomena of prognostic value and the closer relationship with the risk of cardiovascular morbidity and mortality. All the above-mentioned main features of ambulatory blood pressure monitoring are also true for resistant hypertension. In addition, however, in resistant hypertension, blood pressure monitoring allows one to precisely define the diagnosis of this clinical condition, by excluding the presence of white-coat hypertension, which is responsible for a consistent number of "false" resistant hypertensive cases. The approach also allows one to define the patterns of blood pressure variability in this clinical condition, as well as its relationships with target organ damage. Finally, it allows one to assess the effects of therapeutic interventions, such as renal nerves ablation, aimed at improving blood pressure control in this hypertensive state. The present paper will critically review the main features of ambulatory blood pressure monitoring in resistant hypertension, with particular emphasis on the diagnosis and treatment of this high-risk hypertensive state.

  4. A Sensitive and Biodegradable Pressure Sensor Array for Cardiovascular Monitoring.

    Science.gov (United States)

    Boutry, Clementine M; Nguyen, Amanda; Lawal, Qudus Omotayo; Chortos, Alex; Rondeau-Gagné, Simon; Bao, Zhenan

    2015-11-18

    An array of highly sensitive pressure sensors entirely made of biodegradable materials is presented, designed as a single-use flexible patch for application in cardiovascular monitoring. The high sensitivity in combination with fast response time is unprecedented when compared to recent reports on biodegradable pressure sensors (sensitivity three orders of magnitude higher), as illustrated by pulse wave velocity measurements, toward hypertension detection.

  5. Monitoring temperature and pressure over surfaces using sensitive paints

    Science.gov (United States)

    Guerrero-Viramontes, J. Ascención; Moreno Hernández, David; Mendoza Santoyo, Fernando; Morán Loza, José Miguel; García Arreola, Alicia

    2007-03-01

    Two techniques for monitoring temperature and pressure variations over surfaces using sensitive paints are presented. The analysis is done by the acquisition of a set of images of the surface under analysis. The surface is painted by a paint called Pressure Sensitive Paint (PSP) for pressure measurements and Temperature Sensitive Paints (TSP) for temperature measurements. These kinds of paints are deposited over the surface under analysis. The recent experimental advances in calibration process are presented in this paper.

  6. Wearable Beat-to-Beat Blood Pressure Monitor

    Science.gov (United States)

    Lee, Yong Jin

    2015-01-01

    Linea Research Corporation has developed a wearable noninvasive monitor that provides continuous blood pressure and heart rate measurements in extreme environments. Designed to monitor the physiological effects of astronauts' prolonged exposure to reduced-gravity environments as well as the effectiveness of various countermeasures, the device offers wireless connectivity to allow transfer of both real-time and historical data. It can be modified to monitor the health status of astronaut crew members during extravehicular missions.

  7. Design and Evaluation of a Pressure and Temperature Monitoring System for Pressure Ulcer Prevention

    Directory of Open Access Journals (Sweden)

    Farve Daneshvar Fard

    2014-08-01

    Full Text Available Introduction Pressure ulcers are tissue damages resulting from blood flow restriction, which occurs when the tissue is exposed to high pressure for a long period of time. These painful sores are common in patients and elderly, who spend extended periods of time in bed or wheelchair. In this study, a continuous pressure and temperature monitoring system was developed for pressure ulcer prevention. Materials and Methods The monitoring system consists of 64 pressure and 64 temperature sensors on a 40×50 cm2 sheet. Pressure and temperature data and the corresponding maps were displayed on a computer in real-time. Risk assessment could be performed by monitoring and recording absolute pressure and temperature values, as well as deviations over time. Furthermore, a posture detection procedure was proposed for sitting posture identification. Information about the patient’s movement history may help caregivers make informed decisions about the patient’s repositioning and ulcer prevention strategies. Results Steady temporal behaviour of the designed system and repeatability of the measurements were evaluated using several particular tests. The results illustrated that the system could be utilized for continuous monitoring of interface pressure and temperature for pressure ulcer prevention. Furthermore, the proposed method for detecting sitting posture was verified using a statistical analysis. Conclusion A continuous time pressure and temperature monitoring system was presented in this study. This system may be suited for pressure ulcer prevention given its feasibility for simultaneous monitoring of pressure and temperature and alarming options. Furthermore, a method for detecting different sitting postures was proposed and verified. Pressure ulcers in wheelchair-bound patients may be prevented using this sitting posture detection method.

  8. Oscillometric continuous blood pressure sensing for wearable health monitoring system

    CERN Document Server

    Gelao, Gennaro; Passaro, Vittorio M N; Perri, Anna Gina

    2015-01-01

    In this paper we present an acquisition chain for the measurement of blood arterial pressure based on the oscillometric method. This method does not suffer from any limitation as the well-known auscultatory method and it is suited for wearable health monitoring systems. The device uses a pressure sensor whose signal is filtered, digitalized and analyzed by a microcontroller. Local analysis allows the evaluation of the systolic and diastolic pressure values which can be used for local alarms, data collection and remote monitoring.

  9. Cuff inflation during ambulatory blood pressure monitoring and heart rate

    Directory of Open Access Journals (Sweden)

    Mia Skov-Madsen

    2008-11-01

    Full Text Available Mia Skov-Madsen, My Svensson, Jeppe Hagstrup ChristensenDepartment of Nephrology, Aarhus University Hospital, Aalborg, DenmarkIntroduction: Twenty four-hour ambulatory blood pressure monitoring is a clinically validated procedure in evaluation of blood pressure (BP. We hypothesised that the discomfort during cuff inflation would increase the heart rate (HR measured with 24-h ambulatory BP monitoring compared to a following HR measurement with a 24-h Holter monitor.Methods: The study population (n = 56 were recruited from the outpatient’s clinic at the Department of Nephrology, Aalborg Hospital, Aarhus University Hospital at Aalborg, Denmark. All the patients had chronic kidney disease (CKD. We compared HR measured with a 24-h Holter monitor with a following HR measured by a 24-h ambulatory BP monitoring.Results: We found a highly significant correlation between the HR measured with the Holter monitor and HR measured with 24-h ambulatory blood pressure monitoring (r = 0.77, p < 0.001. Using the Bland-Altman plot, the mean difference in HR was only 0.5 beat/min during 24 hours with acceptable limits of agreement for both high and low HR levels. Dividing the patients into groups according to betablocker treatment, body mass index, age, sex, angiotensin-converting enzyme inhibitor treatment, statins treatment, diuretic treatment, or calcium channel blocker treatment revealed similar results as described above.Conclusion: The results indicate that the discomfort induced by cuff inflation during 24-h ambulatory BP monitoring does not increase HR. Thus, 24-h ambulatory BP monitoring may be a reliable measurement of the BP among people with CKD.Keywords: ambulatory blood pressure monitoring, Holter monitoring, heart rate, chronic kidney disease, hypertension

  10. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...... device for monitoring blood pressure in 35 patients with cirrhosis and 35 healthy matched controls. During the daytime, SBP, DBP, and MAP were significantly lower in the patients than in the controls (median 118 vs. 127; 70 vs. 78; 86 vs. 94 mm Hg, P pressures......, but surprisingly normal arterial blood pressure during the nighttime, and the circadian variation in blood pressure and HR is diminished, probably because of an almost unaltered cardiac output during the 24 hours. These results may reflect a major defect in the ability of optimal regulation of blood pressure...

  11. Noninvasive continuous arterial blood pressure monitoring with Nexfin®.

    Science.gov (United States)

    Martina, Jerson R; Westerhof, Berend E; van Goudoever, Jeroen; de Beaumont, Edouard M F H; Truijen, Jasper; Kim, Yu-Sok; Immink, Rogier V; Jöbsis, Dorothea A; Hollmann, Markus W; Lahpor, Jaap R; de Mol, Bas A J M; van Lieshout, Johannes J

    2012-05-01

    If invasive measurement of arterial blood pressure is not warranted, finger cuff technology can provide continuous and noninvasive monitoring. Finger and radial artery pressures differ; Nexfin® (BMEYE, Amsterdam, The Netherlands) measures finger arterial pressure and uses physiologic reconstruction methodologies to obtain values comparable to invasive pressures. Intra-arterial pressure (IAP) and noninvasive Nexfin arterial pressure (NAP) were measured in cardiothoracic surgery patients, because invasive pressures are available. NAP-IAP differences were analyzed during 30 min. Tracking was quantified by within-subject precision (SD of individual NAP-IAP differences) and correlation coefficients. The ranges of pressure change were quantified by within-subject variability (SD of individual averages of NAP and IAP). Accuracy and precision were expressed as group average ± SD of the differences and considered acceptable when smaller than 5 ± 8 mmHg, the Association for the Advancement of Medical Instrumentation criteria. NAP and IAP were obtained in 50 (34-83 yr, 40 men) patients. For systolic, diastolic, mean arterial, and pulse pressure, median (25-75 percentiles) correlation coefficients were 0.96 (0.91-0.98), 0.93 (0.87-0.96), 0.96 (0.90-0.97), and 0.94 (0.85-0.98), respectively. Within-subject precisions were 4 ± 2, 3 ± 1, 3 ± 2, and 3 ± 2 mmHg, and within-subject variations 13 ± 6, 6 ± 3, 9 ± 4, and 7 ± 4 mmHg, indicating precision over a wide range of pressures. Group average ± SD of the NAP-IAP differences were -1 ± 7, 3 ± 6, 2 ± 6, and -3 ± 4 mmHg, meeting criteria. Differences were not related to mean arterial pressure or heart rate. Arterial blood pressure can be measured noninvasively and continuously using physiologic pressure reconstruction. Changes in pressure can be followed and values are comparable to invasive monitoring.

  12. Noncontact Monitoring of Respiration by Dynamic Air-Pressure Sensor.

    Science.gov (United States)

    Takarada, Tohru; Asada, Tetsunosuke; Sumi, Yoshihisa; Higuchi, Yoshinori

    2015-01-01

    We have previously reported that a dynamic air-pressure sensor system allows respiratory status to be visually monitored for patients in minimally clothed condition. The dynamic air-pressure sensor measures vital information using changes in air pressure. To utilize this device in the field, we must clarify the influence of clothing conditions on measurement. The present study evaluated use of the dynamic air-pressure sensor system as a respiratory monitor that can reliably detect change in breathing patterns irrespective of clothing. Twelve healthy volunteers reclined on a dental chair positioned horizontally with the sensor pad for measuring air-pressure signals corresponding to respiration placed on the seat back of the dental chair in the central lumbar region. Respiratory measurements were taken under 2 conditions: (a) thinly clothed (subject lying directly on the sensor pad); and (b) thickly clothed (subject lying on the sensor pad covered with a pressure-reducing sheet). Air-pressure signals were recorded and time integration values for air pressure during each expiration were calculated. This information was compared with expiratory tidal volume measured simultaneously by a respirometer connected to the subject via face mask. The dynamic air-pressure sensor was able to receive the signal corresponding to respiration regardless of clothing conditions. A strong correlation was identified between expiratory tidal volume and time integration values for air pressure during each expiration for all subjects under both clothing conditions (0.840-0.988 for the thinly clothed condition and 0.867-0.992 for the thickly clothed condition). These results show that the dynamic air-pressure sensor is useful for monitoring respiratory physiology irrespective of clothing.

  13. CSF total protein

    Science.gov (United States)

    CSF total protein is a test to determine the amount of protein in your spinal fluid, also called cerebrospinal fluid (CSF). ... The normal protein range varies from lab to lab, but is typically about 15 to 60 milligrams per deciliter (mg/dL) ...

  14. Continuous monitoring of barometric pressure in deep mines

    Energy Technology Data Exchange (ETDEWEB)

    Trutwin, W.; Mironowicz, W.; Wasilewski, S.; Krawczyk, J. [Research and Development Centre for Electrical Engineering and Automation in Mining EMAG, Katowice (Poland)

    2005-07-01

    Barometric pressure and its variation in deep underground workings have a considerable effect on ventilation conditions. Pressure changes which create transient states of air flow and air parameters in workings are especially significant. Experiments have shown that pressure changes have a remarkable effect on air parameters at mine workings. Continuous monitoring of the barometric pressure on the surface of mines allows for the detection of changes in pressure which influence alternations of pressure in the underground areas of mines. Important factors are the internal disturbances of pressure within a mine ventilation system due to variable conditions of fan operation and the operation of a winding machine where a mine cage moving in a shaft causes piston like disturbances. Local transient disturbances caused by temporary opening/closing of air stoppings due to personnel or underground transport traffic are of importance. The results of over two years of observations of barometric pressure and its influence on pressure variation in underground mine workings are presented. The observations were possible through the installation of pressure sensors at selected points of the downcast shaft in a mine. Of interest are the observations of the transient states of pressure and other air parameters caused by emergency fan stoppage, movement of a mine cage and changes due to the opening of air stoppings. Data acquired during experiments of opening and closing air stoppings were used for the validation of a flow model in a long working. 13 refs., 15 figs.

  15. Intracranial pressure monitoring in severe traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Apetrei Al. Cosmin

    2014-06-01

    Full Text Available Intracranial pressure monitoring seems to be an indispensable stage in management of severe traumatic brain injured patient. Since 2009, this technique completes our trauma protocol. The study has been carried out from 2011 to 2013 in Prof. Dr. N. Oblu hospital in Iasi. There have been included in the study patients with severe craniocerebral trauma, who had traumatic brain lesions CT detected and Glasgow score between 3 and 8. The age ranged from 16 to 60, an average of 35.5 years old. 50% of the studied cases had a favorable outcome. Diagrams associated to this category of patients showed increases in intracranial pressure above normal values but without repeated values above 50 mm Hg. Most of those patients had a good evolution under medical treatment. Monitoring intracranial pressure is an extremely useful stage in treating intracranial high pressure in traumatology and it should be included in the equipment of any intensive therapy section caring traumatic patients

  16. Continuous ventricular cerebrospinal fluid drainage with intracranial pressure monitoring for management of posttraumatic diffuse brain swelling

    Directory of Open Access Journals (Sweden)

    Almir Ferreira de Andrade

    2011-02-01

    Full Text Available BACKGROUND: Ventricular drainage has played an important role in the management of traumatic brain-injured patients. The aim of the present study was describe outcomes in a series of 57 patients with diffuse brain swelling underwent to intracranial pressure (ICP monitoring. METHOD: Fifty-eight patients with diffuse posttraumatic brain swelling, were evaluated prospectively. The Glasgow Coma Scale (GCS scores of patients varied from 4 to 12. Patients groups divided according to GCS and age. Patient neurological assessment was classified as favorable, unfavorable, and death. RESULTS: Mechanisms of injury were vehicle accidents in 72.4% and falls in 15.6%. 54% of patients had GCS scores between 6 and 8. There were no statistical differences, regarding outcome, between groups separated by age. In the adults group (n=47, 44.7% evolved favorably. CONCLUSION: Our results indicate a poor prognosis in patients with brain swelling. We believe that continuous ventricular CSF drainage with ICP monitoring is a simple method as an adjunct in the management of these patients.

  17. Self-monitoring of blood pressure during pregnancy

    DEFF Research Database (Denmark)

    Lihme, Frederikke F; Madsen, Mette E; Lykke, Jacob A

    2017-01-01

    OBJECTIVE: The aim of this study was to assess the feasibility of self-monitoring of blood pressure with a semiautomatic device in pregnant women. PARTICIPANTS AND METHODS: Women attending routine obstetrical ultrasound scanning were invited to participate. The hospital staff initially demonstrated...... arterial blood pressure (MAP) and were compared using the paired sample t-test. Mean values and differences of systolic and diastolic pressure were plotted in Bland-Altman plots to test the agreement of the measurements. Finally, a mean evaluation score was calculated. RESULTS: One hundred pregnant women...

  18. Safety profile and probe placement accuracy of intraspinal pressure monitoring for traumatic spinal cord injury: Injured Spinal Cord Pressure Evaluation study.

    Science.gov (United States)

    Phang, Isaac; Zoumprouli, Argyro; Saadoun, Samira; Papadopoulos, Marios C

    2016-09-01

    OBJECTIVE A novel technique for monitoring intraspinal pressure and spinal cord perfusion pressure in patients with traumatic spinal cord injury was recently described. This is analogous to monitoring intracranial pressure and cerebral perfusion pressure in patients with traumatic brain injury. Because intraspinal pressure monitoring is a new technique, its safety profile and impact on early patient care and long-term outcome after traumatic spinal cord injury are unknown. The object of this study is to review all patients who had intraspinal pressure monitoring to date at the authors' institution in order to define the accuracy of intraspinal pressure probe placement and the safety of the technique. METHODS At the end of surgery to fix spinal fractures, a pressure probe was inserted intradurally to monitor intraspinal pressure at the injury site. Postoperatively, CT scanning was performed within 48 hours and MRI at 2 weeks and 6 months. Neurointensive care management and complications were reviewed. The American Spinal Injury Association Impairment Scale (AIS) grade was determined on admission and at 2 to 4 weeks and 12 to 18 months postoperation. RESULTS To date, 42 patients with severe traumatic spinal cord injuries (AIS Grades A-C) had undergone intraspinal pressure monitoring. Monitoring started within 72 hours of injury and continued for up to a week. Based on postoperative CT and MRI, the probe position was acceptable in all patients, i.e., the probe was located at the site of maximum spinal cord swelling. Complications were probe displacement in 1 of 42 patients (2.4%), CSF leakage that required wound resuturing in 3 of 42 patients (7.1%), and asymptomatic pseudomeningocele that was diagnosed in 8 of 42 patients (19.0%). Pseudomeningocele was diagnosed on MRI and resolved within 6 months in all patients. Based on the MRI and neurological examination results, there were no serious probe-related complications such as meningitis, wound infection, hematoma

  19. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    were almost similar in the two groups (108 vs. 110; 65 vs. 67; 78 vs. 82 mm Hg, NS). Conversely, HR was significantly higher in the patients both in the daytime (86 vs. 72/min, P pressure and HR from daytime......Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...... device for monitoring blood pressure in 35 patients with cirrhosis and 35 healthy matched controls. During the daytime, SBP, DBP, and MAP were significantly lower in the patients than in the controls (median 118 vs. 127; 70 vs. 78; 86 vs. 94 mm Hg, P pressures...

  20. [THE REMOTE MONITORING OF ARTERIAL PRESSURE AND RATE OF HEARTBEATS].

    Science.gov (United States)

    Shalkovskii, A G; Kuptsov, S M; Berseneva, E A

    2015-01-01

    The article considers issues of necessity of development and implementation of remote monitoring of arterial blood pressure and rate of heartbeats as a mean of enhancing quality of medical care of patients. The main characteristics of development of specialized automated system as an integral component of the project is considered too.

  1. Significant practice pattern variations associated with intracranial pressure monitoring.

    Science.gov (United States)

    Olson, DaiWai M; Lewis, Lisa S; Bader, Mary Kay; Bautista, Cynthia; Malloy, Rachel; Riemen, Kristina E; McNett, Molly M

    2013-08-01

    The purpose of this study was to describe nursing practice in the care of patients with intracranial pressure monitoring. Although standards for care of such patients have been established, there continue to be variations in the nursing practice. This was an observational study in which data were collected from 28 nurse-patient dyads at 16 different hospitals across the United States. Each dyad was observed for 2 hours; nursing actions and patient responses including intracranial pressure readings were documented. Differences in the care of patients with intracranial pressure monitoring were prevalent. Variations in practice were prompted by healthcare provider prescriptions as well as nursing decisions. Prescriptions and interventions were often not supported by the available scientific evidence. For more insights from the authors, see Supplemental Digital Content 1, at http://links.lww.com/JNN/A7.

  2. Investigating the efficacy of subharmonic aided pressure estimation for portal vein pressures and portal hypertension monitoring.

    Science.gov (United States)

    Dave, Jaydev K; Halldorsdottir, Valgerdur G; Eisenbrey, John R; Merton, Daniel A; Liu, Ji-Bin; Zhou, Jian-Hua; Wang, Hsin-Kai; Park, Suhyun; Dianis, Scott; Chalek, Carl L; Lin, Feng; Thomenius, Kai E; Brown, Daniel B; Forsberg, Flemming

    2012-10-01

    The efficacy of using subharmonic emissions from Sonazoid microbubbles (GE Healthcare, Oslo, Norway) to track portal vein pressures and pressure changes was investigated in 14 canines using either slow- or high-flow models of portal hypertension (PH). A modified Logiq 9 scanner (GE Healthcare, Milwaukee, WI, USA) operating in subharmonic mode (f(transmit): 2.5 MHz, f(receive): 1.25 MHz) was used to collect radiofrequency data at 10-40% incident acoustic power levels with 2-4 transmit cycles (in triplicate) before and after inducing PH. A pressure catheter (Millar Instruments, Inc., Houston, TX, USA) provided reference portal vein pressures. At optimum insonification, subharmonic signal amplitude changes correlated with portal vein pressure changes; r ranged from -0.82 to -0.94 and from -0.70 to -0.73 for PH models considered separately or together, respectively. The subharmonic signal amplitudes correlated with absolute portal vein pressures (r: -0.71 to -0.79). Statistically significant differences between subharmonic amplitudes, before and after inducing PH, were noted (p ≤ 0.01). Portal vein pressures estimated using subharmonic aided pressure estimation did not reveal significant differences (p > 0.05) with respect to the pressures obtained using the Millar pressure catheter. Subharmonic-aided pressure estimation may be useful clinically for portal vein pressure monitoring.

  3. Comparison of noninvasive blood pressure monitoring with invasive arterial pressure monitoring in medical ICU patients with septic shock.

    Science.gov (United States)

    Riley, Leonard E; Chen, Guoqing John; Latham, Heath E

    2017-08-01

    In the critically ill, the insertion of peripheral arterial catheters to monitor hemodynamics is a low-risk procedure, but carries the potential for complications. This study was designed to compare invasive and noninvasive blood pressure measurements in patients with septic shock in a medical ICU. We carried out a prospective observational study of patients admitted with septic shock and a radially inserted peripheral arterial catheter in the medical ICU with 31 adult patients who underwent four pairs of simultaneous noninvasive and invasive blood pressure measurements (124 comparisons), with the invasive blood pressure taken as the gold standard. Agreements between invasive and noninvasive blood pressure methods were assessed using Bland-Altman analysis, and clinical significance was determined by the European Society of Hypertension criteria. In all patients, noninvasive systolic (P=0.0385), diastolic (Parterial pressures (Ppressure measurements did not correlate clinically according to the European Society of Hypertension criteria. In our patients admitted to the medical ICU with septic shock, noninvasive blood pressure monitoring did not clinically correlate with invasive blood pressure measurements.

  4. Heart-rate monitoring by air pressure and causal analysis

    Science.gov (United States)

    Tsuchiya, Naoki; Nakajima, Hiroshi; Hata, Yutaka

    2011-06-01

    Among lots of vital signals, heart-rate (HR) is an important index for diagnose human's health condition. For instance, HR provides an early stage of cardiac disease, autonomic nerve behavior, and so forth. However, currently, HR is measured only in medical checkups and clinical diagnosis during the rested state by using electrocardiograph (ECG). Thus, some serious cardiac events in daily life could be lost. Therefore, a continuous HR monitoring during 24 hours is desired. Considering the use in daily life, the monitoring should be noninvasive and low intrusive. Thus, in this paper, an HR monitoring in sleep by using air pressure sensors is proposed. The HR monitoring is realized by employing the causal analysis among air pressure and HR. The causality is described by employing fuzzy logic. According to the experiment on 7 males at age 22-25 (23 on average), the correlation coefficient against ECG is 0.73-0.97 (0.85 on average). In addition, the cause-effect structure for HR monitoring is arranged by employing causal decomposition, and the arranged causality is applied to HR monitoring in a setting posture. According to the additional experiment on 6 males, the correlation coefficient is 0.66-0.86 (0.76 on average). Therefore, the proposed method is suggested to have enough accuracy and robustness for some daily use cases.

  5. Ambulatory blood pressure monitoring during pregnancy with a new, small, easily concealed monitor.

    Science.gov (United States)

    Tape, T G; Rayburn, W F; Bremer, K D; Schnoor, T A

    1994-12-01

    Before establishing the utility of ambulatory blood pressure monitoring during pregnancy, we evaluated the accuracy of a small, easily concealed monitor. The 59 normotensive pregnant patients were between 13 and 26 gestational weeks. For each monitor reading, two trained observers independently and simultaneously recorded blood pressures using a mercury manometer connected to the monitor cuff. Seven readings in three positions (sitting upright, semirecumbent, standing) were performed on each patient. Averaged differences between the observers' and monitor readings varied from -2.2 to -0.9 mm Hg (systolic) and from -2.8 to -0.6 (fifth-phase diastolic), indicating slight but clinically unimportant overestimation by the monitor. Correlations between averaged observers' readings and the monitor ranged from 0.79 to 0.92 (systolic) and from 0.85 to 0.92 (fifth-phase diastolic). Overall, the observers agreed with the monitor within 5 mm Hg on 94% of systolic readings and 99% of fifth-phase diastolic readings. There was no statistically significant difference in accuracy with changes in body position. We conclude that this small, quiet, noninvasive device accurately determined blood pressures during pregnancy.

  6. Online Monitoring of Composite Overwrapped Pressure Vessels (COPV)

    DEFF Research Database (Denmark)

    Pereira, Gilmar Ferreira; Figueiredo, Joana; Faria, Hugo

    2015-01-01

    Composite overwrapped pressure vessels (COPV) have been increasingly pointed to as the most effective solution for high pressure storage of liquid and gaseous fluids. Reasonably high stiffness-to-weight ratios make them suitable for both static and mobile applications. However, higher operating...... pressures are sought continuously, to get higher energy densities in such storage systems, and safety aspects become critical. Thus, reliable design and test procedures are required to reduce the risks of undesired and unpredicted failures. An in-service health monitoring system may contribute to a better...... product development, design and optimization, as well as to minimize the risks and improve the public acceptance. Within the scope of developing different COPV models for a wide range of operating pressures and applications, optical fiber Bragg grating (FBG) sensors were embedded in the liner...

  7. [Intraoperative monitoring of oxygen tissue pressure: Applications in vascular neurosurgery].

    Science.gov (United States)

    Arikan, Fuat; Vilalta, Jordi; Torne, Ramon; Chocron, Ivette; Rodriguez-Tesouro, Ana; Sahuquillo, Juan

    2014-01-01

    Ischemic lesions related to surgical procedures are a major cause of postoperative morbidity in patients with cerebral vascular disease. There are different systems of neuromonitoring to detect intraoperative ischemic events, including intraoperative monitoring of oxygen tissue pressure (PtiO2). The aim of this article was to describe, through the discussion of 4 cases, the usefulness of intraoperative PtiO2 monitoring during vascular neurosurgery. In presenting these cases, we demonstrate that monitoring PtiO2 is a reliable way to detect early ischemic events during surgical procedures. Continuous monitoring of PtiO2 in an area at risk allows the surgeon to resolve the cause of the ischemic event before it evolves to an established cerebral infarction. Copyright © 2014 Sociedad Española de Neurocirugía. Published by Elsevier España. All rights reserved.

  8. Detection of Soluble Amyloid-β Oligomers and Insoluble High-Molecular-Weight Particles in CSF: Development of Methods with Potential for Diagnosis and Therapy Monitoring of Alzheimer's Disease

    Directory of Open Access Journals (Sweden)

    Susanne Aileen Funke

    2011-01-01

    Full Text Available The diagnosis of probable Alzheimer's disease (AD can be established premortem based on clinical criteria like neuropsychological tests. Post mortem, specific neuropathological changes like amyloid plaques define AD. However, the standard criteria based on medical history and mental status examinations do not take into account the long preclinical features of the disease, and a biomarker for improved diagnosis of AD is urgently needed. In a large number of studies, amyloid-β (Aβ monomer concentrations in CSF of AD patients are consistently and significantly reduced when compared to healthy controls. Therefore, monomeric Aβ in CSF was suggested to be a helpful biomarker for the diagnosis of preclinical AD. However, not the monomeric form, but Aβ oligomers have been shown to be the toxic species in AD pathology, and their quantification and characterization could facilitate AD diagnosis and therapy monitoring. Here, we review the current status of assay development to reliably and routinely detect Aβ oligomers and high-molecular-weight particles in CSF.

  9. Plateau Waves of Intracranial Pressure and Multimodal Brain Monitoring.

    Science.gov (United States)

    Dias, Celeste; Maia, Isabel; Cerejo, Antonio; Smielewski, Peter; Paiva, José-Artur; Czosnyka, Marek

    2016-01-01

    The aim of this study was to describe multimodal brain monitoring characteristics during plateau waves of intracranial pressure (ICP) in patients with head injury, using ICM+ software for continuous recording. Plateau waves consist of an abrupt elevation of ICP above 40 mmHg for 5-20 min. This is a prospective observational study of patients with head injury who were admitted to a neurocritical care unit and who developed plateau waves. We analyzed 59 plateau waves that occurred in 8 of 18 patients (44 %). At the top of plateau waves arterial blood pressure remained almost constant, but cerebral perfusion pressure, cerebral blood flow, brain tissue oxygenation, and cerebral oximetry decreased. After plateau waves, patients with a previously better autoregulation status developed hyperemia, demonstrated by an increase in cerebral blood flow and brain oxygenation. Pressure and oxygen cerebrovascular reactivity indexes (pressure reactivity index and ORxshort) increased significantly during the plateau wave as a sign of disruption of autoregulation. Bedside multimodal brain monitoring is important to characterize increases in ICP and give differential diagnoses of plateau waves, as management of this phenomenon differs from that of regular ICP.

  10. Pressure mapping with textile sensors for compression therapy monitoring.

    Science.gov (United States)

    Baldoli, Ilaria; Mazzocchi, Tommaso; Paoletti, Clara; Ricotti, Leonardo; Salvo, Pietro; Dini, Valentina; Laschi, Cecilia; Francesco, Fabio Di; Menciassi, Arianna

    2016-08-01

    Compression therapy is the cornerstone of treatment in the case of venous leg ulcers. The therapy outcome is strictly dependent on the pressure distribution produced by bandages along the lower limb length. To date, pressure monitoring has been carried out using sensors that present considerable drawbacks, such as single point instead of distributed sensing, no shape conformability, bulkiness and constraints on patient's movements. In this work, matrix textile sensing technologies were explored in terms of their ability to measure the sub-bandage pressure with a suitable temporal and spatial resolution. A multilayered textile matrix based on a piezoresistive sensing principle was developed, calibrated and tested with human subjects, with the aim of assessing real-time distributed pressure sensing at the skin/bandage interface. Experimental tests were carried out on three healthy volunteers, using two different bandage types, from among those most commonly used. Such tests allowed the trends of pressure distribution to be evaluated over time, both at rest and during daily life activities. Results revealed that the proposed device enables the dynamic assessment of compression mapping, with a suitable spatial and temporal resolution (20 mm and 10 Hz, respectively). In addition, the sensor is flexible and conformable, thus well accepted by the patient. Overall, this study demonstrates the adequacy of the proposed piezoresistive textile sensor for the real-time monitoring of bandage-based therapeutic treatments.

  11. Finger and Palm Dynamic Pressure Monitoring for Basketball Shooting

    Directory of Open Access Journals (Sweden)

    Chiao-Fang Hung

    2017-01-01

    Full Text Available This study verified general inferences on the finger and palm pressure distribution of a basketball player in the moment before that player shoots a basketball through a scientific qualitative testing method. We mounted the sensor on the hands of college basketball players and monitored the dynamic pressure of each player’s hand while the player threw a basketball. The dynamic pressure distribution of the fingers and palm of a basketball player throwing a ball can be verified. According to the experimental results, college basketball players typically use the index finger to control the direction and power of force in the moment before shooting a basketball. This study successfully used a scientific qualitative test method to monitor the dynamic pressure of the fingers and palms of basketball players and verified the general inference that a typical basketball player mainly uses the index finger to control the direction and power of force in the moment before throwing a ball. In the future, this study, measuring the dynamic pressure distribution of the fingers and palm, can be applied to simulate hand manipulation in many biomedical and robotic applications.

  12. Wide vacuum pressure range monitoring by Pirani SAW sensor.

    Science.gov (United States)

    Nicolay, Pascal; Elmazria, Omar; Sarry, Frederic; Bouvot, Laurent; Kambara, Hisanori; Singh, Kanwar J; Alnot, Patrick

    2010-03-01

    A new kind of surface acoustic wave (SAW) sensor has been developed to measure sub-atmospheric pressure below 100 mtorr with accuracy better than 0.1 mtorr. It provides an efficient measuring solution in the pressure range inaccessible in past by conventional diaphragm-based SAW sensors. Indeed, because of the small bending force in lower pressure and limited sensitivity, diaphragm-based SAW sensors are only suited to monitor relatively high pressure with a precision hardly better than 0.5 torr. To reach precision level better than 1 mtorr at sub-atmospheric pressure for vacuum technology applications, a radically different SAW-based solution is necessary. Our device aims to measure sub-atmospheric pressure less than 100 mtorr with a threshold resolution better than 0.1 mtorr. The concept is similar to the one used by Pirani pressure gauges. However, it is claimed that a heated and suspended SAW device should have better sensitivity. A theoretical model based on the basic concepts of gas kinetic theory and thermodynamics is presented. The validity of the model is checked by comparison between theoretical and experimental results.

  13. Zero drift of intraventricular and subdural intracranial pressure monitoring systems

    OpenAIRE

    2013-01-01

    【Abstract】Objective: To assess zero drift of intra-ventricular and subdural intracranial pressure (ICP) moni-toring systems. Methods: A prospective study was conducted in pa-tients who received Codman ICP monitoring in the neuro-surgical department from January 2010 to December 2011. According to the location of sensors, the patients were ca-tegorized into two groups: intraventricular group and sub-dural group. Zero drift between the two groups and its as-sociation with the duratio...

  14. Observation of the CSF pulsatile flow in the aqueduct using cine MRI with presaturation bolus tracking, 3; The pathophysiological significance of the pulsatile flow patterns in adult patients with ventriculomegaly

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Satoshi (Tokyo Medical Coll. (Japan))

    1992-06-01

    The to-and-fro motion patterns of the CSF flow in the aqueduct in ten normal adults, ten patients with secondary normal-pressure hydrocephalus (NPH), and fourteen patients with idiopathic ventriculomegaly were analyzed using cine MRI with presaturation bolus tracking. The to-and-fro motion patterns of the CSF flow in the aqueduct were thus classified into four types according to their maximum velocity and the relative time duration of their flow in the rostral and caudal directions. The correlation between the clinical symptoms, the CT findings, the RI-cisternography findings, the results of the ICP monitorings, and the CSF pulsatile-flow patterns were then analyzed. In secondary NPH disclosing frequent B waves on ICP monitoring, the maximum velocity of the CSF flow in the aqueduct was over 15 mm/sec, and the duration of the CSF flow was longer in the caudal direction than in the rostral direction. Furthermore, the faster the maximum velocity of the CSF flow, the larger the ventricular size on CT and the more severe the CSF malabsorption on cisternography. In idiopathic ventriculomegaly, only two cases demonstrated the same CSF flow pattern as was shown in secondary NPH; the other cases demonstrated other CSF flow patterns, which were considered to indicate hydrocephalus ex vacuo or arrested hydrocephalus. The CSF pulsatile-flow pattern was assumed to change according to the degree of the CSF circulatory disorder, its compensatory process, and the plasticity of the brain. The investigation of the CSF pulsatile flow gives important information for the evaluation of various hydrocephalic conditions. (author).

  15. Intracranial pressure monitoring and outcomes after traumatic brain injury

    Science.gov (United States)

    Lane, Peter L.; Skoretz, Terry G.; Doig, Gordon; Girotti, Murray J.

    2000-01-01

    Objective Uncontrolled intracranial hypertension after traumatic brain injury (TBI) contributes significantly to the death rate and to poor functional outcome. There is no evidence that intracranial pressure (ICP) monitoring alters the outcome of TBI. The objective of this study was to test the hypothesis that insertion of ICP monitors in patients who have TBI is not associated with a decrease in the death rate. Design Study of case records. Methods The data files from the Ontario Trauma Registry from 1989 to 1995 were examined. Included were all cases with an Injury Severity Score (ISS) greater than 12 from the 14 trauma centres in Ontario. Cases identifying a Maximum Abbreviated Injury Scale score in the head region (MAIS head) greater than 3 were selected for further analysis. Logistic regression analyses were conducted to investigate the relationship between ICP and death. Results Of 9001 registered cases of TBI, an MAIS head greater than 3 was recorded in 5507. Of these patients, 541 (66.8% male, mean age 34.1 years) had an ICP monitor inserted. Their average ISS was 33.4 and 71.7% survived. There was wide variation among the institutions in the rate of insertion of ICP monitors in these patients (ranging from 0.4% to over 20%). Univariate logistic regression indicated that increased MAIS head, ISS, penetrating trauma and the insertion of an ICP monitor were each associated with an increased death rate. However, multivariate analyses controlling for MAIS head, ISS and injury mechanism indicated that ICP monitoring was associated with significantly improved survival (p < 0.015). Conclusions ICP monitor insertion rates vary widely in Ontario’s trauma hospitals. The insertion of an ICP monitor is associated with a statistically significant decrease in death rate among patients with severe TBI. This finding strongly supports the need for a prospective randomized trial of management protocols, including ICP monitoring, in patients with severe TBI. PMID:11129833

  16. [Outpatient blood pressure monitoring is not always necessary].

    Science.gov (United States)

    Divisón Garrote, J A

    It is clear that clinical measurements of blood pressure can lead to errors in the diagnostic process and follow-up of patients with hypertension. Scientific societies recommend other measurement methods, such as home measurements and outpatient monitoring. Outpatient monitoring might be the golden standard but, nowadays has an important limitation-its availability. Home measurements solve 80-90% of the doubts of the diagnostic process and follow-up of patients with hypertension, and its higher availability and acceptance by the patient are clear. Home measurements should be used in the diagnostic process of arterial hypertension as a screening test for white coat hypertension and masked hypertension. They should be used as a screening test for resistant hypertension in the follow-up of patients with high blood pressure. Besides, in the follow-up of patients with hypertension home measurements have shown that they can contribute to treatment adherence, reduce clinical inertia and make data teletransmission possible, aspects that have proven to help improve the degree of control of hypertensive patients. Therefore, home measurements would be the treatment of choice for the diagnosis and follow-up of most patients with hypertension. We should consider home measurements and outpatient monitoring as complementary methods for the diagnosis and follow-up of patients with high blood pressure. Copyright © 2016. Publicado por Elsevier España, S.L.U.

  17. APPLICATION OF THE ROOF DISTURBANCETO MONITORING AND PREDICTINGTHE GROUND PRESSURE

    Institute of Scientific and Technical Information of China (English)

    付国彬; 钱鸣高

    1992-01-01

    Based on study of the influence of main roof fracture on ground pressure,this paper considered the immediate roof as a semi-infinite long beam on a Winkler elastic foundation. In the model the coal seam is the foundation and the pressure caused by rnian roof deflection is the load.Having solved the model and analyzed relevant factors,the authors indicate that the disturbance caused by the breakage of the mian roof can be observed in both gates of iongwaii face and explain why it can be. The paper points out that the applicability of the method to obtain the disturbance information by measuring the loads on supports is wider than that by measuring the roof convergence rate. The results are useful for monitoring and predicting ground pressure.

  18. Review on pressure sensors for structural health monitoring

    Science.gov (United States)

    Sikarwar, Samiksha; Satyendra; Singh, Shakti; Yadav, B. C.

    2017-08-01

    This paper reports the state of art in a variety of pressure and the detailed study of various matrix based pressure sensors. The performances of the bridges, buildings, etc. are threatened by earthquakes, material degradations, and other environmental effects. Structural health monitoring (SHM) is crucial to protect the people and also for assets planning. This study is a contribution in developing the knowledge about self-sensing smart materials and structures for the construction industry. It deals with the study of self-sensing as well as mechanical and electrical properties of different matrices based on pressure sensors. The relationships among the compression, tensile strain, and crack length with electrical resistance change are also reviewed.

  19. On preventive blood pressure self-monitoring at home

    DEFF Research Database (Denmark)

    Verdezoto, Nervo; Grönvall, Erik

    2015-01-01

    -called Quantified Self). In this article, we explore socio-technical complexities that may occur when introducing preventive health-measurement technologies into older adults’ daily routines and everyday lives. In particular, the original study investigated blood pressure (BP) measurement in non-clinical settings......, to understand existing challenges, and uncover opportunities for self-monitoring technologies to support preventive healthcare activities among older adults. From our study, several important aspects emerged to consider when designing preventive self-monitoring technology, such as the complexity of guidelines...... to develop better tools to support people’s preventive self-monitoring needs, compared to existing solutions. Supporting the active and informed individual can help improve people’s self-care, awareness, and implementation of preventive care. Based on our study, we also reflect on the findings to illustrate...

  20. Pediatric ambulatory blood pressure monitoring: indications and interpretations.

    Science.gov (United States)

    Flynn, Joseph T; Urbina, Elaine M

    2012-06-01

    The prevalence of hypertension in children and adolescents is increasing, especially in obese and ethnic children. The adverse long-term effects of hypertension beginning in youth are known; therefore, it is important to identify young patients who need intervention. Unfortunately, measuring blood pressure (BP) is difficult due to the variety of techniques available and innate biologic variation in BP levels. Ambulatory BP monitoring may overcome some of the challenges clinicians face when attempting to categorize a young patient's BP levels. In this article, the authors review the use of ambulatory BP monitoring in pediatrics, discuss interpretation of ambulatory BP monitoring, and discuss gaps in knowledge in usage of this technique in the management of pediatric hypertension.

  1. Using Advanced Tensiometers to Monitor Temporal Variations in Pore Pressure

    Science.gov (United States)

    Nichols, R. L.; Young, M. H.; Dixon, K. L.; Rossabi, J.; Hyde, W. K.; Holmes-Burns, H.

    2002-12-01

    The Savannah River Site has installed a comprehensive vadose zone monitoring system (VZMS) at it's low level radioactive waste disposal facility to collect the necessary information to calculate contaminant flux. The VZMS includes water content reflectometers, suction lysimeters, advanced tensiometers (ATs), water flux meters, access ports for neutron probes, and a tipping bucket rain gauge. Forty one ATs were installed from 1999 to 2001 at depths ranging from 2 to 60 feet and have been operated continuously. The installation depths were based on a hydrostatigraphic model developed from core logs, cone penetrometer logs, moisture content profiles, water retention curves model that were obtained during the phased installation of the VZMS. An AT consists of a porous cup installed at a prescribed depth with casing back to the surface and a pressure transducer that is lowered into the casing and connects with the porous cup. The pressure transducer transmits it's signal to a datalogger where the data is stored for future retrieval using a cellular phone communications package. Results from the 2 year operating period show that the AT calibrations are stable and t ATs are capable of extended monitoring of pore pressures in the 0 to 300 cm H2 O range. The ATs had sufficient resolution to detect the naturally occurring fluctuations in pore pressure (1 to 100 cm H2 O over 1 to 72 hours) that resulted from infiltration events at the site. The stable performance of the ATs combined with their ability to detect naturally occurring fluctuations in pore pressure make the ATs a useful tool in measuring temporal pore pressure variations for use in calibrating numerical models of fluid flow in variably saturated porous media.

  2. Zero drift of intraventricular and subdural intracranial pressure monitoring systems

    Institute of Scientific and Technical Information of China (English)

    CHEN Li; DU Hang-gen; YIN Li-chun; HE Min; ZHANG Guo-jun; TIAN Yong; WANG Cheng

    2013-01-01

    Objective:To assess zero drift of intraventricular and subdural intracranial pressure (ICP) monitoring systems.Methods:A prospective study was conducted in patients who received Codman ICP monitoring in the neurosurgical department from January 2010 to December 2011.According to the location of sensors,the patients were categorized into two groups:intraventricular group and subdural group.Zero drift between the two groups and its association with the duration of ICP monitor were analyzed.Results:Totally,22 patients undergoing intraventricular ICP monitoring and 27 receiving subdural ICP monitoring were enrolled.There was no significant difference in duration of ICP monitoring,zero drift value and its absolute value between intraventricular and subdural groups (5.38 d±2.58 d vs 4.58 d±2.24d,0.77 mmHg±2.18 mm Hg vs 1.03 mmHg±2.06mmHg,1.68 mmHg±155 mmHg vs 1.70mmHg±153 mmHg,respectively; all P>0.05).Absolute value of zero drift in both groups significantly rose with the increased duration of ICP monitoring (P<0.05) while zero drift value did not.Moreover,daily absolute value in the intraventricular group was significantly smaller than that in the subdural group (0.27 mm Hg±0.32 mm Hg vs 0.29 mm Hg±0.18 mm Hg,P<0.05).Conclusion:This study demonstrates that absolute value of zero drift significantly correlates with duration of both intraventricular and subdural ICP monitoring.Due to the smaller daily absolute value,ICP values recorded from intraventricular system may be more reliable than those from subdural system.

  3. Using ambulatory blood pressure monitoring to assess blood pressure of firefighters with parental history of hypertension.

    Science.gov (United States)

    de Mattos, Carlos Eduardo; de Mattos, Marco Antonio; Toledo, Daniele Gusmão; de Siqueira Filho, Aristarco Gonçalves

    2006-12-01

    To evaluate the influence of family history of systemic arterial hypertension (FSAH) on the effect of stress from work in Uniformed Firefighters (BMCs) through Ambulatory Blood Pressure Monitoring (ABPM). A prospective case-control study. Sixty-six healthy BMC underwent ABPM during 12 hours of work at the Communication Center (CC). Thirty-four had hypertensive parents (group 1) and thirty-two had normotensive parents (group 2). Group I differed from group 2 in that it showed higher mean systolic (134.1 +/- 9.9 mmHg X 120.8 +/- 9.9 mmHg p pressure, in addition to greater systolic (31.4 +/- 25.6 % X 9.4 +/- 9.4 % p = 0.0001) and diastolic (28.3 +/- 26.6 % X 6.1 +/- 8.9 % p = 0.0001) loads. The prevalence of systemic arterial hypertension (SAH) in group 1 at the workplace was 32.3%. Monitored away from the job, these subjects showed normal blood pressure (functionally hypertensive). Group 2 revealed normal blood pressure (BP) at work. Higher blood pressure in BMC with hypertensive parents is explained independently by the SAH. Subjects who developed SAH during their work at the CC may be considered functionally hypertensive, whereas those with normotensive parents and who underwent psychological stress are free of blood pressure changes.

  4. Blood pressure monitor with a position sensor for wrist placement to eliminate hydrostatic pressure effect on blood pressure measurement.

    Science.gov (United States)

    Sato, Hironori; Koshimizu, Hiroshi; Yamashita, Shingo; Ogura, Toshihiko

    2013-01-01

    Accurate measurement of blood pressure at wrist requires the heart and wrist to be kept at the same level to avoid the effects of hydrostatic pressure. Although a blood pressure monitor with a position sensor that guides appropriate forearm angle without use of a chair and desk has already been proposed, a similar functioning device for measuring upper arm blood pressure with a chair and desk is needed. In this study, a calculation model was first used to explore design of such a system. The findings were then implemented into design of a new blood pressure monitor. Results of various methods were compared. The calculation model of the wrist level from arthrosis angles and interarticulars lengths was developed and considered using published anthropometric dimensions. It is compared with 33 volunteer persons' experimental results. The calculated difference of level was -4.1 to 7.9 (cm) with a fixed chair and desk. The experimental result was -3.0 to 5.5 (cm) at left wrist and -2.1 to 6.3(cm) at right wrist. The absolute difference level equals ±4.8 (mmHg) of blood pressure readings according to the calculated result. This meets the AAMI requirements for a blood pressure monitor. In the conclusion, the calculation model is able to effectively evaluate the difference between the heart and wrist level. Improving the method for maintaining wrist to heart level will improve wrist blood pressure measurement accuracy when also sitting in the chair at a desk. The leading angle of user's forearm using a position sensor is shown to work for this purpose.

  5. Personalizing Intraocular Pressure: Target Intraocular Pressure in the Setting of 24-Hour Intraocular Pressure Monitoring.

    Science.gov (United States)

    Sit, Arthur J; Pruet, Christopher M

    2016-01-01

    Determining target intraocular pressure (IOP) in glaucoma patients is multifaceted, requiring attention to many different factors such as glaucoma type, severity of disease, age, race, family history, corneal thickness and hysteresis, and initial IOP. Even with all these variables accounted for, there are still patients who have progression of the disease despite achieving target IOP. Intraocular pressure variability has been identified as a potential independent risk factor for glaucoma progression but is currently difficult to quantify in individual patients. New technologies enabling measurement of both diurnal and nocturnal IOP may necessitate modifying our concept of target pressure.

  6. Automatic algorithm for monitoring systolic pressure variation and difference in pulse pressure.

    Science.gov (United States)

    Pestel, Gunther; Fukui, Kimiko; Hartwich, Volker; Schumacher, Peter M; Vogt, Andreas; Hiltebrand, Luzius B; Kurz, Andrea; Fujita, Yoshihisa; Inderbitzin, Daniel; Leibundgut, Daniel

    2009-06-01

    Difference in pulse pressure (dPP) reliably predicts fluid responsiveness in patients. We have developed a respiratory variation (RV) monitoring device (RV monitor), which continuously records both airway pressure and arterial blood pressure (ABP). We compared the RV monitor measurements with manual dPP measurements. ABP and airway pressure (PAW) from 24 patients were recorded. Data were fed to the RV monitor to calculate dPP and systolic pressure variation in two different ways: (a) considering both ABP and PAW (RV algorithm) and (b) ABP only (RV(slim) algorithm). Additionally, ABP and PAW were recorded intraoperatively in 10-min intervals for later calculation of dPP by manual assessment. Interobserver variability was determined. Manual dPP assessments were used for comparison with automated measurements. To estimate the importance of the PAW signal, RV(slim) measurements were compared with RV measurements. For the 24 patients, 174 measurements (6-10 per patient) were recorded. Six observers assessed dPP manually in the first 8 patients (10-min interval, 53 measurements); no interobserver variability occurred using a computer-assisted method. Bland-Altman analysis showed acceptable bias and limits of agreement of the 2 automated methods compared with the manual method (RV: -0.33% +/- 8.72% and RV(slim): -1.74% +/- 7.97%). The difference between RV measurements and RV(slim) measurements is small (bias -1.05%, limits of agreement 5.67%). Measurements of the automated device are comparable with measurements obtained by human observers, who use a computer-assisted method. The importance of the PAW signal is questionable.

  7. Intracranial pressure and cerebral perfusion pressure monitoring in non-TBI patients: special considerations.

    Science.gov (United States)

    Helbok, Raimund; Olson, DaiWai M; Le Roux, Peter D; Vespa, Paul

    2014-12-01

    The effect of intracranial pressure (ICP) and the role of ICP monitoring are best studied in traumatic brain injury (TBI). However, a variety of acute neurologic illnesses e.g., subarachnoid hemorrhage, intracerebral hemorrhage, ischemic stroke, meningitis/encephalitis, and select metabolic disorders, e.g., liver failure and malignant, brain tumors can affect ICP. The purpose of this paper is to review the literature about ICP monitoring in conditions other than TBI and to provide recommendations how the technique may be used in patient management. A PubMed search between 1980 and September 2013 identified 989 articles; 225 of which were reviewed in detail. The technique used to monitor ICP in non-TBI conditions is similar to that used in TBI; however, indications for ICP monitoring often are intertwined with the presence of obstructive hydrocephalus and hence the use of ventricular catheters is more frequent. Increased ICP can adversely affect outcome, particularly when it fails to respond to treatment. However, patients with elevated ICP can still have favorable outcomes. Although the influence of ICP-based care on outcome in non-TBI conditions appears less robust than in TBI, monitoring ICP and cerebral perfusion pressure can play a role in guiding therapy in select patients.

  8. Magnetic sensor for arterial distension and blood pressure monitoring.

    Science.gov (United States)

    Ruhhammer, Johannes; Herbstritt, Tamara; Ruh, Dominic; Foerster, Katharina; Heilmann, Claudia; Beyersdorf, Friedhelm; Goldschmidtboeing, Frank; Seifert, Andreas; Woias, Peter

    2014-12-01

    A novel sensor for measuring arterial distension, pulse and pressure waveform is developed and evaluated. The system consists of a magnetic sensor which is applied and fixed to arterial vessels without any blood vessel constriction, hence avoiding stenosis. The measurement principle could be validated by in vitro experiments on silicone tubes, and by in vivo experiments in an animal model, thereby indicating the non-linear viscoelastic characteristics of real blood vessels. The sensor is capable to provide absolute measurements of the dynamically varying arterial diameter. By calibrating the sensor, a long-term monitoring system for continuously measuring blood pressure and other cardiovascular parameters could be developed based on the method described. This will improve diagnostics for high risk patients and enable a better, specific treatment.

  9. Ambulatory Blood Pressure Monitoring – Clinical Practice Recommendations

    Directory of Open Access Journals (Sweden)

    Katalin Mako

    2016-09-01

    Full Text Available Ambulatory blood pressure monitoring (ABPM became a subject of considerable scientific interest. Due to the increasing use of the ABPM in everyday clinical practice it is important that all the users have a correct knowledge on the clinical indications, the methodology of using the device including some technical issues and the interpretation of results. In the last years several guidelines and position papers have been published with recommendations for the monitoring process, reference values, for clinical practice and research. This paper represents a summary of the most important aspects related to the use of ABPM in daily practice, being a synthesis of recommendations from the recent published guidelines and position papers. This reference article presents the practical and technical issues of ABPM, the use of this method in special situations, the clinical interpretation of measured values including the presentation of different ABPM patterns, derived parameters, the prognostic significance and the limitations of this method.

  10. Intracranial pressure monitoring for special patterns of frontal lobe contusions

    Institute of Scientific and Technical Information of China (English)

    DONG Ji-rong; CAI Xue-jian; WANG Biao; WANG Yu-hai; SHI Zhong-hua; LIU Bing; CAI Sang; XU Qin-yi

    2010-01-01

    Objective:To study the effect and indications of intracranial pressure(ICP)monitoring for frontal lobe contusion patients.Methods:During January 2005-December 2008,34 cases of frontal lobe contusion received ICP monitoring in our department(monitoring group).Different treatment protocols were adopted according to the results of ICP.Meanwhile 46 cases of same type of head-injured patients who did not undergo ICP monitoring served as control group.Results:We found that ICP elevated dramatically within 24 hours after head injury if the contusions were located in frontal longitudinal dehiscence,bilateral undersurface of frontal lobe or dispersed in bilateral lobe.After half a year follow-up and on the basis of Glasgow Coma Scale assessment,the monitoring group showed better outcome than the control group with good recovery in 24 cases(70.6%),moderate disability in 7 cases(20.6%),severe disability in 2(5.88%)and death in 1(2.94%).The outcome of control group displayed good condition in 25 cases(54.3%),moderate disabilities in 8(17.4%),severe disability in 7(15.2%),and death in 6(13.0%).Conclusions:Frontal lobe contusions are vulnerable and complex head injuries,especially when the contusions are located in frontal longitudinal dehiscence,bilateral undersurface of frontal lobe or diffused in bilateral lobes.These patients should undergo ICP monitoring regardless of their consciousness status.If ICP elevates over 25 mm Hg,the craniotomy is mandatory and will markedly reduce the mortality and disability of these patients.

  11. [Possibilities of data acquisition, recording and processing based on the system for continuous intracranial pressure and cerebral perfusion pressure monitoring designed at the Department of Neurosurgery of the Jagiellonian University in Cracow].

    Science.gov (United States)

    Czepko, Ryszard; Cieślicki, Krzysztof; Niedźwiedzki, Jerzy; Libionka, Witold; Pietraszko, Wojciech

    2005-01-01

    To describe computer system for intracranial pressure (ICP) monitoring and for infusion testing (IT), and to present current possibilities of analysis of cerebrospinal fluid (CSF) pressure signal. Computer system for pressure signal measurement and acquisition consists of three sensors: for ICP, infusion pressure during IT, and blood pressure measurements. Electric signal from the sensors is transmitted to Temed RMN-201M cardiomonitor, and next after enhancement is subjected to Data Shuttle DS-12-8-5B-AO analog to digital converter. Digital output signal is recorded and analysed'on standard personal computer. Original Windows-compatible software was developed to control the system. The program consists of three blocs: configuration, measurement and readout, and enables selection of voltage range for each of the signal channels, measurement resolution, sampling frequency, calibration and zeroing of the sensors, visualisation of pressure signals on graph, data storage in text format and automatic analysis of IT. Main characteristics of the system include: high sampling frequency (up to 500 Hz), simultaneous data recording from all signal channels, and access to terminal cistern with one puncture needle on IT. Laboratory and clinical tests confirmed high precision of the developed system. ICP CURVE ANALYSIS: The developed software allows for evaluation of the main parameters, of CSF dynamics, prediction of IT course before a steady state is reached as well as spectral analysis of pressure signal. Computer measurement system developed at our department is clinically useful and allows for high precision signal acquisition necessary for advanced scientific analyses of hydrocephalus and intracranial pressure.

  12. Evolution from electrophysiologic to hemodynamic monitoring: the story of left atrial and pulmonary artery pressure monitors

    Directory of Open Access Journals (Sweden)

    Deirdre M Mooney

    2015-10-01

    Full Text Available Heart failure (HF is a costly, challenging and highly prevalent medical condition. Hospitalization for acute decompensation is associated with high morbidity and mortality. Despite application of evidence-based medical therapies and technologies, HF remains a formidable challenge for virtually all healthcare systems. Repeat hospitalizations for acute decompensated HF (ADHF can have major financial impact on institutions and resources. Early and accurate identification of impending ADHF is of paramount importance yet there is limited high quality evidence or infrastructure to guide management in the outpatient setting. Historically, ADHF was identified by physical exam findings or invasive hemodynamic monitoring during a hospital admission; however, advances in medical microelectronics and the advent of device-based diagnostics have enabled long-term ambulatory monitoring of HF patients in the outpatient setting. These monitors have evolved from piggybacking on cardiac implantable electrophysiologic devices to standalone implantable hemodynamic monitors that transduce left atrial or pulmonary artery pressures as surrogate measures of left ventricular filling pressure. As technology evolves, devices will likely continue to miniaturize while their capabilities grow. An important, persistent challenge that remains is developing systems to translate the large volumes of real-time data, particularly data trends, into actionable information that leads to appropriate, safe and timely interventions without overwhelming outpatient cardiology and general medical practices. Future directions for implantable hemodynamic monitors beyond their utility in heart failure may include management of other major chronic diseases such as pulmonary hypertension, end stage renal disease and portal hypertension.

  13. Local Leak Detection and Health Monitoring of Pressurized Tanks

    Science.gov (United States)

    Polzin, Kurt; Witherow, William; Korman, Valentin; Sinko, John; Hendrickson, Adam

    2011-01-01

    An optical gas-detection sensor safely monitors pressurized systems (such as cryogenic tanks) and distribution systems for leaks. This sensor system is a fiber-coupled, solid optical body interferometer that allows for the miniaturized sensing element of the device to be placed in the smallest of recesses, and measures a wide range of gas species and densities (leaks). The deflection of the fringe pattern is detected and recorded to yield the time-varying gas density in the gap. This technology can be used by manufacturers or storage facilities with toxic, hazardous, or explosive gases. The approach is to monitor the change in the index of refraction associated with low-level gas leaks into a vacuum environment. The completion of this work will provide NASA with an enabling capability to detect gas system leaks in space, and to verify that pressurized systems are in a safe (i.e. non-leaking) condition during manned docking and transit operations. By recording the output of the sensor, a time-history of the leak can be constructed to indicate its severity. Project risk is mitigated by having several interferometric geometries and detection techniques available, each potentially leveraging hardware and lessons learned to enhance detectability.

  14. CSF-endorphines in acute and chronic brain lesions.

    Science.gov (United States)

    Hamel, E

    1988-01-01

    In order to answer the question of an opioid influence on consciousness, a radio-immuno-assay (n = 852) of beta-endorphin and beta-LPH (beta-lipotropic hormone) in both ventricular CSF and blood plasma was carried out in 101 neurosurgical patients. The following results were obtained: I) beta-END and beta-LPH levels were found to be lower in the CSF than in blood plasma. II) beta-END and beta-LPH in the CSF was the same in both sexes. III) beta-END levels in the CSF decreased with age. IV) beta-END and beta-LPH levels showed a diurnal rhythm with a maximum in the late a. m. hours. V) beta-END levels in the ventricular CSF tend to decrease parallel to a drop in conciousness as well as with longlasting comatous states. VI) beta-END in ventricular CSF becomes higher with increasing systolic arterial blood pressure. VII) beta-END and beta-LPH levels in ventricular CSF are not correlated with the type of the disease, CSF pressure, body temperature or respiratory changes.

  15. Diagnosis and therapeutic monitoring of inborn errors of creatine metabolism and transport using liquid chromatography-tandem mass spectrometry in urine, plasma and CSF.

    Science.gov (United States)

    Haas, Dorothea; Gan-Schreier, Hongying; Langhans, Claus-Dieter; Anninos, Alexandros; Haege, Gisela; Burgard, Peter; Schulze, Andreas; Hoffmann, Georg F; Okun, Jürgen G

    2014-03-15

    Biochemical detection of inborn errors of creatine metabolism or transport relies on the analysis of three main metabolites in biological fluids: guanidinoacetate (GAA), creatine (CT) and creatinine (CTN). Unspecific clinical presentation of the diseases might be the cause that only few patients have been diagnosed so far. We describe a LC-MS/MS method allowing fast and reliable diagnosis by simultaneous quantification of GAA, CT and CTN in urine, plasma and cerebrospinal fluid (CSF) and established reference values for each material. For quantification deuterated stable isotopes of each analyte were used as internal standards. GAA, CT and CTN were separated by reversed-phase HPLC. The characterization was carried out by scanning the ions of each compound by negative ion tandem mass spectrometry. Butylation is needed to achieve sufficient signal intensity for GAA and CT but it is not useful for analyzing CTN. The assay is linear in a broad range of analyte concentrations usually found in urine, plasma and CSF. Comparison of the "traditional" cation-exchange chromatography and LC-MS/MS showed proportional differences but linear relationships between the two methods. The described method is characterized by high speed and linearity over large concentration ranges comparable to other published LC-MS methods but with higher sensitivity for GAA and CT. In addition, we present the largest reference group ever published for guanidino compounds in all relevant body fluids. Therefore this method is applicable for high-throughput approaches for diagnosis and follow-up of inborn errors of creatine metabolism and transport.

  16. Accuracy of the Dinamap 1846 XT automated blood pressure monitor.

    Science.gov (United States)

    Beaubien, E R; Card, C M; Card, S E; Biem, H J; Wilson, T W

    2002-09-01

    Accurate blood pressure (BP) measurement is important for the detection and treatment of hypertension. Despite widespread use of automated devices, there is limited published evidence for their reliability and accuracy. To determine the reliability and accuracy of the Dinamap 1846XT (Critikon Corporation, Tampa, FL, USA), a commonly used non-invasive oscillometric BP monitor The Dinamap was evaluated against the mercury manometer in 70 randomly selected adult hospitalised medical patients. Each individual underwent three sets of standardised BP measurement by automated method and three sets by mercury manometer by two independent observers. Reliability of BP measurement was assessed by repeated measures analysis. Dinamap accuracy was evaluated according to the American Association of Medical Instrumentation (AAMI) and British Hypertension Society (BHS) guidelines. Most patients were either normotensive or had stage I hypertension. The Dinamap tended to overestimate lower diastolic BP, and displayed poor reliability (P mercury manometer and 84% of systolic and 80% of diastolic readings were within 10 mm hg (bhs grade c). systolic and diastolic accuracy were worse with pressures >160/90 mm Hg (grade D) although these measures were based on a smaller sample of subjects. In conclusion the Dinamap yields inaccurate estimates of both systolic and diastolic BP even under standardised, and thus optimal conditions. This inaccuracy is exaggerated at higher BP (>160/90 mm Hg), although the number of measurements at higher pressures was small. We recommend that this device not be used when accurate BP measurement is needed for therapeutic decision-making.

  17. Biotelemetric Wireless Intracranial Pressure Monitoring: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Mohammad H. Behfar

    2015-01-01

    Full Text Available Assessment of intracranial pressure (ICP is of great importance in management of traumatic brain injuries (TBIs. The existing clinically established ICP measurement methods require catheter insertion in the cranial cavity. This increases the risk of infection and hemorrhage. Thus, noninvasive but accurate techniques are attractive. In this paper, we present two wireless, batteryless, and minimally invasive implantable sensors for continuous ICP monitoring. The implants comprise ultrathin (50 μm flexible spiral coils connected in parallel to a capacitive microelectromechanical systems (MEMS pressure sensor. The implantable sensors are inductively coupled to an external on-body reader antenna. The ICP variation can be detected wirelessly through measuring the reader antenna’s input impedance. This paper also proposes novel implant placement to improve the efficiency of the inductive link. In this study, the performance of the proposed telemetry system was evaluated in a hydrostatic pressure measurement setup. The impact of the human tissues on the inductive link was simulated using a 5 mm layer of pig skin. The results from the in vitro measurement proved the capability of our developed sensors to detect ICP variations ranging from 0 to 70 mmHg at 2.5 mmHg intervals.

  18. Integrated landslide monitoring: rainfalls, pore water pressures and surface movements

    Science.gov (United States)

    Berti, M.; Casula, G.; Elmi, C.; Fabris, M.; Ghirotti, M.; Loddo, F.; Mora, P.; Pesci, A.; Simoni, A.

    2003-04-01

    Rainfall-induced landslides involving clay-rich soils are widely represented in the Apennines. They cover up to 30% of the slopes forming the relief constituted by chaotic clayey units and are typically subject to repeated reactivations of the movement which are often triggered by a series of discrete failures located in the upper part (headscarp). Failures and movement can then propagate downslope and reactivate the whole landslide deposit which displays a typical elongated body, limited depth and a fan-shaped toe as a result of successive slow earth-flow like movements. An experimental monitoring programme was designed and is currently operating on the Rocca Pitigliana landslide whose characteristics well represent the above described type of movements. Its last parossistic movement date back to 1999 and, since then, remedial works were realized on behalf of local authorities. They basically consist of surficial and deep drainage works located on the landslide body. Experimental activities focus on the main headscarp whose morphology and sub-surface water circulation scheme were unaffected by the interventions. The monitoring approach includes measuring rainfalls and pore-pressure responses in both saturated and unsaturated soils. Surficial movements are continuously measured by means of GPS permanent stations and by wire extensometers which allow real time control of headscarp activity. Main aim of the monitoring activities is to provide experimental data, which can be used to test various existing hydrologic models and to identify triggering conditions. Since the ‘70s, many hydrologic models have been proposed to describe the pore water pressure distribution within the soil and its response to precipitation. The topic has recently drawn growing attention because of the recognized importance in landslide triggering but still experimental data are very much needed in order to obtain and validate capable predicting tools. This is mostly due to the multiple and

  19. Accuracy of continuous noninvasive arterial pressure monitoring in living-liver donors during transplantation.

    Science.gov (United States)

    Araz, Coskun; Zeyneloglu, Pinar; Pirat, Arash; Veziroglu, Nukhet; Camkiran Firat, Aynur; Arslan, Gulnaz

    2015-04-01

    Hemodynamic monitoring is vital during liver transplant surgeries because distinct hemodynamic changes are expected. The continuous noninvasive arterial pressure (CNAP) monitor is a noninvasive device for continuous arterial pressure measurement by a tonometric method. This study compared continuous noninvasive arterial pressure monitoring with invasive direct arterial pressure monitoring in living-liver donors during transplant. There were 40 patients analyzed while undergoing hepatic lobectomy for liver transplant. Invasive pressure monitoring was established at the radial artery and continuous noninvasive arterial pressure monitoring using a finger sensor was recorded simultaneously from the contralateral arm. Systolic, diastolic, and mean arterial pressures from the 2 methods were compared. Correlation between the 2 methods was calculated. A total of 5433 simultaneous measurements were obtained. For systolic arterial blood pressure, 55% continuous noninvasive arterial pressure measurements were within 10% direct arterial measurement; the correlation was 0.479, continuous noninvasive arterial pressure bias was -0.3 mm Hg, and limits of agreement were 32.0 mm Hg. For diastolic arterial blood pressure, 50% continuous noninvasive arterial pressure measurements were within 10% direct arterial measurement; the correlation was 0.630, continuous noninvasive arterial pressure bias was -0.4 mm Hg, and limits of agreement were 21.1 mm Hg. For mean arterial blood pressure, 60% continuous noninvasive arterial pressure measurements were within 10% direct arterial measurement; the correlation was 0.692, continuous noninvasive arterial pressure bias was +0.4 mm Hg, and limits of agreement were 20.8 mm Hg. The 2 monitoring techniques did not show acceptable agreement. Our results suggest that continuous noninvasive arterial pressure monitoring is not equivalent to invasive arterial pressure monitoring in donors during living-donor liver transplant.

  20. [Monitoring of intra-abdominal pressure and abdominal perfusion pressure in urgent abdominal surgery].

    Science.gov (United States)

    Raĭbuzhis, E N; Fot, E V; Gaĭdukov, K M; Kirov, M Iu

    2014-01-01

    To evaluate the changes in intra-abdominal pressure (IAP) and abdominal perfusion pressure (APP) during perioperative period in urgent abdominal surgery and to assess the relationship of these parameters with gas exchange and tissue perfusion. Twenty-four patients undergoing emergency abdominal surgery were enrolled into a prospective observational study. We recorded IAP APP, mean arterial pressure, arterial and venous blood gases after induction of anesthesia, at the end of surgery, and 6, 12, 48 and 72 h postoperatively. LAP was measured by nasogastric tube using CiMON monitor (Pulsion Medical Systems, Germany). In addition, we studied the relationship of IAP and APP with blood gases parameters. We observed perioperative increase of IAP (> 12 mm Hg) in 75% of enrolled patients, tendency to postoperative rise of IAP and transient increase of arterial lactate at 6 h after surgery. APP remained within normal values. We found positive correlation of APP with PaO2/FiO2 and ScvO2 at 72 hours after surgery. Transient perioperative increase of IAP was observed in 75% patients undergoing urgent abdominal surgery; however in parallel with intensive care the abdominal perfusion pressure remained within normal values. Abdominal perfusion is related with arterial oxygenation and central venous saturation.

  1. Noninvasive Subharmonic Pressure Estimation for Monitoring Breast Cancer Response to Neoadjuvant Therapy

    Science.gov (United States)

    2013-01-01

    AD_________________ Award Number: W81XWH-08-1-0503 TITLE: Noninvasive Subharmonic Pressure...SUBTITLE 5a. CONTRACT NUMBER Noninvasive Subharmonic Pressure Estimation for Monitoring Breast Cancer Response to Neoadjuvant Therapy 5b. GRANT...SUBTITLE Noninvasive Subharmonic Pressure Estimation for Monitoring Breast Cancer 5. FUNDING NUMBERS W81XWH-08-1-0503 6. AUTHOR(S) Flemming

  2. Blood Pressure Mobile Monitoring for Pregnant Woman Based Android System

    Science.gov (United States)

    Supriyanti, Retno; Erfayanto, Uji; Ramadani, Yogi; Murdyantoro, Eko; Widodo, Haris B.

    2016-01-01

    Currently, at least 18,000 women die every year in Indonesia due to pregnancy or childbirth. It means that every half hour a woman dies due to pregnancy or childbirth. As a result, every year 36,000 children became orphans. The high maternal mortality rate was put Indonesia on top in ASEAN. The main causes of maternal mortality are high-risk pregnancy. Mothers who have diseases like high blood pressure, pre-eclampsia, diabetes, hyperthyroidism, and already over 40 years old and infectious diseases such as rubella, hepatitis and HIV can be factors that lead to high-risk pregnancy. This paper will discuss the development of a blood pressure monitoring device that is suitable for pregnant women. It is based on convenience for pregnant women to get the equipment that is flexible with her presence. Results indicate that the equipment is in use daily support for pregnant women therefore, one of the causes of maternal mortality can be detected earlier.

  3. Hindlimb Suspension (HLS) in Rodents for the Study of Intracranial Pressure, Molecular and Histologic Changes in the Eye, and CSF Production Regulation and Resorption: A Status Report of Two Studies

    Science.gov (United States)

    Theriot, C. A.; Taibbi, G.; Vizzeri, G.; Parsons-Wingerter, P.; Chevez-Barrios, P.; Rivera, A.; Zanello, S. B.

    2016-01-01

    This status report corresponds to two studies tied to an animal experiment being executed at the University of California Davis (Charles Fuller's laboratory). The animal protocol uses the well-documented rat hindlimb suspension (HLS) model, to examine the relationship between cephalic fluid shifts and the regulation of intracranial (ICP) and intraocular (IOP) pressures as well as visual system structure and function. Long Evans rats are subjected to HLS durations of 7, 14, 28 and 90 days. Subgroups of the 90-day animals are studied for recovery periods of 7, 14, 28 or 90 days. All HLS subjects have age-matched cage controls. Various animal cohorts are planned for this study: young males, young females and old males. In addition to the live measures (ICP by telemetry, IOP and retinal parameters by optical coherence tomography) which are shared with the Fuller study, the specific outcomes for this study include: -Gene expression analysis of the retina -Histologic analysis - Analysis of the microvasculature of retina flat mounts by NASA's VESsel GENeration Analysis (VESGEN) Software. To date, the young male and female cohorts are being completed. Due to the need to keep technical variation to a minimum, the histologic and genomic analyses have been delayed until all samples from each cohort are available and can be processed in a single batch per cohort. The samples received so far correspond to young males sacrificed at 7,14, 28 and 90 days of HLS and at 90 days of recovery; and from young females sacrificed at 7, 14 and 28 of HLS. A complementary study titled: "A gene expression and histologic approach to the study of cerebrospinal fluid (CSF) production and outflow in hindlimb suspended rats" seeks to study the molecular components of CSF production and outflow modulation as a result of HLS, bringing a molecular and histologic approach to investigate genome wide expression changes in the arachnoid villi and choroid plexus of HLS rats compared to rats in normal

  4. Mobile Personal Health System for Ambulatory Blood Pressure Monitoring

    Directory of Open Access Journals (Sweden)

    Luis J. Mena

    2013-01-01

    Full Text Available The ARVmobile v1.0 is a multiplatform mobile personal health monitor (PHM application for ambulatory blood pressure (ABP monitoring that has the potential to aid in the acquisition and analysis of detailed profile of ABP and heart rate (HR, improve the early detection and intervention of hypertension, and detect potential abnormal BP and HR levels for timely medical feedback. The PHM system consisted of ABP sensor to detect BP and HR signals and smartphone as receiver to collect the transmitted digital data and process them to provide immediate personalized information to the user. Android and Blackberry platforms were developed to detect and alert of potential abnormal values, offer friendly graphical user interface for elderly people, and provide feedback to professional healthcare providers via e-mail. ABP data were obtained from twenty-one healthy individuals (>51 years to test the utility of the PHM application. The ARVmobile v1.0 was able to reliably receive and process the ABP readings from the volunteers. The preliminary results demonstrate that the ARVmobile 1.0 application could be used to perform a detailed profile of ABP and HR in an ordinary daily life environment, bedsides of estimating potential diagnostic thresholds of abnormal BP variability measured as average real variability.

  5. Soft wearable contact lens sensor for continuous intraocular pressure monitoring.

    Science.gov (United States)

    Chen, Guo-Zhen; Chan, Ion-Seng; Leung, Leo K K; Lam, David C C

    2014-09-01

    Intraocular pressure (IOP) is a primary indicator of glaucoma, but measurements from a single visit to the clinic miss the peak IOP that may occur at night during sleep. A soft chipless contact lens sensor that allows the IOP to be monitored throughout the day and at night is developed in this study. A resonance circuit composed of a thin film capacitor coupled with a sensing coil that can sense corneal curvature deformation is designed, fabricated and embedded into a soft contact lens. The resonance frequency of the sensor is designed to vary with the lens curvature as it changes with the IOP. The frequency responses and the ability of the sensor to track IOP cycles were tested using a silicone rubber model eye. The results showed that the sensor has excellent linearity with a frequency response of ∼8 kHz/mmHg, and the sensor can accurately track fluctuating IOP. These results showed that the chipless contact lens sensor can potentially be used to monitor IOP to improve diagnosis accuracy and treatment of glaucoma.

  6. Ambulatory blood pressure monitoring in healthy children with parental hypertension.

    Science.gov (United States)

    Alpay, Harika; Ozdemir, Nihal; Wühl, Elke; Topuzoğlu, Ahmet

    2009-01-01

    The aim of this study was to compare ambulatory blood pressure monitoring (ABPM) parameters in offspring with at least one hypertensive parent (HP) to offspring with normotensive parents (NP) and to determine whether gender of parent or child might influence the association between parental hypertension and blood pressure (BP). Eighty-nine healthy children (mean age 11.1 +/- 3.9 years) with HP and 90 controls (mean age 10.5 +/- 3.1 years) with NP were recruited. Age, gender, and height did not differ between the two groups, whereas children of HP had higher weight, body mass index (BMI), and waist circumference compared with healthy controls. No difference was found in casual BP between the two groups. In contrast, during ABPM daytime and nighttime mean systolic and diastolic BP and mean arterial pressure (MAP) standard deviation scores (SDS) were significantly elevated in children with HP. The mean percentage of nocturnal BP decline (dipping) was not significantly different between the two groups. Children with hypertensive mothers had higher daytime systolic and MAP SDS than controls; no such difference was detected for children with hypertensive fathers. Daytime systolic and MAP SDS were significantly elevated in boys with HP compared with boys with NP but failed to be significant in girls. Multiple linear regression analysis showed that parental history of hypertension (B = 0.29) and BMI (B = 0.03) were independently correlated with increase of daytime MAP SDS. Early changes in ambulatory BP parameters were present in healthy children of HP. BP in HP offspring was influenced by the gender of the affected parent and the offspring.

  7. Complications corner: Anterior thoracic disc surgery with dural tear/CSF fistula and low-pressure pleural drain led to severe intracranial hypotension

    Directory of Open Access Journals (Sweden)

    Eline A Oudeman

    2015-01-01

    Conclusion: Severe neurological deterioration occurring after thoracic decompressive surgery may rarely be attributed to intracranial hypotension due to a subarachnoid-pleural fistula. Patients should be treated with external lumbar drainage of cerebrospinal fluid for 3-5 days rather than a low-pressure pleural drain to avoid the onset of intracranial hypotension leading to symptomatic subdural hematomas.

  8. A 2013 Survey on Pressure Monitoring in Adult Cardiopulmonary Bypass Circuits: Modes and Applications

    OpenAIRE

    Rigg, Laura; Searles, Bruce; Darling, Edward Morse

    2014-01-01

    Pressure data acquired from multiple sites of extracorporeal circuits can be an important parameter to monitor for the safe conduct of cardiopulmonary bypass (CPB). Although previous surveys demonstrate that CPB circuit pressure monitoring is widely used, there are very little data cataloging specific applications of this practice. Therefore, the purpose of this study is to survey the perfusion community to catalog 1) primary CPB circuit site pressure monitoring locations; 2) type of manomete...

  9. A 2013 Survey on Pressure Monitoring in Adult Cardiopulmonary Bypass Circuits: Modes and Applications.

    Science.gov (United States)

    Rigg, Laura; Searles, Bruce; Darling, Edward Morse

    2014-12-01

    Pressure data acquired from multiple sites of extracorporeal circuits can be an important parameter to monitor for the safe conduct of cardiopulmonary bypass (CPB). Although previous surveys demonstrate that CPB circuit pressure monitoring is widely used, there are very little data cataloging specific applications of this practice. Therefore, the purpose of this study is to survey the perfusion community to catalog 1) primary CPB circuit site pressure monitoring locations; 2) type of manometers used; 3) pressure monitoring interface and servoregulation with pump console; and 4) the rationale and documentation associated with pressure monitoring during CPB. In June 2013, a validated 27-question online survey was sent directly through an e-mail link to the chief perfusionists in the northeast United States. Completed surveys were received from 75 of 117 surveys deployed yielding a 64% response rate. Arterial line pressure monitoring during CPB is reported by 99% with six distinct circuit site locations identified. Cardioplegia system pressure was monitored by 95% of the centers. For vacuum-assisted venous drainage (VAVD) users, the venous pressure was measured by 72% of the responding centers. Arterial line pressure servoregulation of the arterial pump was indicated by 61% of respondents and 75% of centers record arterial line pressure in their perfusion record. Most centers (77%) report the use of a transducer that is integrated into the pump console providing a digital pressure display, whereas 20% combine an aneroid gauge manometer with the integrated digital transducer. This study demonstrates that the practice of arterial line pressure monitoring during CPB is nearly universal. However, the selection of the pressure monitoring site on the circuit, modes of monitoring pressure, and their applications are highly variable across the perfusion community.

  10. Lack of relationship between resistance to cerebrospinal fluid outflow and intracranial pressure in normal pressure hydrocephalus.

    Science.gov (United States)

    Eide, P K; Fremming, A D; Sorteberg, A

    2003-12-01

    To explore whether calculation of resistance to cerebrospinal fluid (CSF) outflow (Rout) by the lumbar constant rate infusion test in a reliable way predicts the intracranial pressure (ICP) profile in normal pressure hydrocephalus (NPH). A prospective study was undertaken including 16 cases with clinical signs of normal pressure hydrocephalus that were investigated with both continuous ICP monitoring and the lumbar constant rate infusion test. Intracranial pressure monitoring was performed for about 24 h, and supplied with a simultaneous lumbar constant rate infusion test at the end of the monitoring period. The pressure recordings were analysed using the Sensometrics Pressure Analyser. Various characteristics of the pressure curves were compared. The continuous ICP recordings were considered as normal (mean ICP or =12.0 mmHg/ml/min) in 12 of 16 cases. There was no relationship between lumbar Rout and mean ICP during sleep. We could not find any relationship between lumbar Rout and number of nightly ICP elevations of 1525 mmHg lasting 0.5 or 1 min. Neither resistance to CSF outflow (Rout) nor mean ICP during sleep was related to the ventricular size. The results of this prospective study revealed no significant relationship between resistance to CSF outflow (Rout) and the ICP profile in NPH cases. The results also suggest that caution should be made when predicting the ICP profile on the basis of measuring the lumbar CSF pressure for a few minutes duration.

  11. Accuracy of invasive arterial pressure monitoring in cardiovascular patients: an observational study

    National Research Council Canada - National Science Library

    Romagnoli, Stefano; Ricci, Zaccaria; Quattrone, Diego; Tofani, Lorenzo; Tujjar, Omar; Villa, Gianluca; Romano, Salvatore M; De Gaudio, A Raffaele

    2014-01-01

    Critically ill patients and patients undergoing high-risk and major surgery, are instrumented with intra-arterial catheters and invasive blood pressure is considered the "gold standard" for arterial pressure monitoring...

  12. Modalities of Invasive Arterial Pressure Monitoring in Critically Ill Patients: A Prospective Observational Study

    National Research Council Canada - National Science Library

    Jacq, Gwenaëlle; Gritti, Karine; Carré, Cécile; Fleury, Nadège; Lang, Annie; Courau-Courtois, Josette; Bedos, Jean-Pierre; Legriel, Stephane

    2015-01-01

    Few studies assessed modalities of invasive arterial pressure monitoring (IAPM). We evaluated effects on measured values of various combinations of transducer level, catheter access site, and patient position...

  13. Molecular CsF 5 and CsF 2 +

    KAUST Repository

    Rogachev, Andrey Yu.

    2015-06-03

    D5h star-like CsF5, formally isoelectronic with known XeF5− ion, is computed to be a local minimum on the potential energy surface of CsF5, surrounded by reasonably large activation energies for its exothermic decomposition to CsF+2 F2, or to CsF3 (three isomeric forms)+F2, or for rearrangement to a significantly more stable isomer, a classical Cs+ complex of F5−. Similarly the CsF2+ ion is computed to be metastable in two isomeric forms. In the more symmetrical structures of these molecules there is definite involvement in bonding of the formally core 5p levels of Cs.

  14. Peripheral arterial blood pressure monitoring adequately tracks central arterial blood pressure in critically ill patients: an observational study

    OpenAIRE

    Mignini, Mariano Alejandro; Piacentini, Enrique; Dubin,Arnaldo

    2006-01-01

    Introduction Invasive arterial blood pressure monitoring is a common practice in intensive care units (ICUs). Accuracy of invasive blood pressure monitoring is crucial in evaluating the cardiocirculatory system and adjusting drug therapy for hemodynamic support. However, the best site for catheter insertion is controversial. Lack of definitive information in critically ill patients makes it difficult to establish guidelines for daily practice in intensive care. We hypothesize that peripheral ...

  15. Choking under monitoring pressure: being watched by the experimenter reduces executive attention.

    Science.gov (United States)

    Belletier, Clément; Davranche, Karen; Tellier, Idriss S; Dumas, Florence; Vidal, Franck; Hasbroucq, Thierry; Huguet, Pascal

    2015-10-01

    Performing more poorly given one's skill level ("choking") is likely in situations that offer an incentive if a certain outcome is achieved (outcome pressure) or when one is being watched by others-especially when one's performance is being evaluated (monitoring pressure). According to the choking literature, outcome pressure is associated with reduced executive control of attention, whereas monitoring pressure is associated with increased, yet counterproductive, attention to skill processes. Here, we show the first evidence that monitoring pressure-being watched by the experimenter-may lead individuals with higher working memory to choke on a classic measure of executive control-just the task effect thought to result from outcome pressure. Not only does this finding help refine our understanding of the processes underlying choking under monitoring pressure, but it also leads to a new look at classic audience effects, with an important implication for experimental psychology.

  16. Twenty-Four-Hour Ambulatory Blood Pressure Monitoring in Hypertension

    Science.gov (United States)

    2012-01-01

    Executive Summary Objective The objective of this health technology assessment was to determine the clinical effectiveness and cost-effectiveness of 24-hour ambulatory blood pressure monitoring (ABPM) for hypertension. Clinical Need: Condition and Target Population Hypertension occurs when either systolic blood pressure, the pressure in the artery when the heart contracts, or diastolic blood pressure, the pressure in the artery when the heart relaxes between beats, are consistently high. Blood pressure (BP) that is consistently more than 140/90 mmHg (systolic/diastolic) is considered high. A lower threshold, greater than 130/80 mmHg (systolic/diastolic), is set for individuals with diabetes or chronic kidney disease. In 2006 and 2007, the age-standardized incidence rate of diagnosed hypertension in Canada was 25.8 per 1,000 (450,000 individuals were newly diagnosed). During the same time period, 22.7% of adult Canadians were living with diagnosed hypertension. A smaller proportion of Canadians are unaware they have hypertension; therefore, the estimated number of Canadians affected by this disease may be higher. Diagnosis and management of hypertension are important, since elevated BP levels are related to the risk of cardiovascular disease, including stroke. In Canada in 2003, the costs to the health care system related to the diagnosis, treatment, and management of hypertension were over $2.3 billion (Cdn). Technology The 24-hour ABPM device consists of a standard inflatable cuff attached to a small computer weighing about 500 grams, which is worn over the shoulder or on a belt. The technology is noninvasive and fully automated. The device takes BP measurements every 15 to 30 minutes over a 24-to 28-hour time period, thus providing extended, continuous BP recordings even during a patient’s normal daily activities. Information on the multiple BP measurements can be downloaded to a computer. The main detection methods used by the device are auscultation and

  17. A Wireless Pressure Sensor for Continuous Monitoring of Intraocular Pressure in Conscious Animals.

    Science.gov (United States)

    Bello, Simon A; Passaglia, Christopher L

    2017-08-15

    An important aspect of eye health in humans and animal models of human diseases is intraocular pressure (IOP). IOP is typically measured by hand with a tonometer, so data are sparse and sporadic and round-the-clock variations are not well characterized. Here we present a novel system for continuous wireless IOP and temperature measurement in small animals. The system consists of a cannula implanted in the anterior chamber of the eye connected to pressure sensing electronics that can be worn by rats or implanted in larger mammals. The system can record IOP with 0.3 mmHg accuracy and negligible drift at a rate of 0.25 Hz for 1-2 months on a regulated battery or indefinitely at rates up to 250 Hz via RF energy harvesting. Chronic recordings from conscious rats showed that IOP follows a diurnal rhythm, averaging 16.5 mmHg during the day and 21.7 mmHg at night, and that the IOP rhythm lags a diurnal rhythm in body temperature by 2.1 h. IOP and body temperature fluctuations were positively correlated from moment-to-moment as well. This technology allows researchers to monitor for the first time the precise IOP history of rat eyes, a popular model for glaucoma studies.

  18. Chemokines in CSF of Alzheimer's disease patients

    Directory of Open Access Journals (Sweden)

    Jôice Dias Corrêa

    2011-06-01

    Full Text Available Some studies have linked the presence of chemokines to the early stages of Alzheimer's disease (AD. Then, the identification of these mediators may contribute to diagnosis. Our objective was to evaluate the levels of beta-amyloid (BA, tau, phospho-tau (p-tau and chemokines (CCL2, CXCL8 and CXCL10 in the cerebrospinal fluid (CSF of patients with AD and healthy controls. The correlation of these markers with clinical parameters was also evaluated. The levels of p-tau were higher in AD compared to controls, while the tau/p-tau ratio was decreased. The expression of CCL2 was increased in AD. A positive correlation was observed between BA levels and all chemokines studied, and between CCL2 and p-tau levels. Our results suggest that levels of CCL2 in CSF are involved in the pathogenesis of AD and it may be an additional useful biomarker for monitoring disease progression.

  19. CSF Biomarkers for Alzheimer's Disease Diagnosis

    Directory of Open Access Journals (Sweden)

    A. Anoop

    2010-01-01

    Full Text Available Alzheimer's disease (AD is the most common form of dementia that affects several million people worldwide. The major neuropathological hallmarks of AD are the presence of extracellular amyloid plaques that are composed of Aβ40 and Aβ42 and intracellular neurofibrillary tangles (NFT, which is composed of hyperphosphorylated protein Tau. While the amyloid plaques and NFT could define the disease progression involving neuronal loss and dysfunction, significant cognitive decline occurs before their appearance. Although significant advances in neuroimaging techniques provide the structure and physiology of brain of AD cases, the biomarker studies based on cerebrospinal fluid (CSF and plasma represent the most direct and convenient means to study the disease progression. Biomarkers are useful in detecting the preclinical as well as symptomatic stages of AD. In this paper, we discuss the recent advancements of various biomarkers with particular emphasis on CSF biomarkers for monitoring the early development of AD before significant cognitive dysfunction.

  20. European Society of Hypertension practice guidelines for ambulatory blood pressure monitoring

    NARCIS (Netherlands)

    Parati, Gianfranco; Stergiou, George; O'Brien, Eoin; Asmar, Roland; Beilin, Lawrence; Bilo, Grzegorz; Clement, Denis; de la Sierra, Alejandro; de Leeuw, Peter; Dolan, Eamon; Fagard, Robert; Graves, John; Head, Geoffrey A; Imai, Yutaka; Kario, Kazuomi; Lurbe, Empar; Mallion, Jean-Michel; Mancia, Giuseppe; Mengden, Thomas; Myers, Martin; Ogedegbe, Gbenga; Ohkubo, Takayoshi; Omboni, Stefano; Palatini, Paolo; Redon, Josep; Ruilope, Luis M; Shennan, Andrew; Staessen, Jan A; vanMontfrans, Gert; Verdecchia, Paolo; Waeber, Bernard; Wang, Jiguang; Zanchetti, Alberto; Zhang, Yuqing

    2014-01-01

    Given the increasing use of ambulatory blood pressure monitoring (ABPM) in both clinical practice and hypertension research, a group of scientists, participating in the European Society of Hypertension Working Group on blood pressure monitoring and cardiovascular variability, in year 2013 published

  1. Does home blood pressure monitoring improve patient outcomes? A systematic review comparing home and ambulatory blood pressure monitoring on blood pressure control and patient outcomes

    Directory of Open Access Journals (Sweden)

    Breaux-Shropshire TL

    2015-07-01

    Full Text Available Tonya L Breaux-Shropshire,1,2 Eric Judd,1 Lee A Vucovich,3 Toneyell S Shropshire,4 Sonal Singh5 1Vascular Biology and Hypertension Program, Cardiovascular Disease, School of Medicine, University of Alabama at Birmingham, Birmingham, AL, USA; 2Veterans Administration, Birmingham, AL, USA; 3Lister Hill Library, University of Alabama at Birmingham, Birmingham, AL, USA; 4Department of Physical Therapy, Louisiana State University Health Sciences Center, New Orleans, LA, USA; 5Department of Medicine, John Hopkins School of Medicine, Baltimore, MD, USA Objective: Our objective was to compare the clinical effectiveness of home blood pressure monitoring (HBPM and 24-hour ambulatory blood pressure monitoring (ABPM on blood pressure (BP control and patient outcomes. Design: A systematic review was conducted. We also appraised the methodological quality of studies. Data sources: PubMed, Scopus, CINAHL, and the Cochrane Central Register of Control Trials (CENTRAL. Inclusion criteria: Randomized control trials, prospective and retrospective cohort studies, observational studies, and case-control studies published in English from any year to present that describe HBPM and 24-hour ABPM and report on systolic and/or diastolic BP and/or heart attack, stroke, kidney failure and/or all-cause mortality for adult patients. Due to the nature of the question, studies with only untreated patients were not considered. Results: Of 1,742 titles and abstractions independently reviewed by two reviewers, 137 studies met predetermined criteria for evaluation. Nineteen studies were identified as relevant and included in the paper. The common themes were that HBPM and ABPM correlated with cardiovascular events and mortality, and targeting HBPM or ABPM resulted in similar outcomes. Associations between BP measurement type and mortality differed by study population. Both the low sensitivity of office blood pressure monitoring (OBPM to detect optimal BP control by ABPM and the

  2. Wearable Beat to Beat Blood Pressure Monitor Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A key component of NASA's human exploration programs is a system that monitors the health of the crew during the space missions. The wearable physiological monitor...

  3. Brachial Arterial Pressure Monitoring during Cardiac Surgery Rarely Causes Complications.

    Science.gov (United States)

    Singh, Asha; Bahadorani, Bobby; Wakefield, Brett J; Makarova, Natalya; Kumar, Priya A; Tong, Michael Zhen-Yu; Sessler, Daniel I; Duncan, Andra E

    2017-06-01

    Brachial arterial catheters better estimate aortic pressure than radial arterial catheters but are used infrequently because complications in a major artery without collateral flow are potentially serious. However, the extent to which brachial artery cannulation promotes complications remains unknown. The authors thus evaluated a large cohort of cardiac surgical patients to estimate the incidence of related serious complications. The institutional Society of Thoracic Surgeons Adult Cardiac Surgery Database and Perioperative Health Documentation System Registry of the Cleveland Clinic were used to identify patients who had brachial artery cannulation between 2007 and 2015. Complications within 6 months after surgery were identified by International Classification of Diseases, Ninth Revision diagnostic and procedural codes, Current Procedural Terminology procedure codes, and Society of Thoracic Surgeons variables. The authors reviewed electronic medical records to confirm that putative complications were related plausibly to brachial arterial catheterization. Complications were categorized as (1) vascular, (2) peripheral nerve injury, or (3) infection. The authors evaluated associations between brachial arterial complications and patient comorbidities and between complications and in-hospital mortality and duration of hospitalization. Among 21,597 qualifying patients, 777 had vascular or nerve injuries or local infections, but only 41 (incidence 0.19% [95% CI, 0.14 to 0.26%]) were potentially consequent to brachial arterial cannulation. Vascular complications occurred in 33 patients (0.15% [0.10 to 0.23%]). Definitely or possibly related infection occurred in 8 (0.04% [0.02 to 0.08%]) patients. There were no plausibly related neurologic complications. Peripheral arterial disease was associated with increased risk of complications. Brachial catheter complications were associated with prolonged hospitalization and in-hospital mortality. Brachial artery cannulation for

  4. Peripheral arterial blood pressure monitoring adequately tracks central arterial blood pressure in critically ill patients: an observational study.

    Science.gov (United States)

    Mignini, Mariano Alejandro; Piacentini, Enrique; Dubin, Arnaldo

    2006-01-01

    Invasive arterial blood pressure monitoring is a common practice in intensive care units (ICUs). Accuracy of invasive blood pressure monitoring is crucial in evaluating the cardiocirculatory system and adjusting drug therapy for hemodynamic support. However, the best site for catheter insertion is controversial. Lack of definitive information in critically ill patients makes it difficult to establish guidelines for daily practice in intensive care. We hypothesize that peripheral and central mean arterial blood pressures are interchangeable in critically ill patients. This is a prospective, observational study carried out in a surgical-medical ICU in a teaching hospital. Fifty-five critically ill patients with clinical indication of invasive arterial pressure monitoring were included in the study. No interventions were made. Simultaneous measurements were registered in central (femoral) and peripheral (radial) arteries. Bias and precision between both measurements were calculated with Bland-Altman analysis for the whole group. Bias and precision were compared between patients receiving high doses of vasoactive drugs (norepinephrine or epinephrine >0.1 microg/kg/minute or dopamine >10 microg/kg/minute) and those receiving low doses (norepinephrine or epinephrine arterial pressure was 3 +/- 4 mmHg higher than peripheral mean arterial pressure for the whole population and there were no differences between groups (3 +/- 4 mmHg for both groups). Measurement of mean arterial blood pressure in radial or femoral arteries is clinically interchangeable. It is not mandatory to cannulate the femoral artery, even in critically ill patients receiving high doses of vasoactive drugs.

  5. Comprehensive Soldier Fitness (CSF) Experiment: Research Biases in the Development of the CSF

    Science.gov (United States)

    2013-06-13

    and teens can compare, and ultimately be transposed through the CSF, to developing resiliency of deployed Soldiers in combat zones. These studies...added pressure of a shortened development time may contribute to unintended biases or unmitigated biases. This study will look at all of their...units. They recommended that the units designate proponents to manage the suicide prevention program, maintain vigilance by leaders and Soldier peers

  6. Accuracy in Blood Pressure Monitoring: The Effect of Noninvasive Blood Pressure Cuff Inflation on Intra-arterial Blood Pressure Values.

    Science.gov (United States)

    Sheshadri, Veena; Tiwari, Akhilesh Kumar; Nagappa, Mahesh; Venkatraghavan, Lashmi

    2017-01-01

    Both invasive and noninvasive blood pressure (invasive arterial blood pressure [IABP] and noninvasive BP [NIBP]) monitors are used perioperatively; however, they often produce different values. The reason for this discrepancy is not clear, and it is possible that the act of cuff inflation itself might affect the IABP values, especially with the recurrent cycling of NIBP cuff. The aim of this study was to determine the effect of ipsilateral NIBP cuff inflation on the contralateral IABP values. Prospective, observational study. One hundred consecutive patients were studied. The NIBP device was set to cycle every 5 min for a total of 6 times. During each cuff inflation cycle, changes in IABP values from the arterial line in the contralateral arm were recorded. A total of 582 measurements were included for data analysis. Chi-square, paired t-test, analysis of variance. Mean (± standard deviation) changes in systolic BP (SBP), diastolic BP, and mean BP with cuff inflation were 6.7 ± 5.9, 2.6 ± 4.0, and 4.0 ± 3.9 mmHg, respectively. We observed an increase of 0-10 mmHg in SBP in majority (73.4%) of cuff inflations. The changes in IABP did not differ between the patients with or without hypertension or with the baseline SBP. This study showed that there is a transient reactive rise in IABP values with NIBP cuff inflation. This is important information in the perioperative and intensive care settings, where both these measurement techniques are routinely used. The exact mechanism for this effect is not known but may be attributed to the pain and discomfort from cuff inflation.

  7. Noninvasive 24-hour ambulatory arterial blood pressure monitoring in cirrhosis

    DEFF Research Database (Denmark)

    Møller, Søren; Wiinberg, N; Henriksen, Jens Henrik

    1995-01-01

    Cirrhotic patients have disturbed systemic hemodynamics with reduced arterial blood pressure, but this has not been investigated during daily activity and sleep. Systolic (SBP), diastolic (DBP), and mean arterial blood pressure (MAP), and heart rate (HR) were measured by an automatic ambulant...

  8. Tissue electrical properties monitoring for the prevention of pressure sore.

    Science.gov (United States)

    Ching, Congo Tak-Shing; Chou, Mei-Yun; Jiang, Siou-Jhen; Huang, Su-Hua; Sun, Tai-Ping; Liu, Wei-Hao; Liu, Chia-Ming

    2011-12-01

    Pressure sores are a significant problem in the healthcare sector. Although they may cause considerable morbidity, they are preventable. The objectives of this study are to (1) investigate the electrical properties of a tissue close to and away from the pressure sore site, and (2) establish a new approach for objective, reliable, low-cost and noninvasive screening or detection of pressure sore in its early stage. Randomised controlled trial. Fifteen patients participated in this study. They all had stage I or stage II sacral pressure sores. Tiny surface electrodes in four-electrode configuration were used for all tissue electrical properties measurements recorded over the frequency range of 30-10 MHz. Intraclass correlation coefficient (ICC) showed that all measurements (ICC > 0.90 for all measurements) had good reliability and validity. The real part of impedance (R) and the imaginary part of impedance (X) of a tissue measured close to the pressure sore site was found to be significantly smaller (p pressure sore site at a specific frequency range (R: 30.00-38.55 Hz; X: 43.95-606.40 Hz). It was also found that the extracellular resistance (R(e)) and the ratio of extracellular resistance to intracellular resistance (R(e)/R(i)) of a tissue measured close to the pressure sore site were significantly smaller (p pressure sore site. Since the electrical properties (R, X, R(e), R(e)/R(i) ) of a tissue close to, and away from, the pressure sore site can be significantly distinguished, a potentially promising method for the screening of pressure sores at an early stage has been proposed.

  9. Drift velocity and pressure monitoring of the CMS muon drift chambers

    CERN Document Server

    Sonnenschein, Lars

    2010-01-01

    The drift velocity in drift tubes of the CMS muon chambers is a key parameter for the muon track reconstruction and trigger. It needs to be monitored precisely in order to detect any deviation from its nominal value. A change in absolute pressure, a variation of the gas admixture or a contamination of the chamber gas by air affect the drift velocity. Furthermore, the temperature and magnetic field influence its value. First data, taken with a dedicated Velocity Drift Chamber (VDC) built by RWTH Aachen IIIA are presented. Another important parameter to be monitored is the pressure inside the muon drift tube chambers because the drift velocity depends on it. Furthermore the differential pressure must not exceed a certain value and the absolute pressure has to be kept slightly above ambient pressure to prevent air from entering into the muon drift tube chambers in case of a leak. Latest pressure monitoring results are discussed.

  10. "Flow comp off": An easy technique to confirm CSF flow within syrinx and aqueduct

    Directory of Open Access Journals (Sweden)

    Anitha Sen

    2013-01-01

    Full Text Available Flow compensation, a gradient pulse used for artifact reduction, often used to suppress cerebrospinal fluid (CSF flow artifacts in spinal magnetic resonance imaging (MRI, can be switched off to make the CSF flow voids within syrinx (syringomyelia and within aqueduct [normal pressure hydrocephalus (NPH] more obvious (thus confirming CSF flow. It is a simple method which does not require much time or expertise.

  11. Data Of Daily Blood Pressure Monitoring In Patients With Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    A.P. Rebrov

    2009-06-01

    Full Text Available The aim of present work is to study the frequency of hypertension and the peculiarity of 24-hour blood pressure monitoring in patients with rheumatoid arthritis. We studied 584 patients with rheumatoid arthritis. Daily blood pressure monitoring was carried out in 46 patients with arthritis and 18 patients with essential hypertension. Frequency of hypertension was higher in patients with arthritis then in general population. Elevation of systolic blood pressure, heart rate and arterial blood pressure adequate decrease at night were developed to associate with advance of the disease.

  12. Elevated CSF outflow resistance associated with impaired lymphatic CSF absorption in a rat model of kaolin-induced communicating hydrocephalus

    Directory of Open Access Journals (Sweden)

    Li Jie

    2010-02-01

    Full Text Available Abstract Background We recently reported a lymphatic cerebrospinal fluid (CSF absorption deficit in a kaolin model of communicating hydrocephalus in rats with ventricular expansion correlating negatively with the magnitude of the impediment to lymphatic function. However, it is possible that CSF drainage was not significantly altered if absorption at other sites compensated for the lymphatic defect. The purpose of this study was to investigate the impact of the lymphatic absorption deficit on global CSF absorption (CSF outflow resistance. Methods Kaolin was injected into the basal cisterns of Sprague Dawley rats. The development of hydrocephalus was assessed using magnetic resonance imaging (MRI. In one group of animals at about 3 weeks after injection, the movement of intraventricularly injected iodinated human serum albumin (125I-HSA into the olfactory turbinates provided an estimate of CSF transport through the cribriform plate into nasal lymphatics (n = 18. Control animals received saline in place of kaolin (n = 10. In a second group at about 3.5 weeks after kaolin injection, intraventricular pressure was measured continuously during infusion of saline into the spinal subarachnoid space at various flow rates (n = 9. CSF outflow resistance was calculated as the slope of the steady-state pressure versus flow rate. Control animals for this group either received no injections (intact: n = 11 or received saline in place of kaolin (n = 8. Results Compared to saline injected controls, lateral ventricular volume in the kaolin group was significantly greater (0.087 ± 0.013 ml, n = 27 versus 0.015 ± 0.001 ml, n = 17 and lymphatic function was significantly less (2.14 ± 0.72% injected/g, n = 18 versus 6.38 ± 0.60% injected/g, n = 10. Additionally, the CSF outflow resistance was significantly greater in the kaolin group (0.46 ± 0.04 cm H2O.μL-1.min, n = 9 than in saline injected (0.28 ± 0.03 cm H2O.μL-1.min, n = 8 or intact animals (0.18 ± 0

  13. Get the Most Out of Home Blood Pressure Monitoring

    Science.gov (United States)

    ... monitors might not give you an accurate reading. Most pharmacies, medical supply stores and some websites sell ... fitted on the upper arm are generally the most accurate. If you can't find a cuff ...

  14. Tyre pressure monitoring using a dynamical model-based estimator

    Science.gov (United States)

    Reina, Giulio; Gentile, Angelo; Messina, Arcangelo

    2015-04-01

    In the last few years, various control systems have been investigated in the automotive field with the aim of increasing the level of safety and stability, avoid roll-over, and customise handling characteristics. One critical issue connected with their integration is the lack of state and parameter information. As an example, vehicle handling depends to a large extent on tyre inflation pressure. When inflation pressure drops, handling and comfort performance generally deteriorate. In addition, it results in an increase in fuel consumption and in a decrease in lifetime. Therefore, it is important to keep tyres within the normal inflation pressure range. This paper introduces a model-based approach to estimate online tyre inflation pressure. First, basic vertical dynamic modelling of the vehicle is discussed. Then, a parameter estimation framework for dynamic analysis is presented. Several important vehicle parameters including tyre inflation pressure can be estimated using the estimated states. This method aims to work during normal driving using information from standard sensors only. On the one hand, the driver is informed about the inflation pressure and he is warned for sudden changes. On the other hand, accurate estimation of the vehicle states is available as possible input to onboard control systems.

  15. An improved flexible telemetry system to autonomously monitor sub-bandage pressure and wound moisture

    National Research Council Canada - National Science Library

    Mehmood, Nasir; Hariz, Alex; Templeton, Sue; Voelcker, Nicolas H

    2014-01-01

    This paper presents the development of an improved mobile-based telemetric dual mode sensing system to monitor pressure and moisture levels in compression bandages and dressings used for chronic wound management...

  16. Intracranial pressure and conductance to outflow of cerebrospinal fluid in normal-pressure hydrocephalus.

    Science.gov (United States)

    Børgesen, S E; Gjerris, F; Sørensen, S C

    1979-04-01

    Forty patients with clinical evidence of normal-pressure hydrocephalus were studied by monitoring intraventricular pressure during a 24-hour period, and by a lumboventricular perfusion test for measurement of the conductance to outflow of cerebrospinal fluid (CSF). The purpose of the study was to investigate whether there is a relationship between intraventricular pressure and conductance to outflow of CSF, and whether it is possible to use the results from pressure monitoring in the selection of patients who may be expected to benefit from shunting therapy. The conductance to outflow was used as an evaluation factor in the selection of patients to be treated by a shunt. The conductance to CSF outflow differed by twelvefold between the lowest and highest values. The level of resting intraventricular pressure was within normal limits in all patients. Accordingly, there was no evidence of a relationship between conductance to outflow and intraventricular pressure. So-called B-waves were seen more frequently in patients with decreased conductance to outflow, but were also present in patients with high conductance to outflow. Therefore, the presence of B-waves does not imply a low conductance to outflow of CSF.

  17. Packaged Capacitive Pressure Sensor System for Aircraft Engine Health Monitoring

    Science.gov (United States)

    Scardelletti, Maximilian C.; Zorman, Christian A.

    2016-01-01

    This paper describes the development of a packaged silicon carbide (SiC) based MEMS pressure sensor system designed specifically for a conventional turbofan engine. The electronic circuit is based on a Clapp-type oscillator that incorporates a 6H-SiC MESFET, a SiCN MEMS capacitive pressure sensor, titanate MIM capacitors, wirewound inductors, and thick film resistors. The pressure sensor serves as the capacitor in the LC tank circuit, thereby linking pressure to the resonant frequency of the oscillator. The oscillator and DC bias circuitry were fabricated on an alumina substrate and secured inside a metal housing. The packaged sensing system reliably operates at 0 to 350 psi and 25 to 540C. The system has a pressure sensitivity of 6.8 x 10E-2 MHzpsi. The packaged system shows negligible difference in frequency response between 25 and 400C. The fully packaged sensor passed standard benchtop acceptance tests and was evaluated on a flight-worthy engine.

  18. Drift velocity and pressure monitoring of the CMS muon drift chambers

    CERN Document Server

    Sonnenschein, Lars

    2011-01-01

    The drift velocity in drift tubes of the CMS muon chambers is a key parameter for the muon track reconstruction and trigger. It needs to be monitored precisely in order to detect any deviation from its nominal value. A change in absolute pressure, a variation of the gas admixture or a contamination of the chamber gas by air affect the drift velocity. Furthermore, the temperature and magnetic field influence its value. First data, taken with a dedicated Velocity Drift Chamber (VDC) built by RWTH Aachen IIIA are presented. Another important parameter to be monitored is the pressure inside the muon drift tube chambers. The differential pressure must not exceed a certain value and the absolute pressure has to be kept slightly above ambient pressure to prevent air from entering into the muon drift tube chambers in case of a leak. Latest drift velocity monitoring results are discussed.

  19. Electrostatic discharges and their effect on the validity of registered values in intracranial pressure monitors

    DEFF Research Database (Denmark)

    Andresen, Morten; Thomsen, Ole Cornelius; Juhler, Marianne

    2013-01-01

    , the authors have tried to determine if the ICP monitors from major manufacturers were affected by electrostatic discharges (ESDs), if the changes were permanent or transient in nature, and if the changes were modified by the addition of different electrical appliances normally used in the neurointensive care...... unit environment. Methods The authors established a test setup in the neurointensive care unit using a large container filled with isotonic saline, creating a phantom patient. Intracranial pressure monitors were sequentially lowered into the container and subjected to a predefined test battery of ESDs....... Results Five pressure monitors from 4 manufacturers were evaluated. Three monitors containing electrical circuitry at the tip of the transducer were all affected by ESDs. Clinically significant permanent changes in the reported ICP values for 1 pressure monitor were observed, as well as temporary...

  20. In Vitro and in vivo characterization of wireless and passive micro system enabling gastrointestinal pressure monitoring.

    Science.gov (United States)

    Shi, Qiang; Wang, Junbo; Chen, Deyong; Chen, Jian; Li, Jing; Bao, Kaikai

    2014-12-01

    This paper presents a wireless and passive micro pressure system based on the LC mutual inductance detection mechanism for gastrointestinal (GI) pressure monitoring. The micro pressure system is composed of a sensor capsule (a pressure sensitive micro capacitive sensor in series with an induction coil to form an LC tank) and a detection unit (a detection coil connected with a network analyzer). The pressure variations under measurement lead to changes in the capacitance of the pressure sensor and therefore a shift in the LC tank resonant frequency, quantified by the impedance measurement of the detection coil. The pressure sensor was fabricated using microfabrication processes with key parameters optimized. The in vitro characterization of the micro pressure system recorded a sensitivity of 0.2491 kHz/kPa (-10 kPa to 30 kPa). One-month rabbit stomach pressure monitoring was conducted based on the developed micro pressure system as a confirmation of device long term in vivo stability. Furthermore, rabbit stomach pressure variations before and after food feeding was recorded and compared where three distinctive contraction patterns (random contraction with low amplitude, irregular strong contractions and regular contraction in a cyclic manner) following food feeding were located. Compared to previous reported GI pressure sensors, this LC tank is featured with simple device structure without batteries and electrical components for energy transfer. Both in vitro and in vivo characterization confirm the functionality of the system, which may enable the gastrointestinal motility study in the near future.

  1. The DPSIR Framework and a Pressure-Oriented Water Quality Monitoring Approach to Ecological River Restoration

    Directory of Open Access Journals (Sweden)

    Björn Frostell

    2012-09-01

    Full Text Available Without monitoring anthropogenic pressures on the water environment, it is difficult to set realistic river restoration targets in relation to water quality. Therefore a more holistic approach is needed to systematically explore the links between socio-economic drivers and observed water quality-related impacts on river ecosystems. Using the DPSIR (Drivers-Pressures-State of the Environment-Impacts-Responses framework, this study linked ecological river restoration with the socio-economic sector, with the focus on promoting a pressure-oriented water quality monitoring system. Based on the European Water Framework Directive (WFD and relevant literature, it was found that most water quality-related indicators employed today are state/impacts-oriented, while very few are pressure-oriented. As a response, we call for more attention to a DPR (Drivers-Pressures-Responses framework in developing an industrial ecology-based pressure-oriented water quality monitoring system for aiding ecological river restoration planning. This approach is characterized in general by accounting for material-related flows throughout the socio-economic sector in relation to river ecosystem degradation. Then the obtained information would help decision makers take appropriate measures to alleviate various significant human-induced wastes and emissions at their sources. We believe that such a pressure-oriented monitoring system will substantially complement traditional state/impacts-oriented environmental and ecological monitoring and help develop more proactive planning and decision-making processes for specific river restoration projects and general water quality management.

  2. Patient Blood Pressure and Pulse Rate Monitoring With an Alert ...

    African Journals Online (AJOL)

    2012-12-01

    Dec 1, 2012 ... Blood pressure and pulse rate are two of the vital signs of humans and it is ... even from their homes and transfer the readings into the computer ... benefits from Omron's 'IntelliSense' .... (the port number assigned to the smart.

  3. Analys av ICP-pulsationer och CSF-dynamik : pulsationskurvan och effekter av ändrad kroppsposition, med implikationer för idiopatisk normaltryckshydrocefalus

    OpenAIRE

    2013-01-01

    The volume defined by the rigid cranium is shared by the brain, blood and cerebrospinal fluid (CSF). With every heartbeat the arterial blood volume briefly increases and venous blood and CSF are forced out of the cranium, leading to pulsatility in CSF flow and intracranial pressure (ICP). Altered CSF pulsatility has been linked to idiopathic normal pressure hydrocephalus (INPH), which involves enlarged cerebral ventricles and symptoms of gait/balance disturbance, cognitive decline and urinary...

  4. Fluid input control in burned patients with the aid of ultrasonic arterial blood pressure monitoring.

    Science.gov (United States)

    Banssillon, V; Latarjet, J

    1975-01-01

    Arterial blood pressure is nowadays easily and reliably measured with ultrasonic equipment. It correlates well with blood volume, and may therefore be used to guide fluid infusion in burned patients. Monitoring of blood pressure, instead of application of old-fashioned recipes, helps to avoid dangerous situations of hypovolemia or overload.

  5. Noninvasive Subharmonic Pressure Estimation for Monitoring Breast Cancer Response to Neoadjuvant Threapy

    Science.gov (United States)

    2009-09-01

    TITLE AND SUBTITLE Noninvasive Subharmonic Pressure Estimation for Monitoring Breast Cancer 5. FUNDING NUMBERS W81XWH-08-1-0503 6. AUTHOR(S...u sing subharmonic aided p ressure estimation (SHAPE ) to estimate the inte rstitial fluid pressure (IFP) in LABC. To date, in vitr o experiments

  6. Novel Approach for Ensuring Increased Validity in Home Blood Pressure Monitoring

    DEFF Research Database (Denmark)

    Wagner, Stefan Rahr; Toftegaard, Thomas Skjødeberg; Bertelsen, Olav Wedege

    This paper proposes a novel technique to increase the validity of home blood pressure monitoring by using various sensor technologies as part of an intelligent environment platform in the home of the user. A range of recommendations exists on how to obtain a valid blood pressure...

  7. Wireless system for monitoring Intra-abdominal pressure in patient with severe abdominal pathology

    Science.gov (United States)

    Sokolovskiy, S. S.; Shtotskiy, Y. V.; Leljanov, A. D.

    2017-01-01

    The paper discusses an experimental design of the wireless system for monitoring intra-abdominal pressure (IAP) using Bluetooth Low Energy technology. The possibility of measuring IAP via the bladder using a wireless pressure sensor with a hydrophobic bacteria filter between the liquid transmitting medium and the sensor element is grounded.

  8. Patient repositioning and pressure ulcer risk--monitoring interface pressures of at-risk patients.

    Science.gov (United States)

    Peterson, Matthew J; Gravenstein, Nikolaus; Schwab, Wilhelm K; van Oostrom, Johannes H; Caruso, Lawrence J

    2013-01-01

    Repositioning patients regularly to prevent pressure ulcers and reduce interface pressures is the standard of care, yet prior work has found that standard repositioning does not relieve all areas of at-risk tissue in nondisabled subjects. To determine whether this holds true for high-risk patients, we assessed the effectiveness of routine repositioning in relieving at-risk tissue of the perisacral area using interface pressure mapping. Bedridden patients at risk for pressure ulcer formation (n = 23, Braden score pressures recorded every 30 s while they received routine repositioning care for 4-6 h. All participants had specific skin areas (206 +/- 182 cm(2)) that exceeded elevated pressure thresholds for >95% of the observation period. Thirteen participants were observed in three distinct positions (supine, turned left, turned right), and all had specific skin areas (166 +/- 184 cm(2)) that exceeded pressure thresholds for >95% of the observation period. At-risk patients have skin areas that are likely always at risk throughout their hospital stay despite repositioning. Healthcare providers are unaware of the actual tissue-relieving effectiveness (or lack thereof) of their repositioning interventions, which may partially explain why pressure ulcer mitigation strategies are not always successful. Relieving at-risk tissue is a necessary part of pressure ulcer prevention, but the repositioning practice itself needs improvement.

  9. Intracranial Pressure Monitoring as a Part of Multimodal Monitoring Management of Patients with Critical Polytrauma: Correlation between Optimised Intensive Therapy According to Intracranial Pressure Parameters and Clinical Picture

    Science.gov (United States)

    Luca, Loredana; Rogobete, Alexandru Florin; Bedreag, Ovidiu Horea; Sarandan, Mirela; Cradigati, Carmen Alina; Papurica, Marius; Gruneantu, Anelore; Patrut, Raluca; Vernic, Corina; Dumbuleu, Corina Maria; Sandesc, Dorel

    2015-01-01

    Objective Trauma patient requires a complex therapeutic management because of multiple severe injuries or secondary complications. The most significant injury found in patients with trauma is head injury, which has the greatest impact on mortality. Intracranial pressure (ICP) monitoring is required in severe traumatic head injury because it optimises treatment based on ICP values and cerebral perfusion pressure (CPP). Methods From a total of 64 patients admitted in the intensive care unit (ICU) ‘Casa Austria’, from the Polytraumatology Clinic of the Emergency County Hospital “Pius Brinzeu” Timisoara, Romania, between January 2014 and December 2014; only patients who underwent ICP monitoring (n=10) were analysed. The study population was divided into several categories depending on the time passed since trauma to the time of installation of ICP monitoring (24 h). Comparisons were made in terms of the number of days admitted in the ICU and mortality between patients with head injury who benefited and those who did not benefit from ICP monitoring. Results The results show the positive influence of ICP monitoring on the number of admission days in ICU because of the possibility that the number of admission days to augment therapeutic effects in patients who benefited from ICP monitoring reduces by 1.93 days compared with those who did not undergo ICP monitoring. Conclusion ICP monitoring and optimizing therapy according to the ICP and CPP has significant influence on the rate of survival. ICP monitoring is necessary in all patients with head trauma injury according to recent guidelines. The main therapeutic goal in the management of the trauma patient with head injury is to minimize the destructive effects of the associated side effects. PMID:27366538

  10. Transpulmonary pressure monitoring during mechanical ventilation: a bench-to-bedside review.

    Science.gov (United States)

    Mietto, Cristina; Malbrain, Manu L N G; Chiumello, Davide

    2015-01-01

    Different ventilation strategies have been suggested in the past in patients with acute respiratory distress syndrome (ARDS). Airway pressure monitoring alone is inadequate to assure optimal ventilatory support in ARDS patients. The assessment of transpulmonary pressure (PTP) can help clinicians to tailor mechanical ventilation to the individual patient needs. Transpulmonary pressure monitoring, defined as airway pressure (Paw) minus intrathoracic pressure (ITP), provides essential information about chest wall mechanics and its effects on the respiratory system and lung mechanics. The positioning of an esophageal catheter is required to measure the esophageal pressure (Peso), which is clinically used as a surrogate for ITP or pleural pressure (Ppl), and calculates the transpulmonary pressure. The benefits of such a ventilation approach are avoiding excessive lung stress and individualizing the positive end-expiratory pressure (PEEP) setting. The aim is to prevent over-distention of alveoli and the cyclic recruitment/derecruitment or shear stress of lung parenchyma, mechanisms associated with ventilator-induced lung injury (VILI). Knowledge of the real lung distending pressure, i.e. the transpulmonary pressure, has shown to be useful in both controlled and assisted mechanical ventilation. In the latter ventilator modes, Peso measurement allows one to assess a patient's respiratory effort, patient-ventilator asynchrony, intrinsic PEEP and the calculation of work of breathing. Conditions that have an impact on Peso, such as abdominal hypertension, will also be discussed briefly.

  11. Mini invasive hemodynamic monitoring: from arterial pressure to cardiac output

    OpenAIRE

    Della Rocca, Giorgio; Cecconi, Maurizio; Costa, Maria Gabriella

    2008-01-01

    To evaluate the Cardiac Output (CO) the standard invasive pulmonary artery catheter (PAC) is considered today the gold standard. The major criticism to the PAC is that its level of invasiveness is not supported by an improvement in patient's outcome. The interest to lesser and lesser invasive techniques is high. Therefore, the alternative techniques have been recently developed.Cardiac Output can be monitored continuously by different devices that analyze the arterial waveform to track change...

  12. A novel method for long-term monitoring of intracranial pressure in rats

    DEFF Research Database (Denmark)

    Uldall, Maria Schmidt; Juhler, Marianne; Skjolding, Anders Daehli;

    2014-01-01

    BACKGROUND: In preclinical neurological studies, monitoring intracranial pressure (ICP) in animal models especially in rodents is challenging. Further, the lack of methods for long-term ICP monitoring has limited the possibilities to conduct prolonged studies on ICP fluctuations in parallel...... and in the epidural space. The two pressures were recorded twice a week for 59 days and the correlation was studied. RESULTS: The two pressure recordings correlated exceptionally well and the R(2) values on each recording day ranged between 0.99 and 1.00. However, the ventricular probes caused a number...

  13. Development and investigation of MOEMS type displacement-pressure sensor for biological information monitoring

    Science.gov (United States)

    Ostasevicius, Vytautas; Malinauskas, Karolis; Janusas, Giedrius; Palevicius, Arvydas; Cekas, Elingas

    2016-04-01

    The aim of this paper is to develop and investigate MOEMS displacement-pressure sensor for biological information monitoring. Developing computational periodical microstructure models using COMSOL Multiphysics modeling software for modal and shape analysis and implementation of these results for design MOEMS displacement-pressure sensor for biological information monitoring was performed. The micro manufacturing technology of periodical microstructure having good diffraction efficiency was proposed. Experimental setup for characterisation of optical properties of periodical microstructure used for design of displacement-pressure sensor was created. Pulsating human artery dynamic characteristics in this paper were analysed.

  14. Crystallization of M-CSF.alpha.

    Science.gov (United States)

    Pandit, Jayvardhan; Jancarik, Jarmila; Kim, Sung-Hou; Koths, Kirston; Halenbeck, Robert; Fear, Anna Lisa; Taylor, Eric; Yamamoto, Ralph; Bohm, Andrew

    1999-01-01

    The present invention is directed to methods for crystallizing macrophage colony stimulating factor (M-CSF) and to a crystalline M-CSF produced thereby. The present invention is also directed to methods for designing and producing M-CSF agonists and antagonists using information derived from the crystallographic structure of M-CSF. The invention is also directed to methods for screening M-CSF agonists and antagonists. In addition, the present invention is directed to an isolated, purified, soluble and functional M-CSF receptor.

  15. 24-hour ambulatory blood pressure monitoring in children with familial dysautonomia.

    Science.gov (United States)

    Nussinovitch, Naomi; Nussinovitch, Moshe; Peleg, Edna; Rosenthal, Talma

    2005-04-01

    Familial dysautonomia (Riley Day syndrome) is a genetic disease. The present study of 24-hour ambulatory blood pressure monitoring in children with familial dysautonomia was carried out to investigate the pattern of blood pressure in this syndrome. To the best of our knowledge, this is the only description of patients with 24-hour blood pressure monitoring. Vasomotor instability reflected in extreme hypertension and hypotension was recorded by 24-hour ambulatory blood pressure monitoring in three patients with familial dysautonomia: a 16-year old girl, a 14-year old boy and a 3-year old boy. Recordings were taken on a routine school day in the first two patients and during hospitalization in the third. Patients 1 and 2 displayed circadian rhythm but with significantly higher than normal blood pressure and heart rate. Patient 3 exhibited these fluctuations to a lesser degree. Postural hypotension without compensatory tachycardia was frequently seen in all three patients. Unusual variability in blood pressure was recorded during routine activities in patients 1 and 2 and during an acute attack in patient 3. Close monitoring of antihypertensive therapy should be considered in familial dysautonomia patients in whom blood pressure reaches excessive levels.

  16. Tactile shoe inlays for high speed pressure monitoring

    DEFF Research Database (Denmark)

    Drimus, Alin; Mátéfi-Tempfli, Stefan

    2015-01-01

    pressure sensitive cells and the use of high speed electronics and multiplexing algorithms provides frame rates of 100 Hz. The sensors tolerate overloads while showing a consistent output. The developed prototypes show a high potential not only for robotics, but also for use in sensorised human prosthetics.......This work describes the development of flexible tactile sensor shoe inlays for humanoid robots. Their design is based on a sandwich structure of flexible layers with a thin sheet of piezoresistive rubber as main transducer element. The layout and patterning of top and bottom electrodes give 1024...

  17. Continuous blood pressure monitoring in cirrhosis. Relations to splanchnic and systemic haemodynamics

    DEFF Research Database (Denmark)

    Møller, S; Christensen, E; Henriksen, Jens Henrik Sahl

    1997-01-01

    post-sinusoidal resistance, a low plasma volume, a short central circulation time, and the presence of ascites. In contrast, a low intra-arterial blood pressure was determined by a low serum sodium, a low haemoglobin, and a high cardiac output. Diuretic treatment did not influence this model......BACKGROUND/AIMS: Low arterial blood pressure is recognised as a distinctive factor in the hyperdynamic circulation in cirrhosis. 24-hour monitoring of the blood pressure and heart rate has recently revealed a reduced circadian variation with relation to liver function. However, associations...... with cirrhosis than in matched controls (p low 24-h arterial blood pressure were a high...

  18. Severe head injuries and intracranial pressure monitoring outcome in Southern Iran

    Directory of Open Access Journals (Sweden)

    Majid Reza Farrokhi

    2006-11-01

    Full Text Available BACKGROUND: Head injury is still a major cause of death and disability. Despite advances in intensive monitoring and clinical practice, little data is available to show the predictive value of intracranial pressure monitoring in assessment of the outcome of head injuries. This study was undertaken to evaluate this predictive value and is the first Iranian study in which ICP monitoring has been included. METHODS: In a prospective study from September 1999 to September 2003, all head- injured patients (53 patients with GCS of 4-8 who were admitted to Nemazee Hospital of Shiraz University of Medical Sciences were included in this study. Subarachnoid screw method or ventricular catheter via ventriculostomy was used to determine intracranial pressure. Patients were monitored for 3 days and were followed for two years at 6-month intervals. RESULTS: Car accidents were the most common cause of head injury (43.3% and 43.3% of patients had GCS of 8. Sixty percent of patients had abnormal intracranial pressure. The patients were most commonly in their first decade of life (18.8% and 81% of patients were male. Controlling increased intracranial pressure was successful in 60% of patients and resulted in a decrease of mortality rate from 60% to 15%. CONCLUSIONS: Early treatment of increased intracranial pressure in head injury patients would be beneficial in reducing mortality and morbidity rates. KEY WORDS: Southern Iran, head injury, outcome, intracranial pressure.

  19. Intracerebral abscess associated with the Camino intracranial pressure monitor: case report and review of the literature.

    Science.gov (United States)

    Morton, Ryan; Lucas, Timothy H; Ko, Andrew; Browd, Samuel R; Ellenbogen, Richard G; Chesnut, R M

    2012-07-01

    Intracranial pressure (ICP) monitoring is a mainstay in the management of traumatic brain injury. Large investigations have validated the safety and efficacy of ICP monitors in comatose patients. Clinically relevant infections are extremely rare and cerebral abscess has never been reported with the Camino device. We describe an exceptional case of a life-threatening intracerebral abscess from an intraparenchymal ICP monitor. A 35-month-old child required 7 days of ICP monitoring after a fall from a 2-story window. His hospital course was complicated by severe airway edema treated, in part, with high-dose corticosteroid therapy for a total of 10 days. Two weeks later, the patient deteriorated acutely owing to a large intracerebral abscess under the previous ICP monitor site. Urgent craniotomy with evacuation of the abscess was performed on 2 separate occasions. Cultures grew methicillin-sensitive Staphylococcus aureus, which was treated with long-term antibiotics. At the 3-month follow-up, the patient was meeting age-appropriate milestones without focal deficits. To the best of our knowledge, this is the first report describing an intracerebral abscess as a complication from an intraparenchymal pressure monitor. Corticosteroid therapy may have constituted an independent risk factor for the ICP monitor--associated infection, as well as reinsertion of the ICP monitoring device at the same site. That this is the first reported parenchymal infectious complication underscores the safety of this device with respect to infection. When reinsertion of a parenchymal monitor is considered, a new site should be chosen.

  20. Arterial pressure changes monitoring with a new precordial noninvasive sensor

    Directory of Open Access Journals (Sweden)

    Faita Francesco

    2008-08-01

    Full Text Available Abstract Background Recently, a cutaneous force-frequency relation recording system based on first heart sound amplitude vibrations has been validated. A further application is the assessment of Second Heart Sound (S2 amplitude variations at increasing heart rates. The aim of this study was to assess the relationship between second heart sound amplitude variations at increasing heart rates and hemodynamic changes. Methods The transcutaneous force sensor was positioned in the precordial region in 146 consecutive patients referred for exercise (n = 99, dipyridamole (n = 41, or pacing stress (n = 6. The curve of S2 peak amplitude variation as a function of heart rate was computed as the increment with respect to the resting value. Results A consistent S2 signal was obtained in all patients. Baseline S2 was 7.2 ± 3.3 mg, increasing to 12.7 ± 7.7 mg at peak stress. S2 percentage increase was + 133 ± 104% in the 99 exercise, + 2 ± 22% in the 41 dipyridamole, and + 31 ± 27% in the 6 pacing patients (p Conclusion S2 recording quantitatively documents systemic pressure changes.

  1. Effects of inner materials on the sensitivity and phase depth of wireless inductive pressure sensors for monitoring intraocular pressure

    Science.gov (United States)

    Jang, Cheol-In; Shin, Kyeong-Sik; Kim, Mi Jeung; Yun, Kwang-Seok; Park, Ki Ho; Kang, Ji Yoon; Lee, Soo Hyun

    2016-03-01

    In this research, we developed wireless, inductive, pressure sensors with high sensitivity and investigated the effects of the inner materials (copper or ferrite) on the performance of the sensors. The proposed sensor is comprised of two parts, i.e., the top and the bottom parts. The top part includes a micro coil and a capacitor for the wireless transfer of data, and the bottom part includes the inner materials and a thick or thin flexible membrane to induce changes in the inductance. An anchor is used to assemble the top and bottom parts. The behavior of the sensor with copper was based on the eddy current effect, and, as the pressure increased, its resonance frequency increased, while its phase depth decreased exponentially. The principle of the sensor with ferrite was related to the effective permeability between a ferrite and a coil, and its response was the opposite of that with copper, i.e., as the pressure increased, the resonance frequency decreased linearly, and the phase depth increased linearly. These different operational mechanisms can be explained by the changes in the equations of inductance presented in this paper. After characterizing four different types of inductive pressure sensors in ambient air, one type of inductive pressure sensor was used to monitor the intraocular pressure (IOP) of a rabbit's eye as a biomedical application. The results showed that, in the animal tests, the measured responsivity and sensitivity were 16.7 kHz/mmHg and 1340 ppm/mmHg, respectively. These data indicate that the proposed sensor is a good candidate for monitoring IOP.

  2. Monitoring of low pressure plasma systems; Ueberwachung von Niederdruck-Plasmaanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Michaeli, W.; Hegenbart, A.; Binkowski, D.; Fragstein, F. v. [Inst. fuer Kunststoffverarbeitung (IKV) an der RWTH Aachen (Germany)

    2007-02-15

    The optical emission spectroscopy (OES) is a very flexible and easy to use method to monitor industrial plasma processes. By directly monitoring the plasma itself many additional factors influencing low pressure plasma processes can be observed. First of all factors that can not be controlled directly play an important role in this context. Examples are contaminations and leaks in the plasma system. These can negatively influence the reproducibility of production processes. In this paper the effect of a leak on the coating and the plasma process is being shown. Additionally the detection of contaminations and sealing problems in a microwave plasma source is being demonstrated. By using the correlations being presented the OES can be used to continually monitor low pressure plasma systems and thus enhance reproducibility of industrial low pressure plasma processes. (orig.)

  3. Pressure monitoring inside Meckel's cave during percutaneous microcompression of gasserian ganglion.

    Science.gov (United States)

    Zanusso, M; Curri, D; Landi, A; Colombo, F; Volpin, L; Cervellini, P

    1991-01-01

    During percutaneous microcompression of the gasserian ganglion for the relief of trigeminal neuralgia, a computerized technique for monitoring the pressure inside Meckel's cave was employed in 22 patients. A dedicated transducer connected to a computer records the balloon inflation pressure. Its variations are discernible within tenths of a bar and are plotted in relation to time. The intraoperative pressure inside Meckel's cave is from 0.9 to 2.4 bars. When pressure was low, there was recurrence of pain. The highest values of pressure (1.9-2.4 bars) were observed in most of the patients suffering from untoward side effects. The clinical results seem to be influenced by the level of the intraoperative intracavitary pressure.

  4. The estimated sensitivity and specificity of compartment pressure monitoring for acute compartment syndrome.

    Science.gov (United States)

    McQueen, Margaret M; Duckworth, Andrew D; Aitken, Stuart A; Court-Brown, Charles M

    2013-04-17

    The aim of our study was to document the estimated sensitivity and specificity of continuous intracompartmental pressure monitoring for the diagnosis of acute compartment syndrome. From our prospective trauma database, we identified all patients who had sustained a tibial diaphyseal fracture over a ten-year period. A retrospective analysis of 1184 patients was performed to record and analyze the documented use of continuous intracompartmental pressure monitoring and the use of fasciotomy. A diagnosis of acute compartment syndrome was made if there was escape of muscles at fasciotomy and/or color change in the muscles or muscle necrosis intraoperatively. A diagnosis of acute compartment syndrome was considered incorrect if it was possible to close the fasciotomy wounds primarily at forty-eight hours. The absence of acute compartment syndrome was confirmed by the absence of neurological abnormality or contracture at the time of the latest follow-up. Of 979 monitored patients identified, 850 fit the inclusion criteria with a mean age of thirty-eight years (range, twelve to ninety-four years), and 598 (70.4%) were male (p compartment syndrome: 141 had acute compartment syndrome (true positives), six did not have it (false positives), and five underwent fasciotomy despite having a normal differential pressure reading, with subsequent operative findings consistent with acute compartment syndrome (false negatives). Of the 698 patients (82.1%) who did not undergo fasciotomy, 689 had no evidence of any late sequelae of acute compartment syndrome (true negatives) at a mean follow-up time of fifty-nine weeks. The estimated sensitivity of intracompartmental pressure monitoring for suspected acute compartment syndrome was 94%, with an estimated specificity of 98%, an estimated positive predictive value of 93%, and an estimated negative predictive value of 99%. The estimated sensitivity and specificity of continuous intracompartmental pressure monitoring for the diagnosis of

  5. Novel Approach for Ensuring Increased Validity in Home Blood Pressure Monitoring

    DEFF Research Database (Denmark)

    Wagner, Stefan Rahr; Toftegaard, Thomas Skjødeberg; Bertelsen, Olav Wedege

    This paper proposes a novel technique to increase the validity of home blood pressure monitoring by using various sensor technologies as part of an intelligent environment platform in the home of the user. A range of recommendations exists on how to obtain a valid blood pressure but with the devi......This paper proposes a novel technique to increase the validity of home blood pressure monitoring by using various sensor technologies as part of an intelligent environment platform in the home of the user. A range of recommendations exists on how to obtain a valid blood pressure...... but with the devices currently available it cannot be verified whether a user is actually following the recommendations or not. An initial prototype is presented implementing part of the proposed solution including a limited pilot study as a status on the work in progress. Results indicate that the solution...

  6. Carotid arterial blood pressure waveform monitoring using a portable ultrasound system.

    Science.gov (United States)

    Joohyun Seo; Pietrangelo, Sabino J; Hae-Seung Lee; Sodini, Charles G

    2015-08-01

    This work presents a non-invasive arterial blood pressure (ABP) waveform monitoring technique using ultrasound. A portable ultrasound system to excite ultrasound transducers and acquire data is designed with off-the-shelf components. The insonation angles are identified using a vector Doppler technique based on the cosine dependency of the Doppler signals. The pulse pressure of an estimated waveform at the left common carotid artery is compared to the standard sphygmomanometer measurement in a clinical test. The estimated carotid ABP waveform shows excellent agreement to the finger ABP waveform with expected discrepancy of the systolic peak shape due to different measurement sites. The proposed method also tracks slow blood pressure fluctuations. This validation on human subjects shows potential for a noninvasive blood pressure waveform monitoring device at central arterial sites.

  7. Development of a Calibration and Monitoring System for GD-1 High Pressure Common Rail Diesel Engine

    Institute of Scientific and Technical Information of China (English)

    王俊席; 杨林; 冯静; 冒晓建; 卓斌

    2004-01-01

    Based on CAN calibration protocol, a new calibration and monitoring system was developed for the GD1 high pressure common rail diesel engine. CAN driver block, monitoring program and calibration program for this system were designed respectively. The inquiry mode was used in the monitoring program and the interrupt mode was used in calibration program. The calibration program was designed in structural programming model. This system provides a reliable, accurate and quick CAN bus between ECU and PC, with baud rate up to 500Kbit/s.The implementation of the compatible and universal CAN calibration protocol makes it easy to displace the system and its function modules. It also provides friendly, compatible and flexible calibration interface, and the functions of online calibration and real-time monitoring. This system was successfully used in a GD-1 high pressure common rail diesel engine and the engine performance and exhaust emissions were significantly improved.

  8. [Realization of a compact mobile phone based wireless plantar pressure monitoring system and application].

    Science.gov (United States)

    Liu, Lin; Liu, Jing

    2012-05-01

    An improved compact mobile phone based wireless plantar pressure monitoring system and software are proposed based on former progress, which can collect pressure data by sensors and circuit board, transmit data through Bluetooth wirelessly, and display and calculate the data on the mobile terminal. Conceptual experiments carried out demonstrate the feasibility and accuracy of the new system The system is expected to be widely used in the future owing to its portability, ease of use, and cost-effectiveness

  9. An Improved Flexible Telemetry System to Autonomously Monitor Sub-Bandage Pressure and Wound Moisture

    OpenAIRE

    Nasir Mehmood; Alex Hariz; Sue Templeton; Voelcker, Nicolas H.

    2014-01-01

    This paper presents the development of an improved mobile-based telemetric dual mode sensing system to monitor pressure and moisture levels in compression bandages and dressings used for chronic wound management. The system is fabricated on a 0.2 mm thick flexible printed circuit material, and is capable of sensing pressure and moisture at two locations simultaneously within a compression bandage and wound dressing. The sensors are calibrated to sense both parameters accurately, and the data ...

  10. Research on simulation and experiment of noninvasive intracranial pressure monitoring based on acoustoelasticity effects

    OpenAIRE

    Wu J.; He W; Chen W; Zhu L

    2013-01-01

    Jun Wu1, Wei He2, Wei-min Chen1, Lian Zhu21Key Laboratory of Optoelectronic Technology and Systems, 2State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University, Chongqing, People’s Republic of ChinaAbstract: The real-time monitoring of intracranial pressure (ICP) is very important for craniocerebrally critically ill patients, but it is very difficult to realize long-time monitoring for the traditional invasive method, which very...

  11. Ambulatory blood pressure monitoring of patients with heart failure: a new prognosis marker

    Directory of Open Access Journals (Sweden)

    Manoel F. Canesin

    2002-01-01

    Full Text Available OBJECTIVE: To evaluate the relationship between 24-hour ambulatory arterial blood pressure monitoring and the prognosis of patients with advanced congestive heart failure. METHODS: We studied 38 patients with NYHA functional class IV congestive heart failure, and analyzed left ventricular ejection fraction, diastolic diameter, and ambulatory blood pressure monitoring data. RESULTS: Twelve deaths occurred. Left ventricular ejection fraction (35.2±7.3% and diastolic diameter (72.2±7.8mm were not correlated with the survival. The mean 24-hour (SBP24, waking (SBPw, and sleeping (SBPs systolic pressures of the living patients were higher than those of the deceased patients and were significant for predicting survival. Patients with mean SBP24, SBPv, and SBPs > or = 105mmHg had longer survival (p=0.002, p=0.01 and p=0.0007, respectively. Patients with diastolic blood pressure sleep decrements (dip and patients with mean blood pressure dip or = 105 mmHg CONCLUSION: Ambulatory blood pressure monitoring appears to be a useful method for evaluating patients with congestive heart failure.

  12. Ischemic cardiac complications following G-CSF.

    Science.gov (United States)

    Eckman, Peter M; Bertog, Stefan C; Wilson, Robert F; Henry, Timothy D

    2010-07-01

    Granulocyte-colony stimulating factor (G-CSF) is commonly used in bone marrow transplant donors to increase the number of circulating progenitor cells. G-CSF has also been studied following myocardial infarction, but concern has been raised about the risks of G-CSF administration in patients with coronary artery disease. We present two cases of ischemic cardiac complications that are likely to be related to administration of G-CSF and provide a contemporary overview of the literature on the cardiovascular risks of G-CSF.

  13. Ambulatory Blood Pressure Monitoring: Five Decades of More Light and Less Shadows

    Science.gov (United States)

    Nobre, Fernando; Mion Junior, Décio

    2016-01-01

    Casual blood pressure measurements have been extensively questioned over the last five decades. A significant percentage of patients have different blood pressure readings when examined in the office or outside it. For this reason, a change in the paradigm of the best manner to assess blood pressure has been observed. The method that has been most widely used is the Ambulatory Blood Pressure Monitoring - ABPM. The method allows recording blood pressure measures in 24 hours and evaluating various parameters such as mean BP, pressure loads, areas under the curve, variations between daytime and nighttime, pulse pressure variability etc. Blood pressure measurements obtained by ABPM are better correlated, for example, with the risks of hypertension. The main indications for ABPM are: suspected white coat hypertension and masked hypertension, evaluation of the efficacy of the antihypertensive therapy in 24 hours, and evaluation of symptoms. There is increasing evidence that the use of ABPM has contributed to the assessment of blood pressure behaviors, establishment of diagnoses, prognosis and the efficacy of antihypertensive therapy. There is no doubt that the study of 24-hour blood pressure behavior and its variations by ABPM has brought more light and less darkness to the field, which justifies the title of this review. PMID:27168473

  14. [Mobile phone platform for wireless monitoring of human dynamic plantar pressure].

    Science.gov (United States)

    Wang, Hao; Han, Meng; Liu, Jing

    2010-11-01

    This paper constructed a plantar pressure sensing system based on Bluetooth communication of mobile phone with embedded Windows Mobile system. With the MCU (Microprocessor Control Unit) and Bluetooth module, the pressure sensor and the data acquisition circuit was designed and integrated, with software developed under Visual Studio 2008 environment. The real-time monitoring of human dynamic plantar pressure signal, and transferring, displaying and storing the recorded data on a mobile phone were achieved. This method offers an important measure to acquire human gait information via a pervasive and low cost way.

  15. Ceramic MEMS Designed for Wireless Pressure Monitoring in the Industrial Environment

    Directory of Open Access Journals (Sweden)

    Marko Pavlin

    2011-12-01

    Full Text Available This paper presents the design of a wireless pressure-monitoring system for harsh-environment applications. Two types of ceramic pressure sensors made with a low-temperature cofired ceramic (LTCC were considered. The first type is a piezoresistive strain gauge pressure sensor. The second type is a capacitive pressure sensor, which is based on changes of the capacitance values between two electrodes: one electrode is fixed and the other is movable under an applied pressure. The design was primarily focused on low power consumption. Reliable operation in the presence of disturbances, like electromagnetic interference, parasitic capacitances, etc., proved to be contradictory constraints. A piezoresistive ceramic pressure sensor with a high bridge impedance was chosen for use in a wireless pressure-monitoring system and an acceptable solution using energy-harvesting techniques has been achieved. The described solution allows for the integration of a sensor element with an energy harvester that has a printed thick-film battery and complete electronics in a single substrate packaged inside a compact housing.

  16. Summary of Activities for Health Monitoring of Composite Overwrapped Pressure Vessels

    Science.gov (United States)

    Russell, Rick; Skow, Miles

    2013-01-01

    This three-year project (FY12-14) will design and demonstrate the ability of new Magnetic Stress Gages for the measurement of stresses on the inner diameter of a Composite Overwrapped Pressure Vessel overwrap. The sensors are being tested at White Sands Testing Facility (WSTF) where the results will be correlated with a known nondestructive technique acoustic emission. The gages will be produced utilizing Meandering Winding Magnetometer (MWM) and/or MWM array eddy current technology. The ultimate goal is to utilize this technology for the health monitoring of Composite Overwrapped Pressure Vessels for all future flight programs. The first full-scale pressurization test was performed at WSTF in June 2012. The goals of this test were to determine adaptations of the magnetic stress gauge instrumentation that would be necessary to allow multiple sensors to monitor the vessel's condition simultaneously and to determine how the sensor response changes with sensor selection and orientation. The second full scale pressurization test was performed at WSTF in August 2012. The goals of this test were to monitor the vessel's condition with multiple sensors simultaneously, to determine the viability of the multiplexing units (MUX) for the application, and to determine if the sensor responses in different orientations are repeatable. For both sets of tests the vessel was pressured up to 6,000 psi to simulate maximum operating pressure. Acoustic events were observed during the first pressurization cycle. This suggested that the extended storage period prior to use of this bottle led to a relaxation of the residual stresses imparted during auto-frettage. The pressurization tests successfully demonstrated the use of multiplexers with multiple MWM arrays to monitor a vessel. It was discovered that depending upon the sensor orientation, the frequencies, and the sense element, the MWM arrays can provide a variety of complementary information about the composite overwrapped pressure

  17. Improvement of a sensor unit for wrist blood pressure monitoring system

    Science.gov (United States)

    Koo, Sangjun; Kwon, Jongwon; Park, Yongman; Ayuzenara, Odgerel; Kim, Hiesik

    2007-12-01

    A blood pressure sensor unit for ubiquitous healthcare monitoring was newly developed. The digital wrist band-type blood pressure devices for home are popular already in the market. It is useful for checking blood pressure level at home and control of hypertension. Especially, it is very essential home device to check the health condition of blood circulation disease. Nowadays many product types are available. But the measurement of blood pressure is not accurate enough compared with the mechanical type. It needs to be upgraded to assure the precise health data enough to use in the hospital. The structure, feature and output signal of capacitor type pressure sensors are analyzed. An improved design of capacitor sensor is suggested. It shows more precise health data after use on a wrist band type health unit. They can be applied for remote u-health medical service.

  18. Continuous blood pressure monitoring in cirrhosis. Relations to splanchnic and systemic haemodynamics

    DEFF Research Database (Denmark)

    Møller, Søren; Christensen, E; Henriksen, Jens Henrik

    1997-01-01

    with cirrhosis than in matched controls (p blood pressures and heart rate, pertinent variables were included in a multivariate regression model. This model revealed that independent determinants of a low 24-h arterial blood pressure were a high...... post-sinusoidal resistance, a low plasma volume, a short central circulation time, and the presence of ascites. In contrast, a low intra-arterial blood pressure was determined by a low serum sodium, a low haemoglobin, and a high cardiac output. Diuretic treatment did not influence this model......BACKGROUND/AIMS: Low arterial blood pressure is recognised as a distinctive factor in the hyperdynamic circulation in cirrhosis. 24-hour monitoring of the blood pressure and heart rate has recently revealed a reduced circadian variation with relation to liver function. However, associations...

  19. Agreement Between Doppler and Invasive Blood Pressure Monitoring in Anesthetized Dogs Weighing <5 kg.

    Science.gov (United States)

    Kennedy, Martin J; Barletta, Michele

    2015-01-01

    The objectives of this study were to determine if Doppler (DOP) blood pressure measurements more closely estimate either invasive systolic or invasive mean arterial blood pressures (ISAP or IMAP, respectively) in small dogs under general anesthesia and to assess the ability of DOP to detect anesthesia-related hypotension in small dogs. Blood pressure measurements (n = 203) were obtained from 10 client-owned dogs. DOP, ISAP, and IMAP were recorded simultaneously, and the data were categorized into two groups: hypotensive (ISAP dogs, suggesting that DOP measures systolic arterial blood pressure in dogs dogs with hypotension, DOP met all of the performance criteria for noninvasive blood pressure monitors recommended by the American College of Veterinary Internal Medicine. DOP is an acceptably accurate and highly specific means of detecting hypotension in small dogs under general anesthesia.

  20. Utility of the theory of planned behavior to predict nursing staff blood pressure monitoring behaviours.

    Science.gov (United States)

    Nelson, Joan M; Cook, Paul F; Ingram, Jennifer C

    2014-02-01

    To evaluate constructs from the theory of planned behavior (TPB, Ajzen 2002) - attitudes, sense of control, subjective norms and intentions - as predictors of accuracy in blood pressure monitoring. Despite numerous initiatives aimed at teaching blood pressure measurement techniques, many healthcare providers measure blood pressures incorrectly. Descriptive, cohort design. Medical assistants and licensed practical nurses were asked to complete a questionnaire on TPB variables. These nursing staff's patients had their blood pressures measured and completed a survey about techniques used to measure their blood pressure. We correlated nursing staff's responses on the TBP questionnaire with their intention to measure an accurate blood pressure and with the difference between their actual blood pressure measurement and a second measurement taken by a researcher immediately after the clinic visit. Patients' perceptions of MAs' and LPNs' blood pressure measurement techniques were examined descriptively. Perceived control and social norm predicted intention to measure an accurate blood pressure, with a negative relationship between knowledge and intention. Consistent with the TPB, intention was the only significant predictor of blood pressure measurement accuracy. Theory of planned behavior constructs predicted the healthcare providers' intention to measure blood pressure accurately and intention predicted the actual accuracy of systolic blood pressure measurement. However, participants' knowledge about blood pressure measurement had an unexpected negative relationship with their intentions. These findings have important implications for nursing education departments and organisations which traditionally invest significant time and effort in annual competency training focused on knowledge enhancement by staff. This study suggests that a better strategy might involve efforts to enhance providers' intention to change, particularly by changing social norms or increasing

  1. Comparison of femoral and auricular arterial blood pressure monitoring in pigs.

    Science.gov (United States)

    Bass, Louise M E; Yu, Dao-Yi; Cullen, Len K

    2009-09-01

    To compare arterial blood pressure measurements obtained from the femoral and auricular arteries in anaesthetized pigs. Prospective experimental study. Fifteen female Large White pigs were used weighing 21.3 +/- 2.3 kg. The pigs were anaesthetized with tiletamine/zolazepam and xylazine administered intramuscularly, and anaesthesia maintained with isoflurane delivered in oxygen/nitrogen. Arterial oxygen partial pressures were maintained between 11.3 and 13.3 kPa and PaCO(2) between 4.6 and 6.0 kPa. Monitoring included electrocardiogram, capnography and invasive blood pressure. The auricular and femoral arteries were catheterized for continuous systolic (SAP), diastolic (DAP) and mean arterial pressure (MAP) measurements. Measurements were recorded every 15 minutes. Statistical analysis involved a Bland-Altman plot analysis. The mean difference +/- confidence intervals between the femoral and the auricular arterial diastolic, systolic and mean blood pressure measurements during hypotension were 2 +/- 7, 2 +/- 5 and 2 +/- 5 mmHg respectively. In conditions of normotension mean difference +/- confidence intervals, of femoral and auricular arterial blood pressure measurements of diastolic, systolic and mean blood pressure were 4 +/- 5, 3 +/- 7 and 4 +/- 4 mmHg respectively. In conditions of increased arterial blood pressure, mean difference +/- confidence intervals, of femoral and auricular arterial blood pressure measurements of diastolic, systolic and mean blood pressure were 4 +/- 5, 3 +/- 8 and 4 +/- 4 mmHg respectively. Auricular artery catheterization is easier and quicker to perform. Pressure measurements from the auricular artery compared well with the femoral artery. We found that auricular arterial blood pressures were similar to femoral arterial values under the conditions of this experiment. We did not test extremes of blood pressure or significant alterations in body temperature.

  2. Validation of a two-axis accelerometer for monitoring patient activity during blood pressure or ECG holter monitoring.

    Science.gov (United States)

    Wetzler, Marie-Laure; Borderies, Jean René; Bigaignon, Odile; Guillo, Pascal; Gosse, Philippe

    2003-12-01

    The aim of the study was to evaluate the efficiency of a position/activity monitoring system based on a dual-axis accelerometer strapped to the subject's thigh and a position sensor located within a monitor placed on the subject's belt. Twenty-six subjects wearing two monitors (one accelerometer on each thigh) were submitted to various activities and positions under the control of an observer. An analysis of each tracing was performed both manually by a technician and automatically by dedicated software before being compared with the information gathered during the study. The accelerometer allowed accurate discrimination between the standing versus the sitting and lying positions. The sitting and lying positions were correctly detected by the built-in position sensor provided the unit was firmly attached. Walking was adequately detected by the accelerometer. The activity score was well correlated with treadmill speed. Changes in position and activity were detected with a mean error of less than 3 s. The combination of an accelerometer placed on the subject's thigh and a position sensor located at the subject's waist appeared to be a suitable system for position/activity monitoring during ambulatory ECG and blood pressure monitoring.

  3. Clinical characteristics of resistant hypertension evaluated by ambulatory blood pressure monitoring.

    Science.gov (United States)

    Kansui, Yasuo; Matsumura, Kiyoshi; Kida, Haruko; Sakata, Satoko; Ohtsubo, Toshio; Ibaraki, Ai; Kitazono, Takanari

    2014-01-01

    Strict control of blood pressure is important to prevent cardiovascular disease, although it is sometimes difficult to decrease blood pressure to target levels. The aim of this study was to investigate the clinical characteristics of resistant hypertension evaluated by ambulatory blood pressure monitoring. One hundred in-hospital patients, whose 24-hour average blood pressure was higher than 130/80 mmHg even after treatment with more than three antihypertensive drugs, were included in the present analysis. Circadian variation of blood pressure was evaluated by nocturnal fall in systolic blood pressure. Average blood pressures of all patients were high in both daytime and nighttime, 150.0/82.9 and 143.8/78.2 mmHg, respectively. Twenty patients had been treated with hemodialysis or peritoneal dialysis. In 63 patients out of the other 80 patients (79%), estimated glomerular filtration rate (eGFR) was also decreased (blood pressure variation only by renal dysfunction. These results show that a large number of the patients with resistant hypertension suffered from renal dysfunction, although it was difficult to explain altered circadian blood pressure variation based on renal dysfunction alone.

  4. 77 FR 69541 - Technical Report Evaluating the Effectiveness of Tire Pressure Monitoring Systems (TPMS) in...

    Science.gov (United States)

    2012-11-19

    ..., Mathematical Statistician, Mathematical Analysis Division, NVS-421, National Center for Statistics and Analysis... report is an analysis of the data collected through the Tire Pressure Monitoring System-Special Study as... Regulatory Analysis and Evaluation. BILLING CODE 4910-59-P ...

  5. Benzoin Condensation: Monitoring a Chemical Reaction by High-Pressure Liquid Chromatography

    Science.gov (United States)

    Bhattacharya, Apurba; Purohit, Vikram C.; Bellar, Nicholas R.

    2004-01-01

    High-pressure liquid chromatography (HPLC) is the preferred method of separating a variety of materials in complex mixtures such as pharmaceuticals, polymers, soils, food products and biological fluids and is also considered to be a powerful analytical tool in both academia and industry. The use of HPLC analysis as a means of monitoring and…

  6. Electronic monitoring of adherence, treatment of hypertension, and blood pressure control

    NARCIS (Netherlands)

    Onzenoort, H.A. van; Verberk, W.J.; Kroon, A.A.; Kessels, A.G.; Neef, C.; Kuy, P.H. van der; Leeuw, P.W. de

    2012-01-01

    BACKGROUND: Although it is generally acknowledged that electronic monitoring of adherence to treatment improves blood pressure (BP) control by increasing patients' awareness to their treatment, little information is available on the long-term effect of this intervention. METHODS: In this observation

  7. Comparison of the oscillometric blood pressure monitor (BPM-100(Beta) ) with the auscultatory mercury sphygmomanometer.

    Science.gov (United States)

    Mattu, G S; Perry, T L; Wright, J M

    2001-06-01

    To compare directly the accuracy of the BPM-100(Beta) monitor (an automated oscillometric blood pressure device) with standard auscultatory mercury sphygmomanometry. The BPM-100(Beta) was connected in parallel via a T-tube to a mercury sphygmomanometer. The BPM-100(Beta) and two trained observers (blinded from each other and from the BPM-100(Beta)) measured the sitting blood pressure simultaneously. Means, standard deviations and ranges were calculated for all the demographic data: age, arm size, heart rate and blood pressure. The agreement between the BPM-100(Beta) and the mean of two observers (the reference) was determined and expressed as the mean +/- SD, as well as the percentage of differences falling within 5, 10 and 15 mmHg. Of the 92 subjects recruited, 85 (92.4%) met the inclusion criteria, and 391 sets of sitting blood pressure and heart rate measurements were available for analysis. The mean difference between the BPM-100(Beta) monitor and the reference was -0.62 +/- 6.96 mmHg for systolic blood pressure, -1.48 +/- 4.80 mmHg for diastolic blood pressure and 0.14 +/- 1.86 beats/min for heart rate. The only limitation of the device was its tendency to underestimate higher systolic blood pressures. This problem has been addressed by a minor change in the algorithm (see the companion publication, Blood Press Monit, 6, 161-165, 2001). The BPM-100(Beta) is an accurate blood pressure monitor for the office setting, meeting all requirements of the Association for the Advancement of Medical Instrumentation and achieving an 'A' grade according to the British Hypertension Society protocol.

  8. Continuous Non-Invasive Arterial Pressure Technique Improves Patient Monitoring during Interventional Endoscopy

    Directory of Open Access Journals (Sweden)

    Sylvia Siebig, Felix Rockmann, Karl Sabel, Ina Zuber-Jerger, Christine Dierkes, Tanja Brünnler, Christian E. Wrede

    2009-01-01

    Full Text Available Introduction: Close monitoring of arterial blood pressure (BP is a central part of cardiovascular surveillance of patients at risk for hypotension. Therefore, patients undergoing diagnostic and therapeutic procedures with the use of sedating agents are monitored by discontinuous non-invasive BP measurement (NIBP. Continuous non-invasive BP monitoring based on vascular unloading technique (CNAP®, CN Systems, Graz may improve patient safety in those settings. We investigated if this new technique improved monitoring of patients undergoing interventional endoscopy. Methods: 40 patients undergoing interventional endoscopy between April and December 2007 were prospectively studied with CNAP® in addition to standard monitoring (NIBP, ECG and oxygen saturation. All monitoring values were extracted from the surveillance network at one-second intervals, and clinical parameters were documented. The variance of CNAP® values were calculated for every interval between two NIBP measurements. Results: 2660 minutes of monitoring were recorded (mean 60.1±34.4 min/patient. All patients were analgosedated with midazolam and pethidine, and 24/40 had propofol infusion (mean 90.9±70.3 mg. The mean arterial pressure for CNAP® was 102.4±21.2 mmHg and 106.8±24.8 mmHg for NIBP. Based on the first NIBP value in an interval between two NIBP measurements, BP values determined by CNAP® showed a maximum increase of 30.8±21.7% and a maximum decrease of 22.4±28.3% (mean of all intervals. Discussion: Conventional intermittent blood pressure monitoring of patients receiving sedating agents failed to detect fast changes in BP. The new technique CNAP® improved the detection of rapid BP changes, and may contribute to a better patient safety for those undergoing interventional procedures.

  9. Subharmonic aided pressure estimation for monitoring interstitial fluid pressure in tumours--in vitro and in vivo proof of concept.

    Science.gov (United States)

    Halldorsdottir, V G; Dave, J K; Eisenbrey, J R; Machado, P; Zhao, H; Liu, J B; Merton, D A; Forsberg, F

    2014-09-01

    The feasibility of using subharmonic aided pressure estimation (SHAPE) to noninvasively estimate interstitial fluid pressure (IFP) was studied. In vitro, radiofrequency signals, from 0.2 ml/l of Definity (Lantheus Medical Imaging, N Billerica, MA) were acquired within a water-tank with a Sonix RP ultrasound scanner (Analogic Ultrasound, Richmond, BC, Canada; fT/R=6.7/3.35 MHz and fT/R=10/5 MHz) and the subharmonic amplitudes of the signals were compared over 0-50 mmHg. In vivo, five swine with naturally occurring melanomas were studied. Subharmonic signals were acquired from tumours and surrounding tissue during infusion of Definity and compared to needle-based pressure measurements. Both in vitro and in vivo, an inverse linear relationship between hydrostatic pressure and subharmonic amplitude was observed with r(2)=0.63-0.95; p<0.05, maximum amplitude drop 11.36 dB at 10 MHz and -8 dB, and r(2) as high as 0.97; p<0.02 (10 MHz and -4/-8 dB most promising), respectively, indicating that SHAPE may be useful in monitoring IFP.

  10. Wearable and low-stress ambulatory blood pressure monitoring technology for hypertension diagnosis.

    Science.gov (United States)

    Altintas, Ersin; Takoh, Kimiyasu; Ohno, Yuji; Abe, Katsumi; Akagawa, Takeshi; Ariyama, Tetsuri; Kubo, Masahiro; Tsuda, Kenichiro; Tochikubo, Osamu

    2015-01-01

    We propose a highly wearable, upper-arm type, oscillometric-based blood pressure monitoring technology with low-stress. The low-stress is realized by new developments in the hardware and software design. In the hardware design, conventional armband; cuff, is almost halved in volume thanks to a flexible plastic core and a liquid bag which enhances the fitness and pressure uniformity over the arm. Reduced air bag volume enables smaller motor pump size and battery leading to a thinner, more compact and more wearable unified device. In the software design, a new prediction algorithm enabled to apply less stress (and less pain) on arm of the patient. Proof-of-concept experiments on volunteers show a high accuracy on both technologies. This paper mainly introduces hardware developments. The system is promising for less-painful and less-stressful 24-hour blood pressure monitoring in hypertension managements and related healthcare solutions.

  11. Circulating miRNA-155 is realted to blood pressure monitoring parameters

    Institute of Scientific and Technical Information of China (English)

    WU Ying; HUANG Yu-qing; HUANG Cheng; LI Jie; CAI An-ping; YU Xue-ju; ZHOU Dan

    2016-01-01

    Background Studies have shown that miRNA-155 played an important role in the process of development of hypertension.However,there is no date about miRNA-155 and blood pressure monitoring parameters.Therefore,we examined whether in hypertensive patients the expression level of plasma miRNA-155 related to 24-h ambulatory blood pressure monitoring (ABPM) parameters.Methods A cohort of adult patients scheduled to receive physical examination,office and ambulatory blood pressure monitoring.Quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) was used to evaluate the expression of selected miRNA-155.The miRNA-155 expression level correlation between blood pressure parameters was assessed using the Spearman correlation coefficient.Results Fifty four essential hypertension patients (25 men;mean age,53.28 ± 9.52 years) and thirty healthy volunteers (15 men;mean age,53.03 ± 5.87 years) were included.We observed higher expression level of miRNA-155 (32.31 ± 2.85 vs 27.21 ± 1.59,P < 0.001) in hypertensive patients compared to healthy control individuals.MiRNA-155 expression level showed significant positive correlation with 24 h Daytime SBP (r =0.681,P < 0.001),24 h Daytime DBP (r =0.473,P < 0.001),24 h Daytime PP (r =0.565,P < 0.001) and dipping (r =0.257,P =0.018),respectively.Conclusions Our study showed that miRNA-155 expression level was associated positively with daytime blood pressure monitoring parameters,as well as blood pressure variability,indicating a possible implication of miRNA-155 in the pathogenesis of hypertension.

  12. Demonstration of a Packaged Capacitive Pressure Sensor System Suitable for Jet Turbofan Engine Health Monitoring

    Science.gov (United States)

    Scardelletti, Maximilian C.; Jordan, Jennifer L.; Meredith, Roger D.; Harsh, Kevin; Pilant, Evan; Usrey, Michael W.; Beheim, Glenn M.; Hunter, Gary W.; Zorman, Christian A.

    2016-01-01

    In this paper, the development and characterization of a packaged pressure sensor system suitable for jet engine health monitoring is demonstrated. The sensing system operates from 97 to 117 MHz over a pressure range from 0 to 350 psi and a temperature range from 25 to 500 deg. The sensing system consists of a Clapp-type oscillator that is fabricated on an alumina substrate and is comprised of a Cree SiC MESFET, MIM capacitors, a wire-wound inductor, chip resistors and a SiCN capacitive pressure sensor. The pressure sensor is located in the LC tank circuit of the oscillator so that a change in pressure causes a change in capacitance, thus changing the resonant frequency of the sensing system. The chip resistors, wire-wound inductors and MIM capacitors have all been characterized at temperature and operational frequency, and perform with less than 5% variance in electrical performance. The measured capacitive pressure sensing system agrees very well with simulated results. The packaged pressure sensing system is specifically designed to measure the pressure on a jet turbofan engine. The packaged system can be installed by way of borescope plug adaptor fitted to a borescope port exposed to the gas path of a turbofan engine.

  13. Intracranial pressure monitoring in pediatric and adult patients with hydrocephalus and tentative shunt failure: a single-center experience over 10 years in 146 patients.

    Science.gov (United States)

    Sæhle, Terje; Eide, Per Kristian

    2015-05-01

    OBJECT In patients with hydrocephalus and shunts, lasting symptoms such as headache and dizziness may be indicative of shunt failure, which may necessitate shunt revision. In cases of doubt, the authors monitor intracranial pressure (ICP) to determine the presence of over- or underdrainage of CSF to tailor management. In this study, the authors reviewed their experience of ICP monitoring in shunt failure. The aims of the study were to identify the complications and impact of ICP monitoring, as well as to determine the mean ICP and characteristics of the cardiac-induced ICP waves in pediatric versus adult over- and underdrainage. METHODS The study population included all pediatric and adult patients with hydrocephalus and shunts undergoing diagnostic ICP monitoring for tentative shunt failure during the 10-year period from 2002 to 2011. The patients were allocated into 3 groups depending on how they were managed following ICP monitoring: no drainage failure, overdrainage, or underdrainage. While patients with no drainage failure were managed conservatively without further actions, over- or underdrainage cases were managed with shunt revision or shunt valve adjustment. The ICP and ICP wave scores were determined from the continuous ICP waveforms. RESULTS The study population included 71 pediatric and 75 adult patients. There were no major complications related to ICP monitoring, but 1 patient was treated for a postoperative superficial wound infection and another experienced a minor bleed at the tip of the ICP sensor. Following ICP monitoring, shunt revision was performed in 74 (51%) of 146 patients, while valve adjustment was conducted in 17 (12%) and conservative measures without any actions in 55 (38%). Overdrainage was characterized by a higher percentage of episodes with negative mean ICP less than -5 to -10 mm Hg. The ICP wave scores, in particular the mean ICP wave amplitude (MWA), best differentiated underdrainage. Neither mean ICP nor MWA levels showed any

  14. Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

    Directory of Open Access Journals (Sweden)

    Dembinski Rolf

    2009-04-01

    Full Text Available Abstract Background Piezoresistive pressure measurement technique (PRM has previously been applied for direct IAP measurement in a porcine model using two different devices. Aim of this clinical study was to assess both devices regarding complications, reliability and agreement with IVP in patients undergoing elective abdominal surgery. Methods A prospective cohort study was performed in 20 patients randomly scheduled to receive PRM either by a Coach®-probe or an Accurate++®-probe (both MIPM, Mammendorf, Germany. Probes were placed on the greater omentum and passed through the abdominal wall paralleling routine drainages. PRM was compared with IVP measurement by t-testing and by calculating mean difference as well as limits of agreement (LA. Results There were no probe related complications. Due to technical limitations, data could be collected in 3/10 patients with Coach® and in 7/10 patients with Accurate++®. Analysis was carried out only for Accurate++®. Mean values did not differ to mean IVP values. Mean difference to IVP was 0.1 ± 2.8 mmHg (LA: -5.5 to 5.6 mmHg. Conclusion Direct IAP measurement was clinically uneventful. Although results of Accurate++® were comparable to IVP, the device might be too fragile for IAP measurements in the clinical setting. Local ethical committee trial registration: EK2024

  15. Direct intra-abdominal pressure monitoring via piezoresistive pressure measurement: a technical note

    Science.gov (United States)

    Otto, Jens; Kaemmer, Daniel; Binnebösel, Marcel; Jansen, Marc; Dembinski, Rolf; Schumpelick, Volker; Schachtrupp, Alexander

    2009-01-01

    Background Piezoresistive pressure measurement technique (PRM) has previously been applied for direct IAP measurement in a porcine model using two different devices. Aim of this clinical study was to assess both devices regarding complications, reliability and agreement with IVP in patients undergoing elective abdominal surgery. Methods A prospective cohort study was performed in 20 patients randomly scheduled to receive PRM either by a Coach®-probe or an Accurate++®-probe (both MIPM, Mammendorf, Germany). Probes were placed on the greater omentum and passed through the abdominal wall paralleling routine drainages. PRM was compared with IVP measurement by t-testing and by calculating mean difference as well as limits of agreement (LA). Results There were no probe related complications. Due to technical limitations, data could be collected in 3/10 patients with Coach® and in 7/10 patients with Accurate++®. Analysis was carried out only for Accurate++®. Mean values did not differ to mean IVP values. Mean difference to IVP was 0.1 ± 2.8 mmHg (LA: -5.5 to 5.6 mmHg). Conclusion Direct IAP measurement was clinically uneventful. Although results of Accurate++® were comparable to IVP, the device might be too fragile for IAP measurements in the clinical setting. Local ethical committee trial registration: EK2024 PMID:19383161

  16. Cost estimation of hypertension management based on home blood pressure monitoring alone or combined office and ambulatory blood pressure measurements.

    Science.gov (United States)

    Boubouchairopoulou, Nadia; Karpettas, Nikos; Athanasakis, Kostas; Kollias, Anastasios; Protogerou, Athanase D; Achimastos, Apostolos; Stergiou, George S

    2014-10-01

    This study aims at estimating the resources consumed and subsequent costs for hypertension management, using home blood pressure (BP) monitoring (HBPM) alone versus combined clinic measurements and ambulatory blood pressure monitoring (C/ABPM). One hundred sixteen untreated hypertensive subjects were randomized to use HBPM or C/ABPM for antihypertensive treatment initiation and titration. Health resources utilized within 12-months follow-up, their respective costs, and hypertension control were assessed. The total cost of the first year of hypertension management was lower in HBPM than C/ABPM arm (€1336.0 vs. €1473.5 per subject, respectively; P cost was identical in both arms. There was no difference in achieved BP control and drug expenditure (HBPM: €233.1 per subject; C/ABPM: €247.6 per subject; P = not significant), whereas the cost of BP measurements and/or visits was higher in C/ABPM arm (€393.9 vs. €516.9, per patient, respectively P cost for subsequent years (>1) was €348.9 and €440.2 per subject, respectively for HBPM and C/ABPM arm and €2731.4 versus €3234.3 per subject, respectively (P cost than C/ABPM, and the same trend is observed in 5-year projection. The results on the resources consumption can be used to make cost estimates for other health-care systems.

  17. Variation in intracranial pressure monitoring and outcomes in pediatric traumatic brain injury.

    Science.gov (United States)

    Bennett, Tellen D; Riva-Cambrin, Jay; Keenan, Heather T; Korgenski, E Kent; Bratton, Susan L

    2012-07-01

    To describe between-hospital and patient-level variation in intracranial pressure (ICP) monitoring and to evaluate ICP monitoring in association with hospital features and outcome in children with traumatic brain injury (TBI). Retrospective cohort study. SETTING Children's hospitals participating in the Pediatric Health Information System database (January 2001 to June 2011). Children (aged head Abbreviated Injury Scale scores of at least 3 who were ventilated for at least 96 consecutive hours or who died in the first 4 days after hospital admission. Monitoring of ICP. A total of 4667 children met the study criteria. Hospital mortality was 41% (n = 1919). Overall, 55% of patients (n = 2586) received ICP monitoring. Expected hospital ICP monitoring rates after adjustment for patient age, cardiac arrest, inflicted injury, craniotomy or craniectomy, head Abbreviated Injury Scale score, and Injury Severity Score were 47% to 60%. Observed hospital ICP monitoring rates were 14% to 83%. Hospitals with more observed ICP monitoring, relative to expected, and hospitals with higher patient volumes had lower rates of mortality or severe disability. After adjustment for between-hospital variation and patient severity of injury, ICP monitoring was independently associated with age 1 year and older (odds ratio, 3.1; 95% CI, 2.5-3.8) vs age younger than 1 year. There was significant between-hospital variation in ICP monitoring that cannot be attributed solely to differences in case mix. Hospitals that monitor ICP more frequently and hospitals with higher patient volumes had better patient outcomes. Infants with TBI are less likely to receive ICP monitoring than are older children.

  18. Non-constrained blood pressure monitoring using ECG and PPG for personal healthcare.

    Science.gov (United States)

    Yoon, Youngzoon; Cho, Jung H; Yoon, Gilwon

    2009-08-01

    Blood pressure (BP) is one of the important vital signs that need to be monitored for personal healthcare. Arterial blood pressure (BP) was estimated from pulse transit time (PTT) and PPG waveform. PTT is a time interval between an R-wave of electrocardiography (ECG) and a photoplethysmography (PPG) signal. This method does not require an aircuff and only a minimal inconvenience of attaching electrodes and LED/photo detector sensors on a subject. PTT computed between the ECG R-wave and the maximum first derivative PPG was strongly correlated with systolic blood pressure (SBP) (R = -0.712) compared with other PTT values, and the diastolic time proved to be appropriate for estimation diastolic blood pressure (DBP) (R = -0.764). The percent errors of SBP using the individual regression line (4-11%) were lower than those using the regression line obtained from all five subjects (9-14%). On the other hand, the DBP estimation did not show much difference between the individual regression (4-10%) and total regression line (6-10%). Our developed device had a total size of 7 x 13.5 cm and was operated by single 3-V battery. Biosignals can be measured for 72 h continuously without external interruptions. Through a serial network communication, an external personal computer can monitor measured waveforms in real time. Our proposed method can be used for non-constrained, thus continuous BP monitoring for the purpose of personal healthcare.

  19. [Influence of treatment with olmesartan on ambulatory blood pressure monitoring parameters in patients with arterial hypertension].

    Science.gov (United States)

    Bregvadze, T R; Tseluĭko, V I; Mishchuk, N E

    2013-12-01

    Hypertension is the most common disease of the cardiovascular system. Active treatment of hypertension with adequate control of blood pressure (BP) can prevent complications, improve life quality and increase life expectancy. One of the interesting new antihypertensive agents, from the group of angiotensin receptor blockers is olmesartan. The obvious advantages of ambulatory blood pressure monitoring to traditional one-time measurements of BP make this method perspective for quality control of anti-hypertensive therapy. The aim of this study was to evaluate the influence of treatment with olmesartan on ambulatory blood pressure monitoring parameters in patients with hypertension. 38 out-patients with hypertension at the age of 25-84 years (mean 55,3±10,6) were studied. Patients received olmesartan 20 mg daily as monotherapy (20 patients (52,6%)) or in combination with other antihypertensive agents (18 patients (47,4%)). Treatment continued for 6 months. The complex examination included: measurement of office brachial BP, electrocardiography, echocardiography and ambulatory blood pressure monitoring (ABPM). As a result of treatment, office BP and diurnal BP, according to ABPM, significantly decreased; the favorable circadian BP profile dynamics were found: significantly less frequently observed lack of reduction in BP during night (daily index - non-dipper) - 18% vs. 64% (p treatment of hypertensive patients with olmesartan provides significant decline not only in office BP, but also in diurnal BP, normalizes BP of active and passive periods, also - daily index and reduces BP variability.

  20. Pressure-Saturation Effects from AVO Attributes in CO2 Monitoring of Weyburn Reservoir, Saskatchewan, Canada

    Science.gov (United States)

    Gao, L.; Morozov, I. B.

    2011-12-01

    In order to measure pore-pressure and saturation effects due to CO2 injection, amplitude variation with offset (AVO) could be a most valuable discriminator. The AVO technique is applied to monitoring the Weyburn reservoir, located in southeast Saskatchewan, using 3D/3C surface seismic datasets. A baseline (1999) and two monitor surveys (2001 and 2002) acquired by EnCana as part of the International Energy Agency GHG Weyburn-Midale CO2 Monitoring and Storage Project are included in this study. Two-term linear AVO attributes including the intercept (I), gradient (G), S-wave reflectivity (I-G)/2 and I+G are derived. Attribute I - G is shown to be most sensitive to pressure variations, and I + G - to CO2 saturation. In addition, several secondary attributes based on statistical distributions of (I, G) values are also examined. The time-lapse AVO attributes indicate areas of pore-pressure and potentially CO2 saturation variations between the horizontal injection wells. The results indicate that AVO technology allows estimating reservoir pressure and fluid saturation variations from time-lapse seismic data.

  1. Ambulatory arterial stiffness index derived from 24-hour ambulatory blood pressure monitoring.

    Science.gov (United States)

    Li, Yan; Wang, Ji-Guang; Dolan, Eamon; Gao, Ping-Jin; Guo, Hui-Feng; Nawrot, Tim; Stanton, Alice V; Zhu, Ding-Liang; O'Brien, Eoin; Staessen, Jan A

    2006-03-01

    We hypothesized that 1 minus the slope of diastolic on systolic pressure during 24-hour ambulatory monitoring (ambulatory arterial stiffness index [AASI]) might reflect arterial stiffness. We compared AASI with established measures of arterial stiffness and studied its distribution in Chinese and European populations. We used 90207 SpaceLabs monitors and the SphygmoCor device to measure AASI, central and peripheral pulse pressures, the central (CAIx) and peripheral (PAIx) systolic augmentation indexes, and aortic pulse wave velocity. In 166 volunteers, the correlation coefficient between AASI and pulse wave velocity was 0.51 (Ppressure (r=0.50). AASI increased with age and mean arterial pressure but decreased with body height. Both before and after adjustment for arterial wave reflections by considering height and heart rate as covariates, AASI correlated more (Ppressure. Among normotensive subjects, the 95th percentile of AASI was 0.55 in Chinese and 0.57 in 1617 Europeans enrolled in the International Database on Ambulatory Blood Pressure Monitoring. The upper boundary of the 95% prediction interval of AASI in relation to age ranged from 0.53 at 20 years to 0.72 at 80 years. In conclusion, AASI is a new index of arterial stiffness that can be easily measured under ambulatory conditions. Pending additional validation in outcome studies, normal values of AASI are probably <0.50 and 0.70 in young and older subjects, respectively.

  2. Flying blind: designing and maintaining jointed concrete pavement without monitoring pavement pressure generation

    Science.gov (United States)

    Burke, Martin P., Jr.

    2001-08-01

    The generation of longitudinal pavement pressures or growth of jointed-rigid pavement have been recognized by many engineers for at least a century. The manifestations of this pressure/growth phenomenon, in the form of progressive pavement and bridge damage, are vivid examples of its destructive potential. Yet, only a few researchers have attempted to measure the pressures generated by this phenomenon. None, to the author's knowledge, have attempted to periodically monitor pressure generation for the purpose of either determining and describing pressure generation characteristics or predicting the probability of its abrupt final and destructive manifestations. Because the pavement/growth phenomenon occurs over such a long period of time (a decade or more), it is generally unrecognized, or if recognized, it is poorly understood. Consequently, design and maintenance of jointed rigid pavement continues to be guided more by intuition and personal judgement rather than be replicated research and professional consensus. This paper provides a speculative description of the pavement pressure/growth phenomenon. It also contains an appeal to research professionals to develop instrumentation suitable to monitor generating pavement pressures. The results of such research should finally enable the transportation profession to establish suitable background so that future pavement design and maintenance will be guided so that pressure generation will be minimized and pavement and bridge function and durability will be improved. Otherwise, transportation systems will continue to experience progressive and substantial pavement and bridge damage, commensurate repair costs, and the traveling public will continue to be exposed to occasional but abrupt manifestations of its destructive potential.

  3. Ambulatory blood pressure monitoring early after acute myocardial infarction: development of a new prognostic index.

    Science.gov (United States)

    Antonini, Lanfranco; Pasceri, Vincenzo; Greco, Salvatore; Colivicchi, Furio; Malfatti, Solferina; Pede, Sergio; Guido, Vincenzo; Kol, Amir; Santini, Massimo

    2007-04-01

    The aim of our study was to assess the possible role of a prognostic index based on ambulatory blood pressure monitoring in a large cohort of patients with recent myocardial infarction. The study population included 1335 consecutive patients admitted for ST elevation myocardial infarction and discharged alive from 48 Italian hospitals participating in the multicentric IMPRESSIVE (Infarto Miocardico, Pressione arteriosa e frequenza cardiaca. Studio Italiano di Valutazione Epidemiologica) study. Ambulatory blood pressure monitoring was performed 3 weeks after discharge, with a clinical follow-up of 12 months. End-points included cardiac death and new admission for heart failure. A prognostic index was obtained from the ambulatory blood pressure monitoring variables according to the formula: (220-age)-mean 24 h heart rate (m24hHR)+mean 24 h diastolic blood pressure (m24hDBP). Among many potential predictors only left-ventricular ejection fraction, creatinine levels, Killip class and the prognostic index were independently associated with events during the follow-up. In particular, higher values of the prognostic index were associated with a lower incidence of events, with an odds ratio of 0.958 (95% confidence intervals 0.943-0.974) and a 4% reduction in risk for each point of the prognostic index. Overall incidence of cardiac events was 6-fold higher in patients within the lowest quartile of the prognostic index (< or =148) compared with the other three quartiles (12 vs. 2, 1.4 and 2% respectively in the other three quartiles; P<0.0001). A simple prognostic index based on ambulatory blood pressure monitoring and age may be a useful tool in predicting cardiac death and heart failure in patients with recent myocardial infarction.

  4. Use of paravascular admittance waveforms to monitor relative change in arterial blood pressure

    Science.gov (United States)

    Zielinski, Todd M.; Hettrick, Doug; Cho, Yong

    2010-04-01

    Non-invasive methods to monitor ambulatory blood pressure often have limitations that can affect measurement accuracy and patient adherence [1]. Minimally invasive measurement of a relative blood pressure surrogate with an implantable device may provide a useful chronic diagnostic and monitoring tool. We assessed a technique that uses electrocardiogram and paravascular admittance waveform morphology analysis to one, measure a time duration (vascular tone index, VTI in milliseconds) change from the electrocardiogram R-wave to admittance waveform peak and two, measure the admittance waveform minimum, maximum and magnitude as indicators of change in arterial compliance/distensibility or pulse pressure secondary to change in afterload. Methods: Five anesthetized domestic pigs (32 ± 4.2 kg) were used to study the effects of phenylephrine (1-5 ug/kg/min) on femoral artery pressure and admittance waveform morphology measured with a quadrapolar electrode array catheter placed next to the femoral artery to assess the relative change in arterial compliance due to change in peripheral vascular tone. Results: Statistical difference was observed (p blood pressure may be suitable for implantable devices to detect progression of cardiovascular disease such as hypertension.

  5. Battery-Free Smart Sock for Abnormal Relative Plantar Pressure Monitoring.

    Science.gov (United States)

    Lin, Xiaoyou; Seet, Boon-Chong

    2017-04-01

    This paper presents a new design of a wearable plantar pressure monitoring system in the form of a smart sock for sensing abnormal relative pressure changes. One advantage of this approach is that with a battery-free design, this system can be powered solely by radio frequency (RF) energy harvested from a radio frequency identification (RFID) reader unit hosted on a smartphone of the wearer. At the same time, this RFID reader can read foot pressure values from an embedded sensor-tag in the sock. A pressure sensing matrix made of conductive fabric and flexible piezo-resistive material is integrated into the sock during the knitting process. Sensed foot pressures are digitized and stored in the memory of a sensor-tag, thus allowing relative foot pressure values to be tracked. The control unit of the smart sock is assembled on a flexible printed circuit board (FPC) that can be strapped to the lower limb and detached easily when it is not in use. Experiments show that the system can operate reliably in both tasks of RF energy harvesting and pressure measurement.

  6. Application of Nexfin noninvasive beat-to-beat arterial blood pressure monitoring in autonomic function testing.

    Science.gov (United States)

    Sipkens, Laura M; Treskes, Kaij; Ariese-Beldman, Karin; Veerman, Derk P; Boer, Christa

    2011-10-01

    Evaluation of autonomic function responses is increasingly important for risk prediction and hemodynamic evaluation in the ambulant and perioperative setting, but requires a noninvasive arterial blood pressure measurement device. This study describes whether a novel noninvasive beat-to-beat arterial blood pressure measurement device (Nexfin HD) is able to reproducibly reflect autonomic function responses in healthy volunteers. Noninvasive beat-to-beat arterial blood pressure measurements (Nexfin HD) were performed in 20 healthy men of 22 ± 3 years. Measurements were performed during supine steady state, controlled breathing (0.125 Hz), passive leg raising, a controlled Valsalva maneuver, and a quick stand test. Finally, relative changes in pulse pressure during autonomic function testing and the test-retest reproducibility were determined. Autonomic function tests induced beat-to-beat arterial blood pressure changes that were accurately monitored by the Nexfin device. The intraclass correlation coefficients for systolic and diastolic arterial blood pressure measurements during supine steady state were agreeable [0.91 (0.82-0.96) and 0.84 (0.69-0.93), respectively]. The reproducibility of blood pressure changes during controlled breathing, passive leg raising, and Valsalva maneuver averaged 0.92 (0.82-0.96), 0.76 (0.50-0.90), and 0.94 (0.89-0.97), respectively. The reproducibility of the pulse pressure variation (PPV) as calculated from controlled breathing-induced changes in the arterial blood pressure (13 ± 5%) was high [0.96 (0.93-0.98)]. This study shows that noninvasive beat-to-beat Nexfin HD arterial blood pressure measurements reproducibly reflect autonomic function responses in healthy volunteers.

  7. Advances in Intracranial Pressure Monitoring and Its Significance in Managing Traumatic Brain Injury

    Directory of Open Access Journals (Sweden)

    Usmah Kawoos

    2015-12-01

    Full Text Available Intracranial pressure (ICP measurements are essential in evaluation and treatment of neurological disorders such as subarachnoid and intracerebral hemorrhage, ischemic stroke, hydrocephalus, meningitis/encephalitis, and traumatic brain injury (TBI. The techniques of ICP monitoring have evolved from invasive to non-invasive—with both limitations and advantages. Some limitations of the invasive methods include short-term monitoring, risk of infection, restricted mobility of the subject, etc. The invasiveness of a method limits the frequency of ICP evaluation in neurological conditions like hydrocephalus, thus hampering the long-term care of patients with compromised ICP. Thus, there has been substantial interest in developing noninvasive techniques for assessment of ICP. Several approaches were reported, although none seem to provide a complete solution due to inaccuracy. ICP measurements are fundamental for immediate care of TBI patients in the acute stages of severe TBI injury. In severe TBI, elevated ICP is associated with mortality or poor clinical outcome. ICP monitoring in conjunction with other neurological monitoring can aid in understanding the pathophysiology of brain damage. This review article presents: (a the significance of ICP monitoring; (b ICP monitoring methods (invasive and non-invasive; and (c the role of ICP monitoring in the management of brain damage, especially TBI.

  8. Advances in Intracranial Pressure Monitoring and Its Significance in Managing Traumatic Brain Injury.

    Science.gov (United States)

    Kawoos, Usmah; McCarron, Richard M; Auker, Charles R; Chavko, Mikulas

    2015-12-04

    Intracranial pressure (ICP) measurements are essential in evaluation and treatment of neurological disorders such as subarachnoid and intracerebral hemorrhage, ischemic stroke, hydrocephalus, meningitis/encephalitis, and traumatic brain injury (TBI). The techniques of ICP monitoring have evolved from invasive to non-invasive-with both limitations and advantages. Some limitations of the invasive methods include short-term monitoring, risk of infection, restricted mobility of the subject, etc. The invasiveness of a method limits the frequency of ICP evaluation in neurological conditions like hydrocephalus, thus hampering the long-term care of patients with compromised ICP. Thus, there has been substantial interest in developing noninvasive techniques for assessment of ICP. Several approaches were reported, although none seem to provide a complete solution due to inaccuracy. ICP measurements are fundamental for immediate care of TBI patients in the acute stages of severe TBI injury. In severe TBI, elevated ICP is associated with mortality or poor clinical outcome. ICP monitoring in conjunction with other neurological monitoring can aid in understanding the pathophysiology of brain damage. This review article presents: (a) the significance of ICP monitoring; (b) ICP monitoring methods (invasive and non-invasive); and (c) the role of ICP monitoring in the management of brain damage, especially TBI.

  9. DAILY BLOOD PRESSURE MONITORING AND ARTERIAL RIGIDITY DATA IN OSTEOARTHRITIS PATIENTS WITH AND WITHOUT ARTERIAL HYPERTENSION

    Directory of Open Access Journals (Sweden)

    I.A. Kharitonova

    2009-03-01

    Full Text Available We have compared the daily blood pressure monitoring data with arterial wall rigidity parameters in patients with osteoarthritis with and without arterial hypertension. In 32% of patients with osteoarthritis without arterial hypertension we have determined “non-dipper” type and in 16% of patients - “night-peaker”. In case of arterial hypertension 42,8% of patients with osteoarthritis have “night-peaker” type and 22,8% of patients have “non-dipper” type. We have found the correlation between augmentation indices and daily blood pressure parameters.

  10. Flexible polymer transistors with high pressure sensitivity for application in electronic skin and health monitoring

    Science.gov (United States)

    Schwartz, Gregor; Tee, Benjamin C.-K.; Mei, Jianguo; Appleton, Anthony L.; Kim, Do Hwan; Wang, Huiliang; Bao, Zhenan

    2013-05-01

    Flexible pressure sensors are essential parts of an electronic skin to allow future biomedical prostheses and robots to naturally interact with humans and the environment. Mobile biomonitoring in long-term medical diagnostics is another attractive application for these sensors. Here we report the fabrication of flexible pressure-sensitive organic thin film transistors with a maximum sensitivity of 8.4 kPa-1, a fast response time of 15,000 cycles and a low power consumption of health monitoring and remote diagnostics in cardiovascular medicine.

  11. Double Invasive Blood Pressure Monitoring for Cesarean Delivery in a Pregnant Woman With Aortic Coarctation.

    Science.gov (United States)

    Barcellos, Bruno Mendonça; Loureiro, Fernanda Martins; Sampaio, Livia Fernandes; de Resende, Marco Antonio Cardoso

    2016-08-01

    Aortic coarctation is a discrete narrowing of the proximal thoracic aorta. It is poorly tolerated during pregnancy because of its association with hypertension, cerebrovascular accident, and aortic rupture. We report a case of severe uncorrected congenital aortic coarctation in a 31-year-old symptomatic pregnant woman at 29 weeks of gestation who underwent successful cesarean delivery with an epidural anesthetic technique. Transthoracic echocardiography showed a gradient of 75 mm Hg. To avoid undiagnosed arterial hypotension and inadequate uteroplacental flow distal to the coarctation, double (radial and femoral) invasive arterial blood pressure measurement was used to monitor both pre- and postcoarctation arterial blood pressure.

  12. A CMOS-Based Tactile Sensor for Continuous Blood Pressure Monitoring

    CERN Document Server

    Kirstein, K -U; Salo, T; Hagleitner, C; Vancura, T; Hierlemann, A

    2011-01-01

    A monolithic integrated tactile sensor array is presented, which is used to perform non-invasive blood pressure monitoring of a patient. The advantage of this device compared to a hand cuff based approach is the capability of recording continuous blood pressure data. The capacitive, membrane-based sensor device is fabricated in an industrial CMOS-technology combined with post-CMOS micromachining. The capacitance change is detected by a S?-modulator. The modulator is operated at a sampling rate of 128kS/s and achieves a resolution of 12bit with an external decimation filter and an OSR of 128.

  13. Hypothermic total body washout and intracranial pressure monitoring in Stage IV Reye syndrome.

    Science.gov (United States)

    Lansky, L L; Kalavsky, S M; Brackett, C E; Wallas, C H; Reis, R L

    1977-04-01

    The number of children in this report treated with either TBW or exchange transfusions is small. Case mortality rates among children with Reye syndrome in Stage IV coma tends to be exceedingly high, varying from 50 to 100%. Intracranial pressure monitoring with the subarachnoid screw may have been an additional factor in increasing our survival data in three patients in the TBW group, since it provided continuous monitoring of ICP and allowed judicious administration of mannitol intravenously. Survival of five of six patients without neurologic sequelae in the present series has encouraged us to coninue utilization of TBW in children with Stage IV Reye syndrome.

  14. [Assessment of arterial wall stiffness by 24-hour blood pressure monitoring].

    Science.gov (United States)

    Korneva, V A; Kuznetsova, T Yu

    2016-01-01

    Arterial wall stiffness is an early marker of cardiovascular diseases. The gold standard for assessment of the stiffness of large vessels is presently pulse wave velocity (PWV). Work is in progress on the study of the reference values of PWV in people of different genders and ages. 24-hour blood pressure (BP) monitoring is not only a procedure that can estimate diurnal BP variability, but also monitor the indicators of vascular wall stiffness in a number of cases over a 24-hour period. The given review highlights the pathophysiology of arterial stiffness, methods for its assessment, and the aspects of use in therapeutic practice.

  15. Continuous Right Radial Arterial Pressure Monitoring as a Guide to Dissection of a Thoracic Inlet Neurofibroma.

    Science.gov (United States)

    Ravindra, Madhavi Nishtala

    2015-09-01

    Excision of tumors in the thoracic inlet entail a risk of injury to subclavian vessels due to their close proximity. A right radial artery line can sensitively and continuously monitor the occurrence of right subclavian artery compression and warn the surgeon of its proximity and prevent injury. We describe a case of thoracic inlet tumor in a 12-year-old child, wherein the use of radial artery pressure monitoring guided the surgeon to separate the subclavian artery from the tumor to which it was adherent. © The Author(s) 2015.

  16. Accuracy and Precision of Continuous Noninvasive Arterial Pressure Monitoring Compared with Invasive Arterial Pressure: A Systematic Review and Meta-analysis

    National Research Council Canada - National Science Library

    Kim, Sang-Hyun; Lilot, Marc; Sidhu, Kulraj S; Rinehart, Joseph; Yu, Zhaoxia; Canales, Cecilia; Cannesson, Maxime

    2014-01-01

    BACKGROUND:Continuous noninvasive arterial pressure monitoring devices are available for bedside use, but the accuracy and precision of these devices have not been evaluated in a systematic review and meta-analysis...

  17. Accuracy of invasive arterial pressure monitoring in cardiovascular patients: an observational study.

    Science.gov (United States)

    Romagnoli, Stefano; Ricci, Zaccaria; Quattrone, Diego; Tofani, Lorenzo; Tujjar, Omar; Villa, Gianluca; Romano, Salvatore M; De Gaudio, A Raffaele

    2014-11-30

    Critically ill patients and patients undergoing high-risk and major surgery, are instrumented with intra-arterial catheters and invasive blood pressure is considered the "gold standard" for arterial pressure monitoring. Nonetheless, artifacts due to inappropriate dynamic response of the fluid-filled monitoring systems may lead to clinically relevant differences between actual and displayed pressure values. We sought to analyze the incidence and causes of resonance/underdamping phenomena in patients undergoing major vascular and cardiac surgery. Arterial pressures were measured invasively and, according to the fast-flush Gardner's test, each patient was attributed to one of two groups depending on the presence (R-group) or absence (NR-group) of resonance/underdamping. Invasive pressure values were then compared with the non-invasive ones. A total of 11,610 pulses and 1,200 non-invasive blood pressure measurements were analyzed in 300 patients. Ninety-two out of 300 (30.7%) underdamping/resonance arterial signals were found. In these cases (R-group) systolic invasive blood pressure (IBP) average overestimation of non-invasive blood pressure (NIBP) was 28.5 (15.9) mmHg (P pressure in the R-group was -2.2 (10.6) mmHg and, in the NR-group -1.1 (5.8) mmHg. The mean arterial pressure difference was 7.4 (11.2) mmHg in the R-group and 2.3 (6.4) mmHg in the NR-group. A multivariate logistic regression identified five parameters independently associated with underdamping/resonance: polydistrectual arteriopathy (P = 0.0023; OR = 2.82), history of arterial hypertension (P = 0.0214; OR = 2.09), chronic obstructive pulmonary disease (P = 0.198; OR = 2.61), arterial catheter diameter (20 vs. 18 gauge) (P pressure-time ratio, showed an optimum selected cut-off point of 1.67 mmHg/msec with a specificity of 97% (95% CI: 95.13 to 99.47%) and a sensitivity of 77% (95% CI: 67.25 to 85.28%) and an area under the ROC curve by extended trapezoidal rule of 0.88. Physicians should be aware

  18. Application of Pressure Pulse Test Analysis in CO2 Leakage Detection and Monitoring

    Science.gov (United States)

    Shakiba, M.; Hosseini, S. A.

    2015-12-01

    Over the past decade, numerous research and industrial projects have been devoted to investigate the feasibility and efficiency of carbon dioxide capture, storage, and utilization. Besides the studies over the characteristics of candidate formations for CO2 injection, much attention has been paid to answer the environmental concerns regarding the CO2 leak to overlying formations. To first detect and then track a possible CO2 leak, different techniques have been proposed in the literature; however, most of them examine only a small portion of the formation and have a low resolution for early leak detection. To further increase the extent of the investigation zone and to monitor a large section of the formation in more detail, multi-well testing techniques have received a significant attention. Pressure pulse testing is a multi-well test technique in which a pressure signal generated by periods of injection and shut-in from a pulser well is propagated inside the formation, and the corresponding response is recorded at the observer wells. The recorded pressure response is then analyzed to measure the rock and fluid properties and to monitor the possible changes over the time. In this research study, we have applied frequency methods as well as superposition principle to interpret the pressure pulse test data and monitor the changes in transmissibility and storativity of the formation between the well pairs. We have used synthetic reservoir models and numerical reservoir simulations to produce the pressure pulse test data. The analysis of the simulation results indicated that even a small amount of CO2 leak in the investigation zone can have a measurable effect on the calculated storativity and transmissibility factors. This can be of a great importance when an early leak detection is of interest. Moreover, when multiple wells are available in the formation, the distribution of the calculated parameters can visualize the extent of CO2 leak, which has a great

  19. Designing and Constructing Blood Flow Monitoring System to Predict Pressure Ulcers on Heel

    Directory of Open Access Journals (Sweden)

    Akbari H.

    2014-06-01

    Full Text Available Background: A pressure ulcer is a complication related to the need for the care and treatment of primarily disabled and elderly people. With the decrease of the blood flow caused by the pressure loaded, ulcers are formed and the tissue will be wasted with the passage of time. Objective: The aim of this study was to construct blood flow monitoring system on the heel tissue which was under external pressure in order to evaluate the tissue treatment in the ulcer. Methods: To measure the blood flow changes, three infrared optical transmitters were used at the distances of 5, 10, and 15 mm to the receiver. Blood flow changes in heels were assessed in pressures 0, 30, and 60 mmHg. The time features were extracted for analysis from the recorded signal by MATLAB software. Changes of the time features under different pressures were evaluated at the three distances by ANOVA in SPSS software. The level of significance was considered at 0.05. Results: In this study, 15 subjects, including both male and female, with the mean age of 54±7 participated. The results showed that the signal amplitude, power and absolute signal decreased significantly when pressure on the tissue increased in different layers (p<0.05. Heart rate only decreased significantly in pressures more than 30 mmHg (p=0.02. In pressures more than 30 mmHg, in addition to a decrease in the time features, the pattern of blood flow signal changed and it wasn’t the same as noload signal. Conclusion: By detecting the time features, we can reach an early diagnosis to prognosticate the degeneration of the tissue under pressure and it can be recommended as a method to predict bedsores in the heel.

  20. Development of a low pressure chromatographic flow system for monitoring the biodegradation of ofloxacin and ciprofloxacin

    OpenAIRE

    Santos, Inês C.; Mesquita, Raquel R. B.; Amorim, Catarina L.; Castro, Paula M. L.; Rangel,António O. S. S.

    2016-01-01

    In this work, we propose a simple low pressure chromatography method with a high throughput for monitoring the biodegradation of fluoroquinolones. Fluoroquinolones are a class of antibiotics that have been accumulating in the environment as a consequence of their release from different sources, namely hospital waste. It has been found that wastewater treatment plants are not able to completely remove this type of micro-pollutants and so, alternative solutions are necessary. Some biodegradatio...

  1. Ambulatory Blood Pressure Monitoring Profile as a Useful Prognostic Tool in Patients with Primary Hypertension

    OpenAIRE

    Mohamed, A. L.; Katiman, E; Hassan, J Abu

    2003-01-01

    Ambulatory blood pressure monitoring (ABPM) devices are increasingly being used in the assessment of hypertension. The purpose of the study was to investigate patient’s diurnal BP variation and to further determine the differences of BP readings between male and female patients and the effects of age in patients who attended the clinic with essential hypertension. In addition, evidence of relationship between the parameters recorded by 24-hour ABPM was also investigated. This study was conduc...

  2. Continuous monitoring of blood pressure in children and adolescents,a review of the literature.

    Science.gov (United States)

    Mercado, Arlene B

    2008-08-01

    Continuous or ambulatory blood pressure monitoring (CBPM or ABPM) is becoming a useful tool in the early detection of hypertension in children and adolescents. With increased obesity in pediatrics, chronic diseases such as hypertension, diabetes, dyslipidemia and metabolic syndrome which was more commonly seen in adults in the early years, can now be seen in this population. This review provides the clinical reports of the use of CBPM for diagnosis and management of hypertension in the pediatric population.

  3. The tympanic membrane displacement analyser for monitoring intracranial pressure in children

    OpenAIRE

    Gwer, Samson; Sheward, Victoria; Birch, Anthony; Marchbanks, Robert; Idro, Richard; Newton, Charles R.; Kirkham, Fenella J; Lin, Jean-Pierre; Lim, Ming

    2013-01-01

    Purpose Raised intracranial pressure (ICP) is a potentially treatable cause of morbidity and mortality but tools for monitoring are invasive. We sought to investigate the utility of the tympanic membrane displacement (TMD) analyser for non-invasive measurement of ICP in children. Methods We made TMD observations on normal and acutely comatose children presenting to Kilifi District Hospital (KDH) at the rural coast of Kenya and on children on follow-up for idiopathic intracranial hypertension ...

  4. The tympanic membrane displacement analyser for monitoring intracranial pressure in children

    OpenAIRE

    Gwer, Samson; Sheward, Victoria; Birch, Anthony; Marchbanks, Robert; Idro, Richard; Newton, Charles R; Kirkham, Fenella J.; Lin, Jean-Pierre; Lim, Ming

    2013-01-01

    Purpose Raised intracranial pressure (ICP) is a potentially treatable cause of morbidity and mortality but tools for monitoring are invasive. We sought to investigate the utility of the tympanic membrane displacement (TMD) analyser for non-invasive measurement of ICP in children. Methods We made TMD observations on normal and acutely comatose children presenting to Kilifi District Hospital (KDH) at the rural coast of Kenya and on children on follow-up for idiopathic intracranial hypertension ...

  5. A surgical method to improve the homeostasis of CSF for the treatment of Alzheimer’s disease

    Directory of Open Access Journals (Sweden)

    Yang Qin

    2016-11-01

    Full Text Available Reduced cerebrospinal fluid (CSF production and increased resistance to CSF outflow are considered to be associated with aging, and are also characteristics of Alzheimer disease (AD. These changes probably result in a decrease in the efficiency of the mechanism by which CSF removes toxic molecules such as amyloid-β (Aβ and tau from the interstitial fluid space. Soluble Aβ is potently neurotoxic and dysfunction in CSF circulation can accelerate the progression of AD. Current therapies for AD exhibit poor efficiency; therefore, a surgical method to improve the homeostasis of CSF is worthy of investigation. To achieve this, we conceived a novel device, which consists of a ventriculo-peritoneal shunt, an injection port and a portable infusion pump. Artificial CSF is pumped into the ventricles and the artificial CSF composition, infusion modes and pressure threshold of shunting can be adjusted according to the intracranial pressure and CSF contents. We hypothesize that this active treatment for CSF circulation dysfunction will significantly retard the progression of AD.

  6. Clinical application of invasive intracranial pressure monitoring after severe traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Xia LI

    2011-12-01

    Full Text Available Objective The current study aims to investigate the effects of different intracranial pressure(ICP monitoring means on the prognosis of severe traumatic brain injury,and to determine the significance of all kinds of intracranial pressure monitoring methods for treating severe traumatic brain injury clinically.Methods From January 2009 to June 2010,a total of 201 cases of severe traumatic brain injury(STBI who received operation treatment were collected and divided into A,B,and C groups based on the positions of the ICP probes and the placement methods.ICP monitoring probes were placed in the ventricle of the brain,parenchyma,or under the putamen,on the basis of the routine operation.Lumbar puncture was done once a day for three to seven days after operation.The Ncurolymph pressure and ICP value that are simultaneously shown in the ICP monitoring device were recorded to calculate the difference between them and to conduct comparison among the groups.The corresponding dehydration treatment was made based on the ICP value after operation to record the duration of use and dosage of the dehydrating agent,operation time,occurrence of all kinds of complications,and the prognosis of patients,and to create a comparison among the groups.Results The different values between the ICP monitoring values and ncurolymph pressure in the A,B,and C groups were 22.4±3.6,20.8±4.1,and 12.3±11.5 mmH2O,respectively. The dosage and durationof use of mannitol in group C were significantly higher than those in groups A and B(P < 0.01,whereas the incidence of pulmonary infection and electrolyte disturbance in group C was higher than those in groups A and B(P < 0.01.However,no significant difference of prognosis was observed among the three groups.The operating duration of group A was significantly longer than those of groups B and C(P < 0.01.However,the overall prognosis of the patients in the three groups had no significant difference.The operation time of group A was

  7. Low parameter model to monitor bottom hole pressure in vertical multiphase flow in oil production wells

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Ahmadi

    2016-09-01

    Full Text Available The importance of the flow patterns through petroleum production wells proved for upstream experts to provide robust production schemes based on the knowledge about flow behavior. To provide accurate flow pattern distribution through production wells, accurate prediction/representation of bottom hole pressure (BHP for determining pressure drop from bottom to surface play important and vital role. Nevertheless enormous efforts have been made to develop mechanistic approach, most of the mechanistic and conventional models or correlations unable to estimate or represent the BHP with high accuracy and low uncertainty. To defeat the mentioned hurdle and monitor BHP in vertical multiphase flow through petroleum production wells, inventive intelligent based solution like as least square support vector machine (LSSVM method was utilized. The evolved first-break approach is examined by applying precise real field data illustrated in open previous surveys. Thanks to the statistical criteria gained from the outcomes obtained from LSSVM approach, the proposed least support vector machine (LSSVM model has high integrity and performance. Moreover, very low relative deviation between the model estimations and the relevant actual BHP data is figured out to be less than 6%. The output gained from LSSVM model are closed the BHP while other mechanistic models fails to predict BHP through petroleum production wells. Provided solutions of this study explicated that implies of LSSVM in monitoring bottom-hole pressure can indicate more accurate monitoring of the referred target which can lead to robust design with high level of reliability for oil and gas production operation facilities.

  8. Behavior of plant plasma membranes under hydrostatic pressure as monitored by fluorescent environment-sensitive probes.

    Science.gov (United States)

    Roche, Yann; Klymchenko, Andrey S; Gerbeau-Pissot, Patricia; Gervais, Patrick; Mély, Yves; Simon-Plas, Françoise; Perrier-Cornet, Jean-Marie

    2010-08-01

    We monitored the behavior of plasma membrane (PM) isolated from tobacco cells (BY-2) under hydrostatic pressures up to 3.5kbar at 30 degrees C, by steady-state fluorescence spectroscopy using the newly introduced environment-sensitive probe F2N12S and also Laurdan and di-4-ANEPPDHQ. The consequences of sterol depletion by methyl-beta-cyclodextrin were also studied. We found that application of hydrostatic pressure led to a marked decrease of hydration as probed by F2N12S and to an increase of the generalized polarization excitation (GPex) of Laurdan. We observed that the hydration effect of sterol depletion was maximal between 1 and 1.5 kbar but was much less important at higher pressures (above 2 kbar) where both parameters reached a plateau value. The presence of a highly dehydrated gel state, insensitive to the sterol content, was thus proposed above 2.5 kbar. However, the F2N12S polarity parameter and the di-4-ANEPPDHQ intensity ratio showed strong effect on sterol depletion, even at very high pressures (2.5-3.5 kbar), and supported the ability of sterols to modify the electrostatic properties of membrane, notably its dipole potential, in a highly dehydrated gel phase. We thus suggested that BY-2 PM undergoes a complex phase behavior in response to the hydrostatic pressure and we also emphasized the role of phytosterols to regulate the effects of high hydrostatic pressure on plant PM.

  9. Noninvasive arterial blood pressure waveform monitoring using two- element ultrasound system.

    Science.gov (United States)

    Seo, Joohyun; Pietrangelo, Sabino J; Lee, Hae-Seung; Sodini, Charles G

    2015-04-01

    This work details noninvasive arterial blood pressure (ABP) waveform estimation based on an arterial vessel cross-sectional area measurement combined with an elasticity measurement of the vessel, represented by pulse wave velocity (PWV), using a two-element ultrasound system. The overall ABP waveform estimation is validated in a custom-designed experimental setup mimicking the heart and an arterial vessel segment with two single element transducers, assuming a constant hemodynamic system. The estimation of local PWV using the flow-area method produces unbiased elasticity estimation of the tube in a pressure waveform comparison. The measured PWV using 16 cardiac cycles of data is 8.47 + 0.63 m/s with an associated scaling error of -1.56 + 14.0% in a direct pressure waveform comparison, showing negligible bias error on average. The distension waveform obtained from a complex cross-correlation model estimator (C3M) reliably traces small pressure changes reflected by the diameter change. The excellent agreement of an estimated pressure waveform to the reference pressure waveform suggests the promising potential of a readily available, inexpensive, and portable ABP waveform monitoring device.

  10. Dual-modality arterial pulse monitoring system for continuous blood pressure measurement.

    Science.gov (United States)

    Wen-Xuan Dai; Yuan-Ting Zhang; Jing Liu; Xiao-Rong Ding; Ni Zhao

    2016-08-01

    Accurate and ambulatory measurement of blood pressure (BP) is essential for efficient diagnosis, management and prevention of cardiovascular diseases (CVDs). However, traditional cuff-based BP measurement methods provide only intermittent BP readings and can cause discomfort with the occlusive cuff. Although pulse transit time (PTT) method is promising for cuffless and continuous BP measurement, its pervasive use is restricted by its limited accuracy and requirement of placing sensors on multiple body sites. To tackle these issues, we propose a novel dual-modality arterial pulse monitoring system for continuous blood pressure measurement, which simultaneously records the pressure and photoplethysmography (PPG) signals of radial artery. The obtained signals can be used to generate a pressure-volume curve, from which the elasticity index (EI) and viscosity index (VI) can be extracted. Experiments were carried out among 7 healthy subjects with their PPG, ECG, arterial pressure wave and reference BP collected to examine the effectiveness of the proposed indexes. The results of this study demonstrate that a linear regression model combining EI and VI has significantly higher BP tracking correlation coefficient as compared to the PTT method. This suggests that the proposed system and method can potentially be used for convenient and continuous blood pressure estimation with higher accuracy.

  11. Monitoring of injected CO2 at two commercial geologic storage sites with significant pressure depletion and/or re-pressurization histories: A case study

    Directory of Open Access Journals (Sweden)

    Dayanand Saini

    2017-03-01

    The monitoring technologies that have been used/deployed/tested at both the normally pressured West Hastings and the subnormally pressured Bell Creek storage sites appear to adequately address any of the potential “out of zone migration” of injected CO2 at these sites. It would be interesting to see if any of the collected monitoring data at the West Hastings and the Bell Creek storage sites could also be used in future to better understand the viability of initially subnormally pressured and subsequently depleted and re-pressurized oil fields as secure geologic CO2 storage sites with relatively large storage CO2 capacities compared to the depleted and re-pressurized oil fields that were initially discovered as normally pressured.

  12. An intelligent system for continuous blood pressure monitoring on remote multi-patients in real time

    CERN Document Server

    Marani, Roberto

    2012-01-01

    In this paper we present an electronic system to perform a non-invasive measurement of the blood pressure based on the oscillometric method, which does not suffer from the limitations of the well-known auscultatory one. Moreover the proposed system is able to evaluate both the systolic and diastolic blood pressure values and makes use of a microcontroller and a Sallen-Key active filter. With reference to other similar devices, a great improvement of our measurement system is achieved since it performs the transmission of the systolic and diastolic pressure values to a remote computer. This aspect is very important when the simultaneous monitoring of multi-patients is required. The proposed system, prototyped and tested at the Electron Devices Laboratory (Electrical and Information Engineering Department) of Polytechnic University of Bari, Italy, is characterized by originality, by plainness of use and by a very high level of automation (so called intelligent system).

  13. Toward Ubiquitous Blood Pressure Monitoring via Pulse Transit Time: Theory and Practice.

    Science.gov (United States)

    Mukkamala, Ramakrishna; Hahn, Jin-Oh; Inan, Omer T; Mestha, Lalit K; Kim, Chang-Sei; Töreyin, Hakan; Kyal, Survi

    2015-08-01

    Ubiquitous blood pressure (BP) monitoring is needed to improve hypertension detection and control and is becoming feasible due to recent technological advances such as in wearable sensing. Pulse transit time (PTT) represents a well-known potential approach for ubiquitous BP monitoring. The goal of this review is to facilitate the achievement of reliable ubiquitous BP monitoring via PTT. We explain the conventional BP measurement methods and their limitations; present models to summarize the theory of the PTT-BP relationship; outline the approach while pinpointing the key challenges; overview the previous work toward putting the theory to practice; make suggestions for best practice and future research; and discuss realistic expectations for the approach.

  14. Quantitative Raman Spectroscopy to monitor microbial metabolism in situ under pressure

    Science.gov (United States)

    Picard, A.; Daniel, I.; Oger, P.

    2006-12-01

    Although high hydrostatic pressure (HHP) biotopes are ubiquitous on Earth, little is known about the metabolism of piezophile organisms. Cell culture under HHP can be technically challenging, and equipment- dependent. In addition, the depressurization step required for analysis can lead to erroneous data. Therefore, to understand how piezophile organisms react to pressure, it is crucial to be able to monitor their activity in situ under HHP. We developed the use of Quantitative Raman Spectroscopy (QRS, 1) to monitor in situ the metabolism of organic molecules. This technique is based on the specific spectral signature of an analyte from which its concentration can be deduced. An application of this technique to the monitoring of alcoholic fermentation by the piezotolerant micro-eucaryote Saccharomyces cerevisiae is presented. Ethanol fermentation from glucose was monitored during 24h from ambient P up to 100 MPa in the low- pressure Diamond Anvil Cell (lpDAC, 2). The experimental compression chamber consisted in a 300 μm-thick Ni gasket in which a 500 μm-diameter hole was drilled. Early-stationnary yeast cells were inoculated into fresh low-fluorescence medium containing 0.15 M of glucose. Ethanol concentration was determined in situ by QRS using the symmetric C-C stretching mode of ethanol at 878 cm-1 normalizing the data to the intensity of the sulfate S-O stretching mode at 980 cm-1. In our setup, the detection limit of ethanol is lower than 0.05 mM with a precision below 1%. At ambient P, ethanol production in the lpDAC and in control experiments proceeds with the same kinetics. Thus, yeast is not affected by its confinement. This is further confirmed by its ability to bud with a generation time similar to control experiments performed in glass tubes at ambient pressure inside the lpDAC. Ethanol production by yeast occurs to at least 65 MPa (3). At 10 MPa, fermentation proceeds 3 times faster than at ambient P. Fermentation rates decrease linearly from 20 to

  15. Ability of non-invasive intermittent blood pressure monitoring and a continuous non-invasive arterial pressure monitor (CNAP™) to provide new readings in each 1-min interval during elective caesarean section under spinal anaesthesia.

    Science.gov (United States)

    McCarthy, T; Telec, N; Dennis, A; Griffiths, J; Buettner, A

    2012-03-01

    We compared the ability of automated non-invasive intermittent oscillometric blood pressure monitoring with a new device, CNAP(TM) (continuous non-invasive arterial pressure) to provide a new blood pressure reading in each 1-min interval between spinal anaesthesia and delivery during caesarean section. We also compared the accuracy of continuous non-invasive arterial pressure readings with non-invasive blood pressure measurements before spinal anaesthesia. Fifty-nine women participated. The non-invasive and continuous non-invasive monitors displayed new blood pressure readings in a mean of 82% (11%) and 83% (13%) (p = 0.97) of the one-minute intervals between spinal anaesthesia and delivery, respectively. Continuous non-invasive arterial pressure was more likely to fail on two or more consecutive minutes (p=0.001). From the pre-spinal readings, the mean bias, defined as non-invasive-continuous non-invasive arterial pressure, and limits of agreement (±2SD mean bias) for systolic, diastolic and mean blood pressure respectively were +1.3 (±26.0), -2.9 (±21.8) and +2.6 (±20.4) mmHg. The new monitor has disadvantages compared with conventional non-invasive intermittent blood pressure monitoring. Anaesthesia © 2012 The Association of Anaesthetists of Great Britain and Ireland.

  16. OPPORTUNITIES AND ADVANTAGES OF THE 24-HOUR BLOOD PRESSURE MONITORING IN CHILDREN AS PART OF THE OUTPATIENT EXAMINATION

    Directory of Open Access Journals (Sweden)

    A.E. Pal'tseva

    2009-01-01

    Full Text Available The 24 hour blood pressure monitoring has gone beyond the scope of the scientific research for the last decade and is now more widely used in practical healthcare, including pediatrics to identify changes of pressure both towards hypertension and hypotension. It is obviously advantageous to prove pathologic changes in the blood pressure level, as well as to give an objective evaluation of its intensity and duration. This article is devoted to identification of the diagnostic value for the daily blood pressure monitoring outpatient conditions and development of the optimal monitoring regimes to be used among children.Key words: 24 hour blood pressure monitoring, arterial hypertension, arterial hypotension, vegetovascular dystonia, children.

  17. Speaking one's second language under time pressure: an ERP study on verbal self-monitoring in German-Dutch bilinguals.

    Science.gov (United States)

    Ganushchak, Lesya Y; Schiller, Niels O

    2009-03-01

    This study addresses how verbal self-monitoring and the Error-Related Negativity (ERN) are affected by time pressure when a task is performed in a second language as opposed to performance in the native language. German-Dutch bilinguals were required to perform a phoneme-monitoring task in Dutch with and without a time pressure manipulation. We obtained an ERN following verbal errors that showed an atypical increase in amplitude under time pressure. This finding is taken to suggest that under time pressure participants had more interference from their native language, which in turn led to a greater response conflict and thus enhancement of the amplitude of the ERN. This result demonstrates once more that the ERN is sensitive to psycholinguistic manipulations and suggests that the functioning of the verbal self-monitoring system during speaking is comparable to other performance monitoring, such as action monitoring.

  18. Ambulatory and home blood pressure monitoring: gaps between clinical guidelines and clinical practice in Singapore

    Directory of Open Access Journals (Sweden)

    Setia S

    2017-07-01

    Full Text Available Sajita Setia,1 Kannan Subramaniam,2 Boon Wee Teo,3 Jam Chin Tay4 1Chief Medical Office, Medical Affairs, Pfizer Pte Ltd, Singapore; 2Global Medical Affairs, Asia Pacific Region, Pfizer Australia, West Ryde, New South Wales, Australia; 3Department of Medicine, Yong Loo Lin School of Medicine, National University of Singapore, Singapore; 4Department of General Medicine, Tan Tock Seng Hospital, Singapore Purpose: Out-of-office blood pressure (BP measurements (home blood pressure monitoring [HBPM] and ambulatory blood pressure monitoring [ABPM] provide important additional information for effective hypertension detection and management decisions. Therefore, out-of-office BP measurement is now recommended by several international guidelines. This study evaluated the practice and uptake of HBPM and ABPM among physicians from Singapore. Materials and methods: A sample of physicians from Singapore was surveyed between 8 September and 5 October 2016. Those included were in public or private practice had been practicing for ≥3 years, directly cared for patients ≥70% of the time, and treated ≥30 patients for hypertension per month. The questionnaire covered six main categories: general BP management, BP variability (BPV awareness/diagnosis, HBPM, ABPM, BPV management, and associated training needs. Results: Sixty physicians (30 general practitioners, 20 cardiologists, and 10 nephrologists were included (77% male, 85% aged 31–60 years, and mean 22-year practice. Physicians recommended HBPM and ABPM to 81% and 27% of hypertensive patients, respectively. HBPM was most often used to monitor antihypertensive therapy (88% of physicians and 97% thought that ABPM was useful for providing information on BPV. HBPM instructions often differed from current guideline recommendations in terms of frequency, number of measurements, and timing. The proportion of consultation time devoted to discussing HBPM and BPV was one-quarter or less for 73% of physicians, and

  19. Comparing the performance characteristics of CSF-TRUST and CSF-VDRL for syphilis: a cross-sectional study

    Science.gov (United States)

    Gu, Weiming; Yang, Yang; Wu, Lei; Yang, Sheng; Ng, Lai-King

    2013-01-01

    Objective In this study, we aimed to determine the performance characteristics of toluidine red unheated serum test on cerebrospinal fluids (CSF-TRUST) as compared to venereal disease research laboratory test on cerebrospinal fluids (CSF-VDRL) for laboratory the diagnosis of neurosyphilis. Design A cross-sectional study. Setting Sexually transmitted infections (STIs) clinics. Participants and methods CSF and serum samples were collected from 824 individual STD clinic patients who have syphilis and are suspected to progress to neurosyphilis within a 9-month period. CSF-VDRL and CSF-TRUST were performed parallelly on the same day when collected. Treponema pallidum particle agglutination (TPPA) tests were also performed on the CSF and the serum samples, and biochemical analysis of the CSF samples was also performed. Results The overall agreement between CSF-TRUST and CSF-VDRL was 97.3%. The reactive ratios of the CSF samples were 22.1% by CSF-TRUST and 24.8% by CSF-VDRL, respectively. All CSF-TRUST-reactive cases were reactive in the CSF-VDRL. Twenty-two samples with CSF-TRUST-negative were tested CSF-VDRL-reactive with low titres (1 : 1 to 1 : 4). Over 97% of the double-reactive CSF samples (CSF-VDRL and CSF-TRUST) had an identical titre or a titre within a two-fold difference. The agreement of CSF-TPPA and CSF-VDRL was 71.9%. Similarly, the agreement of CSF-TPPA and CSF-TRUST was 69.2%. Conclusions Our results revealed that CSF-TRUST could be used as an option for CSF examination in settings without CSF-VDRL in place. PMID:23430600

  20. Comparing the performance characteristics of CSF-TRUST and CSF-VDRL for syphilis: a cross-sectional study.

    Science.gov (United States)

    Gu, Weiming; Yang, Yang; Wu, Lei; Yang, Sheng; Ng, Lai-King

    2013-01-01

    In this study, we aimed to determine the performance characteristics of toluidine red unheated serum test on cerebrospinal fluids (CSF-TRUST) as compared to venereal disease research laboratory test on cerebrospinal fluids (CSF-VDRL) for laboratory the diagnosis of neurosyphilis. A cross-sectional study. Sexually transmitted infections (STIs) clinics. CSF and serum samples were collected from 824 individual STD clinic patients who have syphilis and are suspected to progress to neurosyphilis within a 9-month period. CSF-VDRL and CSF-TRUST were performed parallelly on the same day when collected. Treponema pallidum particle agglutination (TPPA) tests were also performed on the CSF and the serum samples, and biochemical analysis of the CSF samples was also performed. The overall agreement between CSF-TRUST and CSF-VDRL was 97.3%. The reactive ratios of the CSF samples were 22.1% by CSF-TRUST and 24.8% by CSF-VDRL, respectively. All CSF-TRUST-reactive cases were reactive in the CSF-VDRL. Twenty-two samples with CSF-TRUST-negative were tested CSF-VDRL-reactive with low titres (1 : 1 to 1 : 4). Over 97% of the double-reactive CSF samples (CSF-VDRL and CSF-TRUST) had an identical titre or a titre within a two-fold difference. The agreement of CSF-TPPA and CSF-VDRL was 71.9%. Similarly, the agreement of CSF-TPPA and CSF-TRUST was 69.2%. Our results revealed that CSF-TRUST could be used as an option for CSF examination in settings without CSF-VDRL in place.

  1. Ambulatory and home blood pressure monitoring: gaps between clinical guidelines and clinical practice in Singapore.

    Science.gov (United States)

    Setia, Sajita; Subramaniam, Kannan; Teo, Boon Wee; Tay, Jam Chin

    2017-01-01

    Out-of-office blood pressure (BP) measurements (home blood pressure monitoring [HBPM] and ambulatory blood pressure monitoring [ABPM]) provide important additional information for effective hypertension detection and management decisions. Therefore, out-of-office BP measurement is now recommended by several international guidelines. This study evaluated the practice and uptake of HBPM and ABPM among physicians from Singapore. A sample of physicians from Singapore was surveyed between 8 September and 5 October 2016. Those included were in public or private practice had been practicing for ≥3 years, directly cared for patients ≥70% of the time, and treated ≥30 patients for hypertension per month. The questionnaire covered six main categories: general BP management, BP variability (BPV) awareness/diagnosis, HBPM, ABPM, BPV management, and associated training needs. Sixty physicians (30 general practitioners, 20 cardiologists, and 10 nephrologists) were included (77% male, 85% aged 31-60 years, and mean 22-year practice). Physicians recommended HBPM and ABPM to 81% and 27% of hypertensive patients, respectively. HBPM was most often used to monitor antihypertensive therapy (88% of physicians) and 97% thought that ABPM was useful for providing information on BPV. HBPM instructions often differed from current guideline recommendations in terms of frequency, number of measurements, and timing. The proportion of consultation time devoted to discussing HBPM and BPV was one-quarter or less for 73% of physicians, and only 55% said that they had the ability to provide education on HBPM and BPV. Patient inertia, poor patient compliance, lack of medical consultation time, and poor patient access to a BP machine were the most common challenges for implementing out-of-office BP monitoring. Although physicians from Singapore do recommend out-of-office BP measurement to patients with hypertension, this survey identified several important gaps in knowledge and clinical practice.

  2. [Blood pressure monitoring - Status quo and future : A contribution to the personalized medicine].

    Science.gov (United States)

    Engelmann, L; Kunig, S; Kunig, H

    2016-10-01

    Sustainment of life demands that the heart create sufficient pressure to maintain enough flow to keep the body healthy and oxygenated. Blood pressures can be easily measured, while volume measurements required additional invasive procedures. In analogy to volumetrically determined ejection fraction, a pressure ejection fraction EF(P) may be calculated. When standardized to heart rate and body surface area, a new, effective performance metric may be defined. These metrics enable the long-term monitoring of the critically ill patient. When presented in a performance diagram, the metrics contain prognostic implications and enable a real-time evaluation of the efficacy of therapeutic measures. Until now, pressure-related prognostic statements were based on statistical averages, which by definition apply to groups. With this new analytical approach, we have the ability to provide patient-specific therapeutics in an area of medicine that requires individualized treatment. Here, we show preliminary results of applying a mathematical risk analysis to blood pressure metrics to assess therapeutic risk.

  3. Eddy current monitoring of fatigue crack growth in Zr-2.5% Nb pressure tube

    Science.gov (United States)

    Krause, T. W.; Martin, A. E.; Sheppard, R. R.; Schankula, J. J.

    2000-05-01

    Zr-2.5% wt. Nb pressure tubes (PTs) form the core of the heat transport system in CANDU nuclear reactors. These 6 m long, 100 mm diameter tubes are operated at elevated temperatures (nominally 300 °C) and at pressures that produce hoop stresses that are 25% of the ultimate tensile strength of the PT (120 Mpa). Therefore, detection and characterization of flaws in these components becomes crucial for their continued pressure retaining integrity. If a flaw is detected, however, the cost of PT replacement is expensive. Periodic in-service inspection of a flaw that demonstrates no change in flaw characteristics can be used to allow a pressure tube to remain in-service. This requires confidence in the accuracy and reliability of methods used to inter flaw characteristics. Such confidence can only be developed by comparing nondestructive predictions with results from destructive examinations. In this work, eddy current testing was used to monitor the progressive stages of a fatigue crack, grown through pressure cycling from a notch on the inner surface of a PT. Results from a differential lift-off compensated eddy current probe were used to produce sizing estimates of the crack grown between 35% (base of notch) and 74% of the PT wall. A comparison with a destructive examination of the crack demonstrated sensitivity too changes in crack depth accurate to 5% of the tube wall thickness. Such results, combined with similar information obtained from ultrasonics will increase confidence in interpretation of PT inspection data.

  4. Antiretroviral treatment reduces increased CSF neurofilament protein (NFL) in HIV-1 infection.

    Science.gov (United States)

    Mellgren, A; Price, R W; Hagberg, L; Rosengren, L; Brew, B J; Gisslén, M

    2007-10-09

    Increased levels of the light-chain neurofilament protein (NFL) in CSF provide a marker of CNS injury in several neurodegenerative disorders and have been reported in the AIDS dementia complex (ADC). We examined the effects of highly active antiretroviral treatment (HAART) on CSF NFL in HIV-1-infected subjects with and without ADC who underwent repeated lumbar punctures (LPs). NFL was measured by ELISA (normal reference value NFL at baseline, with a median level of 780 ng/L and an intraquartile range (IQR) of 480 to 7300. After 3 months of treatment, NFL concentrations had fallen to normal in 48% (10/21), and the median decreased to 340 ng/L (IQR NFL levels. Thirty-two subjects had normal NFL at baseline, and all but one remained normal at follow-up. These effects on CSF NFL were seen in association with clinical improvement in ADC patients, decreases in plasma and CSF HIV-1 RNA and CSF neopterin, and increases in blood CD4 T cell counts. HAART seems to halt the neurodegenerative process(es) caused by HIV-1, as shown by the significant decrease in CSF NFL after treatment initiation. CSF NFL may serve as a useful marker in monitoring CNS injury in HIV-1 infection and in evaluating CNS efficacy of antiretroviral therapy.

  5. Inter-relationship between CSF dynamics and CSF to-and-fro movement in the cervical region as assessed by MR velocity imaging with phase encoding in hydrocephalic and normal patients

    Energy Technology Data Exchange (ETDEWEB)

    Kudo, Sumio (Hitachi General Hospital, Ibaraki (Japan)); Wachi, Akihiko; Sato, Kiyoshi; Sumie, Hirotoshi

    1992-04-01

    The to-and-fro velocity of cerebrospinal fluid (CSF) at C-1 and C-2 spinal-cord levels was measured by means of MR velocity-imaging technique, and the correlation of changes in velocity and various biophysical factors influencing the intracranial pressure environment were analyzed. Eight hydrocephalic patients, male and female, of different ages (both infants and adults), and 11 normal volunteers with a similar age range were investigated. The to-and-fro CSF movement was measured by means of phase-shift techniques with a bipolar gradient pulse. The cerebrospinal opening pressure was also recorded in 6 of the 8 hydrocephalic patients, either through a ventricular catheter reservoir or a spinal catheter inserted in the lumbosacral subarachnoid space; the CSF pulse amplitude, the pressure volume index (PVI), and the CSF outflow resistance (Ro) were also evaluated during the procedure. CSF flowed towards caudally in the early systolic phase of a cardiac stroke, but the flow direction was reversed in the early diastolic phase when the maximum flow rate was reached. Although such a flow pattern was commonly observed in all normal and hydrocephalic subjects, whatever the age, there was a marked difference in flow rate between the infants and the pediatric-adults groups, -i.e., it was 5-10 mm/sec for the former and 10-20 mm/sec for the latter. An abnormally high flow rate (33.0 mm/sec) was observed in the hydrocephalic patients when there was a malfunction of the ventriculoperitoneal shunt. A close correlation was found to exist among the changes in the CSF flow velocity, the CSF pressure amplitude, and the CSF outflow resistance (Ro), but not in the PVI. The measurement of the CSF flow velocity by MR velocity imaging appears to have an important role not only in the investigation of CSF dynamics, but also in the diagnosis and treatment of such pathologies as hydrocephalus and ventriculoperitoneal shunt malfunction. (author).

  6. Accuracy and precision of continuous noninvasive arterial pressure monitoring compared with invasive arterial pressure: a systematic review and meta-analysis.

    Science.gov (United States)

    Kim, Sang-Hyun; Lilot, Marc; Sidhu, Kulraj S; Rinehart, Joseph; Yu, Zhaoxia; Canales, Cecilia; Cannesson, Maxime

    2014-05-01

    Continuous noninvasive arterial pressure monitoring devices are available for bedside use, but the accuracy and precision of these devices have not been evaluated in a systematic review and meta-analysis. The authors performed a systematic review and meta-analysis of studies comparing continuous noninvasive arterial pressure monitoring with invasive arterial pressure monitoring. Random-effects pooled bias and SD of bias for systolic arterial pressure, diastolic arterial pressure, and mean arterial pressure were calculated. Continuous noninvasive arterial pressure monitoring was considered acceptable if pooled estimates of bias and SD were not greater than 5 and 8 mmHg, respectively, as recommended by the Association for the Advancement of Medical Instrumentation. Twenty-eight studies (919 patients) were included. The overall random-effect pooled bias and SD were -1.6 ± 12.2 mmHg (95% limits of agreement -25.5 to 22.2 mmHg) for systolic arterial pressure, 5.3 ± 8.3 mmHg (-11.0 to 21.6 mmHg) for diastolic arterial pressure, and 3.2 ± 8.4 mmHg (-13.4 to 19.7 mmHg) for mean arterial pressure. In 14 studies focusing on currently commercially available devices, bias and SD were -1.8 ± 12.4 mmHg (-26.2 to 22.5 mmHg) for systolic arterial pressure, 6.0 ± 8.6 mmHg (-10.9 to 22.9 mmHg) for diastolic arterial pressure, and 3.9 ± 8.7 mmHg (-13.1 to 21.0 mmHg) for mean arterial pressure. The results from this meta-analysis found that inaccuracy and imprecision of continuous noninvasive arterial pressure monitoring devices are larger than what was defined as acceptable. This may have implications for clinical situations where continuous noninvasive arterial pressure is being used for patient care decisions.

  7. Cost-effectiveness of ambulatory blood pressure monitoring in the management of hypertension.

    Science.gov (United States)

    Costa, Diogo; Peixoto Lima, Ricardo

    2017-02-01

    The prevalence of hypertension in Portugal is between 29.1% and 42.2%. International studies show that 13% of individuals have masked hypertension and 13% of diagnoses based on office blood pressure measurements are in fact white coat hypertension. More sensitive and specific blood pressure measuring methods could avoid costs associated with misdiagnosis. The aim of this study was to review the cost-effectiveness of ambulatory blood pressure monitoring (ABPM) compared to other methods in the management of hypertension. We performed a literature search in CMA Infobase, Guidelines Finder, National Guideline Clearinghouse, Bandolier, BMJ Clinical Evidence, the Cochrane Library, DARE, Medline, the Trip Database, SUMSearch and Índex das Revistas Médicas Portuguesas. We researched articles published between January 2005 and August 2015 in Portuguese, English and Spanish, using the MeSH terms "Hypertension", "Blood Pressure Monitoring, Ambulatory" and "Cost-Benefit Analysis" and the Portuguese search terms "Hipertensão", "Monitorização Ambulatorial da Pressão Arterial" and "Análise Custo-Benefício". Levels of evidence and grades of recommendation were attributed according to the Oxford Centre for Evidence-Based Medicine scale. Five hundred and twenty-five articles were identified. We included five original studies and one clinical practice guideline. All of them state that ABPM is the most cost-effective method. Two report better blood pressure control, and a Portuguese study revealed a saving of 23%. The evidence shows that ABPM is cost-effective, avoiding iatrogenic effects and reducing expenditure on treatment (grade of recommendation B). The included studies provide a solid basis, but further evidence of reproducibility is needed in research that is not based mainly on analytical models. Copyright © 2016 Sociedade Portuguesa de Cardiologia. Publicado por Elsevier España, S.L.U. All rights reserved.

  8. Results of ambulatory arterial blood pressure monitoring in children with obesity

    Directory of Open Access Journals (Sweden)

    Faruk Öktem

    2010-12-01

    Full Text Available Objectives: The relationship between obesity and essential hypertension is well known. In this study, we aimed to evaluate ambulatory arterial blood pressure monitoring of obese and non-obese children who had similar demographic characteristics.Materials and methods: Seventy one children and adolescents (n=39 obesity, n=32 controls were studied. Blood pressure of the children were measured by 24 hour ambulatory blood pressure monitoring device.Results: Obese children had significantly higher mean blood pressure values (systolic 121.9±11.7 mmHg, diastolic 70.2±5.3 mmHg than control subjects (systolic 109.3±6.7 mmHg, diastolic 65.1±4.6 mmHg, p0.05. Blood pressure load was found to be increased in obese children compared to the controls (%13.6±12.9 and %2.6±3.4, respectively; p<0.05. Serum total cholesterol and LDL-cholesterol levels of obese children (181.1±33.4 and 131.1±23.1mg/dl were significantly higher than those of the controls (134.3±11.1 and 103.3±14.2 mg/dl, p<0.05.Conclusions: Obesity in children and adolescents should not be regarded as variations of normality, but as abnormality with an extremely high risk for the development of hypertension and hyperlipidemia in adulthood.

  9. Validation of a new algorithm for the BPM-100 electronic oscillometric office blood pressure monitor.

    Science.gov (United States)

    Wright, J M; Mattu, G S; Perry Jr, T L; Gelferc, M E; Strange, K D; Zorn, A; Chen, Y

    2001-06-01

    To test the accuracy of a new algorithm for the BPM-100, an automated oscillometric blood pressure (BP) monitor, using stored data from an independently conducted validation trial comparing the BPM-100(Beta) with a mercury sphygmomanometer. Raw pulse wave and cuff pressure data were stored electronically using embedded software in the BPM-100(Beta), during the validation trial. The 391 sets of measurements were separated objectively into two subsets. A subset of 136 measurements was used to develop a new algorithm to enhance the accuracy of the device when reading higher systolic pressures. The larger subset of 255 measurements (three readings for 85 subjects) was used as test data to validate the accuracy of the new algorithm. Differences between the new algorithm BPM-100 and the reference (mean of two observers) were determined and expressed as the mean difference +/- SD, plus the percentage of measurements within 5, 10, and 15 mmHg. The mean difference between the BPM-100 and reference systolic BP was -0.16 +/- 5.13 mmHg, with 73.7% BPM-100 and reference diastolic BP was -1.41 +/- 4.67 mmHg, with 78.4% BPM-100(Beta) and pass the AAMI standard, and 'A' grade BHS protocol. This study illustrates a new method for developing and testing a change in an algorithm for an oscillometric BP monitor utilizing collected and stored electronic data and demonstrates that the new algorithm meets the AAMI standard and BHS protocol.

  10. Miniature Coplanar Implantable Antenna on Thin and Flexible Platform for Fully Wireless Intracranial Pressure Monitoring System

    Directory of Open Access Journals (Sweden)

    M. Waqas A. Khan

    2017-01-01

    Full Text Available Minimally invasive approach to intracranial pressure monitoring is desired for long-term diagnostics. The monitored pressure is transmitted outside the skull through an implant antenna. We present a new miniature (6 mm × 5 mm coplanar implant antenna and its integration on a sensor platform to establish a far-field data link for the sensor readout at distances of 0.5 to 1 meter. The implant antenna was developed using full-wave electromagnetic simulator and measured in a liquid phantom mimicking the dielectric properties of the human head. It achieved impedance reflection coefficient better than −10 dB from 2.38 GHz to 2.54 GHz which covers the targeted industrial, scientific, and medical band. Experiments resulted in an acceptable peak gain of approximately −23 dBi. The implant antenna was submerged in the liquid phantom and interfaced to a 0.5 mW voltage controlled oscillator. To verify the implant antenna performance as a part of the ICP monitoring system, we recorded the radiated signal strength using a spectrum analyzer. Using a half-wavelength dipole as the receiving antenna, we captured approximately −58.7 dBm signal at a distance of 1 m from the implant antenna which is well above for the reader with sensitivity of −80 dBm.

  11. Acceptance and side effects of ambulatory blood pressure monitoring: evaluation of a new technology.

    Science.gov (United States)

    Beltman, F W; Heesen, W F; Smit, A J; May, J F; Lie, K I; Meyboom-de Jong, B

    1996-09-01

    Ambulatory blood pressure (BP) monitoring is probably becoming a clinically useful procedure for the evaluation of hypertensive patients. Previous reports have shown that the devices are safe and serious side effects are rare. Discomfort and inconveniences associated with its use are more frequent. In this study, patient acceptance of ambulatory blood pressure monitoring (ABPM) was compared with acceptance of other diagnostic procedures and their side effects were assessed. Patients were asked to fill in a form and 129 of 166 patients responded. The acceptance was measured with a visual analogue scale which ranged from 'very annoying' on the left to 'not annoying at all' on the right. All forms were collected anonymously. Mean distance (cm) of the visual likert scale was 8.6 to 9.4 for the diagnostic procedures frequently used in routine patient care. Ambulatory BP measurement (ABPM) scored 6.1 cm. Reported side effects (in 27% of patients) were: plan (9%), skin irritation (8%), noisy device (8%), inconvenience with work (3%), haematoma (2%) and other (4%). Reports from the patients on sleep quality were: 23% normal, 61% minor disturbance, 14% had sleep, and 2% did not sleep at all. It can be concluded that ambulatory BP monitoring was the diagnostic procedure with the lowest patient acceptance. Side effects of this new technology were reported by 27% of patients. However, risks are relatively minor. Sleep disturbances were very frequent and was a serious problem for 16% of patients.

  12. Identification of the Upward Movement of Human CSF In Vivo and its Relation to the Brain Venous System.

    Science.gov (United States)

    Dreha-Kulaczewski, Steffi; Joseph, Arun A; Merboldt, Klaus-Dietmar; Ludwig, Hans-Christoph; Gärtner, Jutta; Frahm, Jens

    2017-03-01

    CSF flux is involved in the pathophysiology of neurodegenerative diseases and cognitive impairment after traumatic brain injury, all hallmarked by the accumulation of cellular metabolic waste. Its effective disposal via various CSF routes has been demonstrated in animal models. In contrast, the CSF dynamics in humans are still poorly understood. Using novel real-time MRI, forced inspiration has been identified recently as a main driving force of CSF flow in the human brain. Exploiting technical advances toward real-time phase-contrast MRI, the current work analyzed directions, velocities, and volumes of human CSF flow within the brain aqueduct as part of the internal ventricular system and in the spinal canal during respiratory cycles. A consistent upward CSF movement toward the brain in response to forced inspiration was seen in all subjects at the aqueduct, in 11/12 subjects at thoracic level 2, and in 4/12 subjects at thoracic level 5. Concomitant analyses of CSF dynamics and cerebral venous blood flow, that is, in epidural veins at cervical level 3, uniquely demonstrated CSF and venous flow to be closely communicating cerebral fluid systems in which inspiration-induced downward flow of venous blood due to reduced intrathoracic pressure is counterbalanced by an upward movement of CSF. The results extend our understanding of human CSF flux and open important clinical implications, including concepts for drug delivery and new classifications and therapeutic options for various forms of hydrocephalus and idiopathic intracranial hypertension.SIGNIFICANCE STATEMENT Effective disposal of brain cellular waste products via CSF has been demonstrated repeatedly in animal models. However, CSF dynamics in humans are still poorly understood. A novel quantitative real-time MRI technique yielded in vivo CSF flow directions, velocities, and volumes in the human brain and upper spinal canal. CSF moved upward toward the head in response to forced inspiration. Concomitant analysis

  13. Neoplastic Meningitis: How MRI and CSF Cytology Are Influenced by CSF Cell Count and Tumor Type

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    P. Prömmel

    2013-01-01

    Full Text Available Background. Although CSF cytology and MRI are standard methods to diagnose neoplastic meningitis (NM, this complication of neoplastic disease remains difficult to detect. We therefore reevaluated the sensitivity of gadolinium (GD-enhanced MRI and cerebrospinal-fluid (CSF-cytology and the relevance of tumor type and CSF cell count. Methods. We retrospectively identified 111 cases of NM diagnosed in our CSF laboratory since 1990 with complete documentation of both MRI and CSF cytology. 37 had haematological and 74 solid neoplasms. CSF cell counts were increased in 74 and normal in 37 patients. Results. In hematological neoplasms, MRI was positive in 49% and CSF cytology in 97%. In solid tumors, the sensitivity of MRI was 80% and of cytology 78%. With normal CSF cell counts, MRI was positive in 59% (50% hematological, 72% solid malignancies and CSF cytology in 76% (92% in hematological, 68% in solid neoplasms. In cases of elevated cell counts, the sensitivity of MRI was 72% (50% for hematological, 83% for solid malignancies and of CSF cytology 91% (100% for haematological and 85% for solid neoplasms. 91% of cytologically positive cases were diagnosed at first and another 7% at second lumbar puncture. Routine protein analyses had a low sensitivity in detecting NM. Conclusions. The high overall sensitivity of MRI was only confirmed for NM from solid tumors and for elevated CSF cell counts. With normal cell counts and haematological neoplasms, CSF-cytology was superior to MRI. None of the analysed routine CSF proteins had an acceptable sensitivity and specificity in detecting leptomeningeal disease.

  14. Ambulatory Blood Pressure Monitoring in the Diagnosis and Treatment of Hypertension.

    Science.gov (United States)

    Islam, Md Shahidul

    2016-12-16

    Clinicians should take initiatives to establish ambulatory blood pressure monitoring (ABPM) services in their own practice, or to ensure that they have access to such services elsewhere. Whenever possible, ABPM should be performed in suitable cases, where it is likely to deliver clinically useful information for making a correct diagnosis, or for tailoring the anti-hypertensive treatment regimen for each individual patient. ABPM is clinically useful, among others, for identifying people with "masked normotension", "masked hypertension", "sleep-time hypertension", and "reduced decline of sleep-time blood pressure". This review briefly outlines the rationales for the use of ABPM, interpretations of the ABPM-derived parameters, and the advantages of ABPM in decision making in the management of hypertension.

  15. A pressure-sensitive carbon black cement composite for traffic monitoring

    KAUST Repository

    Monteiro, A.O.

    2017-08-17

    Recent advances in nanotechnology have guided the development of a new generation of multifunctional construction materials. An example of this are cement-based composites, some of which can be used not just to pave roads but also to monitor them. A cement composite, integrating a carbon black (CB) filler, was used as a piezoresistive sensor to identify different cyclic compressive loadings, at temperatures ranging from 15°C to 45°C. The mechanical essays were performed under realistic conditions using 600cm3 specimens and uniaxial loads typical of automobile traffic. A linear and reversible pressure-sensing performance was found with gauge factors ranging from 40 to 60. Overall, these results show that CB/cement composites can act as stress-sensitive materials for traffic monitoring.

  16. Collaborative Processing of Wearable and Ambient Sensor System for Blood Pressure Monitoring

    Science.gov (United States)

    Nakamura, Masayuki; Nakamura, Jiro; Lopez, Guillaume; Shuzo, Masaki; Yamada, Ichiro

    2011-01-01

    This paper describes wireless wearable and ambient sensors that cooperate to monitor a person’s vital signs such as heart rate and blood pressure during daily activities. Each wearable sensor is attached on different parts of the body. The wearable sensors require a high sampling rate and time synchronization to provide a precise analysis of the received signals. The trigger signal for synchronization is provided by the ambient sensors, which detect the user’s presence. The Bluetooth and IEEE 802.15.4 wireless technologies are used for real-time sensing and time synchronization. Thus, this wearable health-monitoring sensor response is closely related to the context in which it is being used. Experimental results indicate that the system simultaneously provides information about the user’s location and vital signs, and the synchronized wearable sensors successfully measures vital signs with a 1 ms resolution. PMID:22163984

  17. Collaborative Processing of Wearable and Ambient Sensor System for Blood Pressure Monitoring

    Directory of Open Access Journals (Sweden)

    Ichiro Yamada

    2011-06-01

    Full Text Available This paper describes wireless wearable and ambient sensors that cooperate to monitor a person’s vital signs such as heart rate and blood pressure during daily activities. Each wearable sensor is attached on different parts of the body. The wearable sensors require a high sampling rate and time synchronization to provide a precise analysis of the received signals. The trigger signal for synchronization is provided by the ambient sensors, which detect the user’s presence. The Bluetooth and IEEE 802.15.4 wireless technologies are used for real-time sensing and time synchronization. Thus, this wearable health-monitoring sensor response is closely related to the context in which it is being used. Experimental results indicate that the system simultaneously provides information about the user’s location and vital signs, and the synchronized wearable sensors successfully measures vital signs with a 1 ms resolution.

  18. Real-time combustion control and diagnostics sensor-pressure oscillation monitor

    Science.gov (United States)

    Chorpening, Benjamin T.; Thornton, Jimmy; Huckaby, E. David; Richards, George A.

    2009-07-14

    An apparatus and method for monitoring and controlling the combustion process in a combustion system to determine the amplitude and/or frequencies of dynamic pressure oscillations during combustion. An electrode in communication with the combustion system senses hydrocarbon ions and/or electrons produced by the combustion process and calibration apparatus calibrates the relationship between the standard deviation of the current in the electrode and the amplitudes of the dynamic pressure oscillations by applying a substantially constant voltage between the electrode and ground resulting in a current in the electrode and by varying one or more of (1) the flow rate of the fuel, (2) the flow rate of the oxidant, (3) the equivalence ratio, (4) the acoustic tuning of the combustion system, and (5) the fuel distribution in the combustion chamber such that the amplitudes of the dynamic pressure oscillations in the combustion chamber are calculated as a function of the standard deviation of the electrode current. Thereafter, the supply of fuel and/or oxidant is varied to modify the dynamic pressure oscillations.

  19. SMART MONITORING AND DECISION MAKING FOR REGULATING ANNULUS BOTTOM HOLE PRESSURE WHILE DRILLING OIL WELLS

    Directory of Open Access Journals (Sweden)

    M. P. Vega

    Full Text Available Abstract Real time measurements and development of sensor technology are research issues associated with robustness and safety during oil well drilling operations, making feasible the diagnosis of problems and the development of a regulatory strategy. The major objective of this paper is to use an experimental plant and also field data, collected from a basin operation, offshore Brazil, for implementing smart monitoring and decision making, in order to assure drilling inside operational window, despite the commonly observed disturbances that produce fluctuations in the well annulus bottom hole pressure. Using real time measurements, the performance of a continuous automated drilling unit is analyzed under a scenario of varying levels of rate of penetration; aiming pressure set point tracking (inside the operational drilling window and also rejecting kick, a phenomenon that occurs when the annulus bottom hole pressure is inferior to the porous pressure, producing the migration of reservoir fluids into the annulus region. Finally, an empirical model was built, using real experimental data from offshore Brazil basins, enabling diagnosing and regulating a real drilling site by employing classic and advanced control strategies.

  20. Invasive intracranial arterial pressure monitoring during endovascular cerebral aneurysms embolization for cerebral perfusion evaluation.

    Science.gov (United States)

    Netlyukh, Andriy M; Shevaga, Volodymyr M; Yakovenko, Leonid M; Payenok, Angelika V; Salo, Victor M; Kobyletskiy, Oleg Ja

    2015-01-01

    The purpose of the study was to define a method of estimation of cerebral blood flow by a determination of parameters of the hemodynamics during neuroendovascular procedures. Materials and Methods. Extracranial and intracranial mean arterial pressure (MAP) was invasively monitored with the help of a transducing system during an endovascular coiling procedure in 19 patients. The measurements were performed at the tip of the guiding catheter and microcatheter placed into internal carotid artery (ICA) C1 segments and of the microcatheter placed into C4 ICA segments, at different stages of the aneurysm repair. Results. As measured, the diameter of the ICA in the C1 and C4 segments did not differ substantially. MAP in the ICA was determined to be 91.2 ± 9.6 mmHg in the skull cavity, and 102.4 ± 6.3 mmHg outside of the skull cavity, with an average difference of 9.2 ± 3.0 mmHg. Conclusion. The difference in MAP, as measured in the ICA outside and inside the skull cavity, was ascribed to the influence of intracranial pressure. Further investigation is required to check the accuracy of invasive intra-arterial pressure recording for an objective and direct measurement of the cerebral perfusion in reference to the intracranial pressure level.

  1. Real-time combustion control and diagnostics sensor-pressure oscillation monitor

    Science.gov (United States)

    Chorpening, Benjamin T.; Thornton, Jimmy; Huckaby, E. David; Richards, George A.

    2009-07-14

    An apparatus and method for monitoring and controlling the combustion process in a combustion system to determine the amplitude and/or frequencies of dynamic pressure oscillations during combustion. An electrode in communication with the combustion system senses hydrocarbon ions and/or electrons produced by the combustion process and calibration apparatus calibrates the relationship between the standard deviation of the current in the electrode and the amplitudes of the dynamic pressure oscillations by applying a substantially constant voltage between the electrode and ground resulting in a current in the electrode and by varying one or more of (1) the flow rate of the fuel, (2) the flow rate of the oxidant, (3) the equivalence ratio, (4) the acoustic tuning of the combustion system, and (5) the fuel distribution in the combustion chamber such that the amplitudes of the dynamic pressure oscillations in the combustion chamber are calculated as a function of the standard deviation of the electrode current. Thereafter, the supply of fuel and/or oxidant is varied to modify the dynamic pressure oscillations.

  2. A flux monitoring method for easy and accurate flow rate measurement in pressure-driven flows.

    Science.gov (United States)

    Siria, Alessandro; Biance, Anne-Laure; Ybert, Christophe; Bocquet, Lydéric

    2012-03-07

    We propose a low-cost and versatile method to measure flow rate in microfluidic channels under pressure-driven flows, thereby providing a simple characterization of the hydrodynamic permeability of the system. The technique is inspired by the current monitoring method usually employed to characterize electro-osmotic flows, and makes use of the measurement of the time-dependent electric resistance inside the channel associated with a moving salt front. We have successfully tested the method in a micrometer-size channel, as well as in a complex microfluidic channel with a varying cross-section, demonstrating its ability in detecting internal shape variations.

  3. Assessment of the usability of a digital learning technology prototype for monitoring intracranial pressure

    Directory of Open Access Journals (Sweden)

    Lilian Regina de Carvalho

    Full Text Available ABSTRACT Objective: to assess the usability of a digital learning technology prototype as a new method for minimally invasive monitoring of intracranial pressure. Method: descriptive study using a quantitative approach on assessing the usability of a prototype based on Nielsen's ten heuristics. Four experts in the area of Human-Computer interaction participated in the study. Results: the evaluation delivered eight violated heuristics and 31 usability problems in the 32 screens of the prototype. Conclusion: the suggestions of the evaluators were critical for developing an intuitive, user-friendly interface and will be included in the final version of the digital learning technology.

  4. Development of a nuclear technique for monitoring water levels in pressurized vehicles

    Science.gov (United States)

    Singh, J. J.; Davis, W. T.; Mall, G. H.

    1983-01-01

    A new technique for monitoring water levels in pressurized stainless steel cylinders was developed. It is based on differences in attenuation coefficients of water and air for Cs137 (662 keV) gamma rays. Experimentally observed gamma ray counting rates with and without water in model reservoir cylinder were compared with corresponding calculated values for two different gamma ray detection theshold energies. Calculated values include the effects of multiple scattering and attendant gamma ray energy reductions. The agreement between the measured and calculated values is reasonably good. Computer programs for calculating angular and spectral distributions of scattered radition in various media are included.

  5. NASA Prototype All Composite Tank Cryogenic Pressure Tests to Failure with Structural Health Monitoring

    Science.gov (United States)

    Werlink, Rudolph J.; Pena, Francisco

    2015-01-01

    This Paper will describe the results of pressurization to failure of 100 gallon composite tanks using liquid nitrogen. Advanced methods of health monitoring will be compared as will the experimental data to a finite element model. The testing is wholly under NASA including unique PZT (Lead Zirconate Titanate) based active vibration technology. Other technologies include fiber optics strain based systems including NASA AFRC technology, Acoustic Emission, Acellent smart sensor, this work is expected to lead to a practical in-Sutu system for composite tanks.

  6. Research on simulation and experiment of noninvasive intracranial pressure monitoring based on acoustoelasticity effects.

    Science.gov (United States)

    Wu, Jun; He, Wei; Chen, Wei-Min; Zhu, Lian

    2013-01-01

    The real-time monitoring of intracranial pressure (ICP) is very important for craniocerebrally critically ill patients, but it is very difficult to realize long-time monitoring for the traditional invasive method, which very easily infects patients. Many noninvasive methods have emerged, but these have not been able to monitor ICP for long periods in real time, and they are not ready for clinical application. In order to realize long-time, online, real-time, noninvasive monitoring for ICP, a new method based on acoustoelasticity of ultrasound is herein proposed. Experimental models were devised to research the new method for experiment and simulation. Polymethyl methacrylate and hydrogel were adopted for the experiment, and their mechanical properties were very close to the real brain. A numerical solution for acoustoelasticity theory was acquired by simulating calculation based on a finite-element method. This was compared to the experimental value. The results showed a consistent match between theoretical solution and experimental value, with maximum error at most 5%. Thus, the effectiveness of the new method was verified. Theoretical and practical foundation is provided for this new method, and it could be used for animal experimentation or clinical testing in further research.

  7. Blood viscosity monitoring during cardiopulmonary bypass based on pressure-flow characteristics of a Newtonian fluid.

    Science.gov (United States)

    Okahara, Shigeyuki; Zu Soh; Takahashi, Shinya; Sueda, Taijiro; Tsuji, Toshio

    2016-08-01

    We proposed a blood viscosity estimation method based on pressure-flow characteristics of oxygenators used during cardiopulmonary bypass (CPB) in a previous study that showed the estimated viscosity to correlate well with the measured viscosity. However, the determination of the parameters included in the method required the use of blood, thereby leading to high cost of calibration. Therefore, in this study we propose a new method to monitor blood viscosity, which approximates the pressure-flow characteristics of blood considered as a non-Newtonian fluid with characteristics of a Newtonian fluid by using the parameters derived from glycerin solution to enable ease of acquisition. Because parameters used in the estimation method are based on fluid types, bovine blood parameters were used to calculate estimated viscosity (ηe), and glycerin parameters were used to estimate deemed viscosity (ηdeem). Three samples of whole bovine blood with different hematocrit levels (21.8%, 31.0%, and 39.8%) were prepared and perfused into the oxygenator. As the temperature changed from 37 °C to 27 °C, the oxygenator mean inlet pressure and outlet pressure were recorded for flows of 2 L/min and 4 L/min, and the viscosity was estimated. The value of deemed viscosity calculated with the glycerin parameters was lower than estimated viscosity calculated with bovine blood parameters by 20-33% at 21.8% hematocrit, 12-27% at 31.0% hematocrit, and 10-15% at 39.8% hematocrit. Furthermore, deemed viscosity was lower than estimated viscosity by 10-30% at 2 L/min and 30-40% at 4 L/min. Nevertheless, estimated and deemed viscosities varied with a similar slope. Therefore, this shows that deemed viscosity achieved using glycerin parameters may be capable of successfully monitoring relative viscosity changes of blood in a perfusing oxygenator.

  8. Research on simulation and experiment of noninvasive intracranial pressure monitoring based on acoustoelasticity effects

    Directory of Open Access Journals (Sweden)

    Wu J

    2013-08-01

    Full Text Available Jun Wu1, Wei He2, Wei-min Chen1, Lian Zhu21Key Laboratory of Optoelectronic Technology and Systems, 2State Key Laboratory of Power Transmission Equipment and System Security and New Technology, Chongqing University, Chongqing, People’s Republic of ChinaAbstract: The real-time monitoring of intracranial pressure (ICP is very important for craniocerebrally critically ill patients, but it is very difficult to realize long-time monitoring for the traditional invasive method, which very easily infects patients. Many noninvasive methods have emerged, but these have not been able to monitor ICP for long periods in real time, and they are not ready for clinical application. In order to realize long-time, online, real-time, noninvasive monitoring for ICP, a new method based on acoustoelasticity of ultrasound is herein proposed. Experimental models were devised to research the new method for experiment and simulation. Polymethyl methacrylate and hydrogel were adopted for the experiment, and their mechanical properties were very close to the real brain. A numerical solution for acoustoelasticity theory was acquired by simulating calculation based on a finite-element method. This was compared to the experimental value. The results showed a consistent match between theoretical solution and experimental value, with maximum error at most 5%. Thus, the effectiveness of the new method was verified. Theoretical and practical foundation is provided for this new method, and it could be used for animal experimentation or clinical testing in further research.Keywords: medical instruments, noninvasive, intracranial pressure, ultrasonic, acoustoelasticity, biomechanics

  9. The development and validation of a digital peak respiratory pressure monitor and its characteristics in healthy human subjects.

    Science.gov (United States)

    Maruthy, K N; Vaz, M

    1999-04-01

    A digital peak respiratory pressure (DPRP) monitor for determining maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) was developed using a pressure transducer and an analog to digital converter. It was calibrated using a mercury manometer. Human studies were conducted in healthy young adults in order to determine within-subject and inter-individual variability, as well as diurnal variations and gender differences in maximal respiratory pressures. The calibration studies for the instrument indicated that the instrument recorded accurate pressures, with little temporal drift. Within-subject variability was generally low while inter-individual variability was higher and significant. Gender differences were similar to those recorded in literature for other racial groups. The DPRP monitor described is inexpensive, accurate and portable, making it ideal for use at the patient's bedside.

  10. Long-term pressure monitoring with arterial applanation tonometry : a non-invasive alternative during clinical intervention?

    NARCIS (Netherlands)

    Matthys, Koen S; Kalmar, Alain F; Struys, Michel M R F; Mortier, Eric P; Avolio, Alberto P; Segers, Patrick; Verdonck, Pascal R

    2008-01-01

    Arterial tonometry is a non-invasive technique for continuous registration of arterial pressure waveforms. This study aims to assess tonometric blood pressure recording (TBP) as an alternative for invasive long-term bedside monitoring. A prospective study was set up where patients undergoing neurosu

  11. Early detection and treatment of myocardial ischaemia after operation using continual ambulatory arterial pressure monitoring and ECG ST segment analysis.

    Science.gov (United States)

    Edwards, N D; Troy, G; Yeo, W; Jackson, P; Reilly, C S

    1995-10-01

    We report a case in which the use of continual ambulatory arterial pressure monitoring and ECG ST-segment analysis allowed early detection and treatment of myocardial ischaemia in the postoperative period. We believe that this case illustrates the potential value of ambulatory monitoring in the early postoperative period in high-risk patients.

  12. A comparison of noninvasive blood pressure measurement on the wrist with invasive arterial blood pressure monitoring in patients undergoing bariatric surgery.

    Science.gov (United States)

    Hager, Helmut; Mandadi, Goutham; Pulley, Debra; Eagon, J Chris; Mascha, Edward; Nutter, Benjamin; Kurz, Andrea

    2009-06-01

    In morbidly obese patients, oscillometric blood pressure measurements with an upper-arm cuff are often difficult to perform. The alternative method, invasive blood pressure monitoring, can be difficult to place and is associated with risks. A wrist-mounted blood pressure-monitoring device, the Vasotrac, provides accurate blood pressure measurements in lean patients. Even in the obese, wrist morphology remains relatively unchanged. We thus assessed the degree to which blood pressure measurements with the Vasotrac on the wrist and cuff measurements agree with invasive arterial blood pressure monitoring. We evaluated 22 morbidly obese patients undergoing bariatric surgery lasting 3.8+/-1.1 h. Intraoperative blood pressure was simultaneously measured using the Vasotrac mounted on one wrist; an arterial catheter was inserted in the opposite radial artery, and an oscillometric cuff was positioned on the upper arm. Preoperative patient comfort was evaluated on a scale from 1 to 10, with 10 being most uncomfortable, just after the first oscillometric cuff inflation. Values from the Vasotrac and arterial catheter were recorded at 5-s intervals. Bias, precision, and clinically acceptable agreement were calculated between the two continuous monitoring devices and between the arterial catheter and the cuff measurements, with the arterial catheter providing the reference value. The patients' age was 44.3+/-9.5 years (mean+/-SD), body mass index was 66.7+/-13.8 kg/m2, and arm circumference was 48.6+/-7.5 cm. Patients found the Vasotrac more comfortable than the oscillometric device [1.7+/-1.8 vs 5.3+/-0.5 (P=0.009)]. A total of 40,411 pairs of values from the Vasotrac and arterial catheter were recorded. Lin's concordance correlation coefficient (95% CI) for mean arterial blood pressure measured between the arterial line and the Vasotrac was 0.74 (0.67, 0.82). The bias (mean error) was -0.25 mmHg; however, the Bland-Altman limits where 95% of individual pressure differences are

  13. CSF Markers in Guillain-Barre Syndrome

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2007-01-01

    Full Text Available A positive 14-3-3 protein assay of CSF was observed in 29 of 38 patients with GBS and in 4 with motor neuron disease and other neuropathies studied at Universities of Milan and Verona, Italy.

  14. Confirmed viral meningitis with normal CSF findings.

    Science.gov (United States)

    Dawood, Naghum; Desjobert, Edouard; Lumley, Janine; Webster, Daniel; Jacobs, Michael

    2014-07-17

    An 18-year-old woman presented with a progressively worsening headache, photophobia feverishness and vomiting. Three weeks previously she had returned to the UK from a trip to Peru. At presentation, she had clinical signs of meningism. On admission, blood tests showed a mild lymphopenia, with a normal C reactive protein and white cell count. Chest X-ray and CT of the head were normal. Cerebrospinal fluid (CSF) microscopy was normal. CSF protein and glucose were in the normal range. MRI of the head and cerebral angiography were also normal. Subsequent molecular testing of CSF detected enterovirus RNA by reverse transcriptase PCR. The patient's clinical syndrome correlated with her virological diagnosis and no other cause of her symptoms was found. Her symptoms were self-limiting and improved with supportive management. This case illustrates an important example of viral central nervous system infection presenting clinically as meningitis but with normal CSF microscopy.

  15. Impact of antihypertensive combination and monotreatments on blood pressure variability: assessment by old and new indices. Data from a large ambulatory blood pressure monitoring database.

    LENUS (Irish Health Repository)

    Parati, Gianfranco

    2014-06-01

    High 24-h ambulatory blood pressure (ABP) variability is associated with poor cardiovascular outcomes. We analysed a large ABP monitoring database containing data from hypertensive patients treated with telmisartan\\/amlodipine combination or various monotherapies with the aim of quantifying the 24-h distribution of blood pressure (BP) reduction by treatment through the smoothness index and of developing and testing a new treatment-on-variability index (TOVI) to quantify the effects of treatment on both mean BP and BP variability.

  16. Wearable Sensing of In-Ear Pressure for Heart Rate Monitoring with a Piezoelectric Sensor

    Directory of Open Access Journals (Sweden)

    Jang-Ho Park

    2015-09-01

    Full Text Available In this study, we developed a novel heart rate (HR monitoring approach in which we measure the pressure variance of the surface of the ear canal. A scissor-shaped apparatus equipped with a piezoelectric film sensor and a hardware circuit module was designed for high wearability and to obtain stable measurement. In the proposed device, the film sensor converts in-ear pulse waves (EPW into electrical current, and the circuit module enhances the EPW and suppresses noise. A real-time algorithm embedded in the circuit module performs morphological conversions to make the EPW more distinct and knowledge-based rules are used to detect EPW peaks. In a clinical experiment conducted using a reference electrocardiogram (ECG device, EPW and ECG were concurrently recorded from 58 healthy subjects. The EPW intervals between successive peaks and their corresponding ECG intervals were then compared to each other. Promising results were obtained from the samples, specifically, a sensitivity of 97.25%, positive predictive value of 97.17%, and mean absolute difference of 0.62. Thus, highly accurate HR was obtained from in-ear pressure variance. Consequently, we believe that our proposed approach could be used to monitor vital signs and also utilized in diverse applications in the near future.

  17. Wearable Sensing of In-Ear Pressure for Heart Rate Monitoring with a Piezoelectric Sensor.

    Science.gov (United States)

    Park, Jang-Ho; Jang, Dae-Geun; Park, Jung Wook; Youm, Se-Kyoung

    2015-09-16

    In this study, we developed a novel heart rate (HR) monitoring approach in which we measure the pressure variance of the surface of the ear canal. A scissor-shaped apparatus equipped with a piezoelectric film sensor and a hardware circuit module was designed for high wearability and to obtain stable measurement. In the proposed device, the film sensor converts in-ear pulse waves (EPW) into electrical current, and the circuit module enhances the EPW and suppresses noise. A real-time algorithm embedded in the circuit module performs morphological conversions to make the EPW more distinct and knowledge-based rules are used to detect EPW peaks. In a clinical experiment conducted using a reference electrocardiogram (ECG) device, EPW and ECG were concurrently recorded from 58 healthy subjects. The EPW intervals between successive peaks and their corresponding ECG intervals were then compared to each other. Promising results were obtained from the samples, specifically, a sensitivity of 97.25%, positive predictive value of 97.17%, and mean absolute difference of 0.62. Thus, highly accurate HR was obtained from in-ear pressure variance. Consequently, we believe that our proposed approach could be used to monitor vital signs and also utilized in diverse applications in the near future.

  18. Ambulatory blood pressure monitoring and structural changes in carotid arteries in normotensive workers occupationally exposed to lead.

    Science.gov (United States)

    Poreba, Rafał; Poreba, Małgorzata; Gać, Paweł; Andrzejak, Ryszard

    2011-09-01

    Occupational exposure to lead may cause an increase in blood pressure. The aim of the study was to estimate the effect of occupational exposure to lead on selected parameters of ambulatory blood pressure monitoring (ABPM) and structural changes in carotid arteries. The study included 33 normotensive men occupationally exposed to lead and 39 unexposed men employed in administration of the foundry. All of the men underwent 24-hour ambulatory blood pressure monitoring and high-resolution B-mode ultrasonography to determine intima-media thickness (IMT). The group of men occupationally exposed to lead manifested significantly higher mean systolic blood pressure (MSBP), mean diastolic blood pressure (MDBP), mean blood pressure (MBP), pulse pressure (PP), variability of diastolic blood pressure (VDBP), and IMT than the unexposed group. The studied groups did not differ in mean values of variability of systolic blood pressure (VSBP). As compared to the unexposed group, in men exposed to lead, atherosclerotic plaques were significantly more common. In the group of persons exposed to lead the Pearson's correlation coefficient analysis revealed significant linear positive correlations between MSBP and IMT, between lead level and the number of atherosclerotic plaques, and between lead level and PP. Multivariate stepwise regression analysis demonstrated that higher lead level in blood and higher triglyceride concentration in blood represent independent risk factors of an increased pulse pressure in the group of individuals occupationally exposed to lead. Occupational exposure to lead can be associated with increased blood pressure and accelerated progression of atherosclerosis.

  19. Effects of environmental parameters and irrigation on the turgor pressure of banana plants measured using the non-invasive, online monitoring leaf patch clamp pressure probe.

    Science.gov (United States)

    Zimmermann, U; Rüger, S; Shapira, O; Westhoff, M; Wegner, L H; Reuss, R; Gessner, P; Zimmermann, G; Israeli, Y; Zhou, A; Schwartz, A; Bamberg, E; Zimmermann, D

    2010-05-01

    Turgor pressure provides a sensitive indicator for irrigation scheduling. Leaf turgor pressure of Musa acuminate was measured by using the so-called leaf patch clamp pressure probe, i.e. by application of an external, magnetically generated and constantly retained clamp pressure to a leaf patch and determination of the attenuated output pressure P(p) that is highly correlated with the turgor pressure. Real-time recording of P(p) values was made using wireless telemetric transmitters, which send the data to a receiver base station where data are logged and transferred to a GPRS modem linked to an Internet server. Probes functioned over several months under field and laboratory conditions without damage to the leaf patch. Measurements showed that the magnetic-based probe could monitor very sensitively changes in turgor pressure induced by changes in microclimate (temperature, relative humidity, irradiation and wind) and irrigation. Irrigation effects could clearly be distinguished from environmental effects. Interestingly, oscillations in stomatal aperture, which occurred frequently below turgor pressures of 100 kPa towards noon at high transpiration or at high wind speed, were reflected in the P(p) values. The period of pressure oscillations was comparable with the period of oscillations in transpiration and photosynthesis. Multiple probe readings on individual leaves and/or on several leaves over the entire height of the plants further emphasised the great impact of this non-invasive turgor pressure sensor system for elucidating the dynamics of short- and long-distance water transport in higher plants.

  20. Multipoint Pressure and Temperature Sensing Fiber Optic Cable for Monitoring CO2 Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Challener, William

    2014-12-31

    This report describes the work completed on contract DE-FE0010116. The goal of this two year project was to develop and demonstrate in the laboratory a highly accurate multi-point pressure measurement fiber optic cable based on MEMS pressure sensors suitable for downhole deployment in a CO2 sequestration well. The sensor interrogator was also to be demonstrated in a remote monitoring system and environmental testing was to be completed to indicate its downhole survivability over a lengthy period of time (e.g., 20 years). An interrogator system based on a pulsed laser excitation was shown to be capable of multiple (potentially 100+) simultaneous sensor measurements. Two sensors packages were completed and spliced in a cable onto the same fiber and measured. One sensor package was subsequently measured at high temperatures and pressures in supercritical CO2, while the other package was measured prior and after being subjected to high torque stresses to mimic downhole deployment. The environmental and stress tests indicated areas in which the package design should be further improved.

  1. [Ambulatory blood pressure monitoring is a useful tool for all patients].

    Science.gov (United States)

    de la Sierra, A

    Clinical blood pressure measurement (BP) is an occasional and imperfect way of estimating this biological variable. Ambulatory blood pressure monitoring (ABPM) is by far the best clinical tool for measuring an individual's blood pressure. Mean values over 24h, through the daytime and at night all make it more possible to predict organic damage and the future development of the disorder. ABPM enables the detection of white-coat hypertension and masked hypertension in both the diagnosis and follow-up of treated patients. Although some of the advantages of ABPM can be reproduced by more automated measurement without the presence of an observer in the clinic or self-measurement at home, there are some other elements of great interest that are unique to ABPM, such as seeing what happens to a patient's BP at night, the night time dipping pattern and short-term variability, all of which relate equally to the patient's prognosis. There is no scientific or clinical justification for denying these advantages, and ABPM should form part of the evaluation and follow-up of practically all hypertensive patients. Rather than continuing unhelpful discussions as to its availability and acceptability, we should concentrate our efforts on ensuring its universal availability and clearly explaining its advantages to both doctors and patients. Copyright © 2016 SEH-LELHA. Publicado por Elsevier España, S.L.U. All rights reserved.

  2. Ambulatory blood pressure monitoring in patients with hyperthyroidism before and after control of thyroid function.

    Science.gov (United States)

    Iglesias, P; Acosta, M; Sánchez, R; Fernández-Reyes, M J; Mon, C; Díez, J J

    2005-07-01

    Thyroid hormones have pronounced effects on the cardiovascular system. Thyrotoxicosis affects blood pressure (BP), modifying both diastolic (DBP) and systolic (SBP) pressures. There are no studies examining BP with ambulatory blood pressure monitoring (ABPM) in hyperthyroidism before and after control of thyroid function. Our aims were (1) to analyse ABPM in a group of normotensive hyperthyroid patients before and after normalizing circulating thyroid hormones and (2) to compare these results with those obtained in a group of euthyroid subjects. We studied 20 normotensive hyperthyroid subjects [18 women; age (mean +/- SEM) 49.0 +/- 3.0 years] and 15 healthy subjects. Patients were evaluated by ABPM over 24 h, at diagnosis and after therapy (n = 18). The average 24-h, daytime and night-time SBP was significantly greater in hyperthyroid patients than in controls with no significant differences in DBP. Circadian BP rhythm, estimated by the difference between mean values of SBP, DBP and mean BP during daytime and night-time, was unchanged. The average 24-h and daytime SBP significantly decreased after normalizing thyroid function in the 18 hyperthyroid evaluated patients. Daytime SBP and DBP were higher than night-time values both before and after control of thyroid function. However, no differences in circadian BP rhythm were observed. Normotensive hyperthyroid patients exhibit higher ambulatory SBP throughout 24 h than normotensive euthyroid subjects. Control of hyperthyroidism decreases ambulatory SBP values. Mean nocturnal fall in BP is comparable in normotensive hyperthyroid patients and control subjects.

  3. Multipoint Pressure and Temperature Sensing Fiber Optic Cable for Monitoring CO2 Sequestration

    Energy Technology Data Exchange (ETDEWEB)

    Challener, William [General Electric Company, Niskayuna, NY (United States)

    2015-02-10

    This report describes the work completed on contract DE-FE0010116. The goal of this two year project was to develop and demonstrate in the laboratory a highly accurate multi-point pressure measurement fiber optic cable based on MEMS pressure sensors suitable for downhole deployment in a CO2 sequestration well. The sensor interrogator was also to be demonstrated in a remote monitoring system and environmental testing was to be completed to indicate its downhole survivability over a lengthy period of time (e.g., 20 years). An interrogator system based on a pulsed laser excitation was shown to be capable of multiple (potentially 100+) simultaneous sensor measurements. Two sensors packages were completed and spliced in a cable onto the same fiber and measured. One sensor package was subsequently measured at high temperatures and pressures in supercritical CO2, while the other package was measured prior and after being subjected to high torque stresses to mimic downhole deployment. The environmental and stress tests indicated areas in which the package design should be further improved.

  4. Sleep Monitoring Based on a Tri-Axial Accelerometer and a Pressure Sensor.

    Science.gov (United States)

    Nam, Yunyoung; Kim, Yeesock; Lee, Jinseok

    2016-05-23

    Sleep disorders are a common affliction for many people even though sleep is one of the most important factors in maintaining good physiological and emotional health. Numerous researchers have proposed various approaches to monitor sleep, such as polysomnography and actigraphy. However, such approaches are costly and often require overnight treatment in clinics. With this in mind, the research presented here has emerged from the question: "Can data be easily collected and analyzed without causing discomfort to patients?" Therefore, the aim of this study is to provide a novel monitoring system for quantifying sleep quality. The data acquisition system is equipped with multimodal sensors, including a three-axis accelerometer and a pressure sensor. To identify sleep quality based on measured data, a novel algorithm, which uses numerous physiological parameters, was proposed. Such parameters include non-REM sleep time, the number of apneic episodes, and sleep durations for dominant poses. To assess the effectiveness of the proposed system, three participants were enrolled in this experimental study for a duration of 20 days. From the experimental results, it can be seen that the proposed monitoring system is effective for quantifying sleep quality.

  5. Limitations of stroke volume estimation by non-invasive blood pressure monitoring in hypergravity.

    Directory of Open Access Journals (Sweden)

    Olivier Manen

    Full Text Available Altitude and gravity changes during aeromedical evacuations induce exacerbated cardiovascular responses in unstable patients. Non-invasive cardiac output monitoring is difficult to perform in this environment with limited access to the patient. We evaluated the feasibility and accuracy of stroke volume estimation by finger photoplethysmography (SVp in hypergravity.Finger arterial blood pressure (ABP waveforms were recorded continuously in ten healthy subjects before, during and after exposure to +Gz accelerations in a human centrifuge. The protocol consisted of a 2-min and 8-min exposure up to +4 Gz. SVp was computed from ABP using Liljestrand, systolic area, and Windkessel algorithms, and compared with reference values measured by echocardiography (SVe before and after the centrifuge runs.The ABP signal could be used in 83.3% of cases. After calibration with echocardiography, SVp changes did not differ from SVe and values were linearly correlated (p<0.001. The three algorithms gave comparable SVp. Reproducibility between SVp and SVe was the best with the systolic area algorithm (limits of agreement -20.5 and +38.3 ml.Non-invasive ABP photoplethysmographic monitoring is an interesting technique to estimate relative stroke volume changes in moderate and sustained hypergravity. This method may aid physicians for aeronautic patient monitoring.

  6. Re-evaluation of Pre-pump Arterial Pressure to Avoid Inadequate Dialysis and Hemolysis: Importance of Prepump Arterial Pressure Monitoring in Hemodialysis Patients.

    Science.gov (United States)

    Shibata, Eriko; Nagai, Kojiro; Takeuchi, Risa; Noda, Yasuhiro; Makino, Tomomi; Chikata, Yusuke; Hann, Michael; Yoshimoto, Sakiya; Ono, Hiroyuki; Ueda, Sayo; Tamaki, Masanori; Murakami, Taichi; Matsuura, Motokazu; Abe, Hideharu; Doi, Toshio

    2015-07-01

    Prepump arterial pressure (PreAP) is monitored to avoid generating excessive negative pressure. The National Kidney Foundation K/DOQI clinical practice guidelines for vascular access recommend that PreAP should not fall below -250 mm Hg because excessive negative PreAP can lead to a decrease in the delivery of blood flow, inadequate dialysis, and hemolysis. Nonetheless, these recommendations are consistently disregarded in clinical practice and pressure sensors are often removed from the dialysis circuit. Thus far, delivered blood flow has been reported to decrease at values more negative than -150 mm Hg of PreAP. These values have been analyzed by an ultrasonic flowmeter and not directly measured. Furthermore, no known group has evaluated whether PreAP-induced hemolysis occurs at a particular threshold. Therefore, the aim of this study was to clarify the importance of PreAP in the prediction of inadequate dialysis and hemolysis. By using different diameter needles, human blood samples from healthy volunteers were circulated in a closed dialysis circuit. The relationship between PreAP and delivered blood flow or PreAP and hemolysis was investigated. We also investigated the optimal value for PreAP using several empirical monitoring methods, such as a pressure pillow. Our investigation indicated that PreAP is a critical factor in the determination of delivered blood flow and hemolysis, both of which occured at pressure values more negative than -150 mm Hg. With the exception of direct pressure monitoring, commonly used monitoring methods for PreAP were determined to be ineffective. We propose that the use of a vacuum monitor would permit regular measurement of PreAP. Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

  7. Elevation of MMP-3 and MMP-9 in CSF and Blood in Patients with Severe Traumatic Brain Injury

    Science.gov (United States)

    Grossetete, Mark; Phelps, Jeremy; Arko, Leopold; Yonas, Howard; Rosenberg, Gary A.

    2009-01-01

    OBJECTIVE Traumatic brain injury (TBI) causes elevation of matrix metalloproteinases (MMPs), which are associated with neuroinflammation, blood-brain barrier (BBB) disruption, hemorrhage and cell death. We hypothesized that patients with TBI have an increase in MMPs in the ventricular cerebrospinal fluid (CSF) and plasma. METHODS Patients with TBI and a ventricular catheter were entered into the study. Samples of CSF and plasma were collected at the time of catheter placement, and 24 and 72 hrs after admission. Seven TBI patients were entered into the study with six having complete data for analysis. Only patients that had a known time of insult that fell within a six hour window from initial insult to ventriculostomy were accepted into the study. Control CSF came from ventricular fluid in patients undergoing shunt placement for normal pressure hydrocephalus (NPH). Both MMP-2 and MMP-9 were measured with gelatin zymography and MMP-3 with Western immunoblotting. RESULTS We found a significant elevation in the levels of the latent form of MMP-9 (92-kDa) in the CSF obtained at the time of arrival (TOA) (p<0.05). Elevated levels of MMP-2 were detected in plasma at 72 hours, but not in the CSF. Using albumin from both CSF and blood, we calculated the MMP-9 index, which was significantly elevated in the CSF, indicating endogenous MMP production. Western immunoblots showed increased levels of MMP-3 in CSF at all times measured, while MMP-3 was not detected in the CSF of NPH. CONCLUSIONS We show that MMPs are elevated in CSF of TBI patients. Although the number of patients was small, the results were robust and clearly demonstrated elevations of MMP-3 and MMP-9 in ventricular CSF in TBI patients compared to controls. While these preliminary results will need to be replicated, we propose that MMPs may be important in BBB opening and hemorrhage secondary to brain injury in patients. PMID:19834375

  8. A wireless monitoring system for Hydrocephalus shunts.

    Science.gov (United States)

    Narayanaswamy, A; Nourani, M; Tamil, L; Bianco, S

    2015-08-01

    Patients with Hydrocephalus are usually treated by diverting the excess Cerebrospinal Fluid (CSF) to other parts of the body using shunts. More than 40 percentage of shunts implanted fail within the first two years. Obstruction in the shunts is one of the major causes of failure (45 percent) and the detection of obstruction reduces the complexity of the revision surgery. This paper describes a proposed wireless monitoring system for clog detection and flow measurement in shunts. A prototype was built using multiple pressure sensors along the shunt catheters for sensing the location of clog and flow rate. Regular monitoring of flow rates can be used to adjust the valve in the shunt to prevent over drainage or under drainage of CSF. The accuracy of the flow measurement is more than 90 percent.

  9. Monitoring of total positive end-expiratory pressure during mechanical ventilation by artificial neural networks.

    Science.gov (United States)

    Perchiazzi, Gaetano; Rylander, Christian; Pellegrini, Mariangela; Larsson, Anders; Hedenstierna, Göran

    2016-04-11

    Ventilation treatment of acute lung injury (ALI) requires the application of positive airway pressure at the end of expiration (PEEPapp) to avoid lung collapse. However, the total pressure exerted on the alveolar walls (PEEPtot) is the sum of PEEPapp and intrinsic PEEP (PEEPi), a hidden component. To measure PEEPtot, ventilation must be discontinued with an end-expiratory hold maneuver (EEHM). We hypothesized that artificial neural networks (ANN) could estimate the PEEPtot from flow and pressure tracings during ongoing mechanical ventilation. Ten pigs were mechanically ventilated, and the time constant of their respiratory system (τRS) was measured. We shortened their expiratory time (TE) according to multiples of τRS, obtaining different respiratory patterns (Rpat). Pressure (PAW) and flow (V'AW) at the airway opening during ongoing mechanical ventilation were simultaneously recorded, with and without the addition of external resistance. The last breath of each Rpat included an EEHM, which was used to compute the reference PEEPtot. The entire protocol was repeated after the induction of ALI with i.v. injection of oleic acid, and 382 tracings were obtained. The ANN had to extract the PEEPtot, from the tracings without an EEHM. ANN agreement with reference PEEPtot was assessed with the Bland-Altman method. Bland Altman analysis of estimation error by ANN showed -0.40 ± 2.84 (expressed as bias ± precision) and ±5.58 as limits of agreement (data expressed as cmH2O). The ANNs estimated the PEEPtot well at different levels of PEEPapp under dynamic conditions, opening up new possibilities in monitoring PEEPi in critically ill patients who require ventilator treatment.

  10. Unconstrained pulse pressure monitoring for health management using hetero-core fiber optic sensor.

    Science.gov (United States)

    Nishiyama, Michiko; Sonobe, Masako; Watanabe, Kazuhiro

    2016-09-01

    In this paper, we present a pulse pressure waveform sensor that does not constrain a wearer's daily activity; the sensor uses hetero-core fiber optics. Hetero-core fiber sensors have been found to be sensitive to moderate bending. To detect minute pulse pressure changes from the radial artery at the wrist, we devised a fiber sensor arrangement using three-point bending supports. We analyzed and evaluated the measurement validity using wavelet transformation, which is well-suited for biological signal processing. It was confirmed that the detected pulse waveform had a fundamental mode frequency of around 1.25 Hz over the time-varying waveform. A band-pass filter with a range of frequencies from 0.85 to 1.7 Hz was used to pick up the fundamental mode. In addition, a high-pass filter with 0.85 Hz frequency eliminated arm motion artifacts; consequently, we achieved high signal-to-noise ratio. For unrestricted daily health management, it is desirable that pulse pressure monitoring can be achieved by simply placing a device on the hand without the sensor being noticed. Two types of arrangements were developed and demonstrated in which the pulse sensors were either embedded in a base, such as an armrest, or in a wearable device. A wearable device without cuff pressure using a sensitivity-enhanced fiber sensor was successfully achieved with a sensitivity of 0.07-0.3 dB with a noise floor lower than 0.01 dB for multiple subjects.

  11. Proximal Limb Weakness Reverting After CSF Diversion In Intracranial Hypertension

    Directory of Open Access Journals (Sweden)

    Sinha S

    2005-01-01

    Full Text Available We report about two young girls who developed progressive visual failure secondary to increased intracranial pressure and had significant proximal muscle weakness of limbs. Patients with elevated intracranial pressure (ICP may present with "false localizing signs", besides having headache, vomiting and papilledema. Radicular pain as a manifestation of raised ICP is rare and motor weakness attributable to polyradiculopathy is exceptional. Two patients with increased intracranial pressure without lateralizing signs′ had singnificant muscle weakness. Clinical evaluation and laboratory tests did not disclose any other cause for weakness. Following theco-peritoneal shunt, in both patients, there was variable recovery of vision but the proximal weakness and symptoms of elevated ICP improved rapidly. Recognition of this uncommon manifestation of raised ICP may obviate the need for unnecessary investigation and reduce morbidity due to weakness by CSF diversion procedure.

  12. Intraocular Pressure Fluctuations and 24-Hour Continuous Monitoring for Glaucoma Risk in Wind Instrument Players.

    Science.gov (United States)

    de Crom, Ronald M P C; Webers, Carroll A B; van Kooten-Noordzij, Marina A W; Michiels, Agnes C; Schouten, Jan S A G; Berendschot, Tos T J M; Beckers, Henny J M

    2017-08-30

    The purpose of this study is to investigate the influence of playing a wind instrument on intraocular pressure (IOP) and to monitor 24-hour (IOP) fluctuations in wind musicians of symphony and wind orchestras to compare IOP levels during normal daily activities with IOP levels during playing. Professional and amateur musicians of symphony and wind orchestras were invited to participate. A total of 42 participants, 9 with glaucoma, underwent a routine ophthalmologic examination. IOP measurements were taken before and immediately after 20 minutes of playing wind instruments. In addition, 6 participants underwent 24-hour IOP monitoring with the Triggerfish (Sensimed AG, Switzerland) sensing contact lens, during which they kept an activity logbook. Eleven professionals and 31 amateur musicians participated in the study. A total of 7 eyes of 6 patients underwent additional 24-hour IOP monitoring. Mean IOP before playing was 13.6±2.6 mm Hg, IOP change after playing was +1.5±2.2 mm Hg with a significant difference between professionals (2.5±1.5 mm Hg) and amateurs (1.1±2.3 mm Hg). There were no significant differences in IOP change between subjects with or without glaucoma. During 24-hour IOP monitoring there were slight increases in IOP while playing an instrument, but also during other activities and overnight. These latter IOP levels were similar or even higher than the IOP rise caused by playing a wind instrument. IOP often rises after playing wind instruments, but similar or even higher IOP levels seem to occur during common other daily activities or at night. These peaks may be relevant for glaucomatous field progression and treatment of glaucoma patients.

  13. Analysis of novel geometry-independent method for dialysis access pressure-flow monitoring

    Directory of Open Access Journals (Sweden)

    Panduranga Harsha

    2008-11-01

    Full Text Available Abstract Background End-stage renal disease (ESRD confers a large health-care burden for the United States, and the morbidity associated with vascular access failure has stimulated research into detection of vascular access stenosis and low flow prior to thrombosis. We present data investigating the possibility of using differential pressure (ΔP monitoring to estimate access flow (Q for dialysis access monitoring, with the goal of utilizing micro-electro-mechanical systems (MEMS pressure sensors integrated within the shaft of dialysis needles. Methods A model of the arteriovenous graft fluid circuit was used to study the relationship between Q and the ΔP between two dialysis needles placed 2.5–20.0 cm apart. Tubing was varied to simulate grafts with inner diameters of 4.76–7.95 mm. Data were compared with values from two steady-flow models. These results, and those from computational fluid dynamics (CFD modeling of ΔP as a function of needle position, were used to devise and test a method of estimating Q using ΔP and variable dialysis pump speeds (variable flow that diminishes dependence on geometric factors and fluid characteristics. Results In the fluid circuit model, ΔP increased with increasing volume flow rate and with increasing needle-separation distance. A nonlinear model closely predicts this ΔP-Q relationship (R2 > 0.98 for all graft diameters and needle-separation distances tested. CFD modeling suggested turbulent needle effects are greatest within 1 cm of the needle tip. Utilizing linear, quadratic and combined variable flow algorithms, dialysis access flow was estimated using geometry-independent models and an experimental dialysis system with the pressure sensors separated from the dialysis needle tip by distances ranging from 1 to 5 cm. Real-time ΔP waveform data were also observed during the mock dialysis treatment, which may be useful in detecting low or reversed flow within the access. Conclusion With further

  14. Can ambulatory blood-pressure monitoring provide reliable indices of arterial stiffness?

    Science.gov (United States)

    Gosse, Philippe; Papaioanou, Georgios; Coulon, Paul; Reuter, Sylvain; Lemetayer, Philippe; Safar, Michel

    2007-08-01

    The use of ambulatory recordings of blood pressure (BP) was proposed to estimate arterial stiffness (AS). We compared the relative value of the ambulatory AS index (AASI), and of the slope of pulse pressure (PP) according to mean BP (MBP) obtained from 24-h ambulatory BP monitoring, to the monitoring of the arrival time of Korotkoff sounds (QKD interval) in the prediction of cardiovascular (CV) events. Twenty-four-hour ambulatory BP and QKD monitoring were recorded at baseline, before antihypertensive treatment of hypertensive patients in our Bordeaux cohort. From these recordings, the AASI, the PP/MBP slope, and the theoretical value of the QKD for a systolic pressure of 100 mm Hg and a heart rate of 60 beats/min (QKD100-60) were calculated. The patients were then given antihypertensive treatment and followed by their family physicians, who were unaware of the QKD, AASI, and PP/MBP slope results. Regular updates on patients were obtained. The reproducibility of measurements was studied in 38 normal subjects evaluated on two occasions. The reproducibility of the AASI and the PP/MBP slope was less than that of BP over 24 h and of QKD100-60. The cohort comprised 469 patients. With an average follow-up of 70+/-39 months, 62 CV complications, including 13 deaths, were recorded. In the monovariate analysis, age, PP over 24 h, QKD100-60, AASI, and the PP/MBP slope were significantly related to the occurrence of complications. In the multivariate analysis, when age and PP over 24 were included in the model, only QKD100-60 remained significantly linked to CV events. Our data support the value of the AASI as an indirect estimate of AS and as an element in the evaluation of CV risk in hypertensive patients. However, the reproducibility of this index is less, and its predictive value for complications is poorer, than that of QKD100-60, a parameter that we believe is more closely linked to AS.

  15. Application of Ambulatory Blood Pressure Monitoring Essential Hypertension with Target-Organ Damage

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    @@The purpose of this study was to determine whether this normal ambulatory blood pressure (ABP) criterion deter-mined by JVC-VI was suitable for Chinese patients with es-sential hypertention (EH), in order to decrease target organ damage (TOD). 24-hour ABP monitoring (ABPM) results in 1 325 cases with reliable data according with the selected criteria were investigated. 106 normotensives (65 men, 41women, mean age 52 years), 498 untreated simple hyper-tensives (288 men, 210 women, mean age 54 years) and 722 recently untreated hypertensives with TOD (490 men,232 women, mean age 58 years) including 53% cardiac damage, 16% cerebral damage, 9% renal damage and 22 % more than one organ damage were studied.

  16. Blood Pressure Deviations From Optimal Mean Arterial Pressure During Cardiac Surgery Measured With a Novel Monitor of Cerebral Blood Flow and Risk for Perioperative Delirium: A Pilot Study.

    Science.gov (United States)

    Hori, Daijiro; Max, Laura; Laflam, Andrew; Brown, Charles; Neufeld, Karin J; Adachi, Hideo; Sciortino, Christopher; Conte, John V; Cameron, Duke E; Hogue, Charles W; Mandal, Kaushik

    2016-06-01

    The aim of this study was to evaluate whether excursions of blood pressure from the optimal mean arterial pressure during and after cardiac surgery are associated with postoperative delirium identified using a structured examination. Prospective, observational study. University hospital. The study included 110 patients undergoing cardiac surgery. Patients were monitored using ultrasound-tagged near-infrared spectroscopy to assess optimal mean arterial pressure by cerebral blood flow autoregulation monitoring during cardiopulmonary bypass and the first 3 hours in the intensive care unit. The patients were tested preoperatively and on postoperative days 1 to 3 with the Confusion Assessment Method or Confusion Assessment Method for the Intensive Care Unit, the Delirium Rating Scale-Revised-98, and the Mini Mental State Examination. Summative presence of delirium on postoperative days 1 through 3, as defined by the consensus panel following Diagnostic and Statistical Manual of Mental Disorders-IV-TR criteria, was the primary outcome. Delirium occurred in 47 (42.7%) patients. There were no differences in blood pressure excursions above and below optimal mean arterial pressure between patients with and without summative presence of delirium. Secondary analysis showed blood pressure excursions above the optimal mean arterial pressure to be higher in patients with delirium (mean±SD, 33.2±26.51 mmHgxh v 23.4±16.13 mmHgxh; p = 0.031) and positively correlated with the Delirium Rating Scale score on postoperative day 2 (r = 0.27, p = 0.011). Summative presence of delirium was not associated with perioperative blood pressure excursions; but on secondary exploratory analysis, excursions above the optimal mean arterial pressure were associated with the incidence and severity of delirium on postoperative day 2. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Peripheral arterial blood pressure versus central crterial blood pressure monitoring in critically ill patients after Cardio-pulmonary Bypass.

    Science.gov (United States)

    Ahmad, Rana Altaf; Ahmad, Suhail; Naveed, Anjum; Baig, Mirza Ahmad Raza

    2017-01-01

    To determine the accuracy of peripheral (radial) arterial access as compared to central (femoral) arterial access for measurement of invasive blood pressure (IBP) in critically ill patients after cardiopulmonary bypass. Sixty patients (60) who required high inotropic/vasopressor support on weaning from cardio-pulmonary bypass and weaned off in 2(nd) attempt were included in this study. The duration of this study was from June 2015 to August 2016. Radial and femoral arterial access was achieved in all patients for simultaneous measurement of blood pressure. Arterial pressures were noted after 5, 15 and 30 minutes of weaning from cardiopulmonary bypass for both radial and femoral artery simultaneously. Mean age of study patients was 56.48±11.17 years. 85% patients were male. There was significant difference in systolic blood pressure, diastolic blood pressure and mean arterial pressures between the radial artery and femoral artery cannulation. Mean arterial pressures were significantly high in femoral artery as compared to the radial artery. The mean arterial pressures after five minutes of weaning using central access were 76.28±10.21 mmHg versus 64.15±6.76 mmHg in peripheral arterial access (p-value arterial pressures after 15 minutes of weaning from cardiopulmonary bypass 78.70±10.12 mmHg in central access versus 72.03±6.76 mmHg using peripheral arterial access (p-value arterial pressures were less marked as compared to the previous differences after 30 minutes of weaning from cardiopulmonary bypass as compared to the earlier readings (p-value 0.001). Peripheral arterial pressures are unreliable in critically ill patients after cardiopulmonary bypass receiving high dose of inotropic drugs. Central arterial access should be used in these patients to get accurate estimates of patients' blood pressure in early periods after cardiopulmonary bypass.

  18. Validity and reliability of a pressure ulcer monitoring tool for persons with spinal cord impairment.

    Science.gov (United States)

    Thomason, Susan S; Luther, Stephen L; Powell-Cope, Gail M; Harrow, Jeffrey J; Palacios, Polly

    2014-05-01

    The purpose was to provide support for validity and reliability of the spinal cord impairment pressure ulcer monitoring tool (SCI-PUMT) to assess pressure ulcer (PrU) healing. Expert panels developed a 30-item pool, including new items and items from two established PrU healing tools, to represent potential variables for monitoring PrU healing. Subjects were prospectively assessed weekly for each variable over a 12-week period. Data collection was conducted on a cohort of inpatients and outpatients in one Spinal Cord Injury/Disorders Center in the Veterans' Health Administration. A convenience sample of Veterans (n = 66) with spinal cord impairment (SCI) was recruited. Eligible subjects had at least one PrU (n = 167) and a history of SCI for longer than 1 year. Interventions Not applicable. A change in PrU volume was calculated using VeV Measurement Documentation software and a digital imaging camera. Content validity was established for a pool of items designed to gauge PrU healing. Exploratory factor analysis (construct validity) identified a parsimonious set of seven items for inclusion in the SCI-PUMT to assess PrU healing. The SCI-PUMT was found to explain 59% of the variance of the volume across the study. Inter-rater reliability was 0.79 and intra-rater reliability ranged from 0.81 to 0.99 among research assistants. Similar levels of reliability were subsequently established among registered nurses, who used the SCI-PUMT in the clinical setting. The final version of the SCI-PUMT was determined to be valid, reliable, and sensitive in detecting PrU healing over time in Veterans with SCI.

  19. BION-M 1: First continuous blood pressure monitoring in mice during a 30-day spaceflight

    Science.gov (United States)

    Andreev-Andrievskiy, Alexander; Popova, Anfisa; Lloret, Jean-Christophe; Aubry, Patrick; Borovik, Anatoliy; Tsvirkun, Daria; Vinogradova, Olga; Ilyin, Eugeniy; Gauquelin-Koch, Guillemette; Gharib, Claude; Custaud, Marc-Antoine

    2017-05-01

    Animals are an essential component of space exploration and have been used to demonstrate that weightlessness does not disrupt essential physiological functions. They can also contribute to space research as models of weightlessness-induced changes in humans. Animal research was an integral component of the 30-day automated Russian biosatellite Bion-M 1 space mission. The aim of the hemodynamic experiment was to estimate cardiovascular function in mice, a species roughly 3000 times smaller than humans, during prolonged spaceflight and post-flight recovery, particularly, to investigate if mice display signs of cardiovascular deconditioning. For the first time, heart rate (HR) and blood pressure (BP) were continuously monitored using implantable telemetry during spaceflight and recovery. Decreased HR and unchanged BP were observed during launch, whereas both HR and BP dropped dramatically during descent. During spaceflight, BP did not change from pre-flight values. However, HR increased, particularly during periods of activity. HR remained elevated after spaceflight and was accompanied by increased levels of exercise-induced tachycardia. Loss of three of the five mice during the flight as a result of the hardware malfunction (unrelated to the telemetry system) and thus the limited sample number constitute the major limitation of the study. For the first time BP and HR were continuously monitored in mice during the 30-day spaceflight and 7-days of post-flight recovery. Cardiovascular deconditioning in these tiny quadruped mammals was reminiscent of that in humans. Therefore, the loss of hydrostatic pressure in space, which is thought to be the initiating event for human cardiovascular adaptation in microgravity, might be of less importance than other physiological mechanisms. Further experiments with larger number of mice are needed to confirm these findings.

  20. rhCSF3 accelerates the proliferation of human melanocytes in culture through binding CSF3R and the expression of CSF3R transcripts.

    Science.gov (United States)

    Lu, Yan; Guo, Ze; Zhou, Mei-Hua; Li, Xue; Sun, Jie; Gong, Qing-Li; Zhu, Wen-Yuan

    2015-05-01

    Melanogenic paracrine and autocrine cytokine networks have recently been discovered in vitro between melanocytes and other types of skin cells. Granulocyte colony-stimulating factor receptor (CSF3R) controls the survival, proliferation and differentiation of many kinds of cells, including neutrophils. To understand the function of CSF3R and recombinant human granulocyte colony-stimulating factor (rhCSF3) on melanocyte proliferation, this study compared the expression of CSF3R and the effects of rhCSF3 in primary human melanocytes, neutrophils and HEL 92.1.7 cells. The results show that CSF3R is localized in the cytoplasm and on cell membranes of melanocytes and neutrophils. The percentage of CSF3R(+) melanocytes was higher than CSF3R(+) HEL 92.1.7 cells, but was lower than CSF3R(+) neutrophils. Both CSF3R mRNA and CSF3R protein levels in melanocytes were higher than in HEL 92.1.7 cells, but were lower than in neutrophils. Treatment with rhCSF3 increased the proliferation of human melanocytes, but not their tyrosinase activity. Transcripts of CSF3R in human melanocytes, M14, A375 melanoma and A431 squamous cell carcinoma cells were also detected. Expression of the CSF3R V3 transcript was lower in melanocytes than in M14, A375 melanoma and A431 squamous cell carcinoma cells. In conclusion, rhCSF3 can promote melanocyte proliferation through CSF3R without affecting tyrosinase activity.

  1. Monitoring and Analysis of Transient Pore Water Pressures in Large Suspended Rock Slides near Poschiavo, CH

    Science.gov (United States)

    de Palézieux, Larissa; Loew, Simon; Zwahlen, Peter

    2016-04-01

    Many mountain slopes in the Alps exhibit large compound rock slides or Deep Seated Gravitational Slope Deformations. Due to the basal rupture plane geometry and the cumulative displacement magnitude such landslide bodies are often strongly deformed, highly fractured and - at least locally - very permeable. This can lead to high infiltration rates and low phreatic groundwater tables. This is also the situation in the studied mountain slopes southwest of Poschiavo, where large suspended rockslides occur, with very little surface runoff at high elevations, and torrents developing only at the elevation of the basal rupture planes. Below the landslide toes, at altitudes below ca. 1700 m a.s.l., groundwater appears forming spring lines or distributed spring clusters. Within the scope of the design of a hydropower pump storage plant in the Poschiavo valley by Lagobianco SA (Repower AG), numerous cored and deep boreholes (of 50 to 300 m depth) have been drilled along the planned pressure tunnel alignement at elevations ranging from 963 to 2538 m a.s.l. in the years 2010 and 2012. In several boreholes Lugeon and transient pressure tests were executed and pore water pressure sensors installed in short monitoring sections at various depths. Most of these boreholes intersect deep rockslides in crystalline rocks and limestones, showing highly fragmented rock masses and cohesionless cataclastic shear zones of several tens of meters thickness. This study explores these borehole observations in landslides and adjacent stable slopes and links them to the general hydrologic and hydrogeologic framework. The analysis of the pore water pressure data shows significant variability in seasonal trends and short-term events (from snow melt and summer rain storms) and remarkable pressure differences over short horizontal and vertical distances. This reflects rock mass damage within landslide bodies and important sealing horizons at their base. Based on water balances, the estimated effective

  2. An Implantable Cardiovascular Pressure Monitoring System with On-Chip Antenna and RF Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Yu-Chun Liu

    2015-08-01

    Full Text Available An implantable wireless system with on-chip antenna for cardiovascular pressure monitor is studied. The implantable device is operated in a batteryless manner, powered by an external radio frequency (RF power source. The received RF power level can be sensed and wirelessly transmitted along with blood pressure signal for feedback control of the external RF power. The integrated electronic system, consisting of a capacitance-to-voltage converter, an adaptive RF powering system, an RF transmitter and digital control circuitry, is simulated using a TSMC 0.18 μm CMOS technology. The implanted RF transmitter circuit is combined with a low power voltage-controlled oscillator resonating at 5.8 GHz and a power amplifier. For the design, the simulation model is setup using ADS and HFSS software. The dimension of the antenna is 1 × 0.6 × 4.8 mm3 with a 1 × 0.6 mm2 on-chip circuit which is small enough to place in human carotid artery.

  3. The Use of Ambulatory Blood Pressure Monitoring As Standard of Care in Pediatrics

    Directory of Open Access Journals (Sweden)

    Caitlin G. Peterson

    2017-06-01

    Full Text Available Hypertension (HTN is a significant global health problem, responsible for 7.5 million deaths each year worldwide. The prevalence of HTN is increasing in the pediatric population likely attributed to the increase in childhood obesity. Recent work has also shown that blood pressure (BP tends to track from childhood to adulthood including BP-related target organ damage. In the last 25–30 years, pediatric use of ambulatory blood pressure monitoring (ABPM has been expanding mainly in the setting of initial elevated BP measurement evaluation, HTN therapy efficacy follow-up, and renal disease. However, there are many clinical areas where ABPM could potentially be used but is currently underutilized. This review summarizes the current knowledge and the uses of pediatric ABPM and explores clinical areas where it can be very useful both to detect HTN and its longitudinal follow-up. And thus, ABPM could serve as a critical tool to potentially prevent early cardiovascular mortality and morbidity in wide variety of populations. With solid data to support ABPM’s superiority over clinic BP measurements and these clinical areas for its expansion, ABPM should now be part of standard of care in BP evaluation and management in pediatrics.

  4. Monitoring Composite Material Pressure Vessels with a Fiber-Optic/Microelectronic Sensor System

    Science.gov (United States)

    Klimcak, C.; Jaduszliwer, B.

    1995-01-01

    We discuss the concept of an integrated, fiber-optic/microelectronic distributed sensor system that can monitor composite material pressure vessels for Air Force space systems to provide assessments of the overall health and integrity of the vessel throughout its entire operating history from birth to end of life. The fiber optic component would include either a semiconductor light emitting diode or diode laser and a multiplexed fiber optic sensing network incorporating Bragg grating sensors capable of detecting internal temperature and strain. The microelectronic components include a power source, a pulsed laser driver, time domain data acquisition hardware, a microprocessor, a data storage device, and a communication interface. The sensing system would be incorporated within the composite during its manufacture. The microelectronic data acquisition and logging system would record the environmental conditions to which the vessel has been subjected to during its storage and transit, e.g., the history of thermal excursions, pressure loading data, the occurrence of mechanical impacts, the presence of changing internal strain due to aging, delamination, material decomposition, etc. Data would be maintained din non-volatile memory for subsequent readout through a microcomputer interface.

  5. Comparisons of Office and 24-Hour Ambulatory Blood Pressure Monitoring in Children with Obstructive Sleep Apnea.

    Science.gov (United States)

    Kang, Kun-Tai; Chiu, Shuenn-Nan; Weng, Wen-Chin; Lee, Pei-Lin; Hsu, Wei-Chung

    2017-03-01

    To compare office blood pressure (BP) and 24-hour ambulatory BP (ABP) monitoring to facilitate the diagnosis and management of hypertension in children with obstructive sleep apnea (OSA). Children aged 4-16 years with OSA-related symptoms were recruited from a tertiary referral medical center. All children underwent overnight polysomnography, office BP, and 24-hour ABP studies. Multiple linear regression analyses were applied to elucidate the association between the apnea-hypopnea index and BP. Correlation and consistency between office BP and 24-hour ABP were measured by Pearson correlation, intraclass correlation, and Bland-Altman analyses. In the 163 children enrolled (mean age, 8.2 ± 3.3 years; 67% male). The prevalence of systolic hypertension at night was significantly higher in children with moderate-to-severe OSA than in those with primary snoring (44.9% vs 16.1%, P = .006). Pearson correlation and intraclass correlation analyses revealed associations between office BP and 24-hour BP, and Bland-Altman analysis indicated an agreement between office and 24-hour BP measurements. However, multiple linear regression analyses demonstrated that 24-hour BP (nighttime systolic BP and mean arterial pressure), unlike office BP, was independently associated with the apnea-hypopnea index, after adjustment for adiposity variables. Twenty-four-hour ABP is more strongly correlated with OSA in children, compared with office BP. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. An improved flexible telemetry system to autonomously monitor sub-bandage pressure and wound moisture.

    Science.gov (United States)

    Mehmood, Nasir; Hariz, Alex; Templeton, Sue; Voelcker, Nicolas H

    2014-11-18

    This paper presents the development of an improved mobile-based telemetric dual mode sensing system to monitor pressure and moisture levels in compression bandages and dressings used for chronic wound management. The system is fabricated on a 0.2 mm thick flexible printed circuit material, and is capable of sensing pressure and moisture at two locations simultaneously within a compression bandage and wound dressing. The sensors are calibrated to sense both parameters accurately, and the data are then transmitted wirelessly to a receiver connected to a mobile device. An error-correction algorithm is developed to compensate the degradation in measurement quality due to battery power drop over time. An Android application is also implemented to automatically receive, process, and display the sensed wound parameters. The performance of the sensing system is first validated on a mannequin limb using a compression bandage and wound dressings, and then tested on a healthy volunteer to acquire real-time performance parameters. The results obtained here suggest that this dual mode sensor can perform reliably when placed on a human limb.

  7. An Improved Flexible Telemetry System to Autonomously Monitor Sub-Bandage Pressure and Wound Moisture

    Directory of Open Access Journals (Sweden)

    Nasir Mehmood

    2014-11-01

    Full Text Available This paper presents the development of an improved mobile-based telemetric dual mode sensing system to monitor pressure and moisture levels in compression bandages and dressings used for chronic wound management. The system is fabricated on a 0.2 mm thick flexible printed circuit material, and is capable of sensing pressure and moisture at two locations simultaneously within a compression bandage and wound dressing. The sensors are calibrated to sense both parameters accurately, and the data are then transmitted wirelessly to a receiver connected to a mobile device. An error-correction algorithm is developed to compensate the degradation in measurement quality due to battery power drop over time. An Android application is also implemented to automatically receive, process, and display the sensed wound parameters. The performance of the sensing system is first validated on a mannequin limb using a compression bandage and wound dressings, and then tested on a healthy volunteer to acquire real-time performance parameters. The results obtained here suggest that this dual mode sensor can perform reliably when placed on a human limb.

  8. [Arterial pressure-based cardiac output monitoring: 1. FloTrac sensor and SVV].

    Science.gov (United States)

    Seo, Katsuhiro

    2009-07-01

    FloTrac is a recently introduced semi-invasive arterial pressure-based cardiac output (APCO) monitoring device. The accuracy of a new device is usually evaluated by Bland-Altman method, which shows graphically the mean value of differences between a new method and the reference method (bias), standard deviation of the differences (precision) and limits of agreement or 2 standard deviations. Critchley et al calculated the percentage errors which are two standard deviations divided by mean cardiac output, and proposed that percentage error should be less than 30% as a reliable new method. Cardiac output was measured by FloTrac (APCO) and pulmonary arterial catheter-based thermodilution method (ICO) during off-pump coronary artery bypass and resection of pheochromocytoma, procedures associated with hemodynamically unstable conditions. As algorithm is renewed in a new version of the device, the accuracy of the device is improved; bias, precision and limits of agreement decreased; correlation coefficient increased, and percentage error was assessed to be around 30%. On the other hand, there was a tendency for increased negative bias as cardiac output increased, implying APCO tends to underestimate ICO in high CO ranges. APCO is less invasive and could rapidly respond to fast changes of hemodynamic state. FloTrac is expected to become a reliable cardiac output monitoring device even under hemodynamically unstable conditions. Further improvement of the algorithm is anticipated.

  9. Validation of non-invasive arterial pressure monitoring during carotid endarterectomy.

    Science.gov (United States)

    Heusdens, J F; Lof, S; Pennekamp, C W A; Specken-Welleweerd, J C; de Borst, G J; van Klei, W A; van Wolfswinkel, L; Immink, R V

    2016-09-01

    Patients undergoing carotid endarterectomy require strict arterial blood pressure (BP) control to maintain adequate cerebral perfusion. In this study we tested whether non-invasive beat-to-beat Nexfin finger BP (BPfin) can replace invasive beat-to-beat radial artery BP (BPrad) in this setting. In 25 consecutive patients (median age 71 yr) scheduled for carotid endarterectomy and receiving general anaesthesia, BPfin and BPrad were monitored simultaneously and ipsilaterally during the 30-min period surrounding carotid artery cross-clamping. Validation was guided by the standard set by the Association for the Advancement of Medical Instrumentation (AAMI), which considers a BP monitor adequate when bias (precision) is <5 (8) mm Hg, respectively. BPfin vs BPrad bias (precision) was -3.3 (10.8), 6.1 (5.7) and 3.5 (5.2) mm Hg for systolic, diastolic, and mean BP, respectively. One subject was excluded due to a poor quality BP curve. In another subject, mean BPfin overestimated mean BPrad by 13.5 mm Hg. Mean BPfin could be considered as an alternative for mean BPrad during a carotid endarterectomy, based on the AAMI criteria. In 23 of 24 patients, the use of mean BPfin would not lead to decisions to adjust mean BPrad values outside the predefined BP threshold. NCT01451294. © The Author 2016. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Insulin Micropump with Embedded Pressure Sensors for Failure Detection and Delivery of Accurate Monitoring

    Directory of Open Access Journals (Sweden)

    Dimitry Dumont-Fillon

    2014-11-01

    Full Text Available Improved glycemic control with insulin pump therapy in patients with type 1 diabetes mellitus has shown gradual reductions in nephropathy and retinopathy. More recently, the emerging concept of the artificial pancreas, comprising an insulin pump coupled to a continuous glucose meter and a control algorithm, would become the next major breakthrough in diabetes care. The patient safety and the efficiency of the therapy are directly derived from the delivery accuracy of rapid-acting insulin. For this purpose, a specific precision-oriented design of micropump has been built. The device, made of a stack of three silicon wafers, comprises two check valves and a pumping membrane that is actuated against stop limiters by a piezo actuator. Two membranes comprising piezoresistive strain gauges have been implemented to measure the pressure in the pumping chamber and at the outlet of the pump. Their high sensitivity makes possible the monitoring of the pumping accuracy with a tolerance of ±5% for each individual stroke of 200 nL. The capability of these sensors to monitor priming, reservoir overpressure, reservoir emptying, outlet occlusion and valve leakage has also been studied.

  11. Transatrial access for left atrial pressure (LAP) monitoring line placement in arterial switch operation (ASO) in neonates.

    Science.gov (United States)

    Akhtar, Mohammad Irfan; Hamid, Mohammad; Amanullah, Muneer; Ahsan, Khalid

    2013-11-01

    Left Atrial pressure monitoring is a useful and accurate method to guide Left ventricle filling in the patients who undergo Arterial switch operation for transposition of great arteries. We have used a different technique in three TGA patients for LA pressure monitoring line placement. After cleaning and draping,right internal jugular vein (rt IJV) located through 22G venous cannula, guide wire was put in followed by sliding the 22G x 8cm vygon arterial catheter over the guide wire into the right atrium that was directed transatrially into LA by the operating surgeon during atrial septum repair. The catheter was secured by silk on the neck and dressed with transparent dressing and was kept for a period of 48-72 hrs. LA pressure monitoring is helpful in anticipating LV dysfunction in ASO.

  12. Continuous non-invasive finger arterial pressure monitoring reflects intra-arterial pressure changes in children undergoing cardiac surgery.

    NARCIS (Netherlands)

    Hofhuizen, C.M.; Lemson, J.; Hemelaar, A.E.A.; Settels, J.J.; Schraa, O.; Singh, S.K.; Hoeven, J.G. van der; Scheffer, G.J.

    2010-01-01

    BACKGROUND: Continuous non-invasive measurement of finger arterial pressure (FAP) is a reliable technology in adults. FAP is measured with an inflatable cuff around the finger and simultaneously converted to a reconstructed brachial artery pressure waveform (reBAP) by the Nexfin device. We assessed

  13. Continuous non-invasive finger arterial pressure monitoring reflects intra-arterial pressure changes in children undergoing cardiac surgery.

    Science.gov (United States)

    Hofhuizen, C M; Lemson, J; Hemelaar, A E A; Settels, J J; Schraa, O; Singh, S K; van der Hoeven, J G; Scheffer, G J

    2010-10-01

    Continuous non-invasive measurement of finger arterial pressure (FAP) is a reliable technology in adults. FAP is measured with an inflatable cuff around the finger and simultaneously converted to a reconstructed brachial artery pressure waveform (reBAP) by the Nexfin™ device. We assessed the adequacy of a prototype device (Nexfin-paediatric), designed for a paediatric population, for detecting rapid arterial pressure changes in children during cardiac surgery. Thirteen anaesthetized children with a median age of 11 months (2 months-7 yr) undergoing congenital cardiac surgery were included in the study. reBAP and intra-arterial pressure (IAP) were recorded simultaneously during the surgical procedure. To assess the accuracy of reBAP in tracking arterial pressure changes, the four largest IAP variations within a 5 min time interval were identified from each procedure. These variations were compared offline with reBAP during a 10 s control period before and a 10 s period after an arterial pressure change had occurred. In 10 out of 13 children, a non-invasive arterial pressure recording could be obtained. Therefore, recordings from these 10 children were eligible for further analysis, resulting in 40 data points. The correlation coefficient between reBAP and IAP in tracking mean arterial pressure (MAP) changes was 0.98. reBAP followed changes in IAP with a mean bias for systolic, diastolic arterial pressure, and MAP of 0.0 mm Hg (sd 5.8), 0.1 (sd 2.8), and 0.19 (sd 2.7), respectively. The prototype device closely follows arterial pressure changes in children. However, in a considerable number of attempts, obtaining a signal was time-consuming or unsuccessful. This technique seems promising but requires further technical development.

  14. The association of serum gamma-glutamyl transpeptidase level and other laboratory parameters with blood pressure in hypertensive patients under ambulatory blood pressure monitoring

    Directory of Open Access Journals (Sweden)

    Ortakoyluoglu A

    2016-09-01

    Full Text Available Adile Ortakoyluoglu, Betul Boz, Oguzhan Sitki Dizdar, Deniz Avci, Ali Cetinkaya, Osman Baspinar Department of Internal Medicine, Kayseri Training and Research Hospital, Kayseri, Turkey Background: Hypertension is a very important cause of morbidity and mortality. Serum gamma-glutamyl transpeptidase (GGT is a biomarker of oxidative stress and associated with increased risk of hypertension and diabetes. The aim of this study was to evaluate the association of serum GGT level, which is an early marker of inflammation and endothelial dysfunction, with the deterioration of the diurnal rhythm of the blood pressure.Methods: A total of 171 patients with hypertension were included in this study. Patients whose nighttime mean blood pressure, measured via ambulatory blood pressure monitoring, decreased between 10% and 20% compared with the daytime mean blood pressure were defined as “dippers”, whereas patients with a nighttime blood pressure decrease lower than 10% were defined as “non-dippers”.Results: A total of 99 hypertensive patients (65 females/34 males were classified as dippers and 72 patients (48 females/24 males as non-dippers. The mean age of the non-dipper group was significantly greater than the dipper group. Serum GGT, C-reactive protein and uric acid levels were significantly higher among patients in the non-dipper group. Negative correlations were detected between GGT levels and diurnal systolic and diastolic blood pressure decreases.Conclusion: Our findings revealed that GGT level was higher in the non-dipper group, and was negatively correlated with the nighttime decrease of diurnal blood pressure. C-reactive protein and uric acid levels were also higher in the non-dipper group. However, future randomized controlled prospective studies with larger patient populations are necessary to confirm our findings. Keywords: gamma-glutamyl transpeptidase, hypertension, ambulatory blood pressure monitoring, laboratory parameters

  15. Management of patients with severe traumatic brain injury guided by intraventricular intracranial pressure monitoring: a report of 136 cases

    Institute of Scientific and Technical Information of China (English)

    ZENG Tao; GAO Liang

    2010-01-01

    Objective:To evaluate the effect of the treatment modality guided by intraventricular intracranial pressure (ICP) monitoring on patients with severe traumatic brain injury (TBI).Methods:The clinical data of a group of 136 severely brain-injured patients admitted to Shanghai Neurosurgical Emergency Center from December 2004 to February 2006 were studied.Results:The intraventricular ICP monitor was placed in all the 136 patients via Kocher's pathway, Paine's pathway or intraoperative opened ventricle. In this series, the probe was placed during the procedure of craniotomy in 98 patients; for other 38 patients, the probe was placed initially to measure or to monitor ICE A stepwise protocol targeting at ICP control (≤20 mm Hg) and optimal cerebral perfusion pressure (CPP) maintenance (60-90 mm Hg) was deployed.Among them, 76 patients survived with good recovery, 14 with moderate disability, 24 with severe disability, 10 with vegetative state, and 12 died. Complications associated with intraventricular ICP monitoring included hemorrhage and infection. Hemorrhage occurred in 1 patient and infection in 5 patients. There were no unacceptable complications related to ICP monitoring.Conclusions:Ventricular access for ICP monitoring can be safely and accurately achieved. ICP monitoring via ventriculostomy may facilitate an early and accurate intervention for severely brain-injured patients. The intraventricular ICP monitoring is a low-risk procedure and can yield great benefits for management of patients with severe TBI.

  16. Continuous cuff-less blood pressure monitoring based on the pulse arrival time approach: the impact of posture.

    Science.gov (United States)

    Muehlsteff, J; Aubert, X A; Morren, G

    2008-01-01

    There is an unmet need for cuff-less blood pressure (BP) monitoring especially, in personal healthcare applications. The pulse arrival time (PAT) approach might offer a suitable solution to enable comfortable BP monitoring even at beat-level. However, the methodology is based on hemodynamic surrogate measures, which are sensitive to patient activities such as posture changes, not necessarily related to blood pressure variations. In this paper, we analyze the impact of posture on the PAT measure and related hemodynamic parameters such as the pre-ejection period in well-defined procedures. Additionally, the PAT of a monitored subject is investigated in an unsupervised scenario illustrating the complexity of such a measurement. Our results show the failure of blood pressure inference based on simple calibration strategies using the PAT measure only. We discuss opportunities to compensate for the observed effects towards the realization of wearable cuff-less blood pressure monitoring. These findings emphasize the importance of accessing context information in personal healthcare applications, where vital sign monitoring is typically unsupervised.

  17. Chronobiology of arterial hypertension in hemodialysis patients: implications for home blood pressure monitoring.

    Science.gov (United States)

    Agarwal, Rajiv; Light, Robert P

    2009-10-01

    Hemodialysis patients have a steady increase in blood pressure (BP) during the 44-hour interdialytic interval when ambulatory BP monitoring is used. Home BP recording allows for a longer period of monitoring between dialysis treatments and may better define the chronobiological characteristics of arterial hypertension. This study sought to determine the optimal time to perform home BP monitoring in hemodialysis patients to improve the strength of prediction of 44-hour interdialytic ambulatory BP. Diagnostic test study. This is an ancillary analysis of patients participating in the Dry-weight Reduction in Hypertensive Hemodialysis Patients (DRIP) trial. Home BP measured 3 times daily for 1 week by using a validated oscillometric monitor on 3 occasions at 4-week intervals after randomization. Home BP measured during the first third, second third, and last third of time elapsed after the dialysis treatment, as well as each third of the dialysis treatment, was compared with the overall ambulatory BP. Interdialytic ambulatory BP measured on 3 occasions at 4-week intervals after randomization. During the interdialytic interval, we found an increase in systolic ambulatory BP of 0.30 +/- 0.36 mm Hg/h and an increase in systolic home BP of 0.40 +/- 0.25 mm Hg/h. This relationship in home BP reached a plateau after approximately 48 hours. A similar pattern was seen for diastolic home BP. Probing dry weight steepened the slope of ambulatory BP, but did not alter the time-dependent relationship of home BP. Home BP was on average higher (bias) by 14.1 (95% confidence interval, 12.0 to 16.2)/5.7 mm Hg (95% confidence interval, 4.6 to 6.9). The SD of differences between methods (precision) was 4.6/2.8 mm Hg. Measurement of BP during each third of the interdialytic interval gave the best precision, measured by using model fit compared with ambulatory BP measurements. Our cohort was overrepresented by African American hemodialysis patients. Whether African American participants

  18. Pseudomigrânea com pleocitose liquórica: monitorização intermitente da pressão intracraniana. Relato de caso Pseudomigraine with CSF hypercytosis: intermittent measurement of the intracranial pressure. Case report

    Directory of Open Access Journals (Sweden)

    Elcio Juliato Piovesan

    2001-06-01

    Full Text Available A pseudomigrânea com pleocitose é uma desordem benigna e auto limitada, caracterizada por sintomas recorrentes, sugestivos de migrânea associada a comprometimento neurológico focal e a alterações no líquido cefalorraquidiano. Monitorizamos a pressão intracraniana em um paciente com este diagnóstico durante os seus períodos sintomáticos e assintomáticos. O paciente foi submetido a três punções lombares com análise citoquímica demonstrando aumento de leucócitos, predominando monomorfonucleares, sem a identificação de agente etiológico. Durante a primeira e a terceira punção lombar o paciente apresentava sintomas neurológicos e cefaléia com características de migrânea, sua pressão intracraniana era de 400 e 440 mmH2O respectivamente. Em um momento assintomático realizamos nova punção lombar ao qual demonstrou pressão intracraniana de 190 mmH20. Os mecanismos fisiopatológicos desta desordem permanecem ainda desconhecidos, existindo algumas evidências que ela esteja relacionada a fenômenos autoimunes, que durante os períodos sintomáticos produzem uma redução no fluxo sangüíneo cerebral assemelhando-se a depressão alastrante. Os achados neste relato de caso sugerem a possibilidade de influência das oscilações da pressão intracraniana nos possíveis mecanismos fisiopatológicos da pseudomigrânea com pleocitose.Pseudomigraine with pleocytosis is a self-limited and rather beningn disorder, characterized by recurrent bouts of migrainous headaches, associated to focal neurological symptoms and to cerebrospinal fluid abnormalities. We have submitted an individual with pseudomigraine to three lumbar punctures. The first and the third lumbar punctures, carried out during symptomatic periods, revealed a cerebrospinal fluid with aseptic lymphomonocytic pleocytosis, and an opening pressure of 400 and 440 mmH2O, respectively. The cerebrospinal fluid pressure measured during an asymptomatic period was normal (190 mm

  19. Therapeutic applications of macrophage colony-stimulating factor-1 (CSF-1) and antagonists of CSF-1 receptor (CSF-1R) signaling.

    Science.gov (United States)

    Hume, David A; MacDonald, Kelli P A

    2012-02-23

    Macrophage-colony stimulating factor (CSF-1) signaling through its receptor (CSF-1R) promotes the differentiation of myeloid progenitors into heterogeneous populations of monocytes, macrophages, dendritic cells, and bone-resorbing osteoclasts. In the periphery, CSF-1 regulates the migration, proliferation, function, and survival of macrophages, which function at multiple levels within the innate and adaptive immune systems. Macrophage populations elicited by CSF-1 are associated with, and exacerbate, a broad spectrum of pathologies, including cancer, inflammation, and bone disease. Conversely, macrophages can also contribute to immunosuppression, disease resolution, and tissue repair. Recombinant CSF-1, antibodies against the ligand and the receptor, and specific inhibitors of CSF-1R kinase activity have been each been tested in a range of animal models and in some cases, in patients. This review examines the potential clinical uses of modulators of the CSF-1/CSF-1R system. We conclude that CSF-1 promotes a resident-type macrophage phenotype. As a treatment, CSF-1 has therapeutic potential in tissue repair. Conversely, inhibition of CSF-1R is unlikely to be effective in inflammatory disease but may have utility in cancer.

  20. The promotion of breast cancer metastasis caused by inhibition of CSF-1R/CSF-1 signaling is blocked by targeting the G-CSF receptor.

    Science.gov (United States)

    Swierczak, Agnieszka; Cook, Andrew D; Lenzo, Jason C; Restall, Christina M; Doherty, Judy P; Anderson, Robin L; Hamilton, John A

    2014-08-01

    Treatment options are limited for patients with breast cancer presenting with metastatic disease. Targeting of tumor-associated macrophages through the inhibition of colony-stimulating factor-1 receptor (CSF-1R), a key macrophage signaling pathway, has been reported to reduce tumor growth and metastasis, and these treatments are now in clinical trials. Here, we report that, surprisingly, treatment with neutralizing anti-CSF-1R and anti-CSF-1 antibodies, or with two different small-molecule inhibitors of CSF-1R, could actually increase spontaneous metastasis without altering primary tumor growth in mice bearing two independently derived mammary tumors. The blockade of CSF-1R or CSF-1 led to increased levels of serum G-CSF, increased frequency of neutrophils in the primary tumor and in the metastasis-associated lung, as well as increased numbers of neutrophils and Ly6C(hi) monocytes in the peripheral blood. Neutralizing antibody against the G-CSF receptor, which regulates neutrophil development and function, reduced the enhanced metastasis and neutrophil numbers that resulted from CSF-1R blockade. These results indicate that the role of the CSF-1R/CSF-1 system in breast cancer is far more complex than originally proposed, and requires further investigation as a therapeutic target.

  1. [MRI evaluation of cervicothoracic CSF hypotension].

    Science.gov (United States)

    Maraval, A; Brugieres, P; Combes, C; Thomas, P; Blanc, R; Gaston, A

    2006-06-01

    We propose studying signs of cervicothoracic CSF hypotension by MRI. Axial T1-weighted GRE sequence with and without saturation bands positioned above and below the selected image plane, MR venography and MR Angiography with contrast administration are helpful to confirm the venous nature of the epidural thickening and to make the differential diagnosis with infectious or neoplastic epiduritis.

  2. Evaluation of continuous non-invasive arterial pressure monitoring during induction of general anaesthesia in patients undergoing cardiac surgery.

    Science.gov (United States)

    Kumar, G Anil; Jagadeesh, A M; Singh, Naveen G; Prasad, S R

    2015-01-01

    Continuous arterial pressure monitoring is essential in cardiac surgical patients during induction of general anaesthesia (GA). Continuous non-invasive arterial pressure (CNAP) monitoring is fast gaining importance due to complications associated with the invasive arterial monitoring. Recently, a new continuous non-invasive arterial pressure device (CNAP™) has been validated perioperatively in non-cardiac surgeries. The aim of our study is to compare and assess the performance of CNAP during GA with invasive arterial pressure (IAP) in patients undergoing cardiac surgeries. Sixty patients undergoing cardiac surgery were included. Systolic, diastolic, and mean arterial pressure (MAP) data were recorded every minute for 20 min simultaneously for both IAP and CNAP™. Statistical analysis was performed using mountain plot and Bland Altman plots for assessing limits of agreement and bias (accuracy) calculation. Totally 1200 pairs of data were analysed. The CNAP™ systolic, diastolic and MAP bias was 5.98 mm Hg, -3.72 mm Hg, and - 0.02 mm Hg respectively. Percentage within limits of agreement was 96.0%, 95.2% and 95.7% for systolic, diastolic and MAP. The mountain plot showed similar results as the Bland Altman plots. We conclude CNAP™ provides real-time estimates of arterial pressure comparable to IAP during induction of GA for cardiac surgery. We recommend CNAP can be used as an alternative to IAP in situations such as cardiac patients coming for non-cardiac surgeries, cardiac catheterization procedures, positive Allen's test, inability to cannulate radial artery and vascular diseases, where continuous blood pressure monitoring is required.

  3. Evaluation of the Colin STBP-680 at rest and during exercise: an automated blood pressure monitor using R-wave gating.

    OpenAIRE

    Bond, V.; Bassett, D R; Howley, E T; Lewis, J.; Walker, A J; Swan, P D; Tearney, R J; Adams, R.G.

    1993-01-01

    The application of automated blood pressure measurement during exercise has been limited by inaccuracies introduced by the effects of accompanying motion and noise. We evaluated a newly developed automated blood pressure monitor for measuring exercise blood pressure (Colin STBP-680; Colin, San Antonio, Texas, USA). The STBP-680 uses acoustic transduction with the assistance of the electrocardiogram R-wave to trigger the sampling period for blood pressure measurement. The automated monitor rea...

  4. Intensive care management of head injury patients without routine intracranial pressure monitoring

    Directory of Open Access Journals (Sweden)

    Santhanam R

    2007-01-01

    Full Text Available Background: Head injury contributes significantly to mortality and morbidity in India. Evaluation of the available trauma care facilities may help improve outcome. Aim: To evaluate the factors influencing the mortality of patients with head injury who had intensive care management and evolve strategies to improve outcome. Setting and Design: Retrospective study in a tertiary hospital where intracranial pressure monitoring (ICPM is not routinely practiced. Materials and Methods: All patients with head injury managed in the intensive care unit in a two-year period were included. The factors evaluated were age, vital signs, Glasgow Coma scale score (GCS at admission, pupillary light reflex (PR, oculocephalic reflex (OCR, hemodynamic stability, computerized tomography (CT findings, diabetes mellitus, anemia, infections and abnormalities of serum sodium. Results: We analyzed 208 patients (202 without ICPM. In-hospital mortality was 64 (31%. Only 24 (11.5% patients were admitted within one hour of injury, while one-third arrived after six hours. The clinical factors (at admission that influenced mortality included age, GCS, PR, OCR and diastolic blood pressure (DBP. Effacement of the basal cisterns in the initial and repeat CT scans, hyperglycemia, hemodynamic instability and serum sodium imbalances were associated with higher mortality. The independent predictors of mortality by logistic regression were initial GCS, DBP, hemodynamic instability and effacement of cisterns on repeat CT. Conclusions: Mortality following head injury is high. Pre-hospital emergency medical services are disorganized. The key to reducing mortality within the limitations of our current trauma system is maintenance of DBP>70 mmHg and SBP> 90 mmHg from the time of first contact.

  5. European Society of Hypertension position paper on ambulatory blood pressure monitoring.

    Science.gov (United States)

    O'Brien, Eoin; Parati, Gianfranco; Stergiou, George; Asmar, Roland; Beilin, Laurie; Bilo, Grzegorz; Clement, Denis; de la Sierra, Alejandro; de Leeuw, Peter; Dolan, Eamon; Fagard, Robert; Graves, John; Head, Geoffrey A; Imai, Yutaka; Kario, Kazuomi; Lurbe, Empar; Mallion, Jean-Michel; Mancia, Giuseppe; Mengden, Thomas; Myers, Martin; Ogedegbe, Gbenga; Ohkubo, Takayoshi; Omboni, Stefano; Palatini, Paolo; Redon, Josep; Ruilope, Luis M; Shennan, Andrew; Staessen, Jan A; vanMontfrans, Gert; Verdecchia, Paolo; Waeber, Bernard; Wang, Jiguang; Zanchetti, Alberto; Zhang, Yuqing

    2013-09-01

    Ambulatory blood pressure monitoring (ABPM) is being used increasingly in both clinical practice and hypertension research. Although there are many guidelines that emphasize the indications for ABPM, there is no comprehensive guideline dealing with all aspects of the technique. It was agreed at a consensus meeting on ABPM in Milan in 2011 that the 34 attendees should prepare a comprehensive position paper on the scientific evidence for ABPM.This position paper considers the historical background, the advantages and limitations of ABPM, the threshold levels for practice, and the cost-effectiveness of the technique. It examines the need for selecting an appropriate device, the accuracy of devices, the additional information and indices that ABPM devices may provide, and the software requirements.At a practical level, the paper details the requirements for using ABPM in clinical practice, editing considerations, the number of measurements required, and the circumstances, such as obesity and arrhythmias, when particular care needs to be taken when using ABPM.The clinical indications for ABPM, among which white-coat phenomena, masked hypertension, and nocturnal hypertension appear to be prominent, are outlined in detail along with special considerations that apply in certain clinical circumstances, such as childhood, the elderly and pregnancy, and in cardiovascular illness, examples being stroke and chronic renal disease, and the place of home measurement of blood pressure in relation to ABPM is appraised.The role of ABPM in research circumstances, such as pharmacological trials and in the prediction of outcome in epidemiological studies is examined and finally the implementation of ABPM in practice is considered in relation to the issue of reimbursement in different countries, the provision of the technique by primary care practices, hospital clinics and pharmacies, and the growing role of registries of ABPM in many countries.

  6. Ambulatory blood pressure monitoring and endothelium-dependent vasodilation in the elderly athletes.

    Science.gov (United States)

    Galetta, F; Franzoni, F; Plantinga, Y; Ghiadoni, L; Rossi, M; Prattichizzo, F; Carpi, A; Taddei, S; Santoro, G

    2006-09-01

    Regular exercise is a key component of cardiovascular risk prevention strategies, because it is associated with a variety of beneficial metabolic and vascular effects that reduce mortality and the incidence of cardiovascular adverse events. Endothelium plays an important role in the local regulation of vascular tone and structure, mainly by nitric oxide (NO) synthesis and action. Aim of the present study was to evaluate in elderly athletes the effect of regular aerobic exercise on arterial blood pressure (BP) and on endothelium-dependent flow-mediated dilation (FMD) of the brachial artery. The study population included 30 male subjects (mean age 65.6+/-5.6 years), who had practiced endurance running at a competitive level for at least 40 years, and 28 age- and sex-matched subjects (mean age 64.5+/-4.5 years) with sedentary lifestyle and free of cardiovascular disease. Athletes and control subjects underwent standard 12-lead ECG, clinic BP, 24-h ambulatory BP monitoring and endothelium-dependent FMD and endothelium-independent response to glyceryl trinitrate (GTN), 400 microg, in the brachial artery by high-resolution ultrasonography. Systolic clinic and ambulatory 24-h BP were significantly lower in the athletes, than in the controls (Pathletes (Pathletes also had a lower 24-h, day-time and night-time heart rate (HR) (Pathletes (Pathletes showed higher FMD than elderly sedentary subjects (Pphysical activity can counteract the age-related endothelial dysfunction that characterizes sedentary aging, preserving the capacity of the endothelium-dependent vasodilation and reduces BP values improving arterial pressure control.

  7. Noninvasive intracranial pressure monitoring via optic nerve sheath diameter for robotic surgery in steep Trendelenburg position

    Directory of Open Access Journals (Sweden)

    Shagun Bhatia Shah

    2015-01-01

    Full Text Available Background: Recent reports of increased intracranial pressure (ICP due to steep Trendelenburg (ST position causing neurological deterioration, decreased regional cerebral oxygen saturation and postoperative visual loss after robotic urological and gynecological surgeries led us to consider a simple technique of ICP monitoring. Ours is one of the first instances reported of quantitative noninvasive measurement of increase in ICP with ST position by serial measurement of binocular optic nerve sheath diameter (ONSD in patients undergoing robot assisted urological and gynecological oncosurgery. We tested whether ONSD values rose to above the upper limits of normal and for what length of time they remained elevated. Materials and Methods: Prospective, randomized, interventional, parallel group, active control study conducted on 252 American Society of Anesthesiologists I and II patients. ONSD was measured using 7.5 MHz linear ultrasound probe in supine and Trendelenburg positions. Statistics: Student′s t-test to compare the inter-group mean ONSD and the repetitive t-test for intra-group analysis. Result: Comparison of the mean ONSD values of both groups yielded a 2-tailed significance P <0.01 at all compared time points intra- and post-operatively. In Group-O (open surgery; supine position, the baseline mean bilateral ONSD was 4.36 mm, which did not show any statistically significant change throughout open surgery and postoperative period. On de-docking the robot, 6.2 mm was the mean ONSD value in Group-R (robotic group while 4.3 mm was the corresponding value in control Group-O. Conclusion: ONSD evaluation is a simple, quick, safe, readily available, reliable, cost effective, noninvasive, potential standard of care for screening and monitoring of patients undergoing robotic surgery in ST position.

  8. The tympanic membrane displacement analyser for monitoring intracranial pressure in children.

    Science.gov (United States)

    Gwer, Samson; Sheward, Victoria; Birch, Anthony; Marchbanks, Robert; Idro, Richard; Newton, Charles R; Kirkham, Fenella J; Lin, Jean-Pierre; Lim, Ming

    2013-06-01

    Raised intracranial pressure (ICP) is a potentially treatable cause of morbidity and mortality but tools for monitoring are invasive. We sought to investigate the utility of the tympanic membrane displacement (TMD) analyser for non-invasive measurement of ICP in children. We made TMD observations on normal and acutely comatose children presenting to Kilifi District Hospital (KDH) at the rural coast of Kenya and on children on follow-up for idiopathic intracranial hypertension at Evelina Children's Hospital (ECH), in London, UK. We recruited 63 patients (median age 3.3 (inter-quartile range (IQR) 2.0-4.3) years) at KDH and 14 children (median age 10 (IQR 5-11) years) at ECH. We observed significantly higher (more negative) TMD measurements in KDH children presenting with coma compared to normal children seen at the hospital's outpatient department, in both semi-recumbent [mean -61.3 (95 % confidence interval (95 % CI) -93.5 to 29.1) nl versus mean -7.1 (95 % CI -54.0 to 68.3) nl, respectively; P = 0.03] and recumbent postures [mean -61.4 (95 % CI -93.4 to -29.3) nl, n = 59) versus mean -25.9 (95 % CI -71.4 to 123.2) nl, respectively; P = 0.03]. We also observed higher TMD measurements in ECH children with raised ICP measurements, as indicated by lumbar puncture manometry, compared to those with normal ICP, in both semi-recumbent [mean -259.3 (95 % CI -363.8 to -154.8) nl versus mean 26.7 (95 % CI -52.3 to 105.7) nl, respectively; P analyser has a potential utility in monitoring ICP in a variety of clinical circumstances.

  9. [Anesthesia management of geriatric patients with arterial pressure-based cardiac output monitoring FloTrac sensor for emergency surgery].

    Science.gov (United States)

    Yamamoto, Shunsuke; Goto, Koji; Yasuda, Norihisa; Kusaka, Junya; Hidaka, Seigo; Miyakawa, Hiroshi; Noguchi, Takayuki

    2009-06-01

    In cases of emergency surgery for geriatric patients, immediate anesthesia induction and careful intraoperative management is necessary without sufficient preoperative information. We report anesthesia management of a 96-year and a 90-year old patients with FloTrac sensor which is an arterial pressure-based cardiac output monitoring device and is able to manage critical patients effectively and safely during anesthesia.

  10. Modalities of Invasive Arterial Pressure Monitoring in Critically Ill Patients: A Prospective Observational Study.

    Science.gov (United States)

    Jacq, Gwenaëlle; Gritti, Karine; Carré, Cécile; Fleury, Nadège; Lang, Annie; Courau-Courtois, Josette; Bedos, Jean-Pierre; Legriel, Stephane

    2015-09-01

    Few studies assessed modalities of invasive arterial pressure monitoring (IAPM). We evaluated effects on measured values of various combinations of transducer level, catheter access site, and patient position. Prospective observational study in consecutive adults admitted to a French intensive care unit in 2009 to 2011 and fulfilling our inclusion criteria. Four combinations (B-E) of transducer level, catheter access site, and patient position were compared with a reference combination (A) (A: patient supine with all catheters in the same plane and a single transducer level (M) for zero point reference (Z) aligned on the phlebostatic axis; B: 45° head-of-bed elevation with M and Z aligned on the phlebostatic axis; C: 45° head-of-bed elevation with M aligned on the catheter access site and Z on the phlebostatic axis; D: 45° head-of-bed elevation with M and Z aligned on the catheter access site; and E: 45° head-of-bed elevation with M aligned on the phlebostatic axis and Z on the catheter access site). We included 103 patients, 68 men and 35 women, with a median age of 69 years (interquartile range [IQR], 56-78); at inclusion, 91 (88.3%) received mechanical ventilation, 45 (43.7%) catecholamines, and 66 (64.1%) sedation. The IAPM access site was femoral in 49 (47.6%) and radial in 54 (52.4%) patients, with 62 of 103 (60.2%) catheters on the right side. Measured absolute mean arterial pressure values were significantly higher with 3 study combinations (C-E) than with the reference combination (A). After adjustment, the differences versus A (median, 83 [IQR, 74-92] mm Hg) remained significant for D (median, 91 [IQR, 85-100] mm Hg, P arterial pressure values. For patients in the 45° head-of-bed elevation position, aligning the Z on the phlebostatic axis provides values that are not significantly different from those obtained using the reference supine modality.

  11. Long-term pressure monitoring with arterial applanation tonometry: a non-invasive alternative during clinical intervention?

    Science.gov (United States)

    Matthys, Koen S; Kalmar, Alain F; Struys, Michel M R F; Mortier, Eric P; Avolio, Alberto P; Segers, Patrick; Verdonck, Pascal R

    2008-01-01

    Arterial tonometry is a non-invasive technique for continuous registration of arterial pressure waveforms. This study aims to assess tonometric blood pressure recording (TBP) as an alternative for invasive long-term bedside monitoring. A prospective study was set up where patients undergoing neurosurgical intervention were subjected to both invasive (IBP) and non-invasive (TBP) blood pressure monitoring during the entire procedure. A single-element tonometric pressure transducer was used to better investigate different inherent error sources of TBP measurement. A total of 5.7 hours of combined IBP and TBP were recorded from three patients. Although TBP performed fairly well as an alternative for IBP in steady state scenarios and some short-term variations, it could not detect relevant long-term pressure variations at all times. These findings are discussed in comparison to existing work. Physiological alterations at the site of TBP measurement are highlighted as a potentially important source of artifacts. It is concluded that at this point arterial tonometry remains not enough understood for long-term use during a delicate operative procedure. Physiological changes at the TBP measurement site deserve further investigation before tonometry technology is to be considered as an non-invasive alternative for long-term clinical monitoring.

  12. CSF neurofilament protein analysis in the differential diagnosis of ALS.

    NARCIS (Netherlands)

    Reijn, T.S.M.; Abdo, W.; Schelhaas, H.J.; Verbeek, M.M.

    2009-01-01

    BACKGROUND: Cerebrospinal fluid (CSF) biomarkers have been studied to differentiate between patients with ALS and neurological controls, but not in comparison to clinically more relevant disorders mimicking ALS. METHODS: In this retrospective study, CSF concentrations of various brain-specific

  13. CSF neurofilament proteins in the differential diagnosis of dementia

    NARCIS (Netherlands)

    de Jong, D; Jansen, R W M M; Pijnenburg, Y A L; van Geel, W J A; Borm, G F; Kremer, Berry; Verbeek, M.

    BACKGROUND: Neurofilament (NF) proteins are major cytoskeletal constituents of neurons. Increased CSF NF levels may reflect neuronal degeneration. OBJECTIVE: To investigate the diagnostic value of CSF NF analysis to discriminate in relatively young dementia patients between frontotemporal lobe

  14. CSF neurofilament proteins in the differential diagnosis of dementia.

    NARCIS (Netherlands)

    Jong, D. de; Jansen, R.W.M.M.; Pijnenburg, Y.A.; Geel, W.J.A. van; Borm, G.F.; Kremer, H.P.H.; Verbeek, M.M.

    2007-01-01

    BACKGROUND: Neurofilament (NF) proteins are major cytoskeletal constituents of neurons. Increased CSF NF levels may reflect neuronal degeneration. OBJECTIVE: To investigate the diagnostic value of CSF NF analysis to discriminate in relatively young dementia patients between frontotemporal lobe

  15. CSF-1R Inhibitor Development: Current Clinical Status.

    Science.gov (United States)

    Peyraud, Florent; Cousin, Sophie; Italiano, Antoine

    2017-09-05

    Colony-stimulating factor 1 receptor (CSF-1R) and its ligands, CSF-1 and interleukin 34 (IL-34), regulate the function and survival of tumor-associated macrophages, which are involved in tumorigenesis and in the suppression of antitumor immunity. Moreover, the CSF-1R/CSF-1 axis has been implicated in the pathogenesis of pigmented villonodular synovitis (PVNS), a benign tumor of the synovium. As advanced or metastatic malignant solid tumors and relapsed/refractory PVNS remain unresolved therapeutic problems, new approaches are needed to improve the outcome of patients with these conditions. In solid tumors, targeting CSF-1R via either small molecules or antibodies has shown interesting results in vitro but limited antitumor activity in vivo. Concerning PVNS, clinical trials assessing CSF-1R inhibitors have revealed promising initial outcomes. Blocking CSF-1/CSF-1R signaling represents a promising immunotherapy approach and several new potential combination therapies for future clinical testing.

  16. Monitoring inner ear pressure changes in normal guinea pigs induced by the Meniett (R) 20

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Wit, HP; Albers, FWJ

    2000-01-01

    The inner ear fluid pressure of guinea pigs was measured during a series of complex escalating middle ear pressure changes induced by the Meniett(R)20 (Pascal Medical, Sweden), a possible therapeutic pressure generator to be used by patients with Meniere's disease. Middle ear pressure changes were t

  17. Monitoring inner ear pressure changes in normal guinea pigs induced by the Meniett (R) 20

    NARCIS (Netherlands)

    Feijen, RA; Segenhout, JM; Wit, HP; Albers, FWJ

    2000-01-01

    The inner ear fluid pressure of guinea pigs was measured during a series of complex escalating middle ear pressure changes induced by the Meniett(R)20 (Pascal Medical, Sweden), a possible therapeutic pressure generator to be used by patients with Meniere's disease. Middle ear pressure changes were

  18. A Non-Invasive Ultrasonic Urinary Bladder Internal Pressure Monitoring Technique: Its Theoretical Foundation and Feasibility Test

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Min Joo; Kang, Gwan Suk [Jeju National University, Jeju (Korea, Republic of); Lee, Kang Il [Department of Physics, Kangwon National University, Chuncheon (Korea, Republic of)

    2012-10-15

    A new approach was proposed in this article, named, a non-invasive ultrasonic method to monitor the urinary bladder internal pressure which can resolve the shortcomings of the existing methods. The proposed method makes use of acoustic cavitation. It is based on a physical phenomenon that an extracorporeal high intensity focused ultrasonic pulse generates bubbles inside the urinary bladder and the dynamic properties of the bubbles are related to the urinary bladder internal pressure. The article presents the theoretical foundation for the proposed technique and verifies its feasibility with preliminary experimental data. The suggested ultrasonic urinary bladder internal pressure monitoring method is non-invasive and can be used any time regardless of sex and age.

  19. A new state-observer of the inner PEM fuel cell pressures for enhanced system monitoring

    Science.gov (United States)

    Bethoux, Olivier; Godoy, Emmanuel; Roche, Ivan; Naccari, Bruno; Amira Taleb, Miassa; Koteiche, Mohamad; Nassif, Younane

    2014-06-01

    In embedded systems such as electric vehicles, Proton exchange membrane fuel cell (PEMFC) has been an attractive technology for many years especially in automotive applications. This paper deals with PEMFC operation monitoring which is a current target for improvement for attaining extended durability. In this paper, supervision of the PEMFC is done using knowledge-based models. Without extra sensors, it enables a clear insight of state variables of the gases in the membrane electrode assembly (MEA) which gives the PEMFC controller the ability to prevent abnormal operating conditions and associated irreversible degradations. First, a new state-observer oriented model of the PEM fuel cell is detailed. Based on this model, theoretical and practical observability issues are discussed. This analysis shows that convection phenomena can be considered negligible from the dynamic point of view; this leads to a reduced model. Finally a state-observer enables the estimation of the inner partial pressure of the cathode by using only the current and voltage measurements. This proposed model-based approach has been successfully tested on a PEM fuel cell simulator using a set of possible fault scenarios.

  20. A Tilt, Soil Moisture, and Pore Water Pressure Sensor System for Slope Monitoring Applications

    Directory of Open Access Journals (Sweden)

    Rosanno de Dios

    2009-06-01

    Full Text Available This paper describes the design, implementation and characterization of a sensor network intended for monitoring of slope deformation and potential failures. The sensor network system consists of a tilt and moisture sensor column, a pore water pressure sensor column and a personal computer for data storage and processing. The tilt sensor column consists of several pipe segments containing tri-axial accelerometers and signal processing electronics. Each segment is joined together by flexible joints to allow for the column to deform and subsequently track underground movement. Capacitive-type sensors for soil moisture measurement are also included in the sensor column, which are used to measure the soil moisture at different depths. The measurements at each segment are transferred via a Controller Area Network (CAN bus, where the CAN master node is located at the top of the column above ground. The CAN master node transmits the collected data from the slave nodes via a wireless connection to a personal computer that performs data storage, processing and display via a Python-based graphical user interface (GUI. The entire system was deployed and characterized on a small-scale slope model. Slope failure was induced via water seepage and the system was demonstrated to ably measure the inclination and soil moisture content throughout the landslide event.

  1. Toward a Wirelessly Powered On-Lens Intraocular Pressure Monitoring System.

    Science.gov (United States)

    Chiou, Jin-Chern; Hsu, Shun-Hsi; Liao, Yu-Te; Huang, Yu-Chieh; Yeh, Guan-Ting; Kuei, Cheng-Kai; Dai, Kai-Shiun

    2016-09-01

    This paper presents a wireless on-lens intraocular pressure monitoring system, comprising a capacitance-to-digital converter and a wirelessly powered radio-frequency identification (RFID)-compatible communication system, for sensor control and data communication. The capacitive sensor was embedded on a soft contact lens of 200 μm thickness using commercially available biocompatible lens material, to improve compliance and reduce user discomfort. The sensor chip was shown to achieve effective number of bits greater than 10 over a capacitance range up to 50 pF while consuming only 64-μW power. The on-lens capacitive sensor could detect dielectric variation caused by changes in water content from a distance of 2 cm by using incident power from an RFID reader at 20 dBm. The maximum detectable distance was 11 cm with 30-dBm incident RF power. The rise in eye tissue temperature under 30-dBm RF exposure over an interval of 1 s was simulated and found to be less than 0.01°C.

  2. Antibody-free quantification of seven tau peptides in human CSF using targeted mass spectrometry

    Directory of Open Access Journals (Sweden)

    Pauline eBros

    2015-09-01

    Full Text Available Tau protein concentration in cerebrospinal fluid (CSF is currently used as a sensitive and specific biomarker for Alzheimer's disease. Its detection currently relies on ELISA but the perspective of using mass spectrometry (MS to detect its different proteoforms represents an interesting alternative. This is however an analytical challenge because of its low concentration in the CSF, a biological fluid collected in small volume by lumbar puncture, and with a high structural heterogeneity. To overcome these issues, instead of using immunocapture as previously done, we rather relied on an original two steps pre-fractionation technique of CSF: perchloric acid followed by micro solid phase extraction (µSPE. We could then measure seven tau trypsic peptides by Multiple Reaction Monitoring (MRM on a triple quadrupole mass spectrometer. Quantification was performed using isotopically labelled 15N- recombinant Tau protein as internal standard and validated using CSF pools with low, medium or high tau concentrations. Repeatability, intermediate precision, linearity, limit of quantification and recovery were calculated for the different peptides. This new MRM assay, which allowed for the first time CSF tau protein quantification without immunocapture, has important potential application to follow tau metabolism in both diagnostic and therapeutic research.

  3. Antibody-free quantification of seven tau peptides in human CSF using targeted mass spectrometry.

    Science.gov (United States)

    Bros, Pauline; Vialaret, Jérôme; Barthelemy, Nicolas; Delatour, Vincent; Gabelle, Audrey; Lehmann, Sylvain; Hirtz, Christophe

    2015-01-01

    Tau protein concentration in cerebrospinal fluid (CSF) is currently used as a sensitive and specific biomarker for Alzheimer's disease. Its detection currently relies on ELISA but the perspective of using mass spectrometry (MS) to detect its different proteoforms represents an interesting alternative. This is however an analytical challenge because of its low concentration in the CSF, a biological fluid collected in small volume by lumbar puncture, and with a high structural heterogeneity. To overcome these issues, instead of using immunocapture as previously done, we rather relied on an original two steps pre-fractionation technique of CSF: perchloric acid (PCA) followed by micro solid phase extraction (μSPE). We could then measure seven tau trypsic peptides by Multiple Reaction Monitoring (MRM) on a triple quadrupole mass spectrometer. Quantification was performed using isotopically labeled (15)N- recombinant tau protein as internal standard and validated using CSF pools with low, medium, or high tau concentrations (HTCs). Repeatability, intermediate precision, linearity, limit of quantification (LOQ), and recovery were calculated for the different peptides. This new MRM assay, which allowed for the first time CSF tau protein quantification without immunocapture, has important potential application to follow tau metabolism in both diagnostic and therapeutic research.

  4. Sphingomyelin as a myelin biomarker in CSF of acquired demyelinating neuropathies.

    Science.gov (United States)

    Capodivento, Giovanna; Visigalli, Davide; Garnero, Martina; Fancellu, Roberto; Ferrara, Michela Demetra; Basit, Abdul; Hamid, Zeeshan; Pastore, Vito Paolo; Garibaldi, Silvano; Armirotti, Andrea; Mancardi, Gianluigi; Serrati, Carlo; Capello, Elisabetta; Schenone, Angelo; Nobbio, Lucilla

    2017-08-10

    Fast, accurate and reliable methods to quantify the amount of myelin still lack, both in humans and experimental models. The overall objective of the present study was to demonstrate that sphingomyelin (SM) in the cerebrospinal fluid (CSF) of patients affected by demyelinating neuropathies is a myelin biomarker. We found that SM levels mirror both peripheral myelination during development and small myelin rearrangements in experimental models. As in acquired demyelinating peripheral neuropathies myelin breakdown occurs, SM amount in the CSF of these patients might detect the myelin loss. Indeed, quantification of SM in 262 neurological patients showed a significant increase in patients with peripheral demyelination (p = 3.81 * 10 - 8) compared to subjects affected by non-demyelinating disorders. Interestingly, SM alone was able to distinguish demyelinating from axonal neuropathies and differs from the principal CSF indexes, confirming the novelty of this potential CSF index. In conclusion, SM is a specific and sensitive biomarker to monitor myelin pathology in the CSF of peripheral neuropathies. Most importantly, SM assay is simple, fast, inexpensive, and promising to be used in clinical practice and drug development.

  5. CSF clearance in Alzheimer Disease measured with dynamic PET.

    Science.gov (United States)

    de Leon, Mony J; Li, Yi; Okamura, Nobuyuki; Tsui, Wai H; Saint Louis, Les A; Glodzik, Lidia; Osorio, Ricardo S; Fortea, Juan; Butler, Tracy; Pirraglia, Elizabeth; Fossati, Silvia; Kim, Hee-Jin; Carare, Roxana O; Nedergaard, Maiken; Benveniste, Helene; Rusinek, Henry

    2017-03-16

    Evidence supporting the hypothesis that reduced cerebrospinal fluid (CSF) clearance is involved in the pathophysiology of Alzheimer's disease (AD) comes from primarily from rodent models. However, unlike rodents where predominant extra-cranial CSF egress is via olfactory nerves traversing the cribriform plate, human CSF clearance pathways are not well characterized. Using dynamic Positron Emission Tomography (PET) with (18)F-THK5117 a tracer for tau pathology, the ventricular CSF time activity was used as a biomarker for CSF clearance. We tested three hypotheses: 1. Extra-cranial CSF is detected at the superior turbinates; 2. CSF clearance is reduced in AD; and 3. CSF clearance is inversely associated with amyloid deposition. Methods: 15 subjects, 8 with AD and 7 normal control volunteers were examined with (18)F-THK5117. 10 subjects additionally received (11)C-PiB PET scans and 8 were PiB positive. Ventricular time activity curves (TAC) of (18)F-THK5117 were used to identify highly correlated TAC from extra-cranial voxels. Results: For all subjects, the greatest density of CSF positive extra-cranial voxels was in the nasal turbinates. Tracer concentration analyses validated the superior nasal turbinate CSF signal intensity. AD patients showed ventricular tracer clearance reduced by 23% and 66% fewer superior turbinate CSF egress sites. Ventricular CSF clearance was inversely associated with amyloid deposition. Conclusion: The human nasal turbinate is part of the CSF clearance system. Lateral ventricle and superior nasal turbinates CSF clearance abnormalities are found in AD. Ventricular CSF clearance reductions are associated with increased brain amyloid depositions. These data suggest that PET measured CSF clearance is a biomarker of potential interest in AD and other neurodegenerative diseases.

  6. ANAESTHESIA MANAGEMENT OF CSF RHINORRHEA REPAIR : A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Kirti Arvind

    2015-09-01

    Full Text Available Anaesthesiologist plays a major role in Cerebrospinal Fluid (CSF rhinorrhea repair surgery as the prognosis of which is dependent on provision of clear bloodless surgical field and surgeons satisfaction. Anaesthesiologist also plays vital role in the management of CSF Lumbar drain. This case highlights the importance of hypotensive anaesthesia during endoscopic repair of a case of spontaneous CSF Rhinorrhea with successful perioperative management of Lumbar drainage of CSF

  7. Neurosyphilis in AIDS patients: initial CSF VDRL may be negative.

    Science.gov (United States)

    Feraru, E R; Aronow, H A; Lipton, R B

    1990-03-01

    We report 2 HIV-seropositive patients with neurosyphilis whose initial CSF VDRL tests were negative. The CSF VDRL became positive after 12 days of IV penicillin treatment for syphilitic meningitis in the 1st patient. The 2nd patient developed syphilitic polyradiculopathy and a positive CSF VDRL 3 months after treatment with IV penicillin. Serial CSF VDRL determinations may be required in AIDS patients when a diagnosis of neurosyphilis is suspected.

  8. Reducing CSF shunt placement in patients with spinal myelomeningocele

    Directory of Open Access Journals (Sweden)

    Suresh Sankhla

    2009-01-01

    Full Text Available Object: The incidence of hydrocephalus requiring shunts in children with myelomeningocele (MMC is reported to be very high. Shunt-related complications are a significant cause of morbidity and mortality in this population. In order to minimize shunt placements, we used very rigid clinical selection criteria and followed them in all patients who had myelomeningocele and enlarged ventricles. The follow-up outcome of this retrospective study is reported. Methods: From 2000 to 2007, 23 patients with myelomeningocele and variable degree of hydrocephalus were treated at our institute with primary surgical closure of their myelomeningoceles without a CSF diversion procedure. Patients with severe hydrocephalus who required immediate shunt insertion, and those with no significant associated hydrocephalus were not included in this study. Data regarding the surgical results and complications, postoperative management, and the outcome at follow-up were obtained from their hospital records. Results: Initially increased size of the ventricular system was found to have decreased or stabilized in 17 (81% patients postoperatively. However, ventriculomegaly continued to progress further in 4 (19% out of 21 patients. Of 11 patients who presented with enlarged head, eight (73% patients showed reduction or stabilization in their head circumference. Three (27% children continued to have progressive head enlargement in the postoperative period and required shunt placement. Signs of raised intracranial pressure observed in six patients on admission, improved in two (33% and persisted or worsened in four (67% patients who eventually improved after the insertion of a shunt. Eight (35% patients experienced wound-related complications following closure of the MMC, including CSF leak in four, wound infection in three, wound breakdown in three, and pseudomeningocele in two patients. Shunt placement was required in the postoperative period in 13 (56.5% patients to treat

  9. Noninvasive continuous versus intermittent arterial pressure monitoring: evaluation of the vascular unloading technique (CNAP device) in the emergency department.

    Science.gov (United States)

    Wagner, Julia Y; Prantner, Julia S; Meidert, Agnes S; Hapfelmeier, Alexander; Schmid, Roland M; Saugel, Bernd

    2014-01-29

    Monitoring cardiovascular function in acutely ill patients in the emergency department (ED) is of paramount importance. Arterial pressure (AP) is usually monitored using intermittent oscillometric measurements with an upper arm cuff. The vascular unloading technique (VUT) allows continuous noninvasive AP monitoring. In this study, we compare continuous AP measurements obtained by VUT with intermittent oscillometric AP measurements in ED patients. In addition, we aimed to investigate whether continuous noninvasive AP monitoring allows detection of relevant hypotensive episodes that might be missed with intermittent AP monitoring. In a German university hospital, 130 ED patients who required AP monitoring were analyzed in this prospective method comparison study. Continuous AP monitoring was performed using VUT (CNAP technology; CNSystems Medizintechnik AG, Graz, Austria) over a 2-hour period. The oscillometric AP values were recorded simultaneously every 15 minutes for the comparison of both methods. For statistical evaluation, Bland-Altman plots accounting for repeated AP measurements per individual were used. The mean difference (±standard deviation) between AP measurements obtained by VUT and oscillometric AP measurements was -5 mmHg (±22 mmHg) for systolic AP (SAP), -2 mmHg (±15 mmHg) for diastolic AP (DAP), and -6 mmHg (±16 mmHg) for mean AP (MAP), respectively. In the interval between two oscillometric measurements, the VUT device detected hypotensive episodes (≥4 minutes) defined as either SAP monitoring allows immediate recognition of clinically relevant hypotensive episodes, which are missed or only belatedly recognized with intermittent AP measurement.

  10. Intracranial pressure monitoring, cerebral perfusion pressure estimation, and ICP/CPP-guided therapy: a standard of care or optional extra after brain injury?

    Science.gov (United States)

    Kirkman, M A; Smith, M

    2014-01-01

    Measurement of intracranial pressure (ICP) and mean arterial pressure (MAP) is used to derive cerebral perfusion pressure (CPP) and to guide targeted therapy of acute brain injury (ABI) during neurointensive care. Here we provide a narrative review of the evidence for ICP monitoring, CPP estimation, and ICP/CPP-guided therapy after ABI. Despite its widespread use, there is currently no class I evidence that ICP/CPP-guided therapy for any cerebral pathology improves outcomes; indeed some evidence suggests that it makes no difference, and some that it may worsen outcomes. Similarly, no class I evidence can currently advise the ideal CPP for any form of ABI. 'Optimal' CPP is likely patient-, time-, and pathology-specific. Further, CPP estimation requires correct referencing (at the level of the foramen of Monro as opposed to the level of the heart) for MAP measurement to avoid CPP over-estimation and adverse patient outcomes. Evidence is emerging for the role of other monitors of cerebral well-being that enable the clinician to employ an individualized multimodality monitoring approach in patients with ABI, and these are briefly reviewed. While acknowledging difficulties in conducting robust prospective randomized studies in this area, such high-quality evidence for the utility of ICP/CPP-directed therapy in ABI is urgently required. So, too, is the wider adoption of multimodality neuromonitoring to guide optimal management of ICP and CPP, and a greater understanding of the underlying pathophysiology of the different forms of ABI and what exactly the different monitoring tools used actually represent.

  11. Relationship between intracranial pressure and phase contrast cine MRI derived measures of intracranial pulsations in idiopathic normal pressure hydrocephalus.

    Science.gov (United States)

    Jaeger, Matthias; Khoo, Angela K; Conforti, David A; Cuganesan, Ramesh

    2016-11-01

    Phase contrast cine MRI with determination of pulsatile aqueductal cerebrospinal fluid (CSF) stroke volume and flow velocity has been suggested to assess intracranial pulsations in idiopathic normal pressure hydrocephalus (iNPH). We aimed to compare this non-invasive measure of pulsations to intracranial pressure (ICP) pulse wave amplitude from continuous ICP monitoring. We hypothesised that a significant correlation between these two markers of intracranial pulsations exists. Fifteen patients with suspected iNPH had continuous computerised ICP monitoring with calculation of mean ICP pulse wave amplitude (MWA) from time-domain analysis. MRI measured CSF aqueductal stroke volume and peak flow velocity. Mean MWA was 5.4mmHg (range 2.3-12.4mmHg). Mean CSF stroke volume and peak flow velocity were 65μl (range 3-195μl) and 9.31cm/s (range 1.68-15.0cm/s), respectively. No significant correlation between the invasive and non-invasive measures of pulsations existed (Spearman r=-0.30 and r=-0.27, respectively; p>0.05). We observed marked intra-individual fluctuation of MWA during continuous ICP monitoring of an average of 6.0mmHg (range 2.8-12.2mmHg). The results suggest a complex interplay between measures of pulsations derived from snapshot MRI measurements and continuous computerised ICP measurements, as no significant relationship existed in our data. Further study is needed to better understand the temporal profile of CSF MRI flow studies, as substantial variation in MWA over the course of several hours of ICP monitoring is common, suggesting that these physiologic fluctuations might obscure MRI snapshot measures of intracranial pulsations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Intracranial pressure monitoring and inpatient mortality in severe traumatic brain injury: A propensity score-matched analysis.

    Science.gov (United States)

    Dawes, Aaron J; Sacks, Greg D; Cryer, H Gill; Gruen, J Peter; Preston, Christy; Gorospe, Deidre; Cohen, Marilyn; McArthur, David L; Russell, Marcia M; Maggard-Gibbons, Melinda; Ko, Clifford Y

    2015-03-01

    Although intracranial pressure (ICP) monitoring in severe traumatic brain injury (TBI) is recommended by the Brain Trauma Foundation, the benefits remain controversial. We sought to determine the impact of ICP monitor placement on inpatient mortality within a regional trauma system after correcting for selection bias through propensity score matching. Data were collected on all severe TBI cases presenting to 14 trauma centers during the 2-year study period (2009-2010). Inclusion criteria were as follows: blunt injury, Glasgow Coma Scale (GCS) score of 8 or lower in the emergency department, and abnormal intracranial findings on head computed tomography (CT). Two separate multivariate logistic regression models were used to predict ICP monitor placement and inpatient mortality after controlling for demographics, severity of injury, comorbidities, and TBI-specific variables (GCS score, pupil reactivity, international normalized ratio, and nine specific head CT findings). To account for selection bias, we developed a propensity score-matched model to estimate the "true" effect of ICP monitoring on in-hospital mortality. A total of 844 patients met inclusion criteria; 22 died on arrival to the emergency department. Inpatient mortality was 38.8%; 46.0% of the patients underwent ICP monitor placement. Unadjusted mortality rates were significantly lower in the ICP monitoring group (30.7% vs. 45.7%, p propensity score matching, ICP monitor placement was associated with an 8.3 percentage point reduction in the risk-adjusted mortality rate. ICP monitor placement occurred in only 46% of eligible patients but was associated with significantly decreased mortality after adjusting for baseline risk profile and the propensity to undergo monitoring. As the individual impact of ICP monitoring may vary, future efforts must determine who stands to benefit from invasive monitoring techniques. Therapeutic/care management study, level III.

  13. [The peripheral perfusion pressure: a new non-invasive parameter for the circulatory monitoring of patients (author's transl)].

    Science.gov (United States)

    Huch, A; Lübbers, D W; Huch, R

    1975-01-01

    Heating of a skin area to a temperature of 42 degrees to 44 degrees C produces a certain physiological condition which induces maximal vasodilatation. Detailed experiments have shown that local peripheral vascular resistance of such an area remains constant for several hours. The flow in this area is proportional to the actual perfusion pressure. Relative flow was measured by means of a new type of electrode fixed to the skin like and ECG electrode, and compared with simultaneous intra-arterial blood pressure measruements. The changes in arterial blood pressure were also recorded by the skin electrode. This new parameter is defined as "peripheral perfusion pressure". It is appropiate for non-invasive continuous monitoring of the circulatory system of patients.

  14. Cerebrospinal fluid conductance and compliance of the craniospinal space in normal-pressure hydrocephalus. A comparison between two methods for measuring conductance to outflow.

    Science.gov (United States)

    Børgesen, S E; Gjerris, F; Sørensen, S C

    1979-10-01

    Conductance to outflow of cerebrospinal fluid (CSF) has been measured by both a lumboventricular perfusion and a bolus injection method in 24 patients with normal-pressure hydrocephalus. One purpose was to investigate whether the less time-consuming technique of bolus, injection gave results comparable to the results obtained by the lumboventricular perfusion technique. There was a poor correlation between the results obtained by the two measurements of conductance to outflow of CSF. It is concluded that the bolus-injection technique cannot substitute for the lumboventricular perfusion test. Compliance of the CSF space was measured by the bolus injection. The presence of B-waves, recorded from long-term intraventricular pressure monitoring, could be correlated to the sum of conductance to outflow and compliance. The correlation offers a possible explanation of the nature of B-waves.

  15. Long-term blood pressure changes induced by the 2009 L'Aquila earthquake: assessment by 24 h ambulatory monitoring.

    Science.gov (United States)

    Giorgini, Paolo; Striuli, Rinaldo; Petrarca, Marco; Petrazzi, Luisa; Pasqualetti, Paolo; Properzi, Giuliana; Desideri, Giovambattista; Omboni, Stefano; Parati, Gianfranco; Ferri, Claudio

    2013-09-01

    An increased rate of cardiovascular and cerebrovascular events has been described during and immediately after earthquakes. In this regard, few data are available on long-term blood pressure control in hypertensive outpatients after an earthquake. We evaluated the long-term effects of the April 2009 L'Aquila earthquake on blood pressure levels, as detected by 24 h ambulatory blood pressure monitoring. Before/after (mean±s.d. 6.9±4.5/14.2±5.1 months, respectively) the earthquake, the available 24 h ambulatory blood pressure monitoring data for the same patients were extracted from our database. Quake-related daily life discomforts were evaluated through interviews. We enrolled 47 patients (25 female, age 52±14 years), divided into three groups according to antihypertensive therapy changes after versus before the earthquake: unchanged therapy (n=24), increased therapy (n=17) and reduced therapy (n=6). Compared with before the quake, in the unchanged therapy group marked increases in 24 h (P=0.004), daytime (P=0.01) and nighttime (P=0.02) systolic blood pressure were observed after the quake. Corresponding changes in 24 h (P=0.005), daytime (P=0.01) and nighttime (P=0.009) diastolic blood pressure were observed. Daily life discomforts were reported more frequently in the unchanged therapy and increased therapy groups than the reduced therapy group (P=0.025 and P=0.018, respectively). In conclusion, this study shows that patients with unchanged therapy display marked blood pressure increments up to more than 1 year after an earthquake, as well as long-term quake-related discomfort. Our data suggest that particular attention to blood pressure levels and adequate therapy modifications should be considered after an earthquake, not only early after the event but also months later.

  16. PP058. Cradle: Community blood pressure monitoring in rural Africa: Detection of underlying pre-eclampsia.

    Science.gov (United States)

    Hezelgrave, Natasha; de Greef, Annemarie; Irvine, Lucy; Seed, Paul; Radford, Samara; Shennan, Andrew

    2013-04-01

    In many developing countries pre-eclampsia is under-detected partly due to inadequate training in accurate blood pressure (BP) measurements and insufficient, poorly functioning equipment. To evaluate whether the introduction of easy to use, low cost novel BP devices (Microlife 3AS1-2; designed by our research group specifically for use in developing countries and validated in pregnancy (B/A grade) according to BHS criteria) into rural clinics in Tanzania, Zimbabwe and Zambia increases referrals for suspected pre-eclampsia to a central referral hospital (as reflected by an increase in mean BP in pregnant women seen in the central referral site). International prospective longitudinal pre- and post-intervention pilot study. BP measurements were taken from consecutive women ⩾20 weeks' gestation who accessed care at a referral site (N=694). 20 BP devices were distributed to 20 rural antenatal clinics in each country. Post-intervention data was collected the following year (N=547). After adjustment for confounders, there was a significant increase in primary outcome; post-intervention mean diastolic BP for all women (2.39mmHg, p<0.001, 95% CI 0.97-3.8), implying an increased proportion of referred hypertensive women; and a reduction in proportion of women (median gestation 35 weeks') who had never previously had a BP taken in pregnancy (25.1% to 16.9%, OR 0.58, p=0.001, CI 0.42-0.79). Equipping community healthcare providers with this novel validated BP device is feasible, widely accepted and results in increased referrals for suspected pre-eclampsia. A cluster RCT to evaluate the effect of these monitors equipped with a traffic-light 'early warning system' is planned. Copyright © 2013. Published by Elsevier B.V.

  17. Intracranial Pressure Monitoring: Relationship Between Indices of Cerebrovascular Reserve, System Bandwidth, and Cerebral Perfusion

    Science.gov (United States)

    2007-11-02

    reactivity index ( PrX ), derived from correlation of the dynamic features of the intracranial pressure (ICP) and arterial blood pressure (ABP...brain has lost the ability to regulate blood flow, these pressure signals are similar [1,2]. The PrX index is numerically derived from the correlation

  18. Large scale modelling of salmon lice (Lepeophtheirus salmonis infection pressure based on lice monitoring data from Norwegian salmonid farms

    Directory of Open Access Journals (Sweden)

    Anja B. Kristoffersen

    2014-12-01

    Full Text Available Infection by parasitic sea lice is a substantial problem in industrial scale salmon farming. To control the problem, Norwegian salmonid farms are not permitted to exceed a threshold level of infection on their fish, and farms are required to monitor and report lice levels on a weekly basis to ensure compliance with the regulation. In the present study, we combine the monitoring data with a deterministic model for salmon lice population dynamics to estimate farm production of infectious lice stages. Furthermore, we use an empirical estimate of the relative risk of salmon lice transmission between farms, that depend on inter-farm distances, to estimate the external infection pressure at a farm site, i.e. the infection pressure from infective salmon lice of neighbouring farm origin. Finally, we test whether our estimates of infection pressure from neighbouring farms as well as internal within farm infection pressure, predicts subsequent development of infection in cohorts of farmed salmonids in their initial phase of marine production. We find that estimated external infection pressure is a main predictor of salmon lice population dynamics in newly stocked cohorts of salmonids. Our results emphasize the importance of keeping the production of infectious lice stages at low levels within local networks of salmon farms. Our model can easily be implemented for real time estimation of infection pressure at the national scale, utilizing the masses of data generated through the compulsory lice monitoring in salmon farms. The implementation of such a system should give the salmon industry greater predictability with respect to salmon lice infection levels, and aid the decision making process when the development of new farm sites are planned.

  19. The effect of siesta in parameters of cardiac structure and in interpretation of ambulatory arterial blood pressure monitoring

    Directory of Open Access Journals (Sweden)

    Marco A.M. Gomes

    2000-04-01

    Full Text Available OBJECTIVE: To evaluate the influence of the siesta in ambulatory blood pressure (BP monitoring and in cardiac structure parameters. METHODS: 1940 ambulatory arterial blood pressure monitoring tests were analyzed (Spacelabs 90207, 15/15 minutes from 7:00 to 22:00 hours and 20/20 minutes from 22:01 to 6.59hours and 21% of the records indicated that the person had taken a siesta (263 woman, 52±14 years. The average duration of the siesta was 118±58 minutes. RESULTS: (average ± standard deviation The average of systolic/diastolic pressures during wakefulness, including the napping period, was less than the average for the period not including the siesta (138±16/85±11 vs 139±16/86±11 mmHg, p5%. CONCLUSION: The siesta influenced the heart structure parameters and from a statistical point of view the average of systolic and diastolic pressures and the respective pressure loads of the wakeful period.

  20. COMPUTATIONAL INVESTIGATION ON CSF FLOW ANALYSIS IN THE THIRD VENTRICLE AND AQUEDUCT OF SYLVIUS

    Directory of Open Access Journals (Sweden)

    Edi Azali Hadzri

    2011-12-01

    Full Text Available In this study, a three dimensional (3D model of the third ventricle and aqueduct of Sylvius derived from MRI scans was constructed by using Computational Fluid Dynamics (CFD modeling. Cerebrospinal fluid(CSF can be modeled as a Newtonian Fluid and its flow through the region of interest (ROI was visualized using Engineering Fluid Dynamics (EFD.The constructed ROI was regarded as rigid walled and only steady state flow was able to be defined due to the limitations of current software. Different flow rate was simulated at the Foramen of Monro and a small stenosis was modeled at the middle of the aqueduct of Sylvius at a fixed location. This was made corresponding to normal patients with variation of CSF flow rate physiologically and abnormal patients with tumor causing obstruction to or within the aqueduct of Sylvius, respectively. Due to the small dimensions of the ROI geometry, gravity and complex external gravity that acted upon it was considered to be neglected. The results show as the flow rate increase, the pressure drop of CSF in the ROI proportionally increased. For normal CSF flow rate, the presence of stenosis in the aqueduct demonstrates a significant increased pressure drop.ABSTRAK-Dalam kajian ini, model tiga dimensi (3D untuk ventrikel ketiga dan akueduk Sylvius, yang terhasil daripada pengimejan resonans magnetik telah dikonstruksi menggunakan Permodelan Perkomputeran Dinamik Bendalir (Computational Fluid Dynamics (CFD. Cecair serebrospinal (Cerebrospinal fluid (CSF dimodelkan sebagai bendalir Newtonan dan alirannya melalui kawasan kepentingan (region of interest (ROI digambarkan menggunakan Dinamik Bendalir Kejuruteraan (Engineering Fluid Dynamics (EFD. Kawasan kepentingan yang dikonstruksi dianggap sebagai dinding tegar dan hanya aliran keadaan tunak yang dapat ditakrifkan berdasarkan pengehadan perisian komputer terkini. Kadar aliran yang berbeza disimulasikan di foramen monro dan laluan stenosis yang kecil dimodelkan di tengah

  1. Fiberoptic intraparenchymal brain pressure monitoring with the Camino V420 monitor: reflections on our experience in 163 severely head-injured patients.

    Science.gov (United States)

    Poca, Maria-Antonia; Sahuquillo, Juan; Arribas, Mercedes; Báguena, Marcelino; Amorós, Sonia; Rubio, Enrique

    2002-04-01

    To assess the safety and accuracy of the Camino intraparenchymal sensor, we prospectively evaluated hemorrhagic complications, zero-drift, infection, and system malfunction in 163 patients monitored after a severe head injury. Mean duration of intracranial pressure (ICP) monitoring was 5 +/- 2.2 days (range: 12 h to 11 days). Of the 141 patients with a control CT scan, four showed a 1-2-cc collection of blood at the catheter's end. When removed, the sensors underread the true ICP value (negative zero-drift) in 80 of the 126 sensors evaluated (63.5%). Fourteen sensors showed no zero-drift, and 32 sensors overread the true ICP value (positive zero-drift) (median: -1 mm Hg; interquartile range: -4 to +1 mm Hg). No significant relationship was found between zero-drift, the surgeon who implanted the sensor, intracranial hypertension, or duration of ICP monitoring. No clinical infections could be attributed to the devices. Sixteen patients (9.8%) required more than one ICP sensor due to malfunctioning of the system. In conclusion, continuous ICP monitoring using the Camino intraparenchymal sensor has a low complication rate. However, this sensor may underread the real ICP values in a high number of patients. The lack of correlation between duration of ICP monitoring and zero-drift suggests that, contrary to the recommendations of other reports, the intraparenchymatous Camino sensor can provide reliable readings after the fifth day of use.

  2. Basis of monitoring central blood pressure and hemodynamic parameters by peripheral arterial pulse waveform analyses.

    Science.gov (United States)

    Miyashita, Hiroshi; Katsuda, Shin-ichiro

    2013-01-01

    In hypertension clinics, central blood pressure (CBP) should be estimated, instead of directly measured, by the "signal processing" of a noninvasive peripheral pressure waveform. This paper deals with the data obtained in our three separate studies focusing on a major estimation method, i.e., radial artery late systolic shoulder pressure (rSBP2)-based CBP estimation. Study 1: Using a wave separation analysis of precise animal data of pressure wave transmission along the upper-limb arteries, we first demonstrate that pulse pressure amplification is largely attributable to local wave reflection alone. Study 2: A frequency component analysis of simultaneously recorded human central and radial artery pressure waveforms showed a predominance of lower (1st+2nd) harmonic components in determining the central augmentation peak amplitude. The features of a central pressure waveform, including its phase property, may contribute to the less-altered transmission of augmentation peak pressure to rSBP2. Study 3: Comparisons of noninvasive rSBP2 with direct or estimated central systolic blood pressure (cSBP) revealed broad agreement but also augmentation-dependent biases. Based on the features of the biases as well as the counterbalanced relationship between pulse pressure amplification and the transmission-induced alterations of augmentation peak amplitude observed in Study 2, we propose an improved cSBP estimate, SBPm, the simple arithmetic mean of rSBP2 and peripheral systolic blood pressure.

  3. The Camino intracranial pressure sensor: is it optimal technology? An internal audit with a review of current intracranial pressure monitoring technologies.

    Science.gov (United States)

    Piper, I; Barnes, A; Smith, D; Dunn, L

    2001-11-01

    To audit the reliability of the Camino intracranial pressure (ICP) sensor (Camino Laboratories, San Diego, CA) in our clinical practice as part of a continuing quality assurance program, and to assess its relative usefulness as compared with currently available ICP monitoring technologies that we reviewed. Prospective audit of ICP device reliability and function in 50 patients with head injuries. Zero drift was recorded immediately after the ICP device was removed from the patient. Dynamic frequency response bench testing of each functioning catheter from 0 to 30 Hz and static calibration testing from 0 to 100 mmHg during environmental temperature variation from 22 to 40 degrees C were carried out. Zero drift (range, -13 to 22 mmHg; median, -1 mmHg) was recorded immediately after the devices were removed from patients. Seventeen (50%) of the devices tested for zero drift had absolute drifts of at least 3 mmHg. There was no correlation between recorded zero drift and duration of monitoring (r = 0.154, P = 0.207). Five sensors (10% of those tested) failed during patient monitoring and were replaced. Static and dynamic calibration tests of the functioning sensors were within the manufacturer's specifications. However, the sensitivity of the devices to environmental temperature remains a problem. The Camino ICP sensor remains one of the most popular ICP monitoring devices for use in patients with traumatic brain injuries. However, our recent in-house assessment demonstrated the robustness of the device to be less than adequate during routine practice. In this study, more than 50% exhibited zero drift greater than 3 mmHg, which is unacceptable in a catheter tip ICP monitoring device in which zero drift and calibration cannot be checked in vivo. A review of the literature revealed that other available ICP monitoring devices may prove to be more reliable and thus more appropriate for routine clinical measurement of ICP.

  4. Comparison of non-invasive blood pressure monitoring using modified arterial applanation tonometry with intra-arterial measurement.

    Science.gov (United States)

    Harju, Jarkko; Vehkaoja, Antti; Kumpulainen, Pekka; Campadello, Stefano; Lindroos, Ville; Yli-Hankala, Arvi; Oksala, Niku

    2017-01-19

    Intermittent non-invasive blood pressure measurement with tourniquets is slow, can cause nerve and skin damage, and interferes with other measurements. Invasive measurement cannot be safely used in all conditions. Modified arterial tonometry may be an alternative for fast and continuous measurement. Our aim was to compare arterial tonometry sensor (BPro(®)) with invasive blood pressure measurement to clarify whether it could be utilized in the postoperative setting. 28 patients who underwent elective surgery requiring arterial cannulation were analyzed. Patients were monitored post-operatively for 2 h with standard invasive monitoring and with a study device comprising an arterial tonometry sensor (BPro(®)) added with a three-dimensional accelerometer to investigate the potential impact of movement. Recordings were collected electronically. The results revealed inaccurate readings in method comparison between the devices based on recommendations by Association for the Advancement of Medical Instrumentation (AAMI). On a Bland-Altman plot, the bias and precision between these two methods was 19.8 ± 16.7 (Limits of agreement - 20.1 to 59.6) mmHg, Spearman correlation coefficient r = 0.61. For diastolic pressure, the difference was 4.8 ± 7.7 (LoA - 14.1 to 23.6) mmHg (r = 0.72), and for mean arterial pressure it was 11.18 ± 11.1 (LoA - 12.1 to 34.2) mmHg (r = 0.642). Our study revealed inaccurate agreement (AAMI) between the two methods when measuring systolic and mean blood pressures during post-operative care. The readings for diastolic pressures were inside the limits recommended by AAMI. Movement increased the failure rate significantly (p arterial tonometry is not an appropriate replacement for invasive blood pressure measurement in these patients.

  5. Effect of environmental exposure to cigarette smoke on blood pressure in 24‑hour ambulatory blood pressure monitoring in patients with essential hypertension.

    Science.gov (United States)

    Gać, Paweł; Poręba, Rafał; Poręba, Małgorzata; Mazur, Grzegorz; Sobieszczańska, Małgorzata

    2014-01-01

    A relationship between environmental exposure to cigarette smoke and blood pressure has not been well‑established. The aim of the study was to evaluate the effects of environmental exposure to cigarette smoke on blood pressure (BP) in patients with essential hypertension. The study involved 39 nonsmoking patients with essential hypertension treated with hypotensive agents and environmentally exposed to cigarette smoke (group 1) and 39 nonsmoking patients with essential hypertension treated with hypotensive agents and not exposed to cigarette smoke (group 2). The following variables of 24‑hour ambulatory BP monitoring (ABPM) were measured: systolic BP (SBP), diastolic BP (DBP), mean arterial pressure (MAP), and pulse pressure (PP) during 24‑hour ABPM, and, separately, for the period of daily activity and night rest. In group 1, the mean values of 24‑hour SBP, DBP, MAP, and PP, daytime SBP, DBP, MAP, and PP, and nighttime SBP, MAP, and PP were significantly higher than those in group 2. Statistically significant positive linear correlations were demonstrated between the mean time of daily exposure (expressed in hours) to cigarette smoke and 24‑hour MAP and PP (r = 0.52 and r = 0.48, respectively, P environmental exposure to cigarette smoke were independent factors of elevated 24‑hour PP in the study group. In patients with essential hypertension, environmental exposure to cigarette smoke may result in elevated BP values in 24‑hour ABPM.

  6. Comparison of Continuous Noninvasive Blood Pressure Monitoring by TL-300 With Standard Invasive Blood Pressure Measurement in Patients Undergoing Elective Neurosurgery.

    Science.gov (United States)

    Lin, Wen-Qian; Wu, Huang-Hui; Su, Chang-Sheng; Yang, Jian-Teng; Xiao, Jin-Rong; Cai, Yu-Ping; Wu, Xiao-Zhi; Chen, Guo-Zhong

    2017-01-01

    Intraoperative blood pressure (BP) is one of the basic vital signs monitoring. Compared with standard invasive BP measurement, TL-300 allows for a continuous and beat-to-beat noninvasive intraoperative BP monitoring. The current retrospective study compared the accuracy and precision of this noninvasive technique for continuous BP monitoring with that of standard invasive BP measurement in patients undergoing elective neurosurgery. BP records of 23 patients undergoing elective neurosurgery, measured by both noninvasive TL-300 and invasive radial arterial catheter method, were retrospectively analyzed. Variability in BP data was analyzed by using linear regressions and Bland-Altman analysis. Four thousand three hundred eighty-one pairs of BP measurements from a total of 23 patients were included. The coefficient of determination of systolic, diastolic, and mean BP were 0.908, 0.803, and 0.922, respectively. And their bias was found to be 1.3±5.87 mm Hg (95% limits of agreement: -10.2 to +12.8 mm Hg), 2.8±6.40 mm Hg (95% limits of agreement: -9.8 to +15.3 mm Hg), and 1.8±4.20 mm Hg (95% limits of agreement: -6.4 to +10.1 mm Hg), respectively. TL-300 system is a promising noninvasive alternative to the invasive arterial catheter method for intraoperative BP monitoring, with a high accuracy and precision. With the limitation of the current retrospective study, further prospective method comparison studies are needed.

  7. Significance Of 30 KD Protein As A Diagnostic Marker In CSF Of tuberculour Meningits

    Directory of Open Access Journals (Sweden)

    Kashyap R.S

    2001-01-01

    Full Text Available Tuberculous meningitis (TBM is a sub acute or chronic inflammation of the cerebral meninges caused by tubercule bacilli, the diagnosis for which is still very intricate. To establish a rapid diagnosis, we used Sodium dodecyl suplhate polyacrylamide gel electrophoresis (SDS-PAGE for the detection of marker protein in CSF specific to TBM patients. CSF was collected by standard lumbar puncture technique. Polyclonal antibody was raised against sonicated M.tuberculosis of H37RV in rabbit. 145 CSF samples were collected for this study over a period of two and half years which included 44 suspected and one proven case of TBM. In this communication we have investigated for a possible presence of a marker protein(s in cerebrospinal fluid (CSF of TBM patients. Two bands, a 30kd and a 14kd were detected. The 30kd band was observed in 92% cases of TBM patients. The 14kd band was not much of diagnostic importance since it was found in only about 45%. None of the control group patients had these protein bands. The 30 kd protein band either disappeared or became faint on anti-TB medication. To evaluate whether the eluted 30 kd protein was a mycobacterium tuberculosis product, gel retardation assay was also performed. The 30kd protein did not react with the polyclonal antisera. The CSF biochemical picture correlated well with the presence of this protein band. This study suggests that 30kd protein band observed in CSF is not a Mycobacterium product and is not only an important diagnostic marker for early diagnosis of TBM but may also be useful for monitoring the post treatment phase.

  8. Neurological assessment and its relationship to CSF biomarkers in amateur boxers.

    Directory of Open Access Journals (Sweden)

    Sanna Neselius

    Full Text Available BACKGROUND: Mild traumatic brain injury (TBI or concussion is common in many sports. Today, neuropsychological evaluation is recommended in the monitoring of a concussion and in return-to-play considerations. To investigate the sensitivity of neuropsychological assessment, we tested amateur boxers post bout and compared with controls. Further the relationship between neuropsychological test results and brain injury biomarkers in the cerebrospinal fluid (CSF were investigated. METHOD: Thirty amateur boxers on high elite level with a minimum of 45 bouts and 25 non-boxing matched controls were included. Memory tests (Rey Osterrieth Complex Figure, Listening Span, Digit Span, Controlled Word Association Test, and computerized testing of episodic memory, tests of processing speed and executive functions (Trail Making, Reaction Time, and Finger Tapping were performed and related to previously published CSF biomarker results for the axonal injury marker neurofilament light (NFL. RESULTS: The neurological assessment showed no significant differences between boxers and controls, although elevated CSF NFL, as a sign of axonal injury, was detected in about 80% of the boxers 1-6 days post bout. The investigation of the relationship between neuropsychological evaluation and CSF NFL concentrations revealed that boxers with persisting NFL concentration elevation after at least 14 days resting time post bout, had a significantly poorer performance on Trail Making A (p = 0.041 and Simple Reaction Time (p = 0.042 compared to other boxers. CONCLUSION: This is the first study showing traumatic axonal brain injury can be present without measureable cognitive impairment. The repetitive, subconcussive head trauma in amateur boxing causes axonal injury that can be detected with analysis of CSF NFL, but is not sufficient to produce impairment in memory tests, tests of processing speed, or executive functions. The association of prolonged CSF NFL increase in

  9. Monitoring Rates and Heterogeneity of High-Pressure Germination of Bacillus Spores by Phase-Contrast Microscopy of Individual Spores

    Science.gov (United States)

    2014-01-01

    SECURITY CLASSIFICATION OF: The germination of multiple individual Bacillus subtilis spores by a high pressure (HP) of 140-150 (unless noted...otherwise) megaPascals (MPa) that activates spore germinant receptors (GRs) was monitored by phase contrast microscopy in a diamond anvil cell. Major...conclusions were that: i) >95% of spores germinated in 40 min; ii) individual spore’s HP germination kinetics were very similar to those for nutrient

  10. Rationale and methodology of monitoring ambulatory blood pressure and arterial compliance in the Hypertension in the Very Elderly Trial

    OpenAIRE

    2006-01-01

    OBJECTIVE: This article describes the rationale and methodology for the monitoring of ambulatory blood pressure and arterial compliance in hypertensive patients aged 80 years and above. This is a side project of the Hypertension in the Very Elderly Trial. METHODS: The hypertension in the Very Elderly Trial is a multicentre, double-blind, randomized, placebo-controlled trial aiming to investigate the effect of active treatment on cardiovascular and other outcomes in hypertensive patients aged ...

  11. Monitoring intracranial pressure utilizing a novel pattern of brain multiparameters in the treatment of severe traumatic brain injury

    Directory of Open Access Journals (Sweden)

    Sun H

    2016-06-01

    Full Text Available Hong-tao Sun,1,* Maohua Zheng,2,* Yanmin Wang,1 Yunfeng Diao,1 Wanyong Zhao,1 Zhengjun Wei1 1Sixth Department of Neurosurgery, Affiliated Hospital of Logistics University of People’s Armed Police Force, Tianjin, 2Department of Neurosurgery, The First Hospital of Lanzhou University, Lanzhou, People’s Republic of China *These authors contributed equally to this work Abstract: The aim of the study was to evaluate the clinical value of multiple brain parameters on monitoring intracranial pressure (ICP procedures in the therapy of severe traumatic brain injury (sTBI utilizing mild hypothermia treatment (MHT alone or a combination strategy with other therapeutic techniques. A total of 62 patients with sTBI (Glasgow Coma Scale score <8 were treated using mild hypothermia alone or mild hypothermia combined with conventional ICP procedures such as dehydration using mannitol, hyperventilation, and decompressive craniectomy. The multiple brain parameters, which included ICP, cerebral perfusion pressure, transcranial Doppler, brain tissue partial pressure of oxygen, and jugular venous oxygen saturation, were detected and analyzed. All of these measures can control the ICP of sTBI patients to a certain extent, but multiparameters associated with brain environment and functions have to be critically monitored simultaneously because some procedures of reducing ICP can cause side effects for long-term recovery in sTBI patients. The result suggested that multimodality monitoring must be performed during the process of mild hypothermia combined with conventional ICP procedures in order to safely target different clinical methods to specific patients who may benefit from an individual therapy. Keywords: mild hypothermia treatment, cerebral perfusion pressure, brain tissue partial pressure of oxygen

  12. [Realization of mobile phone based wireless blood pressure monitoring system and its preliminary implementation].

    Science.gov (United States)

    Wang, Shuo; Gong, Eenhao; Yu, Yang; Liu, Jing

    2011-11-01

    A novel system which could measure blood pressure wirelessly through mobile phone has been proposed and developed. It consisted of a blood pressure signal recorder based on MCU (Micro Control Unit), which could transmit measured data via Bluetooth, and a software embedded on mobile phone, which could calculate the value of blood pressure and the rate of heart beat. The measurement results could easily be stored in text documents or in picture format. Detailed scheme and design of each module in the system was illustrated and experiments were conducted to demonstrate the reliability and stability of the device. A series of new conceptual explorations into blood pressure related issues were conducted with this system, including the variational blood pressure at different time periods in a day, the effect of posture on the measurement results and the impact of movements on blood pressure.

  13. The design and application of an inexpensive pressure monitoring system for shallow water level measurement, tensiometry and piezometry

    Science.gov (United States)

    Greswell, Richard; Ellis, Paul; Cuthbert, Mark; White, Rachel; Durand, Véronique

    2009-07-01

    SummaryThe measurement of water level or pressure is often a key requirement in the study of hydrogeological, hydrological and soil science processes. Modern microelectronics can provide a range of solutions for the automated monitoring of water levels in boreholes, rivers as well as more specialised applications such as tensiometry. The advantages of stand-alone monitoring systems when compared to manual measurement approaches are well understood, especially when the point of measurement is remote or the frequency of perturbation is rapid. For this reason the combination of a pressure transducer and logging system within a single package has been widely adopted in commercially available systems. However, although the price of these devices continues to fall, they may still represent a significant cost for researchers on limited budgets. We therefore present a design for a simple, inexpensive (˜£30) but versatile pressure monitoring system which can interface to low-cost (£50-£70) data-loggers. We demonstrate how the design may be adapted for a range of field applications which include: river level measurements, tensiometers, permeameters and in situ river-bed piezometers. The performance of the system is assessed and for each application the specific design and examples of resulting data are described.

  14. Exploring the efficacy of endoscopic ventriculostomy for hydrocephalus treatment via a multicompartmental poroelastic model of CSF transport: a computational perspective.

    Directory of Open Access Journals (Sweden)

    John C Vardakis

    Full Text Available This study proposes the implementation of a Multiple-Network Poroelastic Theory (MPET model coupled with finite-volume computational fluid dynamics for the purpose of studying, in detail, the effects of obstructing CSF transport within an anatomically accurate cerebral environment. The MPET representation allows the investigation of fluid transport between CSF, brain parenchyma and cerebral blood, in an integral and comprehensive manner. A key novelty in the model is the amalgamation of anatomically accurate choroid plexuses with their feeding arteries and a simple relationship relaxing the constraint of a unique permeability for the CSF compartment. This was done in order to account for the Aquaporin-4-mediated swelling characteristics. The aim of this varying permeability compartment was to bring to light a feedback mechanism that could counteract the effects of ventricular dilation and subsequent elevations of CSF pressure through the efflux of excess CSF into the blood system. This model is used to demonstrate the impact of aqueductal stenosis and fourth ventricle outlet obstruction (FVOO. The implications of treating such a clinical condition with the aid of endoscopic third (ETV and endoscopic fourth (EFV ventriculostomy are considered. We observed peak CSF velocities in the aqueduct of the order of 15.6 cm/s in the healthy case, 45.4 cm/s and 72.8 cm/s for the mild and severe cases respectively. The application of ETV reduced the aqueductal velocity to levels around 16-17 cm/s. Ventricular displacement, CSF pressure, wall shear stress (WSS and pressure difference between lateral and fourth ventricles (ΔP increased with applied stenosis, and subsequently dropped to nominal levels with the application of ETV. The greatest reversal of the effects of atresia come by opting for ETV rather than the more complicated procedure of EFV.

  15. Ambulatory instrument for monitoring indirect beat-to-beat blood pressure in superficial temporal artery using volume-compensation method.

    Science.gov (United States)

    Tanaka, S; Yamakoshi, K

    1996-11-01

    A portable instrument, based on a volume-compensation technique, is designed for ambulatory monitoring of indirect beat-to-beat blood pressure (BP) in the superficial temporal artery. The instrument consists of a small disc-type cuff and a portable unit carried by the subject. Several components are integrated in the cuff for applying counter-pressure to the artery, i.e. a reflectance-type photo-plethysmographic sensor for arterial volume detection, a pressure sensor for cuff pressure Pc measurement and a nozzle flapper-type- electro-pneumatic convertor for controlling Pc. The portable unit includes volume servo control circuitry and a microprocessor-based signal-processing and recording unit. This automatically performs all the necessary measurement procedures and stores into a memory IC element the processed systolic, mean and diastolic blood pressure data, together with pulse intervals on a beat-to-beat basis from the servo-controlled Pc (indirectly measured BP waveform). With this instrument, momentary changes in BP during ambulatory situations such as bicycle ergometer exercise and daily activities including motorway driving are successfully recorded. From the results of simultaneous measurement of the subject's posture changes, the effect of posture change on blood pressure, e.g. baroreceptor-cardiac reflex, is also clearly demonstrated.

  16. Wireless, Ultra-Low-Power Implantable Sensor for Chronic Bladder Pressure Monitoring

    OpenAIRE

    Majerus, Steve J. A.; GARVERICK, STEVEN L.; SUSTER, MICHAEL A.; FLETTER, PAUL C.; Damaser, Margot S.

    2012-01-01

    The wireless implantable/intracavity micromanometer (WIMM) system was designed to fulfill the unmet need for a chronic bladder pressure sensing device in urological fields such as urodynamics for diagnosis and neuromodulation for bladder control. Neuromodulation in particular would benefit from a wireless bladder pressure sensor which could provide real-time pressure feedback to an implanted stimulator, resulting in greater bladder capacity while using less power. The WIMM uses custom integra...

  17. The impact of continuous non-invasive arterial blood pressure monitoring on blood pressure stability during general anaesthesia in orthopaedic patients: A randomised trial.

    Science.gov (United States)

    Meidert, Agnes S; Nold, Johanna S; Hornung, Roman; Paulus, Alexander C; Zwißler, Bernhard; Czerner, Stephan

    2017-11-01

    In patients undergoing general anaesthesia, intraoperative hypotension occurs frequently and is associated with adverse outcomes such as postoperative acute kidney failure, myocardial infarction or stroke. A history of chronic hypertension renders patients more susceptible to a decrease in blood pressure (BP) after induction of general anaesthesia. As a patient's BP is generally monitored intermittently via an upper arm cuff, there may be a delay in the detection of hypotension by the anaesthetist. The current study investigates whether the presence of continuous BP monitoring leads to improved BP stability. Randomised, controlled and single-centre study. A total of 160 orthopaedic patients undergoing general anaesthesia with a history of chronic hypertension. The patients were randomised to either a study group (n = 77) that received continuous non-invasive BP monitoring in addition to oscillometric intermittent monitoring, or a control group (n = 83) whose BP was monitored intermittently only. The interval for oscillometric measurements in both groups was set to 3 min. After induction of general anaesthesia, oscillometric BP values of the two groups were compared for the first hour of the procedure. Anaesthetists were blinded to the purpose of the study. BP stability and hypotensive events. There was no difference in baseline BP between the groups. After adjustment for multiple testing, mean arterial BP in the study group was significantly higher than in the control group at 12 and 15 min. Mean ± SD for study and control group, respectively were: 12 min, 102 ± 24 vs. 90 ± 26 mmHg (P = 0.039) and 15 min, 102 ± 21 vs. 90 ± 23 mmHg (P = 0.023). Hypotensive readings below a mean pressure of 55 mmHg occurred more often in the control group (25 vs. 7, P = 0.047). Continuous monitoring contributes to BP stability in the studied population. NCT02519101.

  18. Tracheal tube and laryngeal mask cuff pressure during anaesthesia - mandatory monitoring is in need

    Directory of Open Access Journals (Sweden)

    Møller Ann M

    2010-12-01

    Full Text Available Abstract Background To prevent endothelium and nerve lesions, tracheal tube and laryngeal mask cuff pressure is to be maintained at a low level and yet be high enough to secure air sealing. Method In a prospective quality-control study, 201 patients undergoing surgery during anaesthesia (without the use of nitrous oxide were included for determination of the cuff pressure of the tracheal tubes and laryngeal masks. Results In the 119 patients provided with a tracheal tube, the median cuff pressure was 30 (range 8 - 100 cm H2O and the pressure exceeded 30 cm H2O (upper recommended level for 54 patients. In the 82 patients provided with a laryngeal mask, the cuff pressure was 95 (10 - 121 cm H2O and above 60 cm H2O (upper recommended level for 56 patients and in 34 of these patients, the pressure exceeded the upper cuff gauge limit (120 cm H2O. There was no association between cuff pressure and age, body mass index, type of surgery, or time from induction of anaesthesia to the time the cuff pressure was measured. Conclusion For maintenance of epithelia flow and nerve function and at the same time secure air sealing, this evaluation indicates that the cuff pressure needs to be checked as part of the procedures involved in induction of anaesthesia and eventually checked during surgery.

  19. [Arterial hypertension and control in Brazzaville (Congo): role of ambulatory blood pressure monitoring (ABPM)].

    Science.gov (United States)

    Ikama, M S; Nsitou, B M; Makani, J; Nkalla-Lambi, M; Passi-Louamba, C

    2015-04-01

    To evaluate the rate control in the hypertensive patients and to identify the predictive factors of non-control. It was about a cross-sectional study with prospective collection of data over a period of 36 months. It has been held in Brazzaville, and included a consecutive series of 620 hypertensive patients known and treated for at least 6 weeks, having profited from an ambulatory blood pressure monitoring (ABPM) with therapeutic aiming. We used the TONOPORT V and the software Cardiosoft 6.51 of GE Health Care, respectively for the recording and the data analysis. The threshold fixed on the average of 24-hour was BP<130/80 mmHg, and the patients divided into two groups according to whether they were or not controlled. They were 352 men (56.8%) and 268 women (43.2%), old on average of 53.8 ± 9.7 years (ranges: 29 and 89 years). The standard of living of the patients was average in 330 cases (53.2%), weak in 132 cases (21.3%), and high in 71 cases (11.5%). The other associated risk factors were sedentariness in 275 cases (44.4%), overweight/obesity in 134 cases (21.6%), dyslipidemia in 121 cases (19.5%), diabetes mellitus in 90 cases (14.5%), and tobacco addiction in 25 cases (4%). The hypertension, old of 5.8 ± 5.7 years on average, was controlled among 215 patients (34.7%). The 24- hour BP average was 139 ± 14 mmHg for the SBP and 88.2 ± 10.2 mmHg for the DBP. The awake and asleep BP averages were respectively 141 ± 14 mmHg and 133 ± 16.2 mmHg for the SBP, 90.5 ± 10.5 and 81.2 ± 11.1 mmHg for the DBP. The antihypertensive protocol used was a monotherapy in 130 cases (21%), bitherapy in 287 cases (46.3%), tritherapy in 154 cases (24.8%), quadritherapy or more in 27 cases (4.3%). Prevalence of non-dipping was 43%. Age and male gender were the significant predictors of poor control. The rate control of hypertension in our study population remains low. Its improvement passes by the education of the hypertensive patients and the improvement of their living

  20. Assessment of the usability of a digital learning technology prototype for monitoring intracranial pressure.

    Science.gov (United States)

    Carvalho, Lilian Regina de; Évora, Yolanda Dora Martinez; Zem-Mascarenhas, Silvia Helena

    2016-08-29

    to assess the usability of a digital learning technology prototype as a new method for minimally invasive monitoring of intracranial pressure. descriptive study using a quantitative approach on assessing the usability of a prototype based on Nielsen's ten heuristics. Four experts in the area of Human-Computer interaction participated in the study. the evaluation delivered eight violated heuristics and 31 usability problems in the 32 screens of the prototype. the suggestions of the evaluators were critical for developing an intuitive, user-friendly interface and will be included in the final version of the digital learning technology. avaliar a usabilidade de um protótipo educacional digital sobre um novo método para monitoração da pressão intracraniana de forma minimamente invasivo para enfermeiros e médicos. estudo descritivo com abordagem quantitativa sobre a avaliação de usabilidade de um protótipo com base nas dez Heurísticas de Nielsen. Participaram quatro especialistas da área de Interação Humano Computador. a avaliação resultou em oito heurísticas violadas e 31 problemas de usabilidade nas 32 telas do protótipo. as sugestões dos avaliadores foram cruciais para o desenvolvimento de uma interface amigável e intuitiva e serão consideradas na versão final da tecnologia educacional digital. evaluar la usabilidad de un prototipo educacional digital sobre un nuevo método para monitorización de la presión intracraneal, de manera mínimamente invasiva. estudio descriptivo con abordaje cuantitativo sobre la evaluación de usabilidad de un prototipo con base en las diez reglas Heurísticas de Nielsen. Participaron cuatro especialistas del área de Interacción Humana Computador. la evaluación resultó en ocho reglas heurísticas violadas y 31 problemas de usabilidad en las 32 pantallas del prototipo. las sugestiones de los evaluadores fueron cruciales para el desarrollo de una interfaz amigable e intuitiva y éstas serán consideradas en la

  1. Cerebrospinal fluid (CSF 25-hydroxyvitamin D concentration and CSF acetylcholinesterase activity are reduced in patients with Alzheimer's disease.

    Directory of Open Access Journals (Sweden)

    Per Johansson

    Full Text Available BACKGROUND: Little is known of vitamin D concentration in cerebrospinal fluid (CSF in Alzheimer's disease (AD and its relation with CSF acetylcholinesterase (AChE activity, a marker of cholinergic function. METHODS: A cross-sectional study of 52 consecutive patients under primary evaluation of cognitive impairment and 17 healthy controls. The patients had AD dementia or mild cognitive impairment (MCI diagnosed with AD dementia upon follow-up (n = 28, other dementias (n = 12, and stable MCI (SMCI, n = 12. We determined serum and CSF concentrations of calcium, parathyroid hormone (PTH, 25-hydroxyvitamin D (25OHD, and CSF activities of AChE and butyrylcholinesterase (BuChE. FINDINGS: CSF 25OHD level was reduced in AD patients (P < 0.05, and CSF AChE activity was decreased both in patients with AD (P < 0.05 and other dementias (P < 0.01 compared to healthy controls. None of the measured variables differed between BuChE K-variant genotypes whereas the participants that were homozygous in terms of the apolipoprotein E (APOE ε4 allele had decreased CSF AChE activity compared to subjects lacking the APOE ε4 allele (P = 0.01. In AD patients (n=28, CSF AChE activity correlated positively with CSF levels of total tau (T-tau (r = 0.44, P < 0.05 and phosphorylated tau protein (P-tau (r = 0.50, P < 0.01, but CSF activities of AChE or BuChE did not correlate with serum or CSF levels of 25OHD. CONCLUSIONS: In this pilot study, both CSF 25OHD level and CSF AChE activity were reduced in AD patients. However, the lack of correlations between 25OHD levels and CSF activities of AChE or BuChE might suggest different mechanisms of action, which could have implications for treatment trials.

  2. [Diagnostic potential of the lower-body negative pressure test in medical monitoring during extended space flights].

    Science.gov (United States)

    Aslferova, I V; Turchaninova, V F; Golubchikova, Z A; Krivolapov, V V; Khorosheva, E G

    2007-01-01

    To put into service the diagnostic and prognostic capabilities of the lower body negative pressure test (LBNP) during extended space flights, cardiovascular reactions associated with various levels of test tolerance were analyzed and compared. The article gives account of 60 tests performed by 44 cosmonauts 33 to 53 years of age during 59- to 415-d flights. In 36 tests tolerance was good and in 24 - satisfactory. Medical evaluation was fulfilled using GaMMa-1M, an onboard multifunctional medical monitoring system. Dynamics of ECG, blood pressure, stroke and minute volumes, pulse filling, and vertebral-basilar tone exhibited some specific traits that mirrored LBNP tolerance. Established were diagnostically implicative values in the course of pressure drop. Evidence was obtained that during the test and ensuing data analysis consideration should be given as to the span of changes of each parameter, so the time of their initiation, and dynamics.

  3. Post-exercise contractility, diastolic function, and pressure: Operator-independent sensor-based intelligent monitoring for heart failure telemedicine

    Directory of Open Access Journals (Sweden)

    Giannoni Massimo

    2009-05-01

    Full Text Available Abstract Background New sensors for intelligent remote monitoring of the heart should be developed. Recently, a cutaneous force-frequency relation recording system has been validated based on heart sound amplitude and timing variations at increasing heart rates. Aim To assess sensor-based post-exercise contractility, diastolic function and pressure in normal and diseased hearts as a model of a wireless telemedicine system. Methods We enrolled 150 patients and 22 controls referred for exercise-stress echocardiography, age 55 ± 18 years. The sensor was attached in the precordial region by an ECG electrode. Stress and recovery contractility were derived by first heart sound amplitude vibration changes; diastolic times were acquired continuously. Systemic pressure changes were quantitatively documented by second heart sound recording. Results Interpretable sensor recordings were obtained in all patients (feasibility = 100%. Post-exercise contractility overshoot (defined as increase > 10% of recovery contractility vs exercise value was more frequent in patients than controls (27% vs 8%, p 1 in 20 patients and in none of the controls (p 1 in only 3 patients (p Conclusion Post-exercise contractility, diastolic time and pressure changes can be continuously measured by a cutaneous sensor. Heart disease affects not only exercise systolic performance, but also post-exercise recovery, diastolic time intervals and blood pressure changes – in our study, all of these were monitored by a non-invasive wearable sensor.

  4. Perioperative use of bispectral (BIS) monitor for a pressure ulcer patient with locked-in syndrome (LIS).

    Science.gov (United States)

    Yoo, Christine; Ayello, Elizabeth A; Robins, Bryan; Salamanca, Victor R; Bloom, Marc J; Linton, Patrick; Brem, Harold; O'Neill, Daniel K

    2014-10-01

    The bispectral (BIS) monitor uses brain electroencephalographic data to measure the depth of sedation and pharmacological response during anaesthetic procedures. In this case, the BIS monitor was used for another purpose, to demonstrate postoperatively to the nursing staff that a patient with history of locked-in syndrome (LIS), who underwent pressure ulcer debridement, had periods of wakefulness and apparent sensation, even with his eyes closed. Furthermore, as patients with LIS can feel pain, despite being unable to move, local block or general anaesthesia should be provided for sharp surgical debridement and other painful procedures. This use of the BIS has shown that as a general rule, the staff should treat the patient as though he might be awake and sensate even if he does not open his eyes or move his limbs. The goal of this study was to continuously monitor pain level and communicate these findings to the entire wound team, i.e. anaesthesiologists, surgeons and nurses.

  5. Perioperative Use of Bispectral Monitor (BIS) for a Pressure Ulcer patient with Lock-In Syndrome (LIS)

    Science.gov (United States)

    Yoo, Christine; Ayello, Elizabeth A.; Robins, Bryan; Salamanca, Victor R.; Bloom, Marc J.; Linton, Patrick; Brem, Harold; O'Neill, Daniel K.

    2013-01-01

    The bispectral (BIS) monitor uses brain electroencephalographic data to measure depth of sedation and pharmacological response during anesthetic procedures. In this case, the BIS monitor was used for another purpose, to demonstrate postoperatively to the nursing staff that a patient with history of locked-in syndrome (LIS), who underwent pressure ulcer debridement, had periods of wakefulness and apparent sensation, even with his eyes closed. Furthermore, as patients with LIS can feel pain, despite being unable to move, local block or general anesthesia should be provided for sharp surgical debridement and other painful procedures. This use of the BIS has shown that as a general rule, the staff should treat the patient as though he might be awake and sensate even if he does not open his eyes or move his limbs. Our goal was to continuously monitor pain level and communicate these findings to the entire wound team, ie anesthesiologists, surgeons, and nurses. PMID:25252146

  6. Validation of the Oregon Scientific BPU 330 for self-monitoring of blood pressure according to the International Protocol

    Directory of Open Access Journals (Sweden)

    Li Li

    2008-10-01

    Full Text Available Li Li1, XinYu Zhang1, ChunHong Yan1, QingXiang Liang21Biomedical Engineering Lab, Faculty of Information Engineering, ShenZhen University, ShenZhen, China; 2Bao An People’s Hospital, ShenZhen, ChinaObjective: Extensive marketing of devices for self-measurement of blood pressure has created a need for purchasers to be able to satisfy themselves that such devices have been evaluated according to agreed criteria. The Oregon Scientific BPU 330 blood pressure monitor is an electronic device for upper arm measurement. This study assessed the accuracy of the Oregon Scientific BPU 330 blood pressure monitor according to the International Protocol by the Working Group on Blood Pressure Monitoring of the European Society of Hypertension for validation of blood pressure measuring devices.Method: 52 participants over 30 years of age were studied in the validation. Nine blood pressure measurements were taken alternately with a mercury sphygmomanometer by two observers, and by the supervisor, using the BPU 330 device. A total of 33 participants were selected for the analysis. The validation was divided into two phases. Phase 1 included 15 participants. If the device passed phase 1, 18 more participants were included. The 99 pairs of measurements were compared according to the International Protocol. The device was given a pass/fail recommendation based on its accuracy compared with the mercury standard (within 5, 10, and 15 mmHg, as well as the number met in the ranges specified by the International Protocol.Results: The mean and standard deviation of the difference between the mean of the observers and the BPU 330 device were 1.7 ± 4.7 mmHg and 2.8 ± 3.9 mmHg for systolic blood pressure (SBP and diastolic blood pressure (DBP, respectively. In phase 1, the device passed with a total of 33, 43, and 44 SBP readings; 38, 44, and 45 DBP readings were within 5, 10, and 15 mmHg, respectively. In phase 2.1, 81, 95, and 96 for SBP, and 83, 95, and 98 for DBP

  7. Fifteen years experience with finger arterial pressure monitoring : Assessment of the technology

    NARCIS (Netherlands)

    Imholz, B.P.M.; Wieling, W.; Montfrans, G.A. van; Wesseling, K.H.

    1998-01-01

    We review the Finapres technology, embodied in several TNO-prototypes and in the Ohmeda 2300 and 2300e Finapres NIBP. Finapres is an acronym for FINger Arterial PRESsure, the device delivers a continuous finger arterial pressure waveform. Many papers report on the accuracy of the device in compariso

  8. Systems and methods of monitoring acoustic pressure to detect a flame condition in a gas turbine

    Energy Technology Data Exchange (ETDEWEB)

    Ziminsky, Willy Steve (Simpsonville, SC); Krull, Anthony Wayne (Anderson, SC); Healy, Timothy Andrew (Simpsonville, SC), Yilmaz, Ertan (Glenville, NY)

    2011-05-17

    A method may detect a flashback condition in a fuel nozzle of a combustor. The method may include obtaining a current acoustic pressure signal from the combustor, analyzing the current acoustic pressure signal to determine current operating frequency information for the combustor, and indicating that the flashback condition exists based at least in part on the current operating frequency information.

  9. Fifteen years experience with finger arterial pressure monitoring : Assessment of the technology

    NARCIS (Netherlands)

    Imholz, B.P.M.; Wieling, W.; Montfrans, G.A. van; Wesseling, K.H.

    1998-01-01

    We review the Finapres technology, embodied in several TNO-prototypes and in the Ohmeda 2300 and 2300e Finapres NIBP. Finapres is an acronym for FINger Arterial PRESsure, the device delivers a continuous finger arterial pressure waveform. Many papers report on the accuracy of the device in

  10. [The design of plantar pressure distribution monitoring system and preliminary clinical application].

    Science.gov (United States)

    Zhu, Xianfeng; Zhao, Zilei; Xu, Donghao; Xu, Dongming

    2014-04-01

    Plantar pressure distribution can reflect the force of several key points on foot while standing and walking. A comprehensive understanding of the plantar pressure distribution makes great sense in the following aspects: the understanding of the normal foot biomechanics and function, clinical diagnosis, measurement of disease extent, postoperative efficacy evaluation, and rehabilitation research. A simple plantar pressure measurement device was designed in this study. This paper uses FlexiForce flexible sensor to pickup plantar pressure signal and USB A/D board to do data acquisition. The data are transferred into a laptop and processed by a VB-based software which can display, remember and replay the data. We chose patients with hallux valgus and normal people to measure the pressure distribution and make contrast analysis of plantar pressure with this device. It can be concluded that people with hallux valgus have higher pressure on the second metatarsophalangeal joint and the distribution move outward. The plantar pressure of patients postoperative could be greatly improved compared to the preoperative. The function of this device has been confirmed.

  11. Continuous Monitoring of Cerebrovascular Reactivity Using Pulse Waveform of Intracranial Pressure

    NARCIS (Netherlands)

    Aries, M.J.H.; Czosnyka, Marek; Budohoski, Karol P.; Kolias, Angelos G.; Radolovich, Danila K.; Lavinio, Andrea; Pickard, John D.; Smielewski, Peter

    2012-01-01

    Guidelines for the management of traumatic brain injury (TBI) call for the development of accurate methods for assessment of the relationship between cerebral perfusion pressure (CPP) and cerebral autoregulation and to determine the influence of quantitative indices of pressure autoregulation on out

  12. Self-monitoring of blood pressure in hypertension: A systematic review and individual patient data meta-analysis

    Science.gov (United States)

    Bosworth, Hayden B.; Bove, Alfred; Bray, Emma P.; Earle, Kenneth; Godwin, Marshall; Green, Beverly B.; Hebert, Paul; Kantola, Ilkka; Leiva, Alfonso; Mant, Jonathan; Margolis, Karen L.; McLaughlin, Mary Ann; Ogedegbe, Olugbenga; Qamar, Nashat; Varis, Juha; Verberk, Willem J.

    2017-01-01

    Background Self-monitoring of blood pressure (BP) appears to reduce BP in hypertension but important questions remain regarding effective implementation and which groups may benefit most. This individual patient data (IPD) meta-analysis was performed to better understand the effectiveness of BP self-monitoring to lower BP and control hypertension. Methods and findings Medline, Embase, and the Cochrane Library were searched for randomised trials comparing self-monitoring to no self-monitoring in hypertensive patients (June 2016). Two reviewers independently assessed articles for eligibility and the authors of eligible trials were approached requesting IPD. Of 2,846 articles in the initial search, 36 were eligible. IPD were provided from 25 trials, including 1 unpublished study. Data for the primary outcomes—change in mean clinic or ambulatory BP and proportion controlled below target at 12 months—were available from 15/19 possible studies (7,138/8,292 [86%] of randomised participants). Overall, self-monitoring was associated with reduced clinic systolic blood pressure (sBP) compared to usual care at 12 months (−3.2 mmHg, [95% CI −4.9, −1.6 mmHg]). However, this effect was strongly influenced by the intensity of co-intervention ranging from no effect with self-monitoring alone (−1.0 mmHg [−3.3, 1.2]), to a 6.1 mmHg (−9.0, −3.2) reduction when monitoring was combined with intensive support. Self-monitoring was most effective in those with fewer antihypertensive medications and higher baseline sBP up to 170 mmHg. No differences in efficacy were seen by sex or by most comorbidities. Ambulatory BP data at 12 months were available from 4 trials (1,478 patients), which assessed self-monitoring with little or no co-intervention. There was no association between self-monitoring and either lower clinic or ambulatory sBP in this group (clinic −0.2 mmHg [−2.2, 1.8]; ambulatory 1.1 mmHg [−0.3, 2.5]). Results for diastolic blood pressure (dBP) were similar

  13. Strict Blood Pressure Control Achieved Using an ICT-Based Home Blood Pressure Monitoring System in a Catastrophically Damaged Area After a Disaster.

    Science.gov (United States)

    Nishizawa, Masafumi; Hoshide, Satoshi; Okawara, Yukie; Matsuo, Takefumi; Kario, Kazuomi

    2017-01-01

    At the time of the Great East Japan earthquake and tsunami (March 2011), the authors developed a web-based information and communications technology (ICT)-based blood pressure (BP) monitoring system (the Disaster CArdiovascular Prevention [DCAP] Network) and introduced it in an area that was catastrophically damaged (Minamisanriku town) to help control the survivors' BP. Using this system, home BP (HBP) was monitored and the data were automatically transmitted to a central computer database and to the survivors' attending physicians. The study participants, 341 hypertensive patients, continued to use this system for 4 years after the disaster and all of the obtained HBP readings were analyzed. This DCAP HBP-guided approach helped achieve a decrease in the participants' HBPs (initial average: 151.3±20.0/86.9±10.2 mm Hg to 120.2±12.1/70.8±10.2 mm Hg) over the 4 years. In addition, the amplitude of seasonal BP variation was suppressed and the duration from the summer lowest HBP values to the winter peak HBP values was gradually prolonged. This ICT-based approach was useful to achieve strict HBP control and minimize the seasonal BP variation even in a catastrophically damaged area during a 4-year period after the disaster, suggesting that this approach could be a routine way to monitor BP in the community.

  14. Subsurface monitoring of reservoir pressure, temperature, relative humidity, and water content at the CAES Field Experiment, Pittsfield, Illinois: system design

    Energy Technology Data Exchange (ETDEWEB)

    Hostetler, D.D.; Childs, S.W.; Phillips, S.J.

    1983-03-01

    This subsurface-instrumentation design has been developed for the first Compressed Air Energy Storage (CAES) field experiment to be performed in porous media. Energy storage will be accomplished by alternating the injection and withdrawal of compressed air in a confined sandstone aquifer near Pittsfield, Illinois. The overall experiment objective is to characterize the reservoir's geochemical and thermohydraulic response to imposed CAES conditions. Specific experiment objectives require monitoring: air-bubble development; thermal development; cyclic pressure response; reservoir dehydration; and water coning. Supporting these objectives, four parameters will be continuously monitored at depth in the reservoir. They are: temperature; pressure; pore-air relative humidity; and pore-water content. Reservoir temperatures and pressures will range to maximum values approaching 200/sup 0/C and 300 psi, respectively. Both pore-air relative humidity and pore-water content will range from approx. 0 to 100%. This report discusses: instrumentation design; sensor and sensor system calibration; field installation and testing; and instrument-system operation. No comprehensive off-the-shelf instrument package exists to adequately monitor CAES reservoir parameters at depth. The best available sensors were selected and adapted for use under expected ranges of reservoir conditions. The instrumentation design criteria required: suitable sensor accuracy; continuous monitoring capability; redundancy; maximum sensor integrity; contingency planning; and minimum cost-information ratio. Three wells will be instrumented: the injection/withdrawal (I/W) well and the two instrument wells. Sensors will be deployed by wireline suspension in both open and backfilled (with sand) wellbores. The sensors deployed in the I/W well will be retrievable; the instrument-well sensors will not.

  15. Tracheal tube and laryngeal mask cuff pressure during anaesthesia - mandatory monitoring is in need

    DEFF Research Database (Denmark)

    Rokamp, K.Z.; Secher, N.H.; Møller, Ann;

    2010-01-01

    ABSTRACT: BACKGROUND: To prevent endothelium and nerve lesions, tracheal tube and laryngeal mask cuff pressure is to be maintained at a low level and yet be high enough to secure air sealing. METHOD: In a prospective quality-control study, 201 patients undergoing surgery during anaesthesia (without...... the use of nitrous oxide) were included for determination of the cuff pressure of the tracheal tubes and laryngeal masks. RESULTS: In the 119 patients provided with a tracheal tube, the median cuff pressure was 30 (range 8 - 100) cm H2O and the pressure exceeded 30 cm H2O (upper recommended level) for 54...... patients. In the 82 patients provided with a laryngeal mask, the cuff pressure was 95 (10 - 121) cm H2O and above 60 cm H2O (upper recommended level) for 56 patients and in 34 of these patients, the pressure exceeded the upper cuff gauge limit (120 cm H2O). There was no association between cuff pressure...

  16. Positive peer pressure: the effects of peer monitoring on children's disruptive behavior.

    Science.gov (United States)

    Carden Smith, L K; Fowler, S A

    1984-01-01

    Classroom peers can serve as powerful sources of reinforcement in increasing or maintaining both the positive and negative behaviors of their classmates. In two experiments, we examined the effectiveness of a peer-monitored token system on reducing disruption and nonparticipation during a transition period of a kindergarten class for behaviorally impaired children. Additionally, the effect of providing and subsequently withholding corrective feedback to peer mediators on the accuracy of their point awards was evaluated. Results in Experiment 1 suggest that both teacher- and peer-monitored interventions were successful in decreasing disruption and increasing participation of monitored peers. Experiment 2 further demonstrated that peer monitors could successfully initiate the token system without prior adult implementation. Analysis of the point awards in both experiments indicates that peer monitors consistently awarded points that were earned. However, when corrective feedback was withdrawn the peer monitors frequently awarded points that were not earned, i.e., they rarely withheld points for undesirable behavior. Even so, the monitored peers' disruptive behavior was maintained at low rates.

  17. Remote monitoring of blood pressure to reduce the risk of preeclampsia related complications with an innovative use of mobile technology.

    Science.gov (United States)

    Ganapathy, R; Grewal, A; Castleman, J S

    2016-10-01

    Assess suitability of remote self-monitoring of blood pressure with an innovative use of technology in detecting raised blood pressure in pregnancy. Assess ease of use and safety of the newly developed kit which included a Bluetooth enabled blood pressure machine and an android based mobile phone. The phone was modified to have only one application in it which showed the blood pressure readings with a traffic light system. The study was a proof of concept for wider use of the kit. We provided 50 women who were admitted with the kit. We assessed ease of use of the blood pressure machine and accuracy of readings including remote transfer to a computer. Technological feasibility and acceptance by women. The technology provides accurate data and visual cues including safe remote transfer instantaneously. 90% of the women agreed that the Kit was simple to use and 78% would prefer this model of testing at home. In a relatively resource rich setting the machine can reduce the number of patient visits for women who are at risk for preeclampsia. In resource poor settings it helps to triage resources to women who need it the most. It also is a valuable tool for research. Studies of the Kit in both developed and developing world will be needed to show reduction in perinatal and maternal morbidity or mortality secondary to preeclampsia. Copyright © 2016 International Society for the Study of Hypertension in Pregnancy. Published by Elsevier B.V. All rights reserved.

  18. Tracheal tube and laryngeal mask cuff pressure during anaesthesia - mandatory monitoring is in need

    DEFF Research Database (Denmark)

    Rokamp, K.Z.; Secher, N.H.; Møller, Ann

    2010-01-01

    ABSTRACT: BACKGROUND: To prevent endothelium and nerve lesions, tracheal tube and laryngeal mask cuff pressure is to be maintained at a low level and yet be high enough to secure air sealing. METHOD: In a prospective quality-control study, 201 patients undergoing surgery during anaesthesia (without...... and age, body mass index, type of surgery, or time from induction of anaesthesia to the time the cuff pressure was measured. CONCLUSION: For maintenance of epithelia flow and nerve function and at the same time secure air sealing, this evaluation indicates that the cuff pressure needs to be checked...

  19. Telemonitoring and/or self-monitoring of blood pressure in hypertension (TASMINH4): protocol for a randomised controlled trial.

    Science.gov (United States)

    Franssen, Marloes; Farmer, Andrew; Grant, Sabrina; Greenfield, Sheila; Heneghan, Carl; Hobbs, Richard; Hodgkinson, James; Jowett, Susan; Mant, Jonathan; Martin, Una; Milner, Siobhan; Monahan, Mark; Ogburn, Emma; Perera-Salazar, Rafael; Schwartz, Claire; Yu, Ly-Mee; McManus, Richard J

    2017-02-13

    Self-monitoring of hypertension is associated with lower systolic blood pressure (SBP). However, evidence for the use of self-monitoring to titrate antihypertensive medication by physicians is equivocal. Furthermore, there is some evidence for the efficacy of telemonitoring in the management of hypertension but it is not clear what this adds over and above self-monitoring. This trial aims to evaluate whether GP led antihypertensive titration using self-monitoring results in lower SBP compared to usual care and whether telemonitoring adds anything to self-monitoring alone. This will be a pragmatic primary care based, unblinded, randomised controlled trial of self-monitoring of BP with or without telemonitoring compared to usual care. Eligible patients will have poorly controlled hypertension (>140/90 mmHg) and will be recruited from primary care. Participants will be individually randomised to either usual care, self-monitoring alone, or self-monitoring with telemonitoring. The primary outcome of the trial will be difference in clinic SBP between intervention and control groups at 12 months adjusted for baseline SBP, gender, BP target and practice. At least 1110 patients will be sufficient to detect a difference in SBP between self-monitoring with or without telemonitoring and usual care of 5 mmHg with 90% power with an adjusted alpha of 0.017 (2-sided) to adjust for all three pairwise comparisons. Other outcomes will include adherence of anti-hypertensive medication, lifestyle behaviours, health-related quality of life, and adverse events. An economic analysis will consider both within trial costs and a model extrapolating the results thereafter. A qualitative sub study will gain insights into the views, experiences and decision making processes of patients and health care professionals focusing on the acceptability of self-monitoring and telemonitoring in the routine management of hypertension. The results of the trial will be directly applicable to primary

  20. Non-invasive continuous arterial pressure monitoring with Nexfin does not sufficiently replace invasive measurements in critically ill patients.

    Science.gov (United States)

    Hohn, A; Defosse, J M; Becker, S; Steffen, C; Wappler, F; Sakka, S G

    2013-08-01

    In this study, we tested the reliability of a non-invasive finger-cuff-based continuous arterial blood pressure monitoring device (Nexfin, BMEYE, Amsterdam, NL) in critically ill surgical patients. Invasive intra-arterial and non-invasive arterial pressure measurements from 25 patients during a 4-h period were compared at five time points. Correlation and linear regression analysis were used and mean bias, precision [sd of bias] and limits of agreement (LOA) [bias (2.0 sd)] were calculated using the Bland-Altman method. Eight data pairs were excluded because of error message from the non-invasive technique, and thus a total of 117 data pairs were analysed. Overall, correlation between mean arterial pressure (MAP) was r(2)=0.50. Bias, precision, and LOA between invasive and non-invasive MAP were 6 (12) and -18 to +30 mm Hg. In patients requiring norepinephrine (83 data pairs), correlation was r(2)=0.28 and bias, precision, and LOA were 6 (13) and -20 to +32 mm Hg, whereas in patients not receiving norepinephrine (34 data pairs) r(2) was 0.80 and mean bias, precision, and LOA were 6 (11) and -16 to +28 mm Hg. In patients with peripheral oedema (49 data pairs), r(2) was 0.40 and mean bias, precision and LOA were 7 (15) and -23 to +37 mm Hg. In patients without oedema (64 data pairs), r(2) was 0.66 and mean bias, precision, and LOA were 5 (9) and -13 to +23 mm Hg. Non-invasive blood pressure monitoring with Nexfin does not seem to be sufficiently accurate to replace intra-arterial invasive blood pressure measurements in critically ill patients.

  1. Clinical significance of ambulatory blood pressure monitoring%动态血压监测及其临床价值

    Institute of Scientific and Technical Information of China (English)

    孙乐; 于宪一

    2015-01-01

    Ambulatory blood pressure monitoring(ABPM)system can record patients blood pressure of 24 h on the predetermined time. The primary data forms the graph,the curve and the general report by operation of the related software after the analysis and statistics processing. Patients keep daily life condition,so the blood pressure data is more accuracy. ABPM can provide the dynamic change of the patients 24 h blood pressure,including the 24 h blood pressure survey data,the undulation situation and the change tendency. ABPM has become an useful element in the evaluation and follow - up of hypertension in adults. And ABPM is increasingly used to evaluate the blood pressure of children and adolescents in recent years. The ABPM has been shown to differ significantly values.%动态血压监测(ambulatory blood pressure monitoring,ABPM)是通过血压记录仪自动操作,在预定的时间点记录受检者日常生活状态下的血压,经相关的软件程序对原始数据进行分析和统计学处理后,形成图表、曲线和综合报告。ABPM 能提供24 h 血压测量数据、波动情况及变化趋势,能全面地反映患者24 h 血压的动态变化,近年来已经开始在儿科广泛应用,在高血压的诊断、治疗、预后评估及随访等多方面研究中均具有重要作用。

  2. Cost-benefit analysis of home blood pressure monitoring in hypertension diagnosis and treatment: an insurer perspective.

    Science.gov (United States)

    Arrieta, Alejandro; Woods, John R; Qiao, Nan; Jay, Stephen J

    2014-10-01

    Home blood pressure (BP) monitoring has been shown to be more effective than clinic BP monitoring for diagnosing and treating hypertension. However, reimbursement of home BP monitoring is uncommon in the United States because of a lack of evidence that it is cost beneficial for insurers. We develop a decision-analytic model, which we use to conduct a cost-benefit analysis from the perspective of the insurer. Model inputs are derived from the 2008 to 2011 claims data of a private health insurer in the United States, from 2009 to 2010 National Health and the Nutrition Examination Survey data, and from published meta-analyses. The model simulates the transitions among health states from initial physician visit to hypertension diagnosis, to treatment, to hypertension-related cardiovascular diseases, and patient death or resignation from the plan. We use the model to estimate cost-benefit ratios and both short- and long-run return on investment for home BP monitoring compared with clinic BP monitoring. Our results suggest that reimbursement of home BP monitoring is cost beneficial from an insurer's perspective for diagnosing and treating hypertension. Depending on the insurance plan and age group categories considered, estimated net savings associated with the use of home BP monitoring range from $33 to $166 per member in the first year and from $415 to $1364 in the long run (10 years). Return on investment ranges from $0.85 to $3.75 per dollar invested in the first year and from $7.50 to $19.34 per dollar invested in the long run.

  3. Summary of Activities for Health Monitoring of Composite Overwrapped Pressure Vessels Updated January 2014

    Science.gov (United States)

    Skow, Miles G.

    2014-01-01

    This three year project (FY12-14) will design and demonstrate the ability of new Magnetic Stress Gages for the measurement of stresses on the inner diameter of a Composite Overwrapped Pressure Vessel overwrap.

  4. Ambulatory blood pressure monitoring for the early identification of hypertension in pregnancy.

    Science.gov (United States)

    Ayala, Diana E; Hermida, Ramón C

    2013-03-01

    Gestational hypertension and preeclampsia are major contributors to perinatal morbidity and mortality. The diagnosis of gestational hypertension still relies on conventional clinic blood pressure (BP) measurements and thresholds of ≥140/90 mm Hg for systolic (SBP)/diastolic (DBP) BP. However, the correlation between BP level and target organ damage, cardiovascular disease risk, and long-term prognosis is greater for ambulatory BP monitoring (ABPM) than clinic BP measurement. Accordingly, ABPM has been suggested as the logical approach to overcoming the low sensitivity and specificity of clinic BP measurements in pregnancy. With the use of ABPM, differing predictable BP patterns throughout gestation have been identified for clinically healthy and hypertensive pregnant women. In normotensive pregnancies, BP steadily decreases up to the middle of gestation and then increases up to the day of delivery. In contrast, women who develop gestational hypertension or preeclampsia show stable BP during the first half of pregnancy and a continuous linear BP increase thereafter until delivery. Epidemiologic studies have also consistently reported sex differences in the 24-h patterns of ambulatory BP and heart rate. Typically, men exhibit a lower heart rate and higher BP than women, the differences being larger for SBP than DBP. Additionally, as early as in the first trimester of gestation, statistically significant increased 24-h SBP and DBP means characterize women complicated with gestational hypertension or preeclampsia compared with women with uncomplicated pregnancies. However, the normally lower BP in nongravid women as compared with men, additional decrease in BP during the second trimester of gestation in normotensive but not in hypertensive pregnant women, and significant differences in the 24-h BP pattern between healthy and complicated pregnancies at all gestational ages have not been taken into consideration when establishing reference BP thresholds for the

  5. Comparison of the cerebrospinal fluid (CSF) toluidine red unheated serum test and the CSF rapid plasma reagin test with the CSF venereal disease research laboratory test for diagnosis of neurosyphilis among HIV-negative syphilis patients in China.

    Science.gov (United States)

    Zhu, Lin; Gu, Xin; Peng, Rui-Rui; Wang, Cuini; Gao, Zixiao; Zhou, Pingyu; Gao, Ying; Shi, Mei; Guan, Zhifang; Seña, Arlene C

    2014-03-01

    In this study, we aimed to investigate the performance of nontreponemal antibody tests in cerebrospinal fluid (CSF) specimens from syphilis patients. From September 2009 to September 2012, CSF specimens were collected at the Shanghai Skin Disease Hospital in Shanghai, China, from 1,132 syphilis patients without HIV infection, including 154 with symptomatic and 56 with asymptomatic neurosyphilis. All of the CSF specimens underwent testing with a rapid plasma reagin (RPR) test, an RPR-V (commercial RPR antigen diluted 1:2 in 10% saline) test, the toluidine red unheated serum test (TRUST), and the Venereal Disease Research Laboratory (VDRL) test. Specificities, sensitivities, positive predictive values (PPVs), negative predictive values (NPVs), and kappa values were calculated to determine the performances of the tests. We compared results of the CSF-VDRL, CSF-RPR, CSF-RPR-V, and CSF-TRUST among patients with symptomatic and asymptomatic neurosyphilis who had reactive CSF-Treponema pallidum particle agglutination (TPPA) test results. Overall, the CSF-VDRL test was reactive in 261 patients (23.1%). There were no cases in which the CSF-VDRL was nonreactive and CSF-RPR, CSF-RPR-V, or CSF-TRUST was reactive. Agreement between the results of CSF-TRUST and CSF-RPR was almost perfect (κ=0.861), with substantial agreement between the results of CSF-RPR and CSF-RPR-V (κ=0.740). The sensitivities of CSF-VDRL, CSF-RPR, CSF-RPR-V, and CSF-TRUST were 81.4%, 76.2%, 79.5%, and 76.2%, respectively. Compared to CSF-VDRL, CSF-RPR, CSF-RPR-V, and CSF-TRUST had comparable PPVs and NPVs. However, the specificity of CSF-VDRL (90.3%) was significantly lower than those of the other tests (92.7 to 93.4%). Therefore, CSF-RPR, CSF-RPR-V, and CSF-TRUST can be considered alternative tests for neurosyphilis diagnosis in HIV-negative populations, particularly when the CSF-VDRL is not available.

  6. Wireless, Ultra-Low-Power Implantable Sensor for Chronic Bladder Pressure Monitoring.

    Science.gov (United States)

    Majerus, Steve J A; Garverick, Steven L; Suster, Michael A; Fletter, Paul C; Damaser, Margot S

    2012-06-01

    The wireless implantable/intracavity micromanometer (WIMM) system was designed to fulfill the unmet need for a chronic bladder pressure sensing device in urological fields such as urodynamics for diagnosis and neuromodulation for bladder control. Neuromodulation in particular would benefit from a wireless bladder pressure sensor which could provide real-time pressure feedback to an implanted stimulator, resulting in greater bladder capacity while using less power. The WIMM uses custom integrated circuitry, a MEMS transducer, and a wireless antenna to transmit pressure telemetry at a rate of 10 Hz. Aggressive power management techniques yield an average current draw of 9 μA from a 3.6-Volt micro-battery, which minimizes the implant size. Automatic pressure offset cancellation circuits maximize the sensing dynamic range to account for drifting pressure offset due to environmental factors, and a custom telemetry protocol allows transmission with minimum overhead. Wireless operation of the WIMM has demonstrated that the external receiver can receive the telemetry packets, and the low power consumption allows for at least 24 hours of operation with a 4-hour wireless recharge session.

  7. Development of a wireless intra-ocular pressure monitoring system for incorporation into a therapeutic glaucoma drainage implant

    Science.gov (United States)

    Kakaday, Tarun; Plunkett, Malcolm; McInnes, Steven; Li, Jim S. Jimmy; Voelcker, Nicolas H.; Craig, Jamie E.

    2008-12-01

    Glaucoma is a common cause of blindness. Wireless, continuous monitoring of intraocular pressure (IOP) is an important, unsolved goal in managing glaucoma. An IOP monitoring system incorporated into a glaucoma drainage implant (GDI) overcomes the design complexity associated with incorporating a similar system in a more confined space within the eye. The device consists of a micro-electro-mechanical systems (MEMS) based capacitive pressure sensor integrated with an inductor printed directly onto a polyimide printed circuit board (PCB). The device is designed to be incorporated onto the external plate of a therapeutic GDI. The resonance frequency changes as a function of IOP, and is tracked remotely using a spectrum analyzer. A theoretical model for the reader antenna was developed to enable maximal inductive coupling with the IOP sensor implant. Pressure chamber tests indicate that the sensor implant has adequate sensitivity in the IOP range with excellent reproducibility over time. Additionally, we show that sensor sensitivity does not change significantly after encapsulation with polydimethylsiloxane (PDMS) to protect the device from fluid environment. In vitro experiments showed that the signal measured wirelessly through sheep corneal and scleral tissue was adequate indicating potential for using the system in human subjects.

  8. Home Blood Pressure Monitoring as an Alternative to Confirm Diagnoses of Hypertension in Adolescents with Elevated Office Blood Pressure from a Brazilian State Capital.

    Science.gov (United States)

    Póvoa, Thaís Inacio Rolim; Jardim, Thiago Veiga; Carneiro, Carolina de Souza; Ferreira, Vanessa Roriz; Mendonça, Karla Lorena; Morais, Polyana Resende Silva de; Nascente, Flávia Miquetichuc Nogueira; Souza, Weimar Kunz Sebba Barroso de; Sousa, Ana Luiza Lima; Jardim, Paulo César Brandão Veiga

    2017-08-07

    Regional differences of using home blood pressure monitoring (HBPM) as an alternative to ambulatory blood pressure monitoring (ABPM) in hypertensive adolescents are unknown. Define if HBPM is an option to confirm diagnoses of hypertension in adolescents from a Brazilian capital with elevated office blood pressure (BP). Adolescents (12-18years) from public and private schools with BP > 90th percentile were studied to compare and evaluate the agreement among office BP measurements, HBPM and ambulatory BP monitoring. Office BP measurements, HBPM and ABPM were performed according to guidelines recommendations. Semi-automatic devices were used for BP measurements. Values of p 90 foram estudados para comparar e avaliar a concordância entre as medidas de PA, MRPA e MAPA. As medidas de PA de consultório, MRPA e MAPA foram realizadas de acordo com as recomendações das diretrizes. Foram utilizados dispositivos semiautomáticos para medições de PA. Valores de p valores médios da pressão arterial sistólica e pressão arterial diastólica da MRPA foram semelhantes aos valores de MAPA diurnos (120,3 ± 12,6 mmHg x 121,5 ± 9,8 mmHg - p = 0,111 e 69,4 ± 7,7 mmHg x 70,2 ± 6,6 mmHg - p = 0,139) e inferiores aos valores de consultório (127,3 ± 13,8 mmHg por 74,4 ± 9,5 mmHg - p < 0,001). Os gráficos de Bland-Altman mostraram boa concordância entre MRPA e MAPA. MRPA é uma opção para confirmar diagnóstico de hipertensão arterial em adolescentes de uma capital brasileira com PA de consultório elevada e pode ser usada como alternativa à MAPA.

  9. Role of Quantitative CSF Microscopy to Predict Culture Status and Outcome in HIV-Associated Cryptococcal Meningitis in a Brazilian Cohort

    Science.gov (United States)

    Vidal, José E.; Gerhardt, Juliana; Peixoto de Miranda, Érique J.; Dauar, Rafi F.; Oliveira Filho, Gilberto S.; Penalva de Oliveira, Augusto C.; Boulware, David R.

    2012-01-01

    Objectives To evaluate clinical, laboratory, and quantitative cerebrospinal fluid (CSF) cryptococcal cell counts for associations with in-hospital outcomes of HIV-infected patients with cryptococcal meningitis. Design Retrospective study. Methods 98 HIV-infected adult patients with CSF culture-proven cryptococcal meningitis admitted between January 2006 and June 2008 at a referral center in Sao Paulo, Brazil. Results Cryptococcal meningitis was the first AIDS-defining illness in 69% of whom 97% (95/98) had known prior HIV-infection. The median CD4+ T cell count was 39 cells/mcL (IQR: 17–87 cells/mcL). Prior antiretroviral therapy (ART) was reported in 50%. Failure to sterilize the CSF by 7–14 days was associated with baseline fungal burden of ≥10 yeasts/mcL by quantitative CSF microscopy (OR=15.3, 95% CI: 4.1–56.7;P14 days, altered mental status (P50,000 copies/mL (P=.036), ≥10 yeasts/mcL CSF at 7–14 days (P=.038), and intracranial pressure >50 cmH20 at 7–14 days (P=.007). Conclusion Most patients were aware of their HIV-status. Fungal burden of ≥10 yeasts/mcL by quantitative CSF microscopy predicted current CSF culture status and may be useful to customize the induction therapy. High uncontrolled intracranial pressure was associated with mortality. PMID:22578940

  10. Neurofilament Light Chain in Blood and CSF as Marker of Disease Progression in Mouse Models and in Neurodegenerative Diseases.

    Science.gov (United States)

    Bacioglu, Mehtap; Maia, Luis F; Preische, Oliver; Schelle, Juliane; Apel, Anja; Kaeser, Stephan A; Schweighauser, Manuel; Eninger, Timo; Lambert, Marius; Pilotto, Andrea; Shimshek, Derya R; Neumann, Ulf; Kahle, Philipp J; Staufenbiel, Matthias; Neumann, Manuela; Maetzler, Walter; Kuhle, Jens; Jucker, Mathias

    2016-07-01

    A majority of current disease-modifying therapeutic approaches for age-related neurodegenerative diseases target their characteristic proteopathic lesions (α-synuclein, Tau, Aβ). To monitor such treatments, fluid biomarkers reflecting the underlying disease process are crucial. We found robust increases of neurofilament light chain (NfL) in CSF and blood in murine models of α-synucleinopathies, tauopathy, and β-amyloidosis. Blood and CSF NfL levels were strongly correlated, and NfL increases coincided with the onset and progression of the corresponding proteopathic lesions in brain. Experimental induction of α-synuclein lesions increased CSF and blood NfL levels, while blocking Aβ lesions attenuated the NfL increase. Consistently, we also found NfL increases in CSF and blood of human α-synucleinopathies, tauopathies, and Alzheimer's disease. Our results suggest that CSF and particularly blood NfL can serve as a reliable and easily accessible biomarker to monitor disease progression and treatment response in mouse models and potentially in human proteopathic neurodegenerative diseases.

  11. Development of a telecare system based on ZigBee mesh network for monitoring blood pressure of patients with hemodialysis in health care centers.

    Science.gov (United States)

    Du, Yi-Chun; Lee, You-Yun; Lu, Yun-Yuan; Lin, Chia-Hung; Wu, Ming-Jei; Chen, Chung-Lin; Chen, Tainsong

    2011-10-01

    In Taiwan, the number of the patients needing dialysis increases rapidly in recent years. Because there is risk in every hemodialysis session, monitoring physiological status, such as blood pressure measurement every 30 min to 1 h is needed during about 4 h hemodialysis process. Therefore, an assisted measurement on blood pressure is needful in dialysis care centers. Telecare system (TCS) is regarded as one of important technique in the medical care. In this study, we utilized ZigBee wireless technique to establish a mesh network for monitoring blood pressure automatically and data storage in medical record system for display and further analysis. Moreover, while the blood pressure exceeds the normal range, the system could send a warning signal to remind, or inform the relatives and clinicians in health care center through the personal handy-phone system (PHS) immediately. The proposed system provides an assisted device for monitoring patients' blood pressure during hemodialysis process and saving medical manpower.

  12. Ambulatory blood pressure monitoring after 1 year on valsartan or amlodipine-based treatment: a VALUE substudy

    DEFF Research Database (Denmark)

    Pedersen, Ole Lederballe; Mancia, Giuseppe; Pickering, Thomas

    2007-01-01

    OBJECTIVE: The ambulatory blood pressure (ABP) monitoring substudy of the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial was carried out in a subset of patients from USA, Italy and Denmark. ABP was measured after 1 year in the trial, with the aim of evaluating comparability...... of ABP levels on valsartan (VAL) and amlodipine (AML)-based regimens. METHODS: ABP was measured every 20 min during a 25-h period after morning administration of medicine; 659 patients were available for intention-to-treat analysis. RESULTS: Office blood pressure (BP) differences were smaller than...... of combined cardiovascular endpoints--superior to the relationship to office BP. CONCLUSIONS: In these elderly high-risk patients, diastolic ABP levels tended to be less predictive than systolic, and daytime less predictive than night-time for all cardiovascular endpoints. The findings underline...

  13. Health Monitoring of Composite Overwrapped Pressure Vessels (COPVs) Using Meandering Winding Magnetometer ((MWM(Registered Trademark)) Eddy Current Sensors

    Science.gov (United States)

    Russell, Rick; Grundy, David; Jablonski, David; Martin, Christopher; Washabaugh, Andrew; Goldfine, Neil

    2011-01-01

    There are 3 mechanisms that affect the life of a COPV are: a) The age life of the overwrap; b) Cyclic fatigue of the metallic liner; c) Stress Rupture life. The first two mechanisms are understood through test and analysis. A COPV Stress Rupture is a sudden and catastrophic failure of the overwrap while holding at a stress level below the ultimate strength for an extended time. Currently there is no simple, deterministic method of determining the stress rupture life of a COPV, nor a screening technique to determine if a particular COPV is close to the time of a stress rupture failure. Conclusions: Demonstrated a correlation between MWM response and pressure or strain. Demonstrated the ability to monitor stress in COPV at different orientations and depths. FA41 provides best correlation with bottle pressure or stress.

  14. Electronic system for monitoring the frequency and pressure of mastication: study and approach for its design.

    Science.gov (United States)

    Nakamura, Orlando K; Garcia, Daniel O; Villavicencio, Emilio A; Navarro, Luis A; Torres, Miguel A; Huamani, Robinson; Yabar, Leopoldo F

    2010-01-01

    The objective of this work is to study and design a portable non invasive prototype which allows us to supervise the mastication frequency and pressure for specific meals, performing an analysis of sounds and pressures generated by facial muscles when they are chewing. These variables have a direct influence on people nutritious and dietary habits; also, a quickly eating makes people ingest a lot of food instead he needs generating overweight on him. On the other hand, there is no so much study for upheaval of temporal-mandible joints (TMJ) in Peru, keeping as reference that unilateral mastication is one of the principal causes on myofacial pains but, as obesity, there are no studies in Peru about how to prevent these pathologies. In consequence, we propose the development of this prototype which, additional to supervise variables such as mastication frequency and pressure, will allow to the patient an self-correction of his habits.

  15. [Quantification of gait using insole type foot pressure monitor : clinical application for chronic hemiplegia].

    Science.gov (United States)

    Naito, Yutaro; Kimura, Yoshiko; Hashimoto, Takashi; Mori, Masao; Takemoto, Yoshimi

    2014-03-01

    Home-based stroke hemiplegia patients tend to fall easily. Poor toe clearance is reported to be one of the causes of falling, although there are many other related factors. We developed a low-priced insole type portable foot pressure measurement device, and measured the foot pressure distribution and the foot pressure-time curve of 20 chronic hemiplegia patients and compared them with 36 healthy controls. We also analyzed the outdoor gait of a chronic hemiplegia patient on flat ground, on rough terrain, walking up stairs and on a downward slope. The result was that the load rate of the unaffected heel was significantly increased in hemiplegic gait, and there was a significant negative correlation between the affected side stance phase rate and gait time for 10 m distance (r = -0.73, P hemiplegia patients tend to be highly dependent on their unaffected side during indoor and outdoor gait.

  16. Fiber optic sensor for hydrostatic pressure and temperature measurement in riverbanks monitoring

    Science.gov (United States)

    Schenato, Luca; Aneesh, Rajendran; Palmieri, Luca; Galtarossa, Andrea; Pasuto, Alessandro

    2016-08-01

    An optical fiber sensor for the simultaneous measurement of hydrostatic pressure and temperature in soil embankments is presented. It exploits the differential strain induced on a fiber in a dual-chamber case, constituting the sensor body. The strain, either induced by the pressure or by the temperature, is optically measured by means of coherent frequency domain reflectometry and variations induced by the two physical phenomena are discriminated because of the different behavior of the two chambers. Characterization of the sensor is presented and discussed. The prototype shows promising performance: temperature and pressure sensitivities are approximately -7 GHz/°C and -3.2 GHz/kPa, respectively, with accuracies of 0.5 °C and 0.3 kPa.

  17. Effects of education on self-monitoring of blood pressure based on BASNEF model in hypertensive patients

    Directory of Open Access Journals (Sweden)

    Mohammad Hossein Baghianimoghadam

    2010-01-01

    Full Text Available Background: Hypertension is one of the most important health problems. Self-monitoring may be an effective method for controlling this disease. The aim of this study is to determine the effectiveness of education on blood pressure self-monitoring in patients with hypertension based on BASNEF model. Methods: In this clinical trial, 150 outpatients with hypertension were randomly selected from those referred to private clinics in Yazd, Iran, during 2008. They were divided in two groups. The data were collected by a validated and reliable questionnaire. The implementing educational program was continued for 2 months and the pre-test and post-test had an interval of 2-months. BASNEF model was applied to explain the motivation of a behavior. Descriptive analysis, correlation test and also regression analysis were used to analyze data. Results: The respondents acquired 17.72% of total score for self-monitoring behavior, 47.03% of attitude, 12.37% of subjective norms, 33.46% of intention and 50.95% of enabling factors. After intervention, there were significant increases in self-monitoring behavior (173.31%, attitude (62.60%, subjective norms (54.70%, intention (129.93% and enabling factors (46.62% in the intervention group. There was no significant difference between the constructs of BASNEF model in the control group after intervention compared to the baseline values (p > 0.05. Conclusions: The results of this study showed that the level of self-monitoring behavior in the patients was low. Educational programs are helpful and necessary to improve self-monitoring behavior in patients with hypertension.

  18. Self-monitoring blood pressure in patients with hypertension: an internet-based survey of UK GPs.

    Science.gov (United States)

    Fletcher, Benjamin R; Hinton, Lisa; Bray, Emma P; Hayen, Andrew; Hobbs, Fd Richard; Mant, Jonathan; Potter, John F; McManus, Richard J

    2016-11-01

    Previous research suggests that most GPs in the UK use self-monitoring of blood pressure (SMBP) to monitor the control of hypertension rather than for diagnosis. This study sought to assess current practice in the use of self-monitoring and any changes in practice following more recent guideline recommendations. To survey the views and practice of UK GPs in 2015 with regard to SMBP and compare them with a previous survey carried out in 2011. Web-based survey of a regionally representative sample of 300 UK GPs. GPs completed an online questionnaire concerning the use of SMBP in the management of hypertension. Analyses comprised descriptive statistics, tests for between-group differences (z, Wilcoxon signed-rank, and χ(2) tests), and multivariate logistic regression. Results were available for 300 GPs (94% of those who started the survey). GPs reported using self-monitoring to diagnose hypertension (169/291; 58%; 95% confidence interval (CI) = 52 to 64) and to monitor control (245/291; 84%; 95% CI = 80 to 88), the former having significantly increased since 2011 (from 37%; 95% CI = 33 to 41; PGPs used higher systolic thresholds for diagnosis (118/169; 70%; 95% CI = 63 to 77) and treatment (168/225; 75%; 95% CI = 69 to 80) than recommended in guidelines, and under half (120/289; 42%; 95% CI = 36 to 47) adjusted the SMBP results to guide treatment decisions. Since new UK national guidance in 2011, GPs are more likely to use SMBP to diagnose hypertension. However, significant proportions of GPs continue to use non-standard diagnostic and monitoring thresholds. The use of out-of-office methods to improve the accuracy of diagnosis is unlikely to be beneficial if suboptimal thresholds are used. © British Journal of General Practice 2016.

  19. Pressure ulcer and wounds reporting in NHS hospitals in England part 2: Survey of monitoring systems.

    Science.gov (United States)

    Coleman, Susanne; Smith, Isabelle L; Nixon, Jane; Wilson, Lyn; Brown, Sarah

    2016-02-01

    This is the second of a two related papers describing work undertaken to compare and contrast Pressure Ulcer (PU) monitoring systems across NHS in-patient facilities in England. The work comprised 1) a PU/Wound Audit (PUWA) and 2) a survey of PU monitoring systems. This second paper focusses on the survey which explores differences in the implementation of PU adverse event monitoring systems in 24 NHS hospital Trusts in England. The survey questionnaire comprised 41 items incorporating single and multiple response options and free-text items and was completed by the PUWA Trust lead in liaison with key people in the organisation. All 24 (100%) Trusts returned the questionnaire, with high levels of data completeness (99.1%). The questionnaire results showed variation between Trusts in relation to the recording of PUs and their reporting as part of NHS prevalence and incident monitoring systems and to Trust boards and healthcare commissioners including the inclusion (or not) of device ulcers, unstageable ulcers, Deep Tissue Injury, combined PUs/Incontinence Associated Dermatitis, category ≥ 1 ulcers or category ≥ 2 ulcers, inherited ulcers, acquired ulcers, avoidable and unavoidable ulcers and the definition of Present On Admission. These fundamental differences in reporting preclude Trust to Trust comparisons of PU prevalence and incident reporting and monitoring systems due to variation in local application and data collection methods. The results of this work and the PUWA led to the development of recommendations for PU monitoring practice, many of which are internationally relevant.

  20. Casual and ambulatory blood pressure monitoring in children with renal scarring

    Directory of Open Access Journals (Sweden)

    Miloševski Gordana

    2005-01-01

    Full Text Available INTRODUCTION Renal scarring is the most common cause of arterial hypertension in children. High blood pressure (BP and microalbuminuria contribute to the progression of chronic renal disease. OBJECTIVE The aims of the study were: to assess BP in children with renal scarring by continuous ambulatory blood pressure measurement (ABPM in comparison to the casual method (CBP, and to determine the correlation between ambulatory blood pressure (ABP and/or casual blood pressure (CBP values and proteinuria in children with renal scarring. METHOD This forward-looking study comprised thirty-five children (26 girls and 9 boys, aged between 3-13 years, 10.4±3.9, X+SD. Blood pressure was measured using the casual method (CBP with a mercury manometer; BP was measured three times and the average was taken as a referent value. ABPM was performed using the oscillometric method with the Space Labs device, model 90207. RESULTS 45.71% of patients were classified as hypertensive by ABPM, while only 22.6% of CBP measurements were above the 95th percentile (p<0.01. "White coat hypertension" was present in 40% of the patients. Non-dipping BP alteration was detected in 37.14% of the patients. CONCLUSION Nocturnal systolic hypertension (systolic non-dipping alteration is very frequent in children with renal scarring. Nocturnal diastolic blood pressure, detectable only via ABPM, is positively correlated with proteinuria and may be an initial sign of the progression of renal scarring. ABPM is more sensitive than CBP in the evaluation of BP in children with renal scarring.

  1. Real-Time Optical Monitoring of Flow Kinetics and Gas Phase Reactions Under High-Pressure OMCVD Conditions

    Science.gov (United States)

    Dietz, N.; McCall, S.; Bachmann, K. J.

    2001-01-01

    This contribution addresses the real-time optical characterization of gas flow and gas phase reactions as they play a crucial role for chemical vapor phase depositions utilizing elevated and high pressure chemical vapor deposition (HPCVD) conditions. The objectives of these experiments are to validate on the basis of results on real-time optical diagnostics process models simulation codes, and provide input parameter sets needed for analysis and control of chemical vapor deposition at elevated pressures. Access to microgravity is required to retain high pressure conditions of laminar flow, which is essential for successful acquisition and interpretation of the optical data. In this contribution, we describe the design and construction of the HPCVD system, which include access ports for various optical methods of real-time process monitoring and to analyze the initial stages of heteroepitaxy and steady-state growth in the different pressure ranges. To analyze the onset of turbulence, provisions are made for implementation of experimental methods for in-situ characterization of the nature of flow. This knowledge will be the basis for the design definition of experiments under microgravity, where gas flow conditions, gas phase and surface chemistry, might be analyzed by remote controlled real-time diagnostics tools, developed in this research project.

  2. SOI built-in heat spreader with temperature and pressure integrated sensors for cooling optimization and in situ monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Bercu, Bogdan, E-mail: bogdan_bercu@yahoo.com [Institute of Microelectronics, Electromagnetism and Photonics (IMEP-LAHC) 3, parvis Louis Neel - BP 257, 38016 Grenoble Cedex 01 (France); Montes, Laurent; Morfouli, Panagiota [Institute of Microelectronics, Electromagnetism and Photonics (IMEP-LAHC) 3, parvis Louis Neel - BP 257, 38016 Grenoble Cedex 01 (France)

    2011-03-15

    This contribution presents an original solution for sensor integration into a heat spreader which is directly micromachined into the silicon substrate of the device to be cooled. Having both a high thermal conductivity coefficient and a high level of miniaturization, the vapor chamber heat spreader provides a high robustness due to the absence of any moving pumping parts. Simulation results as well as experimental results obtained with a prototype of the heat spreader with integrated temperature and pressure microsensors are presented. The results concerning device cooling optimization using the integrated sensors are highlighting the interest of this approach for accurate in situ monitoring and cooling optimization of silicon-integrated heat spreaders.

  3. Evidence of a plate-wide tectonic pressure pulse provided by extensometric monitoring in the Balkan Mountains (Bulgaria

    Directory of Open Access Journals (Sweden)

    Briestenský Miloš

    2015-10-01

    Full Text Available The EU-TecNet monitoring network uses customized three-dimensional extensometers to record transient deformations across individual faults. This paper presents the first results from two newly established monitoring points in the Balkan Mountains in Bulgaria. The data from Saeva Dupka, recorded across an EEN-WWS striking fault, show sinistral strike-slip along the fault and subsidence of the southern block. Much of the subsidence occurred around the time of the distal MW = 5.6 Pernik Earthquake. An important transient deformation event, which began in autumn 2012, was reflected by significant compression and following extension, across the monitored fault. The data from Bacho Kiro, recorded across a NE–SW striking fault, show sinistral strike-slip along the fault and subsidence of the north-western block. The same important deformation event was reflected by changes in the strike-slip, dip-slip, and horizontal opening/closing trends. These results have been compared to data from other monitoring points in the Western Carpathians, External Dinarides, and Tian Shan. Many of the sites show evidence of simultaneous displacement anomalies and this observation is interpreted as a reflection of the plate-wide propagation of a tectonic pressure pulse towards the end of 2012.

  4. Circuit for detecting initial systole and dicrotic notch. [for monitoring arterial pressure

    Science.gov (United States)

    Gebben, V. D.; Webb, J. A., Jr. (Inventor)

    1974-01-01

    Circuitry is disclosed for processing an arterial pressure waveform to produce during any one cycle a pulse corresponding to the initial systole and a pulse corresponding to the dicrotic notch. In a first channel, an electrical analog of the arterial pressure waveform is filtered and then compared to the original waveform to produce an initial systole signal. In a second channel, the analog is differentiated, filtered, and fed through a gate controlled by pulses from the first channel to produce an electrical pulse corresponding to the dicrotic notch.

  5. CSF neurofilament concentration reflects disease severity in frontotemporal degeneration

    Science.gov (United States)

    Scherling, Carole S.; Hall, Tracey; Berisha, Flora; Klepac, Kristen; Karydas, Anna; Coppola, Giovanni; Kramer, Joel H.; Rabinovici, Gil; Ahlijanian, Michael; Miller, Bruce L.; Seeley, William; Grinberg, Lea T.; Rosen, Howard; Meredith, Jere; Boxer, Adam L.

    2014-01-01

    Objective Cerebrospinal fluid (CSF) neurofilament light chain (NfL) concentration is elevated in neurological disorders including frontotemporal degeneration (FTD). We investigated the clinical correlates of elevated CSF NfL levels in FTD. Methods CSF NfL, amyloid-β42 (Aβ42), tau and phosphorylated tau (ptau) concentrations were compared in 47 normal controls (NC), 8 asymptomatic gene carriers (NC2) of FTD-causing mutations, 79 FTD (45 behavioral variant frontotemporal dementia [bvFTD], 18 progressive nonfluent aphasia [PNFA], 16 semantic dementia [SD]), 22 progressive supranuclear palsy, 50 Alzheimer’s disease, 6 Parkinson’s disease and 17 corticobasal syndrome patients. Correlations between CSF analyte levels were performed with neuropsychological measures and the Clinical Dementia Rating scale sum of boxes (CDRsb). Voxel-based morphometry of structural MR images determined the relationship between brain volume and CSF NfL. Results Mean CSF NfL concentrations were higher in bvFTD, SD and PNFA than other groups. NfL in NC2 was similar to NC. CSF NfL, but not other CSF measures, correlated with CDRsb and neuropsychological measures in FTD, and not in other diagnostic groups. Analyses in two independent FTD cohorts and a group of autopsy verified or biomarker enriched cases confirmed the larger group analysis. In FTD, gray and white matter volume negatively correlated with CSF NfL concentration, such that individuals with highest NfL levels exhibited the most atrophy. Interpretation CSF NfL is elevated in symptomatic FTD and correlates with disease severity. This measurement may be a useful surrogate endpoint of disease severity in FTD clinical trials. Longitudinal studies of CSF NfL in FTD are warranted. PMID:24242746

  6. Association between central obesity and circadian parameters of blood pressure from the korean ambulatory blood pressure monitoring registry: Kor-ABP registry.

    Science.gov (United States)

    Kang, In Sook; Pyun, Wook Bum; Shin, Jinho; Kim, Ju Han; Kim, Soon Gil; Shin, Gil Ja

    2013-10-01

    Central obesity has been reported as a risk for atherosclerosis and metabolic syndrome. The influence of central obesity on diurnal blood pressure (BP) has not been established. In this study, we investigated the influence of central obesity on the circadian parameters of BP by 24 hr ambulatory BP monitoring. Total 1,290 subjects were enrolled from the Korean Ambulatory BP registry. Central obesity was defined as having a waist circumference≥90 cm in males and ≥85 cm in females. The central-obese group had higher daytime systolic BP (SBP), nighttime SBP and diastolic BP (DBP) than the non-obese group (all, P<0.001). There were no differences in nocturnal dipping (ND) patterns between the groups. Female participants showed a higher BP mean difference (MD) than male participants with concerns of central obesity (daytime SBP MD 5.28 vs 4.27, nighttime SBP MD 6.48 vs 2.72) and wider pulse pressure (PP). Central obesity within the elderly (≥65 yr) also showed a higher BP MD than within the younger group (daytime SBP MD 8.23 vs 3.87, daytime DBP 4.10 vs 1.59). In conclusion, central obesity has no influence on nocturnal dipping patterns. However, higher SBP and wider PP are associated with central obesity, which is accentuated in women.

  7. Moderator's view: Ambulatory blood pressure monitoring and home blood pressure for the prognosis, diagnosis and treatment of hypertension in dialysis patients.

    Science.gov (United States)

    Zoccali, Carmine; Tripepi, Rocco; Torino, Claudia; Tripepi, Giovanni; Mallamaci, Francesca

    2015-09-01

    Major health agencies now recommend the systematic application of ambulatory blood pressure monitoring (ABPM) for the diagnosis of hypertension. Given the exceedingly high prevalence of nocturnal hypertension, masked and white coat hypertension and the overt inadequacy of peridialysis (pre-, intra- and post-dialysis) BP measurements, more extensive application of ABPM for the diagnosis of hypertension in dialysis patients would appear logical. In a recent survey performed in NDT Educational, organizational problems and/or cognitive resistance emerged as important factors hindering more extensive application of ABPM and home BP by nephrologists. External validation of observations made in landmark studies in a single institution about hypertension subcategorization by ABPM is urgently needed. Furthermore, apparent cognitive resistance by nephrologists may be justified by the fact that these techniques have been insufficiently tested in the dialysis population for applicability in everyday clinical practice, tolerability, organizational impact and cost-effectiveness. We should be more resolute in abandoning peridialysis measurements for diagnosing and treating hypertension in haemodialysis patients. Home BP is a formidable educational instrument for patient empowerment and self-care, and evidence exists that this technique is superior to peridialysis values to better hypertension control as defined on the basis of ABPM. We should strive to promote more extensive application of home BP monitoring to diagnose and manage hypertension in haemodialysis patients. ABPM with novel, user friendly and better tolerated techniques is to be awaited in the near future.

  8. Radial artery applanation tonometry for continuous non-invasive arterial pressure monitoring in intensive care unit patients: comparison with invasively assessed radial arterial pressure.

    Science.gov (United States)

    Meidert, A S; Huber, W; Müller, J N; Schöfthaler, M; Hapfelmeier, A; Langwieser, N; Wagner, J Y; Eyer, F; Schmid, R M; Saugel, B

    2014-03-01

    Radial artery applanation tonometry technology can be used for continuous non-invasive measurement of arterial pressure (AP). The purpose of this study was to evaluate this AP monitoring technology in intensive care unit (ICU) patients in comparison with invasive AP monitoring using a radial arterial catheter. In 24 ICU patients (German university hospital), AP values were simultaneously recorded on a beat-to-beat basis using radial artery applanation tonometry (T-Line system; Tensys Medical, San Diego, CA, USA) and a radial arterial catheter (contralateral arm). The primary endpoint of the study was to investigate the accuracy and precision of the non-invasively assessed AP measurements with the Bland-Altman method based on averaged 10 beat AP epochs (n=2993 10 beat epochs). For mean AP (MAP), systolic AP (SAP), and diastolic AP (DAP), we observed a bias (±standard deviation of the bias; 95% limits of agreement; percentage error) of +2 mm Hg (±6; -11 to +15 mm Hg; 15%), -3 mm Hg (±15; -33 to +27 mm Hg; 23%), and +5 mm Hg (±7; -9 to +19 mm Hg; 22%), respectively. In ICU patients, MAP and DAP measurements obtained using radial artery applanation tonometry show clinically acceptable agreement with invasive AP determination with a radial arterial catheter. While the radial artery applanation tonometry technology also allows SAP measurements with high accuracy, its precision for SAP measurements needs to be further improved.

  9. Understanding Challenges and Opportunities of Preventive Blood Pressure Self-Monitoring at Home

    DEFF Research Database (Denmark)

    Grönvall, Erik; Verdezoto, Nervo

    2013-01-01

    The herein presented study explores socio-technical complexities that may occur when introducing preventive health-measurement technologies in older adults’ daily routines and everyday lives. Using mainly blood pressure measurements in private homes, the study applied qualitative and quantitative...

  10. 49 CFR 571.138 - Standard No. 138; Tire pressure monitoring systems.

    Science.gov (United States)

    2010-10-01

    ... period corresponding to S7.1 filed pursuant to 49 CFR 585.66. The vehicles are counted in fulfillment of... those vehicles with dual wheels on an axle, according to the phase-in schedule specified in S7 of this....1General. To the extent provided in S7, each vehicle must be equipped with a tire pressure...

  11. Low-power wireless micromanometer system for acute and chronic bladder-pressure monitoring.

    Science.gov (United States)

    Majerus, Steve J A; Fletter, Paul C; Damaser, Margot S; Garverick, Steven L

    2011-03-01

    This letter describes the design, fabrication, and testing of a wireless bladder-pressure-sensing system for chronic, point-of-care applications, such as urodynamics or closed-loop neuromodulation. The system consists of a miniature implantable device and an external RF receiver and wireless battery charger. The implant is small enough to be cystoscopically implanted within the bladder wall, where it is securely held and shielded from the urine stream. The implant consists of a custom application-specific integrated circuit (ASIC), a pressure transducer, a rechargeable battery, and wireless telemetry and recharging antennas. The ASIC includes instrumentation, wireless transmission, and power-management circuitry, and on an average draws less than 9 μA from the 3.6-V battery. The battery charge can be wirelessly replenished with daily 6-h recharge periods that can occur during the periods of sleep. Acute in vivo evaluation of the pressure-sensing system in canine models has demonstrated that the system can accurately capture lumen pressure from a submucosal implant location.

  12. When Errors Count: An EEG Study on Numerical Error Monitoring under Performance Pressure

    Science.gov (United States)

    Schillinger, Frieder L.; De Smedt, Bert; Grabner, Roland H.

    2016-01-01

    In high-stake tests, students often display lower achievements than expected based on their skill level--a phenomenon known as choking under pressure. This imposes a serious problem for many students, especially for test-anxious individuals. Among school subjects, mathematics has been shown to be particularly vulnerable to choking. To succeed in a…

  13. Data quality assurance in pressure transducer-based automatic water level monitoring

    Science.gov (United States)

    Submersible pressure transducers integrated with data loggers have become relatively common water-level measuring devices used in flow or well water elevation measurements. However, drift, linearity, hysteresis and other problems can lead to erroneous data. Researchers at the USDA-ARS in Watkinsvill...

  14. In-situ monitoring during pulsed laser deposition using RHEED at high pressure

    NARCIS (Netherlands)

    Blank, David H.A.; Rijnders, Augustinus J.H.M.; Koster, Gertjan; Rogalla, Horst

    1998-01-01

    Reflection high energy electron diffraction (RHEED) is, due to its surface sensitivity, often used for the analysis and monitoring of thin film growth in ultra-high vacuum deposition systems. RHEED is usually applied in combination with pulsed laser deposition (PLD) by adjusting the background

  15. Dikes under Pressure - Monitoring the Vulnerability of Dikes by Means of SAR Interferometry

    Science.gov (United States)

    Marzahn, Philip; Seidel, Moritz; Ludwig, Ralf

    2016-04-01

    Dikes are the main man made structures in flood protection systems for the protection of humans and economic values. Usually dikes are built with a sandy core and clay or concrete layer covering the core. Thus, dikes are prone to a vertical shrinkage due to soil physical processes such as reduction of pore space and gravity increasing the risk of a crevasse during floods. In addition, this vulnerability is amplified by a sea level rise due to climate change. To guarantee the stability of dikes, a labourer intensive program is carried out by national authorities monitoring the dikes by visual inspection. In the presented study, a quantitative approach is presented using SAR Interferometry for the monitoring of the stability of dikes from space. In particular, the vertical movement of dikes due to shrinkage is monitored using persistent scatterer interferometry. Therefore three different types of dikes have been investigated: a sea coast dike with a concrete cover, a sea coast dike with short grass cover and a smaller river dike with grass cover. All dikes are located in Germany. Results show the potential of the monitoring technique as well as spatial differences in the stability of dikes with subsidence rates in parts of a dike up to 7 mm/a.

  16. Speaking one’s second language under time pressure : An ERP study on verbal self-monitoring in German-Dutch bilinguals

    NARCIS (Netherlands)

    Schiller, N.O.

    2009-01-01

    This study addresses how verbal self-monitoring and the Error-Related Negativity (ERN) are affected by time pressure when a task is performed in a second language as opposed to performance in the native language. German–Dutch bilinguals were required to perform a phoneme-monitoring task in Dutch

  17. Speaking one’s second language under time pressure : An ERP study on verbal self-monitoring in German-Dutch bilinguals

    NARCIS (Netherlands)

    Schiller, N.O.

    2009-01-01

    This study addresses how verbal self-monitoring and the Error-Related Negativity (ERN) are affected by time pressure when a task is performed in a second language as opposed to performance in the native language. German–Dutch bilinguals were required to perform a phoneme-monitoring task in Dutch wit

  18. Cerebrospinal fluid flow and production in patients with normal pressure hydrocephalus studied by MRI

    DEFF Research Database (Denmark)

    Gideon, P; Ståhlberg, F; Thomsen, C

    1994-01-01

    An interleaved velocity-sensitised fast low-angle shot pulse sequence was used to study cerebrospinal fluid (CSF) flow in the cerebral aqueduct, and supratentorial CSF production in 9 patients with normal pressure hydrocephalus (NPH) and 9 healthy volunteers. The peak aqueduct CSF flow, both caudal...

  19. Stem Cell Mobilization with G-CSF versus Cyclophosphamide plus G-CSF in Mexican Children

    Directory of Open Access Journals (Sweden)

    José Eugenio Vázquez Meraz

    2016-01-01

    Full Text Available Fifty-six aphaereses were performed in 23 pediatric patients with malignant hematological and solid tumors, following three different protocols for PBPC mobilization and distributed as follows: A: seventeen mobilized with 4 g/m2 of cyclophosphamide (CFA and 10 μg/kg/day of granulocyte colony stimulating factor (G-CSF, B: nineteen with CFA + G-CSF, and C: twenty only with G-CSF when the WBC count exceeded 10 × 109/L. The average number of MNC/kg body weight (BW/aphaeresis was 0.4 × 108 (0.1–1.4, 2.25 × 108 (0.56–6.28, and 1.02 × 108 (0.34–2.5 whereas the average number of CD34+ cells/kg BW/aphaeresis was 0.18 × 106/kg (0.09–0.34, 1.04 × 106 (0.19–9.3, and 0.59 × 106 (0.17–0.87 and the count of CFU/kg BW/aphaeresis was 1.11 × 105 (0.31–2.12, 1.16 × 105 (0.64–2.97, and 1.12 × 105 (0.3–6.63 in groups A, B, and C, respectively. The collection was better in group B versus group A (p=0.007 and p=0.05, resp. and in group C versus group A (p=0.08 and p=0.05, resp.. The collection of PBPCs was more effective in the group mobilized with CFM + G-CSF when the WBC exceeded 10 × 103/μL in terms of MNC and CD34+ cells and there was no toxicity of the chemotherapy.

  20. EXPRESSION OF RHGM-CSF GENE IN EUKARYOCYTE BY LIPOFECTION

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    objective: To recombinant the nearly natural humangranulocyte-macrophage-colony stimulating factor (GM-CSF) for supplying more safe and steady expressed cytokine in clinic. Method: The eukaryotic recombinant pcDNA3.1-GM-CSF plasmid which was controlled by the CMV promoter was transferred into CHO cell by lipofectamine, selected by G418 and the positive clones was got. The recombinant vector which was rejoined into the groups of DNA of CHO was identified by PCR. Results: The results showed that the protein of rhGM-CSF was about 28 KD by using ELISA, SDS-PAGE and Western blot. Conclusion: rhGM-CSF was expressed steadily and highly. The rhGM-CSF will be of more use value.

  1. In-situ spectroscopic monitoring of the ambient pressure hydrogenation of C2 to ethane on Pt(111)

    Science.gov (United States)

    Krooswyk, Joel D.; Kruppe, Christopher M.; Trenary, Michael

    2016-10-01

    The hydrogenation of C2 molecules formed on the Pt(111) surface through acetylene exposure at 750 K was monitored in-situ with reflection absorption infrared spectroscopy (RAIRS) in the presence of up to 10 Torr of H2. The coverage of post-reaction surface carbon was measured with Auger electron spectroscopy. The RAIR spectra show that C2 is hydrogenated to an ethylidyne intermediate. The hydrogenation of ethylidyne was also monitored at 400 K for H2(g) pressures of 1.0 × 10- 2 to 10 Torr. At H2(g) pressures greater than 1.0 Torr, ethylidyne is completely hydrogenated. In an attempt to probe the nature of the C2 adsorption sites, RAIR spectra of coadsorbed CO were obtained. It is found that while C2 does not block CO adsorption, the spectra indicate that the surface carbon is free of hydrogen. In contrast, ethylidyne blocks CO adsorption sites. In the presence of coadsorbed CO, complete hydrogenation of ethylidyne occurs at 450 K versus 400 K in the absence of CO.

  2. The pharmacist and the management of arterial hypertension: the role of blood pressure monitoring and telemonitoring.

    Science.gov (United States)

    Omboni, Stefano; Sala, Elisa

    2015-02-01

    Randomized controlled trials have documented that a team of health care professionals which includes a physician, a nurse and a community pharmacist may improve the benefit and adherence of anti-hypertensive therapy. If such a health care model relies on blood pressure telemonitoring, it can promote a stronger relationship between health care professionals and patients, and further improve BP control of hypertension. The major benefit of this collaborative approach is to center the patient's management in a tailored way, providing comprehensive and preventive care based on health information technologies. In this review, the authors summarize recent clinical studies that evaluate the role of the community pharmacist in BP measurements, and in hypertension screening and control. The authors also describe the advantages of using blood pressure telemonitoring in home and ambulatory settings to evaluate potential alternatives to primary care in hypertension management.

  3. Non-Invasive Ultrasonic Diagnosing and Monitoring of Intracranial Pressure/Volume

    Science.gov (United States)

    2001-10-01

    related to cardiovascular parameters. ICP VI, Eds. Miller JD, Teasdale GM, Rowan JO, Galbraith SL, Mendelow AD. Springer-Verlag Berlin Heidelberg, 290...Galbraith AD Mendelow (Springer Berlin Heidelberg) 305-309 43. Hayashi M, Handa Y, Kobayashi H, Kawano H, Ishii H, Hirose S (1991). Plateau-wave...Galbraith SL, Mendelow AD Springer-Verlag Berlin Heidelberg. 151-155 72. Maeda M, Tanaka K, Nishimur S, Matsuura S (1986). Pressure wave-like changes in

  4. Use of large-scale acoustic monitoring to assess anthropogenic pressures on Orthoptera communities.

    Science.gov (United States)

    Penone, Caterina; Le Viol, Isabelle; Pellissier, Vincent; Julien, Jean-François; Bas, Yves; Kerbiriou, Christian

    2013-10-01

    Biodiversity monitoring at large spatial and temporal scales is greatly needed in the context of global changes. Although insects are a species-rich group and are important for ecosystem functioning, they have been largely neglected in conservation studies and policies, mainly due to technical and methodological constraints. Sound detection, a nondestructive method, is easily applied within a citizen-science framework and could be an interesting solution for insect monitoring. However, it has not yet been tested at a large scale. We assessed the value of a citizen-science program in which Orthoptera species (Tettigoniidae) were monitored acoustically along roads. We used Bayesian model-averaging analyses to test whether we could detect widely known patterns of anthropogenic effects on insects, such as the negative effects of urbanization or intensive agriculture on Orthoptera populations and communities. We also examined site-abundance correlations between years and estimated the biases in species detection to evaluate and improve the protocol. Urbanization and intensive agricultural landscapes negatively affected Orthoptera species richness, diversity, and abundance. This finding is consistent with results of previous studies of Orthoptera, vertebrates, carabids, and butterflies. The average mass of communities decreased as urbanization increased. The dispersal ability of communities increased as the percentage of agricultural land and, to a lesser extent, urban area increased. Despite changes in abundances over time, we found significant correlations between yearly abundances. We identified biases linked to the protocol (e.g., car speed or temperature) that can be accounted for ease in analyses. We argue that acoustic monitoring of Orthoptera along roads offers several advantages for assessing Orthoptera biodiversity at large spatial and temporal extents, particularly in a citizen science framework. © 2013 Society for Conservation Biology.

  5. Clinical evaluation of the Philips 5306B electronic blood pressure monitor.

    Science.gov (United States)

    Hall, C L; Goodfellow, J; Waites, J

    1991-01-01

    A patient-recorded home blood pressure series using an electronic manometer is used increasingly to provide a representative sample of blood pressure (BP) and to avoid frequent office visits and office rises in BP. Few of the many available electronic manometers have undergone rigorous testing and validation against a standard mercury manometer. We have evaluated fully the commonly used Philips 5306B electronic manometer against a Hawksley random zero mercury manometer employing a randomized, single-blind, crossover design and statistical analyses that have been validated previously. Although correlation coefficients greater than 0.9 were achieved for both systolic and diastolic pressure, the electronic manometer gave systolic and diastolic readings that differed from the mercury manometer by greater than or equal to +/- 5 mmHg in some 33% of patients and by greater than or equal to +/- 1- mmHg in some 18% of patients. Thus, in common with most electronic manometers, the Philips 5306B needs to be improved to correlate more closely with the standard mercury manometer to enhance its clinical usefulness.

  6. Variability of CSF Alzheimer's disease biomarkers: implications for clinical practice.

    Directory of Open Access Journals (Sweden)

    Stephanie J B Vos

    Full Text Available BACKGROUND: Cerebrospinal fluid (CSF biomarkers are increasingly being used for diagnosis of Alzheimer's disease (AD. OBJECTIVE: We investigated the influence of CSF intralaboratory and interlaboratory variability on diagnostic CSF-based AD classification of subjects and identified causes of this variation. METHODS: We measured CSF amyloid-β (Aβ 1-42, total tau (t-tau, and phosphorylated tau (p-tau by INNOTEST enzyme-linked-immunosorbent assays (ELISA in a memory clinic population (n = 126. Samples were measured twice in a single or two laboratories that served as reference labs for CSF analyses in the Netherlands. Predefined cut-offs were used to classify CSF biomarkers as normal or abnormal/AD pattern. RESULTS: CSF intralaboratory variability was higher for Aβ1-42 than for t-tau and p-tau. Reanalysis led to a change in biomarker classification (normal vs. abnormal of 26% of the subjects based on Aβ1-42, 10% based on t-tau, and 29% based on p-tau. The changes in absolute biomarker concentrations were paralleled by a similar change in levels of internal control samples between different assay lots. CSF interlaboratory variability was higher for p-tau than for Aβ1-42 and t-tau, and reanalysis led to a change in biomarker classification of 12% of the subjects based on Aβ1-42, 1% based on t-tau, and 22% based on p-tau. CONCLUSIONS: Intralaboratory and interlaboratory CSF variability frequently led to change in diagnostic CSF-based AD classification for Aβ1-42 and p-tau. Lot-to-lot variation was a major cause of intralaboratory variability. This will have implications for the use of these biomarkers in clinical practice.

  7. Low CSF oxytocin reflects high intent in suicide attempters.

    Science.gov (United States)

    Jokinen, Jussi; Chatzittofis, Andreas; Hellström, Christer; Nordström, Peter; Uvnäs-Moberg, Kerstin; Asberg, Marie

    2012-04-01

    Data from animal studies suggest that oxytocin is an important modulating neuropeptide in regulation of social interaction. One human study has reported a negative correlation between CSF oxytocin levels, life history of aggression and suicidal behaviour. We hypothesized that CSF oxytocin levels would be related to suicidal behaviour, suicide intent, lifetime interpersonal violence and suicide risk. 28 medication free suicide attempters and 19 healthy volunteers participated in this cross sectional and longitudinal study. CSF and plasma morning basal levels of oxytocin were assessed with specific radio-immunoassays. The Beck Suicide Intent Scale (SIS), the Freeman scale and the Karolinska Interpersonal Violence Scale (KIVS) were used to assess suicide intent and lifetime violent behaviour. All patients were followed up for cause of death. The mean follow-up was 21 years. Suicide attempters had lower CSF oxytocin levels compared to healthy volunteers p=0.077. In suicide attempters CSF oxytocin showed a significant negative correlation with the planning subscale of SIS. CSF oxytocin showed a significant negative correlation with suicide intent, the planning subscale of SIS and Freeman interruption probability in male suicide attempters. Correlations between plasma oxytocin levels and the planning subscale of SIS and Freeman interruption probability were significant in male suicide attempters. Lifetime violent behaviour showed a trend to negative correlation with CSF oxytocin. In the regression analysis suicide intent remained a significant predictor of CSF oxytocin corrected for age and gender whereas lifetime violent behaviour showed a trend to be a predictor of CSF oxytocin. Oxytocin levels did not differ significantly in suicide victims compared to survivors. CSF oxytocin may be an important modulator of suicide intent and interpersonal violence in suicide attempters.

  8. Prediction and Monitoring Systems of Creep-Fracture Behavior of 9Cr-1Mo Steels for Teactor Pressure Vessels

    Energy Technology Data Exchange (ETDEWEB)

    Potirniche, Gabriel [Univ. of Idaho, Moscow, ID (United States); Barlow, Fred D. [Univ. of Idaho, Moscow, ID (United States); Charit, Indrajit [Univ. of Idaho, Moscow, ID (United States); Rink, Karl [Univ. of Idaho, Moscow, ID (United States)

    2013-11-26

    A recent workshop on next-generation nuclear plant (NGNP) topics underscored the need for research studies on the creep fracture behavior of two materials under consideration for reactor pressure vessel (RPV) applications: 9Cr-1Mo and SA-5XX steels. This research project will provide a fundamental understanding of creep fracture behavior of modified 9Cr-1Mo steel welds for through modeling and experimentation and will recommend a design for an RPV structural health monitoring system. Following are the specific objectives of this research project: Characterize metallurgical degradation in welded modified 9Cr-1Mo steel resulting from aging processes and creep service conditions; Perform creep tests and characterize the mechanisms of creep fracture process; Quantify how the microstructure degradation controls the creep strength of welded steel specimens; Perform finite element (FE) simulations using polycrystal plasticity to understand how grain texture affects the creep fracture properties of welds; Develop a microstructure-based creep fracture model to estimate RPVs service life; Manufacture small, prototypic, cylindrical pressure vessels, subject them to degradation by aging, and measure their leak rates; Simulate damage evolution in creep specimens by FE analyses; Develop a model that correlates gas leak rates from welded pressure vessels with the amount of microstructural damage; Perform large-scale FE simulations with a realistic microstructure to evaluate RPV performance at elevated temperatures and creep strength; Develop a fracture model for the structural integrity of RPVs subjected to creep loads; and Develop a plan for a non-destructive structural health monitoring technique and damage detection device for RPVs.

  9. Some practical issues in the design, monitoring and analysis of a sequential randomized trial in pressure sore prevention.

    Science.gov (United States)

    Brown, J; McElvenny, D; Nixon, J; Bainbridge, J; Mason, S

    2000-12-30

    A sequential double blind (assessor and patient) triangular design was used to compare the incidence of pressure sores following elective major surgery among patients lying on a standard foam mattress with those on a dry visco-elastic polymer pad during their operation. A total of 446 patients were recruited into the trial between 1994 and 1996. Interim analyses were carried out after 181 patients were entered into the trial and then subsequently after approximately every 100 patients recruited. The trial unexpectedly reached a stopping boundary at the first interim analysis, however the Independent Data Monitoring Committee recommended continuation of the trial. They were concerned that there was a need for a larger definitive trial and about an apparent treatment by centre interaction. They required a substudy to be undertaken to further validate the subjective endpoint, and that further sensitivity analyses of the main trail endpoint should be carried out in the second interim analysis. The trial was stopped at the third interim analysis when again a stopping boundary was crossed indicating that the gel pad was associated with significantly fewer pressure sores than the standard mattress (log odds ratio -0.7, (95 per cent confidence interval (CI), -1.28, -0.11), p=0.02) (estimate CI, p-value adjusted for group sequential conduct). The design, monitoring and analysis of this trial will be presented as an example of the practical problems or non-problems encountered for the local hospitals, for the trials unit, for the data monitoring committee and for the funding committee. Copyright 2000 John Wiley & Sons, Ltd.

  10. 家庭血压监测对社区高血压病人血压控制的价值探讨%The Change of Blood Pressure in Patients with Hypertension by Home Blood Pressure Monitoring

    Institute of Scientific and Technical Information of China (English)

    张仁汉; 芦娜; 李洪山; 黄超

    2013-01-01

    Objective: To observe the change of blood pressure, by means of home blood pressure monitoring in patients with hypertension. Method: 212 patients with hypertension were included to proceed home blood pressure monitoring for three months. The data of ambulatory blood pressure monitoring before and after the home blood pressure monitoring were recorded and analyzed. Result:After regular home blood pressure monitoring for three months, the 24h-systolic blood pressure, day systolic blood pressure, and night systolic blood pressure were depressed (P<0.05), and the day mean blood pressure and 24h mean blood pressure were lowered significantly(P<0.05). Conclusion:By means of regular home blood pressure monitoring, the total level of blood pressure are controlled lower in patients with hypertension. It is beneficial for improvement of controlling rate of hypertension and decreasing of complication.%  目的:观察家庭自测血压对高血压病人血压变化的影响。方法:212例门诊高血压病人经过家庭自测血压培训,进行规定的家庭血压监测,持续3个月,观察监测前后动态血压参数的变化。结果:与监测前相比,监测3个月后24h收缩压、白天收缩压、夜间收缩压均有明显降低(P<0.05);在监测3个月后白天平均压和24h平均压也有明显降低(P<0.05)。结论:通过规律的家庭自测血压,可使患者整体血压水平降低,从而有利于提高高血压的控制率和降低高血压的并发症。

  11. Experiments and analytical studies related to blowdown and containment thermal hydraulics on CSF

    Energy Technology Data Exchange (ETDEWEB)

    Dutta, Anu, E-mail: adutta@barc.gov.in; Thangamani, I.; Shanware, V.M.; Rao, K.S.; Gera, B.; Ravi Kiran, A.; Goyal, P.; Verma, Vishnu; Sharma, P.K.; Agrawal, M.K.; Ganju, S.; Singh, R.K.

    2015-12-01

    Highlights: • Blowdown and containment thermal hydraulics experiments conducted in CSF. • RELAP5, ASTEC and CONTRAN codes used for analysis. • Containment peak pressure and temp predicted close to experimental values. • CONTRAN and ASTEC codes predict early containment depressurization. • Numerical procedure, benchmarked for loss of coolant accident in nuclear reactors. - Abstract: Containment Studies Facility (CSF) is volumetrically scaled down model of Indian Pressurized Heavy Water Reactor (IPHWR) containment for simulating LOCA/MSLB conditions which consists of concrete containment model (CM) and Primary Heat Transport Model (PHTM) vessel. Blowdown experiments at different initial vessel pressure conditions were recently conducted at CSF and the vessel and containment parameters such as pressure, temperature and level transients have been recorded during the experiments. The experimental results have been used for benchmarking of numerical procedure adopted for evaluating LOCA/MSLB conditions in nuclear containment. The numerical procedure involves simulation of blowdown phenomena using RELAP5 code for evaluating mass and energy discharge rates, which are then used for calculating containment pressure–temperature transients using ASTEC and in-house CONTRAN codes. Predictions of major parameters of vessel and containment model were found to be in good agreement with that of experimental data. In containment thermal hydraulic calculations, condensation heat transfer coefficient affects the containment pressure–temperature transients. Various empirical condensation models like Tagami, Uchida and Diffusion models have been incorporated in CONTRAN code and suitable condensation model has been identified for which predicted pressure values are close to the experimental one. The details of the experimental and analytical studies conducted are presented in this paper.

  12. Late Onset of CSF Rhinorrhea in a Postoperative Transsphenoidal Surgery Patient Following Robotic-Assisted Abdominal Hysterectomy

    Directory of Open Access Journals (Sweden)

    Justin T. Dowdy MD

    2014-01-01

    Full Text Available Cerebrospinal fluid (CSF leak is the most commonly encountered perioperative complication in transsphenoidal surgery for pituitary lesions. Direct closure with a combination of autologous fat, local bone, and/or synthetic grafts remains the standard of care for leaks encountered at the time of surgery as well as postoperatively. The development of the vascularized nasoseptal flap as a closure technique has increased the surgeon’s capacity to correct even larger openings in the dura of the sella as well as widely exposed anterior skull base defects. Yet these advances in the technical nuances for management of post-transsphenoidal CSF leak are useless without the ability to recognize a CSF leak by physical examination, clinical history, biochemical testing, or radiographic assessment. Here, we report a case of a patient who developed a CSF leak 28 years after transsphenoidal surgery, precipitated by a robotic-assisted hysterectomy during which increased intra-abdominal pressure and steep Trendelenberg positioning were both factors. Given the remote nature of the patient’s transsphenoidal surgery and relative paucity of data regarding such a complication, the condition went unrecognized for several months. We review the available literature regarding risk and pathophysiology of CSF leak following abdominal surgery and propose the need for increased vigilance in identification of such occurrences with the increasing acceptance and popularity of minimally invasive abdominal and pelvic surgeries as standards in the field.

  13. Clinical experience with telemetric intracranial pressure monitoring in a Danish neurosurgical center

    DEFF Research Database (Denmark)

    Lilja, Alexander; Andresen, Morten; Hadi, Amer

    2014-01-01

    reading, number of ICP recording sessions (in relation to symptoms of increased ICP) and their clinical consequence. RESULTS: We included 21 patients in the evaluation (11 female and 10 male). Median age was 28 (2-83) years and median duration of disease was 11 (0-30) years. Eleven patients had various...... kinds of hydrocephalus, seven patients had idiopathic intracranial hypertension (IIH) and three patients had normal pressure hydrocephalus (NPH). Fifteen patients had a shunt prior to implantation. Median duration of implantation was 248 (49-666) days and median duration from implantation to last...

  14. Water content dynamics at plot scale - comparison of time-lapse electrical resistivity tomography monitoring and pore pressure modelling

    Science.gov (United States)

    Zieher, Thomas; Markart, Gerhard; Ottowitz, David; Römer, Alexander; Rutzinger, Martin; Meißl, Gertraud; Geitner, Clemens

    2017-01-01

    Physically-based dynamic modelling of shallow landslide susceptibility rests on several assumptions and simplifications. However, the applicability of physically-based models is only rarely tested in the field at the appropriate scale. This paper presents results of a spray irrigation experiment conducted on a plot of 100 m2 on an Alpine slope susceptible to shallow landsliding. Infiltrating precipitation applied at a constant rate (27.5 mm/h for 5.3 h) was monitored by means of 2D time-lapse electrical resistivity tomography, combined with time-domain reflectometry sensors installed at various depths. In addition, regolith characteristics were assessed by dynamic cone penetration tests using a light-weight cone penetrometer. The spray irrigation experiment resulted in a vertically progressing wetting front to a depth of 80-100 cm. Below that, the unconsolidated material was already saturated by rainfall in the previous days. The observed mean resistivity reduction attributed to infiltrating water during irrigation was scaled to pressure head. Mean variations in pore pressure were reproduced by a linear diffusion model also used in physically-based dynamic landslide susceptibility modelling. Sensitive parameters (hydraulic conductivity and specific storage) were tested over selected value ranges and calibrated. Calibrated parameter values are within published and experimentally derived ranges. The results of the comparison of observations and model results suggest that the model is capable of reproducing mean changes of pore pressure at a suitable scale for physically-based modelling of shallow landslide susceptibility. However, small-scale variations in pore pressure that may facilitate the triggering of shallow landslides are not captured by the model.

  15. Radial artery applanation tonometry for continuous noninvasive arterial blood pressure monitoring in the cardiac intensive care unit.

    Science.gov (United States)

    Langwieser, Nicolas; Prechtl, Luisa; Meidert, Agnes S; Hapfelmeier, Alexander; Bradaric, Christian; Ibrahim, Tareq; Laugwitz, Karl-Ludwig; Schmid, Roland M; Wagner, Julia Y; Saugel, Bernd

    2015-06-01

    Hemodynamic monitoring plays a pivotal role in the treatment of patients in the cardiac intensive care unit (CICU). The innovative radial artery applanation tonometry technology allows for continuous noninvasive arterial blood pressure (AP) measurement. By closing the gap between continuous invasive AP monitoring (arterial catheter) and intermittent noninvasive AP monitoring (oscillometry) this technology might improve CICU patient monitoring. We therefore aimed to evaluate the measurement performance of radial artery applanation tonometry in comparison with a radial arterial catheter in CICU patients. In this prospective method comparison study, we simultaneously recorded AP noninvasively with radial artery applanation tonometry (T-line 200 pro device; Tensys Medical Inc., San Diego, CA, USA) and invasively with an arterial catheter (criterion standard) in 30 patients treated in the CICU of a German university hospital. We statistically analyzed 7,304 averaged 10-beat epochs of measurements of mean AP, systolic AP, and diastolic AP by using Bland-Altman analysis for repeated measurements. Our study revealed a mean difference ± standard deviation (95% limits of agreement; percentage error) between radial artery applanation tonometry and the criterion standard method (radial arterial catheter) of +2 ± 6 mmHg (-10 to +14 mmHg; 17%) for mean AP, -6 ± 11 mmHg (-28 to +15 mmHg; 20%) for systolic AP, and +4 ± 7 mmHg (-9 to +17 mmHg; 23%) for diastolic AP. In CICU patients, continuous noninvasive measurement of AP using radial artery applanation tonometry is feasible. The technology showed reasonable accuracy and precision in comparison with radial arterial catheter-derived AP values.

  16. The rectenna design on contact lens for wireless powering of the active intraocular pressure monitoring system.

    Science.gov (United States)

    Cheng, H W; Jeng, B M; Chen, C Y; Huang, H Y; Chiou, J C; Luo, C H

    2013-01-01

    This paper proposed a wireless power harvesting system with micro-electro-mechanical-systems (MEMS) fabrication for noninvasive intraocular pressure (IOP) measurement on soft contact lens substructure. The power harvesting IC consists of a loop antenna, an impedance matching network and a rectifier. The proposed IC has been designed and fabricated by CMOS 0.18 um process that operates at the ISM band of 5.8 GHz. The antenna and the power harvesting IC would be bonded together by using flip chip bonding technologies without extra wire interference. The circuit utilized an impedance transformation circuit to boost the input RF signal that improves the circuit performance. The proposed design achieves an RF-to-DC conversion efficiency of 35% at 5.8 GHz.

  17. Ultrasonic Reflectometry for Monitoring the Effect of Pressure on Sludge Fouling of MF Membranes

    DEFF Research Database (Denmark)

    Jørgensen, Mads Koustrup; Kujundzic, Elmira; Greenberg, Alan

    as compared to a water-swollen layer at lower pressure. References 1. V. Chen, H. Li, A.G. Fane, J. Membr. Sci, 241, 23-44 (2004). 2. X.Y. Lu, E. Kujundzic, G. Mizrahi, J. Wang, K. Cobry, M. Peterson, J. Gilron, A. Greenberg, J. Membr Sci., 419, 20-32 (2012). 3. X.H. Li, J.X. Li, J. Wang, H.W. Zhang, Y.D. Pan......, J. Membr. Sci., 411, 137-145 (2012). 4. E. Kujundzic, A.R. Greenberg, R. Fong, B. Moore, D. Kujundzic, M. Hernandez, J. Membr. Sci., 349, 44-55 (2010). 5. E. Kujundzic, A.C. Fonseca, E.A. Evans, M. Peterson, A.R. Greenberg, M. Hernandez, J. Microbiol. Methods, 68, 458-467 (2007). 6. E. Kujundzic, A.......R. Greenberg and M. Peterson, Desalination and Water Treatment, DOI: 10.1080/19443994.2013.874132 (2014)....

  18. Validity of a wrist digital monitor for blood pressure measurement in comparison to a mercury sphygmomanometer

    OpenAIRE

    Menezes, Ana M. B.; Dumith,Samuel C.; Ricardo B. Noal; Ana Paula Nunes; Mendonça,Fernanda I.; Cora L. P. Araújo; Duval,Marta A.; Caruso,Paulo E.; Hallal, Pedro C.

    2010-01-01

    FUNDAMENTO: Medidas válidas da pressão arterial, em situações clínicas e na comunidade, são essenciais para a monitoração dessa variável em nível populacional. OBJETIVO: Avaliar a validade de um monitor digital de pulso para mensuração da pressão arterial em adolescentes, em comparação com um esfigmomanômetro de mercúrio. MÉTODOS: Um estudo de validação foi realizado na cidade de Pelotas, região sul do Brasil. A pressão arterial foi medida duas vezes, utilizando-se dois esfigmomanômetros dife...

  19. A new noninvasive device for continuous arterial blood pressure monitoring in the superficial temporal artery.

    Science.gov (United States)

    Chin, K Y; Panerai, R B

    2013-04-01

    Continuous recording of arterial blood pressure (ABP) has many applications in cardiovascular physiology, but existing alternatives rely on measurements performed in the fingers or radial artery. Peripheral recordings have significant differences from central ABP regarding the pattern of the waveform and corresponding systolic and diastolic values. To address the need for noninvasive measurements closer to the ascending aorta, a new device was constructed to measure ABP in the superficial temporal artery (STA) using photoplethysmography and the arterial volume clamping technique. The optoelectronic circuitry to generate the photoplethysmogram is contained in a specially designed probe placed over the STA and kept in place with a head frame. The prototype (STAbp) also includes original designs for the pneumatic, electronic, signal processing, control and display sub-systems. A self-calibration feature regularly updates the photoplethysmogram operating point to improve accuracy. The performance of the STAbp was compared against the Finapres in 19 healthy subjects. At rest, the bias (SDd) was -23.1 (15.05), -10.8 (13.83) and -12.4 (12.93) mmHg for systolic, mean and diastolic pressures respectively, without significant differences in drift between the two devices. The 99% bandwidth (SD) for the spectral distribution of ABP waveforms was 5.3 (1.46) Hz for STAbp and 6.8 (0.73) Hz for the Finapres (p < 0.01). Handgrip manoeuvre showed a very similar response to the Finapres, including the rapid return to baseline on release. The new STAbp device has considerable potential as a new tool for clinical and research applications where continuous recording of more central ABP is advantageous compared to peripheral alternatives.

  20. Office blood pressure, ambulatory blood pressure monitoring, and echocardiographic abnormalities in women with polycystic ovary syndrome: role of obesity and androgen excess.

    Science.gov (United States)

    Luque-Ramírez, Manuel; Martí, David; Fernández-Durán, Elena; Alpañés, Macarena; Álvarez-Blasco, Francisco; Escobar-Morreale, Héctor F

    2014-03-01

    Whether or not blood pressure (BP) and heart function of women with polycystic ovary syndrome (PCOS) are altered remains unclear, albeit subtle abnormalities in the regulation of BP observed in these women might suggest a mild masculinization of their cardiovascular system. To study the influence of obesity and androgen excess on BP and echocardiographic profiles of women with the syndrome, we conducted a cross-sectional case-control study comparing office and ambulatory BP monitoring, as well as echocardiographic assessments, in 63 premenopausal women with the classic phenotype, 33 nonhyperandrogenic women with regular menses, and 25 young men. Forty-nine subjects were lean and 72 had weight excess (body mass index ≥25 kg/m(2)). Participants had no previous history of hypertension and were nonsmokers. Men showed the highest BP readings, and the lowest readings were observed in control women, whereas women with PCOS had intermediate values. Undiagnosed hypertension was more common in subjects with weight excess irrespective of sex and hyperandrogenism. Women with PCOS and weight excess showed frequencies of previously undiagnosed hypertension that were similar to those of men with weight excess and higher than those observed in nonhyperandrogenic women. Lastly, male sex, weight excess and hypertension, the latter in men as well as in women with PCOS, increased left ventricular wall thickness. In summary, our results show that patients with classic PCOS and weight excess frequently have undiagnosed BP abnormalities, leading to target organ damage.

  1. 家庭血压监测中国专家共识%Home blood pressure monitoring: a consensus document of China

    Institute of Scientific and Technical Information of China (English)

    中国医师协会高血压专业委员会; 中国高血压联盟; 中华医学会心血管病学分会

    2012-01-01

    自动的电子血压计正在进入家庭.家庭血压监测已成为血压管理的重要组成部分.近年来,美国、欧洲与日本相继制定了家庭血压监测指南.我国家庭血压监测的研究工作正处起步阶段,尚不能完全根据我国相关研究的结果制定指南.随着高血压患者家庭血压压管理意识的迅速提高,许多家庭拥有了自动的电子血压计,同时也在进行家庭血压测量.为了促进家庭血压监测的健康发展,需要对家庭血压监测进行适当的规范.因此,参考国外有关指南并经广泛、深入的讨论,制定本共识文件.就血压计的选择与校准、血压测量的频率(次数)与时间(天数)以及家庭血压的正常值等重要问题提出了建议.%In China, automated blood pressure monitors recently have been available for home use. Home blood pressure monitoring plays a part in the management of hypertension. In the past few years, the American, European and Japanese societies of hypertension published their guidance document for home blood pressure monitoring. In China, there is still limited data on home blood pressure monitoring, which is insufficient to form a guidance document on the basis of the Chinese data. However, a proportion of Chinese hypertensive patients are becoming aware of the importance of home blood pressure monitoring, and measure blood pressure at home using automated blood pressure monitors. There is therefore a need of guidance- for home blood pressure monitoring. With the reference to the above mentioned guidelines of several other societies and after thorough and comprehensive discussions among a group of Chinese experts on hypertension, this consensus document was then developed to put forward recommendations on the selection and calibration of blood pressure measuring devices, the number of readings and days of blood pressure measurement, and the diagnostic threshold of home blood pressure.

  2. CSF cortisol in Alzheimer's disease and mild cognitive impairment.

    Science.gov (United States)

    Popp, Julius; Schaper, Karsten; Kölsch, Heike; Cvetanovska, Gabriela; Rommel, Fatima; Klingmüller, Dietrich; Dodel, Richard; Wüllner, Ullrich; Jessen, Frank

    2009-03-01

    Hypercortisolaemia occurs in Alzheimer's disease (AD) and may be involved in the AD related neurodegenerative process. In order to determine whether brain structures are exposed to high cortisol concentrations early in AD, we measured cerebrospinal fluid (CSF) cortisol in 66 subjects with AD, 33 subjects with mild cognitive impairment (MCI) and 34 control subjects. CSF cortisol concentrations were higher in AD subjects compared to controls (pcortisol in MCI subjects compared with controls suggesting that the increase of CSF cortisol is not an early event in the course of AD.

  3. CSF Ascites: Review of articles and a case presentation

    Directory of Open Access Journals (Sweden)

    R Pourkhalili

    2005-09-01

    Full Text Available Cerebrospinal fluid (CSF ascites is a rare complication after ventriculopritoneal (VP shunts. Most patients have gradual abdominal protrusion without any neurological sign or symptom of shunt malfunction. We presented a girl with posterior third ventricle glioblastoma and acute hydrocephalus who developed increasingly abdominal protrusion one month after VP shunt operation. Ascites fluid examination showed characteristic findings similar to CSF with no evidence of infection or malignant cells. Ventriculo-atrial shunt revision cured patient's ascites. Review articles of patients with CSF ascites after VP shunt were presented in details. Key words: Cerebrospinal fluid, Ascites, Ventriculopritoneal Shunt

  4. UPLC-MS/MS assay of riluzole in human plasma and cerebrospinal fluid (CSF): Application in samples from spinal cord injured patients.

    Science.gov (United States)

    Sarkar, Mahua; Grossman, Robert G; Toups, Elizabeth G; Chow, Diana S-L

    2017-09-01

    In the present study, a sensitive and robust LC-MS/MS method has been developed and validated for the quantification of riluzole in human plasma and cerebrospinal fluid (CSF) in clinical samples from patients with spinal cord injury (SCI). Riluzole and its labeled internal standard (IS) were isolated from plasma and CSF by liquid-liquid extraction using ethyl acetate. Riluzole (m/z 235→166) and IS (m/z 238→169) were detected by electrospray ionization (ESI) using multiple reaction monitoring (MRM) in a positive mode. The assay was linear in the concentration range of 0.5 (LLOQ, signal/noise ratio>10)-800ng/ml in plasma, and 1.0 (LLOQ)-800ng/ml in CSF samples. The intra- and inter-day accuracy in plasma were 94.2-110.0% and 97.8-102.0%, respectively, and those in CSF were 87.6-105.1% and 91.9-98.8%, respectively. The intra- and inter-day precision were 2.2-7.2% and 4.0-9.1%, respectively, in plasma, and 1.4-14.1% and 2.6-11.5%, respectively in CSF. Matrix effect was negligible from both matrices with signal percentages of 97.6-100.6% in plasma and 99.4-106.4% in CSF. The recoveries were >75% in plasma, >84% in CSF with low protein (53.9mg/dl), and >68% in CSF with high protein (348.2mg/dl). This method was successfully applied to quantify riluzole concentrations in plasma and CSF from patients with SCI. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. The effectiveness of a life style modification and peer support home blood pressure monitoring in control of hypertension: protocol for a cluster randomized controlled trial.

    Science.gov (United States)

    Su, Tin Tin; Majid, Hazreen Abdul; Nahar, Azmi Mohamed; Azizan, Nurul Ain; Hairi, Farizah Mohd; Thangiah, Nithiah; Dahlui, Maznah; Bulgiba, Awang; Murray, Liam J

    2014-01-01

    Death rates due to hypertension in low and middle income countr