Practices and opinions on nitrous oxide/oxygen sedation from dentists licensed to perform relative analgesia in Brazil

Directory of Open Access Journals (Sweden)

Daher Anelise

2012-07-01

Full Text Available Abstract Background Relative analgesia (RA, defined as the use of inhalation sedation with nitrous oxide and oxygen, is one of the most common pharmacological behavior management techniques used to provide sedation and analgesia for dental patients. This study aimed to assess RA licensed Brazilian dentists’ practices and opinions about nitrous oxide/oxygen sedation in the dental setting. Methods A cross sectional national survey was conducted with 281 dentists who were certified to perform RA, using an electronically mailed self-administered questionnaire containing closed questions about their practices and opinions regarding RA. Practice and opinion were individually analyzed by descriptive statistics. Non-parametric tests assessed the relationships between RA practice and independent variables. To test the interplay between practices and opinions, a k-means clusters analysis was used to divide the group for statistical comparisons. Results The response rate was 45.2%. Women made up 64.6% of the respondents, the mean age was 39.1 years (SD = 9.8, and the mean time since graduation in dentistry was 16 years (SD = 9.7. Seventy-seven percent of respondents reported the use of RA in clinical practice, most of them ‘sometimes’ (53.5%, and focusing more on adult patients. Patients with certain physical or mental deficiencies were indications associated with RA practice. ‘Equipment acquisition’ (p  Conclusion Most of the RA licensed Brazilian dentists interviewed currently use RA. Current practice of RA and frequency of use determined the degree of favorable opinion about this inhalation sedation among this group of respondents.

The effect of neuromuscular blockade on oxygen consumption in sedated and mechanically ventilated pediatric patients after cardiac surgery.

NARCIS (Netherlands)

Lemson, J.; Driessen, J.J.; Hoeven, J.G. van der

2008-01-01

OBJECTIVE: To measure the effect of intense neuromuscular blockade (NMB) on oxygen consumption (VO(2)) in deeply sedated and mechanically ventilated children on the first day after complex congenital cardiac surgery. DESIGN: Prospective clinical interventional study. SETTING: Pediatric intensive

Dynamic-Stability Characteristics of Premixed Methane Oxy-Combustion

KAUST Repository

Shroll, Andrew P.; Shanbhogue, Santosh J.; Ghoniem, Ahmed F.

2012-01-01

This work explores the dynamic stability characteristics of premixed CH 4/O 2/CO 2 mixtures in a 50 kW swirl stabilized combustor. In all cases, the methane-oxygen mixture is stoichiometric, with different dilution levels of carbon dioxide used

Supplementary Material for: Measurements of Positively Charged Ions in Premixed Methane-Oxygen Atmospheric Flames

KAUST Repository

Alquaity, Awad B. S.

2017-01-01

Cations and anions are formed as a result of chemi-ionization processes in combustion systems. Electric fields can be applied to reduce emissions and improve combustion efficiency by active control of the combustion process. Detailed flame ion chemistry models are needed to understand and predict the effect of external electric fields on combustion plasmas. In this work, a molecular beam mass spectrometer (MBMS) is utilized to measure ion concentration profiles in premixed methane–oxygen argon burner-stabilized atmospheric flames. Lean and stoichiometric flames are considered to assess the dependence of ion chemistry on flame stoichiometry. Relative ion concentration profiles are compared with numerical simulations using various temperature profiles, and good qualitative agreement was observed for the stoichiometric flame. However, for the lean flame, numerical simulations misrepresent the spatial distribution of selected ions greatly. Three modifications are suggested to enhance the ion mechanism and improve the agreement between experiments and simulations. The first two modifications comprise the addition of anion detachment reactions to increase anion recombination at low temperatures. The third modification involves restoring a detachment reaction to its original irreversible form. To our knowledge, this work presents the first detailed measurements of cations and flame temperature in canonical methane–oxygen-argon atmospheric flat flames. The positive ion profiles reported here may be useful to validate and improve ion chemistry models for methane-oxygen flames.

Sedation with nitrous oxide compared with no sedation during catheterization for urologic imaging in children

International Nuclear Information System (INIS)

Zier, Judith L.; Kvam, Kathryn A.; Kurachek, Stephen C.; Finkelstein, Marsha

2007-01-01

Various strategies to mitigate children's distress during voiding cystourethrography (VCUG) have been described. Sedation with nitrous oxide is comparable to that with oral midazolam for VCUG, but a side-by-side comparison of nitrous oxide sedation and routine care is lacking. The effects of sedation/analgesia using 70% nitrous oxide and routine care for VCUG and radionuclide cystography (RNC) were compared. A sample of 204 children 4-18 years of age scheduled for VCUG or RNC with sedation or routine care were enrolled in this prospective study. Nitrous oxide/oxygen (70%/30%) was administered during urethral catheterization to children in the sedated group. The outcomes recorded included observed distress using the Brief Behavioral Distress Score, self-reported pain, and time in department. The study included 204 patients (99 nonsedated, 105 sedated) with a median age of 6.3 years (range 4.0-15.2 years). Distress and pain scores were greater in nonsedated than in sedated patients (P < 0.001). Time in department was longer in the sedated group (90 min vs. 30 min); however, time from entry to catheterization in a non-imaging area accounted for most of the difference. There was no difference in radiologic imaging time. Sedation with nitrous oxide is effective in reducing distress and pain during catheterization for VCUG or RNC in children. (orig.)

An experimental and kinetic modeling study of premixed nitroethane flames at low pressure

DEFF Research Database (Denmark)

Zhang, Kuiwen; Zhang, Lidong; Xie, Mingfeng

2013-01-01

An experimental and kinetic modeling study is reported on three premixed nitroethane/oxygen/argon flames at low pressure (4.655kPa) with the equivalence ratios (Φ) of 1.0, 1.5 and 2.0. Over 30 flame species were identified with tunable synchrotron vacuum ultraviolet photoionization mass spectrome......An experimental and kinetic modeling study is reported on three premixed nitroethane/oxygen/argon flames at low pressure (4.655kPa) with the equivalence ratios (Φ) of 1.0, 1.5 and 2.0. Over 30 flame species were identified with tunable synchrotron vacuum ultraviolet photoionization mass...

Influence of the depth of sedation on regional cerebral oxygen saturation monitoring in neurosurgery of supratentorial gliomas

Directory of Open Access Journals (Sweden)

ZHANG Kai⁃ying

2012-12-01

Full Text Available Objective To investigate the influence on regional cerebral oxygen saturation (rScO2 of sedation depth during anesthesia induction and maintenance in supratentorial glioma resections. Methods Thirty patients with Ⅰ - Ⅱ supratentorial glioma (graded by American Society of Anesthesiologists underwent elective supratentorial glioma resection were included in this study. Rocuronium, sufentanil and propofol were used for anesthesia induction. After trachea cannula, total intravenous anesthesia (TIVA was maintained with plasma concentration of propofol 2.80-3.20 μg/ml and remifentanil 0.10-0.20 μg/(kg·min. Thirty groups of rScO2, bispectral index (BIS, mean arterial pressure (MAP and heart rate (HR were recorded continuously till the incision. Results During anesthesia induction, BIS decreased along with the infusion of anesthetics, and there was significant negative correlation between BIS and rScO2 (r = ⁃0.803, P = 0.001. During anesthesia maintenance, rScO2 and BIS were not significantly related (r = 0.147, P = 0.396. Conclusion The rScO2 monitoring can reflect the influence of sedation depth on cerebral oxygen delivery and consumption balance during supratentorial glioma resection under TIVA．

The PediSedate device, a novel approach to pediatric sedation that provides distraction and inhaled nitrous oxide: clinical evaluation in a large case series.

Science.gov (United States)

Denman, William T; Tuason, Pacifico M; Ahmed, Mohammed I; Brennen, Loralie M; Cepeda, M Soledad; Carr, Daniel B

2007-02-01

Pediatric sedation is of paramount importance but can be challenging. Fear and anticipatory anxiety before invasive procedures often lead to uncooperativeness. A novel device (PediSedate) provides sedation through a combination of inhaled nitrous oxide and distraction (video game). We evaluated the acceptability and safety of the PediSedate device in children. We enrolled children between 3 and 9 years old who were scheduled to undergo surgical procedures that required general inhalational anesthesia. After the device was applied, he/she played a video game while listening to the audio portion of the game through the earphones. Nitrous oxide in oxygen was administered via the nasal piece of the headset starting at 50% and increasing to 70%, in 10% increments every 8 min. Treatment failures, vital signs, arterial oxygen saturation, depth of sedation, airway patency, side effects, acceptance of the device and parental satisfaction were all evaluated. Of 100 children included, treatment failure occurred in 18% mainly because of poor tolerance of the device. At least 96% of the children who completed the study exhibited an excellent degree of sedation, 22% had side effects, and none experienced serious airway obstruction. Nausea and vomiting were the most common side effects and no patients had hemodynamic instability. The PediSedate device combines nonpharmacologic with pharmacologic methods of sedation. Most of the children we evaluated were able to tolerate the PediSedate device and achieved an adequate degree of sedation.

A retrospective study of deep sedation with concomitant administration of sedative agents in children undergoing surgical removal of a mesiodens.

Science.gov (United States)

Lee, Soo Jeong; Baek, Kwangwoo

2015-12-01

Pediatric dentists face challenges when young patients require a mesiodens extraction. General anesthesia may be a burden to the child as well as the parent due to dental fears and costs. The aim of this study was to evaluate oral and intravenous sedation in the outpatient setting as a safe and effective means of managing patients who require a mesiodens extraction. Records were reviewed retrospectively to find patients who underwent a mesiodens removal procedure from January 2013 to September 2014 in the Department of Pediatric Dentistry at Ajou University Hospital (Suwon, Gyeonggi-do, Republic of Korea). A total of 81 patients (62 male and 19 female) between 4 and 11 years of age (mean [± SD] 81.6 ± 14.1 months) were studied, with a mean weight of 22.9 ± 3.3 kg (16 kg to 30 kg). Vital signs, sedation drug dosage, and sedation time were studied. Mean doses of 63.7 ± 2.5 mg/kg chloral hydrate and 1.36 ± 0.22 mg/kg hydroxyzine were used for oral sedation. Nitrous oxide/oxygen was administrated for 40.0 ± 2.1 min. The mean dose of midazolam administered intravenously was 0.14 ± 0.06 mg/kg (2.38 ± 0.97 times). In all cases, the mesiodens was removed successfully. Intravenous sedation combined with oral sedation and nitrous oxide/oxygen inhalation can be an alternative to general anesthesia when administrated and monitored properly.

Simulated use of premixed 0.25% isoflurane in 50% nitrous oxide and 50% oxygen.

Science.gov (United States)

Ross, J A; Tunstall, M E

2002-12-01

Isoflurane (0.25%) in premixed nitrous oxide and oxygen, 50/50, v/v (IN(2)O), has been suggested for pain relief in labour. Possible phase separation of the mixture was studied during simulated administration. A sinusoidal pump set at stroke volume of 2 litres and a rate of 20-22 bpm and cycling for 1 min in three was used to simulate breathing during the painful contractions of labour. The temperature inside a 10-litre capacity cylinder did not drecrease sufficiently to cause separation of the gas mixture. Temperature in the demand valve decreased to -15.5 degrees C and this caused a small amount of liquid formation within the valve. Accordingly, the inspired concentration during the first breath of mixture in a cycle could be transiently as high as 0.55%. The concentration observed at the patient connection after the first breath varied between 0.17 and 0.28%. The system delivered a clinically acceptable performance although further development to avoid liquid condensation is needed.

Effects of music on sedation depth and sedative use during pediatric dental procedures.

Science.gov (United States)

Ozkalayci, Ozlem; Araz, Coskun; Cehreli, Sevi Burcak; Tirali, Resmiye Ebru; Kayhan, Zeynep

2016-11-01

The study aimed to investigate the effects of listening to music or providing sound isolation on the depth of sedation and need for sedatives in pediatric dental patients. Prospective, randomized, and controlled study. Tertiary, university hospital. In total, 180 pediatric patients, American Society of Anesthesiologists physical status I and II, who were scheduled for dental procedures of tooth extraction, filling, amputation, and root treatment. Patients were categorized into 3 groups: music, isolation, and control. During the procedures, the patients in the music group listened to Vivaldi's The Four Seasons violin concertos by sound-isolating headphones, whereas the patients in the isolation group wore the headphones but did not listen to music. All patients were sedated by 0.1 mg/kg midazolam and 1 mg/kg propofol. During the procedure, an additional 0.5 mg/kg propofol was administered as required. Bispectral index was used for quantifying the depth of sedation, and total dosage of the propofol was used for sedative requirements. The patients' heart rates, oxygen saturations, and Observer's Assessment of Alertness and Sedation Scale and bispectral index scores, which were monitored during the operation, were similar among the groups. In terms of the amount of propofol used, the groups were similar. Prolonged postoperative recovery cases were found to be significantly frequent in the control group, according to the recovery duration measurements (P = .004). Listening to music or providing sound isolation during pediatric dental interventions did not alter the sedation level, amount of medication, and hemodynamic variables significantly. This result might be due to the deep sedation levels reached during the procedures. However, listening to music and providing sound isolation might have contributed in shortening the postoperative recovery duration of the patients. Copyright © 2016 Elsevier Inc. All rights reserved.

Flashback resistant pre-mixer assembly

Science.gov (United States)

Laster, Walter R [Oviedo, FL; Gambacorta, Domenico [Oviedo, FL

2012-02-14

A pre-mixer assembly associated with a fuel supply system for mixing of air and fuel upstream from a main combustion zone in a gas turbine engine. The pre-mixer assembly includes a swirler assembly disposed about a fuel injector of the fuel supply system and a pre-mixer transition member. The swirler assembly includes a forward end defining an air inlet and an opposed aft end. The pre-mixer transition member has a forward end affixed to the aft end of the swirler assembly and an opposed aft end defining an outlet of the pre-mixer assembly. The aft end of the pre-mixer transition member is spaced from a base plate such that a gap is formed between the aft end of the pre-mixer transition member and the base plate for permitting a flow of purge air therethrough to increase a velocity of the air/fuel mixture exiting the pre-mixer assembly.

Optimum Drug Combinations for the Sedation of Growing Boars Prior to Castration

Science.gov (United States)

Lehmann, Heidi S.; Blache, Dominique; Drynan, Eleanor; Tshewang, Pema; Blignaut, David J. C.; Musk, Gabrielle C.

2017-01-01

Simple Summary Pigs are notoriously challenging patients. They are difficult to handle so the use of predictable and safe sedation techniques is required for husbandry and surgical procedures. Various combinations of sedative and analgesic drugs have been previously investigated in this species, though the combination of midazolam and detomidine with either butorphanol or morphine has not been reported for sedation in pigs. The use of these combinations was investigated in the context of adequate sedation to allow castration of boars with the aid of local anaesthetic infiltration. The combination of midazolam, detomidine with butorphanol provided a more reliable sedation combination than that including morphine. It is proposed that this combination of drugs would be useful for sedation during painful husbandry procedures in pigs. Abstract Juvenile male pigs were sedated for castration. Eight five-month old boars were sedated twice (two weeks apart) with a combination of detomidine (0.1 mg/kg), midazolam (0.2 mg/kg) and either butorphanol (0.2 mg/kg) (Group MDB, n = 8) or morphine (0.2 mg/kg) (Group MDM, n = 8) intramuscularly. The boars were positioned in lateral recumbency and lidocaine (200 mg total) was injected into the testicle and scrotal skin. Castration of a single testicle was performed on two occasions. Sedation and reaction (to positioning and surgery) scores, pulse rate, respiratory rate, haemoglobin oxygen saturation, body temperature, arterial blood gas parameters and the times to immobility and then recovery were recorded. Atipamezole was administered if spontaneous recovery was not evident within 60 min of sedative administration. Data were compared with either a paired-sample t-test or a Wilcoxon-Signed Rank Test. There was no difference in sedation score, body temperature, respiratory rate and haemoglobin oxygen saturation between MDB and MDM. Mild hypoxaemia was noted in both groups. There was less reaction to castration after MDB. The pulse rate

Laryngospasm With Apparent Aspiration During Sedation With Nitrous Oxide.

Science.gov (United States)

Babl, Franz E; Grindlay, Joanne; Barrett, Michael Joseph

2015-11-01

Nitrous oxide and oxygen mixture has become increasingly popular for the procedural sedation and analgesia of children in the emergency department. In general, nitrous oxide is regarded as a very safe agent according to large case series. We report a case of single-agent nitrous oxide sedation of a child, complicated by laryngospasm and radiographically confirmed bilateral upper lobe pulmonary opacities. Although rarely reported with parenteral sedative agents, laryngospasm and apparent aspiration has not been previously reported in isolated nitrous oxide sedation. This case highlights that, similar to other sedative agents, nitrous oxide administration also needs to be conducted by staff and in settings in which airway emergencies can be appropriately managed. Copyright © 2015 American College of Emergency Physicians. Published by Elsevier Inc. All rights reserved.

Turbulent piloted partially-premixed flames with varying levels of O2/N2: stability limits and PDF calculations

Science.gov (United States)

Juddoo, Mrinal; Masri, Assaad R.; Pope, Stephen B.

2011-12-01

This paper reports measured stability limits and PDF calculations of piloted, turbulent flames of compressed natural gas (CNG) partially-premixed with either pure oxygen, or with varying levels of O2/N2. Stability limits are presented for flames of CNG fuel premixed with up to 20% oxygen as well as CNG-O2-N2 fuel where the O2 content is varied from 8 to 22% by volume. Calculations are presented for (i) Sydney flame B [Masri et al. 1988] which uses pure CNG as well as flames B15 to B25 where the CNG is partially-premixed with 15-25% oxygen by volume, respectively and (ii) Sandia methane-air (1:3 by volume) flame E [Barlow et al. 2005] as well as new flames E15 and E25 that are partially-premixed with 'reconstituted air' where the O2 content in nitrogen is 15 and 25% by volume, respectively. The calculations solve a transported PDF of composition using a particle-based Monte Carlo method and employ the EMST mixing model as well as detailed chemical kinetics. The addition of oxygen to the fuel increases stability, shortens the flames, broadens the reaction zone, and shifts the stoichiometric mixture fraction towards the inner side of the jet. It is found that for pure CNG flames where the reaction zone is narrow (∼0.1 in mixture fraction space), the PDF calculations fail to reproduce the correct level of local extinction on approach to blow-off. A broadening in the reaction zone up to about 0.25 in mixture fraction space is needed for the PDF/EMST approach to be able to capture these finite-rate chemistry effects. It is also found that for the same level of partial premixing, increasing the O2/N2 ratio increases the maximum levels of CO and NO but shifts the peak to richer mixture fractions. Over the range of oxygenation investigated here, stability limits have shown to improve almost linearly with increasing oxygen levels in the fuel and with increasing the contribution of release rate from the pilot.

Extinction of laminar partially premixed flames

Energy Technology Data Exchange (ETDEWEB)

Aggarwal, Suresh K. [Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, 842 W. Taylor Street, Room 2039, MC-251, Chicago, IL 60607-7022 (United States)

2009-12-15

Flame extinction represents one of the classical phenomena in combustion science. It is important to a variety of combustion systems in transportation and power generation applications. Flame extinguishment studies are also motivated from the consideration of fire safety and suppression. Such studies have generally considered non-premixed and premixed flames, although fires can often originate in a partially premixed mode, i.e., fuel and oxidizer are partially premixed as they are transported to the reaction zone. Several recent investigations have considered this scenario and focused on the extinction of partially premixed flames (PPFs). Such flames have been described as hybrid flames possessing characteristics of both premixed and non-premixed flames. This paper provides a review of studies dealing with the extinction of PPFs, which represent a broad family of flames, including double, triple (tribrachial), and edge flames. Theoretical, numerical and experimental studies dealing with the extinction of such flames in coflow and counterflow configurations are discussed. Since these flames contain both premixed and non-premixed burning zones, a brief review of the dilution-induced extinction of premixed and non-premixed flames is also provided. For the coflow configuration, processes associated with flame liftoff and blowout are described. Since lifted non-premixed jet flames often contain a partially premixed or an edge-flame structure prior to blowout, the review also considers such flames. While the perspective of this review is broad focusing on the fundamental aspects of flame extinction and blowout, results mostly consider flame extinction caused by the addition of a flame suppressant, with relevance to fire suppression on earth and in space environment. With respect to the latter, the effect of gravity on the extinction of PPFs is discussed. Future research needs are identified. (author)

Current sedation and monitoring practice for colonoscopy: an International Observational Study (EPAGE)

DEFF Research Database (Denmark)

Froehlich, F; Harris, JK; Wietlisbach, V

2006-01-01

centers. Oxygen desaturation (LT /= 85 %) occurred in 5 % of patients, of whom 80 % were moderately sedated. On average, three staff members were involved in procedures. An anesthesiologist was present during 27 % of colonoscopies, and during 85 % of colonoscopies using deep sedation. CONCLUSIONS...

Safety of Conscious Sedation In Interventional Radiology

International Nuclear Information System (INIS)

Arepally, Aravind; Oechsle, Denise; Kirkwood, Sharon; Savader, Scott J.

2001-01-01

Purpose: To identify rates of adverse events associated with the use of conscious sedation in interventional radiology.Methods: In a 5-month period, prospective data were collected on patients undergoing conscious sedation for interventional radiology procedures (n = 594). Adverse events were categorized as respiratory, sedative, or major adverse events. Respiratory adverse events were those that required oral airway placement, ambu bag, or jaw thrust. Sedation adverse events were unresponsiveness, oxygen saturation less than 90%, use of flumazenil/naloxone, or agitation. Major adverse events were hypotension, intubation, CPR, or cardiac arrest. The frequency of adverse events for the five most common radiology procedures were determined.Results: The five most common procedures (total n = 541) were biliary tube placement/exchange (n = 182), tunneled catheter placement (n 135), diagnostic arteriography (n = 125), vascular interventions (n = 52), and other catheter insertions (n = 46). Rates for respiratory, sedation, and major adverse events were 4.7%, 4.2%, and 2.0%, respectively. The most frequent major adverse event was hypotension (2.0%). Biliary procedures had the highest rate of total adverse events (p < .05) and respiratory adverse events (p < .05).Conclusion: The frequency of adverse events is low with the use of conscious sedation during interventional procedures. The highest rates occurred during biliary interventions

Experiments for the premixing phase (PREMIX); Experimente zur Vorvermischungsphase (PREMIX)

Energy Technology Data Exchange (ETDEWEB)

Cherdron, W.; Huber, F.; Kaiser, A.; Schuetz, W.; Steinbrueck, M.; Will, H.

1995-08-01

In the PREMIX experiment, the premixing phenomena are studied by means of real high temperature melt jets. Jet fragmentation as well as (coarse) fragmentation of melt drops are being investigated. The objective is to avoid as far as possible a fine fragmentation and thus to help prevent explosions. Therefore water is used close to boiling temperature. The pressure can be varied in a relevant range up to nearly 10 bar. The melt is created by a thermite reaction after which most of the iron is separated from the melt. In this way a predominantly oxide melt with temperatures of about 2700 K is produced. Preliminary experiments showed as a surprising result that melt jets can penetrate into the water as far as nearly 1 m depth before a violant evaporation comes about. (orig.)

The impact of a standardised intramuscular sedation protocol for acute behavioural disturbance in the emergency department

Directory of Open Access Journals (Sweden)

Downes Michael A

2010-06-01

Full Text Available Abstract Background Acute behavioural disturbance (ABD is an increasing problem in emergency departments. This study aimed to determine the impact of a structured intramuscular (IM sedation protocol on the duration of ABD in the emergency department. Methods A historical control study was undertaken comparing 58 patients who required physical restraint and parenteral sedation with the structured IM sedation protocol, to 73 historical controls treated predominantly by intravenous sedation, according to individual clinician preference. The primary outcome was the duration of the ABD defined as the time security staff were required. Secondary outcomes were the requirement for additional sedation, drug related-adverse effects and patient and staff injuries. Results The median duration of the ABD in patients with the new sedation protocol was 21 minutes (IQR: 15 to 35 minutes; Range: 5 to 78 minutes compared to a median duration of 30 minutes (IQR: 15 to 50 minutes; Range: 5 to 135 minutes in the historical controls which was significantly different (p = 0.03. With IM sedation only 27 of 58 patients (47%; 95% CI: 34% to 60% required further sedation compared to 64 of 73 historical controls (88%; 95%CI: 77% to 94%. There were six (10% drug-related adverse events with the new IM protocol [oxygen desaturation (5, oxygen desaturation/airway obstruction (1] compared to 10 (14% in the historical controls [oxygen desaturation (5, hypoventilation (4 and aspiration (1]. Injuries to staff occurred with three patients using the new sedation protocol and in seven of the historical controls. Two patients were injured during the new protocol and two of the historical controls. Conclusion The use of a standardised IM sedation protocol was simple, more effective and as safe for management of ABD compared to predominantly intravenous sedation.

Large eddy simulation of premixed and non-premixed combustion

OpenAIRE

Malalasekera, W; Ibrahim, SS; Masri, AR; Sadasivuni, SK; Gubba, SR

2010-01-01

This paper summarises the authors experience in using the Large Eddy Simulation (LES) technique for the modelling of premixed and non-premixed combustion. The paper describes the application of LES based combustion modelling technique to two well defined experimental configurations where high quality data is available for validation. The large eddy simulation technique for the modelling flow and turbulence is based on the solution of governing equations for continuity and momentum in a struct...

Detection of Respiratory Adverse Events in Pediatric Dental Patients Sedated With 0.75mg/Kg of Midazolam and Oxygen by Continuous Pretracheal Auscultation: A Prospective Randomized Controlled Trial.

Science.gov (United States)

Somri, Mostafa; Matter, Ibrahim; Hadjittofi, Christopher; Hoash, Naser; Moaddi, Bian; Kharouba, Johnny; Parisinos, Constantinos A; Peretz, Benjamin

Sedation is becoming more commonplace for pediatric patients undergoing minor procedures. Fortunately, electronic monitors have contributed to a reduction in the associated respiratory adverse events (RAEs). To test the hypothesis that adding the pretracheal stethoscope (PTS) to standard monitoring methods (SMMs) may improve RAE detection in sedated pediatric dental patients, the frequency of RAEs detected by SMMs (i.e. visual observation, capnography, and pulse oximetry) was compared to that detected by SMMs alongside continuous PTS auscultation. A prospective, randomised, controlled trial was performed with 100 pediatric patient participants of ASA≤2, who were scheduled to receive dental treatment under 0.75 mg/kg and oxygen. Patients were randomised into Groups A (n=50; SMMs) and B (n=50; SMMs+PTS). Inclusion criteria were behavioral management problems and intolerance to dental treatment despite behavioral management techniques or nitrous oxide administration. Exclusion criteria were high-risk conditions for RAEs, altered mental status, gastrointestinal disorders, parental refusal of conscious sedation and failure of previous conscious sedation. An anesthesist was present throughout the dental treatments. RAEs were detected in 10 (20%) and 22(44%) Group A and B patients respectively (p=0.01). The majority of RAEs within Group B were detected by PTS auscultation (n=19). Capnography produced 13 and 15 false-positive results in Groups A and B respectively, whereas the PTS produced 4(8%) false-positive results in Group B (p=0.009). PTS was found to be useful for detecting RAEs during pediatric dental sedation with 0.75mg/kg midazolam and oxygen, in the presence of an anesthesist.

Effect of oxygenated fuel on premixed lean diesel combustion; Kihaku yokongo diesel nensho ni oyobosu gansanso nenryo kongo keiyu no eikyo

Energy Technology Data Exchange (ETDEWEB)

Sasaki, S.; Miyamoto, T.; Harada, A.; Akagawa, H.; Tsujimura, K. [New ACE Institute Co. Ltd., Tokyo (Japan)

1998-05-01

Because injection timing in diesel engines is early in a premixed lean diesel combustion system using early fuel injection, ignition timing is determined by ignitability of the fuel used. The conventional diesel fuel, which has good ignitability, causes excessively early ignition, thus aggravating fuel consumption. In order to reduce cylinder temperature with an aim of delaying ignition timing to improve the fuel consumption, attempts are being made on using low cetane fuels to reduce CO2 gas supply or compression ratio, and to vary ignitability of the fuels. The present study investigated ignition timing control and properties of exhausts by mixing different types of oxygenated fuels into light oil. Mixing the oxygenated fuels into light oil proved that the ignition timing can be controlled, and mixing such low cetane fuels as ethanol and MTBE achieved improvement in fuel consumption. Trial use of the oxygenated fuels aggravated CO concentration, which is caused because the cylinder temperature was reduced. Numerical calculations suggest that use of fuels with faster evaporation speed and lower cetane number is effective in improving the fuel consumption and the exhausts. 12 refs., 9 figs., 2 tabs.

Experiments for the premixing phase (PREMIX)

International Nuclear Information System (INIS)

Cherdron, W.; Huber, F.; Kaiser, A.; Schuetz, W.; Steinbrueck, M.; Will, H.

1995-01-01

In the PREMIX experiment, the premixing phenomena are studied by means of real high temperature melt jets. Jet fragmentation as well as (coarse) fragmentation of melt drops are being investigated. The objective is to avoid as far as possible a fine fragmentation and thus to help prevent explosions. Therefore water is used close to boiling temperature. The pressure can be varied in a relevant range up to nearly 10 bar. The melt is created by a thermite reaction after which most of the iron is separated from the melt. In this way a predominantly oxide melt with temperatures of about 2700 K is produced. Preliminary experiments showed as a surprising result that melt jets can penetrate into the water as far as nearly 1 m depth before a violant evaporation comes about. (orig.)

The impact of obesity on pediatric procedural sedation-related outcomes: results from the Pediatric Sedation Research Consortium.

Science.gov (United States)

Scherrer, Patricia D; Mallory, Michael D; Cravero, Joseph P; Lowrie, Lia; Hertzog, James H; Berkenbosch, John W

2015-07-01

To evaluate the impact of obesity on adverse events and required interventions during pediatric procedural sedation. The Pediatric Sedation Research Consortium database of prospectively collected procedural sedation encounters was queried to identify patients for whom body mass index (BMI) could be calculated. Obesity was defined as BMI ≥95th percentile for age and gender. Sedation-related outcomes, adverse events, and therapeutic interventions were compared between obese and nonobese patients. For analysis, 28,792 records were eligible. A total of 5,153 patients (17.9%) were obese; they were predominantly male and older and had a higher median American Society of Anesthesiologists Physical Status classification (P obese patients (odds ratio [OR] 1.49, 95% confidence interval [1.31, 1.70]). Respiratory events (airway obstruction OR 1.94 [1.54, 2.44], oxygen desaturation OR 1.99 [1.50, 2.63], secretions OR 1.48 [1.01, 2.15], laryngospasm OR 2.30 [1.30, 4.05]), inability to complete the associated procedure (OR 1.96 [1.16, 3.30]), and prolonged recovery (OR 2.66 [1.26, 5.59]) were increased in obese patients. Obese patients more frequently required airway intervention including repositioning, suctioning, jaw thrust, airway adjuncts, and bag-valve-mask ventilation. Multivariate regression analysis demonstrated obesity to be independently associated with minor and moderate but not major adverse events. Obesity is an independent risk factor for adverse respiratory events during procedural sedation and is associated with an increased frequency of airway interventions, suggesting that additional vigilance and expertise are required when sedating these patients. © 2015 John Wiley & Sons Ltd.

An experimental and kinetic modeling study of premixed nitromethane flames at low pressure

DEFF Research Database (Denmark)

Zhang, Kuiwen; Li, Yuyang; Yuan, Tao

2011-01-01

An experimental and modeling study is reported on three premixed nitromethane/oxygen/argon flames at low pressure (4.655kPa) with equivalence ratios (ϕ) of 1.0, 1.5 and 2.0. Flame species were identified with tunable synchrotron vacuum ultraviolet photoionization. The mole fraction profiles of more...

Capnography monitoring during procedural sedation and analgesia: a systematic review protocol

OpenAIRE

Conway, Aaron; Douglas, Clint; Sutherland, Joanna

2015-01-01

Background An important potential clinical benefit of using capnography monitoring during procedural sedation and analgesia (PSA) is that this technology could improve patient safety by reducing serious sedation-related adverse events, such as death or permanent neurological disability, which are caused by inadequate oxygenation. The hypothesis is that earlier identification of respiratory depression using capnography leads to a change in clinical management that prevents hypoxaemia. As inade...

Comparative study of non-premixed and partially-premixed combustion simulations in a realistic Tay model combustor

OpenAIRE

Zhang, K.; Ghobadian, A.; Nouri, J. M.

2017-01-01

A comparative study of two combustion models based on non-premixed assumption and partially premixed assumptions using the overall models of Zimont Turbulent Flame Speed Closure Method (ZTFSC) and Extended Coherent Flamelet Method (ECFM) are conducted through Reynolds stress turbulence modelling of Tay model gas turbine combustor for the first time. The Tay model combustor retains all essential features of a realistic gas turbine combustor. It is seen that the non-premixed combustion model fa...

Palliative sedation: reliability and validity of sedation scales.

Science.gov (United States)

Arevalo, Jimmy J; Brinkkemper, Tijn; van der Heide, Agnes; Rietjens, Judith A; Ribbe, Miel; Deliens, Luc; Loer, Stephan A; Zuurmond, Wouter W A; Perez, Roberto S G M

2012-11-01

Observer-based sedation scales have been used to provide a measurable estimate of the comfort of nonalert patients in palliative sedation. However, their usefulness and appropriateness in this setting has not been demonstrated. To study the reliability and validity of observer-based sedation scales in palliative sedation. A prospective evaluation of 54 patients under intermittent or continuous sedation with four sedation scales was performed by 52 nurses. Included scales were the Minnesota Sedation Assessment Tool (MSAT), Richmond Agitation-Sedation Scale (RASS), Vancouver Interaction and Calmness Scale (VICS), and a sedation score proposed in the Guideline for Palliative Sedation of the Royal Dutch Medical Association (KNMG). Inter-rater reliability was tested with the intraclass correlation coefficient (ICC) and Cohen's kappa coefficient. Correlations between the scales using Spearman's rho tested concurrent validity. We also examined construct, discriminative, and evaluative validity. In addition, nurses completed a user-friendliness survey. Overall moderate to high inter-rater reliability was found for the VICS interaction subscale (ICC = 0.85), RASS (ICC = 0.73), and KNMG (ICC = 0.71). The largest correlation between scales was found for the RASS and KNMG (rho = 0.836). All scales showed discriminative and evaluative validity, except for the MSAT motor subscale and VICS calmness subscale. Finally, the RASS was less time consuming, clearer, and easier to use than the MSAT and VICS. The RASS and KNMG scales stand as the most reliable and valid among the evaluated scales. In addition, the RASS was less time consuming, clearer, and easier to use than the MSAT and VICS. Further research is needed to evaluate the impact of the scales on better symptom control and patient comfort. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

A NEW DOUBLE-SLIT CURVED WALL-JET (CWJ) BURNER FOR STABILIZING TURBULENT PREMIXED AND NON-PREMIXED FLAMES

KAUST Repository

Mansour, Morkous S.; Chung, Suk-Ho

2015-01-01

Mixing characteristics in the cold flow of non-premixed cases were first examined using acetone fluorescence technique, indicating substantial transport between the fuel and air by exhibiting appreciable premixing conditions.PIV measurements revealed that velocity gradients in the shear layers at the boundaries of the annularjets generate the turbulence, enhanced with the collisions in the interaction jet, IJ,region. Turbulent mean and rms velocities were influenced significantly by Re and high rms turbulent velocities are generated within the recirculation zone improving the flame stabilization in this burner.Premixed and non-premixed flames with high equivalence ratio were found to be more resistant to local extinction and exhibited a more corrugated and folded nature, particularly at high Re. For flames with low equivalence ratio, the processes of local quenching at IJ region and of re-ignition within merged jet region maintained these flames further downstream particularly for non-premixed methane flame, revealing a strong intermittency.

Optimization of Premix Powders for Tableting Use.

Science.gov (United States)

Todo, Hiroaki; Sato, Kazuki; Takayama, Kozo; Sugibayashi, Kenji

2018-05-08

Direct compression is a popular choice as it provides the simplest way to prepare the tablet. It can be easily adopted when the active pharmaceutical ingredient (API) is unstable in water or to thermal drying. An optimal formulation of preliminary mixed powders (premix powders) is beneficial if prepared in advance for tableting use. The aim of this study was to find the optimal formulation of the premix powders composed of lactose (LAC), cornstarch (CS), and microcrystalline cellulose (MCC) by using statistical techniques. Based on the "Quality by Design" concept, a (3,3)-simplex lattice design consisting of three components, LAC, CS, and MCC was employed to prepare the model premix powders. Response surface method incorporating a thin-plate spline interpolation (RSM-S) was applied for estimation of the optimum premix powders for tableting use. The effect of tablet shape identified by the surface curvature on the optimization was investigated. The optimum premix powder was effective when the premix was applied to a small quantity of API, although the function of premix was limited in the case of the formulation of large amount of API. Statistical techniques are valuable to exploit new functions of well-known materials such as LAC, CS, and MCC.

Gas turbine premixing systems

Science.gov (United States)

Kraemer, Gilbert Otto; Varatharajan, Balachandar; Evulet, Andrei Tristan; Yilmaz, Ertan; Lacy, Benjamin Paul

2013-12-31

Methods and systems are provided for premixing combustion fuel and air within gas turbines. In one embodiment, a combustor includes an upstream mixing panel configured to direct compressed air and combustion fuel through premixing zone to form a fuel-air mixture. The combustor includes a downstream mixing panel configured to mix additional combustion fuel with the fule-air mixture to form a combustion mixture.

An experimental study on the effects of swirling oxidizer flow and diameter of fuel nozzle on behaviour and light emittance of propane-oxygen non-premixed flame

Directory of Open Access Journals (Sweden)

Javareshkian Alireza

2017-01-01

Full Text Available In this study, the stability and the light emittance of non-premixed propane-oxygen flames have been experimentally evaluated with respect to swirling oxidizer flow and variations in fuel nozzle diameter. Hence, three types of the vanes with the swirl angles of 30°, 45°, and 60° have been chosen for producing the desired swirling flows. The main aims of this study are to determine the flame behaviour, light emittance, and also considering the effect of variation in fuel nozzle diameter on combustion phenomena such as flame length, flame shape, and soot free length parameter. The investigation into the flame phenomenology was comprised of variations of the oxidizer and fuel flow velocities (respective Reynolds numbers and the fuel nozzle diameter. The results showed that the swirl effect could change the flame luminosity and this way could reduce or increase the maximum value of the flame light emittance in the combustion zone. Therefore, investigation into the flame light emittance can give a good clue for studying the mixing quality of reactants, the flame phenomenology (blue flame or sooty flame, localized extinction, and the combustion intensity in non-premixed flames.

Procedural sedation analgesia

Directory of Open Access Journals (Sweden)

Sheta Saad

2010-01-01

Full Text Available The number of noninvasive and minimally invasive procedures performed outside of the operating room has grown exponentially over the last several decades. Sedation, analgesia, or both may be needed for many of these interventional or diagnostic procedures. Individualized care is important when determining if a patient requires procedural sedation analgesia (PSA. The patient might need an anti-anxiety drug, pain medicine, immobilization, simple reassurance, or a combination of these interventions. The goals of PSA in four different multidisciplinary practices namely; emergency, dentistry, radiology and gastrointestinal endoscopy are discussed in this review article. Some procedures are painful, others painless. Therefore, goals of PSA vary widely. Sedation management can range from minimal sedation, to the extent of minimal anesthesia. Procedural sedation in emergency department (ED usually requires combinations of multiple agents to reach desired effects of analgesia plus anxiolysis. However, in dental practice, moderate sedation analgesia (known to the dentists as conscious sedation is usually what is required. It is usually most effective with the combined use of local anesthesia. The mainstay of success for painless imaging is absolute immobility. Immobility can be achieved by deep sedation or minimal anesthesia. On the other hand, moderate sedation, deep sedation, minimal anesthesia and conventional general anesthesia can be all utilized for management of gastrointestinal endoscopy.

A NEW DOUBLE-SLIT CURVED WALL-JET (CWJ) BURNER FOR STABILIZING TURBULENT PREMIXED AND NON-PREMIXED FLAMES

KAUST Repository

Mansour, Morkous S.

2015-06-30

A novel double-slit curved wall-jet (CWJ) burner was proposed and employed, which utilizes the Coanda effect by supplying fuel and air as annular-inward jets over a curved surface. We investigated the stabilization characteristics and structure of methane/air, and propane/air turbulent premixed and non-premixed flames with varying global equivalence ratio, , and Reynolds number, Re. Simultaneous time-resolved measurements of particle image velocimetry and planar laser-induced fluorescence of OH radicals were conducted. The burner showed potential for stable operation for methane flames with relatively large fuel loading and overall rich conditions. These have a non-sooting nature. However, propane flames exhibit stable mode for a wider range of equivalence ratio and Re. Mixing characteristics in the cold flow of non-premixed cases were first examined using acetone fluorescence technique, indicating substantial transport between the fuel and air by exhibiting appreciable premixing conditions.PIV measurements revealed that velocity gradients in the shear layers at the boundaries of the annularjets generate the turbulence, enhanced with the collisions in the interaction jet, IJ,region. Turbulent mean and rms velocities were influenced significantly by Re and high rms turbulent velocities are generated within the recirculation zone improving the flame stabilization in this burner.Premixed and non-premixed flames with high equivalence ratio were found to be more resistant to local extinction and exhibited a more corrugated and folded nature, particularly at high Re. For flames with low equivalence ratio, the processes of local quenching at IJ region and of re-ignition within merged jet region maintained these flames further downstream particularly for non-premixed methane flame, revealing a strong intermittency.

Use of high-flow nasal cannula in obese patients receiving colonoscopy under intravenous propofol sedation: A case series

Directory of Open Access Journals (Sweden)

Chi Chan Lee

Full Text Available Intravenous sedation during colonoscopy has become the standard practice in the United States given its higher patient satisfaction and procedural quality. This practice is not free of side effects as a significant proportion of patients undergoing this procedure tend to have respiratory depression and desaturation events. Obesity, as it relates to higher levels of body mass index (BMI has a positive correlation with the incidence of hypoxemia. During colonoscopy High flow nasal cannula (HFNC may potentially improve oxygen performance in patients receiving colonoscopy under intravenous sedation. Here we present 3 cases of patients undergoing adjunctive oxygen therapy with HFNC during colonoscopy with intravenous sedation. We found patients to have lower number of desaturation events and were satisfied with their experience. Keywords: High BMI (body mass index, HFNC (high-flow nasal cannula, Colonoscopy, Intravenous sedation, Obesity

Comparison of propofol deep sedation versus moderate sedation during endosonography.

Science.gov (United States)

Nayar, D S; Guthrie, W G; Goodman, A; Lee, Y; Feuerman, M; Scheinberg, L; Gress, F G

2010-09-01

The purposes of this study are: (1) to prospectively evaluate clinically relevant outcomes including sedation-related complications for endoscopic ultrasound (EUS) procedures performed with the use of propofol deep sedation administered by monitored anesthesia care (MAC), and (2) to compare these results with a historical case-control cohort of EUS procedures performed using moderate sedation provided by the gastrointestinal (GI) endoscopist. Patients referred for EUS between January 1, 2001 and December 31, 2002 were enrolled. Complication rates for EUS using MAC sedation were observed and also compared with a historical case-control cohort of EUS patients who received meperidine/midazolam for moderate sedation, administered by the GI endoscopist. Logistic regression analysis was used to isolate possible predictors of complications. A total of 1,000 patients underwent EUS with propofol sedation during the period from January 1, 2001 through December 31, 2002 (mean age 64 years, 53% female). The distribution of EUS indications based on the primary area of interest was: 170 gastroduodenal, 92 anorectal, 508 pancreaticohepatobiliary, 183 esophageal, and 47 mediastinal. The primary endpoint of the study was development of sedation-related complications occurring during a performed procedure. A total of six patients experienced complications: duodenal perforation (one), hypotension (one), aspiration pneumonia (one), and apnea requiring endotracheal intubation (three). The complication rate with propofol was 0.60%, compared with 1% for the historical case-control (meperidine/midazolam moderate sedation) group. There does not appear to be a significant difference between complication rates for propofol deep sedation with MAC and meperidine/midazolam administered for moderate sedation.

Premixed and non-premixed generated manifolds in large-eddy simulation of Sandia flame D and F

NARCIS (Netherlands)

Vreman, A.W.; Albrecht, B.A.; Oijen, van J.A.; Goey, de L.P.H.; Bastiaans, R.J.M.

2008-01-01

Premixed and nonpremixed flamelet-generated manifolds have been constructed and applied to large-eddy simulation of the piloted partially premixed turbulent flames Sandia Flame D and F. In both manifolds the chemistry is parameterized as a function of the mixture fraction and a progress variable.

Sedation and Anesthesia in Pediatric and Congenital Cardiac Catheterization: A Prospective Multicenter Experience.

Science.gov (United States)

Lin, C Huie; Desai, Sanyukta; Nicolas, Ramzi; Gauvreau, Kimberlee; Foerster, Susan; Sharma, Anshuman; Armsby, Laurie; Marshall, Audrey C; Odegard, Kirsten; DiNardo, James; Vincent, Julie; El-Said, Howaida; Spaeth, James; Goldstein, Bryan; Holzer, Ralf; Kreutzer, Jackie; Balzer, David; Bergersen, Lisa

2015-10-01

Sedation/anesthesia is critical to cardiac catheterization in the pediatric/congenital heart patient. We sought to identify current sedation/anesthesia practices, the serious adverse event rate related to airway, sedation, or anesthesia, and the rate of intra-procedural conversion from procedural sedation to the use of assisted ventilation or an artificial airway. Data from 13,611 patients who underwent catheterization at eight institutions were prospectively collected from 2007 to 2010. Ninety-four (0.69 %) serious sedation/airway-related adverse events occurred; events were more likely to occur in smaller patients (anesthesia, LMA, or tracheostomy, whereas 4232 (31 %) were managed with procedural sedation without an artificial airway, of which 75 (1.77 %) patients were converted to assisted ventilation/general anesthesia. Young age (risk procedure (category 4, OR 10.1, 95 % CI 6.5-15.6, p pediatric/congenital patients was associated with a low rate of serious sedation/airway-related adverse events. Smaller patients with non-cardiac comorbidities or low mixed venous oxygen saturation may be at higher risk. Patients under 1 year of age, undergoing high-risk procedures, or requiring continuous pressor/inotrope support may be at higher risk of requiring conversion from procedural sedation to assisted ventilation/general anesthesia.

Multidimensional flamelet-generated manifolds for partially premixed combustion

Energy Technology Data Exchange (ETDEWEB)

Nguyen, Phuc-Danh; Vervisch, Luc; Subramanian, Vallinayagam; Domingo, Pascale [CORIA - CNRS and INSA de Rouen, Technopole du Madrillet, BP 8, 76801 Saint-Etienne-du-Rouvray (France)

2010-01-15

Flamelet-generated manifolds have been restricted so far to premixed or diffusion flame archetypes, even though the resulting tables have been applied to nonpremixed and partially premixed flame simulations. By using a projection of the full set of mass conservation species balance equations into a restricted subset of the composition space, unsteady multidimensional flamelet governing equations are derived from first principles, under given hypotheses. During the projection, as in usual one-dimensional flamelets, the tangential strain rate of scalar isosurfaces is expressed in the form of the scalar dissipation rates of the control parameters of the multidimensional flamelet-generated manifold (MFM), which is tested in its five-dimensional form for partially premixed combustion, with two composition space directions and three scalar dissipation rates. It is shown that strain-rate-induced effects can hardly be fully neglected in chemistry tabulation of partially premixed combustion, because of fluxes across iso-equivalence-ratio and iso-progress-of-reaction surfaces. This is illustrated by comparing the 5D flamelet-generated manifold with one-dimensional premixed flame and unsteady strained diffusion flame composition space trajectories. The formal links between the asymptotic behavior of MFM and stratified flame, weakly varying partially premixed front, triple-flame, premixed and nonpremixed edge flames are also evidenced. (author)

Administration order of midazolam/fentanyl for moderate dental sedation.

Science.gov (United States)

Lobb, Douglas; Clarke, Alix; Lai, Hollis

2018-02-01

The purpose of this study is to investigate the effects of administration order when a sedative drug (midazolam) and an opioid analgesic drug (fentanyl) is applied for moderate intravenous (IV) sedation in dentistry. A retrospective chart review was conducted in one dental clinic during its transition from a midazolam-first to a fentanyl-first protocol for dental procedures requiring moderate IV sedation. Physiological parameters, drug administration times, patient recovery times, drug dosages, and patient recall and satisfaction were investigated for differences. A total of 76 charts (40 midazolam-first and 36 fentanyl-first administrations), were used in the analysis. Administering midazolam first resulted in an average 4.38 min (52%) decrease in administration times (P 0.05). Oxygen saturation levels did not drop below 90% for either group; however, 5 cases in the fentanyl-first group fell to between 90% and 92%, compared with 0 cases in the midazolam-first group. The administration order of fentanyl and midazolam may have different effects on patients and the sedation procedure. Findings from this study should be used to facilitate discussion among dental practitioners and to guide additional research investigating this topic.

Intravenous ketamine is as effective as midazolam/fentanyl for procedural sedation and analgesia in the emergency department.

Science.gov (United States)

Jamal, S M; Fathil, S M; Nidzwani, M M; Ismail, A K; Yatim, F M

2011-08-01

The study compared the effectiveness of ketamine and midazolam/fentanyl as procedural sedation and analgesia agents for reduction of fractures and dislocated joints. Forty-one adult patients were enrolled by convenience sampling. They were randomized to receive ketamine or midazolam/fentanyl. Depth of sedation, pain score, procedural outcome and memory of the procedure were documented. The ketamine group had deeper sedation, but there was no statistical difference in other variables between the two groups. Three patients in the midazolam/fentanyl group had oxygen desaturation. More adverse effects were associated with ketamine. Intravenous ketamine is as effective as midazolam/fentanyl for procedural sedation.

THE EFFECTS OF EQUIVALENCE RATIO ON THE FORMATION OF POLYCYCLIC AROMATIC HYDROCARBONS AND SOOT IN PREMIXED ETHANE FLAMES. (R825412)

Science.gov (United States)

AbstractThe formation of polycyclic aromatic hydrocarbons (PAH) and soot has been investigated in atmospheric-pressure, laminar, ethane/oxygen/argon premixed flames as a function of mixture equivalence ratio. Mole fraction profiles of major products, trace aromatics, ...

Cardiovascular, respiratory and sedative effects of intramuscular alfaxalone, butorphanol and dexmedetomidine compared with ketamine, butorphanol and dexmedetomidine in healthy cats.

Science.gov (United States)

Cremer, Jeannette; Riccó, Carolina H

2017-11-01

Objectives The aim of the study was to evaluate the cardiorespiratory effects, quality of sedation and recovery of intramuscular alfaxalone-dexmedetomidine-butorphanol (ADB) and ketamine-dexmedetomidine-butorphanol (KDB), in cats. Methods Nine adult, healthy cats (6.63 ± 1.42 kg) were enrolled in a blinded, randomized, crossover experimental design. Cats were sedated twice intramuscularly, once with ADB (alfaxalone 1 mg/kg, dexmedetomidine 0.005 mg/kg, butorphanol 0.2 mg/kg), and once with KDB (ketamine 5 mg/kg, dexmedetomidine 0.005 mg/kg, butorphanol 0.2 mg/kg), in random order. Data collected included heart rate (HR), arterial blood pressure and blood gas analysis, respiratory rate, and sedation score. Analysis of variance with Bonferroni post-hoc correction was used for parametric data, and a Wilcoxon signed rank test was used for non-parametric data. Significance was set at P <0.05. Results Total sedation time was shorter for ADB (90.71 ± 15.12 mins vs 147.00 ± 47.75 mins). Peak sedation was observed within 15 mins in both groups. Quality of recovery was excellent in both groups. HR decreased over time in both groups. Diastolic and mean arterial pressure decreased over time for ADB, becoming significant after 30 mins. All cardiovascular variables were within the clinically acceptable range in both groups. Arterial partial pressure of oxygen was significantly decreased from baseline for KDB at all time points (73 ± 2.5 mmHg [9.7 ± 0.3 kPa] vs ADB 83 ± 2.6 mmHg [11 ± 0.3 kPa]). Hypoventilation was not observed. Conclusions and relevance Both protocols produced acceptable cardiovascular stability. Sedation and recovery quality were good, albeit sedation was shorter with ADB. Although oxygenation was better maintained in the ADB group, all sedated cats should receive oxygen supplementation.

Anxiety in Children Undergoing VCUG: Sedation or No Sedation?

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David W. Herd

2008-01-01

Full Text Available Background. Voiding cystourethrograms are distressing for children and parents. Nonpharmacological methods reduce distress. Pharmacological interventions for VCUG focus on sedation as well as analgesia, anxiolysis, and amnesia. Sedation has cost, time, and safety issues. Which agents and route should we use? Are we sure that sedation does not influence the ability to diagnose vesicoureteric reflux? Methods. Literature search of Medline, EMBASE, and the Cochrane Database. Review of comparative studies found. Results. Seven comparative studies including two randomised controlled trials were reviewed. Midazolam given orally (0.5-0.6 mg/kg or intranasally (0.2 mg/kg is effective with no apparent effect on voiding dynamics. Insufficient evidence to recommend other sedating agents was found. Deeper sedating agents may interfere with voiding dynamics. Conclusion. Midazolam reduces the VCUG distress, causes amnesia, and does not appear to interfere with voiding dynamics. Midazolam combined with simple analgesia is an effective method to reduce distress to children undergoing VCUG.

Evaluation of nitrous oxide inhalation sedation during inferior alveolar block administration in children aged 7-10 years: A randomized control trial

Directory of Open Access Journals (Sweden)

Deepti Takkar

2015-01-01

Full Text Available Background: Nitrous oxide-oxygen (N 2 O-O 2 is being used in combination with many drugs and this possess risk for leading to deep sedation or reflexes being compromised. Aim: The purpose of our study was to use N 2 O-O 2 alone, to evaluate its effectiveness for pain control during inferior alveolar nerve block administration in children. Design: This was a single-centered, simple randomized, double-blinded, placebo-controlled parallel-group study involving 40 children in the age group of 7-10 years divided into 2 groups: N 2 O-O 2 sedation and oxygen. Pain perception for local anesthesia was assessed using face, legs, activity, cry, consolability scale. Children′s behavior was assessed using Frankl ratings, depth of sedation using Observer′s Assessment of Alertness/Sedation scale. The vital signs and oxygen saturation were recorded. Results: There was a significantly lower pain reaction to local anesthetic administration in the N 2 O-O 2 group (P < 0.01. Improvement in the behavior of the children belonging to N 2 O-O 2 group during and after the procedure as compared to the O 2 group (P < 0.01 was also observed. All the vital signs recorded were in the normal physiologic limits in both the groups. Conclusion: Pain experienced by children receiving N 2 O-O 2 sedation was significantly lower. N 2 O-O 2 inhalation sedation produces adequate sedation with vital signs within normal limits and treatments successfully completed.

Fully Premixed Low Emission, High Pressure Multi-Fuel Burner

Science.gov (United States)

Nguyen, Quang-Viet (Inventor)

2012-01-01

A low-emissions high-pressure multi-fuel burner includes a fuel inlet, for receiving a fuel, an oxidizer inlet, for receiving an oxidizer gas, an injector plate, having a plurality of nozzles that are aligned with premix face of the injector plate, the plurality of nozzles in communication with the fuel and oxidizer inlets and each nozzle providing flow for one of the fuel and the oxidizer gas and an impingement-cooled face, parallel to the premix face of the injector plate and forming a micro-premix chamber between the impingement-cooled face and the in injector face. The fuel and the oxidizer gas are mixed in the micro-premix chamber through impingement-enhanced mixing of flows of the fuel and the oxidizer gas. The burner can be used for low-emissions fuel-lean fully-premixed, or fuel-rich fully-premixed hydrogen-air combustion, or for combustion with other gases such as methane or other hydrocarbons, or even liquid fuels.

Changes to the bispectral index and regional cerebral blood flow in a sedative state, caused by midazolam administration

International Nuclear Information System (INIS)

Ikeda, Junko

2006-01-01

Psychosedation, as used in the field of dentistry, is intended to provide trouble-free dental care while maintaining a proper level of sedation. One drug used in psychosedation is midazolam, which is known to have a strong amnestic effect. In the current research, I sought to clarify whether the bispectral index (BIS) using electroencephalogram (EEG) analysis can be used for assessment of optimal sedation in psychosedation, and what effects midazolam has on the cerebrum's mechanism of memory. The subjects were 17 healthy adult volunteers. Intravenous sedation involved a single administration of 0.06 mg/kg midazolam, or 6 mg/kg/h propofol, administered for 5 minutes and then continuously administered for 25 minutes at 3 mg/kg/h. For nitrous oxide inhalation sedation, 10-30% nitrous oxide was used. Clinical sedation and the BIS were measured in a variety of circumstances. To examine the effects of midazolam on the central nervous system, changes in brain oxygen consumption in visual memory tasks were assessed through observing changes in areas of brain activation using 3T fMRI. With intravenous sedation using midazolam or propofol, the BIS decreased immediately after drug administration, and the BIS at which optimal sedation was clinically determined was about 65. In contrast, no decrease in the BIS was noted with nitrous oxide inhalation sedation. In observing areas of brain activation by fMRI, the oxygen consumption mainly of visual cortices in the occipital lobe increased as a result of stimulation by visual memory tasks. Regardless of the amnestic effect midazolam produced in subjects, it did not suppress activation of the visual cortices in the occipital lobe. In intravenous sedation using midazolam or propofol, the BIS is effective in determining optimal sedation, and appropriate perioperative management can be performed using the BIS. However, in nitrous oxide inhalation sedation it appears that the BIS cannot be used to monitor levels of sedation. Amnestic

Palliative Sedation: Reliability and Validity of Sedation Scales

NARCIS (Netherlands)

Arevalo Romero, J.; Brinkkemper, T.; van der Heide, A.; Rietjens, J.A.; Ribbe, M.W.; Deliens, L.; Loer, S.A.; Zuurmond, W.W.A.; Perez, R.S.G.M.

2012-01-01

Context: Observer-based sedation scales have been used to provide a measurable estimate of the comfort of nonalert patients in palliative sedation. However, their usefulness and appropriateness in this setting has not been demonstrated. Objectives: To study the reliability and validity of

Visual cortex reactivity in sedated children examined with perfusion MRI (FAIR)

DEFF Research Database (Denmark)

Born, A.P.; Rostrup, Egill; Miranda Gimenez-Ricco, Maria Jo

2002-01-01

Sleeping and sedated children can respond to visual stimulation with a decrease in blood oxygenation level dependent (BOLD) functional MRI signal response. The contribution of metabolic and hemodynamic parameters to this inverse signal response is incompletely understood. It has been hypothesized...... that it is caused by a relatively greater increase of oxygen consumption compared to rCBF (regional cerebral blood flow) increase. We studied the rCBF changes during visual stimulation in four sedated children, aged 4-71 months, and four alert adults, with an arterial water spin labeling technique (FAIR) and BOLD f.......99-2.93), respectively. Thus, in the children, an rCBF increase could not be detected by perfusion MRI, but indications of a FAIR signal decrease were found. An rCBF decrease in the primary visual cortex during stimulation has not been reported previously, but it is a possible explanation for the negative BOLD response...

Colorimetric determination of selenium in mineral premixes .

Science.gov (United States)

Hurlbut, J A; Burkepile, R G; Geisler, C A; Kijak, P J; Rummel, N G

1997-01-01

A method is described for determination of sodium selenite or sodium selenate in mineral-based premixes. It is based on the formation of intense-yellow piazselenol by Se(IV) and 3,3'-diaminobenzidine. Mineral premixes typically contain calcium carbonate as a base material and magnesium carbonate, silicon dioxide, and iron(III) oxide as minor components or additives. In this method, the premix is digested briefly in nitric acid, diluted with water, and filtered to remove any Iron(III) oxide. Ethylenediaminetetraacetic acid and HCl are added to the filtrate, which is heated to near boiling for 1 h to convert any selenate to selenite. After heating, the solution is buffered between pH 2 and 3 with NaOH and formic acid and treated with NH2OH and EDTA; any Se present forms a complex with 3,3'-diaminobenzidine at 60 degrees C. The solution is made basic with NH4OH, and the piazselenol is extracted into toluene. The absorbance of the complex in dried toluene is measured at 420 nm. The method was validated independently by 2 laboratories. Samples analyzed included calcium carbonate fortified with 100, 200, and 300 micrograms Se in the form of sodium selenite or sodium selenate, a calcium carbonate premix containing sodium selenite, a calcium carbonate premix containing sodium selenate, and a commercial premix; 5 replicates of each sample type were analyzed by each laboratory. Average recoveries ranged from 89 to 109% with coefficients of variation from 1.2 to 13.6%.

[Clinical trail on the effect of nitrous oxide/oxygen inhalation sedation on the treatment of acute pulpitis].

Science.gov (United States)

Zhou, Xin-wen; Wang, Li-xin; Liu, Xi-yun

2013-12-01

To evaluate the effectiveness and safety of nitrous oxide/oxygen inhalation sedation in the treatment of acute pulpitis. The study population comprised 72 patients of acute pulpitis treated from September 2012 to March 2013. They were randomly divided into 2 groups, which included experimental group (37 cases) and control group (35 cases). Venham clinical anxiety, cooperative behavior level and WHO clinical pain level evaluation were conducted for the patients. Wilcoxon and Chi-square test were used respectively for statistical analysis with SPSS 14.0 software package. In the experimental group, 86.5% cases behaved comfortable, while in the control group the rate was only 42.9%. 94.6% of the patients in the experimental group felt painless after therapy. The proportion of that in the control group was 68.6%. There was significant difference between the 2 groups (Ppulpitis, while the long-term clinical result still needs further investigation.

Simulation of lean premixed turbulent combustion

International Nuclear Information System (INIS)

Bell, J; Day, M; Almgren, A; Lijewski, M; Rendleman, C; Cheng, R; Shepherd, I

2006-01-01

There is considerable technological interest in developing new fuel-flexible combustion systems that can burn fuels such as hydrogen or syngas. Lean premixed systems have the potential to burn these types of fuels with high efficiency and low NOx emissions due to reduced burnt gas temperatures. Although traditional Scientific approaches based on theory and laboratory experiment have played essential roles in developing our current understanding of premixed combustion, they are unable to meet the challenges of designing fuel-flexible lean premixed combustion devices. Computation, with its ability to deal with complexity and its unlimited access to data, has the potential for addressing these challenges. Realizing this potential requires the ability to perform high fidelity simulations of turbulent lean premixed flames under realistic conditions. In this paper, we examine the specialized mathematical structure of these combustion problems and discuss simulation approaches that exploit this structure. Using these ideas we can dramatically reduce computational cost, making it possible to perform high-fidelity simulations of realistic flames. We illustrate this methodology by considering ultra-lean hydrogen flames and discuss how this type of simulation is changing the way researchers study combustion

Conscious sedation for endoscopic and non-endoscopic interventional gastrointestinal procedures: meeting patients' expectations, missing the standard

International Nuclear Information System (INIS)

Marriott, P.; Laasch, H.-U.; Wilbraham, L.; Marriott, A.; England, R.E.; Martin, D.F.

2004-01-01

AIM: To assess the level of sedation, patient satisfaction and frequency of unplanned events with conscious sedation for interventional procedures. MATERIALS AND METHODS: One hundred and seventeen patients were assessed prospectively before, during and after procedures. Blood pressure, pulse, oxygen saturation and sedation level were monitored and patients followed up after 24 h. Sedation was scored after drugs were given in accordance with an established protocol. Doses were recorded, as were patients' weight, age and ASA grade and any unplanned events and their management. RESULTS: Seventy-six of the 117 patients (65%) had no unplanned event, 20 (17.1%) became agitated, 15 (12.8%) hypotensive, three (2.6%) hypoxic and three (2.6%) had more than one response. Twelve patients required active management. Fifty-two (44.4%) had a sedation level of ≤3 (responsive to verbal commands), but 39 (33.3%) reached level 6. Median doses were midazolam 6 mg (1-20 mg) and pethidine 50 mg (12.5-100 mg). Ninety-three percent were satisfied with their sedation. No adverse effects were observed after 24 h. CONCLUSION: Despite using a sedation protocol, unplanned events occurred in 35% (95% CI=27-44%) of patients, although not all required active management. The sedation levels reached in some exceeded guidelines. Unplanned events were commoner with increased sedation level. Patient satisfaction was high and no permanent damage was observed

Experience with the Large Eddy Simulation (LES) Technique for the Modelling of Premixed and Non-premixed Combustion

OpenAIRE

Malalasekera, W; Ibrahim, SS; Masri, AR; Gubba, SR; Sadasivuni, SK

2013-01-01

Compared to RANS based combustion modelling, the Large Eddy Simulation (LES) technique has recently emerged as a more accurate and very adaptable technique in terms of handling complex turbulent interactions in combustion modelling problems. In this paper application of LES based combustion modelling technique and the validation of models in non-premixed and premixed situations are considered. Two well defined experimental configurations where high quality data are available for validation is...

No-sedation during mechanical ventilation

DEFF Research Database (Denmark)

Laerkner, Eva; Stroem, Thomas; Toft, Palle

2016-01-01

BACKGROUND: Evidence is growing that less or no-sedation is possible and beneficial for patients during mechanical ventilation. AIM: To investigate if there was a difference in patient consciousness and nursing workload comparing a group of patients receiving no-sedation with a group of sedated...... patients with daily wake up, and also to estimate economic consequences of a no-sedation strategy. DESIGN AND METHODS: Data were collected during a prospective trial of 140 mechanically ventilated patients randomized to either no-sedation or to sedation with daily wake up. From day 1 to 7 in the intensive...

Efficacy of two types of palliative sedation therapy defined using intervention protocols: proportional vs. deep sedation.

Science.gov (United States)

Imai, Kengo; Morita, Tatsuya; Yokomichi, Naosuke; Mori, Masanori; Naito, Akemi Shirado; Tsukuura, Hiroaki; Yamauchi, Toshihiro; Kawaguchi, Takashi; Fukuta, Kaori; Inoue, Satoshi

2018-06-01

This study investigated the effect of two types of palliative sedation defined using intervention protocols: proportional and deep sedation. We retrospectively analyzed prospectively recorded data of consecutive cancer patients who received the continuous infusion of midazolam in a palliative care unit. Attending physicians chose the sedation protocol based on each patient's wish, symptom severity, prognosis, and refractoriness of suffering. The primary endpoint was a treatment goal achievement at 4 h: in proportional sedation, the achievement of symptom relief (Support Team Assessment Schedule (STAS) ≤ 1) and absence of agitation (modified Richmond Agitation-Sedation Scale (RASS) ≤ 0) and in deep sedation, the achievement of deep sedation (RASS ≤ - 4). Secondary endpoints included mean scores of STAS and RASS, deep sedation as a result, and adverse events. Among 398 patients who died during the period, 32 received proportional and 18 received deep sedation. The treatment goal achievement rate was 68.8% (22/32, 95% confidence interval 52.7-84.9) in the proportional sedation group vs. 83.3% (15/18, 66.1-100) in the deep sedation group. STAS decreased from 3.8 to 0.8 with proportional sedation at 4 h vs. 3.7 to 0.3 with deep sedation; RASS decreased from + 1.2 to - 1.7 vs. + 1.4 to - 3.7, respectively. Deep sedation was needed as a result in 31.3% (10/32) of the proportional sedation group. No fatal events that were considered as probably or definitely related to the intervention occurred. The two types of intervention protocol well reflected the treatment intention and expected outcomes. Further, large-scale cohort studies are promising.

Balanced Propofol Sedation in Patients Undergoing EUS-FNA: A Pilot Study to Assess Feasibility and Safety

Directory of Open Access Journals (Sweden)

N. Pagano

2011-01-01

Full Text Available Introduction and aims. Balanced propofol sedation (BPS administered by gastroenterologists has gained popularity in endoscopic procedures. Few studies exist about the safety of this approach during endosonography with fine needle aspiration (EUS-FNA. We assessed the safety of BPS in EUS-FNA. Materials and methods. 112 consecutive patients, referred to our unit to perform EUS-FNA, from February 2008 to December 2009, were sedated with BPS. A second gastroenterologist administered the drugs and monitorized the patient. Results. All the 112 patients (62 males, mean age 58.35 completed the examination. The mean dose of midazolam and propofol was, respectively, of 2.1 mg (range 1–4 mg and 350 mg (range 180–400. All patients received oxygen with a mean flux of 4 liter/minute (range 2–6 liters/minute. The mean recovery time after procedure was 25 minutes (range 18–45 minutes. No major complications related to sedation were registered during all procedures. The oxygen saturation of all patients never reduced to less than 85%. Blood systolic pressure during and after the procedure never reduced to less than 100 mmHg. Conclusions. In our experience BPS administered by non-anaesthesiologists provided safe and successful sedation in patients undergoing EUS-FNA.

Safety, cost, and clinical considerations for the use of premixed parenteral nutrition.

Science.gov (United States)

Hall, Jacob W

2015-06-01

Premixed parenteral nutrition (PN) can be used for PN therapy in place of traditional compounded or customized PN. Premixed PN may have a number of advantages over compounded PN such as decreased costs, decreased compounding time, reduced chance for error, and reduced incidence of bloodstream infections. However, premixed PN may not be appropriate for all patients and may have other additional costs associated with its use. This article discusses the data available with regard to the use of premixed PN, focusing on the potential advantages and disadvantages of using premixed PN, and also discusses the implementation of premixed PN in a large tertiary cancer center. © 2015 American Society for Parenteral and Enteral Nutrition.

Effect of sedation with detomidine and butorphanol on pulmonary gas exchange in the horse.

Science.gov (United States)

Nyman, Görel; Marntell, Stina; Edner, Anna; Funkquist, Pia; Morgan, Karin; Hedenstierna, Göran

2009-05-07

Sedation with alpha2-agonists in the horse is reported to be accompanied by impairment of arterial oxygenation. The present study was undertaken to investigate pulmonary gas exchange using the Multiple Inert Gas Elimination Technique (MIGET), during sedation with the alpha2-agonist detomidine alone and in combination with the opioid butorphanol. Seven Standardbred trotter horses aged 3-7 years and weighing 380-520 kg, were studied. The protocol consisted of three consecutive measurements; in the unsedated horse, after intravenous administration of detomidine (0.02 mg/kg) and after subsequent butorphanol administration (0.025 mg/kg). Pulmonary function and haemodynamic effects were investigated. The distribution of ventilation-perfusion ratios (VA/Q) was estimated with MIGET. During detomidine sedation, arterial oxygen tension (PaO2) decreased (12.8 +/- 0.7 to 10.8 +/- 1.2 kPa) and arterial carbon dioxide tension (PaCO2) increased (5.9 +/- 0.3 to 6.1 +/- 0.2 kPa) compared to measurements in the unsedated horse. Mismatch between ventilation and perfusion in the lungs was evident, but no increase in intrapulmonary shunt could be detected. Respiratory rate and minute ventilation did not change. Heart rate and cardiac output decreased, while pulmonary and systemic blood pressure and vascular resistance increased. Addition of butorphanol resulted in a significant decrease in ventilation and increase in PaCO2. Alveolar-arterial oxygen content difference P(A-a)O2 remained impaired after butorphanol administration, the VA/Q distribution improved as the decreased ventilation and persistent low blood flow was well matched. Also after subsequent butorphanol no increase in intrapulmonary shunt was evident. The results of the present study suggest that both pulmonary and cardiovascular factors contribute to the impaired pulmonary gas exchange during detomidine and butorphanol sedation in the horse.

Effect of sedation with detomidine and butorphanol on pulmonary gas exchange in the horse

Directory of Open Access Journals (Sweden)

Morgan Karin

2009-05-01

Full Text Available Abstract Background Sedation with α2-agonists in the horse is reported to be accompanied by impairment of arterial oxygenation. The present study was undertaken to investigate pulmonary gas exchange using the Multiple Inert Gas Elimination Technique (MIGET, during sedation with the α2-agonist detomidine alone and in combination with the opioid butorphanol. Methods Seven Standardbred trotter horses aged 3–7 years and weighing 380–520 kg, were studied. The protocol consisted of three consecutive measurements; in the unsedated horse, after intravenous administration of detomidine (0.02 mg/kg and after subsequent butorphanol administration (0.025 mg/kg. Pulmonary function and haemodynamic effects were investigated. The distribution of ventilation-perfusion ratios (VA/Q was estimated with MIGET. Results During detomidine sedation, arterial oxygen tension (PaO2 decreased (12.8 ± 0.7 to 10.8 ± 1.2 kPa and arterial carbon dioxide tension (PaCO2 increased (5.9 ± 0.3 to 6.1 ± 0.2 kPa compared to measurements in the unsedated horse. Mismatch between ventilation and perfusion in the lungs was evident, but no increase in intrapulmonary shunt could be detected. Respiratory rate and minute ventilation did not change. Heart rate and cardiac output decreased, while pulmonary and systemic blood pressure and vascular resistance increased. Addition of butorphanol resulted in a significant decrease in ventilation and increase in PaCO2. Alveolar-arterial oxygen content difference P(A-aO2 remained impaired after butorphanol administration, the VA/Q distribution improved as the decreased ventilation and persistent low blood flow was well matched. Also after subsequent butorphanol no increase in intrapulmonary shunt was evident. Conclusion The results of the present study suggest that both pulmonary and cardiovascular factors contribute to the impaired pulmonary gas exchange during detomidine and butorphanol sedation in the horse.

Visual cortex reactivity in sedated children examined with perfusion MRI (FAIR)

DEFF Research Database (Denmark)

Born, A P; Rostrup, E; Miranda, M J

2002-01-01

that it is caused by a relatively greater increase of oxygen consumption compared to rCBF (regional cerebral blood flow) increase. We studied the rCBF changes during visual stimulation in four sedated children, aged 4-71 months, and four alert adults, with an arterial water spin labeling technique (FAIR) and BOLD f...

Safety and effectiveness of moderate sedation for radiologic non-vascular intervention

International Nuclear Information System (INIS)

Kim, Tae-Hoon

2006-01-01

The purpose of this study was to prospectively characterize the safety and effectiveness of moderate sedation/analgesia for performing radiologic non-vascular abdominal intervention. During a 3-month period, a total of 63 adult patients with a mean age of 64 years (range:27-82) underwent moderate sedation for 72 radiologic non-vascular interventional procedures. A combination of fentanyl citrate and midazolam hydrochloride, based on the patient's body weight, was intravenously administered until the patient was drowsy and tranquil. The adverse events associated with this moderate sedation were assessed. The visual analog scale format was used to measure the subjective feelings of the patient's pre-pro- cedural anxiety and intraprocedural pain. The mean total dose per kilogram of body weight of fentanyl used in PTBD was 1.148 μg. The mean total dose per kilogram of body weight of midazolam was 0.035 mg in PTBD, PTGBD, AD, PCN, DJS, GS and FRA, 0.039 mg in TDC, and 0.043 mg in BS. A temporary reduction of systolic blood pressure to less than 80 mmHg was observed during 5 procedures (6.9%), whereas a temporary elevation of systolic blood pressure above 150 mmHg was observed during 10 procedures (13.8%). A reduction of arterial oxygen saturation to less than 90% was observed during 14 procedures (19.4%). None of the patients required pharmacologic reversal agents or cardiopulmonary resuscitation. The mean anxiety score recorded before all procedures was 5.2 (distressing). The mean pain score during the procedure, which was recorded after all procedures, was 2.9 (mild). Moderate sedation allows performance of safe and effective radiologic non-vascular intervention, and it is also easy for an interventional radiologist to use. The patients should be continuously monitored to check their vital signs and arterial oxygen saturation during the procedures

Safety and effectiveness of moderate sedation for radiologic non-vascular intervention

Energy Technology Data Exchange (ETDEWEB)

Kim, Tae-Hoon [Dankook University Hospital, Chungju (Korea, Republic of)

2006-06-15

The purpose of this study was to prospectively characterize the safety and effectiveness of moderate sedation/analgesia for performing radiologic non-vascular abdominal intervention. During a 3-month period, a total of 63 adult patients with a mean age of 64 years (range:27-82) underwent moderate sedation for 72 radiologic non-vascular interventional procedures. A combination of fentanyl citrate and midazolam hydrochloride, based on the patient's body weight, was intravenously administered until the patient was drowsy and tranquil. The adverse events associated with this moderate sedation were assessed. The visual analog scale format was used to measure the subjective feelings of the patient's pre-pro- cedural anxiety and intraprocedural pain. The mean total dose per kilogram of body weight of fentanyl used in PTBD was 1.148 {mu}g. The mean total dose per kilogram of body weight of midazolam was 0.035 mg in PTBD, PTGBD, AD, PCN, DJS, GS and FRA, 0.039 mg in TDC, and 0.043 mg in BS. A temporary reduction of systolic blood pressure to less than 80 mmHg was observed during 5 procedures (6.9%), whereas a temporary elevation of systolic blood pressure above 150 mmHg was observed during 10 procedures (13.8%). A reduction of arterial oxygen saturation to less than 90% was observed during 14 procedures (19.4%). None of the patients required pharmacologic reversal agents or cardiopulmonary resuscitation. The mean anxiety score recorded before all procedures was 5.2 (distressing). The mean pain score during the procedure, which was recorded after all procedures, was 2.9 (mild). Moderate sedation allows performance of safe and effective radiologic non-vascular intervention, and it is also easy for an interventional radiologist to use. The patients should be continuously monitored to check their vital signs and arterial oxygen saturation during the procedures.

Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

International Nuclear Information System (INIS)

Karian, V.E.; Burrows, P.E.; Connor, L.; Zurakowski, D.; Mason, K.P.

1999-01-01

Background. Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur. Objective. The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes. Materials and methods. Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression. Results. Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV. Conclusion. The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives. (orig.)

Sedation for pediatric radiological procedures: analysis of potential causes of sedation failure and paradoxical reactions

Energy Technology Data Exchange (ETDEWEB)

Karian, V.E.; Burrows, P.E.; Connor, L. [Dept. of Radiology, Children' s Hospital, Boston, MA (United States); Zurakowski, D. [Dept. of Biostatistics, Children' s Hospital, Boston, MA (United States); Mason, K.P. [Dept. of Anesthesiology, Children' s Hospital, Boston, MA (United States)

1999-11-01

Background. Sedation for diagnostic imaging and interventional radiologic procedures in pediatrics has greatly increased over the past decade. With appropriate patient selection and monitoring, serious adverse effects are infrequent, but failure to sedate and paradoxical reactions do occur. Objective. The purpose of this study was to determine, among patients undergoing sedation for radiologic procedures, the incidence of sedation failure and paradoxical reaction to pentobarbital and to identify potentially correctable causes. Materials and methods. Records of 1665 patients who were sedated in the radiology department from 1 November 1997 to 1 July 1998 were reviewed. Patients failing sedation or experiencing paradoxical reaction were compared with respect to sex, age group, diagnosis, scan type, time of day, NPO status, use of IV contrast and type of sedation agent using the Fisher exact test, Pearson chi-square, analysis of variance (ANOVA), the Student t-test, and logistic regression. Results. Data analysis revealed a sedation failure rate of 1 % and paradoxical reaction rate of 1.2 %. Stepwise multiple logistic regression revealed that the only significant independent multivariate predictor of failure was the need for the administration of a combination of pentobarbital, fentanyl, and midazolam IV. Conclusion. The low rate of sedation failure and paradoxical reactions to pentobarbital was near optimal and probably cannot be improved with the currently available sedatives. (orig.)

A simple one-step chemistry model for partially premixed hydrocarbon combustion

Energy Technology Data Exchange (ETDEWEB)

Fernandez-Tarrazo, Eduardo [Instituto Nacional de Tecnica Aeroespacial, Madrid (Spain); Sanchez, Antonio L. [Area de Mecanica de Fluidos, Universidad Carlos III de Madrid, Leganes 28911 (Spain); Linan, Amable [ETSI Aeronauticos, Pl. Cardenal Cisneros 3, Madrid 28040 (Spain); Williams, Forman A. [Department of Mechanical and Aerospace Engineering, University of California San Diego, La Jolla, CA 92093-0411 (United States)

2006-10-15

This work explores the applicability of one-step irreversible Arrhenius kinetics with unity reaction order to the numerical description of partially premixed hydrocarbon combustion. Computations of planar premixed flames are used in the selection of the three model parameters: the heat of reaction q, the activation temperature T{sub a}, and the preexponential factor B. It is seen that changes in q with equivalence ratio f need to be introduced in fuel-rich combustion to describe the effect of partial fuel oxidation on the amount of heat released, leading to a universal linear variation q(f) for f>1 for all hydrocarbons. The model also employs a variable activation temperature T{sub a}(f) to mimic changes in the underlying chemistry in rich and very lean flames. The resulting chemistry description is able to reproduce propagation velocities of diluted and undiluted flames accurately over the whole flammability limit. Furthermore, computations of methane-air counterflow diffusion flames are used to test the proposed chemistry under nonpremixed conditions. The model not only predicts the critical strain rate at extinction accurately but also gives near-extinction flames with oxygen leakage, thereby overcoming known predictive limitations of one-step Arrhenius kinetics. (author)

Early structure of LPG partially premixed conically stabilized flames

KAUST Repository

Elbaz, Ayman M.

2013-01-01

This paper presents experimental investigation of LPG partially premixed turbulent flames stabilized within a conical nozzle burner under constant degree of partial premixing. The stability limits and mean flame structure are presented based

Conscious sedation for endoscopic and non-endoscopic interventional gastrointestinal procedures: meeting patients' expectations, missing the standard

Energy Technology Data Exchange (ETDEWEB)

Marriott, P.; Laasch, H.-U.; Wilbraham, L.; Marriott, A.; England, R.E.; Martin, D.F. E-mail: derrick.martin@smtr.nhs.uk

2004-02-01

AIM: To assess the level of sedation, patient satisfaction and frequency of unplanned events with conscious sedation for interventional procedures. MATERIALS AND METHODS: One hundred and seventeen patients were assessed prospectively before, during and after procedures. Blood pressure, pulse, oxygen saturation and sedation level were monitored and patients followed up after 24 h. Sedation was scored after drugs were given in accordance with an established protocol. Doses were recorded, as were patients' weight, age and ASA grade and any unplanned events and their management. RESULTS: Seventy-six of the 117 patients (65%) had no unplanned event, 20 (17.1%) became agitated, 15 (12.8%) hypotensive, three (2.6%) hypoxic and three (2.6%) had more than one response. Twelve patients required active management. Fifty-two (44.4%) had a sedation level of {<=}3 (responsive to verbal commands), but 39 (33.3%) reached level 6. Median doses were midazolam 6 mg (1-20 mg) and pethidine 50 mg (12.5-100 mg). Ninety-three percent were satisfied with their sedation. No adverse effects were observed after 24 h. CONCLUSION: Despite using a sedation protocol, unplanned events occurred in 35% (95% CI=27-44%) of patients, although not all required active management. The sedation levels reached in some exceeded guidelines. Unplanned events were commoner with increased sedation level. Patient satisfaction was high and no permanent damage was observed.

Pembakaran Premixed Minyak Nabati Pada Bunsen Burner Type Silinder

OpenAIRE

La Muhaya, Syamsul Bahri; Wardana, ING; Widhiyanuriyawan, Denny

2015-01-01

In the premixed combustion wave propagation combustion occurs is called the flame front. Premixed flame will propagate at the speed of moving towards the reactants unique. If the speed of the reactants is equal to the speed of propagation of fire, the fire (reaction zone) will be stationary. It is necessary to follow up on the influence of equivalence ratio (φ) varied with laminar flame speed (SL) in the premixed combustion of vegetable oil (virgin coconut oil, jatropha and cotton seeds). Res...

The role of sedation tests in identifying sedative drug effects in healthy volunteers and their power to dissociate sedative-related impairments from memory dysfunctions.

Science.gov (United States)

Wezenberg, E; Sabbe, B G C; Hulstijn, W; Ruigt, G S F; Verkes, R J

2007-08-01

The study investigated whether four specified drugs would show similar patterns on tests considered to measure sedation. In addition, their drug-effect patterns on sedation and memory performance were compared to determine whether the sedative effects could be differentiated from the memory effects. Two double-blind, placebo-controlled, crossover studies, each with 16 healthy volunteers, were performed, one testing lorazepam (2.5 mg) and mirtazapine (15 mg) and the other olanzapine (10 mg) and haloperidol (2.5 mg). Subjective sedation was assessed by means of visual analogue scales (VAS) and objective sedation using a simple-reaction-time (SRT) task and a choice-reaction-time (CRT) task, code substitution (symbol digit substitution test (SDST)) and the peak velocity of saccadic eye movements (SEM). A verbal memory test (VMT) was administered to evaluate memory capacity. Apart from haloperidol, all drugs proved to impair performance on all five sedation indices. Contrary to the VAS, the objective measures yielded different response profiles. Two types of drug-effect patterns emerged: one for greater impairments in response speed (SRT, SEM) and one for greater impairments in information processing (CRT, SDST). Lorazepam and olanzapine impeded memory performance, whereas mirtazapine did not. With the use of standardized scores it proved possible to differentiate between the size of the effects of the drugs on the sedation and memory tests. To accurately assess the level and nature of sedation and to differentiate sedation from memory impairments different types of sedation measures are required. Besides studying the subjective effects, it is recommended to also test psychomotor responses and information processing speed.

CSP-based chemical kinetics mechanisms simplification strategy for non-premixed combustion: An application to hybrid rocket propulsion

KAUST Repository

Ciottoli, Pietro P.

2017-08-14

A set of simplified chemical kinetics mechanisms for hybrid rocket applications using gaseous oxygen (GOX) and hydroxyl-terminated polybutadiene (HTPB) is proposed. The starting point is a 561-species, 2538-reactions, detailed chemical kinetics mechanism for hydrocarbon combustion. This mechanism is used for predictions of the oxidation of butadiene, the primary HTPB pyrolysis product. A Computational Singular Perturbation (CSP) based simplification strategy for non-premixed combustion is proposed. The simplification algorithm is fed with the steady-solutions of classical flamelet equations, these being representative of the non-premixed nature of the combustion processes characterizing a hybrid rocket combustion chamber. The adopted flamelet steady-state solutions are obtained employing pure butadiene and gaseous oxygen as fuel and oxidizer boundary conditions, respectively, for a range of imposed values of strain rate and background pressure. Three simplified chemical mechanisms, each comprising less than 20 species, are obtained for three different pressure values, 3, 17, and 36 bar, selected in accordance with an experimental test campaign of lab-scale hybrid rocket static firings. Finally, a comprehensive strategy is shown to provide simplified mechanisms capable of reproducing the main flame features in the whole pressure range considered.

Volatile Components of the Essential Oil of Artemisia montana and Their Sedative Effects.

Science.gov (United States)

Kunihiro, Kento; Myoda, Takao; Tajima, Noriaki; Gotoh, Kotaro; Kaneshima, Tai; Someya, Takao; Toeda, Kazuki; Fujimori, Takane; Nishizawa, Makoto

2017-08-01

The sedative effects of volatile components in the essential oil of Artemisia montana ("Yomogi") were investigated and measured using gas chromatography-mass spectrometry (GC-MS). Major components identified included 1,8-cineol, camphor, borneol, α-piperitone, and caryophyllene oxide. Among them, 1,8-cineol exhibited the highest flavor dilution (FD) value in an aroma extract dilution analysis (AEDA), followed by borneol, o-cymene, β-thujone, and bornyl acetate. The sedative effects of yomogi oil aroma were evaluated by sensory testing, analysis of salivary α-amylase activity, and measurement of relative fluctuation of oxygenated hemoglobin concentration in the brain using near-infrared spectroscopy (NIRS). All results indicated the stress-reducing effects of the essential oil following nasal exposure, and according to the NIRS analysis, 1,8-cineol is likely responsible for the sedative effects of yomogi oil.

Quantification of extinction mechanism in counterflow premixed flames

KAUST Repository

Choi, Sangkyu; Cho, Eunseong; Chung, Suk-Ho

2014-01-01

The extinction mechanisms of stretched premixed flames have been investigated numerically for the fuels of CH4, C3H8, H2, CO and for the mixture fuels of CH4+H2 and CO+H2 by adopting symmetric double premixed flames in a counterflow configuration

Large eddy simulation of premixed and non-premixed combustion in a Stagnation Point Reverse Flow combustor

Science.gov (United States)

Undapalli, Satish

A new combustor referred to as Stagnation Point Reverse Flow (SPRF) combustor has been developed at Georgia Tech to meet the increasingly stringent emission regulations. The combustor incorporates a novel design to meet the conflicting requirements of low pollution and high stability in both premixed and non-premixed modes. The objective of this thesis work is to perform Large Eddy Simulations (LES) on this lab-scale combustor and elucidate the underlying physics that has resulted in its excellent performance. To achieve this, numerical simulations have been performed in both the premixed and non-premixed combustion modes, and velocity field, species field, entrainment characteristics, flame structure, emissions, and mixing characteristics have been analyzed. Simulations have been carried out first for a non-reactive case to resolve relevant fluid mechanics without heat release by the computational grid. The computed mean and RMS quantities in the non-reacting case compared well with the experimental data. Next, the simulations were extended for the premixed reactive case by employing different sub-grid scale combustion chemistry closures: Eddy Break Up (EBU), Artificially Thickened Flame (TF) and Linear Eddy Mixing (LEM) models. Results from the EBU and TF models exhibit reasonable agreement with the experimental velocity field. However, the computed thermal and species fields have noticeable discrepancies. Only LEM with LES (LEMLES), which is an advanced scalar approach, has been able to accurately predict both the velocity and species fields. Scalar mixing plays an important role in combustion, and this is solved directly at the sub-grid scales in LEM. As a result, LEM accurately predicts the scalar fields. Due to the two way coupling between the super-grid and sub-grid quantities, the velocity predictions also compare very well with the experiments. In other approaches, the sub-grid effects have been either modeled using conventional approaches (EBU) or need

Office-based deep sedation for pediatric ophthalmologic procedures using a sedation service model.

Science.gov (United States)

Lalwani, Kirk; Tomlinson, Matthew; Koh, Jeffrey; Wheeler, David

2012-01-01

Aims. (1) To assess the efficacy and safety of pediatric office-based sedation for ophthalmologic procedures using a pediatric sedation service model. (2) To assess the reduction in hospital charges of this model of care delivery compared to the operating room (OR) setting for similar procedures. Background. Sedation is used to facilitate pediatric procedures and to immobilize patients for imaging and examination. We believe that the pediatric sedation service model can be used to facilitate office-based deep sedation for brief ophthalmologic procedures and examinations. Methods. After IRB approval, all children who underwent office-based ophthalmologic procedures at our institution between January 1, 2000 and July 31, 2008 were identified using the sedation service database and the electronic health record. A comparison of hospital charges between similar procedures in the operating room was performed. Results. A total of 855 procedures were reviewed. Procedure completion rate was 100% (C.I. 99.62-100). There were no serious complications or unanticipated admissions. Our analysis showed a significant reduction in hospital charges (average of $1287 per patient) as a result of absent OR and recovery unit charges. Conclusions. Pediatric ophthalmologic minor procedures can be performed using a sedation service model with significant reductions in hospital charges.

Office-Based Deep Sedation for Pediatric Ophthalmologic Procedures Using a Sedation Service Model

Directory of Open Access Journals (Sweden)

Kirk Lalwani

2012-01-01

Full Text Available Aims. (1 To assess the efficacy and safety of pediatric office-based sedation for ophthalmologic procedures using a pediatric sedation service model. (2 To assess the reduction in hospital charges of this model of care delivery compared to the operating room (OR setting for similar procedures. Background. Sedation is used to facilitate pediatric procedures and to immobilize patients for imaging and examination. We believe that the pediatric sedation service model can be used to facilitate office-based deep sedation for brief ophthalmologic procedures and examinations. Methods. After IRB approval, all children who underwent office-based ophthalmologic procedures at our institution between January 1, 2000 and July 31, 2008 were identified using the sedation service database and the electronic health record. A comparison of hospital charges between similar procedures in the operating room was performed. Results. A total of 855 procedures were reviewed. Procedure completion rate was 100% (C.I. 99.62–100. There were no serious complications or unanticipated admissions. Our analysis showed a significant reduction in hospital charges (average of $1287 per patient as a result of absent OR and recovery unit charges. Conclusions. Pediatric ophthalmologic minor procedures can be performed using a sedation service model with significant reductions in hospital charges.

Sedation and monitoring for gastrointestinal endoscopy.

Science.gov (United States)

Amornyotin, Somchai

2013-02-16

The safe sedation of patients for diagnostic or therapeutic procedures requires a combination of properly trained physicians and suitable facilities. Additionally, appropriate selection and preparation of patients, suitable sedative technique, application of drugs, adequate monitoring, and proper recovery of patients is essential. The goal of procedural sedation is the safe and effective control of pain and anxiety as well as to provide an appropriate degree of memory loss or decreased awareness. Sedation practices for gastrointestinal endoscopy (GIE) vary widely. The majority of GIE patients are ambulatory cases. Most of this procedure requires a short time. So, short acting, rapid onset drugs with little adverse effects and improved safety profiles are commonly used. The present review focuses on commonly used regimens and monitoring practices in GIE sedation. This article is to discuss the decision making process used to determine appropriate pre-sedation assessment, monitoring, drug selection, dose of sedative agents, sedation endpoint and post-sedation care. It also reviews the current status of sedation and monitoring for GIE procedures in Thailand.

[General practitioner and palliative sedation].

Science.gov (United States)

Schweitzer, Bart

2014-01-01

Recent publications in Dutch national newspapers on palliative sedation have raised concerns about its use in general practice. There is now evidence that there is no significant increase in the incidence of palliative sedation. Euthanasia requests were pending in 20.8% of the cases in which palliative sedation was performed, but the general practitioners could clearly justify why they made this choice. This is important because it indicates that they are aware of a sharp distinction between euthanasia and palliative sedation. Although the decision to perform palliative sedation was discussed with almost all cancer patients, patient involvement was less present in non-cancer conditions. This may be related to different disease trajectories, but it also indicates that attention should be devoted to earlier identification of patients in need of palliative care. The findings confirm that the practice of palliative sedation by general practitioners largely reflects the recommendations of the Dutch National Guideline on Palliative Sedation.

Palliative sedation in nursing anesthesia.

Science.gov (United States)

Wolf, Michael T

2013-04-01

Palliative sedation is a technique of providing a sedative for end-of-life care to patients with intractable pain. The literature discusses the techniques and use of palliative sedation. Numerous articles have been written regarding the issues surrounding its use, but no literature has discussed the prescription or administration of palliative sedation by a nurse anesthetist. By understanding the concept and ethics involved in its use and providing nursing care that is theory based, the author argues that the involvement of nursing anesthesia is appropriate and within the scope of practice. Few other healthcare disciplines can provide the patient care and empirical knowledge that is imperative in the care of the dying patient. This article discusses the concept and ethics of palliative sedation and presents a case of providing palliative sedation to a terminally ill patient by an experienced nurse anesthetist. Palliative sedation should be understood, embraced, and utilized as an area of expertise suited for nursing anesthesia.

Variation in diurnal sedation in mechanically ventilated patients who are managed with a sedation protocol alone or a sedation protocol and daily interruption.

Science.gov (United States)

Mehta, Sangeeta; Meade, Maureen; Burry, Lisa; Mallick, Ranjeeta; Katsios, Christina; Fergusson, Dean; Dodek, Peter; Burns, Karen; Herridge, Margaret; Devlin, John W; Tanios, Maged; Fowler, Robert; Jacka, Michael; Skrobik, Yoanna; Olafson, Kendiss; Cook, Deborah

2016-08-01

Mechanically ventilated patients may receive more sedation during the night than during the day, potentially delaying extubation. We compared nighttime and daytime benzodiazepine and opioid administration in adult patients enrolled in a multicenter sedation trial comparing protocolized sedation alone or protocolized sedation combined with daily sedation interruption; and we evaluated whether nighttime and daytime doses were associated with liberation from mechanical ventilation. This is a secondary analysis of a randomized trial which was conducted in 16 North American medical-surgical ICUs. In all 423 patients, nurses applied a validated sedation scale hourly to titrate benzodiazepine and opioid infusions to achieve a light level of sedation. Using fentanyl equivalents and midazolam equivalents, we compared dosages administered during night (19:00 to 07:00) and day (07:00 to 19:00) shifts. Using multivariable logistic regression we evaluated the association between nighttime and daytime opioid and sedative doses, and spontaneous breathing trial (SBT) conduct, SBT success, and extubation. Nighttime benzodiazepine and opioid doses were significantly higher than daytime doses (mean difference midazolam equivalents 23.3 mg, 95 % CI 12.9, 33.8, p Patients were more often restrained during day shifts (76.3 % vs 73.7 %, p patient despite successful SBT. Patients received higher doses of opioids and benzodiazepines at night. Higher nighttime doses were associated with SBT failure and delayed extubation. ClinicalTrials.gov NCT00675363 . Registered 7 May 2008.

Study on the Enhancement Effect of Dielectric Barrier Discharge on the Premixed Methane/Oxygen/Helium Flame Velocity

International Nuclear Information System (INIS)

Mu Haibao; Yu Lin; Li Ping; Zhang Guanjun; Tang Chenglong; Wang Jinhua

2015-01-01

Recently, plasma-assisted combustion has become a potentially applicable technology in many combustion scenarios. In this paper, a dielectric barrier discharge (DBD) plasma generator is designed to explore the effect of plasma on the CH4 oxidation process, and several properties of combustion are considered. First, in the presence or absence of plasma discharge, physical appearance of the flame is examined and analyzed. Second, the flame propagation velocity is calculated by the flame front extracted from the imaging data with the Bunsen burner method. Finally, the main molecular components and their intensity variation in the flame and the plasma zones are identified with an emission spectrograph to analyze the effect of active species on the combustion process. We also discuss the possible kinetic regime of plasma-assisted combustion. Experimental results imply that plasma discharge applied to the premixed CH4/O2/He mixture significantly raises the flame speed with equivalence ratios ranging from 0.85 to 1.10, with the flame speed improved by 17% to 35%. It can be seen that plasma can improve methane oxidation efficiency in the premixed fuel/oxidizer, especially at a low equivalence ratio. (paper)

The role of sedation tests in identifying sedative drug effects in healthy volunteers and their power to dissociate sedative-related impairments from memory dysfunctions

NARCIS (Netherlands)

Wezenberg, E.; Sabbe, B.G.C.; Hulstijn, W.; Ruigt, G.S.F.; Verkes, R.J.

2007-01-01

The study investigated whether four specified drugs would show similar patterns on tests considered to measure sedation. In addition, their drug-effect patterns on sedation and memory performance were compared to determine whether the sedative effects could be differentiated from the memory effects.

The role of sedation tests in identifying sedative drug effects in healthy volunteers and their power to dissociate sedative-related impairments from memory dysfunctions.

NARCIS (Netherlands)

Wezenberg, E.; Sabbe, B.G.C.; Hulstijn, W.; Ruigt, G.S.F.; Verkes, R.J.

2007-01-01

The study investigated whether four specified drugs would show similar patterns on tests considered to measure sedation. In addition, their drug-effect patterns on sedation and memory performance were compared to determine whether the sedative effects could be differentiated from the memory

Thermal Radiation Properties of Turbulent Lean Premixed Methane Air Flames

National Research Council Canada - National Science Library

Ji, Jun; Sivathanu, Y. R; Gore, J. P

2000-01-01

... of turbulent premixed flames. Reduced cooling airflows in lean premixed combustors, miniaturization of combustors, and the possible use of radiation sensors in combustion control schemes are some of the practical reasons...

Three-dimensional simulations of cellular non-premixed jet flames

Energy Technology Data Exchange (ETDEWEB)

Valaer, A.L.; Frouzakis, C.E.; Boulouchos, K. [Aerothermochemistry and Combustion System Laboratory, Swiss Federal Institute of Technology, CH-8092 Zurich (Switzerland); Papas, P. [Division of Engineering, Colorado School of Mines, Golden, CO 80401 (United States); Tomboulides, A.G. [Department of Engineering and Management of Energy Resources, University of Western Macedonia, 50100 Kozani (Greece)

2010-04-15

The formation, dynamics and structure of cellular flames in circular non-premixed jets are examined with three-dimensional numerical simulations incorporating detailed descriptions of chemistry and transport. Similar to past experiments reported in the literature, CO{sub 2}-diluted hydrogen in diluted or pure oxygen co-flowing streams in the proximity of the extinction limit are considered. As in the experiments, several preferred cellular states are found to co-exist with the particular state realized depending on initial conditions as well as on the jet characteristics. The simulations provide additionally the temporal transitions to different stationary or rotating cellular flames, their detailed structure, and the dependence of the scaling of the realized number of cells with the vorticity thickness. (author)

Soot Formation in Freely-Propagating Laminar Premixed Flames

Science.gov (United States)

Lin, K.-C.; Hassan, M. I.; Faeth, G. M.

1997-01-01

Soot formation within hydrocarbon-fueled flames is an important unresolved problem of combustion science. Thus, the present study is considering soot formation in freely-propagating laminar premixed flames, exploiting the microgravity environment to simplify measurements at the high-pressure conditions of interest for many practical applications. The findings of the investigation are relevant to reducing emissions of soot and continuum radiation from combustion processes, to improving terrestrial and spacecraft fire safety, and to developing methods of computational combustion, among others. Laminar premixed flames are attractive for studying soot formation because they are simple one-dimensional flows that are computationally tractable for detailed numerical simulations. Nevertheless, studying soot-containing burner-stabilized laminar premixed flames is problematical: spatial resolution and residence times are limited at the pressures of interest for practical applications, flame structure is sensitive to minor burner construction details so that experimental reproducibility is not very good, consistent burner behavior over the lengthy test programs needed to measure soot formation properties is hard to achieve, and burners have poor durability. Fortunately, many of these problems are mitigated for soot-containing, freely-propagating laminar premixed flames. The present investigation seeks to extend work in this laboratory for various soot processes in flames by observing soot formation in freely-propagating laminar premixed flames. Measurements are being made at both Normal Gravity (NG) and MicroGravity (MG), using a short-drop free-fall facility to provide MG conditions.

Palliative sedation for intolerable suffering.

Science.gov (United States)

Maltoni, Marco; Scarpi, Emanuela; Nanni, Oriana

2014-07-01

The purpose of this review is to provide an update on palliative sedation in palliative and end-of-life care. Palliative sedation is the medical procedure used to deal with refractory symptoms in advanced cancer patients when all other specific approaches have failed. Palliative sedation, in the strictest sense of the term, is a proportionate (proportionate palliative sedation, PPS) and intrinsically variable procedure used on an individual basis to relieve refractory symptoms in terminally ill patients, without the intention of hastening death. Completely separate from any other end-of-life decision and not intended to hasten death, palliative sedation has been shown not to have a detrimental impact on survival. To maintain palliative sedation as a legitimate clinical procedure from any ethical or clinical point of view, it must be limited to the restricted area for which it was conceived, that is, relief from refractory suffering as deemed necessary by a patient and by an experienced palliative care team. In this way, there is no risk of associating palliative sedation with other end-of-life decisions. Close collaboration is needed between oncologists and palliative care physicians for this clinical procedure.

Rectal Thiopental versus Intramuscular Ketamine in Pediatric Procedural Sedation and Analgesia; a Randomized Clinical Trial

Directory of Open Access Journals (Sweden)

Reza Azizkhani

2015-01-01

Full Text Available Introduction: Physicians frequently deal with procedures which require sedation of pediatric patients. Laceration repair is one of them. No study has been performed regarding the comparison between induction of sedation with sodium thiopental and ketamine in laceration repair. Therefore, the present study was aimed to comparison of induced sedation by rectal sodium thiopental and muscular injection of hydrochloride ketamine in pediatric patients need laceration repair. Methods: The presented study is a single-blinded clinical trial performed through 2013 to 2014 in Ayatollah Kashani and Alzahra Hospitals, Isfahan, Iran. Patients from 3 months to 14 years, needed sedation for laceration repair, were entered. Patients were sequentially evaluated and randomly categorized in two groups of hydrochloride ketamine with dose of 2-4 milligram per kilogram and sodium thiopental with dose of 25 milligram per kilogram. Demographic data and vital signs before drug administration and after induction of sedation, Ramsey score, time to onset of action, and sedation recovery time were evaluated. Chi-squared, Mann-Whitney, and Non-parametric analysis of covariance tests were used. P<0.05 was considered as a significant level. Results: In this study 60 pediatric patients were entered. 30 patients with mean age of 42.8±18.82 months were received sodium thiopental and the rest with mean age of 30.08±16.88 months given ketamine. Mann-Whitney test was showed that time to onset of action in sodium thiopental group (28.23±5.18 minutes was significantly higher than ketamine (7.77±4.13 minutes, (p<0.001. The sedation recovery time in ketamine group (29.83±7.70 was higher than sodium thiopental. Depth of sedation had no significant difference between two groups based on Ramsey score (p=0.87. No significant difference was seen between two groups in the respiratory rate (df=1, 58; F=0.002; P=0.96 and heart rate (df=1, 58; F=0.98; P=0.33. However, arterial oxygen

Palliative sedation, not slow euthanasia: a prospective, longitudinal study of sedation in Flemish palliative care units.

Science.gov (United States)

Claessens, Patricia; Menten, Johan; Schotsmans, Paul; Broeckaert, Bert

2011-01-01

Palliative sedation remains a much debated and controversial issue. The limited literature on the topic often fails to answer ethical questions concerning this practice. The aim of this study was to describe the characteristics of patients who are being sedated for refractory symptoms in palliative care units (PCUs) from the time of admission until the day of death. A prospective, longitudinal, descriptive design was used to assess data in eight PCUs. The total sample consisted of 266 patients. Information on demographics, medication, food and fluid intake, decision making, level of consciousness, and symptom experience were gathered by nurses and researchers three times a week. If patients received palliative sedation, extra information was gathered. Of all included patients (n=266), 7.5% received palliative sedation. Sedation started, on average, 2.5 days before death and for half of these patients, the form of sedation changed over time. At the start of sedation, patients were in the end stage of their illness and needed total care. Patients were fully conscious and had very limited oral food or fluid intake. Only three patients received artificial fluids at the start of sedation. Patients reported, on average, two refractory symptoms, the most important ones being pain, fatigue, depression, drowsiness, and loss of feeling of well-being. In all cases, the patient gave consent to start palliative sedation because of increased suffering. This study revealed that palliative sedation is only administered in exceptional cases where refractory suffering is evident and for those patients who are close to the ends of their lives. Moreover, this study supports the argument that palliative sedation has no life-shortening effect. Copyright © 2011 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Sedation-related complications in gastrointestinal endoscopy.

Science.gov (United States)

Amornyotin, Somchai

2013-11-16

Sedation practices for gastrointestinal endoscopic (GIE) procedures vary widely in different countries depending on health system regulations and local circumstances. The goal of procedural sedation is the safe and effective control of pain and anxiety, as well as to provide an appropriate degree of memory loss or decreased awareness. Sedation-related complications in gastrointestinal endoscopy, once occurred, can lead to significant morbidity and occasional mortality in patients. The risk factors of these complications include the type, dose and mode of administration of sedative agents, as well as the patient's age and underlying medical diseases. Complications attributed to moderate and deep sedation levels are more often associated with cardiovascular and respiratory systems. However, sedation-related complications during GIE procedures are commonly transient and of a mild degree. The risk for these complications while providing any level of sedation is greatest when caring for patients already medically compromised. Significant unwanted complications can generally be prevented by careful pre-procedure assessment and preparation, appropriate monitoring and support, as well as post-procedure management. Additionally, physicians must be prepared to manage these complications. This article will review sedation-related complications during moderate and deep sedation for GIE procedures and also address their appropriate management.

Premixed direct injection nozzle

Science.gov (United States)

Zuo, Baifang [Simpsonville, SC; Johnson, Thomas Edward [Greer, SC; Lacy, Benjamin Paul [Greer, SC; Ziminsky, Willy Steve [Simpsonville, SC

2011-02-15

An injection nozzle having a main body portion with an outer peripheral wall is disclosed. The nozzle includes a plurality of fuel/air mixing tubes disposed within the main body portion and a fuel flow passage fluidly connected to the plurality of fuel/air mixing tubes. Fuel and air are partially premixed inside the plurality of the tubes. A second body portion, having an outer peripheral wall extending between a first end and an opposite second end, is connected to the main body portion. The partially premixed fuel and air mixture from the first body portion gets further mixed inside the second body portion. The second body portion converges from the first end toward said second end. The second body portion also includes cooling passages that extend along all the walls around the second body to provide thermal damage resistance for occasional flame flash back into the second body.

Staff education, regular sedation and analgesia quality feedback, and a sedation monitoring technology for improving sedation and analgesia quality for critically ill, mechanically ventilated patients: a cluster randomised trial.

Science.gov (United States)

Walsh, Timothy S; Kydonaki, Kalliopi; Antonelli, Jean; Stephen, Jacqueline; Lee, Robert J; Everingham, Kirsty; Hanley, Janet; Phillips, Emma C; Uutela, Kimmo; Peltola, Petra; Cole, Stephen; Quasim, Tara; Ruddy, James; McDougall, Marcia; Davidson, Alan; Rutherford, John; Richards, Jonathan; Weir, Christopher J

2016-10-01

Optimal sedation of patients in intensive care units (ICUs) requires the avoidance of pain, agitation, and unnecessary deep sedation, but these outcomes are challenging to achieve. Excessive sedation can prolong ICU stay, whereas light sedation can increase pain and frightening memories, which are commonly recalled by ICU survivors. We aimed to assess the effectiveness of three interventions to improve sedation and analgesia quality: an online education programme; regular feedback of sedation-analgesia quality data; and use of a novel sedation-monitoring technology (the Responsiveness Index [RI]). We did a cluster randomised trial in eight ICUs, which were randomly allocated to receive education alone (two ICUs), education plus sedation-analgesia quality feedback (two ICUs), education plus RI monitoring technology (two ICUs), or all three interventions (two ICUs). Randomisation was done with computer-generated random permuted blocks, stratified according to recruitment start date. A 45 week baseline period was followed by a 45 week intervention period, separated by an 8 week implementation period in which the interventions were introduced. ICU and research staff were not masked to study group assignment during the intervention period. All mechanically ventilated patients were potentially eligible. We assessed patients' sedation-analgesia quality for each 12 h period of nursing care, and sedation-related adverse events daily. Our primary outcome was the proportion of care periods with optimal sedation-analgesia, defined as being free from excessive sedation, agitation, poor limb relaxation, and poor ventilator synchronisation. Analysis used multilevel generalised linear mixed modelling to explore intervention effects in a single model taking clustering and patient-level factors into account. A concurrent mixed-methods process evaluation was undertaken to help understand the trial findings. The trial is registered with ClinicalTrials.gov, number NCT01634451. Between

Sedation for pediatric diagnostic imaging: use of pediatric and nursing resources as an alternative to a radiology department sedation team

International Nuclear Information System (INIS)

Ruess, Lynne; O'Connor, Stephen C.; Mikita, Cecilia P.; Creamer, Kevin M.

2002-01-01

Objective. To develop a pathway to provide safe, effective, and efficient sedation for pediatric diagnostic imaging studies using non-radiology personnel. Materials and methods. A multidisciplinary team considered manpower and training requirements and national sedation standards before designing a sedation pathway, which included scheduling, pre-sedation history and physical, medication protocols, and monitoring. Oral and IV medication protocols were developed based on patient age and weight. Sedation delays were defined as >15 min (IV) or >30 min (PO) from start of sedation to start of imaging. A sedation failure resulted in an incomplete diagnostic imaging study. Failure rates of 124 sedations before and 388 sedations after the pathway were compared.Results. The sedation failure rate for 7 months prior to pathway initiation was 15% (19/124). In the first 25 months after pathway initiation, failures were significantly reduced to 1.5% (6/388) (P 55 min). Deviation from the recommended medication protocol accounted for most of the 115 delays. Only minor adverse events were seen (12/388, 3.1%).Conclusion. Implementing a pediatric sedation pathway significantly decreases the sedation failure rate. Pediatric residents and nurses can safely, effectively and efficiently sedate pediatric patients for routine diagnostic imaging procedures without the need for a radiology department sedation team in a department with a small-to-moderate volume of pediatric patients. (orig.)

The indicator of sedation need (IOSN).

Science.gov (United States)

Coulthard, Paul

2013-01-01

Conscious sedation in dentistry is usually indicated because a patient's anxiety can prohibit the necessary dental treatment being undertaken. It may also be indicated because of unpleasant or lengthy treatment or to prevent exacerbation of a patient's medical or behavioural condition by anxiety. The indicator of sedation need (IOSN) tool has been developed to help support dentists in their clinical decision-making and uses information about a patient's anxiety, medical and behavioural status and treatment complexity. The IOSN has been used to measure sedation need and has shown that 5.1% of patients attending general dental practices have a high need of conscious sedation. IOSN has also been used to investigate the need for conscious sedation in the general population among dental practice attenders and those who don't attend. The proportion was found to be 6.7%. Some patients require conscious sedation in order to access dental care. The indicator of sedation need (IOSN) tool helps in the decision-making process.

Palliative Sedation in Patients With Cancer.

Science.gov (United States)

Maltoni, Marco; Setola, Elisabetta

2015-10-01

Palliative sedation involves the use of sedative medication to relieve refractory symptoms in patients by reducing their level of consciousness. Although it is considered an acceptable clinical practice from most ethical points of view, palliative sedation is still a widely debated procedure and merits better understanding. The relevant medical literature pertaining to palliative sedation was analyzed and reviewed from various technical, relational, and bioethical perspectives. Proportionate palliative sedation is considered to be the most clinically appropriate modality for performing palliative sedation. However, guidelines must be followed to ensure that it is performed correctly. Benzodiazepines represent the first therapeutic option and careful monitoring of dosages is essential to avoid oversedation or undersedation. Proportionate palliative sedation is used to manage and relieve refractory symptoms in patients with cancer during their last days or hours of life. Evidence suggests that its use has no detrimental effect on survival. A different decision-making process is used to manage the withdrawal of hydration than the process used to determine whether proportionate palliative sedation is appropriate. Communication between patients, their relatives, and the health care staff is important during this medical intervention.

Pediatric dental sedation: challenges and opportunities.

Science.gov (United States)

Nelson, Travis M; Xu, Zheng

2015-01-01

High levels of dental caries, challenging child behavior, and parent expectations support a need for sedation in pediatric dentistry. This paper reviews modern developments in pediatric sedation with a focus on implementing techniques to enhance success and patient safety. In recent years, sedation for dental procedures has been implicated in a disproportionate number of cases that resulted in death or permanent neurologic damage. The youngest children and those with more complicated medical backgrounds appear to be at greatest risk. To reduce complications, practitioners and regulatory bodies have supported a renewed focus on health care quality and safety. Implementation of high fidelity simulation training and improvements in patient monitoring, including end-tidal carbon dioxide, are becoming recognized as a new standard for sedated patients in dental offices and health care facilities. Safe and appropriate case selection and appropriate dosing for overweight children is also paramount. Oral sedation has been the mainstay of pediatric dental sedation; however, today practitioners are administering modern drugs in new ways with high levels of success. Employing contemporary transmucosal administration devices increases patient acceptance and sedation predictability. While recently there have been many positive developments in sedation technology, it is now thought that medications used in sedation and anesthesia may have adverse effects on the developing brain. The evidence for this is not definitive, but we suggest that practitioners recognize this developing area and counsel patients accordingly. Finally, there is a clear trend of increased use of ambulatory anesthesia services for pediatric dentistry. Today, parents and practitioners have become accustomed to children receiving general anesthesia in the outpatient setting. As a result of these changes, it is possible that dental providers will abandon the practice of personally administering large amounts of

Pediatric dental sedation: challenges and opportunities

Directory of Open Access Journals (Sweden)

Nelson TM

2015-08-01

Full Text Available Travis M Nelson, Zheng Xu Department of Pediatric Dentistry, University of Washington, Seattle, WA, USA Abstract: High levels of dental caries, challenging child behavior, and parent expectations support a need for sedation in pediatric dentistry. This paper reviews modern developments in pediatric sedation with a focus on implementing techniques to enhance success and patient safety. In recent years, sedation for dental procedures has been implicated in a disproportionate number of cases that resulted in death or permanent neurologic damage. The youngest children and those with more complicated medical backgrounds appear to be at greatest risk. To reduce complications, practitioners and regulatory bodies have supported a renewed focus on health care quality and safety. Implementation of high fidelity simulation training and improvements in patient monitoring, including end-tidal carbon dioxide, are becoming recognized as a new standard for sedated patients in dental offices and health care facilities. Safe and appropriate case selection and appropriate dosing for overweight children is also paramount. Oral sedation has been the mainstay of pediatric dental sedation; however, today practitioners are administering modern drugs in new ways with high levels of success. Employing contemporary transmucosal administration devices increases patient acceptance and sedation predictability. While recently there have been many positive developments in sedation technology, it is now thought that medications used in sedation and anesthesia may have adverse effects on the developing brain. The evidence for this is not definitive, but we suggest that practitioners recognize this developing area and counsel patients accordingly. Finally, there is a clear trend of increased use of ambulatory anesthesia services for pediatric dentistry. Today, parents and practitioners have become accustomed to children receiving general anesthesia in the outpatient setting. As a

Comprehensive Validation of Skeletal Mechanism for Turbulent Premixed Methane–Air Flame Simulations

KAUST Repository

Luca, Stefano

2017-08-01

A new skeletal mechanism, consisting of 16 species and 72 reactions, has been developed for lean methane–air premixed combustion from the GRI-Mech 3.0. The skeletal mechanism is validated for elevated unburnt temperatures (800 K) and pressures up to 4 atm, thereby addressing realistic gas turbine conditions. The skeletal mechanism is obtained by applying the directed relation graph method and performing sensitivity analysis on the detailed mechanism. The mechanism has been validated for flame speed and flame structure in a wide range of conditions and configurations. A good agreement between the skeletal mechanism and GRI-3.0 was obtained. The configurations considered include one-dimension laminar premixed flames, laminar non-premixed counterflow burners, and two- and three-dimensional unsteady configurations with variations of temperature, pressure, and composition. The skeletal mechanism allows for the inclusion of accurate finite rate chemistry in large-scale direct numerical simulations of lean turbulent premixed flames. In a large-scale direct numerical simulation, the use of the skeletal mechanism reduces the memory requirements by more than a factor of 3 and accelerates the simulation by a factor of 7 compared with the detailed mechanism. The skeletal mechanism is suitable for unsteady three-dimensional simulations of methane turbulent premixed, non-premixed, and globally lean partially premixed flames and is available as supplementary material.

Pediatric procedural sedation and analgesia

Directory of Open Access Journals (Sweden)

Meredith James

2008-01-01

Full Text Available Procedural sedation and analgesia (PSA is an evolving field in pediatric emergency medicine. As new drugs breach the boundaries of anesthesia in the Pediatric Emergency Department, parents, patients, and physicians are finding new and more satisfactory methods of sedation. Short acting, rapid onset agents with little or no lingering effects and improved safety profiles are replacing archaic regimens. This article discusses the warning signs and areas of a patient′s medical history that are particularly pertinent to procedural sedation and the drugs used. The necessary equipment is detailed to provide the groundwork for implementing safe sedation in children. It is important for practitioners to familiarize themselves with a select few of the PSA drugs, rather than the entire list of sedatives. Those agents most relevant to PSA in the pediatric emergency department are presented.

Intramuscular injection of alfaxalone in combination with butorphanol for sedation in cats.

Science.gov (United States)

Deutsch, Julia; Jolliffe, Colette; Archer, Emma; Leece, Elizabeth A

2017-07-01

To assess quality of sedation following intramuscular (IM) injection of two doses of alfaxalone in combination with butorphanol in cats. Prospective, randomized, 'blinded' clinical study. A total of 38 cats undergoing diagnostic imaging or noninvasive procedures. Cats were allocated randomly to be administered butorphanol 0.2 mg kg -1 combined with alfaxalone 2 mg kg -1 (group AB2) or 5 mg kg -1 (group AB5) IM. If sedation was inadequate, alfaxalone 2 mg kg -1 IM was administered and cats were excluded from further analysis. Temperament [1 (friendly) to 5 (aggressive)], response to injection, sedation score at 2, 6, 8, 15, 20, 30, 40, 50 and 60 minutes, overall sedation quality scored after data collection [1 (excellent) to 4 (inadequate)] and recovery quality were assessed. Heart rate (HR), respiratory rate (f R ) and arterial haemoglobin saturation (SpO 2 ) were recorded every 5 minutes. Groups were compared using t tests and Mann-Whitney U tests. Sedation was analysed using two-way anova, and additional alfaxalone using Fisher's exact test (p cats in AB2 and two in AB5 (p = 0.005). Recovery quality, HR, f R and SpO 2 were similar. Seven cats required oxygen supplementation. Complete recovery times were shorter in AB2 (81.8 ± 24.3 versus 126.6 ± 33.3 minutes; p = 0.009). Twitching was the most common adverse event. In combination with butorphanol, IM alfaxalone at 5 mg kg -1 provided better quality sedation than 2 mg kg -1 . Monitoring of SpO 2 is recommended. Copyright © 2017 Association of Veterinary Anaesthetists and American College of Veterinary Anesthesia and Analgesia. Published by Elsevier Ltd. All rights reserved.

Quantification of extinction mechanism in counterflow premixed flames

International Nuclear Information System (INIS)

Choi, Sang Kyu; Cho, Eun Seong; Chung, Suk Ho

2014-01-01

The extinction mechanisms of stretched premixed flames have been investigated numerically for the fuels of CH 4 , C 3 H 8 , H 2 , CO and for the mixture fuels of CH 4 +H 2 and CO+H 2 by adopting symmetric double premixed flames in a counterflow configuration. The local equilibrium temperature concept was used as a measure of energy loss or gain in order to quantify the extinction mechanism by preferential diffusion and/or incomplete reaction. The energy loss ratio from preferential diffusion arising from non-unity Lewis number and the loss ratio from incomplete reaction were calculated at various equivalence ratios near flame extinction. The results showed that the extinction of lean H 2 , CH 4 , CH 4 +H 2 , CO+H 2 , and rich C 3 H 8 premixed flames was caused by incomplete reaction due to insufficient reaction time, indicating that the effective Lewis number was smaller than unity, while the effect of preferential diffusion resulted in energy gain. However, the extinction of rich H 2 , CH 4 , CH 4 +H 2 , CO+H 2 , and lean C 3 H 8 premixed flames was affected by the combined effects of preferential diffusion and incomplete reaction indicating that the effective Lewis number was larger than unity. In CO premixed flames, incomplete reaction was dominant in both lean and rich cases due to the effective Lewis number close to unity. The effect of H 2 mixing to CO is found to be quite significant as compared to CH 4 +H 2 cases, which can alter the flame behavior of CO flames to that of H 2 .

Quantification of extinction mechanism in counterflow premixed flames

KAUST Repository

Choi, Sangkyu

2014-09-01

The extinction mechanisms of stretched premixed flames have been investigated numerically for the fuels of CH4, C3H8, H2, CO and for the mixture fuels of CH4+H2 and CO+H2 by adopting symmetric double premixed flames in a counterflow configuration. The local equilibrium temperature concept was used as a measure of energy loss or gain in order to quantify the extinction mechanism by preferential diffusion and/or incomplete reaction. The energy loss ratio from preferential diffusion arising from non-unity Lewis number and the loss ratio from incomplete reaction were calculated at various equivalence ratios near flame extinction. The results showed that the extinction of lean H2, CH4, CH4+H2, CO+H2, and rich C3H8 premixed flames was caused by incomplete reaction due to insufficient reaction time, indicating that the effective Lewis number was smaller than unity, while the effect of preferential diffusion resulted in energy gain. However, the extinction of rich H2, CH4, CH4+H2, CO+H2, and lean C3H8 premixed flames was affected by the combined effects of preferential diffusion and incomplete reaction indicating that the effective Lewis number was larger than unity. In CO premixed flames, incomplete reaction was dominant in both lean and rich cases due to the effective Lewis number close to unity. The effect of H2 mixing to CO is found to be quite significant as compared to CH4+H2 cases, which can alter the flame behavior of CO flames to that of H2.

Chaos in an imperfectly premixed model combustor.

Science.gov (United States)

Kabiraj, Lipika; Saurabh, Aditya; Karimi, Nader; Sailor, Anna; Mastorakos, Epaminondas; Dowling, Ann P; Paschereit, Christian O

2015-02-01

This article reports nonlinear bifurcations observed in a laboratory scale, turbulent combustor operating under imperfectly premixed mode with global equivalence ratio as the control parameter. The results indicate that the dynamics of thermoacoustic instability correspond to quasi-periodic bifurcation to low-dimensional, deterministic chaos, a route that is common to a variety of dissipative nonlinear systems. The results support the recent identification of bifurcation scenarios in a laminar premixed flame combustor (Kabiraj et al., Chaos: Interdiscip. J. Nonlinear Sci. 22, 023129 (2012)) and extend the observation to a practically relevant combustor configuration.

Comparison of Dexmedetomidine and Midazolam in Sedation for Percutaneous Drainage of Hepatic Hydatid Cysts.

Science.gov (United States)

Bavullu, Emine Nilgün; Aksoy, Esra; Abdullayev, Ruslan; Göğüş, Nermin; Dede, Doğan

2013-12-01

Hydatid cyst still continues to be a public health problem. The basic treatment for the disease is surgery, but ultrasound-guided percutaneous drainage has become an important treatment alternative. Agents preferred for sedation during drainage performed under local anaesthesia must also preserve respiration and hemodynamic stability while providing adequate sedation. We compared the sedative properties of midazolam, which has a short duration of action, and a selective α2 adrenergic receptor agonist, dexmedetomidine, and the intraoperative complications. After approval by the clinical trials ethics committee, 40 patients with similar demographic data were randomized into two groups. All patients received 10 mg metoclopramide and 45.5 mg pheniramine before the procedure. Then, midazolam (0.07 mg kg(-1) IV bolus followed by 0.01 mg kg(-1) h(-1) infusion) was administered to Group 1, and dexmedetomidine (1 μg kg(-1) loading dose in 10 minutes, followed by 0.2 μg kg(-1) h(-1) continuous infusion) was administered to Group 2 for sedation. Just before the surgical procedure, all patients received IV propofol in a subhypnotic dose of 0.5 mg kg(-1); the dose was repeated if adequate sedation could not be achieved. Observer's assessment of alertness/sedation (OAA/S) scale and Bispectral index (BIS) were used to evaluate the sedation level during the procedure. Heart rate (HR), mean arterial pressure (MAP), respiratory rate (RR), peripheral oxygen saturation (SpO2) and end-tidal carbon dioxide pressure (ETCO2) were monitored before and after induction and every 5 minutes thereafter. Propofol requirement was noted for each group. Sedation in the dexmedetomidine group was as effective and adequate as that observed in the midazolam group. BIS values were significantly lower in the dexmedetomidine group, especially after 10 minutes and thereafter. RR, SpO2, and ETCO2 were similar in both groups, whereas clinically insignificant decreases in HR and MAP were observed in the

Non-sedation versus sedation with a daily wake-up trial in critically ill patients receiving mechanical ventilation (NONSEDA Trial)

DEFF Research Database (Denmark)

Toft, Palle; Olsen, Hanne Tanghus; Jørgensen, Helene Korvenius

2014-01-01

comparing sedation with no sedation, a priori powered to have all-cause mortality as primary outcome.The objective is to assess the benefits and harms of non-sedation versus sedation with a daily wake-up trial in critically ill patients. METHODS: The non-sedation (NONSEDA) trial is an investigator......-sedation supplemented with pain management during mechanical ventilation.Control intervention is sedation with a daily wake-up trial.The primary outcome will be all cause mortality at 90 days after randomization. Secondary outcomes will be: days until death throughout the total observation period; coma- and delirium...... in mortality with a type I error risk of 5% and a type II error risk of 20% (power at 80%). DISCUSSION: The trial investigates potential benefits of non-sedation. This might have large impact on the future treatment of mechanically ventilated critically ill patients.Trial register: ClinicalTrials.gov NCT...

A Review of Palliative Sedation.

Science.gov (United States)

Bobb, Barton

2016-09-01

Palliative sedation has become a standard practice to treat refractory symptoms at end-of-life. Dyspnea and delirium are the two most commonly treated symptoms. The medications used in palliative sedation are usually benzodiazepines, barbiturates, antipsychotics, and/or anesthetics. Some ethical considerations remain, especially surrounding the use of palliative sedation in psychological distress and existential suffering. Copyright © 2016 Elsevier Inc. All rights reserved.

Study on Combustion Oscillation of Premixed Flame with Pilot Fuel at Elevated Pressures

Science.gov (United States)

Ohtsuka, Masaya; Yoshida, Shohei; Hirata, Yoshitaka; Kobayashi, Nariyoshi

Acoustically-coupled combustion oscillation is studied for premixed flame with pilot fuel to be used in gas turbine combustors. Premixed gas is passed through swirl vanes and burnt with the centrally injected pilot fuel. The dependencies of pressure, fuel to air ratio, premixed fuel rate, inlet velocity and air temperature on the combustion oscillation are investigated. Two kinds of oscillation modes of ˜100Hz and ˜350Hz are activated according to inlet velocities. Fluctuating pressures are amplified when the premixed fuel rate is over ˜80% at elevated pressures. The fluctuating pressure peak moves to a higher premixed fuel ratio region with increased pressure or fuel to air ratio for the Helmholz type mode. Combustion oscillation occurs when the pilot fuel velocity is changed proportionally with the flame length.

Therapeutics and Sedation in Dentistry

OpenAIRE

Young, Earle R.

1988-01-01

Sedation can help to overcome the fear that prevents many Canadians from accepting dental treatment. This article discusses the indications and contraindications for oral, intramuscular, and inhalation sedation as used by the general dental practitioner for both adult and child patients, with a note on the growing number of specialist dental anesthetists who provide intravenous out-patient sedation. Local anesthesia is discussed with reference to allergic reactions, malignant hyperthermia, an...

Recall of intensive care unit stay in patients managed with a sedation protocol or a sedation protocol with daily sedative interruption: a pilot study.

Science.gov (United States)

Ethier, Cheryl; Burry, Lisa; Martinez-Motta, Carlos; Tirgari, Sam; Jiang, Depeng; McDonald, Ellen; Granton, John; Cook, Deborah; Mehta, Sangeeta

2011-04-01

Analgesics and sedatives are integral for the relief of pain and anxiety in critically ill patients. However, these agents may contribute to amnesia for intensive care unit (ICU) events; which has been associated with development of posttraumatic stress disorder. Drug administration strategies that minimize sedative use have been associated with less amnesia. The objective of this pilot study was to evaluate recall of ICU stay in patients managed with 2 sedation strategies: a sedation protocol or a combination of sedation protocol and daily sedative/analgesic interruption. A questionnaire was administered on day 3 following ICU discharge to evaluate patients' recollections of pain, anxiety, fear, and sleep, as well as memories for specific ICU procedures. Participants were ICU survivors who had been enrolled in SLEAP - a randomized pilot trial comparing two sedation strategies, at 3 university-affiliated medical/surgical ICUs. Twenty-one patients who regained orientation within 72 hours of ICU discharge completed the questionnaire. More than 50% of patients recalled experiencing pain, anxiety, and fear to a moderate or extreme extent; and 57% reported inadequate sleep while in the ICU. Of the 21 patients, 48%, 33%, and 29% had no memories of endotracheal tube suctioning, being on a "breathing machine," and being bathed, respectively. A notable percentage of patients discharged from the ICU report moderate to extreme pain, anxiety, and fear, and inability to sleep during their ICU stay; and 29% to 48% have no recall of specific ICU events. Copyright © 2011 Elsevier Inc. All rights reserved.

Euthanasia and palliative sedation in Belgium.

Science.gov (United States)

Cohen-Almagor, Raphael; Ely, E Wesley

2018-01-04

The aim of this article is to use data from Belgium to analyse distinctions between palliative sedation and euthanasia. There is a need to reduce confusion and improve communication related to patient management at the end of life specifically regarding the rapidly expanding area of patient care that incorporates a spectrum of nuanced yet overlapping terms such as palliative care, sedation, palliative sedation, continued sedation, continued sedation until death, terminal sedation, voluntary euthanasia and involuntary euthanasia. Some physicians and nurses mistakenly think that relieving suffering at the end of life by heavily sedating patients is a form of euthanasia, when indeed it is merely responding to the ordinary and proportionate needs of the patient. Concerns are raised about abuse in the form of deliberate involuntary euthanasia, obfuscation and disregard for the processes sustaining the management of refractory suffering at the end of life. Some suggestions designed to improve patient management and prevent potential abuse are offered. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Quantification of extinction mechanism in counterflow premixed flames

Energy Technology Data Exchange (ETDEWEB)

Choi, Sang Kyu [Korea Institute of Machinery and Materials, Daejeon (Korea, Republic of); Cho, Eun Seong [Doosan Heavy Industries and Construction, Changwon (Korea, Republic of); Chung, Suk Ho [Abdullah University of Science and Technology, Thuwal (Saudi Arabia)

2014-09-15

The extinction mechanisms of stretched premixed flames have been investigated numerically for the fuels of CH{sub 4}, C{sub 3}H{sub 8}, H{sub 2}, CO and for the mixture fuels of CH{sub 4}+H{sub 2} and CO+H{sub 2} by adopting symmetric double premixed flames in a counterflow configuration. The local equilibrium temperature concept was used as a measure of energy loss or gain in order to quantify the extinction mechanism by preferential diffusion and/or incomplete reaction. The energy loss ratio from preferential diffusion arising from non-unity Lewis number and the loss ratio from incomplete reaction were calculated at various equivalence ratios near flame extinction. The results showed that the extinction of lean H{sub 2} , CH{sub 4}, CH{sub 4}+H{sub 2}, CO+H{sub 2}, and rich C{sub 3}H{sub 8} premixed flames was caused by incomplete reaction due to insufficient reaction time, indicating that the effective Lewis number was smaller than unity, while the effect of preferential diffusion resulted in energy gain. However, the extinction of rich H{sub 2}, CH{sub 4}, CH{sub 4}+H{sub 2}, CO+H{sub 2}, and lean C{sub 3}H{sub 8} premixed flames was affected by the combined effects of preferential diffusion and incomplete reaction indicating that the effective Lewis number was larger than unity. In CO premixed flames, incomplete reaction was dominant in both lean and rich cases due to the effective Lewis number close to unity. The effect of H{sub 2} mixing to CO is found to be quite significant as compared to CH{sub 4}+H{sub 2} cases, which can alter the flame behavior of CO flames to that of H{sub 2}.

Procedural sedation analgesia

OpenAIRE

Sheta, Saad A

2010-01-01

The number of noninvasive and minimally invasive procedures performed outside of the operating room has grown exponentially over the last several decades. Sedation, analgesia, or both may be needed for many of these interventional or diagnostic procedures. Individualized care is important when determining if a patient requires procedural sedation analgesia (PSA). The patient might need an anti-anxiety drug, pain medicine, immobilization, simple reassurance, or a combination of these interve...

Cultural changes in ICU sedation management

DEFF Research Database (Denmark)

Egerod, Ingrid

2009-01-01

The aim of this study was to explore physicians' views and perceptions of sedation, and offer a new approach to the understanding of issues of sedation. I used a qualitative, descriptive, and explorative multicenter design. Data were generated by seven key-informant interviews using...... a semistructured interview guide. One experienced doctor was selected at each of the seven largest intensive care units in Denmark. Interpretational analysis was performed by comprehensive overview, individual case analysis, cross-case analysis, and integrated thematic analysis and identification of emerging...... provide an understanding of contextual issues of sedation, safety, and comfort, and suggest that a cultural change in sedation strategies might reduce the duration of sedation and mechanical ventilation while containing cost and improving the well-being of the patients....

Palliative sedation: not just normal medical practice. Ethical reflections on the Royal Dutch Medical Association's guideline on palliative sedation.

Science.gov (United States)

Janssens, Rien; van Delden, Johannes J M; Widdershoven, Guy A M

2012-11-01

The main premise of the Royal Dutch Medical Association's (RDMA) guideline on palliative sedation is that palliative sedation, contrary to euthanasia, is normal medical practice. Although we do not deny the ethical distinctions between euthanasia and palliative sedation, we will critically analyse the guideline's argumentation strategy with which euthanasia is demarcated from palliative sedation. First, we will analyse the guideline's main premise, which entails that palliative sedation is normal medical treatment. After this, we will critically discuss three crucial propositions of the guideline that are used to support this premise: (1) the patient's life expectancy should not exceed 2 weeks; (2) the aim of the physician should be to relieve suffering and (3) expert consultation is optional. We will conclude that, if inherent problematic aspects of palliative sedation are taken seriously, palliative sedation is less normal than it is now depicted in the guideline.

'Palliative sedation'? A retrospective cohort study on the use and labelling of continuously administered sedatives on a palliative care unit.

Science.gov (United States)

Schildmann, Eva; Pörnbacher, Sebastian; Kalies, Helen; Bausewein, Claudia

2018-03-01

Sedatives are frequently used towards the end of life. However, there is scarce information when their use is labelled as 'palliative sedation'. To assess the use and labelling of 'continuous administration of sedatives within the last 7 days of life', based on objective operational criteria, on a palliative care unit. Retrospective cohort study, using medical records. Explorative statistical analysis (SPSS 23). Patients who died on a palliative care unit from August 2014 to July 2015. Sedatives recorded were benzodiazepines, levomepromazine, haloperidol ⩾5 mg/day and propofol. Of the 192 patients, 149 (78%) patients received continuous sedatives within the last week of life. The prevalence of delirium/agitation was significantly higher in patients with continuous sedatives compared to those without continuous sedatives at admission to the unit (35% vs 16%, p = 0.02) and on the day before death (58% vs 40%, p = 0.04). The term '(palliative) sedation' was used in the records for 22 of 149 (15%) patients with continuous sedatives. These patients had significantly higher total daily midazolam doses 2 days before death (median (range), 15.0 (6.0-185.0) mg vs 11.5 (1.0-70.0) mg, p = 0.04) and on the day of death (median (range), 19.5 (7.5-240.0) mg vs 12.5 (2.0-65.0) mg, p = 0.01). The dose range was large in both groups. The prevalence of delirium/agitation was associated with the administration of continuous sedatives. There was no consistent pattern regarding labelling the use of continuous sedatives as '(palliative) sedation'. Multicentre mixed-methods research is needed for a better characterization of sedation practices in palliative care.

[Sedation with midazolam for ambulatory pediatric dentistry].

Science.gov (United States)

Shavlokhova, E A; Ostreĭkov, I F; Korolenkova, M V

2014-01-01

To improve the quality of dental treatment in children by using combined anaesthesia technique including local anaesthesia and conscious sedation, and to assess the effectiveness of conscious sedation for younger children undergoing dental treatment. The study included 208 children aged 14-88 months who received dental treatment for tooth decay and its complication under combined anaesthesia. Midazolam was used as sedative medication. Sedation level was assessed by visual scale and BIS-monitoring. ANI-monitoring was also used for pain sensitiveness evaluation. Results All 208 children were successfully treated under combined anaesthesia which showed satisfactory sedation rates both by visual scale and and BIS-monitoring values. While mean patient age was 39 months 20.6% were younger than 24 months. These data are extremely valuable as according to literature review conscious sedation in early infancy remains controversial. Our results proved conscious sedation to be effective in younger children undergoing dental treatment thus representing important alternative for general anaesthesia and providing a basis for later behavior management.

Nurse-administered propofol sedation for endoscopy

DEFF Research Database (Denmark)

Jensen, J T; Vilmann, P; Horsted, T

2011-01-01

BACKGROUND AND STUDY AIMS: The aim of the present study was to perform a risk analysis during the implementation phase of nurse-administered propofol sedation (NAPS) and to validate our structured training program. PATIENTS AND METHODS: A structured training program was developed both for endosco......BACKGROUND AND STUDY AIMS: The aim of the present study was to perform a risk analysis during the implementation phase of nurse-administered propofol sedation (NAPS) and to validate our structured training program. PATIENTS AND METHODS: A structured training program was developed both...... pressure was recorded in 451 patients (26%). Independent risk factors were type of intervention and level of experience of the staff performing the sedation. CONCLUSION: These results were obtained after development of a structured training program both for endoscopists and nurses using propofol...... for sedation, and can be used as basis for further comparison. NAPS for endoscopic procedures is safe when performed by personnel properly trained in airway handling and sedation with propofol, and has considerable advantages compared with conventional sedation for endoscopy....

High-Flow Nasal Oxygen in Patient With Obstructive Sleep Apnea Undergoing Awake Craniotomy: A Case Report.

Science.gov (United States)

Wong, Jaclyn W M; Kong, Amy H S; Lam, Sau Yee; Woo, Peter Y M

2017-12-15

Patients with obstructive sleep apnea are frequently considered unsuitable candidates for awake craniotomy due to anticipated problems with oxygenation, ventilation, and a potentially difficult airway. At present, only a handful of such accounts exist in the literature. Our report describes the novel use of high-flow nasal oxygen therapy for a patient with moderate obstructive sleep apnea who underwent an awake craniotomy under deep sedation. The intraoperative application of high-flow nasal oxygen therapy achieved satisfactory oxygenation, maintained the partial carbon dioxide pressure within a reasonable range even during periods of deep sedation, permitted responsive patient monitoring during mapping, and provided excellent patient and surgeon satisfaction.

Gravity Effects Observed In Partially Premixed Flames

Science.gov (United States)

Puri, Ishwar K.; Aggarwal, Suresh K.; Lock, Andrew J.; Gauguly, Ranjan; Hegde, Uday

2003-01-01

Partially premixed flames (PPFs) contain a rich premixed fuel air mixture in a pocket or stream, and, for complete combustion to occur, they require the transport of oxidizer from an appropriately oxidizer-rich (or fuel-lean) mixture that is present in another pocket or stream. Partial oxidation reactions occur in fuel-rich portions of the mixture and any remaining unburned fuel and/or intermediate species are consumed in the oxidizer-rich portions. Partial premixing, therefore, represents that condition when the equivalence ratio (phi) in one portion of the flowfield is greater than unity, and in another section its value is less than unity. In general, for combustion to occur efficiently, the global equivalence ratio is in the range fuel-lean to stoichiometric. These flames can be established by design by placing a fuel-rich mixture in contact with a fuel-lean mixture, but they also occur otherwise in many practical systems, which include nonpremixed lifted flames, turbulent nonpremixed combustion, spray flames, and unwanted fires. Other practical applications of PPFs are reported elsewhere. Although extensive experimental studies have been conducted on premixed and nonpremixed flames under microgravity, there is a absence of previous experimental work on burner stabilized PPFs in this regard. Previous numerical studies by our group employing a detailed numerical model showed gravity effects to be significant on the PPF structure. We report on the results of microgravity experiments conducted on two-dimensional (established on a Wolfhard-Parker slot burner) and axisymmetric flames (on a coannular burner) that were investigated in a self-contained multipurpose rig. Thermocouple and radiometer data were also used to characterize the thermal transport in the flame.

Sedation in Pediatric Esophagogastroduodenoscopy

Directory of Open Access Journals (Sweden)

Seak Hee Oh

2018-03-01

Full Text Available Pediatric esophagogastroduodenoscopy (EGD has become an established diagnostic and therapeutic modality in pediatric gastroenterology. Effective sedation strategies have been adopted to improve patient tolerance during pediatric EGD. For children, safety is a fundamental consideration during this procedure as they are at a higher risk of severe adverse events from procedural sedation compared to adults. Therefore, a detailed risk evaluation is required prior to the procedure, and practitioners should be aware of the benefits and risks associated with sedation regimens during pediatric EGD. In addition, pediatric advanced life support by endoscopists or immediate intervention by anesthesiologists should be available in the event that severe adverse events occur during pediatric EGD.

The Effect of Intravenous Dexmedetomidine on Spinal Block and Sedation

Directory of Open Access Journals (Sweden)

Abdurrahman Ekici

2015-03-01

Material and Methods: Our randomised, double-blind study was applied to ASA I-III, 18-75 years old 50 patients scheduled for transurethral surgery. The patients were divided into two groups and spinal anesthesia with 5% levobupivacaine 12.5 mg was administered to all patients. Intravenous dexmedetomidine was received 1 and micro;g/kg for loading dose before 0.5 and micro;g/kg/hour infusion to Group D (n=25. Saline infusion was given 1 and micro;g/kg for loading dose before 0.5 and micro;g/kg/hour infusion to Group S (n=25. Systolic, diastolic and mean arterial pressure, heart rate, peripheral oxygen saturation values, pain and sedation score, the level and duration of motor and sensorial block, recovery and patient comfort score and side effects were recorded. Results: Time to reach maximum block level and duration of spinal anesthesia were longer in Group D than Group S. Sedation scores were significantly higher in Group D than Group S intraoperatively (except 1th minute and postoperatively 10th and 15th minutes. The incidence of side effects, postoperative recovery and patient comfort values were similar between the groups. Conclusion: We found that dexmedetomidine prolongs duration of motor block, provides safe and effective sedation without increasing the incidence of side effect in the patients under spinal anesthesia. [Cukurova Med J 2015; 40(1.000: 55-62

ASAP ECMO: Antibiotic, Sedative and Analgesic Pharmacokinetics during Extracorporeal Membrane Oxygenation: a multi-centre study to optimise drug therapy during ECMO

Directory of Open Access Journals (Sweden)

Shekar Kiran

2012-11-01

Full Text Available Abstract Background Given the expanding scope of extracorporeal membrane oxygenation (ECMO and its variable impact on drug pharmacokinetics as observed in neonatal studies, it is imperative that the effects of the device on the drugs commonly prescribed in the intensive care unit (ICU are further investigated. Currently, there are no data to confirm the appropriateness of standard drug dosing in adult patients on ECMO. Ineffective drug regimens in these critically ill patients can seriously worsen patient outcomes. This study was designed to describe the pharmacokinetics of the commonly used antibiotic, analgesic and sedative drugs in adult patients receiving ECMO. Methods/Design This is a multi-centre, open-label, descriptive pharmacokinetic (PK study. Eligible patients will be adults treated with ECMO for severe cardiac and/or respiratory failure at five Intensive Care Units in Australia and New Zealand. Patients will receive the study drugs as part of their routine management. Blood samples will be taken from indwelling catheters to investigate plasma concentrations of several antibiotics (ceftriaxone, meropenem, vancomycin, ciprofloxacin, gentamicin, piperacillin-tazobactum, ticarcillin-clavulunate, linezolid, fluconazole, voriconazole, caspofungin, oseltamivir, sedatives and analgesics (midazolam, morphine, fentanyl, propofol, dexmedetomidine, thiopentone. The PK of each drug will be characterised to determine the variability of PK in these patients and to develop dosing guidelines for prescription during ECMO. Discussion The evidence-based dosing algorithms generated from this analysis can be evaluated in later clinical studies. This knowledge is vitally important for optimising pharmacotherapy in these most severely ill patients to maximise the opportunity for therapeutic success and minimise the risk of therapeutic failure. Trial registration ACTRN12612000559819

Conscious sedation for patients undergoing enteroclysis: Comparing the safety and patient-reported effectiveness of two protocols

International Nuclear Information System (INIS)

Maglinte, Dean D.T.; Applegate, Kimberly E.; Rajesh, Arumugam; Jennings, S. Gregory; Ford, Jason M.; Savabi, Mojgan Sarah; Lappas, John C.

2009-01-01

Objective: To compare the safety and patient-reported effectiveness of two regimens for conscious sedation during enteroclysis. Materials and methods: We surveyed two groups of outpatients and retrospectively reviewed procedure records for conscious sedation and complications. Patients were divided into Group One (received sedative/amnesic diazepam), and Group Two, (received amnesic/sedative, midazolam and analgesic fentanyl). Results: All enteroclyses were successfully completed; there were no hospital admissions due to complications. In Group One (n = 106), mean dose of diazepam was 12.7 mg. 25% had oxygen desaturation (n = 25), and post-procedure vomiting without aspiration (n = 1). 56% of outpatients completed phone surveys, and 68% recalled procedural discomfort. In Group Two (n = 45), mean doses were 3.9 mg midazolam and 108 mcg fentanyl. 31% had desaturation (n = 13), and post-procedure vomiting without aspiration (n = 1). 87% had only a vague recall of the procedure or of any discomfort. Conclusion: A combination of amnesic and fentanyl prevented the recall of discomfort of nasoenteric intubation and infusion in most patients who had enteroclysis compared to diazepam. Most of the patients would undergo the procedure again, if needed.

Conscious sedation for patients undergoing enteroclysis: Comparing the safety and patient-reported effectiveness of two protocols

Energy Technology Data Exchange (ETDEWEB)

Maglinte, Dean D.T. [Department of Radiology, Indiana University Medical Center, 550 N, University Boulevard, University Hospital Room 0279, Indianapolis, IN 46202-5253 (United States)], E-mail: dmaglint@iupui.edu; Applegate, Kimberly E.; Rajesh, Arumugam; Jennings, S. Gregory; Ford, Jason M. [Department of Radiology, Indiana University Medical Center, 550 N, University Boulevard, University Hospital Room 0279, Indianapolis, IN 46202-5253 (United States); Savabi, Mojgan Sarah [Division of Gastroenterology, Department of Medicine, Indiana University School of Medicine, 550 N, University Boulevard, Indianapolis, IN 46202-5253 (United States); Lappas, John C. [Department of Radiology, Indiana University Medical Center, 550 N, University Boulevard, University Hospital Room 0279, Indianapolis, IN 46202-5253 (United States)

2009-06-15

Objective: To compare the safety and patient-reported effectiveness of two regimens for conscious sedation during enteroclysis. Materials and methods: We surveyed two groups of outpatients and retrospectively reviewed procedure records for conscious sedation and complications. Patients were divided into Group One (received sedative/amnesic diazepam), and Group Two, (received amnesic/sedative, midazolam and analgesic fentanyl). Results: All enteroclyses were successfully completed; there were no hospital admissions due to complications. In Group One (n = 106), mean dose of diazepam was 12.7 mg. 25% had oxygen desaturation (n = 25), and post-procedure vomiting without aspiration (n = 1). 56% of outpatients completed phone surveys, and 68% recalled procedural discomfort. In Group Two (n = 45), mean doses were 3.9 mg midazolam and 108 mcg fentanyl. 31% had desaturation (n = 13), and post-procedure vomiting without aspiration (n = 1). 87% had only a vague recall of the procedure or of any discomfort. Conclusion: A combination of amnesic and fentanyl prevented the recall of discomfort of nasoenteric intubation and infusion in most patients who had enteroclysis compared to diazepam. Most of the patients would undergo the procedure again, if needed.

Intranasal sedatives in pediatric dentistry

Science.gov (United States)

AlSarheed, Maha A.

2016-01-01

Objectives: To identify the intranasal (IN) sedatives used to achieve conscious sedation during dental procedures amongst children. Methods: A literature review was conducted by identifying relevant studies through searches on Medline. Search included IN of midazolam, ketamine, sufentanil, dexmedetomidine, clonidine, haloperidol and loranzepam. Studies included were conducted amongst individuals below 18 years, published in English, and were not restricted by year. Exclusion criteria were articles that did not focus on pediatric dentistry. Results: Twenty studies were included. The most commonly used sedatives were midazolam, followed by ketamine and sufentanil. Onset of action for IN midazolam was 5-15 minutes (min), however, IN ketamine was faster (mean 5.74 min), while both IN sufentanil (mean 20 min) and IN dexmedetomidine (mean 25 min) were slow in comparison. Midazolam was effective for modifying behavior in mild to moderately anxious children, however, for more invasive or prolonged procedures, stronger sedatives, such as IN ketamine, IN sufentanil were recommended. In addition, ketamine fared better in overall success rate (89%) when compared with IN midazolam (69%). Intranasal dexmedetomidine was only used as pre-medication amongst children. While its’ onset of action is longer when compared with IN midazolam, it produced deeper sedation at the time of separation from the parent and at the time of anesthesia induction. Conclusion: Intranasal midazolam, ketamine and sufentanil are effective and safe for conscious sedation, while intranasal midazolam, dexmedetomidine and sufentanil have proven to be effective premedications. PMID:27570849

Sedation for procedures outside the operating room in children

International Nuclear Information System (INIS)

Molina Rodriguez, Ericka

2014-01-01

Sedation is defined in the pediatric population. An adequate preoperative assessment is established in patients subjected to a sedation. Fundamental characteristics of drugs used during a sedation are determined. Recommendations about surveillance and monitoring are established in a patient sedated. Principal characteristics of sedation are defined in patients exposed to radiological diagnostic and therapeutic procedures. Considerations in sedation are identified for procedures in the laboratory of digestive endoscopy. Alternatives of sedation are mentioned for oncological patients subjected to invasive procedures. Working conditions and specifications of anesthesia are determined in the cardiac catheterization room [es

Palliative pharmacological sedation for terminally ill adults.

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Beller, Elaine M; van Driel, Mieke L; McGregor, Leanne; Truong, Shani; Mitchell, Geoffrey

2015-01-02

Terminally ill people experience a variety of symptoms in the last hours and days of life, including delirium, agitation, anxiety, terminal restlessness, dyspnoea, pain, vomiting, and psychological and physical distress. In the terminal phase of life, these symptoms may become refractory, and unable to be controlled by supportive and palliative therapies specifically targeted to these symptoms. Palliative sedation therapy is one potential solution to providing relief from these refractory symptoms. Sedation in terminally ill people is intended to provide relief from refractory symptoms that are not controlled by other methods. Sedative drugs such as benzodiazepines are titrated to achieve the desired level of sedation; the level of sedation can be easily maintained and the effect is reversible. To assess the evidence for the benefit of palliative pharmacological sedation on quality of life, survival, and specific refractory symptoms in terminally ill adults during their last few days of life. We searched the Cochrane Central Register of Controlled Trials (CENTRAL; 2014, Issue 11), MEDLINE (1946 to November 2014), and EMBASE (1974 to December 2014), using search terms representing the sedative drug names and classes, disease stage, and study designs. We included randomised controlled trials (RCTs), quasi-RCTs, non-RCTs, and observational studies (e.g. before-and-after, interrupted-time-series) with quantitative outcomes. We excluded studies with only qualitative outcomes or that had no comparison (i.e. no control group or no within-group comparison) (e.g. single arm case series). Two review authors independently screened titles and abstracts of citations, and full text of potentially eligible studies. Two review authors independently carried out data extraction using standard data extraction forms. A third review author acted as arbiter for both stages. We carried out no meta-analyses due to insufficient data for pooling on any outcome; therefore, we reported

Use of Piggyback Electrolytes for Patients Receiving Individually Prescribed vs Premixed Parenteral Nutrition.

Science.gov (United States)

Busch, Rebecca A; Curtis, Caitlin S; Leverson, Glen E; Kudsk, Kenneth A

2015-07-01

Parenteral nutrition (PN) is available as individualized prescriptions frequently prepared with an automated compounding device or as commercially prepared premixed solutions. Our institution exclusively used individualized PN until an amino acid shortage forced a temporary switch to premixed solutions. In general, premixed solutions contain lower electrolyte levels than individualized formulations prescribed for patients with normal organ function. We aimed to quantify supplemental intravenous piggyback (IVPB) electrolyte use in adult patients receiving individualized and premixed PN and to quantify any effect on difference in the cost of therapy. We compared use of supplemental IVPB electrolytes administered to patients receiving PN during consecutive periods prior to and during the amino acid shortage. Electrolyte IVPBs tabulated were potassium chloride, 10 and 20 mEq; magnesium sulfate, 2 g and 4 g; potassium phosphate, 7.5 and 15 mmol; and sodium phosphate, 7.5 and 15 mmol IVPB. There was no statistical difference in the number of PN formulations administered per day during each period (14.7 ± 3.9 vs 14.0 ± 2.6, individualized vs premixed, respectively). Total IVPB electrolytes prescribed per day increased significantly from the individualized PN period to the premixed PN period (7.03 ± 3.8 vs 13.8 ± 6.8; P Parenteral and Enteral Nutrition.

Analgesic efficacy of equimolar 50% nitrous oxide/oxygen gas premix (Kalinox®) as compared with a 5% eutectic mixture of lidocaine/prilocaine (EMLA®) in chronic leg ulcer debridement.

Science.gov (United States)

Traber, Juerg; Held, Ulrike; Signer, Maria; Huebner, Tobias; Arndt, Stefan; Neff, Thomas A

2017-08-01

Chronic foot and leg ulcers are a common health problem worldwide. A mainstay of chronic ulcer therapy is sharp mechanical wound debridement requiring potent analgesia. In this prospective, controlled, single-centre, crossover design study, patients were assigned to either the administration of topical analgesia with 5% lidocaine/prilocaine cream or the inhalation of an analgesic 50% N 2 O/O 2 gas premix. Primary outcome parameter was level of pain at maximum wound depth during debridement as measured by a visual analogue scale. Secondary outcomes included level of pain after debridement, overall duration of treatment session, duration and completeness of debridement, and the patient's subjective perception of analgesic quality during debridement. Pain level increased from 0·60/0·94 (first/second debridement; baseline) to 1·76/2·50 (debridement) with 5% lidocaine/prilocaine and from 1·00/1·35 (baseline) to 3·95/3·29 (debridement) with 50% N 2 O/O 2 gas premix. Patient satisfaction was 90·48%/94·44% (first/second debridement) with topical 5% lidocaine/prilocaine analgesia and 90·48%/76·47% with the inhalation of 50% N 2 O/O 2 gas premix. Debridement was completed in a significantly higher percentage of 85·71%/88·89% (first/second debridement) with 5% lidocaine/prilocaine than with 50% N 2 O/O 2 gas premix (42·86%/58·82%) (odds ratio 6·7; P = 0·001). This study provides sound evidence that analgesia with topically administered 5% lidocaine/prilocaine cream is superior to the use of inhaled 50% N 2 O/O 2 gas premix in chronic leg ulcer debridement. © 2016 Medicalhelplines.com Inc and John Wiley & Sons Ltd.

Færre indikationer for sedation ved respiratorbehandling

DEFF Research Database (Denmark)

Strøm, Thomas; Rian, Omar; Toft, Palle

2012-01-01

Critically ill patients undergoing mechanical ventilation have traditionally been deeply sedated. In the latest decade growing evidence supports less sedation as being beneficial for the patients. A daily interruption of sedation has been shown to reduce the length of mechanical ventilation and t...

Palliative sedation versus euthanasia: an ethical assessment.

Science.gov (United States)

ten Have, Henk; Welie, Jos V M

2014-01-01

The aim of this article was to review the ethical debate concerning palliative sedation. Although recent guidelines articulate the differences between palliative sedation and euthanasia, the ethical controversies remain. The dominant view is that euthanasia and palliative sedation are morally distinct practices. However, ambiguous moral experiences and considerable practice variation call this view into question. When heterogeneous sedative practices are all labeled as palliative sedation, there is the risk that palliative sedation is expanded to include practices that are actually intended to bring about the patients' death. This troublesome expansion is fostered by an expansive use of the concept of intention such that this decisive ethical concept is no longer restricted to signify the aim in guiding the action. In this article, it is argued that intention should be used in a restricted way. The significance of intention is related to other ethical parameters to demarcate the practice of palliative sedation: terminality, refractory symptoms, proportionality, and separation from other end-of-life decisions. These additional parameters, although not without ethical and practical problems, together formulate a framework to ethically distinguish a more narrowly defined practice of palliative sedation from practices that are tantamount to euthanasia. Finally, the article raises the question as to what impact palliative sedation might have on the practice of palliative care itself. The increasing interest in palliative sedation may reemphasize characteristics of health care that initially encouraged the emergence of palliative care in the first place: the focus on therapy rather than care, the physical dimension rather than the whole person, the individual rather than the community, and the primacy of intervention rather than receptiveness and presence. Copyright © 2014 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Propofol sedation in children: sleep trumps amnesia☆

Science.gov (United States)

Veselis, Robert; Kelhoffer, Eric; Mehta, Meghana; Root, James C.; Robinson, Fay; Mason, Keira P.

2017-01-01

Objective Detailed assessments of the effects of propofol on memory in children are lacking. We assessed the feasibility of measuring memory during propofol infusion, as commonly performed in sedation for MRI scanning. In addition, we determined the onset of memory loss in relation to the onset of sedation measured by verbal responsiveness. Materials and methods Children scheduled for sedation for MRI received a 10-min infusion of propofol (3 mg/kg) as they viewed and named 100 simple line drawings, one shown every five seconds, until they were no longer responsive (encoding). A control group receiving no sedation for MRI underwent similar tasks. Sedation was measured as any verbal response, regardless of correctness. After recovery from sedation, recognition memory was tested, with correct yes/no recognitions matched to sedation responses during encoding (subsequent memory paradigm). Results Of the 48 children who received propofol, 30 could complete all study tasks (6.2 ± 1.6 years, 16 males). Individual responses could be modeled in all 30 children. On average, there was a 50% probability of no verbal response 3.1 min after the start of infusion, with 50% memory loss at 2.7 min. Children receiving propofol recognized 65 ± 16% of the pictures seen, whereas the control group recognized 93 ± 5%. Conclusion Measurement of memory and sedation is possible in verbal children receiving propofol by infusion in a clinical setting. Despite propofol being an amnestic agent, there was little or no amnestic effect of propofol while the child was verbally responsive. It is important for sedation providers to realize that propofol sedation does not always produce amnesia while the child is responsive. ClinicalTrials.gov number NCT02278003. PMID:27938911

Propofol sedation in children: sleep trumps amnesia.

Science.gov (United States)

Veselis, Robert; Kelhoffer, Eric; Mehta, Meghana; Root, James C; Robinson, Fay; Mason, Keira P

Detailed assessments of the effects of propofol on memory in children are lacking. We assessed the feasibility of measuring memory during propofol infusion, as commonly performed in sedation for MRI scanning. In addition, we determined the onset of memory loss in relation to the onset of sedation measured by verbal responsiveness. Children scheduled for sedation for MRI received a 10-min infusion of propofol (3 mg/kg) as they viewed and named 100 simple line drawings, one shown every five seconds, until they were no longer responsive (encoding). A control group receiving no sedation for MRI underwent similar tasks. Sedation was measured as any verbal response, regardless of correctness. After recovery from sedation, recognition memory was tested, with correct yes/no recognitions matched to sedation responses during encoding (subsequent memory paradigm). Of the 48 children who received propofol, 30 could complete all study tasks (6.2 ± 1.6 years, 16 males). Individual responses could be modeled in all 30 children. On average, there was a 50% probability of no verbal response 3.1 min after the start of infusion, with 50% memory loss at 2.7 min. Children receiving propofol recognized 65 ± 16% of the pictures seen, whereas the control group recognized 93 ± 5%. Measurement of memory and sedation is possible in verbal children receiving propofol by infusion in a clinical setting. Despite propofol being an amnestic agent, there was little or no amnestic effect of propofol while the child was verbally responsive. It is important for sedation providers to realize that propofol sedation does not always produce amnesia while the child is responsive. CLINICALTRIALS. NCT02278003. Copyright © 2016. Published by Elsevier B.V.

[Sedation with nitrous oxide in daily practice].

Science.gov (United States)

Martens, Luc C; Marks, Luc A

2003-01-01

Conscious sedation is recommended, together with behaviour management techniques, to facilitate treatment of dental fear or dental phobia patients. In this article the authors focus on inhalation sedation by means of nitrous oxide. The procedures and indications are explained and illustrated with clinical cases. On the strength of the literature and their own experience the authors reach the conclusion that Inhalation sedation is a kind of pharmacological behaviour management and an important additional tool to increase patient cooperation. Inhalation sedation can only be performed by trained practitioners under internationally accepted safety conditions. Inhalation sedation has a future in Belgium providing the appropriate law is adapted. This technique deserves a place in the dental curriculum.

Experimental study on the influence of oxygen content in the combustion air on the combustion characteristics

International Nuclear Information System (INIS)

Bělohradský, Petr; Skryja, Pavel; Hudák, Igor

2014-01-01

This study was focused on the experimental investigation of the very promising combustion technology called as the oxygen-enhanced combustion (OEC), which uses the oxidant containing higher proportion of oxygen than in the atmospheric air, i.e. more than 21%. The work investigated and compared the characteristics of two OEC methods, namely the premix enrichment and air-oxy/fuel combustion, when the overall oxygen concentration was varied from 21% to 46%. The combustion tests were performed with the experimental two-gas-staged burner of low-NO x type at the burner thermal input of 750 kW for two combustion regimes – one-staged and two-staged combustion. The oxygen concentration in the flue gas was maintained in the neighborhood of 3% vol. (on dry basis). The aim of tests was to assess the impact of the oxidant composition, type of OEC method and fuel-staging on the characteristic combustion parameters in detail. The investigated parameters included the concentration of nitrogen oxides (NO x ) in the flue gas, flue gas temperature, heat flux to the combustion chamber wall, and lastly the stability, shape and dimensions of flame. It was observed that NO x emission is significantly lower when the air-oxy/fuel method is used compared to the premix enrichment method. Moreover, when the fuel was staged, NO x emission was below 120 mg/Nm 3 at all investigated oxygen flow rates. Increasing oxygen concentration resulted in higher heating intensity due to higher concentrations of CO 2 and H 2 O. The available heat at 46% O 2 was higher by 20% compared with that at 21% O 2 . - Highlights: • Premix-enrichment and air-oxy/fuel combustion methods were experimentally studied. • NO x increased sharply as oxygen concentration increased during PE tests. • NO x was below 120 mg/Nm 3 for all investigated oxygen flow rates in AO tests. • Radiative heat transfer was enhanced ca. 20% as O 2 concentration was increased. • OEC flames were observed stable, more luminous and

Sedative effects of oral pregabalin premedication on intravenous sedation using propofol target-controlled infusion.

Science.gov (United States)

Karube, Noriko; Ito, Shinichi; Sako, Saori; Hirokawa, Jun; Yokoyama, Takeshi

2017-08-01

The sedative effects of pregabalin during perioperative period have not been sufficiently characterized. The aim of this study was to verify the sedative effects of premedication with pregabalin on intravenous sedation (IVS) using propofol and also to assess the influences of this agent on circulation, respiration, and postanesthetic complications. Ten healthy young volunteers underwent 1 h of IVS using propofol, three times per subject, on separate days (first time, no pregabalin; second time, pregabalin 100 mg; third time, pregabalin 200 mg). The target blood concentration (C T ) of propofol was increased in a stepwise fashion based on the bispectral index (BIS) value. Ramsay's sedation score (RSS) was determined at each propofol C T . Propofol C T was analyzed at each sedation level. Circulation and respiration during IVS and complications were also verified. Propofol C T was reduced at BIS values of 60 and 70 in both premedicated groups (100 mg: p = 0.043 and 0.041; 200 mg: p = 0.004 and 0.016, respectively) and at a BIS value of 80 in the pregabalin 200 mg group (p < 0.001). Propofol C T was decreased at RSS 4-6 in the pregabalin 100 mg group (RSS 4: p = 0.047; RSS 5: p = 0.007; RSS 6: p = 0.014), and at RSS 3-6 in the pregabalin 200 mg group (RSS 3-5: p < 0.001; RSS 6: p = 0.002). We conclude that oral premedication with pregabalin reduces the amount of propofol required to obtain an acceptable and adequate sedation level.

Buoyant Unstable Behavior of Initially Spherical Lean Hydrogen-Air Premixed Flames

Directory of Open Access Journals (Sweden)

Zuo-Yu Sun

2014-07-01

Full Text Available Buoyant unstable behavior in initially spherical lean hydrogen-air premixed flames within a center-ignited combustion vessel have been studied experimentally under a wide range of pressures (including reduced, normal, and elevated pressures. The experimental observations show that the flame front of lean hydrogen-air premixed flames will not give rise to the phenomenon of cellular instability when the equivalence ratio has been reduced to a certain value, which is totally different from the traditional understanding of the instability characteristics of lean hydrogen premixed flames. Accompanied by the smoothened flame front, the propagation mode of lean hydrogen premixed flames transitions from initially spherical outwardly towards upwardly when the flames expand to certain sizes. To quantitatively investigate such buoyant instability behaviors, two parameters, “float rate (ψ” and “critical flame radius (Rcr”, have been proposed in the present article. The quantitative results demonstrate that the influences of initial pressure (Pint on buoyant unstable behaviors are different. Based on the effects of variation of density difference and stretch rate on the flame front, the mechanism of such buoyant unstable behaviors has been explained by the competition between the stretch force and the results of gravity and buoyancy, and lean hydrogen premixed flames will display buoyant unstable behavior when the stretch effects on the flame front are weaker than the effects of gravity and buoyancy.

Palliative sedation in end-of-life care.

Science.gov (United States)

Maltoni, Marco; Scarpi, Emanuela; Nanni, Oriana

2013-07-01

The aim of this review was to present and comment on recent data published on palliative sedation in palliative and end-of-life care. Palliative sedation is a medical procedure used to deal with the refractory symptoms occurring in the advanced stages of cancer. It has clinical, nursing, relational and ethical implications, making it a highly sensitive issue. Over the last 12 months, a number of authors have published interesting new findings on different areas of palliative sedation, that is prevalence, indications, monitoring, duration and choice of drugs. In particular, a clear definition of palliative sedation and of its more pronounced form, deep continuous sedation (DCS), has emerged. It has been confirmed that, when performed in the correct way and with the right aims, palliative sedation does not have a detrimental impact on survival. Recent findings confirm that palliative sedation is an integral part of a medical palliative care approach and is needed in certain clinical situations. It is a legitimate clinical practice from any ethical point of view. While oncologists should have a basic knowledge of the procedure, its in depth study is a core competency for palliative care physicians.

Deep sedation during pneumatic reduction of intussusception.

Science.gov (United States)

Ilivitzki, Anat; Shtark, Luda Glozman; Arish, Karin; Engel, Ahuva

2012-05-01

Pneumatic reduction of intussusception under fluoroscopic guidance is a routine procedure. The unsedated child may resist the procedure, which may lengthen its duration and increase the radiation dose. We use deep sedation during the procedure to overcome these difficulties. The purpose of this study was to summarize our experience with deep sedation during fluoroscopic reduction of intussusception and assess the added value and complication rate of deep sedation. All children with intussusception who underwent pneumatic reduction in our hospital between January 2004 and June 2011 were included in this retrospective study. Anesthetists sedated the children using propofol. The fluoroscopic studies, ultrasound (US) studies and the childrens' charts were reviewed. One hundred thirty-one attempted reductions were performed in 119 children, of which 121 (92%) were successful and 10 (8%) failed. Two perforations (1.5%) occurred during attempted reduction. Average fluoroscopic time was 1.5 minutes. No complication to sedation was recorded. Deep sedation with propofol did not add any complication to the pneumatic reduction. The fluoroscopic time was short. The success rate of reduction was high,raising the possibility that sedation is beneficial, possibly by smooth muscle relaxation.

Propofol dose and incidence of dreaming during sedation.

Science.gov (United States)

Eer, Audrey Singyi; Padmanabhan, Usha; Leslie, Kate

2009-10-01

Dreaming is commonly reported after propofol-based sedation. We measured the incidence of dreaming and bispectral index (BIS) values in colonoscopy patients sedated with combinations of propofol, midazolam and fentanyl. Two hundred patients presenting for elective outpatient colonoscopy were sedated with combinations of propofol, midazolam and fentanyl. BIS was monitored throughout the procedure. Patients were interviewed immediately after they emerged from sedation. The primary end point was a report of dreaming during sedation. Ninety-seven patients were administered propofol alone, 44 were administered propofol and fentanyl, 16 were administered propofol and midazolam and 43 were administered propofol, midazolam and fentanyl. Dreaming was reported by 19% of patients. Dreamers received higher doses of propofol and had lower BIS values during sedation. Age of 50 years or less, preoperative quality of recovery score of less than 14, higher home dream recall, propofol dose of more than 300 mg and time to Observers' Assessment of Alertness/Sedation score equalling 5 of 8 min or less were independent predictors of dreaming. Dreaming during sedation is associated with higher propofol dose and lower BIS values.

Sedation-related complications in gastrointestinal endoscopy

OpenAIRE

Amornyotin, Somchai

2013-01-01

Sedation practices for gastrointestinal endoscopic (GIE) procedures vary widely in different countries depending on health system regulations and local circumstances. The goal of procedural sedation is the safe and effective control of pain and anxiety, as well as to provide an appropriate degree of memory loss or decreased awareness. Sedation-related complications in gastrointestinal endoscopy, once occurred, can lead to significant morbidity and occasional mortality in patients. The risk fa...

Sedation and monitoring for gastrointestinal endoscopy

OpenAIRE

Amornyotin, Somchai

2013-01-01

The safe sedation of patients for diagnostic or therapeutic procedures requires a combination of properly trained physicians and suitable facilities. Additionally, appropriate selection and preparation of patients, suitable sedative technique, application of drugs, adequate monitoring, and proper recovery of patients is essential. The goal of procedural sedation is the safe and effective control of pain and anxiety as well as to provide an appropriate degree of memory loss or decreased awaren...

21 CFR 170.60 - Nitrites and/or nitrates in curing premixes.

Science.gov (United States)

2010-04-01

... premixes, may continue to be used under prior sanctions in the commercial curing of meat and meat products... that apply to meat curing preparations for the home curing of meat and meat products, including poultry and wild game. To assure safe use of such ingredients the labeling of the premixes shall bear...

Premixing hydrogen burners for surface refinement of glass; Vormischende Wasserstoffbrenner zur Oberflaechenbearbeitung von Glas

Energy Technology Data Exchange (ETDEWEB)

Goerisch, Matthias [Linde AG, Linde Gas Deutschland, Nuernberg (Germany)

2013-02-15

As a result, inter alia, of unceasing globalisation, European glass producers in practically all sectors - flat glass, container glass, crystal glass and special glasses - are faced with ever tougher competition from Asia. In the 2012 to 2015 period and beyond, the principal focuses in the manufacture of glass products will again be on reducing overall production costs and increasing process efficiency wherever possible, on greater productivity and on enhanced product (surface) quality. To meet these challenges in the field of surface refinement and flame polishing of glass products as efficiently as possible, Linde AG/Linde Gases Division has developed premixing Hydropox {sup registered} burner technology for hydrogen/oxygen fuels. (orig.)

Subcutaneous dissociative conscious sedation (sDCS an alternative method for airway regional blocks: a new approach

Directory of Open Access Journals (Sweden)

Javid Mihan J

2011-10-01

Full Text Available Abstract Background Predicted difficult airway is a definite indication for awake intubation and spontaneous ventilation. Airway regional blocks which are commonly used to facilitate awake intubation are sometimes impossible or forbidden. On the other hand deep sedation could be life threatening in the case of compromised airway. The aim of this study is evaluating "Subcutaneous Dissociative Conscious Sedation" (sDCS as an alternative method to airway regional blocks for awake intubation. Methods In this prospective, non-randomized study, 30 patients with predicted difficult airway (laryngeal tumors, who were scheduled for direct laryngoscopic biopsy (DLB, underwent "Subcutaneous Dissociative Conscious Sedation" (sDCS exerted by intravenous fentanyl 3-4ug/kg and subcutaneous ketamine 0.6-0.7 mg/kg. The tongue and pharynx were anesthetized with lidocaine spray (4%. 10 minutes after a subcutaneous injection of ketamine direct laryngoscopy was performed. Extra doses of fentanyl 50-100 ug were administered if the patient wasn't cooperative enough for laryngoscopy. Patients were evaluated for hemodynamic stability (heart rate and blood pressure, oxygen saturation (Spo2, patient cooperation (obedient to open the mouth for laryngoscopy and the number of tries for laryngoscopy, patient comfort (remaining moveless, hallucination, nystagmus and salivation (need for aspiration before laryngoscopy. Results Direct laryngoscopy was performed successfully in all patients. One patient needed extra fentanyl and then laryngoscopy was performed successfully on the second try. All patients were cooperative enough during laryngoscopy. Hemodynamic changes more than 20% occurred in just one patient. Oxygen desaturation (spo2 Conclusions Subcutaneous Dissociative Conscious Sedation (sDCS as a new approach to airway is an acceptable and safe method for awake intubation and it can be suggested as a noninvasive substitute of low complication rate for regional airway

Pediatric dental sedation: challenges and opportunities

OpenAIRE

Nelson, Travis; Xu,Zheng

2015-01-01

Travis M Nelson, Zheng Xu Department of Pediatric Dentistry, University of Washington, Seattle, WA, USA Abstract: High levels of dental caries, challenging child behavior, and parent expectations support a need for sedation in pediatric dentistry. This paper reviews modern developments in pediatric sedation with a focus on implementing techniques to enhance success and patient safety. In recent years, sedation for dental procedures has been implicated in a disproportionate number of cases th...

Experimental study of the structure of rich premixed 1,3-butadiene/CH4/O2/Ar flame

OpenAIRE

Gueniche, Hadj-Ali; Glaude, Pierre-Alexandre; Fournet, René; Battin-Leclerc, Frédérique

2007-01-01

The structure of a laminar rich premixed 1,3-C4H6/CH4/O2/Ar flame have been investigated. 1,3-Butadiene, methane, oxygen and argon mole fractions are 0.033; 0.2073; 0.3315, and 0.4280, respectively, for an equivalent ratio of 1.80. The flame has been stabilized on a burner at a pressure of 6.7 kPa (50 Torr). The concentration profiles of stable species were measured by gas chromatography after sampling with a quartz probe. Quantified species included carbon monoxide and dioxide, methane, oxyg...

Comparison of sedation strategies for critically ill patients

DEFF Research Database (Denmark)

Hutton, Brian; Burry, Lisa D.; Kanji, Salmaan

2016-01-01

Background: Sedatives and analgesics are administered to provide sedation and manage agitation and pain in most critically ill mechanically ventilated patients. Various sedation administration strategies including protocolized sedation and daily sedation interruption are used to mitigate drug...... their efficacy and safety for mechanically ventilated patients. Methods: We will search the following from 1980 to March 2016: Ovid MEDLINE, CINAHL, Embase, PsycINFO, and Web of Science. We will also search the Cochrane Library, gray literature, and the International Clinical Trials Registry Platform. We...... of interest include duration of mechanical ventilation, time to first extubation, ICU and hospital length of stay, re-intubation, tracheostomy, mortality, total sedative and opioid exposure, health-related quality of life, and adverse events. To inform our NMA, we will first conduct conventional pair...

The use of observational scales to monitor symptom control and depth of sedation in patients requiring palliative sedation: a systematic review.

Science.gov (United States)

Brinkkemper, Tijn; van Norel, Arjanne M; Szadek, Karolina M; Loer, Stephan A; Zuurmond, Wouter W A; Perez, Roberto S G M

2013-01-01

Palliative sedation is the intentional lowering of consciousness of a patient in the last phase of life to relieve suffering from refractory symptoms such as pain, delirium and dyspnoea. In this systematic review, we evaluated the use of monitoring scales to assess the degree of control of refractory symptoms and/or the depth of the sedation. A database search of PubMed and Embase was performed up to January 2010 using the search terms 'palliative sedation' OR 'terminal sedation'. Retro- and prospective studies as well as reviews and guidelines containing information about monitoring of palliative sedation, written in the English, German or Dutch language were included. The search yielded 264 articles of which 30 were considered relevant. Most studies focused on monitoring refractory symptoms (pain, fatigue or delirium) or the level of awareness to control the level of sedation. Four prospective and one retrospective study used scales validated in other settings: the Numeric Pain Rating Scale, the Visual Analogue Scale, the Memorial Delirium Assessment Scale, the Communication Capacity Scale and Agitation Distress Scale. Only the Community Capacity Scale was partially validated for use in a palliative sedation setting. One guideline described the use of a scale validated in another setting. A minority of studies reported the use of observational scales to monitor the effect of palliative sedation. Future studies should be focused on establishing proper instruments, most adequate frequency and timing of assessment, and interdisciplinary evaluation of sedation depth and symptom control for palliative sedation.

Effects of premixed diethyl ether (DEE) on combustion and exhaust emissions in a HCCI-DI diesel engine

International Nuclear Information System (INIS)

Cinar, Can; Can, Ozer; Sahin, Fatih; Yucesu, H. Serdar

2010-01-01

In this study, the effects of premixed ratio of diethyl ether (DEE) on the combustion and exhaust emissions of a single-cylinder, HCCI-DI engine were investigated. The experiments were performed at the engine speed of 2200 rpm and 19 N m operating conditions. The amount of the premixed DEE was controlled by a programmable electronic control unit (ECU) and the DEE injection was conducted into the intake air charge using low pressure injector. The premixed fuel ratio (PFR) of DEE was changed from 0% to 40% and results were compared to neat diesel operation. The percentages of premixed fuel were calculated from the energy ratio of premixed DEE fuel to total energy rate of the fuels. The experimental results show that single stage ignition was found with the addition of premixed DEE fuel. Increasing and phasing in-cylinder pressure and heat release were observed in the premixed stage of the combustion. Lower diffusion combustion was also occurred. Cycle-to cycle variations were very small with diesel fuel and 10% DEE premixed fuel ratio. Audible knocking occurred with 40% DEE premixed fuel ratio. NO x -soot trade-off characteristics were changed and improvements were found simultaneously. NO x and soot emissions decreased up to 19.4% and 76.1%, respectively, while exhaust gas temperature decreased by 23.8%. On the other hand, CO and HC emissions increased.

Optimizing oxygenation and intubation conditions during awake fibre-optic intubation using a high-flow nasal oxygen-delivery system.

Science.gov (United States)

Badiger, S; John, M; Fearnley, R A; Ahmad, I

2015-10-01

Awake fibre-optic intubation is a widely practised technique for anticipated difficult airway management. Despite the administration of supplemental oxygen during the procedure, patients are still at risk of hypoxia because of the effects of sedation, local anaesthesia, procedural complications, and the presence of co-morbidities. Traditionally used oxygen-delivery devices are low flow, and most do not have a sufficient reservoir or allow adequate fresh gas flow to meet the patient's peak inspiratory flow rate, nor provide an adequate fractional inspired oxygen concentration to prevent desaturation should complications arise. A prospective observational study was conducted using a high-flow humidified transnasal oxygen-delivery system during awake fibre-optic intubation in 50 patients with anticipated difficult airways. There were no episodes of desaturation or hypercapnia using the high-flow system, and in all patients the oxygen saturation improved above baseline values, despite one instance of apnoea resulting from over-sedation. All patients reported a comfortable experience using the device. The high-flow nasal oxygen-delivery system improves oxygenation saturation, decreases the risk of desaturation during the procedure, and potentially, optimizes conditions for awake fibre-optic intubation. The soft nasal cannulae uniquely allow continuous oxygenation and simultaneous passage of the fibrescope and tracheal tube. The safety of the procedure may be increased, because any obstruction, hypoventilation, or periods of apnoea that may arise may be tolerated for longer, allowing more time to achieve ventilation in an optimally oxygenated patient. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Effect of air-excess on blends of RON70 partially premixed combustion

NARCIS (Netherlands)

Wang, S.; Bakker, P.C.; Somers, L.M.T.; de Goey, L.P.H.

Partially Premixed Combustion (PPC) is a combustion concept that aims to provide combustion with low smoke and NOx emissions and a high thermal efficiency. Extending the ignition delay to enhance premixing, avoiding spray-driven combustion, and controlling temperature at an optimum level through use

A comparative experimental study on engine operating on premixed charge compression ignition and compression ignition mode

Directory of Open Access Journals (Sweden)

Bhiogade Girish E.

2017-01-01

Full Text Available New combustion concepts have been recently developed with the purpose to tackle the problem of high emissions level of traditional direct injection Diesel engines. A good example is the premixed charge compression ignition combustion. A strategy in which early injection is used causing a burning process in which the fuel burns in the premixed condition. In compression ignition engines, soot (particulate matter and NOx emissions are an extremely unsolved issue. Premixed charge compression ignition is one of the most promising solutions that combine the advantages of both spark ignition and compression ignition combustion modes. It gives thermal efficiency close to the compression ignition engines and resolves the associated issues of high NOx and particulate matter, simultaneously. Premixing of air and fuel preparation is the challenging part to achieve premixed charge compression ignition combustion. In the present experimental study a diesel vaporizer is used to achieve premixed charge compression ignition combustion. A vaporized diesel fuel was mixed with the air to form premixed charge and inducted into the cylinder during the intake stroke. Low diesel volatility remains the main obstacle in preparing premixed air-fuel mixture. Exhaust gas re-circulation can be used to control the rate of heat release. The objective of this study is to reduce exhaust emission levels with maintaining thermal efficiency close to compression ignition engine.

Safe sedation in general practice

African Journals Online (AJOL)

anxiolysis, amnesia, sedation or pain control? ∙ What will the effect of the drugs be on the airway, spontaneous breathing and cardiovascular system? The patient. As more procedures are performed OOR, the operator has retained the opportunity to evaluate patients pre-operatively. However, the sedation provider usually ...

Clonidine Sedation Effects in Children During Electroencephalography

Directory of Open Access Journals (Sweden)

Mohammad Barzegar

2017-10-01

Full Text Available It is very important to have proper management in children with Seizure. Electroencephalography (EEG as a diagnostic instrument has a key role in determining the management method of seizure in children. Because of poor cooperation of some children (especially children with attention deficit hyperactivity disorders and developmental disorders in performing EEG, it is the best choice to sedate children before EEG. The aim of present study is to evaluate the sedation efficacy of clonidine in children before EEG. In a randomized clinical trial, 45 children age 2 to 12 with seizure, who referred to Children Hospital of Tabriz University of Medical Sciences and candidate for EEG, were studied. Sedation before EEG induced by 0.5 to 2.0 mg clonidine orally. Sedation score (0 to 5 measured by using eyes condition, response to voice, and response to touch. Successful sedation, EEG performing, and hemodynamic stability were evaluated during sedation. Of all patients, 40 patients (88.88% were sedated successfully, and EEG was performed for all of the children. Mean onset time of clonidine effect was 35.47±13.56 minutes and mean time of that the patients’ level of consciousness back to the level before administrating of clonidine was 77.55±26.87 minutes. Hemodynamic states of all patients were stable during the study, and there were no significant changes in vital sign of patients. In conclusion, clonidine can be considered as a safe alternative medication for sedation for EEG, which is fortunately associated with no significant change in vital signs, which may complicate overall status of patients.

"Sedation is tricky": A qualitative content analysis of nurses' perceptions of sedation administration in mechanically ventilated intensive care unit patients.

Science.gov (United States)

Hetland, Breanna; Guttormson, Jill; Tracy, Mary Fran; Chlan, Linda

2018-03-20

Critical care nurses are responsible for administering sedative medications to mechanically ventilated patients. With significant advancements in the understanding of the impact of sedative exposure on physiological and psychological outcomes of ventilated patients, updated practice guidelines for assessment and management of pain, agitation, and delirium in the intensive care unit were released in 2013. The primary aim of this qualitative study was to identify and describe themes derived from critical care nurses' comments regarding sedation administration practices with mechanically ventilated patients. This is a qualitative content analysis of secondary text data captured through a national electronic survey of members of the American Association of Critical-Care Nurses. A subsample (n = 67) of nurses responded to a single, open-ended item at the end of a survey that evaluated nurses' perceptions of current sedation administration practices. Multiple factors guided sedation administration practices, including individual patient needs, nurses' synthesis of clinical evidence, application of best practices, and various personal and professional practice perspectives. Our results also indicated nurses desire additional resources to improve their sedation administration practices including more training, better communication tools, and adequate staffing. Critical care nurses endorse recommendations to minimise sedation administration when possible, but a variety of factors, including personal perspectives, impact sedation administration in the intensive care unit and need to be considered. Critical care nurses continue to encounter numerous challenges when assessing and managing sedation of mechanically ventilated patients. Copyright © 2018 Australian College of Critical Care Nurses Ltd. Published by Elsevier Ltd. All rights reserved.

Advanced paediatric conscious sedation: an alternative to dental general anaesthetic in the U.K.

Science.gov (United States)

Hand, Darren; Averley, Paul; Lyne, John; Girdler, Nick

2011-01-01

Child dental anxiety is widespread, and it is not always possible to treat children using traditional methods such as behavioural management, local anaesthesia and even relative analgesia. In such cases a dental general anaesthetic (DGA) is the only option available to facilitate dental treatment in anxious children. This study describes an advanced conscious sedation protocol which allows invasive treatment to be carried out in anxious children. It incorporates the use of titrated intravenous midazolam and fentanyl and inhalation agents, sevoflurane and nitrous oxide/oxygen, which is administered by a Consultant Anaesthetist. The aim is to produce an evidence- based study which can offer a sedation technique as a safe and effective alternative to a DGA. Retrospective audit. 267 clinical records were audited retrospectively from a specialist sedation-based clinic, for children aged 5-15 years old. The subjects all underwent invasive dental procedures with this technique between August and November 2008 as an alternative to a DGA. 262/267 (98%) of the subjects were treated safely and successfully and without the loss of verbal communication using this technique. This included many treatments requiring four quadrant dentistry, with both restorations and extractions as necessary being carried out in one visit. 5 subjects (2%) did not tolerate treatment and had to be referred for a DGA. No medical emergencies occurred. Based on the evidence for this group of patients, this advanced conscious sedation technique, offers a safe and effective alternative to DGA. This technique must be carried out in an appropriate environment by an appropriately trained and experienced team who are able to comply with the recommendations for "alternative" sedation techniques.

Pediatric neuro MRI. Tricks to minimize sedation

Energy Technology Data Exchange (ETDEWEB)

Barkovich, Matthew J.; Desikan, Rahul S. [University of California, San Francisco, Department of Radiology and Diagnostic Imaging, San Francisco, CA (United States); Xu, Duan; Barkovich, A.J. [University of California, San Francisco, Department of Radiology and Diagnostic Imaging, San Francisco, CA (United States); UCSF-Benioff Children' s Hospital, Department of Radiology, San Francisco, CA (United States); Williams, Cassandra [UCSF-Benioff Children' s Hospital, Department of Radiology, San Francisco, CA (United States)

2018-01-15

Magnetic resonance imaging (MRI) is the workhorse modality in pediatric neuroimaging because it provides excellent soft-tissue contrast without ionizing radiation. Until recently, studies were uninterpretable without sedation; however, given development of shorter sequences, sequences that correct for motion, and studies showing the potentially deleterious effects of sedation on immature laboratory animals, it is prudent to minimize sedation when possible. This manuscript provides basic guidelines for performing pediatric neuro MRI without sedation by both modifying technical factors to reduce scan time and noise, and using a multi-disciplinary team to coordinate imaging with the patient's biorhythms. (orig.)

Sedation practice in Nordic and non-Nordic ICUs

DEFF Research Database (Denmark)

Egerod, Ingrid; Albarran, John W; Ring, Mette

2013-01-01

A trend towards lighter sedation has been evident in many intensive care units (ICUs). The aims of the survey were to describe sedation practice in European ICUs and to compare sedation practice in Nordic and non-Nordic countries....

Moderate sedation for MRI in young children with autism

Energy Technology Data Exchange (ETDEWEB)

Ross, Allison Kinder [Duke University Medical Center, Division of Pediatric Anesthesia, Durham (United States); Hazlett, Heather Cody; Garrett, Nancy T [University of North Carolina School of Medicine, Department of Psychiatry, Chapel Hill, NC (United States); Wilkerson, Christy [Duke University Medical Center, Department of Radiology, Durham, NC (United States); Piven, Joseph [University of North Carolina School of Medicine, Departments of Psychiatry and Pediatrics, Chapel Hill, NC (United States)

2005-09-01

Autism is a pervasive neurodevelopmental disorder. Because of the deficits associated with the condition, sedation of children with autism has been considered more challenging than sedation of other children. To test this hypothesis, we compared children with autism against clinical controls to determine differences in requirements for moderate sedation for MRI. Children ages 18-36 months with autism (group 1, n = 41) and children with no autistic behavior (group 2, n = 42) were sedated with a combination of pentobarbital and fentanyl per sedation service protocol. The sedation nurse was consistent for all patients, and all were sedated to achieve a Modified Ramsay Score of 4. Demographics and doses of sedatives were recorded and compared. There were no sedation failures in either group. Children in group 1 (autism) were significantly older than group 2 (32.02{+-}3.6 months vs 28.16{+-}6.7 months) and weighed significantly more (14.87{+-}2.1 kg vs 13.42{+-}2.2 kg). When compared on a per-kilogram basis, however, group 1 had a significantly lower fentanyl requirement than group 2 (1.25{+-}0.55 mcg/kg vs 1.57{+-}0.81 mcg/kg), but no significant difference was found in pentobarbital dosing between groups 1 and 2, respectively (4.92{+-}0.92 mg/kg vs 5.21{+-}1.6 mg/kg). Autistic children in this age range are not more difficult to sedate and do not require higher doses of sedative agents for noninvasive imaging studies. (orig.)

Computational aspects of premixing modelling

Energy Technology Data Exchange (ETDEWEB)

Fletcher, D.F. [Sydney Univ., NSW (Australia). Dept. of Chemical Engineering; Witt, P.J.

1998-01-01

In the steam explosion research field there is currently considerable effort being devoted to the modelling of premixing. Practically all models are based on the multiphase flow equations which treat the mixture as an interpenetrating continuum. Solution of these equations is non-trivial and a wide range of solution procedures are in use. This paper addresses some numerical aspects of this problem. In particular, we examine the effect of the differencing scheme for the convective terms and show that use of hybrid differencing can cause qualitatively wrong solutions in some situations. Calculations are performed for the Oxford tests, the BNL tests, a MAGICO test and to investigate various sensitivities of the solution. In addition, we show that use of a staggered grid can result in a significant error which leads to poor predictions of `melt` front motion. A correction is given which leads to excellent convergence to the analytic solution. Finally, we discuss the issues facing premixing model developers and highlight the fact that model validation is hampered more by the complexity of the process than by numerical issues. (author)

Response of partially premixed flames to acoustic velocity and equivalence ratio perturbations

Energy Technology Data Exchange (ETDEWEB)

Kim, K.T.; Lee, J.G.; Quay, B.D.; Santavicca, D.A. [Center for Advanced Power Generation, Department of Mechanical and Nuclear Engineering, The Pennsylvania State University, University Park, PA (United States)

2010-09-15

This article describes an experimental investigation of the forced response of a swirl-stabilized partially premixed flame when it is subjected to acoustic velocity and equivalence ratio fluctuations. The flame's response is analyzed using phase-resolved CH{sup *} chemiluminescence images and flame transfer function (FTF) measurements, and compared with the response of a perfectly premixed flame under acoustic perturbations. The nonlinear response of the partially premixed flame is manifested by a partial extinction of the reaction zone, leading to rapid reduction of flame surface area. This nonlinearity, however, is observed only when the phase difference between the acoustic velocity and the equivalence ratio at the combustor inlet is close to zero. The condition, {delta}{phi}{sub {phi}}'-V'{approx}0 , indicates that reactant mixtures with high equivalence ratio impinge on the flame front with high velocity, inducing large fluctuations of the rate of heat release. It is found that the phase difference between the acoustic velocity and equivalence ratio nonuniformities is a key parameter governing the linear/nonlinear response of a partially premixed flame, and it is a function of modulation frequency, inlet velocity, fuel injection location, and fuel injector impedance. The results presented in this article will provide insight into the response of a partially premixed flame, which has not been well explored to date. (author)

A Review of Agents for Palliative Sedation/Continuous Deep Sedation: Pharmacology and Practical Applications.

Science.gov (United States)

Bodnar, John

2017-03-01

Continuous deep sedation at the end of life is a specific form of palliative sedation requiring a care plan that essentially places and maintains the patient in an unresponsive state because their symptoms are refractory to any other interventions. Because this application is uncommon, many providers may lack practical experience in this specialized area and resources they can access are outdated, nonspecific, and/or not comprehensive. The purpose of this review is to provide an evidence- and experience-based reference that specifically addresses those medications and regimens and their practical applications for this very narrow, but vital, aspect of hospice care. Patient goals in a hospital and hospice environments are different, so the manner in which widely used sedatives are dosed and applied can differ greatly as well. Parameters applied in end-of-life care that are based on experience and a thorough understanding of the pharmacology of those medications will differ from those applied in an intensive care unit or other medical environments. By recognizing these different goals and applying well-founded regimens geared specifically for end-of-life sedation, we can address our patients' symptoms in a more timely and efficacious manner.

Comparison Between Premixed and Compounded Parenteral Nutrition Solutions in Hospitalized Patients Requiring Parenteral Nutrition.

Science.gov (United States)

Beattie, Colleen; Allard, Johane; Raman, Maitreyi

2016-04-01

Parenteral nutrition (PN) may be provided through compounded or premixed solutions. To determine the proportion of stable custom-compounded PN prescriptions that would fit within a 20% deviance of an existing premixed PN solution. A retrospective study design was used. Inpatients who received PN in non-critical care units in the preceding year were screened for eligibility. Results are reported descriptively as means (95% confidence intervals) and proportions. We reviewed 97 PN prescriptions that met inclusion criteria. Stable hospital PN prescriptions compared with the reference premixed prescription provided 1838 (1777-1898) vs 1843 (1781-1905) kcal/d, P = .43; dextrose, 266 (254-277) vs 225 (216-234) g/d, P magnesium, 5.4 (4.8-5.4) vs 7.6 (7.4-7.9) mmol/L. Calories and protein were remarkably similar, but dextrose, lipid, and electrolytes differed between hospital PN and the reference premixed prescription. We believe that there may be a role for premixed solutions in quaternary centers in stable non-critically ill patients. © 2016 American Society for Parenteral and Enteral Nutrition.

Moderate sedation for MRI in young children with autism

International Nuclear Information System (INIS)

Ross, Allison Kinder; Hazlett, Heather Cody; Garrett, Nancy T.; Wilkerson, Christy; Piven, Joseph

2005-01-01

Autism is a pervasive neurodevelopmental disorder. Because of the deficits associated with the condition, sedation of children with autism has been considered more challenging than sedation of other children. To test this hypothesis, we compared children with autism against clinical controls to determine differences in requirements for moderate sedation for MRI. Children ages 18-36 months with autism (group 1, n = 41) and children with no autistic behavior (group 2, n = 42) were sedated with a combination of pentobarbital and fentanyl per sedation service protocol. The sedation nurse was consistent for all patients, and all were sedated to achieve a Modified Ramsay Score of 4. Demographics and doses of sedatives were recorded and compared. There were no sedation failures in either group. Children in group 1 (autism) were significantly older than group 2 (32.02±3.6 months vs 28.16±6.7 months) and weighed significantly more (14.87±2.1 kg vs 13.42±2.2 kg). When compared on a per-kilogram basis, however, group 1 had a significantly lower fentanyl requirement than group 2 (1.25±0.55 mcg/kg vs 1.57±0.81 mcg/kg), but no significant difference was found in pentobarbital dosing between groups 1 and 2, respectively (4.92±0.92 mg/kg vs 5.21±1.6 mg/kg). Autistic children in this age range are not more difficult to sedate and do not require higher doses of sedative agents for noninvasive imaging studies. (orig.)

Impact of office-based intravenous deep sedation providers upon traditional sedation practices employed in pediatric dentistry.

Science.gov (United States)

Tarver, Michael; Guelmann, Marcio; Primosch, Robert

2012-01-01

This survey intended to determine how the implementation of office-based IV deep sedation by a third party provider (OIVSED) impacted the traditional sedation practices employed in pediatric dentistry private practice settings. A digital survey was e-mailed to 924 members of the American Academy of Pediatric Dentistry practicing in California, Florida, and New York, chosen because these states had large samples of practicing pediatric dentists in geographically disparate locations. 151 pediatric dentists using OIVSED responded to the survey. Improved efficiency, safety and quality of care provided, and increased parental acceptance were reported advantages of this service. Although less costly than hospital-based general anesthesia, the average fee for this service was a deterrent to some parents considering this option. Sixty-four percent of respondents continued to provide traditional sedation modalities, mostly oral sedation, in their offices, as parenteral routes taught in their training programs were less often selected. OIVSED users reported both a reduction in the use of traditional sedation modalities in their offices and use of hospital-based GA services in exchange for perceived improvements in efficiency, safety and quality of care delivered. Patient costs, in the absence of available health insurance coverage, inhibited accessing this service by some parents.

Sedative and cardiorespiratory effects of detomidine constant rate infusion in sheep.

Science.gov (United States)

de Moura, Rauane Sousa; Bittar, Isabela Plazza; da Silva, Luiz Henrique; Villela, Ana Carolina Vasquez; Dos Santos Júnior, Marcelo Borges; Borges, Naida Cristina; Franco, Leandro Guimarães

2018-02-01

The use of sheep in experiments is widespread and is increasing worldwide, and so is the need to develop species-specific anaesthetic techniques to ensure animal safety. Previous studies have mentioned several protocols involving the administration of alpha-2 adrenergic agonists in sheep; however, assessment of the efficacy and safety of these infusion techniques is still relatively new. Thus, the aim of the present study is to assess the effectiveness of detomidine constant rate infusion (CRI) in sheep by measuring the cardiovascular and respiratory parameters, blood gas variables and sedation scores. Eight adult female Santa Inês sheep received 20 µg/kg of detomidine hydrochloride intravenously as a bolus loading dose, followed by an infusion rate of 60 µg/kg/h. The heart rates and respiratory rates changed continuously during the CRI period. No arrhythmias were observed. The reduction in arterial partial pressure of oxygen (PaO 2 ) was not significant, but one animal showed signs of hypoxaemia (minimum PaO 2 of 66.9 mmHg). The arterial partial pressure of carbon dioxide (PaCO 2 ) increased, but the animals did not become hypercapnic. The bicarbonate (HCO 3- ), pH and base excess (BE) tended towards metabolic alkalosis. The cardiac output (CO), stroke volume (SV), cardiac index (CI) and ejection fraction (EF%) showed no significant changes. The fractional shortening (FS%) decreased slightly, starting at T 45min . Sedation scores varied between 3 (0/10) after sedation and during recovery and 7 (0/10) during CRI. We concluded that administering detomidine at an infusion rate of 60 µg/kg/h in Santa Inês sheep is a simple technique that produces satisfactory sedation for minimally invasive procedures.

Atelectasis on pediatric chest CT: comparison of sedation techniques

International Nuclear Information System (INIS)

Sargent, M.A.; McEachern, A.M.; Jamieson, D.H.

1999-01-01

Background. A change in practice at our institution resulted in increased use of anesthesia for CT scan of the chest in children who required sedation. Objective. To determine whether there is a difference in the frequency or severity of pulmonary atelectasis on CT scan in children sedated by anesthesiologists compared with children sedated by radiologists using intravenous pentobarbital. Materials and methods. Retrospective blinded review of 60 CT scans of the chest performed in 41 children. Forty-one studies in children sedated by radiologists (median age 29 months) were compared with 19 studies in children sedated by anesthesiologists (median age 25 months). Results. Atelectasis sufficient to obscure pulmonary metastases was shown in 5 of 41 (12 %) radiology sedations and 13 of 19 (68 %) anesthesiology sedations (P < 0.01). Higher grades of atelectasis were recorded in children under anesthesia (P < 0.01). Conclusion. Atelectasis is more frequent and more severe in children undergoing general anesthesia compared with intravenous pentobarbital sedation. Consideration should be given to the use of forced inspiration in children anesthetized for CT scan of the chest. (orig.)

Ketamine-propofol sedation in circumcision

Directory of Open Access Journals (Sweden)

Handan Gulec

2015-10-01

Full Text Available ABSTRACTBACKGROUND AND OBJECTIVE: To compare the therapeutic effects of ketamine alone or ketamine plus propofol on analgesia, sedation, recovery time, side effects in premedicated children with midazolam-ketamine-atropin who are prepared circumcision operation.METHODS: 60 American Society of Anaesthesiologists physical status I-II children, aged between 3 and 9 years, undergoing circumcision operations under sedation were recruited according to a randomize and double-blind institutional review board-approved protocol. Patients were randomized into two groups via sealed envelope assignment. Both groups were administered a mixture of midazolam 0.05 mg/kg + ketamine 3 mg/kg + atropine 0.02 mg/kg intramuscularly in the presence of parents in the pre-operative holding area. Patients were induced with propofol-ketamine in Group I or ketamine alone in Group II.RESULTS: In the between-group comparisons, age, weight, initial systolic blood pressure, a difference in terms of the initial pulse rate was observed (p > 0.050. Initial diastolic blood pressure and subsequent serial measurements of 5, 10, 15, 20th min, systolic blood pressure, diastolic blood pressure and pulse rate in ketamine group were significantly higher (p < 0.050.CONCLUSION: Propofol-ketamine (Ketofol provided better sedation quality and hemodynamy than ketamine alone in pediatric circumcision operations. We did not observe significant complications during sedation in these two groups. Therefore, ketofol appears to be an effective and safe sedation method for circumcision operation.

[Comparison of two methods for conscious sedation in maxillofacial surgery with local anesthesia].

Science.gov (United States)

Zöller, J; Zöller, B; Hassfeld, S; Köhler, J

1992-01-01

A randomised, prospective study was conducted to compare the efficiency and safety of methods for intravenous conscious sedation in patients undergoing oral surgery under local analgesia. 150 systemically healthy patients (ASA Class I and II) participated. Three groups were formed: group 1 received 0.05 mg/kg midazolam; group 2 0.05 mg/kg midazolam, 1.5 mg/kg tramadol, 50 mg alizaprid; group 3 0.05 mg/kg midazolam, 0.2 mg/kg nalbuphine, 50 mg alizaprid. Blood pressure, heart rate and oxygen saturation were measured throughout the procedure. The results confirmed that the use of nalbuphine (group 3) allows a reduction in the mean dosage of midazolam required to produce satisfactory sedation and effected a more rapid recovery time compared to group 12 and 2. With the combination nalbuphine and alizaprid nausea and vomiting could be reduced for the most part compared to group 2.

[AWAKE CRANIOTOMY: IN SEARCH FOR OPTIMAL SEDATION].

Science.gov (United States)

Kulikova, A S; Sel'kov, D A; Kobyakov, G L; Shmigel'skiy, A V; Lubnin, A Yu

2015-01-01

Awake craniotomy is a "gold standard"for intraoperative brain language mapping. One of the main anesthetic challenge of awake craniotomy is providing of optimal sedation for initial stages of intervention. The goal of this study was comparison of different technics of anesthesia for awake craniotomy. Materials and methods: 162 operations were divided in 4 groups: 76 cases with propofol sedation (2-4mg/kg/h) without airway protection; 11 cases with propofol sedation (4-5 mg/kg/h) with MV via LMA; 36 cases of xenon anesthesia; and 39 cases with dexmedetomidine sedation without airway protection. Results and discussion: brain language mapping was successful in 90% of cases. There was no difference between groups in successfulness of brain mapping. However in the first group respiratory complications were more frequent. Three other technics were more safer Xenon anesthesia was associated with ultrafast awakening for mapping (5±1 min). Dexmedetomidine sedation provided high hemodynamic and respiratory stability during the procedure.

Chloral hydrate in pediatric magnetic resonance imaging: evaluation of a 10-year sedation experience administered by radiologists

International Nuclear Information System (INIS)

Delgado, Jorge; Toro, Rodrigo; Rascovsky, Simon; Arango, Andres; Angel, Gabriel J.; Calvo, Victor; Delgado, Jorge A.

2015-01-01

Chloral hydrate is a sedative that has been used for magnetic resonance imaging (MRI). To evaluate the use, effectiveness and safety of chloral hydrate administered by radiologists for the sedation of children who require MRI procedures. We retrospectively reviewed the clinical charts for all patients ages 0 - 10 years old who underwent sedation with chloral hydrate for MRI from January 2000 to December 2010. Demographic factors, dose information, indication for MRI, therapeutic failures and adverse reactions to the drug were reviewed. One thousand, seven hundred and three children (946 males, 757 females) with a median age of 2.5 years (range: 4 days - 9.91 years) received chloral hydrate. Moderate to deep sedation was achieved in 1,618/1,703 (95%) of the patients, 35/1,703 (2.1%) of the patients failed to achieve moderate to deep sedation, and 47/1,703 (2.8%) of the patients woke up during MRI examination. Adverse reactions were present in 31/1,703 (1.8%) of the patients. Three severe adverse reactions occurred (0.18%). A single dose of chloral hydrate (40-60 mg/kg) was administered to 1,477/1,703 patients (86.7%). An additional dose of chloral hydrate (10-20 mg/kg), given 15 min after the first dose or when the patient woke up during the MRI examination, was required in 226/1,703 patients (13.3%). The likelihood of requiring an additional dose in children older than 2 years was 2.2 times the likelihood compared to children younger than 2 years (OR = 2.2 [95%CI: 1.6-3.0]). The use of a reduced dose (<50 mg/kg) was not associated with a higher therapeutic failure rate (OR = 1.04 [95%CI 0.57-1.89]). Chloral hydrate is an appropriate sedation option for pediatric patients in MRI services when strict patient selection criteria are met. The use of a reduced dose does not affect the effectiveness of sedation. The lack of data regarding the presence of transient oxygen desaturation, the time to induce sedation and the exact duration of sedation are limitations of this

Chloral hydrate in pediatric magnetic resonance imaging: evaluation of a 10-year sedation experience administered by radiologists

Energy Technology Data Exchange (ETDEWEB)

Delgado, Jorge; Toro, Rodrigo; Rascovsky, Simon; Arango, Andres; Angel, Gabriel J.; Calvo, Victor; Delgado, Jorge A. [Fundacion Instituto de Alta Tecnologia Medica, Department of Radiology, Medellin (Colombia)

2014-08-21

Chloral hydrate is a sedative that has been used for magnetic resonance imaging (MRI). To evaluate the use, effectiveness and safety of chloral hydrate administered by radiologists for the sedation of children who require MRI procedures. We retrospectively reviewed the clinical charts for all patients ages 0 - 10 years old who underwent sedation with chloral hydrate for MRI from January 2000 to December 2010. Demographic factors, dose information, indication for MRI, therapeutic failures and adverse reactions to the drug were reviewed. One thousand, seven hundred and three children (946 males, 757 females) with a median age of 2.5 years (range: 4 days - 9.91 years) received chloral hydrate. Moderate to deep sedation was achieved in 1,618/1,703 (95%) of the patients, 35/1,703 (2.1%) of the patients failed to achieve moderate to deep sedation, and 47/1,703 (2.8%) of the patients woke up during MRI examination. Adverse reactions were present in 31/1,703 (1.8%) of the patients. Three severe adverse reactions occurred (0.18%). A single dose of chloral hydrate (40-60 mg/kg) was administered to 1,477/1,703 patients (86.7%). An additional dose of chloral hydrate (10-20 mg/kg), given 15 min after the first dose or when the patient woke up during the MRI examination, was required in 226/1,703 patients (13.3%). The likelihood of requiring an additional dose in children older than 2 years was 2.2 times the likelihood compared to children younger than 2 years (OR = 2.2 [95%CI: 1.6-3.0]). The use of a reduced dose (<50 mg/kg) was not associated with a higher therapeutic failure rate (OR = 1.04 [95%CI 0.57-1.89]). Chloral hydrate is an appropriate sedation option for pediatric patients in MRI services when strict patient selection criteria are met. The use of a reduced dose does not affect the effectiveness of sedation. The lack of data regarding the presence of transient oxygen desaturation, the time to induce sedation and the exact duration of sedation are limitations of this

Large eddy simulation of turbulent premixed combustion flows over backward facing step

Energy Technology Data Exchange (ETDEWEB)

Park, Nam Seob [Yuhan University, Bucheon (Korea, Republic of); Ko, Sang Cheol [Jeju National University, Jeju (Korea, Republic of)

2011-03-15

Large eddy simulation (LES) of turbulent premixed combustion flows over backward facing step has been performed using a dynamic sub-grid G-equation flamelet model. A flamelet model for the premixed flame is combined with a dynamic sub-grid combustion model for the filtered propagation of flame speed. The objective of this study is to investigate the validity of the dynamic sub-grid G-equation model in a complex turbulent premixed combustion flow. For the purpose of validating the LES combustion model, the LES of isothermal and reacting shear layer formed at a backward facing step is carried out. The calculated results are compared with the experimental results, and a good agreement is obtained.

Large eddy simulation of turbulent premixed combustion flows over backward facing step

International Nuclear Information System (INIS)

Park, Nam Seob; Ko, Sang Cheol

2011-01-01

Large eddy simulation (LES) of turbulent premixed combustion flows over backward facing step has been performed using a dynamic sub-grid G-equation flamelet model. A flamelet model for the premixed flame is combined with a dynamic sub-grid combustion model for the filtered propagation of flame speed. The objective of this study is to investigate the validity of the dynamic sub-grid G-equation model in a complex turbulent premixed combustion flow. For the purpose of validating the LES combustion model, the LES of isothermal and reacting shear layer formed at a backward facing step is carried out. The calculated results are compared with the experimental results, and a good agreement is obtained

Gasoline – ignition improver – oxygenate blends as fuels for advanced compression ignition combustion

NARCIS (Netherlands)

Zhou, L.; Boot, M.D.; Goey, de L.P.H.

2013-01-01

Mixing is inhibited both by the relatively low volatility of conventional diesel fuel and the short premixing time due to high fuel reactivity (i.e. cetane number (CN)). Consequently, in this research two promising oxygenates which can be produced from 2 nd generation biomass -ethanol from cellulose

SEDATIVE AND ANALGESIC EFFECTS OF DETOMIDINE HYDROCHLORIDE IN GOATS

OpenAIRE

A. N. Tunio., A. B. Kalhoro and I.H. Kathio1

2003-01-01

The sedative and analgesic effects of three dose rates of detomidine (40, 50 and 60µg/kg body weight) were studied in six goats. Moderate to deep sedation occurred after administration of 40µg/kg of detomidine as compared to deep sedation produced by 50 and 60µg/kg of detomidine. The degree, onset and duration of sedation and onset and duration of maximum sedation were all dose dependent. Skin analgesia and recumbency were produced in all animals with higher doses (50 and 60µg/kg) and in thre...

Current UK dental sedation practice and the 'National Institute for Health and Care Excellence' (NICE) guideline 112: sedation in children and young people.

Science.gov (United States)

Coulthard, P; Craig, D; Holden, C; Robb, N D; Sury, M; Chopra, S; Holroyd, I

2015-04-24

Describe current dental sedation practice for under 19-year-olds in the UK and compare it with the recommendations of NICE guidance 112. Members of the Society for the Advancement of Anaesthesia in Dentistry and members of the Dental Sedation Teachers Group were invited to participate in an online survey. Two hundred and sixty-six dentists and doctors completed the survey. Eighty-two percent were operator and sedationist (operator-sedationist). Ninety-five percent provided written information and 94% obtained written consent. Eighty-four percent kept a written or electronic sedation record. Eighty-six percent complied with life support training expectations. Eighty-six percent had immediate access to resuscitation equipment. Sixty-seven percent of sedationists reported that treatment could not be completed under sedation for sedation was unsuccessful, 61% said they would schedule general anaesthesia and 54.5% would schedule advanced sedation care. Forty-nine percent believed that a dentist was an appropriate person to provide advanced sedation for 12-18 years. Only 24% thought a dentist should provide advanced sedation for childrensedation was thought to be primary care by 33% and secondary care by 68%. We found good agreement between the current practice of sedation and the recommendations of the NICE guidance 112.

Estabilidade térmica das vitaminas A e E em rações e premixes vitamínicos para camarões Thermal stability of vitamins A and E in rations and vitamin premixes for shrimp

Directory of Open Access Journals (Sweden)

João Paulo de Sousa Prado

2011-03-01

Full Text Available O trabalho teve como objetivo avaliar a estabilidade térmica das vitaminas A e E em diferentes rações e premixes vitamínicos utilizados na carcinicultura. Foram utilizadas no experimento três rações comerciais peletilizadas e desintegradas em diferentes diâmetros e dois premixes vitamínicos. As amostras de cada dieta e de premixes foram acondicionadas em recipientes plásticos e armazenadas nas seguintes condições: ambiente refrigerado (6°C±2°C, ambiente climatizado (20°C±3°C e ambiente de estufa (40°C±3°C. Os teores das vitaminas foram determinados em triplicata nas amostras nos períodos 0 (controle, 5, 10, 15, 20, 25 e 30 dias, nas condições anteriormente descritas. Os resultados obtidos mostraram que o percentual médio das perdas de vitamina A nas rações foram de 65, 60 e 68% para os ambientes refrigerado, climatizado e em estufa, respectivamente. Para o premix vitamínico A, o percentual médio de degradação foi de 78 a 87%, observando maiores perdas nos ambiente climatizado e de estufa. Com relação à vitamina E, observou-se nas rações perdas de 88 a 100%, verificando-se perdas totais para o armazenamento em ambiente de refrigeração e estufa. Já o premix vitamínico E as perdas foram de 71 a 82%. Durante o armazenamento da ração e dos premixes vitamínicos, as perdas por degradação térmica demonstraram falta de estabilidade das vitaminas lipossolúveis na estrutura das rações e premixes, utilizados na alimentação de camarões.The study aimed to evaluate the thermal stability of vitamins A and E on different rations and vitamin premixes used in shrimp farming. Three commercial rations pelleted and disintegrated in two different diameters and two vitamin premixes were used in the experiment. Samples of each ration and premixes were placed in plastic containers and stored under the following conditions: refrigerated environment (6°C±2°C, acclimatized environment (20°C±3°C and greenhouse

At-home palliative sedation for end-of-life cancer patients.

Science.gov (United States)

Alonso-Babarro, Alberto; Varela-Cerdeira, Maria; Torres-Vigil, Isabel; Rodríguez-Barrientos, Ricardo; Bruera, Eduardo

2010-07-01

Using a decision-making and treatment checklist developed to facilitate the at-home palliative sedation process, we assessed the incidence and efficacy of palliative sedation for end-of-life cancer patients with intractable symptoms who died at home. We retrospectively reviewed the medical records of 370 patients who were followed by a palliative home care team. Twenty-nine of 245 patients (12%) who died at home had received palliative sedation. The mean age of the patients who received palliative sedation was 58 +/- 17 years, and the mean age of the patients who did not receive palliative sedation was 69 +/- 15 years (p = 0.002). No other differences were detected between patients who did or did not receive palliative sedation. The most common indications for palliative sedation were delirium (62%) and dyspnea (14%). Twenty-seven patients (93%) received midazolam for palliative sedation (final mean dose of 74 mg), and two (7%) received levomepromazine (final mean dose of 125 mg). The mean time between palliative sedation initiation and time of death was 2.6 days. In 13 of the cases (45%), the palliative sedation decision was made with the patient and his or her family members, and in another 13 patients (45%), the palliative sedation decision was made only with the patient's family members. We concluded that palliative sedation may be used safely and efficaciously to treat dying cancer patients with refractory symptoms at home.

Experimental study of the structure of rich premixed 1,3-butadiene/CH4/O2/Ar flame.

OpenAIRE

Gueniche , Hadj-Ali; Glaude , Pierre-Alexandre; Fournet , René; Battin-Leclerc , Frédérique

2006-01-01

traduit de Fizika Goreniya I Vzryva, 2006, 42, 89-95.; The structure of a laminar rich premixed 1,3-C4H6/CH4/O2/Ar flame have been investigated. 1,3-Butadiene, methane, oxygen and argon mole fractions are 0.033; 0.2073; 0.3315, and 0.4280, respectively, for an equivalent ratio of 1.80. The flame has been stabilized on a burner at a pressure of 6.7 kPa (50 Torr). The concentration profiles of stable species were measured by gas chromatography after sampling with a quartz probe. Quantified spec...

Success rate of IR midazolam sedation in combination with C-CLAD in pediatric dental patients—a prospective observational study

Directory of Open Access Journals (Sweden)

Malka Ashkenazi

2014-03-01

Full Text Available Objective. To evaluate the success rate of intra-rectal (IR midazolam in combination with nitrous oxide/oxygen (N2O sedation in young uncooperative dental patients when the local anesthesia is delivered by a computerized controlled local anesthetic delivery (C-CLAD.Study Design. This observational study consisted of 219 uncooperative children (age: 4.3 ± 1.69 y who received IR midazolam (0.4 mg/kg and N2O to complete their dental treatment. Measured variables included: child’s pain disruptive behavior during delivery of anesthesia by C-CLAD (CHEOP Scale, child behavior during treatment (Houpt scale, dental procedure performed, and side effects that appeared during treatment.Results. There was a high level of cooperation (mean score: 6.69 ± 2.1 during administration of local anesthesia. Good-to-excellent behavior was shown by 87% of the children during treatment. Planned treatment was completed by 184 (92% patients. No statistically significant changes were noticed in the oxygen saturation levels before and after treatment. Children with side effects included 3 (1.3% with nistagmus, 5 (2.3% with diplopia, and 18 (8.2% with hiccups. Three consecutive sedations decreased the overall behavior score by 5.7% compared to the first appointment (p < .05.Conclusions. IR midazolam-N2O sedation in combination with C-CLAD is very effective for delivery of dental treatment to young uncooperative children.

Sedation practice among Nigerian radiology residents

African Journals Online (AJOL)

Background: Providing safe and effective sedation to patients, especially those with multiple medical problems, can be ... This study aimed to determine knowledge, attitude and practice of Nigerian radiology ..... works. Conclusion. Sedation and resuscitation are an integral part of radiology .... An evaluation of a virtual reality.

Premixed combustion on ceramic foam burners

NARCIS (Netherlands)

Bouma, P.H.; Goey, de L.P.H.

1999-01-01

Combustion of a lean premixed methane–air mixture stabilized on a ceramic foam burner has been studied. The stabilization of the flame in the radiant mode has been simulated using a one-dimensional numerical model for a burner stabilized flat-flame, taking into account the heat transfer between the

Evaluation of adult outpatient magnetic resonance imaging sedation practices: are patients being sedated optimally?

International Nuclear Information System (INIS)

Middelkamp, J.E.; Forster, B.B; Keogh, C.; Lennox, P.; Mayson, K.

2009-01-01

To evaluate the use of anxiolytics in adult outpatient magnetic resonance imaging (MRI) centres and to determine whether utilisation is optimal based on the pharmacology of the drugs used, who prescribes these drugs, and how patients are managed after administration. Identical paper and Web-based surveys were used to anonymously collect data about radiologists' use of anxiolytic agents for adult outpatient MRI examinations. The survey questions were about the type of facility, percentage of studies that require sedation, the drug used and route of administration, who orders the drug, timing of administration, patient monitoring during and observation after the study, use of a dedicated nurse for monitoring, and use of standard sedation and discharge protocols. The χ2 analysis for statistical association among variables was used. Eighty-five of 263 surveys were returned (32% response rate). The radiologist ordered the medication (53%) in slightly more facilities than the referring physician (44%) or the nurse. Forty percent of patients received medication 15-30 minutes before MRI, which is too early for peak effect of oral or sublingual drugs. Lorazepam was most commonly used (64% first choice). Facilities with standard sedation protocols (56%) were more likely to use midazolam than those without standard sedation protocols (17% vs 10%), to have a nurse for monitoring (P = .032), to have standard discharge criteria (P = .001), and to provide written information regarding adverse effects (P = .002). Many outpatients in MRI centres may be scanned before the peak effect of anxiolytics prescribed. A standard sedation protocol in such centres is associated with a more appropriate drug choice, as well as optimized monitoring and postprocedure care. (author)

Sedation practice in Nordic and non-Nordic ICUs: a European survey.

Science.gov (United States)

Egerod, Ingrid; Albarran, John W; Ring, Mette; Blackwood, Bronagh

2013-07-01

A trend towards lighter sedation has been evident in many intensive care units (ICUs). The aims of the survey were to describe sedation practice in European ICUs and to compare sedation practice in Nordic and non-Nordic countries. A cross-sectional survey of ICU nurses attending the fourth European federation of Critical Care Nursing associations (EfCCNa) in Denmark, 2011. Data included use of protocols; sedation, pain and delirium assessment tools; collaborative decision-making; sedation and analgesic medications; and educational preparation related to sedation. Response rate was 42% (n = 291) from 22 countries where 53% (n = 148) used sedation protocols. Nordic nurses reported greater use of sedation (91% versus 67%, p Nordic nurses. Decision-making on sedation was more inter-professionally collaborative in Nordic ICUs (83% versus 61%, p Nordic nurses reported greater consistency in maintaining circadian rhythm (66% versus 49%, p Nordic context might be more germane to the goal of lighter sedation and better pain management. Our study raises awareness of current sedation practice, paving the way towards optimized ICU sedation management. © 2013 The Authors. Nursing in Critical Care © 2013 British Association of Critical Care Nurses.

The proportionate value of proportionality in palliative sedation.

Science.gov (United States)

Berger, Jeffrey T

2014-01-01

Proportionality, as it pertains to palliative sedation, is the notion that sedation should be induced at the lowest degree effective for symptom control, so that the patient's consciousness may be preserved. The pursuit of proportionality in palliative sedation is a widely accepted imperative advocated in position statements and guidelines on this treatment. The priority assigned to the pursuit of proportionality, and the extent to which it is relevant for patients who qualify for palliative sedation, have been overstated. Copyright 2014 The Journal of Clinical Ethics. All rights reserved.

Sedation with alfentanil and propofol for rhizotomies

African Journals Online (AJOL)

M Jansen van Rensburg

Deep sedation can be avoided by maximising analgesia, and keeping patients ..... sedation and memory effects of propofol, midazolam, isoflurane, and alfentanil in healthy ... electroencephalogram predicts conscious processing of information.

Crossed-Plane Imaging of Premixed Turbulent Combustion Processes

National Research Council Canada - National Science Library

Gouldin, F

2003-01-01

.... Rayleigh scattering from premixed flames can be used for temperature imaging, and we have developed crossed-plane Rayleigh imaging in order to measure with high-resolution instantaneous temperature...

Sedative-hypnotic drug use among community-dwelling elderly in Taiwan.

Science.gov (United States)

Tseng, Han-Yun; Yu, Shu-Han; Lee, Chun-Yi; Huang, Wen-Hao; Huang, Seng-Loong; Wu, Chi-Shin; Chiu, Yen-Feng; Hsiung, Chao A

2018-03-21

Sedative-hypnotic medication use has been related to severe adverse events and risks. This study investigated the prevalence of and characteristics associated with the use of sedatives and hypnotics among community-dwelling elderly persons aged 65 years and over in Taiwan. A representative sample of community-dwelling adults was recruited. Clinical and sociodemographic data were collected for assessing physical, mental, and cognitive functioning and disorders. Sedatives and hypnotics use was determined via both self-reporting and prescription records. Logistic regression modeling was used to evaluate associations between sedative-hypnotic use and demographic and health status. Among the 3,978 participants aged 65 years and over, the rate of sedative-hypnotic use was 19.7% (n = 785). 4.5% (n = 35) of users reported sedative-hypnotic use without a doctor's prescription. Several sociodemographic characteristics were positively associated with sedative and hypnotic use, including older age, female gender, higher education level, married status, unemployment, and current alcohol consumption. Comorbid chronic and cardiovascular diseases, mental illness, depression, pain, and sleep problems also increased the likelihood of sedative-hypnotic use. This study is one of the largest pioneer studies to date to survey sedatives-hypnotics use among community-dwelling elderly. One in five community-dwelling older adults reported sedative-hypnotic drugs use in Taiwan, and about 5% of sedative and/or hypnotics usage was without a doctor's prescription. Findings could be helpful for drug-use safety interventions to identify target geriatric patients who are in general at higher risk of downstream harm associated with sedative-hypnotic use in geriatric patients.

A favorable course of palliative sedation: searching for indicators using caregivers' perspectives.

Science.gov (United States)

Brinkkemper, Tijn; Rietjens, Judith A C; Deliens, Luc; Ribbe, Miel W; Swart, Siebe J; Loer, Stephan A; Zuurmond, Wouter W A; Perez, Roberto S G M

2015-03-01

Comparing characteristics of a favorable sedation course during palliative sedation to a less favorable course based on the reports Dutch physicians and nurses. Cases identified as having a favorable sedation course less often concerned a male patient (P = .019 nurses' cases), reached the intended sedation depth significantly quicker (P sedation (P = .015 physicians' cases), and had a shorter total duration of sedation compared (P sedation course. A favorable course during palliative sedation seems more probable when health care professionals report on a (relatively) shorter time to reach the required depth of sedation and when a deeper level of sedation can be obtained. © The Author(s) 2013.

Thermal stability of vitamins A and E in rations and vitamin premixes for shrimp

OpenAIRE

Prado, João Paulo de Sousa; Cavalheiro, José Marcelino Oliveira; Silva, Fernanda Vanessa Gomes da; Queiroga Neto, Vicente; Bora, Pushkar Singh; Cavalheiro, Thiago Brandão

2011-01-01

O trabalho teve como objetivo avaliar a estabilidade térmica das vitaminas A e E em diferentes rações e premixes vitamínicos utilizados na carcinicultura. Foram utilizadas no experimento três rações comerciais peletilizadas e desintegradas em diferentes diâmetros e dois premixes vitamínicos. As amostras de cada dieta e de premixes foram acondicionadas em recipientes plásticos e armazenadas nas seguintes condições: ambiente refrigerado (6°C±2°C), ambiente climatizado (20°C&p...

When there are no good choices: illuminating the borderland between proportionate palliative sedation and palliative sedation to unconsciousness.

Science.gov (United States)

Reid, Thomas T; Demme, Richard A; Quill, Timothy E

2011-01-01

Despite state-of-the-art palliative care, some patients will require proportionate palliative sedation as a last-resort option to relieve intolerable suffering at the end of life. In this practice, progressively increasing amounts of sedation are provided until the target suffering is sufficiently relieved. Uncertainty and debate arise when this practice approaches palliative sedation to unconsciousness (PSU), especially when unconsciousness is specifically intended or when the target symptoms are more existential than physical. We constructed a case series designed to highlight some of the common approaches and challenges associated with PSU and the more aggressive end of the spectrum of proportionate palliative sedation as retrospectively identified by palliative care consultants over the past 5 years from a busy inpatient palliative care service at a tertiary medical center in Rochester (NY, USA). Ten cases were identified as challenging by the palliative care attendings, of which four were selected for presentation for illustrative purposes because they touched on central issues including loss of capacity, the role of existential suffering, the complexity of clinical intention, the role of an institutional policy and use of anesthetics as sedative agents. Two other cases were selected focusing on responses to two special situations: a request for PSU that was rejected; and anticipatory planning for total sedation in the future. Although relatively rare, PSU and more aggressive end-of-the-spectrum proportionate palliative sedation represent responses to some of the most challenging cases faced by palliative care clinicians. These complex cases clearly require open communication and collaboration among caregivers, patients and family. Knowing how to identify these circumstances, and how to approach these interventions of last resort are critical skills for practitioners who take care of patients at the end of life.

Analgesia, sedation, and memory of intensive care.

Science.gov (United States)

Capuzzo, M; Pinamonti, A; Cingolani, E; Grassi, L; Bianconi, M; Contu, P; Gritti, G; Alvisi, R

2001-09-01

The purpose of this article was to investigate the relationship between analgesia, sedation, and memory of intensive care. One hundred fifty-two adult, cooperative intensive care unit (ICU) patients were interviewed 6 months after hospital discharge about their memory of intensive care. The patient was considered to be cooperative when he/she was aware of self and environment at the interview. The patients were grouped as follows: A (45 patients) substantially no sedation, B (85) morphine, and C (22) morphine and other sedatives. The patients having no memory of intensive care were 38%, 34%, and 23% respectively, in the three groups. They were less ill, according to SAPS II (P memories was not different among the three groups. Females reported at least one emotional memory more frequently than males (odds ratio 4.17; 95% CI 10.97-1.59). The patients receiving sedatives in the ICU are not comparable with those receiving only opiates or nothing, due to the different clinical condition. The lack of memory of intensive care is present in one third of patients and is influenced more by length of stay in ICU than by the sedation received. Sedation does not influence the incidence of factual, sensation, and emotional memories of ICU admitted patients. Females have higher incidences of emotional memories than males. Copyright 2001 by W.B. Saunders Company

Premixed burner experiments: Geometry, mixing, and flame structure issues

Energy Technology Data Exchange (ETDEWEB)

Gupta, A.K.; Lewis, M.J.; Gupta, M. [Univ of Maryland, College Park, MD (United States)] [and others

1995-10-01

This research program is exploring techniques for improved fuel-air mixing, with the aim of achieving combustor operations up to stoichiometric conditions with minimal NO x and maximum efficiency. The experimental studies involve the use of a double-concentric natural gas burner that is operable in either premixed or non-premixed modes, and the system allows systematic variation of equivalence ratio, swirl strength shear length region and flow momentum in each annulus. Flame structures formed with various combinations of swirl strengths, flow throughput and equivalence ratios in premixed mode show the significant impact of swirl flow distribution on flame structure emanating from the mixedness. This impact on flame structure is expected to have a pronounced effect on the heat release rate and the emission of NO{sub x}. Thus, swirler design and configuration remains a key factor in the quest for completely optimized combustion. Parallel numerical studies of the flow and combustion phenomena were carried out, using the RSM and thek-{epsilon} turbulence models. These results have not only indicated the strengths and limitations of CFD in performance and pollutants emission predictions, but have provided guidelines on the size and strength of the recirculation produced and the spatio-temporal structure of the combustion flowfield. The first stage of parametric studies on geometry and operational parameters at Morgan State University have culminated in the completion of a one-dimensional flow code that is integrated with a solid, virtual model of the existing premixed burner. This coupling will provide the unique opportunity to study the impact of geometry on the flowfield and vice-versa, with particular emphasis on concurrent design optimization.

Sedation and Monitoring in the Pediatric Patient during Gastrointestinal Endoscopy.

Science.gov (United States)

Chung, Hyun Kee; Lightdale, Jenifer R

2016-07-01

Sedation is a fundamental component of pediatric gastrointestinal procedures. The 2 main types of sedation for pediatric endoscopy remain general anesthesia and procedural sedation. Although anesthesiologist-administered sedation protocols are more common, there is no ideal regimen for endoscopy in children. This article discusses specific levels of sedation for endoscopy as well as various regimens that can be used to achieve each. Risks and considerations that may be specific to performing gastrointestinal procedures in children are reviewed. Finally, potential future directions for sedation and monitoring that may change the practice of pediatric gastroenterology and ultimately patient outcomes are examined. Copyright © 2016 Elsevier Inc. All rights reserved.

Comfort and patient-centred care without excessive sedation

DEFF Research Database (Denmark)

Vincent, Jean-Louis; Shehabi, Yahya; Walsh, Timothy S

2016-01-01

We propose an integrated and adaptable approach to improve patient care and clinical outcomes through analgesia and light sedation, initiated early during an episode of critical illness and as a priority of care. This strategy, which may be regarded as an evolution of the Pain, Agitation...... and Delirium guidelines, is conveyed in the mnemonic eCASH-early Comfort using Analgesia, minimal Sedatives and maximal Humane care. eCASH aims to establish optimal patient comfort with minimal sedation as the default presumption for intensive care unit (ICU) patients in the absence of recognised medical...... requirements for deeper sedation. Effective pain relief is the first priority for implementation of eCASH: we advocate flexible multimodal analgesia designed to minimise use of opioids. Sedation is secondary to pain relief and where possible should be based on agents that can be titrated to a prespecified...

Oral Sedation in the Dental Office.

Science.gov (United States)

Sebastiani, Francesco R; Dym, Harry; Wolf, Joshua

2016-04-01

This article highlights the commonly used medications used in dentistry and oral surgery. General dentists and specialists must be knowledgeable about the pharmacology of the drugs currently available along with their risks and benefits. Enteral sedation is a useful adjunct for the treatment of anxious adult and pediatric patients. When enteral sedation is used within the standards of care, the interests of the public and the dental profession are served through a cost-effective, effective service that can be widely available. Oral sedation enables dentists to provide dental care to millions of individuals who otherwise would have unmet dental needs. Copyright © 2016 Elsevier Inc. All rights reserved.

Subgrid scale modeling in large-Eddy simulation of turbulent combustion using premixed fdlamelet chemistry

NARCIS (Netherlands)

Vreman, A.W.; Oijen, van J.A.; Goey, de L.P.H.; Bastiaans, R.J.M.

2009-01-01

Large-eddy simulation (LES) of turbulent combustion with premixed flamelets is investigated in this paper. The approach solves the filtered Navier-Stokes equations supplemented with two transport equations, one for the mixture fraction and another for a progress variable. The LES premixed flamelet

Suboptimal palliative sedation in primary care: an exploration.

Science.gov (United States)

Pype, Peter; Teuwen, Inge; Mertens, Fien; Sercu, Marij; De Sutter, An

2018-02-01

Palliative sedation is a therapeutic option to control refractory symptoms in terminal palliative patients. This study aims at describing the occurrence and characteristics of suboptimal palliative sedations in primary care and at exploring the way general practitioners (GPs) experience suboptimal palliative sedation in their practice. We conducted a mixed methods study with a quantitative prospective survey in primary care and qualitative semi-structured interviews with GPs. The research team defined suboptimal palliative sedation as a time interval until deep sleep >1.5 h and/ or >2 awakenings after the start of the unconsciousness. Descriptive statistics were calculated on the quantitative data. Thematic analysis was used to analyse interview transcripts. We registered 63 palliative sedations in 1181 home deaths, 27 forms were completed. Eleven palliative sedations were suboptimal: eight due to the long time span until deep sleep; three due the number of unintended awakenings. GPs' interview analysis revealed two major themes: the shifting perception of failure and the burden of responsibility. Suboptimal palliative sedation occurs frequently in primary palliative care. Efficient communication towards family members is needed to prevent them from having unrealistic expectations and to prevent putting pressure on the GP to hasten the procedure. Sharing the burden of decision-making during the procedure with other health care professionals might diminish the heavy responsibility as perceived by GPs.

An Investigation of a Hybrid Mixing Model for PDF Simulations of Turbulent Premixed Flames

Science.gov (United States)

Zhou, Hua; Li, Shan; Wang, Hu; Ren, Zhuyin

2015-11-01

Predictive simulations of turbulent premixed flames over a wide range of Damköhler numbers in the framework of Probability Density Function (PDF) method still remain challenging due to the deficiency in current micro-mixing models. In this work, a hybrid micro-mixing model, valid in both the flamelet regime and broken reaction zone regime, is proposed. A priori testing of this model is first performed by examining the conditional scalar dissipation rate and conditional scalar diffusion in a 3-D direct numerical simulation dataset of a temporally evolving turbulent slot jet flame of lean premixed H2-air in the thin reaction zone regime. Then, this new model is applied to PDF simulations of the Piloted Premixed Jet Burner (PPJB) flames, which are a set of highly shear turbulent premixed flames and feature strong turbulence-chemistry interaction at high Reynolds and Karlovitz numbers. Supported by NSFC 51476087 and NSFC 91441202.

Investigation of non-premixed flame combustion characters in GO2/GH2 shear coaxial injectors using non-intrusive optical diagnostics

Science.gov (United States)

Dai, Jian; Yu, NanJia; Cai, GuoBiao

2015-12-01

Single-element combustor experiments are conducted for three shear coaxial geometry configuration injectors by using gaseous oxygen and gaseous hydrogen (GO2/GH2) as propellants. During the combustion process, several spatially and timeresolved non-intrusive optical techniques, such as OH planar laser induced fluorescence (PLIF), high speed imaging, and infrared imaging, are simultaneously employed to observe the OH radical concentration distribution, flame fluctuations, and temperature fields. The results demonstrate that the turbulent flow phenomenon of non-premixed flame exhibits a remarkable periodicity, and the mixing ratio becomes a crucial factor to influence the combustion flame length. The high speed and infrared images have a consistent temperature field trend. As for the OH-PLIF images, an intuitionistic local flame structure is revealed by single-shot instantaneous images. Furthermore, the means and standard deviations of OH radical intensity are acquired to provide statistical information regarding the flame, which may be helpful for validation of numerical simulations in future. Parameters of structure configurations, such as impinging angle and oxygen post thickness, play an important role in the reaction zone distribution. Based on a successful flame contour extraction method assembled with non-linear anisotropic diffusive filtering and variational level-set, it is possible to implement a fractal analysis to describe the fractal characteristics of the non-premixed flame contour. As a result, the flame front cannot be regarded as a fractal object. However, this turbulent process presents a self-similarity characteristic.

[Psychomotor agitation, pharmaceutical sedation and psychiatric emergency in psychotic patients].

Science.gov (United States)

Passamar, M; Tellier, O; Vilamot, B

2011-12-01

Psychomotor agitation, very common among psychiatric emergencies, raises the question of pharmaceutical sedation, its indications, and its issues, notably with regard to the observance in postemergency. A new approach to sedation places it within its therapeutic aim and also takes into account the sometimes harmful impact on the course of the patient's care. A pretherapeutical, analysis both clinical and environmental is crucial. The time spent on the initial meeting and assessment is essential. The evolution of professional practices in mental health allows us to distinguish three kinds of sedation (vigilance, behaviour and psychical) that guide the choice and the mode of psychotropic drug use. The harmful effects of an ever-increasing use of sedation is debated. The use of atypical antipsychotics and injectable forms is argued. Early psychical sedation is preferable to the obsolete practice of vigilance sedation and to behavioural sedation with its limited indications. The use of excessive or prolonged sedation might have a detrimental effect on the care offered after psychiatric emergency treatment. Copyright © 2011. Published by Elsevier Masson SAS.

Proposed Guideline Revisions for Dental Sedation and General Anesthesia: Why Target the Safest Level of Sedation?

Science.gov (United States)

Dionne, Raymond A

2016-09-01

Recently proposed revisions to the American Dental Association's Guidelines for the Use of Sedation and General Anesthesia by Dentists, aimed at improving safety in dental offices, differentiate between levels of sedation based on drug-induced changes in physiologic and behavioral states. However, the author of this op-ed is concerned the proposed revisions may have far-reaching and unintended consequences.

Moderate and deep nurse-administered propofol sedation is safe

DEFF Research Database (Denmark)

Jensen, Jeppe Thue; Møller, Ann; Hornslet, Pernille

2015-01-01

INTRODUCTION: Non-anaesthesiologist-administered propofol sedation (NAPS/NAAP) is increasingly used in many countries. Most regimens aim for light or moderate sedation. Little evidence on safety of deep NAPS sedation is available. The aim of this study was to explore the safety of intermittent deep...

Neural correlates of successful semantic processing during propofol sedation

NARCIS (Netherlands)

Adapa, Ram M.; Davis, Matthew H.; Stamatakis, Emmanuel A.; Absalom, Anthony R.; Menon, David K.

Sedation has a graded effect on brain responses to auditory stimuli: perceptual processing persists at sedation levels that attenuate more complex processing. We used fMRI in healthy volunteers sedated with propofol to assess changes in neural responses to spoken stimuli. Volunteers were scanned

Patient satisfaction with procedural sedation in the emergency department.

Science.gov (United States)

Johnson, Olivia G; Taylor, David McD; Lee, Marina; Ding, Juen-Li; Ashok, Aadith; Johnson, Damian; Peck, Daniel; Knott, Jonathan; Weinberg, Laurence

2017-06-01

The aim of this study was to determine patient satisfaction with procedural sedation as a function of nature of the procedure and depth of sedation. We undertook a prospective observational study of adult patients who received procedural sedation in two EDs (20 month period). The level of sedation was determined by an investigator, using the Observers Assessment of Anaesthesia/Sedation Scale (1 = awake to 6 = no response to noxious stimuli). Patient satisfaction was measured with the Iowa Satisfaction with Anaesthesia Scale after full recovery. This was self-administered, comprised 11 items (e.g. 'I felt pain') and has a score range of -3 (poor satisfaction) to +3 (very satisfied). A total of 163 patients were enrolled (51.2% men, mean age 50.7 years). The median (interquartile range) satisfaction score was 2.7 (0.7). Patient satisfaction was lower among patients who had orthopaedic procedures (median 2.6 vs 2.8, P patient satisfaction is high. Greater satisfaction is associated with deeper sedation, sedation with propofol and non-orthopaedic procedures. © 2017 Australasian College for Emergency Medicine and Australasian Society for Emergency Medicine.

Dry low NOx combustion system with pre-mixed direct-injection secondary fuel nozzle

Science.gov (United States)

Zuo, Baifang; Johnson, Thomas; Ziminsky, Willy; Khan, Abdul

2013-12-17

A combustion system includes a first combustion chamber and a second combustion chamber. The second combustion chamber is positioned downstream of the first combustion chamber. The combustion system also includes a pre-mixed, direct-injection secondary fuel nozzle. The pre-mixed, direct-injection secondary fuel nozzle extends through the first combustion chamber into the second combustion chamber.

A combined single-multiphase flow formulation of the premixing phase using the level set method

International Nuclear Information System (INIS)

Leskovar, M.; Marn, J.

1999-01-01

The premixing phase of a steam explosion covers the interaction of the melt jet or droplets with the water prior to any steam explosion occurring. To get a better insight of the hydrodynamic processes during the premixing phase beside hot premixing experiments, where the water evaporation is significant, also cold isothermal premixing experiments are performed. The specialty of isothermal premixing experiments is that three phases are involved: the water, the air and the spheres phase, but only the spheres phase mixes with the other two phases whereas the water and air phases do not mix and remain separated by a free surface. Our idea therefore was to treat the isothermal premixing process with a combined single-multiphase flow model. In this combined model the water and air phase are treated as a single phase with discontinuous phase properties at the water air interface, whereas the spheres are treated as usually with a multiphase flow model, where the spheres represent the dispersed phase and the common water-air phase represents the continuous phase. The common water-air phase was described with the front capturing method based on the level set formulation. In the level set formulation, the boundary of two-fluid interfaces is modeled as the zero set of a smooth signed normal distance function defined on the entire physical domain. The boundary is then updated by solving a nonlinear equation of the Hamilton-Jacobi type on the whole domain. With this single-multiphase flow model the Queos isothermal premixing Q08 has been simulated. A numerical analysis using different treatments of the water-air interface (level set, high-resolution and upwind) has been performed for the incompressible and compressible case and the results were compared to experimental measurements.(author)

Swozzle based burner tube premixer including inlet air conditioner for low emissions combustion

Science.gov (United States)

Tuthill, Richard Sterling; Bechtel, II, William Theodore; Benoit, Jeffrey Arthur; Black, Stephen Hugh; Bland, Robert James; DeLeonardo, Guy Wayne; Meyer, Stefan Martin; Taura, Joseph Charles; Battaglioli, John Luigi

2002-01-01

A burner for use in a combustion system of a heavy-duty industrial gas turbine includes a fuel/air premixer having an air inlet, a fuel inlet, and an annular mixing passage. The fuel/air premixer mixes fuel and air into a uniform mixture for injection into a combustor reaction zone. The burner also includes an inlet flow conditioner disposed at the air inlet of the fuel/air premixer for controlling a radial and circumferential distribution of incoming air. The pattern of perforations in the inlet flow conditioner is designed such that a uniform air flow distribution is produced at the swirler inlet annulus in both the radial and circumference directions. The premixer includes a swozzle assembly having a series of preferably air foil shaped turning vanes that impart swirl to the airflow entering via the inlet flow conditioner. Each air foil contains internal fuel flow passages that introduce natural gas fuel into the air stream via fuel metering holes that pass through the walls of the air foil shaped turning vanes. By injecting fuel in this manner, an aerodynamically clean flow field is maintained throughout the premixer. By injecting fuel via two separate passages, the fuel/air mixture strength distribution can be controlled in the radial direction to obtain optimum radial concentration profiles for control of emissions, lean blow outs, and combustion driven dynamic pressure activity as machine and combustor load are varied.

The effects of pre-mix on burn in ICF capsules

International Nuclear Information System (INIS)

Wilson, D C; Kyrala, G A; Jr, J F Benage; Wysocki, F J; Gunderson, M A; Herrman, H W; Cooley, J H; Welser-Sherrill, L; Garbett, W J; Horsfield, C J; Glebov, V Y; Yaakobi, B; Roberts, S A; Frenje, J

2008-01-01

Directly driven implosions at the Omega laser have tested the effects of pre-mix of Ar, Kr, and Xe in D 2 + 3 He filled glass micro-balloons. Diagnostics included: D+D and D+T neutron yields, D+ 3 He proton yields and spectra, Doppler broadened ion temperatures, time dependent neutron and proton burn rates, and time gated, high energy filtered, X-ray images. Yields are better calculated by XSN LTE than by non-LTE. Yields with a small amount of pre-mix, atom fractions of ∼5e-3 for Ar, 2e-3 Kr, and Xe for 5e-4, are more degraded than calculated, while the measured ion temperatures are the same as without pre-mix. There is also a decrease in fuel ρr. The neutron burn histories suggest that the early yield coming before the reflected shock strikes the incoming shell is un-degraded, with yield degradation occurring afterwards. Adding 20 atm % 3 He to pure D fuel seems to produce a similar degradation. Calculated gated X-ray images agree with observed when the reflected shock strikes the incoming shell, but are smaller than observed afterward. This partially explains yield degradation and both the low fuel and whole capsule ρr's observed in secondary T+D neutrons and slowing of the D+ 3 He protons. Neither LTE on non-LTE captures the degradation by 3 He or at low pre-mix levels, nor matches the large shell radii after impact of the reflected shock

Nurse-administered propofol sedation for endoscopy

DEFF Research Database (Denmark)

Jensen, J T; Vilmann, P; Horsted, T

2011-01-01

The aim of the present study was to perform a risk analysis during the implementation phase of nurse-administered propofol sedation (NAPS) and to validate our structured training program.......The aim of the present study was to perform a risk analysis during the implementation phase of nurse-administered propofol sedation (NAPS) and to validate our structured training program....

Dynamic-Stability Characteristics of Premixed Methane Oxy-Combustion

KAUST Repository

Shroll, Andrew P.

2012-01-01

This work explores the dynamic stability characteristics of premixed CH 4/O 2/CO 2 mixtures in a 50 kW swirl stabilized combustor. In all cases, the methane-oxygen mixture is stoichiometric, with different dilution levels of carbon dioxide used to control the flame temperature (T ad). For the highest T ad\\'s, the combustor is unstable at the first harmonic of the combustor\\'s natural frequency. As the temperature is reduced, the combustor jumps to fundamental mode and then to a low-frequency mode whose value is well below the combustor\\'s natural frequency, before eventually reaching blowoff. Similar to the case of CH 4/air mixtures, the transition from one mode to another is predominantly a function of the T ad of the reactive mixture, despite significant differences in laminar burning velocity and/or strained flame consumption speed between air and oxy-fuel mixtures for a given T ad. High speed images support this finding by revealing similar vortex breakdown modes and thus similar turbulent flame geometries that change as a function of flame temperature. Copyright © 2012 American Society of Mechanical Engineers.

MRI-compatible audio/visual system: impact on pediatric sedation

International Nuclear Information System (INIS)

Harned, R.K. II; Strain, J.D.

2001-01-01

Background. While sedation is necessary for much pediatric imaging, there are new alternatives that may help patients hold still without medication. Objective. We examined the effect of an audio/visual system consisting of video goggles and earphones on the need for sedation during magnetic resonance imaging (MRI). Materials and methods. All MRI examinations from May 1999 to October 1999 performed after installation of the MRVision 2000 (Resonance Technology, Inc.) were compared to the same 6-month period in 1998. Imaging and sedation protocols remained constant. Data collected included: patient age, type of examination, use of intravenous contrast enhancement, and need for sedation. The average supply charge and nursing cost per sedated patient were calculated. Results. The 955 patients from 1998 and 1,112 patients from 1999 were similar in demographics and examination distribution. There was an overall reduction in the percent of patients requiring sedation in the group using the video goggle system from 49 to 40 % (P < 0.001). There was no significant change for 0-2 years (P = 0.805), but there was a reduction from 53 to 40 % for age 3-10 years (P < 0.001) and 16 to 8 % for those older than 10 years (P < 0.001). There was a 17 % decrease in MRI room time for those patients whose examinations could be performed without sedation. Sedation costs per patient were $80 for nursing and $29 for supplies. Conclusion. The use of this video system reduced the number of children requiring sedation for MRI examination by 18 %. In addition to reducing patient risk, this can potentially reduce cost. (orig.)

A Nationwide Survey About Palliative Sedation Involving Japanese Palliative Care Specialists: Intentions and Key Factors Used to Determine Sedation as Proportionally Appropriate.

Science.gov (United States)

Hamano, Jun; Morita, Tatsuya; Ikenaga, Masayuki; Abo, Hirofumi; Kizawa, Yoshiyuki; Tunetou, Satoru

2018-03-01

Although there has long been debate about physicians' intentions and what physicians consider to be proportionally appropriate when performing palliative sedation, few large studies have been performed. To identify physicians' intentions when starting continuous deep sedation and to clarify what factors determine whether physicians regard sedation as proportionally appropriate in relation to expected survival, the patients' wishes, and refractoriness. A nationwide questionnaire survey of Japanese palliative care specialists was performed from August to December 2016. We defined continuous deep sedation as the continuous use of sedatives to relieve intolerable and refractory symptoms with the loss of consciousness until death. Of the 695 palliative care specialists enrolled, 440 were analyzed (response rate, 69%). A total of 95% and 87% of the physicians reported that they explicitly intended to perform symptom palliation and decrease consciousness levels, respectively. Moreover, 38% answered that they explicitly intended to maintain unconsciousness until death, and 11% reported that they intended to shorten survival to some extent. The respondents considered that continuous deep sedation is more appropriate when the predicted survival is shorter, the patients' wishes are consistent and clear, and confidence in the refractoriness of symptoms is higher. Japanese palliative care specialists explicitly intend to control symptoms and reduce the level of consciousness when performing continuous deep sedation, but there are differences in their intentions with regard to maintaining unconsciousness until death. Predicted survival, patients' wishes, and confidence in refractoriness are associated with physicians' judgment that sedation is proportionally appropriate. Copyright © 2017 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Recall of ICU Stay in Patients Managed With a Sedation Protocol or a Sedation Protocol With Daily Interruption.

Science.gov (United States)

Burry, Lisa; Cook, Deborah; Herridge, Margaret; Devlin, John W; Fergusson, Dean; Meade, Maureen; Steinberg, Marilyn; Skrobik, Yoanna; Olafson, Kendiss; Burns, Karen; Dodek, Peter; Granton, John; Ferguson, Niall; Jacka, Michael; Tanios, Maged; Fowler, Robert; Reynolds, Steven; Keenan, Sean; Mallick, Ranjeeta; Mehta, Sangeeta

2015-10-01

To 1) describe factual, emotional, and delusional memories of ICU stay for patients enrolled in the SLEAP (Daily sedation interruption in mechanically ventilated critically ill patients cared for with a sedation protocol) trial; 2) compare characteristics of patients with and without ICU recall, and patients with and without delusional memories; and 3) determine factors associated with delusional memories 28 days after ICU discharge. Prospective cohort. Sixteen North American medical and surgical ICUs. Critically ill, mechanically ventilated adults randomized in the SLEAP trial. Post-ICU interviews on days 3, 28, and 90 using the validated ICU Memory Tool. Overall, 289 of 297 ICU survivors (97%) (146 protocolized sedation and 143 protocolized sedation plus daily interruption patients) were interviewed at least once. Because there were no differences in recall status or types of memories between the two sedation groups, we present the findings for all patients rather than by study group. On days 3, 28, and 90, 28%, 26%, and 36% of patients, respectively, reported no recall of being in the ICU (overall perception, self-reported) (p = 0.75). Mean daily doses of benzodiazepines and opioids were lower in patients with no ICU recall than those with recall (p patients reporting no recall of ICU stay on day 3, 97% and 90% reported at least one factual and one emotional memory from ICU, respectively. Emotional memories declined with time after ICU discharge, particularly panic and confusion. Delusional memories 28 days after discharge were common (70%) yet unrelated to delirium (p = 0.84), recall status (p = 0.15), total dose of benzodiazepine (p = 0.78), or opioid (p = 0.21). Delusional memories were less likely with longer duration of mechanical ventilation (odds ratio, 0.955; 95% CI, 0.91-1.00; p = 0.04). Recall of ICU stay and types of memories reported were not influenced by the trial sedation strategy. Lack of ICU recall and delusional memories were common after ICU

Experiences of Family Members of Dying Patients Receiving Palliative Sedation.

Science.gov (United States)

Tursunov, Olga; Cherny, Nathan I; Ganz, Freda DeKeyser

2016-11-01

To describe the experience of family members of patients receiving palliative sedation at the initiation of treatment and after the patient has died and to compare these experiences over time.
. Descriptive comparative study.
. Oncology ward at Shaare Zedek Medical Center in Jerusalem, Israel.
. A convenience sample of 34 family members of dying patients receiving palliative sedation. 
. A modified version of a questionnaire describing experiences of family members with palliative sedation was administered during palliative sedation and one to four months after the patient died. Descriptive statistics were used to describe the results of the questionnaire, and appropriate statistical analyses were conducted for comparisons over time.
. Experiences of family members and time.
. Most relatives were satisfied with the sedation and staff support. Palliative sedation was experienced as an ethical way to relieve suffering. However, one-third felt that it shortened the patient's life. An explanation of the treatment was given less than half of the time and was usually given on the same day treatment was started. This explanation was given by physicians and nurses. Many felt that they were not ready for changes in the patient's condition and wanted increased opportunities to discuss the treatment with oncology care providers. No statistically significant differences in experiences were found over time. 
. Relatives' experiences of palliative sedation were generally positive and stable over time. Important experiences included timing of the initiation of sedation, timing and quality of explanations, and communication.
. Nurses should attempt to initiate discussions of the possible role of sedation in the event of refractory symptoms and follow through with continued discussions. The management of refractory symptoms at the end of life, the role of sedation, and communication skills associated with decision making related to palliative sedation should be a

SEDATIVE AND ANALGESIC EFFECTS OF DETOMIDINE HYDROCHLORIDE IN GOATS

Directory of Open Access Journals (Sweden)

A. N. Tunio., A. B. Kalhoro and I.H. Kathio1

2003-07-01

Full Text Available The sedative and analgesic effects of three dose rates of detomidine (40, 50 and 60µg/kg body weight were studied in six goats. Moderate to deep sedation occurred after administration of 40µg/kg of detomidine as compared to deep sedation produced by 50 and 60µg/kg of detomidine. The degree, onset and duration of sedation and onset and duration of maximum sedation were all dose dependent. Skin analgesia and recumbency were produced in all animals with higher doses (50 and 60µg/kg and in three animals with lower dose (40µg/kg. Duration of recumbency was 22.66 ± 1.45, 35.16 ± 1.68 and 55.66 ± 1.64 minutes after administration of 40, 50 and 60µg/kg of detomidine, respectively.

The flow field structure of highly stabilized partially premixed flames in a concentric flow conical nozzle burner with coflow

KAUST Repository

Elbaz, Ayman M.

2015-08-29

The stability limits, the stabilization mechanism, and the flow field structure of highly stabilized partially premixed methane flames in a concentric flow conical nozzle burner with air co-flow have been investigated and presented in this work. The stability map of partial premixed flames illustrates that the flames are stable between two extinction limits. A low extinction limit when partial premixed flames approach non-premixed flame conditions, and a high extinction limit, with the partial premixed flames approach fully premixed flame conditions. These two limits showed that the most stable flame conditions are achieved at a certain degree of partial premixed. The stability is improved by adding air co-flow. As the air co-flow velocity increases the most stable flames are those that approach fully premixed. The turbulent flow field of three flames at 0, 5, 10 m/s co-flow velocity are investigated using Stereo Particle Image Velocimetry (SPIV) in order to explore the improvement of the flame stability due to the use of air co-flow. The three flames are all at a jet equivalence ratio (Φj) of 2, fixed level of partial premixing and jet Reynolds number (Rej) of 10,000. The use of co-flow results in the formation of two vortices at the cone exit. These vortices act like stabilization anchors for the flames to the nozzle tip. With these vortices in the flow field, the reaction zone shifts toward the reduced turbulence intensity at the nozzle rim of the cone. Interesting information about the structure of the flow field with and without co-flow are identified and reported in this work.

Anaesthesia and Sedation for the Autistic Patient.

Science.gov (United States)

Sacoor, Sarah

2017-01-01

Autism is a disability that affects how a person communicates and relates to the world around them. Patients on the autistic spectrum may be referred to a Special Care Dentistry service to be managed under sedation or general anaesthetic, as their visit to the dentist can be stressful and disruptive to their routine. As it is a spectrum disorder, each patient needs to be assessed individually in order to determine whether sedation or general anaesthetic would be appropriate for them. Some autistic patients may have good verbal communication and mild learning difficulties, and may be able to tolerate treatment under local anaesthetic with behavioural management alone. On the other end of the spectrum, patients with severe autism and learning difficulties may not permit the dentist to even examine them and will require a general anaesthetic. There will also be patients on the autistic spectrum who are suitable for conscious sedation depending on their level of learning difficulty and cooperation. Oral and transmucosal sedation can also be useful for providing presedation to a patient to facilitate venous access. In order to minimise distress to the patient, it is important that adequate sedation, anaesthesia and analgesia are achieved both perioperatively and post-operatively.

Paediatric conscious sedation: views and experience of specialists in paediatric dentistry.

Science.gov (United States)

Woolley, S M; Hingston, E J; Shah, J; Chadwick, B L

2009-09-26

The objectives were three-fold: to investigate the level of conscious sedation training received prior to and during specialist training in paediatric dentistry; to establish the use of conscious sedation during and following specialisation; and to determine the attitudes of specialists in paediatric dentistry to conscious sedation. A self-administered postal questionnaire was sent to all specialists in paediatric dentistry registered with the General Dental Council in January 2008. Non-responders were contacted again after a four-week period. A response rate of 60% was achieved. Of the 122 respondents, 67 (55%) had received sedation training as an undergraduate; 89 (75%) had been trained during specialisation. All respondents performed dental treatment under sedation as a trainee and the majority used nitrous oxide inhalation sedation (NOIS). Over 90% of respondents felt that NOIS should be available to all children, both in appropriate primary care settings and in hospitals. One hundred and twenty-one (99%) respondents thought that all trainees in paediatric dentistry should have sedation training. The most popular form of sedation amongst specialists in paediatric dentistry was NOIS. However, some of the respondents felt that children should have access to other forms of sedation in both the primary care and hospital settings. Additional research on other forms of sedation is required to evaluate their effectiveness and safety.

Auditory processing during deep propofol sedation and recovery from unconsciousness

OpenAIRE

Koelsch, Stefan; Heinke, Wolfgang; Sammler, Daniela; Olthoff, Derk

2006-01-01

Objective Using evoked potentials, this study investigated effects of deep propofol sedation, and effects of recovery from unconsciousness, on the processing of auditory information with stimuli suited to elicit a physical MMN, and a (music-syntactic) ERAN. Methods Levels of sedation were assessed using the Bispectral Index (BIS) and the Modified Observer's Assessment of Alertness and Sedation Scale (MOAAS). EEG-measurements were performed during wakefulness, deep propofol sedation (MOAAS 2–3...

Rectal Sedation with Thiopental in Children

International Nuclear Information System (INIS)

Granados, Ana Maria; Levy, Wilma; Badiel, Marisol; Cruz Libreros, Alejandro; Toro Gutierrez, Juan Sebastian

2012-01-01

Objective: to determine the effectiveness of a rectal sedation protocol with sodium thiopental in children undergoing diagnostic imaging studies in a level-four-complexity health care facility. Materials and Methods: this case series observational study was developed between the months of January and March 2004 in the Fundacion clinica Valle del Lili. All pediatric patients between the ages of three months and eight years of age who underwent an imaging study were included. A dose of 25-40 mg/kg of sodium thiopental was administered rectally. Successful sedation was defined as one that allowed the successful completion of the study with the least number of motion artifacts. The features of the sedation and the adverse effects were evaluated. Results: the study population included 103 children with a median age of two years. The imaging studies were successfully concluded in 97% of the patients. The average total time until complete awakening was 2.9 hours. With respect to the interruption of sedation, we found statistically significant differences between the children who were kept awake the night before the procedure and those who were not. The most common adverse effect was diarrhea, which was recorded in 13 patients. Five of the patients required a supplemental dose of the sedative. There were two cases of increased salivation and one of vomiting, yet they resolved spontaneously. Conclusions: this rectal sodium thiopental protocol is a safe and effective procedure for the completion of diagnostic imaging studies in the pediatric population at our health care center.

Nurse administered propofol sedation for pulmonary endoscopies requires a specific protocol

DEFF Research Database (Denmark)

Jensen, Jeppe Thue; Banning, Anne-Marie; Clementsen, Paul

2012-01-01

This study provides an evaluation and risk analysis of propofol sedation for endoscopic pulmonary procedures according to our unit's "gastroenterologic nurse-administered propofol sedation (NAPS) guideline".......This study provides an evaluation and risk analysis of propofol sedation for endoscopic pulmonary procedures according to our unit's "gastroenterologic nurse-administered propofol sedation (NAPS) guideline"....

Pediatric Gastrointestinal Endoscopic Sedation: A 2010 Nationwide Survey in Taiwan

Directory of Open Access Journals (Sweden)

Po-Hon Chen

2012-06-01

Conclusion: A majority of pediatric EGD in Taiwan was performed under sedation and applied more often to younger children. Endoscopists were more satisfied during EGD when practicing sedation. This survey should help formulate updated practice guidelines and policies regarding endoscopic sedation.

Intensifying existing premix therapy (BIAsp 30) with BIAsp 50 and BIAsp 70

DEFF Research Database (Denmark)

Brito, Miguel; Ligthelm, Robert Jan; Boemi, Massimo

2011-01-01

In 2009, consensus guidelines were published on intensification of insulin therapy using the premix analog biphasic insulin aspart (BIAsp) 30 in the treatment of type 2 diabetes, based on the recommendations of an international, independent expert panel. The guidelines included recommendations an...... assist physicians in introducing mid-/high-ratio premixes to optimize the insulin therapy of patients with type 2 diabetes who are failing to achieve glycemic targets on a BIAsp 30 BID or TID regimen....

ASSESSMENT OF FLOW AND TECHNOLOGICAL BEHAVIOR OF FRENCH BREAD PREMIXES

Directory of Open Access Journals (Sweden)

E. VALDUGA

2008-08-01

Full Text Available

In this work formulations of French bread premixes were investigated. The premixes were based on blends of Argentinean and Brazilian wheat. The bread produced with the mixtures was compared to the bread obtained with standard flour, which did not contain any additives. The flour was characterized by physico-chemical and biochemical analysis (humidity, ashes, water absorption, color, gluten index, flour strength and a-amylase activity. The bread rolls were prepared using a standard formulation (without additives and two different formulations, using ascorbic acid, a-amylase, esterlac, soybean flour and diacetyl tartaric acid emulsifier. The physico-chemical analysis results indicate that the standard flour is better than the formulations. Nevertheless bread-making tests showed that the premixes formulations have better performance concerning the specific volume and the sensory characteristics. Statistical analysis confirmed that there is a significant difference in the specific volume and the sensory characteristics between the formulations, proving that the use of additives can enhance the quality of the French bread.

Implementation of Premixed Equilibrium Chemistry Capability in OVERFLOW

Science.gov (United States)

Olsen, Mike E.; Liu, Yen; Vinokur, M.; Olsen, Tom

2004-01-01

An implementation of premixed equilibrium chemistry has been completed for the OVERFLOW code, a chimera capable, complex geometry flow code widely used to predict transonic flowfields. The implementation builds on the computational efficiency and geometric generality of the solver.

[Recommendations for analgesia and sedation in neonatal intensive care].

Science.gov (United States)

Rawicz, Marcin

2008-01-01

The purpose of the study was to present recommendations, relevant to the management of neonates and infants aged 0-1 years, treated in intensive care settings. They include general principles and recommendations for pain and sedation assessment, sedation and pain management and advice on the use of pharmacological strategies. The bolus (on demand) administration of sedative agents should be avoided because of increased risk of cardiovascular depression and/or neurological complications. Midazolam administration time should be limited to 72 hours because of tachyphylaxis, and the possibility of development of a withdrawal syndrome and neurological complications (grade A, LOE 1b). The level of sedation and pain should be regularly assessed and documented, using presented scales; the COMFORT scale is preferred. Opioids, given in continuous infusion, are the drugs of choice for neonatal sedation. To avoid withdrawal syndrome, the total doses and time of administration of sedative agents should be limited. Methadone is a drug of choice in the treatment of a withdrawal (Grade B, LOE 2). Intravenous ketamine is recommended, when short-term sedation/anaesthesia is required (Grade C, LOE 3) for painful and/or stressful intensive care procedures. (Grade C, LOE 2). Muscle relaxants should be used for endotracheal intubation and in the situations when mechanical ventilation is not possible due to maximal respiratory effort of the patient.

[Analgesia and sedation in neonatal-pediatric intensive care].

Science.gov (United States)

Schlünder, C; Houben, F; Hartwig, S; Theisohn, M; Roth, B

1991-01-01

In pediatric intensive care, analgesia and sedation has become increasingly important for newborns as well as prematures in recent years. However, its importance is frequently not well recognized and sedation is confounded with analgesia. In our intensive-care unit (ICU), fentanyl and midazolam have proved to be useful. In newborn and premature infants, fentanyl alone has been sufficient because of its analgesic and sedative action. In a study on 20 newborns and prematures suffering from severe respiratory problems as compared with a historical group that did not receive fentanyl, we could show that in subjects receiving fentanyl, considerably less treatment with sedatives and other analgesics was necessary. Cardiopulmonary tolerance was satisfactory. The highest bilirubin values were reached about 1 day earlier and were slightly higher than those measured in the control group, but oral nutrition could be initiated sooner. In small infants, additional midazolam was given after cardiac surgery. During the first 72 h, we found a correlation between serum levels of midazolam and the depth of sedation; however, after 72 h of medication, the dose had to be raised because of an increase in metabolic clearance. During the concomitant administration of midazolam and fentanyl, significantly less midazolam was needed to achieve appropriate analog-sedation. Prior to the administration of analgesics and sedatives, care should be taken to ensure that circulatory conditions are stable and that there is no hypovolemia, and the drugs must be given slowly during several minutes. Especially in a pediatric ICU, light and noise should be diminished and contact between the parents and the child should be encouraged, even when the child is undergoing mechanical ventilation.

Direct Numerical Simulations of NOx formation in spatially developing turbulent premixed Bunsen flames with mixture inhomogeneity

KAUST Repository

Luca, Stefano

2017-01-05

Direct Numerical Simulation of three-dimensional spatially developing turbulent methane/air flames are performed. Four flames are simulated; they differ for the level of premixing of the fuel inlet: one has a fully premixed inlet, the other three have a partially premixed inlet that mimic a common injection strategy in stationary gas turbines. The jet consist of a methane/air mixture with global equivalence ratio ɸ = 0.7 and temperature of 800 K. The simulations are performed at 4 atm. The inlet velocity field and the fuel/air fields were extracted from a fully developed turbulent channel simulation. Chemistry is treated with a new skeletal chemical mechanism consisting of 33 species developed specifically for the DNS. The data are analyzed to study possible influences of partial premixing on the flame structure and the combustion efficiency. The results show that increasing the level of partial premixing, the fluctuations of heat release rate increase, due to the richer and leaner pockets of mixture in the flame, while the conditional mean decreases. Increasing the level of partial premixing, the peak of NO and the range of NO values for a given temperature increase. An analysis of NO production is performed categorizing the different initiation steps in the Ndecomposition through four pathways: thermal, prompt, NNH and NO. Different behaviour with respect to laminar flames is found for the NNH pathway suggesting that turbulence influences this pathway of formation of NO.

Techniques to administer oral, inhalational, and IV sedation in dentistry

Directory of Open Access Journals (Sweden)

Diana Krystyna Harbuz

2016-02-01

Full Text Available Background Sedation in dentistry is a controversial topic given the variety of opinions regarding its safe practice. Aims This article evaluates the various techniques used to administer sedation in dentistry and specific methods practiced to form a recommendation for clinicians. Methods An extensive literature search was performed using PubMed, Medline, Google Scholar, Google, and local library resources. Results Most of the literature revealed a consensus that light sedation on low-risk American Society of Anesthesiologists (ASA groups, that is ASA I, and possibly II, is the safest method for sedation in a dental outpatient setting. Conclusion Formal training is essential to achieve the safe practice of sedation in dentistry or medicine. The appropriate setting for sedation should be determined as there is an increased risk outside the hospital setting. Patients should be adequately assessed and medication titrated appropriately, based on individual requirements.

Experimental Investigation of Turbulence-Chemistry Interaction in High-Reynolds-Number Turbulent Partially Premixed Flames

Science.gov (United States)

2016-06-23

AFRL-AFOSR-VA-TR-2016-0277 Experimental Investigation of Turbulence-Chemistry Interaction in High- Reynolds -Number Turbulent Partially Premixed...4. TITLE AND SUBTITLE [U] Experimental investigation of turbulence-chemistry interaction in high- Reynolds -number 5a. CONTRACT NUMBER turbulent...for public release Final Report: Experimental investigation of turbulence-chemistry interaction in high- Reynolds -number turbulent partially premixed

Auditory processing during deep propofol sedation and recovery from unconsciousness.

Science.gov (United States)

Koelsch, Stefan; Heinke, Wolfgang; Sammler, Daniela; Olthoff, Derk

2006-08-01

Using evoked potentials, this study investigated effects of deep propofol sedation, and effects of recovery from unconsciousness, on the processing of auditory information with stimuli suited to elicit a physical MMN, and a (music-syntactic) ERAN. Levels of sedation were assessed using the Bispectral Index (BIS) and the Modified Observer's Assessment of Alertness and Sedation Scale (MOAAS). EEG-measurements were performed during wakefulness, deep propofol sedation (MOAAS 2-3, mean BIS=68), and a recovery period. Between deep sedation and recovery period, the infusion rate of propofol was increased to achieve unconsciousness (MOAAS 0-1, mean BIS=35); EEG measurements of recovery period were performed after subjects regained consciousness. During deep sedation, the physical MMN was markedly reduced, but still significant. No ERAN was observed in this level. A clear P3a was elicited during deep sedation by those deviants, which were task-relevant during the awake state. As soon as subjects regained consciousness during the recovery period, a normal MMN was elicited. By contrast, the P3a was absent in the recovery period, and the P3b was markedly reduced. Results indicate that the auditory sensory memory (as indexed by the physical MMN) is still active, although strongly reduced, during deep sedation (MOAAS 2-3). The presence of the P3a indicates that attention-related processes are still operating during this level. Processes of syntactic analysis appear to be abolished during deep sedation. After propofol-induced anesthesia, the auditory sensory memory appears to operate normal as soon as subjects regain consciousness, whereas the attention-related processes indexed by P3a and P3b are markedly impaired. Results inform about effects of sedative drugs on auditory and attention-related mechanisms. The findings are important because these mechanisms are prerequisites for auditory awareness, auditory learning and memory, as well as language perception during anesthesia.

Relieving existential suffering through palliative sedation: discussion of an uneasy practice.

Science.gov (United States)

Bruce, Anne; Boston, Patricia

2011-12-01

This article presents a discussion of the use of palliative sedation in response to intractable (not responsive to treatment) existential suffering. Patients suffering from a terminal illness are often faced with severe symptoms at the end of life. Although palliative sedation is sometimes used when no other options are effective in relieving unbearable pain or suffering, its use in response to intractable existential suffering in terminal illness remains controversial. A literature search was conducted for published articles addressing the use of palliative sedation between 1996 and 2009 using established databases. Palliative sedation remains an uneasy practice. The debates have centred on ethical issues surrounding decisions to use sedation and on separating the intent of palliative sedation (relief of intolerable symptoms) from the intent of euthanasia (hastening death). There is lack of consensus in defining existential suffering. Consequently, there is limited understanding of how decisions are being made when using palliative sedation to treat intractable existential suffering. Given the confusion and uncertainty about ethical and clinical justifications for palliative sedation in treating existential suffering, we argue that a better understanding of the controversies and decision-making process is needed. Greater understanding is required to prevent palliative sedation from becoming a substitute for intensive treatment of this kind of suffering. © 2011 Blackwell Publishing Ltd.

Sedation during bronchoscopy: data from a nationwide sedation and monitoring survey.

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Gaisl, Thomas; Bratton, Daniel J; Heuss, Ludwig T; Kohler, Malcolm; Schlatzer, Christian; Zalunardo, Marco P; Frey, Martin; Franzen, Daniel

2016-08-05

There is limited knowledge on practice patterns in procedural sedation and analgesia (PSA), the use of propofol, and monitoring during flexible bronchoscopy (FB). The purpose of this study was to assess the current practice patterns of FBs and to focus on the use of propofol, the education of the proceduralist, and the involvement of anaesthesiologists during FB. An anonymous questionnaire was sent to 299 pulmonologists. Only respondents who were active physicians in adult respiratory medicine performing FB were subsequently analysed. The response rate was 78 % and 27,149 FB in the previous 12 months were analysed. The overall sedation-related morbidity rate was 0.02 % and mortality was 7/100'000 FB. Sedation was used in 95 % of bronchoscopies. The main drugs used for PSA were propofol (77 %) and midazolam (46 %). In 84 % of PSAs propofol was used without the attendance of an anaesthesiologist. The use of propofol was associated with high volume bronchoscopists (p vital parameters has become standard practice, pulmonologists reported a very low rate of systematic basic education and training in the field of PSA (50 %). In Switzerland, PSA during FB is mostly performed with propofol without the attendance of an anaesthesiologist and the use of this drug is expected to increase in the future. While monitoring standards are very high there is need for policies to improve education, systematic training, and support for pulmonologists for PSA during FB.

Comparison of oral ketamine and oral midazolam as sedative agents in pediatric dentistry

Directory of Open Access Journals (Sweden)

Damle S

2008-09-01

Full Text Available The safe and effective treatment of uncooperative or combative preschool children with extensive dental needs is one of pediatric dentist′s ongoing challenges. The traditional methods of behavior management are no longer acceptable to parents as they are not ready to spare more time for dental treatment of their children. Keeping this in mind, the present study was designed and carried out to evaluate the sedative effects of oral ketamine and oral midazolam prior to general anesthesia. Twenty uncooperative children in the age-group of 2-6 years were selected after thorough medical examination and investigations. Informed consent was obtained from the parent. This was a randomized double-blind study. An anesthesiologist administered either 0.5 mg/kg midazolam or 5 mg/kg ketamine orally. The heart rate, respiratory rate, and oxygen saturation were recorded at regular intervals. The sedation and anxiolysis scores were also recorded. The parents were asked to answer a questionnaire at the follow-up session the next day on the surgical experience of the parent and the child and side effects experienced, if any. When the data was subjected to statistical analysis, it was observed that both drugs resulted in adequate sedation at the end of 30 min, with oral midazolam providing significantly better anxiolysis. The heart rate and respiratory rate were marginally higher with oral ketamine. The questionnaire revealed a better response with oral midazolam; side effects were more prominent with oral ketamine.

Sedation in the ICU Less is more

DEFF Research Database (Denmark)

Strom, T.

2012-01-01

. The intervention group received only bolus doses of morphine or haloperidol if delirium was suspected. The control group received standard infusion of sedatives to RAMSAY 3-4 and sedatives were interrupted on a daily basis. Both groups received morphine as intravenous bolus doses (2.5 to 5 mg). The primary outcome...

Direct numerical simulations of premixed autoignition in compressible uniformly-sheared turbulence

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Towery, Colin; Darragh, Ryan; Poludnenko, Alexei; Hamlington, Peter

2017-11-01

High-speed combustion systems, such as scramjet engines, operate at high temperatures and pressures, extremely short combustor residence times, very high rates of shear stress, and intense turbulent mixing. As a result, the reacting flow can be premixed and have highly-compressible turbulence fluctuations. We investigate the effects of compressible turbulence on the ignition delay time, heat-release-rate (HRR) intermittency, and mode of autoignition of premixed Hydrogen-air fuel in uniformly-sheared turbulence using new three-dimensional direct numerical simulations with a multi-step chemistry mechanism. We analyze autoignition in both the Eulerian and Lagrangian reference frames at eight different turbulence Mach numbers, Mat , spanning the quasi-isentropic, linear thermodynamic, and nonlinear compressibility regimes, with eddy shocklets appearing in the nonlinear regime. Results are compared to our previous study of premixed autoignition in isotropic turbulence at the same Mat and with a single-step reaction mechanism. This previous study found large decreases in delay times and large increases in HRR intermittency between the linear and nonlinear compressibility regimes and that detonation waves could form in both regimes.

Gravitational Influences on Flame Propagation through Non-Uniform, Premixed Gas Systems

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Miller, Fletcher J.; Easton, John; Ross, Howard D.; Marchese, Anthony; Perry, David; Kulis, Michael

2001-01-01

Flame propagation through non-uniformly premixed (or layered) gases has importance both in useful combustion systems and in unintentional fires. As summarized previously, non-uniform premixed gas combustion receives scant attention compared to the more usual limiting cases of diffusion or uniformly premixed flames, especially regarding the role gravity plays. This paper summarizes our progress on furthering the knowledge of layered combustion, in which a fuel concentration gradient exists normal to the direction of flame spread. We present experimental and numerical results for flame spread through propanol-air layers formed near the flash point temperature (25 C) or near the stoichiometric temperature (33 C). Both the model and experimental results show that the removal of gravity results in a faster spreading flame, by as much as 80% depending on conditions. This is exactly the opposite effect as that predicted by an earlier model reported. We also found that having a gallery lid results in faster flame spread, an effect more pronounced at normal gravity, demonstrating the importance of enclosure geometry. Also reported here is the beginning of our spectroscopic measurements of fuel vapor.

The interpersonal work of dental conscious sedation: A qualitative analysis.

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Woolley, Stephen M; Chadwick, Barbara; Pugsley, Lesley

2017-08-01

Whilst there is a considerable body of literature examining the pharmacology of conscious sedation, the social tasks required to successfully provide conscious sedation have not been reported. This paper discusses data regarding the interpersonal work integral to effective conscious sedation provision, from a larger qualitative study exploring how patients and clinicians engage with secondary care conscious sedation provided within the UK. Semi-structured interviews were conducted with 13 conscious sedation providers and nine patients within UK-based secondary care sedation settings. Digital audio-recordings were transcribed verbatim and subsequently analysed using a constant comparative method within NVivo Data Analysis Software. Four main themes of interpersonal work were reported by participants: displaying care, containing emotions, demonstrating competence and maximizing the effect. This study shows that performing conscious sedation requires more than technical delivery, and involves the projection of attributes in a literal "performance." The importance of managing outward emotional appearance reflects previous dental research. The need to manage outward appearance, and the emotional impact this has, is of relevance to all clinicians. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Intranasal dexmedetomidine for sedation for pediatric computed tomography imaging.

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Mekitarian Filho, Eduardo; Robinson, Fay; de Carvalho, Werther Brunow; Gilio, Alfredo Elias; Mason, Keira P

2015-05-01

This prospective observational pilot study evaluated the aerosolized intranasal route for dexmedetomidine as a safe, effective, and efficient option for infant and pediatric sedation for computed tomography imaging. The mean time to sedation was 13.4 minutes, with excellent image quality, no failed sedations, or significant adverse events. Registered with ClinicalTrials.gov: NCT01900405. Copyright © 2015 Elsevier Inc. All rights reserved.

Large Eddy Simulation of High-Speed, Premixed Ethylene Combustion

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Ramesh, Kiran; Edwards, Jack R.; Chelliah, Harsha; Goyne, Christopher; McDaniel, James; Rockwell, Robert; Kirik, Justin; Cutler, Andrew; Danehy, Paul

2015-01-01

A large-eddy simulation / Reynolds-averaged Navier-Stokes (LES/RANS) methodology is used to simulate premixed ethylene-air combustion in a model scramjet designed for dual mode operation and equipped with a cavity for flameholding. A 22-species reduced mechanism for ethylene-air combustion is employed, and the calculations are performed on a mesh containing 93 million cells. Fuel plumes injected at the isolator entrance are processed by the isolator shock train, yielding a premixed fuel-air mixture at an equivalence ratio of 0.42 at the cavity entrance plane. A premixed flame is anchored within the cavity and propagates toward the opposite wall. Near complete combustion of ethylene is obtained. The combustor is highly dynamic, exhibiting a large-scale oscillation in global heat release and mass flow rate with a period of about 2.8 ms. Maximum heat release occurs when the flame front reaches its most downstream extent, as the flame surface area is larger. Minimum heat release is associated with flame propagation toward the cavity and occurs through a reduction in core flow velocity that is correlated with an upstream movement of the shock train. Reasonable agreement between simulation results and available wall pressure, particle image velocimetry, and OH-PLIF data is obtained, but it is not yet clear whether the system-level oscillations seen in the calculations are actually present in the experiment.

Intention, procedure, outcome and personhood in palliative sedation and euthanasia.

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Materstvedt, Lars Johan

2012-03-01

Palliative sedation at the end of life has become an important last-resort treatment strategy for managing refractory symptoms as well as a topic of controversy within palliative care. Furthermore, palliative sedation is prominent in the public debate about the possible legalisation of voluntary assisted dying (physician-assisted suicide and euthanasia). This article attempts to demonstrate that palliative sedation is fundamentally different from euthanasia when it comes to intention, procedure, outcome and the status of the person. Nonetheless, palliative sedation in its most radical form of terminal deep sedation parallels euthanasia in one respect: both end the experience of suffering. However, only the latter intentionally ends life and also has this as its goal. There is the danger that deep sedation could bring death forward in time due to particular side effects of the treatment. Still that would, if it happens, not be intended, and accordingly is defensible in view of the doctrine of double effect.

Flemish palliative-care nurses' attitudes to palliative sedation: a quantitative study.

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Gielen, Joris; Van den Branden, Stef; Van Iersel, Trudie; Broeckaert, Bert

2012-09-01

Palliative sedation is an option of last resort to control refractory suffering. In order to better understand palliative-care nurses' attitudes to palliative sedation, an anonymous questionnaire was sent to all nurses (589) employed in palliative care in Flanders (Belgium). In all, 70.5% of the nurses (n = 415) responded. A large majority did not agree that euthanasia is preferable to palliative sedation, were against non-voluntary euthanasia in the case of a deeply and continuously sedated patient and considered it generally better not to administer artificial floods or fluids to such a patient. Two clusters were found: 58.5% belonged to the cluster of advocates of deep and continuous sedation and 41.5% belonged to the cluster of nurses restricting the application of deep and continuous sedation. These differences notwithstanding, overall the attitudes of the nurses are in accordance with the practice and policy of palliative sedation in Flemish palliative-care units.

Continuous palliative sedation for cancer and noncancer patients.

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Swart, Siebe J; Rietjens, Judith A C; van Zuylen, Lia; Zuurmond, Wouter W A; Perez, Roberto S G M; van der Maas, Paul J; van Delden, Johannes J M; van der Heide, Agnes

2012-02-01

Palliative care is often focused on cancer patients. Palliative sedation at the end of life is an intervention to address severe suffering in the last stage of life. To study the practice of continuous palliative sedation for both cancer and noncancer patients. In 2008, a structured questionnaire was sent to 1580 physicians regarding their last patient receiving continuous sedation until death. A total of 606 physicians (38%) filled out the questionnaire, of whom 370 (61%) reported on their last case of continuous sedation (cancer patients: n=282 [76%] and noncancer patients: n=88 [24%]). More often, noncancer patients were older, female, and not fully competent. Dyspnea (odds ratio [OR]=2.13; 95% confidence interval [CI]: 1.22, 3.72) and psychological exhaustion (OR=2.64; 95% CI: 1.26, 5.55) were more often a decisive indication for continuous sedation for these patients. A palliative care team was consulted less often for noncancer patients (OR=0.45; 95% CI: 0.21, 0.96). Also, preceding sedation, euthanasia was discussed less often with noncancer patients (OR=0.42; 95% CI: 0.24, 0.73), whereas their relatives more often initiated discussion about euthanasia than relatives of cancer patients (OR=3.75; 95% CI: 1.26, 11.20). The practice of continuous palliative sedation in patients dying of cancer differs from patients dying of other diseases. These differences seem to be related to the less predictable course of noncancer diseases, which may reduce physicians' awareness of the imminence of death. Increased attention to noncancer diseases in palliative care practice and research is, therefore, crucial as is more attention to the potential benefits of palliative care consultation. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Palliative sedation: from the family perspective.

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Vayne-Bossert, Petra; Zulian, Gilbert B

2013-12-01

Palliative sedation (PS) is a treatment option in case of refractory symptoms at the end of life. The emotional impact on nurses and doctors has been widely studied. We explore the experience of family members during a PS procedure. An anonymous questionnaire was sent to the closest family members (n = 17) of patients who died while receiving palliative sedation. The response rate was 59% (10 of 17). Nine relatives were sufficiently informed about PS. In all, 70% evaluated the chosen moment for initiation of PS as adequate. All the relatives noticed a significant improvement in the refractory symptom with a mean reduction in the estimated suffering of 6.25 points on a visual analog scale. Palliative sedation should be performed in the best possible way for the patient and his family in order to efficiently reduce a refractory symptom.

Palliative sedation at home in the Netherlands: a nationwide survey among nurses.

Science.gov (United States)

Brinkkemper, Tijn; Klinkenberg, Marianne; Deliens, Luc; Eliel, Miriam; Rietjens, Judith A C; Zuurmond, Wouter W A; Perez, Roberto S G M

2011-08-01

This paper is a report of a nationwide study conducted to assess experiences of nurses involved in palliative sedation at home after introduction of a physicians' guideline for palliative sedation. Most studies investigating the practice of palliative sedation focus on physicians' practices and attitudes. However, little is known about experiences and attitudes of nurses. A web-based structured questionnaire was offered to 387 nurses providing medical technical care in 2007, assessing their experiences concerning decision-making, treatment policy and communication, focussing on the last patient receiving palliative sedation. The questionnaire was filled out by 201 nurses (response rate 52%). The majority of respondents agreed with the indication for palliative sedation. However, 21% reported to have refused carrying out a palliative sedation in the preceding year. The general practitioner was not present at the start of palliative sedation in a third of the cases, but was available when needed. The sedation was considered insufficiently effective by 42% of the respondents. According to a third of the respondents, the level of sedation was not related to the required level of symptom relief nor were changes in dosage based on the severity of symptoms. Although the guideline for palliative sedation appears to be followed adequately in the majority of cases with respect to indication for palliative sedation and reportage. The survey findings revealed shortcomings in medication policy, communication, medical control over the start and continued monitoring of palliative sedation. © 2011 The Authors. Journal of Advanced Nursing © 2011 Blackwell Publishing Ltd.

Palliative sedation in end-of-life care and survival: a systematic review.

Science.gov (United States)

Maltoni, Marco; Scarpi, Emanuela; Rosati, Marta; Derni, Stefania; Fabbri, Laura; Martini, Francesca; Amadori, Dino; Nanni, Oriana

2012-04-20

Palliative sedation is a clinical procedure aimed at relieving refractory symptoms in patients with advanced cancer. It has been suggested that sedative drugs may shorten life, but few studies exist comparing the survival of sedated and nonsedated patients. We present a systematic review of literature on the clinical practice of palliative sedation to assess the effect, if any, on survival. A systematic review of literature published between January 1980 and December 2010 was performed using MEDLINE and EMBASE databases. Search terms included palliative sedation, terminal sedation, refractory symptoms, cancer, neoplasm, palliative care, terminally ill, end-of-life care, and survival. A manual search of the bibliographies of electronically identified articles was also performed. Eleven published articles were identified describing 1,807 consecutive patients in 10 retrospective or prospective nonrandomized studies, 621 (34.4%) of whom were sedated. One case-control study was excluded from prevalence analysis. The most frequent reason for sedation was delirium in the terminal stages of illness (median, 57.1%; range, 13.8% to 91.3%). Benzodiazepines were the most common drug category prescribed. Comparing survival of sedated and nonsedated patients, the sedation approach was not shown to be associated with worse survival. Even if there is no direct evidence from randomized clinical trials, palliative sedation, when appropriately indicated and correctly used to relieve unbearable suffering, does not seem to have any detrimental effect on survival of patients with terminal cancer. In this setting, palliative sedation is a medical intervention that must be considered as part of a continuum of palliative care.

The rate of adverse events during IV conscious sedation.

Science.gov (United States)

Schwamburger, Nathan T; Hancock, Raymond H; Chong, Chol H; Hartup, Grant R; Vandewalle, Kraig S

2012-01-01

Conscious sedation has become an integral part of dentistry; it is often used to reduce anxiety or fear in some patients during oral surgery, periodontal surgery, implant placement, and general dentistry procedures. The purpose of this study was to evaluate the frequency of adverse events during IV conscious sedation provided by credentialed general dentists and periodontists in the United States Air Force (USAF). Sedation clinical records (Air Force Form 1417) from calendar year 2009 were requested from all USAF bases. A total of 1,468 records were reviewed and 19 adverse events were noted in 17 patients. IV complication (infiltration) was the most common adverse event. The overall adverse event rate was 1.3 per 100 patients treated. The results of this study show that moderate sedation provided by general dentists and periodontists in the USAF has a low incidence of adverse events, and conscious sedation remains a viable option for providers for the reduction of anxiety in select patients.

[Sedation and analgesia practices among Spanish neonatal intensive care units].

Science.gov (United States)

Avila-Alvarez, A; Carbajal, R; Courtois, E; Pertega-Diaz, S; Muñiz-Garcia, J; Anand, K J S

2015-08-01

Pain management and sedation is a priority in neonatal intensive care units. A study was designed with the aim of determining current clinical practice as regards sedation and analgesia in neonatal intensive care units in Spain, as well as to identify factors associated with the use of sedative and analgesic drugs. A multicenter, observational, longitudinal and prospective study. Thirty neonatal units participated and included 468 neonates. Of these, 198 (42,3%) received sedatives or analgesics. A total of 19 different drugs were used during the study period, and the most used was fentanyl. Only fentanyl, midazolam, morphine and paracetamol were used in at least 20% of the neonates who received sedatives and/or analgesics. In infusions, 14 different drug prescriptions were used, with the most frequent being fentanyl and the combination of fentanyl and midazolam. The variables associated with receiving sedation and/or analgesia were, to have required invasive ventilation (P3 (P=.023; OR=2.26), the existence of pain evaluation guides in the unit (Pneonates admitted to intensive care units receive sedatives or analgesics. There is significant variation between Spanish neonatal units as regards sedation and analgesia prescribing. Our results provide evidence on the "state of the art", and could serve as the basis of preparing clinical practice guidelines at a national level. Copyright © 2015 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

[Use of sedation in the palliative care situation by respiratory physicians].

Science.gov (United States)

Grijol-Cariou, A-L; Goupil, F; Hubault, P; Jouanneau, J

2014-01-01

The prognosis of advanced stage chronic lung disease, including lung cancer, is often poor and associated with uncomfortable symptoms for the patient, especially in the end of life phase. In the case of intolerable symptoms, refractory to maximal treatment, sedation may then be considered. This is sometimes a source of confusion and difficulty for clinicians who need to know the official guidelines. The purpose of this study was to investigate the use of sedation by respiratory physicians, in order to understand their difficulties in these complex situations. The study was conducted using semi-structured, anonymous interviews of volunteers. The topics discussed included their definition of sedation, its indications, their possible difficulties or reluctance in using it, the information given to the patient and the traceability of the sedation prescription. All respiratory physicians agreed to participate in the study, indicating a major interest in this topic. No sedation decision is taken without careful consideration. The majority of physicians understand the difference between anxiolysis and sedation, most defining the latter as using a drug to sedate a patient faced with uncontrollable symptoms. All doctors refused to link sedation to euthanasia, although half expressed a feeling of causality between sedation and the patient's death - knowing that few consider the possibility of transient sedation. The main reluctance among doctors is in chronic respiratory insufficiency. Any decision concerning sedation should be discussed beforehand with the care team and the resident in charge of the patient, but not necessarily with another colleague. There is rarely evidence of this discussion in the medical records or of the information given to the patient and his family, thus increasing the difficulties of decision-making, especially at nights or weekends. The decision to start sedation is seen as difficult because it presupposes that a life-threatening short

Determination of appropriate models and parameters for premixing calculations

Energy Technology Data Exchange (ETDEWEB)

Park, Ik-Kyu; Kim, Jong-Hwan; Min, Beong-Tae; Hong, Seong-Wan

2008-03-15

The purpose of the present work is to use experiments that have been performed at Forschungszentrum Karlsruhe during about the last ten years for determining the most appropriate models and parameters for premixing calculations. The results of a QUEOS experiment are used to fix the parameters concerning heat transfer. The QUEOS experiments are especially suited for this purpose as they have been performed with small hot solid spheres. Therefore the area of heat exchange is known. With the heat transfer parameters fixed in this way, a PREMIX experiment is recalculated. These experiments have been performed with molten alumina (Al{sub 2}O{sub 3}) as a simulant of corium. Its initial temperature is 2600 K. With these experiments the models and parameters for jet and drop break-up are tested.

Determination of appropriate models and parameters for premixing calculations

International Nuclear Information System (INIS)

Park, Ik-Kyu; Kim, Jong-Hwan; Min, Beong-Tae; Hong, Seong-Wan

2008-03-01

The purpose of the present work is to use experiments that have been performed at Forschungszentrum Karlsruhe during about the last ten years for determining the most appropriate models and parameters for premixing calculations. The results of a QUEOS experiment are used to fix the parameters concerning heat transfer. The QUEOS experiments are especially suited for this purpose as they have been performed with small hot solid spheres. Therefore the area of heat exchange is known. With the heat transfer parameters fixed in this way, a PREMIX experiment is recalculated. These experiments have been performed with molten alumina (Al 2 O 3 ) as a simulant of corium. Its initial temperature is 2600 K. With these experiments the models and parameters for jet and drop break-up are tested

Partially premixed prevalorized kerosene spray combustion in turbulent flow

Energy Technology Data Exchange (ETDEWEB)

Chrigui, M.; Ahmadi, W.; Sadiki, A.; Janicka, J. [Institute for Energy and Powerplant Technology, TU Darmstadt, Petersenstr. 30, 64287 Darmstadt (Germany); Moesl, K. [Lehrstuhl fuer Thermodynamik, TU Muenchen, Boltzmannstr. 15, D-85747 Garching (Germany)

2010-04-15

A detailed numerical simulation of kerosene spray combustion was carried out on a partially premixed, prevaporized, three-dimensional configuration. The focus was on the flame temperature profile dependency on the length of the pre-vaporization zone. The results were analyzed and compared to experimental data. A fundamental study was performed to observe the temperature variation and flame flashback. Changes were made to the droplet diameter, kerosene flammability limits, a combustion model parameter and the location of the combustion initialization. Investigations were performed for atmospheric pressure, inlet air temperature of 90 C and a global equivalence ratio of 0.7. The simulations were carried out using the Eulerian Lagrangian procedure under a fully two-way coupling. The Bray-Moss-Libby model was adjusted to account for the partially premixed combustion. (author)

The early diagnosis and management of mixed delirium in a patient placed on ECMO and with difficult sedation: A case report.

Science.gov (United States)

Acevedo-Nuevo, María; González-Gil, Maria Teresa; Romera-Ortega, Miguel Ángel; Latorre-Marco, Ignacio; Rodríguez-Huerta, Maria Dolores

2018-02-01

Delirium represents a serious problem that impacts the physical and cognitive prognosis of patients admitted to intensive care units and requires prompt diagnosis and management. This article describes the case and progress of a patient placed on Extracorporeal Membrane Oxygenation with difficult sedation criteria and an early diagnosis of mixed delirium. During the case report, we reflect on the pharmacological and non-pharmacological strategies employed to cope with delirium paying special attention to the non-use of physical restraint measures in order to preserve vital support devices (endotracheal tube or Extracorporeal Membrane Oxygenation cannula). The multimodal and multidisciplinary approach, focused on nursing interventions, strict Pain/Agitation/Delirium monitoring and pharmacological measures, as well as the implementation of measures according to the eCASH (early Comfort using Analgesia, minimal Sedatives and maximal Human Care) concept, were effective, resulting in a relatively short admission considering the severity of the patient's condition and the associated complications. Early independent ambulation was achieved prior to transfer to a hospitalisation unit. Copyright © 2017 Elsevier Ltd. All rights reserved.

The sedative and analgesic potentials of dexmedtomidine ...

African Journals Online (AJOL)

Venous access was secured thirty minutes later, the fluid was connected to the cannula and was set to flow at daily fluid maintenance rate of 90mlkgday-1. Neither sedation nor analgesia was achieved with 20μgkg-1. Slight to moderate sedative effect was achieved at 40μg/kg with significant reduction in heart, pulse and ...

Applying Lean Techniques to Reduce Intravenous Waste Through Premixed Solutions and Increasing Production Frequency.

Science.gov (United States)

Lin, Alex C; Penm, Jonathan; Ivey, Marianne F; Deng, Yihong; Commins, Monica

This study aims to use lean techniques and evaluate the impact of increasing the use of premixed IV solutions and increased IV production frequency on IV waste. Study was conducted at a tertiary hospital pharmacy department in three phases. Phase I included evaluation of IV waste when IV production occurred three times a day and eight premixed IV products were used. Phase II increased the number of premixed IV products to 16. Phase III then increased IV production to five times a day. During Phase I, an estimate of 2,673 IV doses were wasted monthly, accounting for 6.14% of overall IV doses. This accounted for 688 L that cost $60,135. During Phase II, the average monthly IV wastage reduced significantly to 1,069 doses (2.84%), accounting for 447 L and $34,003. During Phase III, the average monthly IV wastage was further decreased to 675 doses (1.69%), accounting for 78 L and $3,431. Hence, a potential annual saving of $449,208 could result from these changes. IV waste was reduced through the increased use of premixed solutions and increasing IV production frequency.

Acute toxicity study of Vilocym Premix (herbal growth promoter for Livestockin Wistar Albino Rat

Directory of Open Access Journals (Sweden)

A.H. Ahmad

2009-06-01

Full Text Available An experimental study with the objective of safety evaluation of Vilocym Premix, herbal growth promoter for Livestock (supplied by Ayurvet Ltd., Baddi, India, was done as per standard guidelines of OECD-423 for acute toxicity testing. Vilocym Premix is a scientifically developed combination of herbs that contains herbal ingredients namely Azadirachta indica, Curcuma longa & many more alongwith natural zeolites. The study was done in 3 males and 3 female Wistar Albino rats, which were administered an initial dose of 50 mg/kg body weight followed by dose rates of 300, 500 & 5000 mg/kg body weight of test compound. The animals were observed for signs of convulsions, tremors, circling, depression, excitement and mortality. Body weight was recorded at 0,7th and 14th day and plasma total protein, albumin; AST and ALT were measured after 3rd day of experiment. No abnormal sign of symptoms were observed in any of the animal fed with Vilocym Premix at the dose rate of 50, 300, 500 & 5000 mg/kg. No mortality was observed indicating safety of herbal premix. [Vet. World 2009; 2(3.000: 100-102

Chloral hydrate sedation in radiology: retrospective audit of reduced dose

Energy Technology Data Exchange (ETDEWEB)

Bracken, Jennifer [Children' s University Hospital, Radiology Department, Dublin (Ireland); Royal Children' s Hospital, Department of Medical Imaging, Parkville, Victoria (Australia); Heaslip, Ingrid; Ryan, Stephanie [Children' s University Hospital, Radiology Department, Dublin (Ireland)

2012-03-15

Chloral hydrate (CH) is safe and effective for sedation of suitable children. The purpose of this study was to assess whether adequate sedation is achieved with reduced CH doses. We retrospectively recorded outpatient CH sedations over 1 year. We defined standard doses of CH as 50 mg/kg (infants) and 75 mg/kg (children >1 year). A reduced dose was defined as at least 20% lower than the standard dose. In total, 653 children received CH sedation (age, 1 month-3 years 10 months), 42% were given a reduced initial dose. Augmentation dose was required in 10.9% of all children, and in a higher proportion of children >1 year (15.7%) compared to infants (5.7%; P < 0.001). Sedation was successful in 96.7%, and more frequently successful in infants (98.3%) than children >1 year (95.3%; P = 0.03). A reduced initial dose had no negative effect on outcome (P = 0.19) or time to sedation. No significant complications were seen. We advocate sedation with reduced CH doses (40 mg/kg for infants; 60 mg/kg for children >1 year of age) for outpatient imaging procedures when the child is judged to be quiet or sleepy on arrival. (orig.)

Review of palliative sedation and its distinction from euthanasia and lethal injection.

Science.gov (United States)

Hahn, Michael P

2012-01-01

Palliative sedation evolved from within the practice of palliative medicine and has become adopted by other areas of medicine, such as within intensive care practice. Clinician's usually come across this practice for dying patients who are foregoing or having life support terminated. A number of intolerable and intractable symptom burdens can occur during the end of life period that may require the use of palliative sedation. Furthermore, when patients receive palliative sedation, the continued use of hydration and nutrition becomes an issue of consideration and there are contentious bioethical issues involved in using or withholding these life-sustaining provisions. A general understanding of biomedical ethics helps prevent abuse in the practice of palliative sedation. Various sedative drugs can be employed in the provision of palliative sedation that can produce any desired effect, from light sedation to complete unconsciousness. Although there are some similarities in the pharmacotherapy of palliative sedation, euthanasia, physician-assisted suicide, and lethal injection, there is a difference in how the drugs are administered with each practice. There are some published guidelines about how palliative sedation should be practiced, but currently there is not any universally accepted standard of practice.

Sedative load and salivary secretion and xerostomia in community-dwelling older people.

Science.gov (United States)

Tiisanoja, Antti; Syrjälä, Anna-Maija; Komulainen, Kaija; Hartikainen, Sirpa; Taipale, Heidi; Knuuttila, Matti; Ylöstalo, Pekka

2016-06-01

The aim was to investigate how sedative load and the total number of drugs used are related to hyposalivation and xerostomia among 75-year-old or older dentate, non-smoking, community-dwelling people. The study population consisted of 152 older people from the Oral Health GeMS study. The data were collected by interviews and clinical examinations during 2004-2005. Sedative load, which measures the cumulative effect of taking multiple drugs with sedative properties, was calculated using the Sedative Load Model. The results showed that participants with a sedative load of either 1-2 or ≥3 had an increased likelihood of having low stimulated salivary flow (xerostomia (OR: 2.5, CI: 0.5-12) compared with participants without a sedative load. The results showed that the association between the total number of drugs and hyposalivation was weaker than the association between sedative load and hyposalivation. Sedative load is strongly related to hyposalivation and to a lesser extent with xerostomia. The adverse effects of drugs on saliva secretion are specifically related to drugs with sedative properties. © 2014 John Wiley & Sons A/S and The Gerodontology Association. Published by John Wiley & Sons Ltd.

A randomized controlled trial to compare fentanyl-propofol and ketamine-propofol combination for procedural sedation and analgesia in laparoscopic tubal ligation

Directory of Open Access Journals (Sweden)

Ranju Singh

2013-01-01

Full Text Available Background: Procedural sedation and analgesia is widely being used for female laparoscopic sterilization using combinations of different drugs at varying doses. This study compared the combination of fentanyl and propofol, and ketamine and propofol in patients undergoing outpatient laparoscopic tubal ligation, with respect to their hemodynamic effects, postoperative recovery characteristics, duration of hospital stay, adverse effects, and patient comfort and acceptability. Settings and Design: Randomized, double blind. Methods: Patients were assigned to receive premixed injection of either fentanyl 1.5 μg/kg + propofol 2 mg/kg (Group PF, n0=50 or ketamine 0.5 mg/kg + propofol 2 mg/kg (Group PK, n=50. Hemodynamic data, peripheral oxygen saturation, and respiratory rate were recorded perioperatively. Recovery time, time to discharge, and comfort score were noted. Statistical Analysis: Chi-square (χ2 test was used for categorical data. Student′s t-test was used for quantitative variables for comparison between the two groups. For intragroup comparison, paired t-test was used. SPSS 14.0 was used for analysis. Results: Although the heart rate was comparable, blood pressures were consistently higher in group PK. Postoperative nausea and vomiting and delay in voiding were more frequent in group PK ( P<0.05. The time to reach Aldrete score ≥8 was significantly longer in group PK (11.14±3.29 min in group PF vs. 17.3±6.32 min in group PK, P<0.01. The time to discharge was significantly longer in group PK (105.8±13.07 min in group PF vs.138.18±13.20 min in group PK, P<0.01. Patient comfort and acceptability was better in group PF, P<0.01. Conclusion: As compared to ketamine-propofol, fentanyl-propofol combination is associated with faster recovery, earlier discharge, and better patient acceptability.

Propofol Effect on Stress Response and Free Radicals in Patient during Surgery and Sedation Procedure

Directory of Open Access Journals (Sweden)

Theresia Monica Rahardjo

2015-12-01

Full Text Available BACKGROUND: Propofol is an intravenous anesthetic used worldwide as an anesthesia induction and maintenance agent. Propofol also used as sedation agent in Intensive Care Unit (ICU. Despite it’s usual anesthesia properties, propofol has an unique pharmacologic characteristic, especially as antioxidant and stress response reduction. These advantages suggested propofol has positive effects when used as an anesthesia agent in surgery or sedation in ICU in conditions when high stress and free radical level are released. CONTENT: Stress response and free radical can be elevated in various conditions including surgery or during care in ICU, especially critical ill patient. Cortisol is a major stress hormone that influences metabolism, cardiovascular and central nervous system, either in acute or chronic phase. Oxidative stress was marked by free radical elevation called Radical Oxygen Species (ROS. Combination of both elements (cortisol and ROS can worsen patient condition. Propofol with anti-stress and antioxidant properties could be used to reduce stress response and attenuate free radical level in order to improve patient condition. SUMMARY: The anti-stress and antioxidant properties of Propofol are interesting, because these benefits can be added as adjunctive therapy when propofol was used as an anesthetic agent in surgery and a sedation in ICU. KEYWORDS: propofol, stress response, antioxidant.

Palliative sedation: a focus group study on the experiences of relatives.

Science.gov (United States)

Bruinsma, Sophie; Rietjens, Judith; van der Heide, Agnes

2013-04-01

Most studies that have investigated the practice of palliative sedation have focused on physicians' practices and attitudes. The aim of this study was to explore relatives' experiences with palliative sedation and to gain more insight in positive and negative elements in their evaluation of palliative sedation. Focus groups and individual interviews. Various care settings in the Netherlands. A total of 14 relatives of patients who received palliative sedation until death participated. Most relatives evaluated the provision of palliative sedation of their dying family member positively. Positive experiences were related to: the beneficial impact of palliative sedation on the patient's suffering, the opportunity that was offered to prepare for the patient's death, their involvement in the decision-making and care for the patient, and the pleasant care environment. However, the majority of the relatives were unsatisfied with one or more aspects of how information was being provided for. Some relatives were frustrated about the fact that nurses were not authorized to make decisions about the care for the patient and about the absence of physicians during weekends. None of the relatives mentioned the loss of the ability to communicate with the patient during the sedation and the possibility of "hastening death" as disadvantages of palliative sedation. Relatives tend to evaluate the provision of palliative sedation to their severely suffering family member positively because it contributes to a peaceful dying process. However, relatives indicated discontent with how information was being provided and with the communication in general.

Sedative medications outside the operating room and the pharmacology of sedatives

DEFF Research Database (Denmark)

Hansen, Tom G

2015-01-01

PURPOSE OF REVIEW: There is a growing medical demand for suitable sedatives and analgesics to support the ongoing progress in diagnostic procedures and imaging techniques. This review provides an update of the pharmacology of the most commonly used drugs used for these procedures and shortly...

On the regimes of premixing

Energy Technology Data Exchange (ETDEWEB)

Angelini, S.; Theofanous, T.G.; Yuen, W.W. [California Univ., Santa Barbara, CA (United States). Center for Risk Studies and Safety

1998-01-01

The conditions of the MAGICO-2000 experiment are extended to more broadly investigate the regimes of premixing, and the corresponding internal structures of mixing zones. With the help of the data and numerical simulations using the computer code PM-ALPHA, we can distinguish extremes of behavior dominated by inertia and thermal effects - we name these the inertia and thermal regimes, respectively. This is an important distinction that should guide future experiments aimed at code verification in this area. Interesting intermediate behaviors are also delineated and discussed. (author)

Randomised clinical trial: a 'nudge' strategy to modify endoscopic sedation practice.

Science.gov (United States)

Harewood, G C; Clancy, K; Engela, J; Abdulrahim, M; Lohan, K; O'Reilly, C

2011-07-01

In behavioural economics, a 'nudge' describes configuration of a choice to encourage a certain action without taking away freedom of choice. To determine the impact of a 'nudge' strategy - prefilling either 3mL or 5mL syringes with midazolam - on endoscopic sedation practice. Consecutive patients undergoing sedation for EGD or colonoscopy were enrolled. On alternate weeks, midazolam was prefilled in either 3mL or 5mL syringes. Preprocedure sedation was administered by the endoscopist to achieve moderate conscious sedation; dosages were at the discretion of the endoscopist. Meperidine was not prefilled. Overall, 120 patients received sedation for EGD [59 (5mL), 61 (3mL)] and 86 patients were sedated for colonoscopy [38 (5mL), 48 (3mL)]. For EGDs, average midazolam dose was significantly higher in the 5-mL group (5.2mg) vs. 3-mL group (3.3mg), (Pnudge' strategies may hold promise in modifying endoscopic sedation practice. Further research is required to explore the utility of 'nudges' in impacting other aspects of endoscopic practice. © 2011 Blackwell Publishing Ltd.

Considerations of physicians about the depth of palliative sedation at the end of life

Science.gov (United States)

Swart, Siebe J.; van der Heide, Agnes; van Zuylen, Lia; Perez, Roberto S.G.M.; Zuurmond, Wouter W.A.; van der Maas, Paul J.; van Delden, Johannes J.M.; Rietjens, Judith A.C.

2012-01-01

Background: Although guidelines advise titration of palliative sedation at the end of life, in practice the depth of sedation can range from mild to deep. We investigated physicians’ considerations about the depth of continuous sedation. Methods: We performed a qualitative study in which 54 physicians underwent semistructured interviewing about the last patient for whom they had been responsible for providing continuous palliative sedation. We also asked about their practices and general attitudes toward sedation. Results: We found two approaches toward the depth of continuous sedation: starting with mild sedation and only increasing the depth if necessary, and deep sedation right from the start. Physicians described similar determinants for both approaches, including titration of sedatives to the relief of refractory symptoms, patient preferences, wishes of relatives, expert advice and esthetic consequences of the sedation. However, physicians who preferred starting with mild sedation emphasized being guided by the patient’s condition and response, and physicians who preferred starting with deep sedation emphasized ensuring that relief of suffering would be maintained. Physicians who preferred each approach also expressed different perspectives about whether patient communication was important and whether waking up after sedation is started was problematic. Interpretation: Physicians who choose either mild or deep sedation appear to be guided by the same objective of delivering sedation in proportion to the relief of refractory symptoms, as well as other needs of patients and their families. This suggests that proportionality should be seen as a multidimensional notion that can result in different approaches toward the depth of sedation. PMID:22331961

Monitoring sedation status over time in ICU patients: reliability and validity of the Richmond Agitation-Sedation Scale (RASS).

Science.gov (United States)

Ely, E Wesley; Truman, Brenda; Shintani, Ayumi; Thomason, Jason W W; Wheeler, Arthur P; Gordon, Sharon; Francis, Joseph; Speroff, Theodore; Gautam, Shiva; Margolin, Richard; Sessler, Curtis N; Dittus, Robert S; Bernard, Gordon R

2003-06-11

Goal-directed delivery of sedative and analgesic medications is recommended as standard care in intensive care units (ICUs) because of the impact these medications have on ventilator weaning and ICU length of stay, but few of the available sedation scales have been appropriately tested for reliability and validity. To test the reliability and validity of the Richmond Agitation-Sedation Scale (RASS). Prospective cohort study. Adult medical and coronary ICUs of a university-based medical center. Thirty-eight medical ICU patients enrolled for reliability testing (46% receiving mechanical ventilation) from July 21, 1999, to September 7, 1999, and an independent cohort of 275 patients receiving mechanical ventilation were enrolled for validity testing from February 1, 2000, to May 3, 2001. Interrater reliability of the RASS, Glasgow Coma Scale (GCS), and Ramsay Scale (RS); validity of the RASS correlated with reference standard ratings, assessments of content of consciousness, GCS scores, doses of sedatives and analgesics, and bispectral electroencephalography. In 290-paired observations by nurses, results of both the RASS and RS demonstrated excellent interrater reliability (weighted kappa, 0.91 and 0.94, respectively), which were both superior to the GCS (weighted kappa, 0.64; P<.001 for both comparisons). Criterion validity was tested in 411-paired observations in the first 96 patients of the validation cohort, in whom the RASS showed significant differences between levels of consciousness (P<.001 for all) and correctly identified fluctuations within patients over time (P<.001). In addition, 5 methods were used to test the construct validity of the RASS, including correlation with an attention screening examination (r = 0.78, P<.001), GCS scores (r = 0.91, P<.001), quantity of different psychoactive medication dosages 8 hours prior to assessment (eg, lorazepam: r = - 0.31, P<.001), successful extubation (P =.07), and bispectral electroencephalography (r = 0.63, P

Risk and safety of pediatric sedation/anesthesia for procedures outside the operating room.

Science.gov (United States)

Cravero, Joseph P

2009-08-01

Sedation and anesthesia outside the operating room represents a rapidly growing field of practice that involves a number of different specialty providers including anesthesiology. The literature surrounding this work is found in a variety of journals - many outside anesthesiology. This review is intended to inform readers about the current status of risk and safety involving sedation/anesthesia for tests and minor procedures utilizing a wide range of sources. Two large database studies have helped to define the frequency and nature of adverse events in pediatric sedation/anesthesia practice from a multispecialty perspective. A number of papers describing respiratory and hemodynamic aspects of dexmedetomidine sedation have also been published. Finally, a number of studies relating to training sedation providers, reporting of sedation adverse events, sedation for vulnerable populations, and (in particular) ketamine sedation adverse respiratory events have also come to light. The latest publications continue to document a relatively low risk to pediatric sedation yet also warn us about the potential adverse events in this field. The results help to define competencies required to deliver pediatric sedation and make this practice even safer. Particularly interesting are new jargon and methodologies for defining adverse events and the use of new methods for training sedation providers.

An experimental study of the structure of laminar premixed flames of ethanol/methane/oxygen/argon

Science.gov (United States)

Tran, L.S.; Glaude, P.A.; Battin-Leclerc, F.

2013-01-01

The structures of three laminar premixed stoichiometric flames at low pressure (6.7 kPa): a pure methane flame, a pure ethanol flame and a methane flame doped by 30% of ethanol, have been investigated and compared. The results consist of concentration profiles of methane, ethanol, O2, Ar, CO, CO2, H2O, H2, C2H6, C2H4, C2H2, C3H8, C3H6, p-C3H4, a-C3H4, CH2O, CH3HCO, measured as a function of the height above the burner by probe sampling followed by on-line gas chromatography analyses. Flame temperature profiles have been also obtained using a PtRh (6%)-PtRh (30%) type B thermocouple. The similarities and differences between the three flames were analyzed. The results show that, in these three flames, the concentration of the C2 intermediates is much larger than that of the C3 species. In general, mole fraction of all intermediate species in the pure ethanol flame is the largest, followed by the doped flame, and finally the pure methane flame. PMID:24092946

Vortex combustor for low NOX emissions when burning lean premixed high hydrogen content fuel

Science.gov (United States)

Steele, Robert C; Edmonds, Ryan G; Williams, Joseph T; Baldwin, Stephen P

2012-11-20

A trapped vortex combustor. The trapped vortex combustor is configured for receiving a lean premixed gaseous fuel and oxidant stream, where the fuel includes hydrogen gas. The trapped vortex combustor is configured to receive the lean premixed fuel and oxidant stream at a velocity which significantly exceeds combustion flame speed in a selected lean premixed fuel and oxidant mixture. The combustor is configured to operate at relatively high bulk fluid velocities while maintaining stable combustion, and low NOx emissions. The combustor is useful in gas turbines in a process of burning synfuels, as it offers the opportunity to avoid use of diluent gas to reduce combustion temperatures. The combustor also offers the possibility of avoiding the use of selected catalytic reaction units for removal of oxides of nitrogen from combustion gases exiting a gas turbine.

The conditional moment closure method for modeling lean premixed turbulent combustion

Science.gov (United States)

Martin, Scott Montgomery

Natural gas fired lean premixed gas turbines have become the method of choice for new power generation systems due to their high efficiency and low pollutant emissions. As emission regulations for these combustion systems become more stringent, the use of numerical modeling has become an important a priori tool in designing clean and efficient combustors. Here a new turbulent combustion model is developed in an attempt to improve the state of the art. The Conditional Moment Closure (CMC) method is a new theory that has been applied to non-premixed combustion with good success. The application of the CMC method to premixed systems has been proposed, but has not yet been done. The premixed CMC method replaces the species mass fractions as independent variables with the species mass fractions that are conditioned on a reaction progress variable (RPV). Conservation equations for these new variables are then derived and solved. The general idea behind the CMC method is that the behavior of the chemical species is closely coupled to the reaction progress variable. Thus, species conservation equations that are conditioned on the RPV will have terms involving the fluctuating quantities that are much more likely to be negligible. The CMC method accounts for the interaction between scalar dissipation (micromixing) and chemistry, while de-coupling the kinetics from the bulk flow (macromixing). Here the CMC method is combined with a commercial computational fluid dynamics program, which calculates the large-scale fluid motions. The CMC model is validated by comparison to 2-D reacting backward facing step data. Predicted species, temperature and velocity fields are compared to experimental data with good success. The CMC model is also validated against the University of Washington's 3-D jet stirred reactor (JSR) data, which is an idealized lean premixed combustor. The JSR results are encouraging, but not as good as the backward facing step. The largest source of error is from

Spectral entropy as a monitor of depth of propofol induced sedation.

LENUS (Irish Health Repository)

Mahon, Padraig

2012-02-03

OBJECTIVE: The aim of this prospective, observational study was to evaluate State and Response entropy (Entropy(TM) Monitor, GE Healthcare, Finland), indices as measures of moderate ("conscious") sedation in healthy adult patients receiving a low dose propofol infusion. Sedation was evaluated using: (I) the responsiveness component of the OAA\\/S scale (Observer\\'s Assessment of Alertness\\/Sedation scale) and (II) multi-channel electroencephalogram (EEG) interpretation by a clinical expert. METHODS: 12 ASA I patients were recruited. A target-controlled infusion of propofol was administered (using Schnider\\'s pharmacokinetic model) with an initial effect site concentration set to 0.5 microg ml(-1). A 4 minute equilibrium period was allowed. This concentration was increased at 4 minute intervals by 0.5 microg ml(-1) to a maximum of 2.0 microg ml(-1). State (SE) and Response (RE), entropy values were recorded for each 4 minute epoch together with clinical sedation scores (OAA\\/S) and continuous multi-channel EEG. The multi-channel EEG recorded during the final minute of each 4 minute epoch or "patient\\/time unit" was presented to a neurophysiologist who assigned a label "sedated\\/not sedated". SE\\/RE values were compared in patient\\/time units with clinical or EEG evidence of sedation versus those without. RESULTS: Mean SE and RE values were less in patient\\/time units when clinical evidence of sedation was present, [mean = 86.8 (95% CI, 84.0-88.3) and 94.3 (95%CI, 92-96.1)], P = 0.002 and P = 0.001, respectively. In patient\\/time units assigned the label "sedated" by the clinical neurophysiologist assessing the multi-channel EEG, SE and RE values were less [mean = 87.5 (95% CI, 86.3-88.4) and 95.0 (95% CI, 93.8-96.1)] P = 0.001 and P < 0.001, respectively. CONCLUSIONS: A statistically significant decrease in SE and RE values was demonstrated in patient\\/time units in which clinical or EEG evidence of sedation was present. We conclude that spectral entropy

Continuous Palliative Sedation for Cancer and Noncancer Patients

NARCIS (Netherlands)

Swart, S.J.; Rietjens, J.A.C.; van Zuylen, L.; Zuurmond, W.W.A.; Perez, R.S.G.M.; van der Maas, P.J.; van Delden, J.J.M.; van der Heide, A.

2012-01-01

Context: Palliative care is often focused on cancer patients. Palliative sedation at the end of life is an intervention to address severe suffering in the last stage of life. Objectives: To study the practice of continuous palliative sedation for both cancer and noncancer patients. Methods: In 2008,

Experimental study of flame stability in biogas premix system

International Nuclear Information System (INIS)

Diaz G, Carlos A; Amell A Andres; Cardona Luis F

2008-01-01

Utilization of new renewable energy sources have had a special interest in last years looking for decrease the dependence of fossil fuels and the environmental impact generated for them. This work studies experimentally the flame stability of a simulated biogas with a volumetric composition of 60% methane and 40% carbon dioxide. The objective of this study is to obtain information about design and interchangeability of gases in premixed combustion systems that operate with different fuel gases. The critical velocity gradient was the stability criteria used. Utilization of this criteria and the experimental method followed, using a partial premixed burner, stability flame diagram of biogas studied had been obtained. Presence of carbon dioxide has a negative effect in flame stability, decreasing significantly the laminar flame speed and consequently, the stability range of biogas burners because of apparition of blow off.

Opinions of the Dutch public on palliative sedation: a mixed-methods approach.

Science.gov (United States)

van der Kallen, Hilde T H; Raijmakers, Natasja J H; Rietjens, Judith A C; van der Male, Alex A; Bueving, Herman J; van Delden, Johannes J M; van der Heide, Agnes

2013-10-01

Palliative sedation is defined as deliberately lowering a patient's consciousness, to relieve intolerable suffering from refractory symptoms at the end of life. Palliative sedation is considered a last resort intervention in end-of-life care that should not be confused with euthanasia. To inform healthcare professionals about attitudes of the general public regarding palliative sedation. design and setting: A cross-sectional survey among members of the Dutch general public followed by qualitative interviews. One thousand nine hundred and sixty members of the general public completed the questionnaire, which included a vignette describing palliative sedation (response rate 78%); 16 participants were interviewed. In total, 22% of the responders indicated knowing the term 'palliative sedation'. Qualitative data showed a variety of interpretations of the term. Eighty-one per cent of the responders agreed with the provision of sedatives as described in a vignette of a patient with untreatable pain and a life expectancy of sedatives to alleviate his suffering. This percentage was somewhat lower for a patient with a life expectancy of sedatives with the aim of ending the patient's life (79%, P = 0.54). Most of the general public accept the use of palliative sedation at the end of life, regardless of a potential life-shortening effect. However, confusion exists about what palliative sedation represents. This should be taken into account by healthcare professionals when communicating with patients and their relatives on end-of-life care options.

Pediatrician Ambiguity in Understanding Palliative Sedation at the End of Life.

Science.gov (United States)

Henderson, Carrie M; FitzGerald, Michael; Hoehn, K Sarah; Weidner, Norbert

2017-02-01

Palliative sedation is a means of relieving intractable symptoms at the end of life, however, guidelines about its use lack consistency. In addition, ethical concerns persist around the practice. There are reports of palliative sedation in the pediatric literature, which highlight various institutional perspectives. This survey of 4786 pediatric providers sought to describe their knowledge of and current practices around pediatric palliative sedation. Our survey was administered to pediatricians who care for children at the end of life. The survey assessed agreement with a definition of palliative sedation, as well as thoughts about its alignment with aggressive symptom management. Bivariate analyses using χ 2 and analysis of variance were calculated to determine the relationship between responses to closed-ended questions. Open-ended responses were thematically coded by the investigators and reviewed for agreement. Nearly half (48.6%) of the respondents indicated that the stated definition of palliative sedation "completely" reflected their own views. Respondents were split when asked if they viewed any difference between palliative sedation and aggressive symptom management: Yes (46%) versus No (54%). Open-ended responses revealed specifics about the nature of variation in interpretation. Responses point to ambiguity surrounding the concept of palliative sedation. Pediatricians were concerned with a decreased level of consciousness as the goal of palliative sedation. Respondents were split on whether they view palliative sedation as a distinct entity or as one broad continuum of care, equivalent to aggressive symptom management. Institutional-based policies are essential to clarify acceptable practice, enable open communication, and promote further research.

Randomised clinical trial: a 'nudge' strategy to modify endoscopic sedation practice.

LENUS (Irish Health Repository)

Harewood, G C

2012-02-01

BACKGROUND: In behavioural economics, a \\'nudge\\' describes configuration of a choice to encourage a certain action without taking away freedom of choice. AIM: To determine the impact of a \\'nudge\\' strategy - prefilling either 3mL or 5mL syringes with midazolam - on endoscopic sedation practice. METHODS: Consecutive patients undergoing sedation for EGD or colonoscopy were enrolled. On alternate weeks, midazolam was prefilled in either 3mL or 5mL syringes. Preprocedure sedation was administered by the endoscopist to achieve moderate conscious sedation; dosages were at the discretion of the endoscopist. Meperidine was not prefilled. RESULTS: Overall, 120 patients received sedation for EGD [59 (5mL), 61 (3mL)] and 86 patients were sedated for colonoscopy [38 (5mL), 48 (3mL)]. For EGDs, average midazolam dose was significantly higher in the 5-mL group (5.2mg) vs. 3-mL group (3.3mg), (P<0.0001); for colonoscopies, average midazolam dose was also significantly higher in the 5-mL group (5.1mg) vs. 3-mL group (3.3mg), (P<0.0001). There was no significant difference in mean meperidine dose (42.1mg vs. 42.8mg, P=0.9) administered to both colonoscopy groups. No adverse sedation-related events occurred; no patient required reversal of sedation. CONCLUSIONS: These findings demonstrate that \\'nudge\\' strategies may hold promise in modifying endoscopic sedation practice. Further research is required to explore the utility of \\'nudges\\' in impacting other aspects of endoscopic practice.

Current debates on end-of-life sedation: an international expert elicitation study.

Science.gov (United States)

Papavasiliou, Evangelia Evie; Payne, Sheila; Brearley, Sarah

2014-08-01

End-of-life sedation, though increasingly prevalent and widespread internationally, remains one of the most highly debated medical practices in the context of palliative medicine. This qualitative study aims to elicit and record the perspectives of leading international palliative care experts on current debates. Twenty-one professionals from diverse backgrounds, sharing field-specific knowledge/expertise defined by significant scholarly contribution on end-of-life sedation, were recruited. Open-ended, semi-structured interviews, following a topic-oriented structure reflecting on current debates, were conducted. Results were analysed using thematic content analysis. Three main aspects of sedation were identified and discussed as potentially problematic: (a) continuous deep sedation as an extreme facet of end-of-life sedation, (b) psycho-existential suffering as an ambivalent indication for sedation and (c) withdrawal or withholding of artificial nutrition and hydration as potentially life-shortening. On these grounds, concerns were reported over end-of-life sedation being morally equivalent to euthanasia. Considerable emphasis was placed on intentions as the distinguishing factor between end-of-life acts, and protective safeguards were introduced to distance sedation from euthanasia. This study shows that, despite the safeguards introduced, certain aspects of sedation, including the intentions associated with the practice, are still under question, parallels being drawn between end-of-life sedation and euthanasia. This reaffirms the existence of a grey area surrounding the two practices, already evidenced in countries where euthanasia is legalized. More clarity over the issues that generate this grey area, with their causes being uncovered and eliminated, is imperative to resolve current debates and effectively inform research, policy and practice of end-of-life sedation.

Update on dexmedetomidine: use in nonintubated patients requiring sedation for surgical procedures

Directory of Open Access Journals (Sweden)

Mohanad Shukry

2010-03-01

Full Text Available Mohanad Shukry, Jeffrey A MillerUniversity of Oklahoma Health Sciences Center, Department of Anesthesiology, Children’s Hospital of Oklahoma, Oklahoma City, OK, USAAbstract: Dexmedetomidine was introduced two decades ago as a sedative and supplement to sedation in the intensive care unit for patients whose trachea was intubated. However, since that time dexmedetomidine has been commonly used as a sedative and hypnotic for patients undergoing procedures without the need for tracheal intubation. This review focuses on the application of dexmedetomidine as a sedative and/or total anesthetic in patients undergoing procedures without the need for tracheal intubation. Dexmedetomidine was used for sedation in monitored anesthesia care (MAC, airway procedures including fiberoptic bronchoscopy, dental procedures, ophthalmological procedures, head and neck procedures, neurosurgery, and vascular surgery. Additionally, dexmedetomidine was used for the sedation of pediatric patients undergoing different type of procedures such as cardiac catheterization and magnetic resonance imaging. Dexmedetomidine loading dose ranged from 0.5 to 5 μg kg-1, and infusion dose ranged from 0.2 to 10 μg kg-1 h-1. Dexmedetomidine was administered in conjunction with local anesthesia and/or other sedatives. Ketamine was administered with dexmedetomidine and opposed its bradycardiac effects. Dexmedetomidine may by useful in patients needing sedation without tracheal intubation. The literature suggests potential use of dexmedetomidine solely or as an adjunctive agent to other sedation agents. Dexmedetomidine was especially useful when spontaneous breathing was essential such as in procedures on the airway, or when sudden awakening from sedation was required such as for cooperative clinical examination during craniotomies.Keywords: dexmedetomidine, sedation, nonintubated patients

Sedation in a radiology department--do radiologists follow their own guidelines?

Science.gov (United States)

Eason, D; Chakraverty, S; Wildsmith, J A W

2011-05-01

The Royal College of Radiologists (RCR) published guidelines in 2003 which aimed to standardise and improve the safety of sedation in the modern Radiology department. As sedation requirements increase, we decided to audit our own departments understandings and practice with respect to sedation. A repeat audit cycle was performed following a re-educational lecture, one year later. Three common sedation case scenarios were incorporated into a questionnaire which detailed questioning on requirements for fasting, monitoring and the order and use of sedation drugs alongside analgesics. These were compared to the 2003 RCR guidelines. The audit was recycled at one year. Despite the RCR guidelines, freely available on the RCR website, there was a persisting variation in practice which revealed a lack of awareness of the requirements for adequate fasting and the importance of giving the opiate before the benzodiazepine (sedative) agent in cases where a combination are chosen. The audit did show a trend towards using shorter acting benzodiazepines, which is in keeping with the guidelines. Monitoring of vital signs was generally, well carried out. General awareness of the RCR guidelines for safe sedation in the Radiology department was initially low and practice found to be variable. Re-education saw some improvements but also, some persisting habitual deviations from the guidelines, particularly with respect to the order in which the opiate and sedative benzodiazepine were given.

Understanding premixed flame chemistry of gasoline fuels by comparing quantities of interest

KAUST Repository

Selim, Hatem

2016-07-23

Gasoline fuels are complex mixtures that vary in composition depending on crude oil feedstocks and refining processes. Gasoline combustion in high-speed spark ignition engines is governed by flame propagation, so understanding fuel composition effects on premixed flame chemistry is important. In this study, the combustion chemistry of low-pressure, burner-stabilized, premixed flames of two gasoline fuels was investigated under stoichiometric conditions. Flame speciation was conducted using vacuum-ultraviolet synchrotron photoionization time-of-flight molecular beam mass spectroscopy. Stable end-products, intermediate hydrocarbons, and free radicals were detected and quantified. In addition, several isomeric species in the reaction pool were distinguished and quantified with the help of the highly tunable synchrotron radiation. A comparison between the products of both flames is presented and the major differences are highlighted. Premixed flame numerical simulations were conducted using surrogate fuel kinetic models for each flame. Furthermore, a new approach was developed to elucidate the main discrepancies between experimental measurements and the numerical predictions by comparing quantities of interest. © 2016.

Flamelet Surface Density and Burning Rate Integral in Premixed Combustion

National Research Council Canada - National Science Library

Gouldin, F

1999-01-01

We have developed, tested and applied in V-flames and a spark ignition engine a new experimental method, crossed-plane laser imaging, for measuring flamelet surface normals in premixed turbulent flames...

Chloral hydrate sedation in radiology: retrospective audit of reduced dose

International Nuclear Information System (INIS)

Bracken, Jennifer; Heaslip, Ingrid; Ryan, Stephanie

2012-01-01

Chloral hydrate (CH) is safe and effective for sedation of suitable children. The purpose of this study was to assess whether adequate sedation is achieved with reduced CH doses. We retrospectively recorded outpatient CH sedations over 1 year. We defined standard doses of CH as 50 mg/kg (infants) and 75 mg/kg (children >1 year). A reduced dose was defined as at least 20% lower than the standard dose. In total, 653 children received CH sedation (age, 1 month-3 years 10 months), 42% were given a reduced initial dose. Augmentation dose was required in 10.9% of all children, and in a higher proportion of children >1 year (15.7%) compared to infants (5.7%; P 1 year (95.3%; P = 0.03). A reduced initial dose had no negative effect on outcome (P = 0.19) or time to sedation. No significant complications were seen. We advocate sedation with reduced CH doses (40 mg/kg for infants; 60 mg/kg for children >1 year of age) for outpatient imaging procedures when the child is judged to be quiet or sleepy on arrival. (orig.)

Fospropofol Disodium for Sedation in Elderly Patients Undergoing Flexible Bronchoscopy.

Science.gov (United States)

Silvestri, Gerard A; Vincent, Brad D; Wahidi, Momen M

2011-01-01

BACKGROUND: Fospropofol disodium is a water-soluble prodrug of propofol. A subset analysis was undertaken of elderly patients (≥65 y) undergoing flexible bronchoscopy, who were part of a larger multicenter, randomized, double-blind study. METHODS: Patients received fentanyl citrate (50 mcg) followed by fospropofol at initial (4.88mg/kg) and supplemental (1.63mg/kg) doses. The primary end point was sedation success (3 consecutive Modified Observer's Assessment of Alertness/Sedation scores of ≤4 and procedure completion without alternative sedative or assisted ventilation). Treatment success, time to fully alert, patient and physician satisfaction, and safety/tolerability were also evaluated. RESULTS: In the elderly patients subset (n=61), sedation success was 92%, the mean time to fully alert was 8.0±10.9 min, and memory retention was 72% during recovery, and these were comparable with the younger patients subgroup (age, Sedation-related adverse events occurred in 23% of the elderly and 18% of the younger patients (age, sedation, rapid time to fully alert, and high satisfaction in this elderly subset undergoing flexible bronchoscopy, which was comparable with outcomes in younger patients.

Feasibility of measuring memory response to increasing dexmedetomidine sedation in children

OpenAIRE

Mason, K. P.; Kelhoffer, E. R.; Prescilla, R.; Mehta, M.; Root, J. C.; Young, V. J.; Robinson, F.; Veselis, R. A.

2017-01-01

Background. The memory effect of dexmedetomidine has not been prospectively evaluated in children. We evaluated the feasibility of measuring memory and sedation responses in children during dexmedetomidine sedation for non-painful radiological imaging studies. Secondarily, we quantified changes in memory in relation to the onset of sedation.

Sedatives for opiate withdrawal in newborn infants.

Science.gov (United States)

Osborn, David A; Jeffery, Heather E; Cole, Michael J

2010-10-06

Neonatal abstinence syndrome (NAS) due to opiate withdrawal may result in disruption of the mother-infant relationship, sleep-wake abnormalities, feeding difficulties, weight loss and seizures. Treatments used to ameliorate symptoms and reduce morbidity include opiates, sedatives and non-pharmacological treatments. To assess the effectiveness and safety of using a sedative compared to a non-opiate control for NAS due to withdrawal from opiates, and to determine which type of sedative is most effective and safe. This update included searches of the Cochrane Central Register of Controlled Trials (Issue 1, 2010), MEDLINE 1966 to April 2010 and abstracts of conference proceedings. Trials enrolling infants with NAS born to mothers with an opiate dependence with > 80% follow-up and using random or quasi-random allocation to sedative or control. Control could include another sedative or non-pharmacological treatment. Each author assessed study quality and extracted data independently. Seven studies enrolling 385 patients were included. There were substantial methodological concerns for most studies including the use of quasi-random allocation methods and sizeable, largely unexplained differences in reported numbers allocated to each group.One study reported phenobarbitone compared to supportive care alone did not reduce treatment failure or time to regain birthweight, but resulted in a significant reduction in duration of supportive care (MD -162.1 min/day, 95% CI -249.2, -75.1). Comparing phenobarbitone to diazepam, meta-analysis of two studies found phenobarbitone resulted in a significant reduction in treatment failure (typical RR 0.39, 95% CI 0.24, 0.62). Comparing phenobarbitone with chlorpromazine, one study reported no significant difference in treatment failure.In infants treated with an opiate, one study reported addition of clonidine resulted in no significant difference in treatment failure, seizures or mortality. In infants treated with an opiate, one study

LES of a laboratory-scale turbulent premixed bunsen flame using FSD, PCM-FPI and thickened flame models

NARCIS (Netherlands)

Hernandez Perez, F.E.; Yuen, F.T.C.; Groth, C.P.T.; Gülder, O.L.

2011-01-01

Large-eddy simulations (LES) of a turbulent premixed Bunsen flame were carried out with three subfilter-scale (SFS) modelling approaches for turbulent premixed combustion. One approach is based on the artificially thickened flame and power-law flame wrinkling models, the second approach is based on

Randomised clinical trial: a 'nudge' strategy to modify endoscopic sedation practice.

LENUS (Irish Health Repository)

Harewood, G C

2011-05-17

Background  In behavioural economics, a \\'nudge\\' describes configuration of a choice to encourage a certain action without taking away freedom of choice. Aim  To determine the impact of a \\'nudge\\' strategy - prefilling either 3 mL or 5 mL syringes with midazolam - on endoscopic sedation practice. Methods  Consecutive patients undergoing sedation for EGD or colonoscopy were enrolled. On alternate weeks, midazolam was prefilled in either 3 mL or 5 mL syringes. Preprocedure sedation was administered by the endoscopist to achieve moderate conscious sedation; dosages were at the discretion of the endoscopist. Meperidine was not prefilled. Results  Overall, 120 patients received sedation for EGD [59 (5 mL), 61 (3 mL)] and 86 patients were sedated for colonoscopy [38 (5 mL), 48 (3 mL)]. For EGDs, average midazolam dose was significantly higher in the 5-mL group (5.2 mg) vs. 3-mL group (3.3 mg), (P < 0.0001); for colonoscopies, average midazolam dose was also significantly higher in the 5-mL group (5.1 mg) vs. 3-mL group (3.3 mg), (P < 0.0001). There was no significant difference in mean meperidine dose (42.1 mg vs. 42.8 mg, P = 0.9) administered to both colonoscopy groups. No adverse sedation-related events occurred; no patient required reversal of sedation. Conclusions  These findings demonstrate that \\'nudge\\' strategies may hold promise in modifying endoscopic sedation practice. Further research is required to explore the utility of \\'nudges\\' in impacting other aspects of endoscopic practice.

Palliative Sedation: An Analysis of International Guidelines and Position Statements.

Science.gov (United States)

Gurschick, Lauren; Mayer, Deborah K; Hanson, Laura C

2015-09-01

To describe the suggested clinical practice of palliative sedation as it is presented in the literature and discuss available guidelines for its use. CINAHL, PubMed, and Web of Science were searched for publications since 1997 for recommended guidelines and position statements on palliative sedation as well as data on its provision. Keywords included palliative sedation, terminal sedation, guidelines, United States, and end of life. Inclusion criteria were palliative sedation policies, frameworks, guidelines, or discussion of its practice, general or oncology patient population, performance of the intervention in an inpatient unit, for humans, and in English. Exclusion criteria were palliative sedation in children, acute illness, procedural, or burns, and predominantly ethical discussions. Guidelines were published by American College of Physicians-American Society of Internal Medicine (2000), Hospice and Palliative Nurses Association (2003), American Academy of Hospice and Palliative Medicine (2006), American Medical Association (2008), Royal Dutch Medical Association (2009), European Association for Palliative Care (2009), National Hospice and Palliative Care Organization (2010), and National Comprehensive Cancer Network (2012). Variances throughout guidelines include definitions of the practice, indications for its use, continuation of life-prolonging therapies, medications used, and timing/prognosis. The development and implementation of institutional-based guidelines with clear stance on the discussed variances is necessary for consistency in practice. Data on provision of palliative sedation after implementation of guidelines needs to be collected and disseminated for a better understanding of the current practice in the United States. © The Author(s) 2014.

Sedation in palliative care – a critical analysis of 7 years experience

Science.gov (United States)

Muller-Busch, H Christof; Andres, Inge; Jehser, Thomas

2003-01-01

Background The administration of sedatives in terminally ill patients becomes an increasingly feasible medical option in end-of-life care. However, sedation for intractable distress has raised considerable medical and ethical concerns. In our study we provide a critical analysis of seven years experience with the application of sedation in the final phase of life in our palliative care unit. Methods Medical records of 548 patients, who died in the Palliative Care Unit of GK Havelhoehe between 1995–2002, were retrospectively analysed with regard to sedation in the last 48 hrs of life. The parameters of investigation included indication, choice and kind of sedation, prevalence of intolerable symptoms, patients' requests for sedation, state of consciousness and communication abilities during sedation. Critical evaluation included a comparison of the period between 1995–1999 and 2000–2002. Results 14.6% (n = 80) of the patients in palliative care had sedation given by the intravenous route in the last 48 hrs of their life according to internal guidelines. The annual frequency to apply sedation increased continuously from 7% in 1995 to 19% in 2002. Main indications shifted from refractory control of physical symptoms (dyspnoea, gastrointestinal, pain, bleeding and agitated delirium) to more psychological distress (panic-stricken fear, severe depression, refractory insomnia and other forms of affective decompensation). Patients' and relatives' requests for sedation in the final phase were significantly more frequent during the period 2000–2002. Conclusion Sedation in the terminal or final phase of life plays an increasing role in the management of intractable physical and psychological distress. Ethical concerns are raised by patients' requests and needs on the one hand, and the physicians' self-understanding on the other hand. Hence, ethically acceptable criteria and guidelines for the decision making are needed with special regard to the nature of refractory

Sedation in palliative care – a critical analysis of 7 years experience

Directory of Open Access Journals (Sweden)

Andres Inge

2003-05-01

Full Text Available Abstract Background The administration of sedatives in terminally ill patients becomes an increasingly feasible medical option in end-of-life care. However, sedation for intractable distress has raised considerable medical and ethical concerns. In our study we provide a critical analysis of seven years experience with the application of sedation in the final phase of life in our palliative care unit. Methods Medical records of 548 patients, who died in the Palliative Care Unit of GK Havelhoehe between 1995–2002, were retrospectively analysed with regard to sedation in the last 48 hrs of life. The parameters of investigation included indication, choice and kind of sedation, prevalence of intolerable symptoms, patients' requests for sedation, state of consciousness and communication abilities during sedation. Critical evaluation included a comparison of the period between 1995–1999 and 2000–2002. Results 14.6% (n = 80 of the patients in palliative care had sedation given by the intravenous route in the last 48 hrs of their life according to internal guidelines. The annual frequency to apply sedation increased continuously from 7% in 1995 to 19% in 2002. Main indications shifted from refractory control of physical symptoms (dyspnoea, gastrointestinal, pain, bleeding and agitated delirium to more psychological distress (panic-stricken fear, severe depression, refractory insomnia and other forms of affective decompensation. Patients' and relatives' requests for sedation in the final phase were significantly more frequent during the period 2000–2002. Conclusion Sedation in the terminal or final phase of life plays an increasing role in the management of intractable physical and psychological distress. Ethical concerns are raised by patients' requests and needs on the one hand, and the physicians' self-understanding on the other hand. Hence, ethically acceptable criteria and guidelines for the decision making are needed with special regard to

Experimental study on flame propagation characteristics of Hydrogen premixed gas in gas pipeline

Science.gov (United States)

Ma, Danzhu; Li, Zhuang; Jia, Fengrui; Li, Zhou

2018-06-01

Hydrogen is the cleanest high-energy gas fuel, and also is the main industrial material. However, hydrogen is more explosive and more powerful than conventional gas fuels, which restricts its application. In particular, the expansion of premixed combustion under a strong constraint is more complicated, the reaction spreads faster. The flame propagation characteristics of premixed hydrogen/air were investigated by experiment. The mechanism of reaction acceleration is discussed, and then the speed of the flame propagation and the reaction pressure were tested and analysed.

Sedative properties of Mitracarpus villosus leaves in mice

African Journals Online (AJOL)

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anxiolytics increase the head-dip counts. The reduction in the number of head dips shown by the extract is therefore an indication of the presence of psychoactive constituents that are sedative in nature. The sedative property of the plant was confirmed by its ability to potentiate the duration of diazepam induced sleep.

Recording EEG In Young Children Without Sedation | Curuneaux ...

African Journals Online (AJOL)

Background Although it has been considered that sedation in children undergoing EEG tests is effective and safe and complications are infrequent, occasionally adverse sedation-related events are presented. Objective The aim of this work was to determine if it is possible to carry out EEG in children up to 4 years old ...

Liftoff characteristics of partially premixed flames under normal and microgravity conditions

Energy Technology Data Exchange (ETDEWEB)

Lock, Andrew J.; Briones, Alejandro M.; Aggarwal, Suresh K. [Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL 60607 (United States); Qin, Xiao [Department of Mechanical & amp; Aerospace Engineering, Princeton University, Princeton, NJ 08544 (United States); Puri, Ishwar K. [Department of Engineering Science and Mechanics, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Hegde, Uday [National Center for Microgravity Research, Cleveland, OH 44135 (United States)

2005-11-01

An experimental and computational investigation on the liftoff characteristics of laminar partially premixed flames (PPFs) under normal (1-g) and microgravity ({mu}-g) conditions is presented. Lifted methane-air PPFs were established in axisymmetric coflowing jets using nitrogen dilution and various levels of partial premixing. The {mu}-g experiments were conducted in the 2.2-s drop tower at the NASA Glenn Research Center. A time-accurate, implicit algorithm that uses a detailed description of the chemistry and includes radiation effects is used for the simulations. The predictions are validated through a comparison of the flame reaction zone topologies, liftoff heights, lengths, and oscillation frequencies. The effects of equivalence ratio, gravity, jet velocity, and radiation on flame topology, liftoff height, flame length, base structure, and oscillation frequency are characterized. Both the simulations and measurements indicate that under identical conditions, a lifted {mu}-g PPF is stabilized closer to the burner compared with the 1-g flame, and that the liftoff heights of both 1-g and {mu}-g flames decrease with increasing equivalence ratio and approach their respective nonpremixed flame limits. The liftoff height also increases as the jet velocity is increased. In addition, the flame base structure transitions from a triple- to a double-flame structure as the flame liftoff height decreases. A modified flame index is developed to distinguish between the rich premixed, lean premixed, and nonpremixed reaction zones near the flame base. The 1-g lifted flames exhibit well-organized oscillations due to buoyancy-induced instability, while the corresponding {mu}-g flames exhibit steady-state behavior. The effect of thermal radiation is to slightly decrease the liftoff heights of both 1-g and {mu}-g flames under coflow conditions.

Palliative sedation for terminally ill cancer patients in a tertiary cancer center in Shanghai, China.

Science.gov (United States)

Gu, Xiaoli; Cheng, Wenwu; Chen, Menglei; Liu, Minghui; Zhang, Zhe

2015-01-01

There are a number of studies dedicated to characteristics of sedation, but these studies are mostly bound to western country practices. The aim of this study is to describe the characteristics of patients who suffered from cancer and who had been sedated until their death in Shanghai, China. Retrospective medical data of 244 terminally ill cancer patients including 82 sedated patients were collected. Data collected included demographic characteristics, disease-related characteristics and details of the sedation. In sedated cases, patients and/or caregivers gave the consent to start palliative sedation due to unmanageable symptoms. On average, sedation was performed 24.65(±1.78)hours before death. Agitated delirium and dyspnea were the most frequent indications for palliative sedation. There was no significant difference in survival time from admission till death between sedated and non-sedated patients (p > 0.05). Palliative sedation is effective for reducing terminally ill cancer patients' suffering without hastening death. Prospective research is needed to determine the optimal conditions for Chinese patients including indications, decision making process, informed consent, cultural and ethical issues, type of sedation and drugs.

Fuel and combustion stratification study of Partially Premixed Combustion

NARCIS (Netherlands)

Izadi Najafabadi, M.; Dam, N.; Somers, B.; Johansson, B.

2016-01-01

Relatively high levels of stratification is one of the main advantages of Partially Premixed Combustion (PPC) over the Homogeneous Charge Compression Ignition (HCCI) concept. Fuel stratification smoothens heat release and improves controllability of this kind of combustion. However, the lack of a

Dissociations in the expression of the sedative effects of triazolam.

Science.gov (United States)

Weingartner, H J; Sirocco, K; Rawlings, R; Joyce, E; Hommer, D

1995-05-01

Fifteen normal volunteers were administered 0.250, 0.375, and 0.500 mg of triazolam and placebo in a double-blind repeated measures cross-over design. Subjects demonstrated dose-dependent impairments in free recall, a test of explicit memory requiring awareness and reflection, and sedation as assessed by objective behavioral measures (the digit symbol substitution task) and subjective visual analogue scales. The sedative drug response did not account for the impairment in free recall. Differences in performance of the two tests of sedation indicated that the effect of this drug on reflective processes accounts for impairment in episodic memory and the inability to track the sedative effects of this drug at the higher doses tested in this study.

The Effect of Acepromazine Alone or in Combination with Methadone, Morphine, or Tramadol on Sedation and Selected Cardiopulmonary Variables in Sheep

Directory of Open Access Journals (Sweden)

Lilian Toshiko Nishimura

2017-01-01

Full Text Available The sedative and selected cardiopulmonary effects of acepromazine alone or in combination with methadone, morphine, or tramadol were compared in sheep. Six ewes were randomly assigned to treatments: A (0.05 mg/kg acepromazine, AM (A plus 0.5 mg/kg methadone, AMO (A plus 0.5 mg/kg morphine, and AT (A plus 5 mg/kg tramadol. Parameters were assessed before sedative drug administration (baseline and every 15 minutes thereafter, for two hours. Treatments A and AM were associated with increases in sedation score for 60 minutes and treatments AMO and AT for 30 minutes; however, there were no significant differences between treatments. There was a decrease in mean arterial pressure compared to baseline values in treatment A at 15, 45, 60, and 90 minutes, in treatment AM at 15 minutes, and in treatment AT from 45 to 120 minutes. Arterial blood carbon dioxide pressure increased at all time points in all treatments. Arterial oxygen pressure decreased in treatment AMO at 15, 30, and 120 minutes and in treatment AT at 15–45, 105, and 120 minutes, compared to baseline. Acepromazine alone causes a level of sedation similar to that observed when it is coadministered with opioids methadone, morphine, and tramadol. These combinations did not cause clinical cardiopulmonary changes.

Laser-saturated fluorescence of nitric oxide and chemiluminescence measurements in premixed ethanol flames

Energy Technology Data Exchange (ETDEWEB)

Marques, Carla S.T.; Barreta, Luiz G.; Sbampato, Maria E.; dos Santos, Alberto M. [Aerothermodynamic and Hypersonic Division, Institute of Advanced Studies - General Command of Aerospatial Technology, Rodovia dos Tamoios, km 5.5, 12228-001 Sao Jose dos Campos - SP (Brazil)

2010-11-15

In this study, nitric oxide laser-saturated fluorescence (LSF) measurements were acquired from premixed ethanol flames at atmospheric pressure in a burner. NO-LSF experimental profiles for fuel-rich premixed ethanol flames ({phi} = 1.34 and {phi} = 1.66) were determined through the excitation/detection scheme of the Q{sub 2}(26.5) rotational line in the A{sup 2}{sigma}{sup +} - X{sup 2}{pi} (0,0) vibronic band and {gamma}(0,1) emission band. A calibration procedure by NO doping into the flame was applied to establish the NO concentration profiles in these flames. Chemiluminescent emission measurements in the (0, 0) vibronic emission bands of the OH{sup *} (A{sup 2}{sigma}{sup +} - X{sup 2}{pi}) and CH{sup *}(A{sup 2}{delta} - X{sup 2}{pi}) radicals were also obtained with high spatial and spectral resolution for fuel-rich premixed ethanol flames to correlate them with NO concentrations. Experimental chemiluminescence profiles and the ratios of the integrated areas under emission spectra (A{sub CH*}/A{sub CH*}(max.) and A{sub CH*}/A{sub OH*}) were determined. The relationships between chemiluminescence and NO concentrations were established along the premixed ethanol flames. There was a strong connection between CH{sup *} radical chemiluminescence and NO formation and the prompt-NO was identified as the governing mechanism for NO production. The results suggest the optimum ratio of the chemiluminescence of two radicals (A{sub CH*}/A{sub OH*}) for NO diagnostic purposes. (author)

Effects of premixed flames on turbulence and turbulent scalar transport

Energy Technology Data Exchange (ETDEWEB)

Lipatnikov, A.N.; Chomiak, J. [Department of Applied Mechanics, Chalmers University of Technology, 412 75 Goeteborg (Sweden)

2010-02-15

Experimental data and results of direct numerical simulations are reviewed in order to show that premixed combustion can change the basic characteristics of a fluctuating velocity field (the so-called flame-generated turbulence) and the direction of scalar fluxes (the so-called countergradient or pressure-driven transport) in a turbulent flow. Various approaches to modeling these phenomena are discussed and the lack of a well-elaborated and widely validated predictive approach is emphasized. Relevant basic issues (the transition from gradient to countergradient scalar transport, the role played by flame-generated turbulence in the combustion rate, the characterization of turbulence in premixed flames, etc.) are critically considered and certain widely accepted concepts are disputed. Despite the substantial progress made in understanding the discussed effects over the past decades, these basic issues strongly need further research. (author)

Feeding response of sport fish after electrical immobilization, chemical sedation, or both

Science.gov (United States)

Meinertz, Jeffery R.; Fredricks, Kim T.; Ambrose, Ryan D.; Jackan, Leanna M.; Wise, Jeremy K.

2012-01-01

Fishery managers frequently capture wild fish for a variety of fishery management activities. Though some activities can be accomplished without immobilizing the fish, others are accomplished more readily, humanely, and safely (for both the handler and the fish) when fish are immobilized by physical (e.g., electrical immobilization) or chemical sedation. A concern regarding the use of chemical sedatives is that chemical residues may remain in the fillet tissue after the fish recovers from sedation. If those residues are harmful to humans, there is some risk that a postsedated fish released to public waters may be caught and consumed by an angler. To characterize this risk, a series of four trials were conducted. Three trials assessed feeding activity after hatchery-reared fish were electrically immobilized, chemically sedated, or both, and one trial assessed the likelihood of an angler catching a wild fish that had been electrically immobilized and chemically sedated. Results from the first trial indicated that the feeding activity of laboratory habituated fish was variable among and within species after electrical immobilization, chemical sedation, or both. Results from the second trial indicated that the resumption of feeding activity was rapid after being mildly sedated for 45 min. Results from the third trial indicated that the feeding activity of outdoor, hatchery-reared fish was relatively aggressive after fish had been chemically sedated. Results from the fourth trial indicated that the probability of capturing wild fish in a more natural environment by angling after fish had been electrically immobilized and chemically sedated is not likely, i.e., in a group of five fish caught, 3 out of 100 times one would be a fish that had been sedated.

Muslim physicians and palliative care: attitudes towards the use of palliative sedation.

Science.gov (United States)

Muishout, George; van Laarhoven, Hanneke W M; Wiegers, Gerard; Popp-Baier, Ulrike

2018-05-08

Muslim norms concerning palliative sedation can differ from secular and non-Muslim perceptions. Muslim physicians working in a Western environment are expected to administer palliative sedation when medically indicated. Therefore, they can experience tension between religious and medical norms. To gain insight into the professional experiences of Muslim physicians with palliative sedation in terms of religious and professional norms. Interpretative phenomenological study using semi-structured interviews to take a closer look at the experiences of Muslim physicians with palliative sedation. Data were recorded, transcribed and analysed by means of interpretative phenomenological analysis (IPA). Ten Muslim physicians, working in the Netherlands, with professional experience of palliative sedation. Two main themes were identified: professional self-concept and attitudes towards death and dying. Participants emphasized their professional responsibility when making treatment decisions, even when these contravened the prevalent views of Islamic scholars. Almost all of them expressed the moral obligation to fight their patients' pain in the final stage of life. Absence of acceleration of death was considered a prerequisite for using palliative sedation by most participants. Although the application of palliative sedation caused friction with their personal religious conceptions on a good death, participants followed a comfort-oriented care approach corresponding to professional medical standards. All of them adopted efficient strategies for handling of palliative sedation morally and professionally. The results of this research can contribute to and provide a basis for the emergence of new, applied Islamic ethics regarding palliative sedation.

Continuous palliative sedation until death: practice after introduction of the Dutch national guideline.

Science.gov (United States)

Swart, Siebe J; van der Heide, Agnes; Brinkkemper, Tijn; van Zuylen, Lia; Perez, Roberto; Rietjens, Judith

2012-09-01

In 2005, a national palliative guideline was launched in The Netherlands. The authors describe the practice of continuous palliative sedation until death (CPS) after the introduction of this guideline. In 2008, a random sample of physicians (n=1580) were asked to fill out a questionnaire regarding the last patient in whom they had provided CPS until death. The response was 38%. In all, 82% of the respondents were aware of the existence of the national guideline. Dyspnoea, pain and physical exhaustion were most often mentioned as decisive indications for continuous sedation. The decision to use sedation was discussed with all competent patients, but in 18% this merely involved informing the patient. Life expectancy at the start of continuous sedation was estimated to be less than 2 weeks in 97% of the cases. In 14%, the physicians had felt pressure to start the sedation, predominantly from patients and relatives. Physicians were present at the start of the sedation in 81% of the cases. Midazolam was used to induce the sedation in 92%. Overall, 41% of the physicians estimated that continuous sedation had hastened death to some extent. Most physicians thought that patients' complaints were adequately relieved by continuous sedation, that relatives were satisfied and that a good quality of dying was achieved. Continuous palliative sedation practice in The Netherlands largely reflects the recommendations from the national guideline. Issues needing further attention are the pressure felt by physicians to start continuous sedation and the potential life-shortening effect as mentioned by the physicians.

Modeling of Dissipation Element Statistics in Turbulent Non-Premixed Jet Flames

Science.gov (United States)

Denker, Dominik; Attili, Antonio; Boschung, Jonas; Hennig, Fabian; Pitsch, Heinz

2017-11-01

The dissipation element (DE) analysis is a method for analyzing and compartmentalizing turbulent scalar fields. DEs can be described by two parameters, namely the Euclidean distance l between their extremal points and the scalar difference in the respective points Δϕ . The joint probability density function (jPDF) of these two parameters P(Δϕ , l) is expected to suffice for a statistical reconstruction of the scalar field. In addition, reacting scalars show a strong correlation with these DE parameters in both premixed and non-premixed flames. Normalized DE statistics show a remarkable invariance towards changes in Reynolds numbers. This feature of DE statistics was exploited in a Boltzmann-type evolution equation based model for the probability density function (PDF) of the distance between the extremal points P(l) in isotropic turbulence. Later, this model was extended for the jPDF P(Δϕ , l) and then adapted for the use in free shear flows. The effect of heat release on the scalar scales and DE statistics is investigated and an extended model for non-premixed jet flames is introduced, which accounts for the presence of chemical reactions. This new model is validated against a series of DNS of temporally evolving jet flames. European Research Council Project ``Milestone''.

Non-sedation versus sedation with a daily wake-up trial in critically ill patients recieving mechanical ventilation - effects on long-term cognitive function

DEFF Research Database (Denmark)

Nedergaard, Helene Korvenius; Jensen, Hanne Irene; Stylsvig, Mette

2016-01-01

trauma, status epilepticus, patients treated with therapeutic hypothermia and patients with severe hypoxia). The experimental intervention will be non-sedation supplemented with pain management during mechanical ventilation. The control intervention will be sedation with a daily wake-up attempt...

A randomized controlled trial of daily sedation interruption in critically ill children

NARCIS (Netherlands)

Vet, N.J.; Wildt, S.N. de; Verlaat, C.W.; Knibbe, C.A.; Mooij, M.G.; Woensel, J.B. van; Rosmalen, J. van; Tibboel, D.; Hoog, M. de

2016-01-01

PURPOSE: To compare daily sedation interruption plus protocolized sedation (DSI + PS) to protocolized sedation only (PS) in critically ill children. METHODS: In this multicenter randomized controlled trial in three pediatric intensive care units in the Netherlands, mechanically ventilated critically

A randomized controlled trial of daily sedation interruption in critically ill children

NARCIS (Netherlands)

N.J. Vet (Nienke); S.N. de Wildt (Saskia); C.W.M. Verlaat (Carin); C.A.J. Knibbe (Catherijne); M.G. Mooij (Miriam); J.B. van Woensel (Job); J.M. van Rosmalen (Joost); D. Tibboel (Dick); M. de Hoog (Matthijs)

2016-01-01

textabstractPurpose: To compare daily sedation interruption plus protocolized sedation (DSI + PS) to protocolized sedation only (PS) in critically ill children. Methods: In this multicenter randomized controlled trial in three pediatric intensive care units in the Netherlands, mechanically

The Effect of Premixed Al-Cu Powder on the Stir Zone in Friction Stir Welding of AA3003-H18

Science.gov (United States)

Abnar, B.; Kazeminezhad, M.; Kokabi, A. H.

2015-02-01

In this research, 3-mm-thick AA3003-H18 non-heat-treatable aluminum alloy plates were joined by friction stir welding (FSW). It was performed by adding pure Cu and premixed Cu-Al powders at various rotational speeds of 800, 1000, and 1200 rpm and constant traveling speeds of 100 mm/min. At first, the powder was filled into the gap (0.2 or 0.4 mm) between two aluminum alloy plates, and then the FSW process was performed in two passes. The microstructure, mechanical properties, and formation of intermetallic compounds were investigated in both cases of using pure Cu and premixed Al-Cu powders. The results of using pure Cu and premixed Al-Cu powders were compared in the stir zone at various rotational speeds. The copper particle distribution and formation of Al-Cu intermetallic compounds (Al2Cu and AlCu) in the stir zone were desirable using premixed Al-Cu powder into the gap. The hardness values were significantly increased by formation of Al-Cu intermetallic compounds in the stir zone and it was uniform throughout the stir zone when premixed Al-Cu powder was used. Also, longitudinal tensile strength from the stir zone was higher when premixed Al-Cu powder was used instead of pure Cu powder.

Palliative sedation and moral distress: A qualitative study of nurses.

Science.gov (United States)

Lokker, M E; Swart, S J; Rietjens, J A C; van Zuylen, L; Perez, R S G M; van der Heide, A

2018-04-01

Clinical nursing practice may involve moral distress, which has been reported to occur frequently when nurses care for dying patients. Palliative sedation is a practice that is used to alleviate unbearable and refractory suffering in the last phase of life and has been linked to distress in nurses. The aim of this study was to explore nurses' reports on the practice of palliative sedation focusing on their experiences with pressure, dilemmas and morally distressing situations. In-depth interviews with 36 nurses working in hospital, nursing home or primary care. Several nurses described situations in which they felt that administration of palliative sedation was in the patient's best interest, but where they were constrained from taking action. Nurses also reported on situations where they experienced pressure to be actively involved in the provision of palliative sedation, while they felt this was not in the patient's best interest. The latter situation related to (1) starting palliative sedation when the nurse felt not all options to relieve suffering had been explored yet; (2) family requesting an increase of the sedation level where the nurse felt that this may involve unjustified hastening of death; (3) a decision by the physician to start palliative sedation where the patient had previously expressed an explicit wish for euthanasia. Nurses experienced moral distress in situations where they were not able to act in what they believed is the patient's best interest. Situations involving moral distress require nurses to be well informed and able to adequately communicate with suffering patients, distressed family and physicians. Copyright © 2018 Elsevier Inc. All rights reserved.

A randomized controlled trial of daily sedation interruption in critically ill children

NARCIS (Netherlands)

Vet, Nienke J.; de Wildt, Saskia N.; Verlaat, Carin W. M.; Knibbe, Catherijne A. J.; Mooij, Miriam G.; van Woensel, Job B. M.; van Rosmalen, Joost; Tibboel, Dick; de Hoog, Matthijs

2016-01-01

To compare daily sedation interruption plus protocolized sedation (DSI + PS) to protocolized sedation only (PS) in critically ill children. In this multicenter randomized controlled trial in three pediatric intensive care units in the Netherlands, mechanically ventilated critically ill children with

Properties of Ni-Mo steel prepared from premixed and prealloyed powder in sintered, forged and annealed state

International Nuclear Information System (INIS)

Salak, A.; Hrubjak, M.

Investigated were 2Ni-0.5Mo steel specimens made of premixed powder on the base of Hametag iron and of ATST-A prealloyed powder with graphite additives of 0.3% and 0.8%. In the sintered and forged state, specimens prepared from premixed powder exhibit better strength properties compared with those made of prealloyed ATST-A powder. After annealing, the carbon content has a different bearing on both systems. With premixed powder steel of 0.6% carbon content the tensile strength amounts to 1,800 MPa whilst that of prealloyed steel specimens with 0.2% carbon content is about 1,240 MPa. (author)

Effect of oxygen atoms dissociated by non-equilibrium plasma on flame of methane oxygen and argon pre-mixture gas

Science.gov (United States)

Akashi, Haruaki; Yoshinaga, Tomokazu; Sasaki, Koichi

2014-10-01

For more efficient way of combustion, plasma-assisted combustion has been investigated by many researchers. But it is very difficult to clarify the effect of plasma even on the flame of methane. Because there are many complex chemical reactions in combustion system. Sasaki et al. has reported that the flame length of methane and air premixed burner shortened by irradiating microwave power. They also measured emission from Second Positive Band System of nitrogen during the irradiation. The emission indicates existence of high energy electrons which are accelerated by the microwave. The high energy electrons also dissociate oxygen molecules easily and oxygen atom would have some effects on the flame. But the dissociation ratio of oxygen molecules by the non-equilibrium plasma is significantly low, compared to that in the combustion reaction. To clarify the effect of dissociated oxygen atoms on the flame, dependence of dissociation ratio of oxygen on the flame has been examined using CHEMKIN. It is found that in the case of low dissociation ratio of 10-6, the ignition of the flame becomes slightly earlier. It is also found that in the case of high dissociation ratio of 10-3, the ignition time becomes significantly earlier by almost half. This work was supported by KAKENHI (22340170).

[Survey of pediatric sedation in Japan--results of questionnaire to universities of dentistry].

Science.gov (United States)

Takeuchi, Lisa; Kuratani, Norifumi; Hoshijima, Hiroshi; Kikuchi, Hirosato

2010-12-01

Despite widespread use of sedation for stress management during dental treatment in adults, its prevalence of use for pediatric in patients Japan has not been clarified. We investigated here, the present situation of pediatric sedation by the questionnaire sent to the dental anesthesia departments of university hospitals in Japan. Postal survey was conducted of the dental anesthesia departments of university hospitals (29 institutions) throughout the country. Information was requested on hospital policy of indication and technique of pediatric sedation for dental treatment. The causes for avoiding pediatric sedation were also investigated. The response rate was 86.2% (25/29 institutions). Of these respondents, 16 institutions (64%, 16/25 institutions) employ sedation for pediatric dental treatment stress management. The cases performed were around 1-5 cases every month. However, the criteria for employment of pediatric sedation during dental treatment varied among institutes. They preferred to provide general endotracheal anesthesia for pediatric dental procedures, and tended to avoid sedation without airway security for children. The present survey suggests that pediatric sedation for stress management during dental treatment are employed in more than half of the dental university hospitals. However, there was little consensus regarding pediatric sedation during dental treatment among dental anesthesiologists in Japan.

Modeling of pollutant formation in fully premixing surface burners using a verified practice-oriented experimental reaction-kinetic calculation method. Final report

International Nuclear Information System (INIS)

Ruy, C.; Kremer, H.

1996-01-01

The intent of the present study was to simulate quantitatively pollutant formation in premixing surface burners and to describe qualitatively the share of the premixing flame in pollut emissions from atmospheric burners. For this purpose reaction-kinetic programmes for one-dimensional premixing flames were extended by a terms describing heat discharge through gas radiation. Furthermore, the calculation range for the flame was extended far into the secondary reaction zone. Temperature, CO, and NO x profiles were measured in the secondary reaction zone of premixing burners at standard pressure. The air-fuel ratio was calculated within the practically relevant range between 0.5 and 1.5, as was load behaviour. (DG) [de

Oxidative and biochemical responses in Brycon amazonicus anesthetized and sedated with Myrcia sylvatica (G. Mey.) DC. and Curcuma longa L. essential oils.

Science.gov (United States)

Saccol, Etiane M H; Londero, Érika P; Bressan, Caroline A; Salbego, Joseânia; Gressler, Luciane T; Silva, Lenise V F; Mourão, Rosa H V; Oliveira, Ricardo B; Llesuy, Susana F; Baldisserotto, Bernardo; Pavanato, Maria A

2017-05-01

To investigate the effects of rapid anesthesia and long-term sedation with the essential oils (EOs) of Myrcia sylvatica (EOMS) and Curcuma longa (EOCL) on biochemical and oxidative parameters in matrinxã. Prospective, randomized, laboratory experiment. A total of 72 matrinxã (Brycon amazonicus) adults weighing 404.8 ± 27.9 g were divided into eight groups of nine fish. Biochemical and oxidative effects were investigated in plasma and tissues of matrinxã subjected to rapid anesthesia (5 minutes) or long-term sedation (360 minutes, simulating the practice of transport) with EOMS (200 μL L -1 and 10 μL L -1 , respectively) and EOCL (500 μL L -1 and 40 μL L -1 , respectively). Transport simulation without sedation or anesthesia increased lipid peroxidation levels in the gills and kidney of fish in the control group. Anesthesia and sedation with EOs decreased cortisol concentrations and increased lactate concentrations compared with controls. Lipid peroxidation was lower in the brain, gills, liver and kidney of sedated and anesthetized fish, than in the control group. Anesthesia with EOs increased the activity of superoxide dismutase and glutathione-S-transferase in the brain, and catalase in the liver and gills, compared with controls. Long-term sedation with EOs increased superoxide dismutase, glutathione peroxidase and glutathione reductase activities in the brain, catalase in the liver, glutathione peroxidase and glutathione reductase in the gills and superoxide dismutase in the kidney. In general, nonprotein thiols content and total reactive antioxidant potential of tissues were higher after anesthesia and sedation with EOs compared with the control group. The concentrations of EOMS and EOCL used were effective at preventing a stress response and excess of reactive oxygen species formation. For these reasons, these substances may be recommended for use in the transportation of fish to improve survival and animal welfare. Copyright © 2017

A Favorable Course of Palliative Sedation: Searching for Indicators Using Caregivers' Perspectives

NARCIS (Netherlands)

Brinkkemper, T.; Rietjens, J.A.C.; Deliens, L.; Ribbe, M.W.; Swart, S.J.; Loer, S.A.; Zuurmond, W.W.A.; Perez, R.S.G.M.

2015-01-01

Objective:Comparing characteristics of a favorable sedation course during palliative sedation to a less favorable course based on the reports Dutch physicians and nurses.Results:Cases identified as having a favorable sedation course less often concerned a male patient (P = .019 nurses' cases),

Palliative sedation at home in the Netherlands: a nationwide survey among nurses

NARCIS (Netherlands)

Brinkkemper, T.; Klinkenberg, M.; Deliens, L.; Eliel, M.; Rietjens, J.A.C.; Zuurmond, W.W.A.; Perez, R.S.G.M.

2011-01-01

Aim. This paper is a report of a nationwide study conducted to assess experiences of nurses involved in palliative sedation at home after introduction of a physicians' guideline for palliative sedation. Background. Most studies investigating the practice of palliative sedation focus on physicians'

[Application of bispectral index monitoring in sedation and analgesia for flexible bronchoscopy].

Science.gov (United States)

Fang, S R; Liu, Y J; Su, N J; Shu, Y; Gu, W

2017-12-12

Objective: To investigate the feasibility of using bispectral index monitoring in sedation and analgesia for bronchoscopy. Methods: Totally 285 patients admitted to the Respiratory Medicine Department of Nanjing First Hospital for bronchoscopy between June 2016 and December 2016 were assigned, according to their own wishes, into a conscious sedation group (171 cases receiving local anesthesia and conscious sedation, 89 males, 82 females, mean age 59±10 years) and a control group (114 cases undergoing local anesthesia, 59 males, 55 females, average age 61±12 years). The 2 groups were compared in terms of operation time, blood pressure, heart rate and other indicators during bronchoscopy including incidence of adverse events, memory of the procedure, willingness to be re-examined, safety of sedation and analgesia for bronchoscopy under bispectral index monitoring, and patient satisfaction in the postoperative follow-up. Results: The conscious sedation group and the control group had no difference in age and sex ratio( P >0.05). Compared with the patients in the control group(operation time 16±5 min and systolic blood pressure 153±21 mmHg, 1 mmHg=0.133 kPa), those in the conscious sedation group had a shorter operation time(14±5 min) and a lower systolic blood pressure(144±22 mmHg), with statistically significant difference ( P sedation group and 92±12 mmHg and 87±14 times/min in the control group, P >0.05). Adverse events, overall intraoperative cough and bleeding were found to be significantly reduced in the conscious sedation group (27%, 4% and 13% and 60%, 13% and 35% in the control group, P sedation group, and 14% in the control group, P =0.72). Patient satisfaction and willingness to be re-examined were markedly higher in the conscious sedation group (97%) than in the controls (4%, P sedation and analgesia for bronchoscopy and has higher patient satisfaction, suggesting that it is a potential tool for use in clinical practice.

Assessment of patients' awareness and factors influencing patients' demands for sedation in endodontics.

Science.gov (United States)

Huh, Yoo Kyeom; Montagnese, Thomas A; Harding, Jarrod; Aminoshariae, Anita; Mickel, Andre

2015-02-01

Endodontic therapy is perceived by many as a procedure to be feared. Many studies have reported that fear and anxiety are major deterrents to seeking dental care in general, but only a few deal with the use of sedation in endodontic therapies. The purpose of this study was to assess patients' awareness of and factors influencing the potential demand for sedation in endodontics. We hypothesized that there is an association between demographic factors and the demand for sedation in endodontics. A survey consisting of 24 questions was given to patients 18 years and older who presented to the graduate endodontic clinic. Results were collected and statistically analyzed. Thirty-six percent of patients reported that their perception of sedation was being put to sleep, and 27% perceived it as related to or reducing pain. Concerns associated with endodontic therapy were the fear of pain (35%), fear of needles (16%), difficulty getting numb (10%), and anxiety (7%). The 2 major demographic factors that influenced the demand for sedation were cost and the level of anxiety (P endodontic therapy if the option of sedation was available. The demand for sedation in endodontics is high. Patients' understanding of sedation varies. More patients would consider having endodontic procedures if sedation was available. The provision of sedation by endodontists could result in more patients accepting endodontic therapies. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

A Survey of Hospice and Palliative Care Physicians Regarding Palliative Sedation Practices.

Science.gov (United States)

Lux, Michael R; Protus, Bridget McCrate; Kimbrel, Jason; Grauer, Phyllis

2017-04-01

Patients nearing the end of life may experience symptoms that are refractory to standard therapeutic options. Physicians may consider palliative sedation to relieve intolerable suffering. There is limited clinical literature regarding preferred medications for palliative sedation. To determine the preferred medications physicians use when implementing palliative sedation. An Internet-based, cross-sectional survey of hospice and palliative care physicians in the United States. A link to the survey was e-mailed to 3130 physician members of the American Academy of Hospice and Palliative Medicine, of which 381 physicians completed the survey. Physicians were not required to answer all questions. Nearly all (n = 335, 99%) respondents indicated that palliative sedation may be used (acceptable by 73% [n = 248] for refractory symptoms and acceptable by 26% [n = 87] only for imminently dying patients). Seventy-nine percent (n = 252) believed that opioids should not be used to induce palliative sedation but should be continued to provide pain control. Midazolam was the most commonly selected first-line choice for palliative sedation (n = 155, 42%). The most commonly reported second-line agents for the induction of palliative sedation were lorazepam, midazolam (for those who did not select midazolam as first-line agent), and phenobarbital with a reported preference of 20% (n = 49), 19% (n = 46), and 17% (n = 40), respectively. Of the physicians surveyed, 99% (n = 335) felt that palliative sedation is a reasonable treatment modality. Midazolam was considered a drug of choice for inducing and maintaining sedation, and opioids were continued for pain control.

Stressful experiences in relation to depth of sedation in mechanically ventilated patients.

Science.gov (United States)

Samuelson, Karin A M; Lundberg, Dag; Fridlund, Bengt

2007-01-01

In mechanically ventilated patients, sedatives and analgesics are commonly used to ensure comfort, but there is no documented knowledge about the impact of depth of sedation on patients' perception of discomfort. The aim of this study was, therefore, to investigate the relationship between stressful experiences and intensive care sedation, including the depth of sedation. During 18 months, 313 intubated mechanically ventilated adults admitted to two general intensive care units (ICU) for more than 24 h were included. Patients (n = 250) were interviewed on the general ward 5 days after ICU discharge using the ICU Stressful Experiences Questionnaire. Patient data including sedation scores as measured by the Motor Activity Assessment Scale (MAAS) were collected from hospital records after the interview. Of the 206 patients with memories of the intensive care, 82% remembered at least one experience as quite a bit or extremely bothersome. Multivariate analyses showed that higher proportion of MAAS score 3 (indicating more periods of wakefulness), longer ICU stay and being admitted emergent were factors associated with remembering stressful experiences of the ICU as more bothersome. The findings indicate that the depth of sedation has an impact on patients' perception of stressful experiences and that light sedation compared with heavy seems to increase the risk of perceiving experiences in the ICU as more bothersome. In reducing discomfort, depth of sedation and patient comfort should be assessed regularly, non-pharmacological interventions taken into account and the use of sedatives and analgesics adapted to the individual requirements of the patient.

Immediate interruption of sedation compared with usual sedation care in critically ill postoperative patients (SOS-Ventilation): a randomised, parallel-group clinical trial.

Science.gov (United States)

Chanques, Gerald; Conseil, Matthieu; Roger, Claire; Constantin, Jean-Michel; Prades, Albert; Carr, Julie; Muller, Laurent; Jung, Boris; Belafia, Fouad; Cissé, Moussa; Delay, Jean-Marc; de Jong, Audrey; Lefrant, Jean-Yves; Futier, Emmanuel; Mercier, Grégoire; Molinari, Nicolas; Jaber, Samir

2017-10-01

Avoidance of excessive sedation and subsequent prolonged mechanical ventilation in intensive care units (ICUs) is recommended, but no data are available for critically ill postoperative patients. We hypothesised that in such patients stopping sedation immediately after admission to the ICU could reduce unnecessary sedation and improve patient outcomes. We did a randomised, parallel-group, clinical trial at three ICUs in France. Stratified randomisation with minimisation (1:1 via a restricted web platform) was used to assign eligible patients (aged ≥18 years, admitted to an ICU after abdominal surgery, and expected to require at least 12 h of mechanical ventilation because of a critical illness defined by a Sequential Organ Failure Assessment score >1 for any organ, but without severe acute respiratory distress syndrome or brain injury) to usual sedation care provided according to recommended practices (control group) or to immediate interruption of sedation (intervention group). The primary outcome was the time to successful extubation (defined as the time from randomisation to the time of extubation [or tracheotomy mask] for at least 48 h). All patients who underwent randomisation (except for those who were excluded after randomisation) were included in the intention-to-treat analysis. This study is registered with ClinicalTrials.gov, number NCT01486121. Between Dec 2, 2011, and Feb 27, 2014, 137 patients were randomly assigned to the control (n=68) or intervention groups (n=69). In the intention-to-treat analysis, time to successful extubation was significantly lower in the intervention group than in the control group (median 8 h [IQR 4-36] vs 50 h [29-93], group difference -33·6 h [95% CI -44·9 to -22·4]; p<0·0001). The adjusted hazard ratio was 5·2 (95% CI 3·1-8·8, p<0·0001). Immediate interruption of sedation in critically ill postoperative patients with organ dysfunction who were admitted to the ICU after abdominal surgery improved outcomes compared

A Conscious Sedation Protocol for Videolaryngostroboscopy in Pediatric Patients

Directory of Open Access Journals (Sweden)

Samantha Anne

2010-01-01

Full Text Available Objective. To determine best sedation protocol for videolaryngostroboscopy in children unable to tolerate non-sedated evaluation. Materials and Methods. Consecutive case series of 10 children with voice disturbances, unable to tolerate nonsedated videolaryngostroboscopy at an academic tertiary care children’s hospital. Flexible fiberoptic videolaryngostroboscopy was performed and interpreted by pediatric otolaryngologist and speech and language pathologist. Sedation was administered with newly described protocol that allowed functional portion of evaluation. Main Outcome Measures: ability to follow commands and tolerate flexible fiberoptic videolaryngostroboscopy. Secondary Outcome Measures: total phonation time, complications, need for subsequent videolaryngostroboscopic attempts, clinical outcomes, and follow-up. Results. 10 children underwent procedure under conscious sedation. 9/10 children were able to perform simple tasks and maintain adequate phonation time to complete stroboscopic exam. 1/10 patients failed to complete exam because of crying during entire exam. Mean exam time was 2 minutes 52 seconds (SD 86 seconds, phonation time is 1 minute 44 seconds (SD 60 seconds, and number of tasks completed was 10.5 (SD 8.6. Conclusions. Conscious sedation for videolaryngostroboscopy can be safely and effectively performed in children unable to comply with nonsedated examination. Such studies provide valuable diagnostic information to make a diagnosis and to devise a treatment plan.

Optimization of instant dalia dessert pre-mix production by using response surface methodology.

Science.gov (United States)

Jha, Alok; Shalini, B N; Patel, Ashok Ambalal; Singh, Mithilesh; Rasane, Prasad

2015-02-01

Dalia, a wheat-based, particulate containing dairy dessert is popularly consumed as a breakfast food and is also considered as a health food. Though popular throughout Northern parts of the country, its limited shelf-life even under refrigeration imposes severe restrictions on its organized manufacture and marketing. In order to promote dalia dessert as a marketable product, in the present study, a process was developed for manufacture of instant dalia pre-mix, as a dry product with long shelf-life, which could be attractively packaged and easily reconstituted for consumption. During the investigation, the effect of different levels of milk solids and wheat solids was studied on dalia pre-mix quality by employing a central composite rotatable design (CCRD). The suggested formulation had 17.82 % milk solids and 2.87 % wheat solids. This formulation was found to be most appropriate for manufacture of instant dalia pre-mix with predicted sensory scores (Max. 100) of 85.35, 41.98 and 67.27 for mouthfeel, consistency and flavor, respectively; the viscosity of the product was 941.0 cp.

A parallel adaptive mesh refinement algorithm for predicting turbulent non-premixed combusting flows

International Nuclear Information System (INIS)

Gao, X.; Groth, C.P.T.

2005-01-01

A parallel adaptive mesh refinement (AMR) algorithm is proposed for predicting turbulent non-premixed combusting flows characteristic of gas turbine engine combustors. The Favre-averaged Navier-Stokes equations governing mixture and species transport for a reactive mixture of thermally perfect gases in two dimensions, the two transport equations of the κ-ψ turbulence model, and the time-averaged species transport equations, are all solved using a fully coupled finite-volume formulation. A flexible block-based hierarchical data structure is used to maintain the connectivity of the solution blocks in the multi-block mesh and facilitate automatic solution-directed mesh adaptation according to physics-based refinement criteria. This AMR approach allows for anisotropic mesh refinement and the block-based data structure readily permits efficient and scalable implementations of the algorithm on multi-processor architectures. Numerical results for turbulent non-premixed diffusion flames, including cold- and hot-flow predictions for a bluff body burner, are described and compared to available experimental data. The numerical results demonstrate the validity and potential of the parallel AMR approach for predicting complex non-premixed turbulent combusting flows. (author)

An Investigation of a Hybrid Mixing Timescale Model for PDF Simulations of Turbulent Premixed Flames

Science.gov (United States)

Zhou, Hua; Kuron, Mike; Ren, Zhuyin; Lu, Tianfeng; Chen, Jacqueline H.

2016-11-01

Transported probability density function (TPDF) method features the generality for all combustion regimes, which is attractive for turbulent combustion simulations. However, the modeling of micromixing due to molecular diffusion is still considered to be a primary challenge for TPDF method, especially in turbulent premixed flames. Recently, a hybrid mixing rate model for TPDF simulations of turbulent premixed flames has been proposed, which recovers the correct mixing rates in the limits of flamelet regime and broken reaction zone regime while at the same time aims to properly account for the transition in between. In this work, this model is employed in TPDF simulations of turbulent premixed methane-air slot burner flames. The model performance is assessed by comparing the results from both direct numerical simulation (DNS) and conventional constant mechanical-to-scalar mixing rate model. This work is Granted by NSFC 51476087 and 91441202.

Performing bone marrow biopsies with or without sedation: a comparison.

Science.gov (United States)

Giannoutsos, I; Grech, H; Maboreke, T; Morgenstern, G

2004-06-01

Although intravenous sedation (ISED) in addition to a local anaesthetic (LA) is commonly used in the performance of a bone marrow aspirate and trephine (BMAT), it is not clear under what circumstances and in which way sedation may be most beneficial. In this study, information was gathered using a questionnaire, from 112 patients shortly after undergoing BMAT; the duration of the procedures and the length of the biopsy cores were measured and any complications noted. Most patients (68%) chose to receive LA only, and almost all (74/76) were happy with their decision. Patients who received sedation gave lower pain scores than patients receiving LA only (1 vs. 3) and were found to have lower levels of apprehension at the thought of having a repeat procedure. Patients having a repeat BMAT showed a slightly increased preference for having sedation compared with patients who were undergoing it for the first time. There is some concern that guidelines regarding the use of ISED for procedures other than BMAT are not always adhered to, and current practice may be best revealed by a large-scale audit of sedation practice for the performance of BMAT. Patients should be given the choice of having ISED if the appropriate resources are available, but in most cases the additional small risk of receiving sedation can be avoided.

A systematic literature review on the ethics of palliative sedation: an update (2016).

Science.gov (United States)

Henry, Blair

2016-09-01

Palliative sedation has been the subject of intensive debate since its first appearance in 1990. In a 2010 review of palliative sedation, the following areas were identified as lacking in consensus: inconsistent terminology, its use in nonphysical suffering, the ongoing experience of distress, and concern that the practice of palliative sedation may hasten death. This review looks at the literature over the past 6 years and provides an update on these outstanding concerns. Good clinical guidelines and policies are still required to address issues of emotional distress and waylay concerns that palliative sedation hastens death. The empirical evidence suggests some movement toward consensus on the practice of palliative sedation. However, a continued need exists for evidence-informed practice guidelines, education, and research to support the ethical practice of palliative sedation at the end of life. Until that time, clinicians are advised to adopt a framework or guideline that has been expert driven to ensure consistent and ethical use of palliative sedation at the end of life.

Sedation with detomidine and acepromazine influences the endoscopic evaluation of laryngeal function in horses.

Science.gov (United States)

Lindegaard, C; Husted, L; Ullum, H; Fjeldborg, J

2007-11-01

Endoscopy of the upper airways of horses is used as a diagnostic tool and at purchase examinations. On some occasions it is necessary to use sedation during the procedure and it is often speculated that the result of the examination might be influenced due to the muscle-relaxing properties of the most commonly used sedatives. To evaluate the effect of detomidine (0.01 mg/kg bwt) and acepromazine (0.05 mg/kg bwt) on the appearance of symmetry of rima glottidis, ability to abduct maximally the arytenoid cartilages and the effect on recurrent laryngeal neuropathy (RLN) grade. Forty-two apparently normal horses underwent endoscopic examination of the upper airways on 3 different occasions, under the influence of 3 different treatments: no sedation (control), sedation with detomidine and sedation with acepromazine. All examinations were performed with a minimum of one week apart. The study was performed as an observer-blind cross-over study. Sedation with detomidine had a significant effect on the RLN grading (OR = 2.91) and ability maximally to abduct the left arytenoid cartilages (OR = 2.91). Sedation with acepromazine resulted in OR = 2.43 for the RLN grading and OR = 2.22 for the ability to abduct maximally. The ability to abduct maximally the right arytenoid cartilage was not altered. Sedating apparently healthy horses with detomidine or acepromazine significantly impairs these horses' ability to abduct fully the left but not the right arytenoid cartilage. This resulted in different diagnosis with respect to RLN when comparing sedation to no sedation. Since the ability to abduct the right arytenoid cartilage fully is not altered by sedation, it is speculated that horses changing from normal to abnormal laryngeal function when sedated, might be horses in an early stage of the disease. To confirm or reject these speculations, further studies are needed. Until then sedation during endoscopy should be used with care.

Who is referred for sedation for dentistry and why?

Science.gov (United States)

Boyle, C A; Newton, T; Milgrom, P

2009-03-28

To assess referrals to sedation, examining dental anxiety and background of patients, and compare these characteristics to those referred to a restorative dentistry clinic. Descriptive, cross sectional survey. Subjects were 100 consecutive new patients in sedation and special care and 50 new patients in restorative dentistry at Guy's and St Thomas NHS Foundation Trust. A questionnaire included demographics, self-reported oral health and dental attendance, and dental fear. Information from the patients records was taken: ASA classification, previous sedation or general anaesthesia, alcohol and tobacco use, and medications. The best predictors of referral were dental anxiety level and an irregular attendance. The most important fears were seeing, hearing and feeling the vibrations of the dental drill, and the perception of an accelerated heart rate. Other factors such as general, mental and dental health and alcohol use were related to referral but less important. Referral is consistent with the goal of the sedation clinic to see anxious patients. Referring general practitioners are able to identify these patients.

Consultation with specialist palliative care services in palliative sedation: considerations of Dutch physicians.

Science.gov (United States)

Koper, Ian; van der Heide, Agnes; Janssens, Rien; Swart, Siebe; Perez, Roberto; Rietjens, Judith

2014-01-01

Palliative sedation is considered a normal medical practice by the Royal Dutch Medical Association. Therefore, consultation of an expert is not considered mandatory. The European Association of Palliative Care (EAPC) framework for palliative sedation, however, is more stringent: it considers the use of palliative sedation without consulting an expert as injudicious and insists on input from a multi-professional palliative care team. This study investigates the considerations of Dutch physicians concerning consultation about palliative sedation with specialist palliative care services. Fifty-four physicians were interviewed on their most recent case of palliative sedation. Reasons to consult were a lack of expertise and the view that consultation was generally supportive. Reasons not to consult were sufficient expertise, the view that palliative sedation is a normal medical procedure, time pressure, fear of disagreement with the service and regarding consultation as having little added value. Arguments in favour of mandatory consultation were that many physicians lack expertise and that palliative sedation is an exceptional intervention. Arguments against mandatory consultation were practical obstacles that may preclude fulfilling such an obligation (i.e. lack of time), palliative sedation being a standard medical procedure, corroding a physician's responsibility and deterring physicians from applying palliative sedation. Consultation about palliative sedation with specialist palliative care services is regarded as supportive and helpful when physicians lack expertise. However, Dutch physicians have both practical and theoretical objections against mandatory consultation. Based on the findings in this study, there seems to be little support among Dutch physicians for the EAPC recommendations on obligatory consultation.

Effect of Different Routes of Vitamin/Mineral premix Administration ...

African Journals Online (AJOL)

An experiment was conducted to determine the best route of vitamin/mineral premix administration to broilers using a completely randomized design. The routes of administrations were through formulated diets, daily in drinking water, and daily mixing in feed ration. Histological examination of the liver did not reveal any ...

Structure of Unsteady Partially Premixed Flames and the Existence of State Relationships

Directory of Open Access Journals (Sweden)

Suresh K. Aggarwal

2009-09-01

Full Text Available In this study, we examine the structure and existence of state relationships in unsteady partially premixed flames (PPFs subjected to buoyancy-induced and external perturbations. A detailed numerical model is employed to simulate the steady and unsteady two-dimensional PPFs established using a slot burner under normal and zero-gravity conditions. The coflow velocity is parametrically varied. The methane-air chemistry is modeled using a fairly detailed mechanism that contains 81 elementary reactions and 24 species. Validation of the computational model is provided through comparisons of predictions with nonintrusive measurements. The combustion proceeds in two reaction zones, one a rich premixed zone and the other a nonpremixed zone. These reaction zones are spatially separated, but involve strong interactions between them due to thermochemistry and scalar transport. The fuel is mostly consumed in the premixed zone to produce CO and H2, which are transported to and consumed in the nonpremixed zone. The nonpremixed zone in turn provides heat and H-atoms to the premixed zone. For the range of conditions investigated, the zero-g partially premixed flames exhibit a stable behavior and a remarkably strong resistance to perturbations. In contrast, the corresponding normal-gravity flames exhibit oscillatory behavior at low coflow velocities but a stable behavior at high coflow velocities, and the behavior can be explained in terms of a global and convective instabilities. The effects of coflow and gravity on the flames are characterized through a parameter VR, defined as the ratio of coflow velocity to jet velocity. For VR ≤ 1 (low coflow velocity regime, the structures of both 0- and 1-g flames are strongly sensitive to changes in VR, while they are only mildly affected by coflow in the high coflow velocity regime (VR > 1. In addition, the spatio-temporal characteristics of the 0- and 1-g flames are markedly different in the first regime, but are

Effects of midazolam and morphine on cerebral oxygenation and hemodynamics in ventilated premature infants.

NARCIS (Netherlands)

Velden, A.A.E.M. van der; Hopman, J.C.W.; Klaessens, J.H.G.M.; Feuth, A.B.; Sengers, R.C.A.; Liem, K.D.

2006-01-01

BACKGROUND: Midazolam sedation and morphine analgesia are commonly used in ventilated premature infants. OBJECTIVES: To evaluate the effects of midazolam versus morphine infusion on cerebral oxygenation and hemodynamics in ventilated premature infants. METHODS: 11 patients (GA 26.6-33.0 weeks, BW

Changes in resting neural connectivity during propofol sedation.

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Emmanuel A Stamatakis

2010-12-01

Full Text Available The default mode network consists of a set of functionally connected brain regions (posterior cingulate, medial prefrontal cortex and bilateral parietal cortex maximally active in functional imaging studies under "no task" conditions. It has been argued that the posterior cingulate is important in consciousness/awareness, but previous investigations of resting interactions between the posterior cingulate cortex and other brain regions during sedation and anesthesia have produced inconsistent results.We examined the connectivity of the posterior cingulate at different levels of consciousness. "No task" fMRI (BOLD data were collected from healthy volunteers while awake and at low and moderate levels of sedation, induced by the anesthetic agent propofol. Our data show that connectivity of the posterior cingulate changes during sedation to include areas that are not traditionally considered to be part of the default mode network, such as the motor/somatosensory cortices, the anterior thalamic nuclei, and the reticular activating system.This neuroanatomical signature resembles that of non-REM sleep, and may be evidence for a system that reduces its discriminable states and switches into more stereotypic patterns of firing under sedation.

Experience with Conscious sedation for Oocyte Retrieval in Nigeria

African Journals Online (AJOL)

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The aim of this study was to assess clients' pain experience, acceptance of conscious sedation and correlates of pain during oocyte retrieval ... Conscious sedation and analgesia are one of several methods used to relieve pain during oocyte retrieval in. IVF procedures. .... relieves anxiety and reduces the patient's memory.

Sleep and Sedative States Induced by Targeting the Histamine and Noradrenergic Systems

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Xiao Yu

2018-01-01

Full Text Available Sedatives target just a handful of receptors and ion channels. But we have no satisfying explanation for how activating these receptors produces sedation. In particular, do sedatives act at restricted brain locations and circuitries or more widely? Two prominent sedative drugs in clinical use are zolpidem, a GABAA receptor positive allosteric modulator, and dexmedetomidine (DEX, a selective α2 adrenergic receptor agonist. By targeting hypothalamic neuromodulatory systems both drugs induce a sleep-like state, but in different ways: zolpidem primarily reduces the latency to NREM sleep, and is a controlled substance taken by many people to help them sleep; DEX produces prominent slow wave activity in the electroencephalogram (EEG resembling stage 2 NREM sleep, but with complications of hypothermia and lowered blood pressure—it is used for long term sedation in hospital intensive care units—under DEX-induced sedation patients are arousable and responsive, and this drug reduces the risk of delirium. DEX, and another α2 adrenergic agonist xylazine, are also widely used in veterinary clinics to sedate animals. Here we review how these two different classes of sedatives, zolpidem and dexmedetomideine, can selectively interact with some nodal points of the circuitry that promote wakefulness allowing the transition to NREM sleep. Zolpidem enhances GABAergic transmission onto histamine neurons in the hypothalamic tuberomammillary nucleus (TMN to hasten the transition to NREM sleep, and DEX interacts with neurons in the preoptic hypothalamic area that induce sleep and body cooling. This knowledge may aid the design of more precise acting sedatives, and at the same time, reveal more about the natural sleep-wake circuitry.

Comparison of Procedural Sedation for the Reduction of Dislocated Total Hip Arthroplasty

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Jonathan E. dela Cruz

2014-02-01

Full Text Available Introduction: Various types of sedation can be used for the reduction of a dislocated total hip arthroplasty. Traditionally, an Opiate/Benzodiazepine combination has been employed. The use of other pharmacologic agents, such as Etomidate and Propofol, has more recently gained popularity. Currently no studies directly comparing these sedation agents have been carried out. The purpose of this study is to compare differences in reduction and sedation outcomes including recovery times of these three different sedation agents. Methods: A retrospective chart review was performed examining 198 patient’s charts who presented with dislocated total hip arthroplasty at two academic affiliated medical centers. The patients were organized into groups according to the type of sedation agent used during their reduction. The percentages of reduction and sedation complications were calculated along with overall recovery times. Reduction complications included fracture, skin or neurovascular injury, and failure of reduction requiring general anesthesia. Sedation complications included use of bag-valve mask and artificial airway, intubation, prolonged recovery, use of a reversal agent, and inability to achieve sedation. The data were then compared for each sedation agent. Results: The reduction complications rates found were 8.7% in the Propofol group, 24.68% in the Etomidate, and 28.85% in the Opiate/Benzodiazepine groups. The reduction complication rate in the Propofol group was significantly different than those of the other two agents (p≤0.01. Sedation complications were found to happen 7.25% of the time in the Propofol group, 11.69% in the Etomidate group, and 21.25% in the Opiate/ Benzodiazepine group with Propofol having complication rates significantly different than that of the Opiate/Benzodiazepine group (p=0.02. Average lengths of recovery were 25.17 minutes for Propofol, 30.83 minutes for Etomidate, and 44.35 minutes for Opiate/ Benzodiazepine with

The application of Flamelet Generated Manifolds in partailly-premixed flames

NARCIS (Netherlands)

Ramaekers, W.J.S.; Albrecht, B.A.; Oijen, van J.A.; Goey, de L.P.H.; Eggels, R.L.G.M.

2005-01-01

To reduce harmful emissions numerical models are developed to simulate combustion processes in engineering applications. In this paper a model for partially-premixed combustion used in Reynolds Averaged Navier-Stokes Simulations (RANS) is presented. A flamelet approach combined with a Probability

Determinants of the administration of continuous palliative sedation: a systematic review.

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van Deijck, Rogier H P D; Hasselaar, Jeroen G J; Verhagen, Stans C A H H V M; Vissers, Kris C P; Koopmans, Raymond T C M

2013-12-01

Little is known about the determining factors related to the administration of continuous palliative sedation. Knowledge of these determinants may assist physicians in identifying patients who are at high risk of developing refractory symptoms, enable physicians to inform patients, and optimize close monitoring. The aim of this systematic review was to identify determinants of the administration of continuous palliative sedation. A systematic review of PubMed, EMBASE, and CINAHL was performed to identify English, Dutch, and German language papers published from January 1990 through April 2011. Inclusion was based on the following criteria: patient-based research on continuous palliative sedation, studies investigating determinants of palliative sedation and/or comparison between sedated and nonsedated cohorts, and studies using multivariate analyses and of fair to good or good methodological quality. In total, eight papers were reviewed. The following nine factors were found to be associated with the administration of continuous palliative sedation: younger age, male sex, having cancer, feelings of hopelessness, dying in a hospital, living in a Dutch speaking community setting, very nonreligious or extremely nonreligious physicians, physicians working in "other hospital" specialties, and physicians in favor of assisted death. Given the variation in study designs and the limitations of the included studies, the outcomes should be interpreted carefully. Further research is needed, particularly regarding factors that can be influenced and that may alter the course of a patient's symptoms and the patient's eventual need for palliative sedation.

Premixer Design for High Hydrogen Fuels

Energy Technology Data Exchange (ETDEWEB)

Benjamin P. Lacy; Keith R. McManus; Balachandar Varatharajan; Biswadip Shome

2005-12-16

This 21-month project translated DLN technology to the unique properties of high hydrogen content IGCC fuels, and yielded designs in preparation for a future testing and validation phase. Fundamental flame characterization, mixing, and flame property measurement experiments were conducted to tailor computational design tools and criteria to create a framework for predicting nozzle operability (e.g., flame stabilization, emissions, resistance to flashback/flame-holding and auto-ignition). This framework was then used to establish, rank, and evaluate potential solutions to the operability challenges of IGCC combustion. The leading contenders were studied and developed with the most promising concepts evaluated via computational fluid dynamics (CFD) modeling and using the design rules generated by the fundamental experiments, as well as using GE's combustion design tools and practices. Finally, the project scoped the necessary steps required to carry the design through mechanical and durability review, testing, and validation, towards full demonstration of this revolutionary technology. This project was carried out in three linked tasks with the following results. (1) Develop conceptual designs of premixer and down-select the promising options. This task defined the ''gap'' between existing design capabilities and the targeted range of IGCC fuel compositions and evaluated the current capability of DLN pre-mixer designs when operated at similar conditions. Two concepts (1) swirl based and (2) multiple point lean direct injection based premixers were selected via a QFD from 13 potential design concepts. (2) Carry out CFD on chosen options (1 or 2) to evaluate operability risks. This task developed the leading options down-selected in Task 1. Both a GE15 swozzle based premixer and a lean direct injection concept were examined by performing a detailed CFD study wherein the aerodynamics of the design, together with the chemical kinetics of the

The use of dexmedetomidine in intensive care sedation

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Massimo Antonelli

2013-05-01

Full Text Available The goals and recommendations for ICU (Intensive Care Unit patients’ sedation and analgesia should be to have adequately sedated patients who are calm and arousal, so that they can guarantee a proper evaluation and an adequate control of pain. This way, it is also possible to perform their neurological evaluation, preserving intellectual faculties and helping them in actively participating to their care. Dexmedetomidine is a selective alpha-2 receptor agonist, member of theraputical cathegory: “other hypnotics and sedatives” (ATC: N05CM18. Dexmedetomidine is recommended for the sedation of adult ICU patients who need a sedation level not deeper than arousal in response to verbal stimulation (corresponding to Richmond Agitation-Sedation Scale 0 to -3. After the EMA approval, some European government authorities have elaborated HTA on dexmedetomidine, based on clinical evidence derived from Prodex and Midex trials. Dexmedetomidine resulted to be as effective as propofol and midazolam in maintaining the target depth of sedation in ICU patients. The mean duration of mechanical ventilation with dexmedetomidine was numerically shorter than with propofol and significantly shorter than with midazolam. The resulting favourable economic profile of dexmedetomidine supported the clinical use in ICU. Dexmedetomidine seems to provide clinical benefits due to the reduction of mechanical ventilation and ventilator weaning duration. Within the present review, an economic analysis of costs associated to the use of dexmedetomidine was therefore performed also in the Italian care setting. Thus, four different analyses were carried out based on the quantification of the total number of days in ICU, the time spent on mechanical ventilation, the weighted average number of days with mechanical ventilation or not and TISS points (Therapeutic Intervention Scoring System. Despite the incremental cost for drug therapy associated with dexmedetomidine, a reduction of

Linear Stability Analysis of Laminar Premixed Fuel-Rich Double-Spray Flames

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Noam Weinberg

2014-03-01

Full Text Available This paper considers the stability of a double-spray premixed flame formed when both fuel and oxidizer are initially present in the form of sprays of evaporating liquid droplets. To simplify the inherent complexity that characterizes the analytic solution of multi-phase combustion processes, the analysis is restricted to fuel-rich laminar premixed double-spray flames, and assumes a single-step global chemical reaction mechanism. Steady-state solutions are obtained and the sensitivity of the flame temperature and the flame propagating velocity to the initial liquid fuel and/or oxidizer loads are established. The stability analysis revealed an increased proneness to cellular instability induced by the presence of the two sprays, and for the fuel-rich case considered here the influence of the liquid oxidizer was found to be more pronounced than that of the liquid fuel. Similar effects were noted for the neutral pulsating stability boundaries. The impact of unequal latent heats of vaporization is also investigated and found to be in keeping with the destabilizing influence of heat loss due to droplet evaporation. It should be noted that as far as the authors are aware no experimental evidence is available for (at least validation of the predictions. However, they do concur in a general and reasonable fashion with independent experimental evidence in the literature of the behavior of single fuel spray laminar premixed flames.

[A first step towards safer sedation and analgesia: A systematic evaluation of outcomes and level of sedation and analgesia in the mechanically ventilated critically ill patient].

Science.gov (United States)

Frade-Mera, M J; Regueiro-Díaz, N; Díaz-Castellano, L; Torres-Valverde, L; Alonso-Pérez, L; Landívar-Redondo, M M; Muñoz-Pasín, R; Terceros-Almanza, L J; Temprano-Vázquez, S; Sánchez-Izquierdo-Riera, J Á

Safe analgesia and sedation strategies are necessary in order to avoid under or over sedation, as well as improving the comfort and safety of critical care patients. To compare and contrast a multidisciplinary protocol of systematic evaluation and management of analgesia and sedation in a group of critical care patients on mechanical ventilation with the usual procedures. A cohort study with contemporary series was conducted in a tertiary care medical-surgical ICU February to November during 2013 and 2014. The inclusion criteria were mechanical ventilation ≥ 24h and use of sedation by continuous infusion. Sedation was monitored using the Richmond agitation-sedation scale or bispectral index, and analgesia were measured using the numeric rating scale, or behavioural indicators of pain scale. The study variables included; mechanical ventilation time, weaning time, ventilation support time, artificial airway time, continuous sedative infusion time, daily dose and frequency of analgesic and sedative drug use, hospital stay, and ICU and hospital mortality, Richmond agitation-sedation scale, bispectral index, numeric rating scale, and behavioural indicators of pain scale measurements. Kruskal Wallis and Chi 2 , and a significance of p<.05 were used. The study included 153 admissions, 75 pre-intervention and 78 post-intervention, with a mean age of 55.7±13 years old, and 67% men. Both groups showed similarities in age, reason for admission, and APACHE. There were non-significant decreases in mechanical ventilation time 4 (1.4-9.2) and 3.2 (1.4-8.1) days, respectively; p= 0.7, continuous sedative infusion time 6 (3-11) and 5 (3-11) days; p= 0.9, length of hospital stay 29 (18-52); 25 (14-41) days; p= 0.1, ICU mortality (8 vs. 5%; p= 0.4), and hospital mortality (10.6 vs. 9.4%: p= 0.8). Daily doses of midazolam and remifentanil decreased 347 (227-479) mg/day; 261 (159-358) mg/day; p= 0.02 and 2175 (1427-3285) mcg/day; 1500 (715-2740) mcg/day; p= 0.02, respectively. There

Why intravenous moderate sedation should be taught in graduate endodontic programs.

Science.gov (United States)

Montagnese, Thomas Anthony

2012-03-01

The purpose of this opinion article is to present reasons why intravenous moderate sedation should be taught in graduate endodontic programs. Access to oral health care is an area of much interest and concern, but some patients are unable to get endodontic care because they have special needs. Special needs can refer to patients who fear dentistry itself and other aspects of dental treatment. A variety of phobias and medical, developmental, and physical conditions can make it difficult for some patients to tolerate the endodontic care they need and want. Moderate sedation can help many of these patients. Endodontists in general are not trained to provide intravenous moderate sedation. By incorporating intravenous moderate sedation into endodontic practice, many of these patients can be treated. The first step in achieving this goal is to add intravenous moderate sedation training to graduate endodontic programs. The long-term effect will be to make specialty endodontic care available to more people.

Superiority of split dose midazolam as conscious sedation for outpatient colonoscopy.

Science.gov (United States)

Lee, Hyuk; Kim, Jeong Hwan

2009-08-14

To elucidate the efficacy and safety of a split dose of midazolam in combination with meperidine for colonoscopy. Eighty subjects undergoing outpatient colonoscopy were randomly assigned to group A or B. Group A (n = 40) received a split dose of midazolam in combination with meperidine. Group B (n = 40) received a single dose of midazolam in combination with meperidine. Outcome measurements were level of sedation, duration of sedation and recovery, degree of pain and satisfaction, procedure-related memory, controllability, and adverse events. Group A had a lower frequency of significant hypoxemia (P = 0.043) and a higher sedation score on withdrawal of the endoscope from the descending colon than group B (P = 0.043). Group B recovered from sedation slightly sooner than group A (P memory, except insertion-related memory, were lower in group A one week after colonoscopic examination (P = 0.018 and P sedation status during colonoscopic examination and a reduction in procedure-related pain and memory, but resulted in longer recovery time.

Minimal and moderate oral sedation in the adult special needs patient.

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Coke, John M; Edwards, Michael D

2009-04-01

Oral minimal/moderate sedation can be an effective tool to aid in the dental management of adult special needs patients. Specific sedative drugs must be chosen by the dentist that can be used safely and effectively on these patients. This article focuses on a select number of these drugs, specific medical and pharmacologic challenges presented by adult special needs patients, and techniques to safely administer oral minimal and moderate sedation.

Drug-induced amnesia is a separate phenomenon from sedation: electrophysiologic evidence.

Science.gov (United States)

Veselis, R A; Reinsel, R A; Feshchenko, V A

2001-10-01

Sedative-hypnotic drugs not only increase sedation, but also impair memory as serum concentration increases. These drugs also produce profound changes in the auditory event-related potential (ERP). The ability of various ERP components to predict changes in sedation and memory produced by various drugs was tested. Sixty-five healthy volunteers randomly received intravenous placebo, midazolam, propofol, thiopental, fentanyl with ondansetron, or ondansetron alone at five different stable target concentrations (three increasing, two decreasing) using a computer-controlled infusion pump to produce varying degrees of sedation without loss of consciousness. ERPs were recorded while volunteer participants detected a deviant auditory stimulus and made a button-press response to a target tone (standard oddball paradigm, 80:20 ratio, to elicit a P3 response). At each target concentration, volunteers learned a list of 16 words. The predictive probabilities (Pk) of various ERP components were determined for word recognition at the end of the day (memory) and log reaction time to the deviant stimulus (sedation). The N2 latency of the ERP consistently predicted log reaction time in all groups (Pk +/- SE from 0.58 +/- 0.04 to 0.71 +/- 0.04). The N2P3 amplitude of the ERP was the best predictor of memory performance for midazolam (Pk, 0.63 +/- 0.04), propofol (Pk, 0.62 +/- 0.05), and thiopental (Pk, 0.66 +/- 0.04). There was a differential ability to predict memory performance from sedation for midazolam and propofol. Midazolam and propofol affect memory differentially from their sedative effects, and these are indexed by specific components of the auditory ERP. These components of the ERP are associated with specific, but not necessarily unique, neuroanatomic structures. Thus, these drugs act by additional mechanisms beyond general central nervous system depression to produce the effects of sedation and memory impairment.

Survey on sedation in paediatric dentistry: a global perspective.

Science.gov (United States)

Wilson, Stephen; Alcaino, Eduardo A

2011-09-01

Paediatric dentists receive training in sedation during their advanced education training, but evidence suggests that this training varies widely. The purpose of this study was to survey members of the International Association of Paediatric Dentistry (IAPD) and the European Academy of Paediatric Dentistry (EAPD) on their opinion on pharmacological and other behavioural management techniques and their training related to provision of oral health care of paediatric patients in the dental setting. A request was made for access to the IAPD and EAPD membership email addresses. The responses were recorded anonymously and data uploaded into spss (version 9) and analysed using descriptive analysis and chi-square with and without tabulation processes. A total of 311 respondents of 1973 targeted individuals answered the survey. The response rate was 16%. The majority of the respondents came from the continent of Europe, Asia, and the Americas. The most frequent type of sedation was general anaesthesia (52% of the respondents), followed by nitrous oxide (46%) and then oral sedation (44%). At least 91% of the respondents indicated that they were interested in the development of continuing education on the topic of sedation. Paediatric dentists around the world use relatively few behaviour management techniques, including pharmacological management. There is a definite interest in continuing education in the area of sedation. The Authors. International Journal of Paediatric Dentistry © 2011 BSPD, IAPD and Blackwell Publishing Ltd.

'Targeting' sedation: the lived experience of the intensive care nurse.

Science.gov (United States)

Everingham, Kirsty; Fawcett, Tonks; Walsh, Tim

2014-03-01

To discuss the findings from a phenomenological study that provides insights into the intensive care nurses' 'world' following changes in the sedation management of patients in an intensive care unit. Intensive care sedation practices have undergone significant changes. Patients, where possible, are now managed on lighter levels of sedation, often achieved through the performance of sedation holds (SHs). The performance of SHs is normally carried out by the bedside nurse but compliance is reported to be poor. There has been little exploration of the nurses' experiences of these changes and the implications of SHs and subsequent wakefulness on their delivery of care. Following ethical approval, 16 intensive care nurses, experienced and inexperienced, from within a general intensive care unit. A Heideggerian phenomenological approach was used. Data collection consisted of interviews guided by an aide memoir and a framework adapted from Van Manen informed the analysis. The findings reveal new insights into the world of the intensive care nurse in the light of the changes to sedation management. They demonstrate that there have been unforeseen outcomes from well-intentioned initiatives to improve the quality of patients' care. There were implications from the changes introduced for the nurses care delivery. The main themes that emerged were 'working priorities' and 'unintended consequences', in turn revealing embedded tensions between evidence-based targets and holistic care. Intensive care nurses find that the current approach to the changes in sedation management can threaten their professional obligation and personal desire to provide holistic care. The 'targeted' approach by healthcare organisations is perceived to militate against the patient-centred care they want to deliver. Sedation management is complex and needs further consideration particularly the potential constraints 'target-led' care has on nursing practice. © 2013 Blackwell Publishing Ltd.

Subtypes of adolescent sedative/anxiolytic misusers: A latent profile analysis.

Science.gov (United States)

Hall, Martin T; Howard, Matthew O; McCabe, Sean Esteban

2010-10-01

Few empirically-based taxonomies of nonmedical prescription drug misusers have been published. This study used latent profile analysis (LPA) to identify classes of adolescent sedative/anxiolytic misusers. Interviews assessing substance use, psychiatric symptoms, antisocial traits/behavior, and traumatic life experiences were conducted with 723 Missouri youth in residential care for antisocial behavior. Sedative/anxiolytic misusers (N=247) averaged 15.8 (S.D.=1.1) years of age; a majority were male (83.8%), White (70.0%), and resided in rural/small town areas (53.8%). LPA yielded a three-class solution. Class 1 (59.1%) was comprised of youth with significantly lower levels of currently distressing psychiatric symptoms, fewer lifetime traumatic experiences, less problematic substance use histories, less frequent antisocial behavior, and less impulsivity than youth in Classes 2 and 3. Class 2 (11.3%) youth had high levels of currently distressing psychiatric symptoms and more frequent antisocial behavior compared to youth in Classes 1 and 3. Class 3 (29.5%) youth evidenced levels of psychiatric and behavioral problems that were intermediate to those of Class 1 and 2 youth. Frequency of sedative/anxiolytic misuse was significantly higher in Classes 2 and 3 compared to Class 1. Members of Class 2 and Class 3 also had the highest levels of psychiatric symptoms for which sedatives/anxiolytics are commonly prescribed. Significant differences between classes were observed across a range of health, mental health, personality, and behavioral variables. Adolescents who misused prescription sedatives/anxiolytics evidenced significant heterogeneity across measures of psychiatric and behavioral dysfunction. Youth with comparatively high levels of anxiety and depression reported significantly more intensive sedative/anxiolytic misuse than their counterparts and may be at high risk for sedative/anxiolytic abuse and dependence. 2010 Elsevier Ltd. All rights reserved.

Efficacy of Ketamine in Pediatric Sedation Dentistry: A Systematic Review.

Science.gov (United States)

Oh, Samuel; Kingsley, Karl

2018-05-01

Ketamine has been used as a safe and effective sedative to treat adults and children exhibiting high levels of anxiety or fear during dental treatment. Pediatric dentistry often involves patients with high levels of anxiety and fear and possibly few positive dental experiences. Patient management can involve behavioral approaches, as well as the use of sedation or general anesthesia with a variety of agents, including midazolam, diazepam, hydroxyzine, meperidine, and ketamine. The aim of this study was to investigate the clinical efficacy of ketamine use in pediatric sedation dentistry through systematic review and analysis. A systematic review of publications between 1990 and 2015 was conducted using PubMed and MEDLINE databases maintained by the US National Library of Medicine and the National Institutes of Health. The keywords used were (ketamine) AND (dental OR dentistry) AND (sedation). The abstract and title of all potential publications were then screened for clinical trials and to remove non-English articles, non-human or animal trials, and other non-dental or non-relevant studies. A total of 1,657 citations were initially identified, reviewed, and screened, eventually resulting in inclusion of 25 clinical trials in this systematic review. Nineteen studies evaluated ketamine effects in pediatric dental sedation using oral (non-invasive) administration, three involved subcutaneous or intramuscular injection, and three were completed intravenously. Evidence analysis of these trials revealed the majority (n = 22/25) provided strong, positive evidence for the use of ketamine (alone or in combination) to reduce dental anxiety and behavioral non-compliance with the remainder suggesting equivocal results. Additional endpoints evaluated in some studies involved dosage, as well as time to achieve sedation effect. The use of ketamine (alone or in combination) can provide safe, effective, and timely sedation in pediatric patients regardless of the route of

[Sedation in the terminal phase of life].

Science.gov (United States)

Verhagen, E H; Eliel, M R; de Graeff, A; Teunissen, S C

1999-12-25

In 2 patients, a woman aged 38 years and a man aged 48 years, in the terminal phase of life due to metastasized+ malignancy, palliative care failed. They suffered seriously from pain, delirium, restlessness, nausea, and fear. Deep sedation was given to induce almost continuous sleep without the intention of causing death. After one and five quiet days respectively the patients died. Deep sedation is an option when palliative care fails to diminish serious suffering. Midazolam, given by continuous subcutaneous infusion is the drug of choice.

Understanding and predicting soot generation in turbulent non-premixed jet flames.

Energy Technology Data Exchange (ETDEWEB)

Wang, Hai (University of Southern California, Los Angeles, CA); Kook, Sanghoon; Doom, Jeffrey; Oefelein, Joseph Charles; Zhang, Jiayao; Shaddix, Christopher R.; Schefer, Robert W.; Pickett, Lyle M.

2010-10-01

This report documents the results of a project funded by DoD's Strategic Environmental Research and Development Program (SERDP) on the science behind development of predictive models for soot emission from gas turbine engines. Measurements of soot formation were performed in laminar flat premixed flames and turbulent non-premixed jet flames at 1 atm pressure and in turbulent liquid spray flames under representative conditions for takeoff in a gas turbine engine. The laminar flames and open jet flames used both ethylene and a prevaporized JP-8 surrogate fuel composed of n-dodecane and m-xylene. The pressurized turbulent jet flame measurements used the JP-8 surrogate fuel and compared its combustion and sooting characteristics to a world-average JP-8 fuel sample. The pressurized jet flame measurements demonstrated that the surrogate was representative of JP-8, with a somewhat higher tendency to soot formation. The premixed flame measurements revealed that flame temperature has a strong impact on the rate of soot nucleation and particle coagulation, but little sensitivity in the overall trends was found with different fuels. An extensive array of non-intrusive optical and laser-based measurements was performed in turbulent non-premixed jet flames established on specially designed piloted burners. Soot concentration data was collected throughout the flames, together with instantaneous images showing the relationship between soot and the OH radical and soot and PAH. A detailed chemical kinetic mechanism for ethylene combustion, including fuel-rich chemistry and benzene formation steps, was compiled, validated, and reduced. The reduced ethylene mechanism was incorporated into a high-fidelity LES code, together with a moment-based soot model and models for thermal radiation, to evaluate the ability of the chemistry and soot models to predict soot formation in the jet diffusion flame. The LES results highlight the importance of including an optically-thick radiation

Apneic oxygenation for elimination of respiratory motion artefact in an intubated patient undergoing helical chest computed tomography angiography.

Directory of Open Access Journals (Sweden)

Ioannis Pneumatikos

2008-10-01

Full Text Available Respiratory motion artifact in intubated and mechanically ventilated patients often reduces the quality of helical computed tomography pulmonary angiography (CTPA. Apneic oxygenation is a well established intra-operative technique that allows adequate oxygenation for short periods (up to 10 min in sedated and paralyzed patients. We describe the use of the apneic oxygenation for elimination of respiratory motion artefact in an intubated patient undergoing helical chest computed tomography angiography.

Psychometric analysis of subjective sedation scales used for critically ill paediatric patients.

Science.gov (United States)

Ge, Xiaohua; Zhang, Tingting; Zhou, Lingling

2018-01-01

This study evaluated the psychometric properties of subjective sedation scales using one psychometric scoring system to identify the appropriate scale that is most suitable for clinical care practice. A number of published sedation assessment scales for paediatric patients are currently used to attempt to achieve a moderate depth of sedation to avoid the undesirable effects caused by over- or undersedation. However, there has been no systematic review of these scales. We searched the Cochrane Library, PubMed, EMBASE, the Cumulative Index to Nursing and Allied Health Literature, etc., to obtain relevant articles. The quality of the selected studies was evaluated according to the Consensus-based Standards for the Selection of Health Measurement Instruments checklist. Articles that had been published or were in press and discussed the psychometric properties of sedation scales were included. The population comprised critically ill infants and non-verbal children ranging in age from 0 to 18 years who underwent sedation in an intensive care unit. Data were independently extracted by two investigators using a standard data extraction checklist: 43 articles were included in this review, and 13 sedation scales were examined. The quality of the psychometric evidence for the Comfort Scale and Comfort Behaviour Scale was 'very good', with the Comfort Scale having a higher quality (total weighted scores, Comfort Scale = 17·3 and Comfort Behaviour Scale = 15·5). We suggest that the scales be systematically and comprehensively tested in terms of development method, reliability, validation, feasibility and correlation with clinical outcome. The Comfort Scale and Comfort Behaviour Scale are useful tools for measuring sedation in paediatric patients. Nursing staff should choose one subjective sedation scale that is suitable for assessing paediatric patients' depth of sedation. We recommend the Comfort Scale and Comfort Behaviour Scale as optimal choices if the clinical

Methane combustion in catalytic premixed burners

International Nuclear Information System (INIS)

Cerri, I.; Saracco, G.; Specchia, V.

1999-01-01

Catalytic premixed burners for domestic boiler applications were developed with the aim of achieving a power modularity from 10 to 100% and pollutant emissions limited to NO x 2 , where the combustion took place entirely inside the burner heating it to incandescence and allowing a decrease in the flame temperature and NO x emissions. Such results were confirmed through further tests carried out in a commercial industrial-scale boiler equipped with the conical panels. All the results, by varying the excess air and the heat power employed, are presented and discussed [it

Continuous sedation until death as physician-assisted suicide/euthanasia: a conceptual analysis.

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Lipuma, Samuel H

2013-04-01

A distinction is commonly drawn between continuous sedation until death and physician-assisted suicide/euthanasia. Only the latter is found to involve killing, whereas the former eludes such characterization. I argue that continuous sedation until death is equivalent to physician-assisted suicide/euthanasia in that both involve killing. This is established by first defining and clarifying palliative sedation therapies in general and continuous sedation until death in particular. A case study analysis and a look at current practices are provided. This is followed by a defense of arguments in favor of definitions of death centering on higher brain (neocortical) functioning rather than on whole brain or cardiopulmonary functioning. It is then shown that continuous sedation until death simulates higher brain definitions of death by eliminating consciousness. Appeals to reversibility and double effect fail to establish any distinguishing characteristics between the simulation of death that occurs in continuous sedation until death and the death that occurs as a result of physician-assisted suicide/euthanasia. Concluding remarks clarify the moral ramifications of these findings.

Wake-up times following sedation with sevoflurane versus propofol after cardiac surgery.

Science.gov (United States)

Hellström, Jan; Öwall, Anders; Sackey, Peter V

2012-10-01

Intravenous sedation in the intensive care unit (ICU) may contribute to altered consciousness and prolonged mechanical ventilation. We tested the hypothesis that replacing intravenous propofol with inhaled sevoflurane for sedation after cardiac surgery would lead to shorter wake-up times, quicker patient cooperation, and less delusional memories. Following coronary artery bypass surgery with cardiopulmonary bypass, 100 patients were randomized to sedation with sevoflurane via the anesthetic conserving device or propofol. Study drugs were administered for a minimum of 2 hours until criteria for extubation were met. Primary endpoints were time from drug stop to extubation and to adequate verbal response. Secondary endpoints were adverse recovery events, memories reported in the ICU Memory Tool test, and ICU/hospital stay. Median time from drug stop to extubation (interquartile range/total range) was shorter after sevoflurane compared to propofol sedation; 10 (10/100) minutes versus 25 (21/240) minutes (p sedation after cardiac surgery leads to shorter wake-up times and quicker cooperation compared to propofol. No differences were seen in ICU-stay, adverse memories or recovery events in our short-term sedation.

Experimental study of a premixed oscillating flame stabilized inside the tube

Energy Technology Data Exchange (ETDEWEB)

Choi, B.I.; Shin, H.D. [Department of Mechanical Engineering, Korea Advanced Institute of Science and Technology, Taejon (Korea, Republic of)

1998-04-01

An experimental study of premixed oscillating flame stabilized inside the tube has been conducted in order to examine the kinematic behavior of premixed flame under the flow oscillation and flame/flow interaction. Flow oscillation is accomplished by an acoustic excitation. Oscillating nature of flow has been studied with and without the flame using velocity and pressure measurements by a LDV and microphone, respectively Kinematic behavior of the oscillating flame is examined using triggered ICCD camera system. Velocity oscillation and flame oscillation is the same frequency as that produced by the acoustic excitation and flame shape has a similarity at various phase of oscillation. Upstream velocity field near the flame zone is greatly influenced by the flame oscillation. This is the typical example of flame/flow interaction. (author). 9 refs., 7 figs.

Optimization of gas mixing system of premixed burner based on CFD analysis

International Nuclear Information System (INIS)

Zhang, Tian-Hu; Liu, Feng-Guo; You, Xue-Yi

2014-01-01

Highlights: • New multi-ejectors gas mixing system for premixed combustion burner is provided. • Two measures are proposed to improve the flow uniformity at the outlet of GMS. • Small improvement of uniformity induces significant decrease of pollutant emission. • Uniformity of velocity and fuel–gas mixing of ejector increases 234.2% and 2.9%. • Uniformity of flow rate and fuel–gas mixing of ejectors increases 1.9% and 2.2%. - Abstract: The optimization of gas mixing system (GMS) of premixed burner is presented by Computational Fluid Dynamics (CFD) and the uniformity at the outlet of GMS is proved experimentally to have strong influence on pollutant emission. To improve the uniformity at the outlet of GMS, the eleven distribution orifice plates and a diversion plate are introduced. The quantified analysis shows that the uniformity at the outlet of GMS is improved significantly. With applying the distribution orifice plates, the uniformity of velocity and fuel–gas mixing of single ejector is increased by 234.2% and 2.9%, respectively. With applying the diversion plate, the uniformity of flow rate and fuel–gas mixing of different ejectors is increased by 1.9% and 2.2%, respectively. The optimal measures and geometrical parameters provide an applicable guidance for the design of commercial premixed burner

Cost analysis of premixed multichamber bags versus compounded parenteral nutrition: breakeven point.

Science.gov (United States)

Bozat, Erkut; Korubuk, Gamze; Onar, Pelin; Abbasoglu, Osman

2014-02-01

Industrially premixed multichamber bags or hospital-manufactured compounded products can be used for parenteral nutrition. The aim of this study was to compare the cost of these 2 approaches. Costs of compounded parenteral nutrition bags in an university hospital were calculated. A total of 600 bags that were administered during 34 days between December 10, 2009 and February 17, 2010 were included in the analysis. For quality control, specific gravity evaluation of the filled bags was performed. It was calculated that the variable cost of a hospital compounded bag was $26.15. If we take the annual fixed costs into consideration, the production cost reaches $36.09 for each unit. It was estimated that the cost for the corresponding multichamber bag was $37.79. Taking the fixed and the variable costs into account, the breakeven point of the hospital compounded and the premixed multichamber bags was seen at 5,404 units per year. In specific gravity evaluation, it was observed that the mean and interval values were inside the upper and lower control margins. In this analysis, usage of hospital-compounded parenteral nutrition bags showed a cost advantage in hospitals that treat more than 15 patients per day. In small volume hospitals, premixed multichamber bags may be more beneficial.

Development of Criteria for Flameholding Tendencies within Premixer Passages for High Hydrogen Content Fuels

Energy Technology Data Exchange (ETDEWEB)

Lewis, Elliot Sullivan- [Univ. of California, Irvine, CA (United States); McDonell, Vincent G. [Univ. of California, Irvine, CA (United States)

2014-12-01

Due to increasingly stringent air quality requirements stationary power gas turbines have moved to lean-premixed operation, which reduces pollutant emissions but can result in flashback. Flashback can cause serious damage to the premixer hardware. Curtailing flashback can be difficult with hydrocarbon fuels and becomes even more challenging when hydrogen is used as the fuel. The two main approaches for coping with flashback are either to design a combustor that is resistant to flashback, or to design a premixer that will not anchor a flame if flashback occurs. Even with a well-designed combustor flashback can occur under certain circumstances, thus it is necessary to determine how to avoid flameholding within the premixer passageways of a gas turbine. To this end, an experiment was designed that would determine the flameholding propensities at elevated pressures and temperatures of three different classes of geometric features commonly found in gas turbine premixers, with both natural gas and hydrogen fuel. Experiments to find the equivalence ratio at blow off were conducted within an optically accessible test apparatus with four flameholders: 0.25 and 0.50 inch diameter cylinders, a reverse facing step with a height of 0.25 inches, and a symmetric airfoil with a thickness of 0.25 inches and a chord length of one inch. Tests were carried out at temperatures between 300 K and 750 K, at pressures up to 9 atmospheres. Typical bulk velocities were between 40 and 100 m/s. The effect of airfoil’s angle of rotation was also investigated. Blow off for hydrogen flames was found to occur at much lower adiabatic flame temperatures than natural gas flames. Additionally it was observed that at high pressures and high turbulence intensities, reactant velocity does not have a noticeable effect on the point of blow off due in large part to corresponding increases in turbulent flame speed. Finally a semi empirical correlation was developed that predicts flame extinction for both

Sedation of children for MR or CT imaging examination using chloral hydrate

International Nuclear Information System (INIS)

Song, Jong Gi; Kim, Woo Sun; Kim, In One; Yeon, Kyung Mo; Han, Man Chung

1994-01-01

Pediatric sedation is an important factor for obtaining the images of good quality. We performed this study to analyze the efficacy of our sedation protocol using chloral hydrate. We collected prospectively 151 sedation records of children(1 day-15 years old), who were sedated with chloral hydrate for MR(n=112) or CT(n=39) studies. We initially administered 50 mg/Kg orally(n=94) or rectally(n=57) 30 minutes before the scheduled examinations, and then administered additional dose (second dose: 25-35 mg/Kg, third dose: 10-15 mg/Kg) to patients whom initial dose failed to sedate. Satisfactory sedation was achieved by initial administration in 109 patients(72%) without significant difference between oral(per oral; P. O.) and rectal(per rectal: P.R.) administration. Second dose was required in 28% and third dose in 5%. MR and CT examinations required second dose in 36(32%) and 6 patients(15%), respectively. P.O. -patients vomited in 5%. P.R. -patients defecated in 22% after initial administration. There were no other serious complications. Time interval from the drug administration to the start of examinations was 33 minutes in initial-dose-group and 64 minutes in additional-dose-group. Two patients could not complete MR examination due to early arousal. Prolonged sedation, requiring more than 30 minutes for alertness after MR and CT examinations, was encountered in twenty(18%) and two patients(5%) respectively. Our protocol using chloral hydrate(P.O. or P.R.) is thought to be an effective and safe method for pediatric sedation for MR or CT imaging

Investigation of Scalar Filtered Density Function in Turbulent Partially Premixed Flames

National Research Council Canada - National Science Library

Tong, Chenning

2006-01-01

... using measurement data obtained in turbulent partially premixed methane/air (Sandia) flames. For SGS scalar variance small compared to its mean, the FMDF is not far from Gaussian and the SGS scalar is well mixed...

Investigating the effects of nitrous oxide sedation on frontal-parietal interactions.

Science.gov (United States)

Ryu, Ji-Ho; Kim, Pil-Jong; Kim, Hong-Gee; Koo, Yong-Seo; Shin, Teo Jeon

2017-06-09

Although functional connectivity has received considerable attention in the study of consciousness, few studies have investigated functional connectivity limited to the sedated state where consciousness is maintained but impaired. The aim of the present study was to investigate changes in functional connectivity of the parietal-frontal network resulting from nitrous oxide-induced sedation, and to determine the neural correlates of cognitive impairment during consciousness transition states. Electroencephalography was acquired from healthy adult patients who underwent nitrous oxide inhalation to induce cognitive impairment, and was analyzed using Granger causality (GC). Periods of awake, sedation and recovery for GC between frontal and parietal areas in the delta, theta, alpha, beta, gamma and total frequency bands were obtained. The Friedman test with post-hoc analysis was conducted for GC values of each period for comparison. As a sedated state was induced by nitrous oxide inhalation, power in the low frequency band showed increased activity in frontal regions that was reversed with discontinuation of nitrous oxide. Feedback and feedforward connections analyzed in spectral GC were changed differently in accordance with EEG frequency bands in the sedated state by nitrous oxide administration. Calculated spectral GC of the theta, alpha, and beta frequency regions in the parietal-to-frontal direction was significantly decreased in the sedated state while spectral GC in the reverse direction did not show significant change. Frontal-parietal functional connectivity is significantly affected by nitrous oxide inhalation. Significantly decreased parietal-to-frontal interaction may induce a sedated state. Copyright © 2017 Elsevier B.V. All rights reserved.

Pharmacological therapy for analgesia and sedation in the newborn.

Science.gov (United States)

Anand, K J S; Hall, R W

2006-11-01

Rapid advances have been made in the use of pharmacological analgesia and sedation for newborns requiring neonatal intensive care. Practical considerations for the use of systemic analgesics (opioids, non-steroidal anti-inflammatory agents, other drugs), local and topical anaesthetics, and sedative or anaesthetic agents (benzodiazepines, barbiturates, other drugs) are summarised using an evidence-based medicine approach, while avoiding mention of the underlying basic physiology or pharmacology. These developments have inspired more humane approaches to neonatal intensive care. Despite these advances, little is known about the clinical effectiveness, immediate toxicity, effects on special patient populations, or long-term effects after neonatal exposure to analgesics or sedatives. The desired or adverse effects of drug combinations, interactions with non-pharmacological interventions or use for specific conditions also remain unknown. Despite the huge gaps in our knowledge, preliminary evidence for the use of neonatal analgesia and sedation is available, but must be combined with a clear definition of clinical goals, continuous physiological monitoring, evaluation of side effects or tolerance, and consideration of long-term clinical outcomes.

Flemish Palliative-Care Nurses’ Attitudes to Palliative Sedation: Results of a Quantitative Study

OpenAIRE

Gielen, Joris; Van den Branden, Stef; van Iersel, Trudie; Broeckaert, Bert

2012-01-01

Palliative sedation is an option of last resort to control refractory suffering. In order to better understand palliative-care nurses’ attitudes to palliative sedation, an anonymous questionnaire was sent to all nurses (589) employed in palliative care in Flanders (Belgium). In all, 70.5% of the nurses (n=415) responded. A large majority did not agree that euthanasia is preferable to palliative sedation, were against non-voluntary euthanasia in the case of a deeply and continuously sedated pa...

The experiences of relatives with the practice of palliative sedation: a systematic review.

Science.gov (United States)

Bruinsma, Sophie M; Rietjens, Judith A C; Seymour, Jane E; Anquinet, Livia; van der Heide, Agnes

2012-09-01

Guidelines about palliative sedation typically include recommendations to protect the well-being of relatives. The aim of this study was to systematically review evidence on the experiences of relatives with the practice of palliative sedation. PubMed, Embase, Web of Science, PsycINFO, and CINAHL were searched for empirical studies on relatives' experiences with palliative sedation. We investigated relatives' involvement in the decision-making and sedation processes, whether they received adequate information and support, and relatives' emotions. Of the 564 studies identified, 39 were included. The studies (30 quantitative, six qualitative, and three mixed methods) were conducted in 16 countries; three studies were based on relatives' reports, 26 on physicians' and nurses' proxy reports, seven on medical records, and three combined different sources. The 39 studies yielded a combined total of 8791 respondents or studied cases. Caregivers involved relatives in the decision making in 69%-100% of all cases (19 quantitative studies), and in 60%-100% of all cases, relatives were reported to have received adequate information (five quantitative studies). Only two quantitative studies reported on relatives' involvement in the provision of sedation. Despite the fact that the majority of relatives were reported to be comfortable with the use of palliative sedation (seven quantitative studies, four qualitative studies), several studies found that relatives were distressed by the use of sedation (five quantitative studies, five qualitative studies). No studies reported specifically about the support provided to the relatives. Relatives' experiences with palliative sedation are mainly studied from the perspective of proxies, mostly professional caregivers. The majority of relatives seems to be comfortable with the use of palliative sedation; however, they may experience substantial distress by the use of sedation. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published

Walking the line. Palliative sedation for existential distress: still a controversial issue?

Science.gov (United States)

Schur, Sophie; Radbruch, Lukas; Masel, Eva K; Weixler, Dietmar; Watzke, Herbert H

2015-12-01

Adequate symptom relief is a central aspect of medical care of all patients especially in those with an incurable disease. However, as an illness progresses and the end of life approaches, physical or psychoexistential symptoms may remain uncontrollable requiring palliative sedation. Although palliative sedation has become an increasingly implemented practice in the care of terminally ill patients, sedation in the management of refractory psychological symptoms and existential distress is still a controversial issue and much debated. This case report presents a patient who received palliative sedation for the treatment of existential distress and discusses considerations that may arise from such a therapeutic approach.

Quantification of trace metals in infant formula premixes using laser-induced breakdown spectroscopy

Science.gov (United States)

Cama-Moncunill, Raquel; Casado-Gavalda, Maria P.; Cama-Moncunill, Xavier; Markiewicz-Keszycka, Maria; Dixit, Yash; Cullen, Patrick J.; Sullivan, Carl

2017-09-01

Infant formula is a human milk substitute generally based upon fortified cow milk components. In order to mimic the composition of breast milk, trace elements such as copper, iron and zinc are usually added in a single operation using a premix. The correct addition of premixes must be verified to ensure that the target levels in infant formulae are achieved. In this study, a laser-induced breakdown spectroscopy (LIBS) system was assessed as a fast validation tool for trace element premixes. LIBS is a promising emission spectroscopic technique for elemental analysis, which offers real-time analyses, little to no sample preparation and ease of use. LIBS was employed for copper and iron determinations of premix samples ranging approximately from 0 to 120 mg/kg Cu/1640 mg/kg Fe. LIBS spectra are affected by several parameters, hindering subsequent quantitative analyses. This work aimed at testing three matrix-matched calibration approaches (simple-linear regression, multi-linear regression and partial least squares regression (PLS)) as means for precision and accuracy enhancement of LIBS quantitative analysis. All calibration models were first developed using a training set and then validated with an independent test set. PLS yielded the best results. For instance, the PLS model for copper provided a coefficient of determination (R2) of 0.995 and a root mean square error of prediction (RMSEP) of 14 mg/kg. Furthermore, LIBS was employed to penetrate through the samples by repetitively measuring the same spot. Consequently, LIBS spectra can be obtained as a function of sample layers. This information was used to explore whether measuring deeper into the sample could reduce possible surface-contaminant effects and provide better quantifications.

Nitric Oxide and Oxygen Air-Contamination Effects on Extinction Limits of Non-Premixed Hydrocarbon-Air Flames for a HIFiRE Scramjet

Science.gov (United States)

Pellett, Gerald L.; Dawson, Lucy C.; Vaden, Sarah N.; Wilson, Lloyd G.

2009-01-01

Unique nitric oxide (NO) and oxygen air-contamination effects on the extinction Flame Strength (FS) of non-premixed hydrocarbon (HC) vs. air flames are characterized for 7 gaseous HCs, using a new idealized 9.3 mm straight-tube Opposed Jet Burner (OJB) at 1 atm. FS represents a laminar strain-induced extinction limit based on cross-section-average air jet velocity, Uair, that sustains combustion of a counter jet of gaseous fuel just before extinction. Besides ethane, propane, butane, and propylene, the HCs include ethylene, methane, and a 64 mole-% ethylene / 36 % methane mixture, the writer s previously recommended gaseous surrogate fuel for HIFiRE scramjet tests. The HC vs. clean air part of the work is an extension of a May 2008 JANNAF paper that characterized surrogates for the HIFiRE project that should mimic the flameholding of reformed (thermally- or catalytically-cracked) endothermic JP-like fuels. The new FS data for 7 HCs vs. clean air are thus consolidated with the previously validated data, normalized to absolute (local) axial-input strain rates, and co-plotted on a dual kinetically dominated reactivity scale. Excellent agreement with the prior data is obtained for all 7 fuels. Detailed comparisons are also made with recently published (Univ. Va) numerical results for ethylene extinction. A 2009-revised ethylene kinetic model (Univ. Southern Cal) led to predicted limits within approx. 5 % (compared to 45 %, earlier) of this writer s 2008 (and present) ethylene FSs, and also with recent independent data (Univ. Va) obtained on a new OJB system. These +/- 5 % agreements, and a hoped-for "near-identically-performing" reduced kinetics model, would greatly enhance the capability for accurate numerical simulations of surrogate HC flameholding in scramjets. The measured air-contamination effects on normalized FS extinction limits are projected to assess ongoing Arc-Heater-induced "facility test effects" of NO production (e.g., 3 mole-%) and resultant oxygen

Dreaming in sedation during spinal anesthesia: a comparison of propofol and midazolam infusion.

Science.gov (United States)

Kim, Duk-Kyung; Joo, Young; Sung, Tae-Yun; Kim, Sung-Yun; Shin, Hwa-Yong

2011-05-01

Although sedation is often performed during spinal anesthesia, the details of intraoperative dreaming have not been reported. We designed this prospective study to compare 2 different IV sedation protocols (propofol and midazolam infusion) with respect to dreaming during sedation. Two hundred twenty adult patients were randomly assigned to 2 groups and received IV infusion of propofol or midazolam for deep sedation during spinal anesthesia. Patients were interviewed on emergence and 30 minutes later to determine the incidence, content, and nature of their dreams. Postoperatively, patient satisfaction with the sedation was also evaluated. Two hundred fifteen patients (108 and 107 in the propofol and midazolam groups, respectively) were included in the final analysis. The proportion of dreamers was 39.8% (43/108) in the propofol group and 12.1% (13/107) in the midazolam group (odds ratio=4.78; 95% confidence interval: 2.38 to 9.60). Dreams of the patients receiving propofol were more memorable and visually vivid than were those of the patients receiving midazolam infusion. The majority of dreams (36 of 56 dreamers, 64.3%) were simple, pleasant ruminations about everyday life. A similarly high level of satisfaction with the sedation was observed in both groups. In cases of spinal anesthesia with deep sedation, dreaming was almost 5 times more common in patients receiving propofol infusion than in those receiving midazolam, although this did not influence satisfaction with the sedation. Thus, one does not need to consider intraoperative dreaming when choosing propofol or midazolam as a sedative drug in patients undergoing spinal anesthesia. © 2011 International Anesthesia Research Society

Pressure ulcers in critically ill patients - Preventable by non-sedation? A substudy of the NONSEDA-trial.

Science.gov (United States)

Nedergaard, Helene K; Haberlandt, Trine; Toft, Palle; Jensen, Hanne Irene

2018-02-01

Pressure ulcers still pose a significant clinical challenge to critically ill patients. This study is a substudy of the multicenter NONSEDA-trial, where critically ill patients were randomised to sedation or non-sedation during mechanical ventilation. The objective of this substudy was to assess if non-sedation affected the occurrence of pressure ulcers. Retrospective assessment of data from a single NONSEDA-trial site. Mixed intensive care unit. The occurrence of pressure ulcers, described by grade and location. 205 patients were included. Patients with pressure ulcers in the two groups were comparable with regards to baseline data. There were 44 ulcers in 32 patients in the sedated group and 31 ulcers in 25 patients in the non-sedated group (p=0.08). 64% of the ulcers in sedated patients were located on sacrum and heels, whereas 68% of the ulcers in non-sedated patients were related to equipment (p=0.03). Non-sedation did not significantly reduce the number of pressure ulcers. Non-sedation significantly affected the location of ulcers: non-sedated patients mainly had ulcers related to equipment, whereas sedated patients mainly had ulcers on the sacrum and heels. Copyright © 2017 Elsevier Ltd. All rights reserved.

Propofol-Based Palliative Sedation to Treat Antipsychotic-Resistant Agitated Delirium.

Science.gov (United States)

Covarrubias-Gómez, Alfredo; López Collada-Estrada, Maria

Delirium is a common problem in terminally ill patients that is associated with significant distress and, hence, considered a palliative care emergency. The three subtypes of delirium are hyperactive, hypoactive, and mixed, depending on the level of psychomotor activity and arousal disturbance. When agitated delirium becomes refractory in the setting of imminent dying, the agitation may be so severe that palliative sedation (PS) is required. Palliative sedation involves the administration of sedative medications with the purpose of reducing level of consciousness for patients with refractory suffering in the setting of a terminal illness. Propofol is a sedative that has a short duration of action and a very rapid onset. These characteristics make it relatively easy to titrate. Reported doses range from 50 to 70 mg per hour. The authors present a case of antipsychotic-resistant agitated delirium treated with a propofol intravenous infusion.

The route of liquid precursor to ZnO nanoparticles in premixed combustion spray pyrolysis

Science.gov (United States)

Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

2018-04-01

Zinc oxide nanoparticles had been successfully synthesized by premixed combustion spray pyrolysis. Zinc acetate was dissolved in distilled water was selected as a liquid precursor. Zinc nitrate was also used for comparison the effect of precursor type on the generated particles morphology and the crystallinity. The premixed combustion reaction used liquefied petroleum gas (LPG) mainly consisting of butane and propane as a fuel and compressed air used as an oxidizer. The liquid precursor was atomized using a custom two fluid nozzle to generate droplets. Then, the droplets were sprayed by the flow of air as a carrier gas into the premixed combustion reactor. The zinc precursor was decomposed to zinc oxide due to the high temperature as a result of combustion reaction inside the reactor resulting in nanoparticles formation. The particle size decreased with the increase of the fuel flow rate. In addition, it can be found that at the same flow rate of fuel, the particle size of zinc oxide synthesized using zinc nitrate is larger than that of the use of zinc acetate as a precursor.

Inhalation Conscious Sedation with Nitrous Oxide and Oxygen as Alternative to General Anesthesia in Precooperative, Fearful, and Disabled Pediatric Dental Patients: A Large Survey on 688 Working Sessions

Science.gov (United States)

Galeotti, Angela; Garret Bernardin, Annelyse; D'Antò, Vincenzo; Viarani, Valeria; Cassabgi, Giorgio

2016-01-01

Aim. To evaluate the effectiveness and the tolerability of the nitrous oxide sedation for dental treatment on a large pediatric sample constituting precooperative, fearful, and disabled patients. Methods. 472 noncooperating patients (aged 4 to 17) were treated under conscious sedation. The following data were calculated: average age; gender distribution; success/failure; adverse effects; number of treatments; kind of dental procedure undertaken; number of dental procedures for each working session; number of working sessions for each patient; differences between males and females and between healthy and disabled patients in relation to success; success in relation to age; and level of cooperation using Venham score. Results. 688 conscious sedations were carried out. The success was 86.3%. Adverse effects occurred in 2.5%. 1317 dental procedures were performed. In relation to the success, there was a statistically significant difference between healthy and disabled patients. Sex and age were not significant factors for the success. Venham score was higher at the first contact with the dentist than during the treatment. Conclusions. Inhalation conscious sedation represented an effective and safe method to obtain cooperation, even in very young patients, and it could reduce the number of pediatric patients referred to hospitals for general anesthesia. PMID:27747238

Inhalation Conscious Sedation with Nitrous Oxide and Oxygen as Alternative to General Anesthesia in Precooperative, Fearful, and Disabled Pediatric Dental Patients: A Large Survey on 688 Working Sessions

Directory of Open Access Journals (Sweden)

Angela Galeotti

2016-01-01

Full Text Available Aim. To evaluate the effectiveness and the tolerability of the nitrous oxide sedation for dental treatment on a large pediatric sample constituting precooperative, fearful, and disabled patients. Methods. 472 noncooperating patients (aged 4 to 17 were treated under conscious sedation. The following data were calculated: average age; gender distribution; success/failure; adverse effects; number of treatments; kind of dental procedure undertaken; number of dental procedures for each working session; number of working sessions for each patient; differences between males and females and between healthy and disabled patients in relation to success; success in relation to age; and level of cooperation using Venham score. Results. 688 conscious sedations were carried out. The success was 86.3%. Adverse effects occurred in 2.5%. 1317 dental procedures were performed. In relation to the success, there was a statistically significant difference between healthy and disabled patients. Sex and age were not significant factors for the success. Venham score was higher at the first contact with the dentist than during the treatment. Conclusions. Inhalation conscious sedation represented an effective and safe method to obtain cooperation, even in very young patients, and it could reduce the number of pediatric patients referred to hospitals for general anesthesia.

Evaluation of partially premixed turbulent flame stability from mixture fraction statistics in a slot burner

KAUST Repository

Kruse, Stephan

2018-04-11

Partially premixed combustion is characterized by mixture fraction inhomogeneity upstream of the reaction zone and occurs in many applied combustion systems. The temporal and spatial fluctuations of the mixture fraction have tremendous impact on the combustion characteristics, emission formation, and flame stability. In this study, turbulent partially premixed flames are experimentally studied in a slot burner configuration. The local temperature and gas composition is determined by means of one-dimensional, simultaneous detection of Rayleigh and Raman scattering. The statistics of the mixture fraction are utilized to characterize the impact of the Reynolds number, the global equivalence ratio, the progress of mixing within the flame, as well as the mixing length on the mixing field. Furthermore, these effects are evaluated by means of a regime diagram for partially premixed flames. In this study, it is shown that the increase of the mixing length results in a significantly more stable flame. The impact of the Reynolds number on flame stability is found to be minor.

Evaluation of partially premixed turbulent flame stability from mixture fraction statistics in a slot burner

KAUST Repository

Kruse, Stephan; Mansour, Mohy S.; Elbaz, Ayman M.; Varea, Emilien; Grü nefeld, Gerd; Beeckmann, Joachim; Pitsch, Heinz

2018-01-01

Partially premixed combustion is characterized by mixture fraction inhomogeneity upstream of the reaction zone and occurs in many applied combustion systems. The temporal and spatial fluctuations of the mixture fraction have tremendous impact on the combustion characteristics, emission formation, and flame stability. In this study, turbulent partially premixed flames are experimentally studied in a slot burner configuration. The local temperature and gas composition is determined by means of one-dimensional, simultaneous detection of Rayleigh and Raman scattering. The statistics of the mixture fraction are utilized to characterize the impact of the Reynolds number, the global equivalence ratio, the progress of mixing within the flame, as well as the mixing length on the mixing field. Furthermore, these effects are evaluated by means of a regime diagram for partially premixed flames. In this study, it is shown that the increase of the mixing length results in a significantly more stable flame. The impact of the Reynolds number on flame stability is found to be minor.

Direct Numerical Simulations of Statistically Stationary Turbulent Premixed Flames

KAUST Repository

Im, Hong G.

2016-07-15

Direct numerical simulations (DNS) of turbulent combustion have evolved tremendously in the past decades, thanks to the rapid advances in high performance computing technology. Today’s DNS is capable of incorporating detailed reaction mechanisms and transport properties of hydrocarbon fuels, with physical parameter ranges approaching laboratory scale flames, thereby allowing direct comparison and cross-validation against laser diagnostic measurements. While these developments have led to significantly improved understanding of fundamental turbulent flame characteristics, there are increasing demands to explore combustion regimes at higher levels of turbulent Reynolds (Re) and Karlovitz (Ka) numbers, with a practical interest in new combustion engines driving towards higher efficiencies and lower emissions. The article attempts to provide a brief overview of the state-of-the-art DNS of turbulent premixed flames at high Re/Ka conditions, with an emphasis on homogeneous and isotropic turbulent flow configurations. Some important qualitative findings from numerical studies are summarized, new analytical approaches to investigate intensely turbulent premixed flame dynamics are discussed, and topics for future research are suggested. © 2016 Taylor & Francis.

Sedating children in South Africa

African Journals Online (AJOL)

bRed Cross War Memorial Children's Hospital, Cape Town, South Africa. cSedation and Pain ... As the authors indicate, there is increasing pressure from practitioners, funders and patients or parents for procedures to take place outside the ...

Comparison between chloral hydrate and propofol-ketamine as sedation regimens for pediatric auditory brainstem response testing.

Science.gov (United States)

Abulebda, Kamal; Patel, Vinit J; Ahmed, Sheikh S; Tori, Alvaro J; Lutfi, Riad; Abu-Sultaneh, Samer

2017-10-28

The use of diagnostic auditory brainstem response testing under sedation is currently the "gold standard" in infants and young children who are not developmentally capable of completing the test. The aim of the study is to compare a propofol-ketamine regimen to an oral chloral hydrate regimen for sedating children undergoing auditory brainstem response testing. Patients between 4 months and 6 years who required sedation for auditory brainstem response testing were included in this retrospective study. Drugs doses, adverse effects, sedation times, and the effectiveness of the sedative regimens were reviewed. 73 patients underwent oral chloral hydrate sedation, while 117 received propofol-ketamine sedation. 12% of the patients in the chloral hydrate group failed to achieve desired sedation level. The average procedure, recovery and total nursing times were significantly lower in the propofol-ketamine group. Propofol-ketamine group experienced higher incidence of transient hypoxemia. Both sedation regimens can be successfully used for sedating children undergoing auditory brainstem response testing. While deep sedation using propofol-ketamine regimen offers more efficiency than moderate sedation using chloral hydrate, it does carry a higher incidence of transient hypoxemia, which warrants the use of a highly skilled team trained in pediatric cardio-respiratory monitoring and airway management. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Use of sedation to relieve refractory symptoms in dying patients ...

African Journals Online (AJOL)

Indications. Agitated delirium was the most common reason (45%) for using sedation, followed by intractable vomiting due to inoperable malignant intestinal obstruction in 25% of patients. Three patients with persistent convulsions or myoclonic jerking and 2 patients with severe refractory dyspnoea required some sedation.

Quality of care in palliative sedation: audit and compliance monitoring of a clinical protocol.

Science.gov (United States)

Benitez-Rosario, Miguel Angel; Castillo-Padrós, Manuel; Garrido-Bernet, Belén; Ascanio-León, Belen

2012-10-01

The European Association for Palliative Care and the U.S. National Hospice and Palliative Care Organization have published statements that recommend an audit of palliative sedation practices. The aim was to assess the feasibility of a quality care project in palliative sedation. We carried out an audit of adherence to a guideline regarding palliative sedation, undertaken as a yearly assessment during two years, of a sample of patient charts. With an audit tool, the charts were evaluated as to the presence of the ethical sedation checklist, information that justified palliative sedation, patient and/or family agreement, and the appropriateness of treatment in concordance with the clinical protocol. An educational program and result feedback meetings were used as the implementation strategy. Roughly 25% of the medical charts of patients who died in the palliative care unit were evaluated, 94 in 2007 and 110 in 2008. In 2007 and 2008, 63% and 57% of the patients, respectively, whose median age was 65 years, were sedated, with a median length of two days. The main reason for sedation was agitation concomitant with respiratory failure in roughly 60% and 75% of the cases in 2007 and 2008, respectively. Agreement of the patient/family about sedation was collected from 100% of the cases. The concordance of procedures with the sedation guideline was 100% in both years. Our quality-of-care strategy was shown to obtain a higher level of compliance with the palliative sedation guideline for at least two years. Copyright © 2012 U.S. Cancer Pain Relief Committee. Published by Elsevier Inc. All rights reserved.

Increased precuneus connectivity during propofol sedation.

Science.gov (United States)

Liu, Xiaolin; Li, Shi-Jiang; Hudetz, Anthony G

2014-02-21

Using functional magnetic resonance imaging in human participants, we show that sedation by propofol to the point of lost overt responsiveness during the performance of an auditory verbal memory task unexpectedly increases functional connectivity of the precuneus with cortical regions, particularly the dorsal prefrontal and visual cortices. After recovery of consciousness, functional connectivity returns to a pattern similar to that observed during the wakeful baseline. In the context of a recent proposal that highlights the uncoupling of consciousness, connectedness, and responsiveness in general anesthesia, the increased precuneus functional connectivity under propofol sedation may reflect disconnected endogenous mentation or dreaming that continues at a reduced level of metabolic activity. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Dreaming and recall during sedation for colonoscopy.

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Stait, M L; Leslie, K; Bailey, R

2008-09-01

Dreaming is reported by one in five patients who are interviewed on emergence from general anaesthesia, but the incidence, predictors and consequences of dreaming during procedural sedation are not known. In this prospective observational study, 200 patients presenting for elective colonoscopy under intravenous sedation were interviewed on emergence to determine the incidences of dreaming and recall. Sedation technique was left to the discretion of the anaesthetist. The incidence of dreaming was 25.5%. Patients reporting dreaming were younger than those who did not report dreaming. Doses of midazolam and fentanyl were similar between dreamers and non-dreamers, however propofol doses were higher in patients who reported dreams than those who did not. Patients reported short, simple dreams about everyday life--no dream suggested near-miss recall of the procedure. Frank recall of the procedure was reported by 4% of the patients, which was consistent with propofol doses commensurate with light general anaesthesia. The only significant predictor of recall was lower propofol dose. Satisfaction with care was generally high, however dreamers were more satisfied with their care than non-dreamers.

Immunizations under sedation at a paediatric hospital in Melbourne, Australia from 2012-2016.

Science.gov (United States)

Cheng, Daryl R; Elia, Sonja; Perrett, Kirsten P

2018-05-09

Sedation for immunizations is of particular importance in a subset of paediatric patients with anxiety disorders, needle phobia, developmental or behavioural disorders. The Royal Children's Hospital (RCH) Melbourne offers a unique immunization under sedation service for these patients. We aimed to evaluate the number and types of patients using inpatient sedation for immunizations, distraction and sedation techniques used, and outcomes of these procedures. A medical record review was conducted on all patients who had immunization under sedation between January 2012 to December 2016 in the RCH Day Medical Unit (DMU). A total of 139 children and adolescents had 213 vaccination encounters. More than half of the vaccination encounters involved multiple vaccines. A total of 400 vaccines were administered. One third of patients (32.3%) had multiple DMU admissions for vaccinations. The median age of patients was 13 years. There were only 10 (4.7%) failed attempts at vaccination; all due to patient non-compliance with prescribed sedation. The majority of patients (58.9%) had a diagnosis of needle phobia. Sedation was most commonly adequately achieved with inhaled nitrous oxide (54.7% sole agent). Midazolam was often used as an adjunct therapy (42.8%). Local anaesthetic cream or play therapy, were used in only 5.9% and 3.9% of patients respectively, although this may reflect poor documentation rather than actual practice. For a subset of paediatric patients for which standard immunization procedures have failed, distraction techniques and conscious sedation enable immunizations to be given safely and effectively. Future research will develop protocols to streamline immunization procedures under sedation. Copyright © 2018 Elsevier Ltd. All rights reserved.

An Evaluation of Intranasal Sufentanil and Dexmedetomidine for Pediatric Dental Sedation

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James M. Hitt

2014-03-01

Full Text Available Conscious or moderate sedation is routinely used to facilitate the dental care of the pre- or un-cooperative child. Dexmedetomidine (DEX has little respiratory depressant effect, possibly making it a safer option when used as an adjunct to either opioids or benzodiazepines. Unlike intranasal (IN midazolam, IN application of DEX and sufentanil (SUF does not appear to cause much discomfort. Further, although DEX lacks respiratory depressive effects, it is an α2-agonist that can cause hypotension and bradycardia when given in high doses or during prolonged periods of administration. The aim of this feasibility study was to prospectively assess IN DEX/SUF as a potential sedation regimen for pediatric dental procedures. After IRB approval and informed consent, children (aged 3–7 years; n = 20 from our dental clinic were recruited. All patients received 2 μg/kg (max 40 μg of IN DEX 45 min before the procedure, followed 30 min later by 1 μg/kg (max 20 μg of IN SUF. An independent observer rated the effects of sedation using the Ohio State University Behavior Rating Scale (OSUBRS and University of Michigan Sedation Scale (UMSS. The dentist and the parent also assessed the efficacy of sedation. Dental procedures were well tolerated and none were aborted. The mean OSUBRS procedure score was 2.1, the UMSS procedure score was 1.6, and all scores returned to baseline after the procedure. The average dentist rated quality of sedation was 7.6 across the 20 subjects. After discharge, parents reported one child with prolonged drowsiness and one child who vomited at home. The use of IN DEX supplemented with IN SUF provided both an effective and tolerable form of moderate sedation. Although onset and recovery are slower than with oral (PO midazolam and transmucosal fentanyl, the quality of the sedation may be better with less risk of respiratory depression. Results from this preliminary study showed no major complications from IN delivery of these agents.

Day-to-day care in palliative sedation: survey of nurses' experiences with decision-making and performance.

Science.gov (United States)

Arevalo, Jimmy J; Rietjens, Judith A; Swart, Siebe J; Perez, Roberto S G M; van der Heide, Agnes

2013-05-01

Continuous palliative sedation has been the focus of extensive international debates in the field of end-of-life decision making. Although nurses may be important participants in the performance of continuous palliative sedation, research has focused primarily on the role and experience of physicians. Nurses' experiences differ from that of physicians; they more often describe that continuous palliative sedation is used with the intention of hastening death and to have experienced serious emotional burden. Therefore, it is important to understand the experience of nurses in continuous palliative sedation. To describe nurses' experiences with the decision-making and performance of continuous palliative sedation in terminally ill patients. Cross-sectional study. In 2008, a structured questionnaire was sent to 576 nurses in six professional home care organizations, ten units for palliative care in nursing homes and in-patient hospices and seven hospitals in the western region of the Netherlands. Respondents provided information about the last patient receiving continuous palliative sedation whom they had cared for. Two-hundred seventy-seven questionnaires were returned and 199 (71.84%) reported a case of continuous palliative sedation. Nurses felt involved in the decision to use sedation in 84% of cases, albeit to a lesser extent in home care (68.75%, p=0.002). They agreed with the performance of continuous palliative sedation in 95.97% of cases and they proposed the use of continuous palliative sedation in 16.16%. Nurses were present at the start of sedation in 81.40% of cases and reported physicians to be present in 45.22%. In 72.77%, arrangements had been made among caregivers about the coordination of health care regarding the sedation. Nurses seem to play an important role in the use of continuous sedation. This role is mainly supportive toward physicians and patients during the decision-making process, but shifts to an active performance of sedation

Palliative sedation in advanced cancer patients hospitalized in a specialized palliative care unit.

Science.gov (United States)

Parra Palacio, Santiago; Giraldo Hoyos, Clara Elisa; Arias Rodríguez, Camilo; Mejía Arrieta, Daniel; Vargas Gómez, John Jairo; Krikorian, Alicia

2018-03-29

To describe the practice of palliative sedation (PS) in patients with advanced cancer in a specialized palliative care (PC) unit in Colombia. Descriptive prospective study including all adults with cancer hospitalized under PS in a cancer institute between January and July 2015 in Colombia. Variables examined were diagnosis, physical functioning, symptoms at the start of sedation, medications and dosages used, and type, level, and time of sedation. Descriptive and correlational statistics were obtained. Sixty-six patients were included, 70% of which were women. The patients had an average age of 61 years (range 24-87), and 74% had a Karnofsky Index (KI) of 50% or less. The most frequent diagnosis was breast cancer (22%), and 82% had metastatic cancer. The prevalence of palliative sedation was 2% and the most common symptoms indicating it were dyspnea (59%), delirium (45%), and pain (32%). All patients received midazolam as a sedative. The average time between the interval start and culmination of sedation was 44 h. There was a significant and inverse relationship between functionality and time under sedation. Palliative sedation is a valid therapeutic option for refractory symptoms causing suffering. The results correspond to international reports and guidelines, which suggests that PS is tailored to the needs of the individual patient while maintaining a high scientific standard, even in a context where PC is under development. However, further development of strategies and clear indications towards the use of PS in Colombia are needed, given its still scarce use.

Effect of AC electric fields on the stabilization of premixed bunsen flames

KAUST Repository

Kim, Minkuk; Chung, Suk-Ho; Kim, Hwanho

2011-01-01

The stabilization characteristics of laminar premixed bunsen flames have been investigated experimentally for stoichiometric methane-air mixture by applying AC voltage to the nozzle with the single-electrode configuration. The detachment velocity

DNS of non-premixed combustion in a compressible mixing layer

NARCIS (Netherlands)

Bastiaans, R.J.M.; Somers, L.M.T.; Lange, de H.C.; Geurts, B.J.

2001-01-01

The non-premixed reaction of fuel with air in a mixing layer is studied using DNS. The situation is a model for the mixing-controlled combustion in a Diesel engine. We show that the combustion region can be comparably passive with respect to relatively large scale aerodynamic instabilities. However

Sedative Drug Use among King Saud University Medical Students: A Cross-Sectional Sampling Study

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Ahmed A. Al-Sayed

2014-01-01

Full Text Available Introduction. Medical students experience significant psychological stress and are therefore at higher risk of using sedatives. There are currently no studies describing the prevalence of sedative drug use among medical students in Saudi Arabia. The aim of this study was to evaluate the prevalence and factors associated with sedative drug use among medical students in Saudi Arabia. Materials and Methods. A cross-sectional convenience sampling study gathered data by anonymous questionnaire from students enrolled at the King Saud University College of Medicine in 2011. The questionnaires collected data regarding social and demographic variables, sleep patterns, and the use of stimulant and sedative drugs since enrollment. Sedatives were defined as any pharmaceutical preparations that induce sleep. Results and Discussion. Of the 729 students who returned questionnaires, 17.0% reported sedative drug use at some time since enrollment. Higher academic year, lower grade point average, regular exercise, fewer hours of sleep per day, poorer quality of sleep, and the presence of sleeping disorders were found to be significantly associated with sedative drug use. Conclusions. Further study is required to increase our understanding of sedative drug use patterns in this relatively high-risk group, as such understanding will help in the development of early intervention programs.

[Sedation with stimulative circadian rhythm in mechanically ventilation patients in intensive care unit].

Science.gov (United States)

Guo, Jian-ying; Deng, Qun; Guo, Xu-sheng; Liu, Shuang-qing; Zhang, Yu-hong; He, Zhong-jie; Yao, Yong-ming; Lin, Hong-yuan

2012-07-01

To sedate the mechanically ventilation patients in intensive care unit (ICU) with stimulative circadian rhythm, and evaluate whether the protocol has advantages in recovering natural circadian rhythm, duration of mechanical ventilation, and length of ICU stay after weaning of sedation. A prospective random control trial was conducted. One hundred and twenty ventilated patients in ICU were randomly assigned to four groups: circadian rhythm (CR), daily interruption (DI), continuous sedation (CS) or demand sedation (DS) group, each n = 30. Given more complications, DS group was deleted after recruiting 10 cases and 90 patients were admitted ultimately. Patients' age, gender, body weight, acute physiology and chronic health evaluation II (APACHE II) scores, sedatives dosages, daily arousal time, duration of mechanical ventilation, length of ICU stay, complications (ventilator-associated pneumonia, barotrauma with intrathoracic drain tube) and untoward reactions (accidental extubation, reintubation, tracheotomy, death) were recorded, the biochemical indicators were determined, as well as number of nurses on duty at 10:00 and 22:00. The patients' sex ratio, age, body weight, APACHEII scores, duration of mechanical ventilation, length of ICU stay showed no difference among CR, DI and CS groups. The total sedatives dosages (mg: 5466.7 ± 620.4) and average sedatives dosages [mg×h(-1) ×kg(-1): 2.19 ± 0.61] in CS group were significantly higher than those in CR group (4344.5 ± 816.0, 1.00 ± 0.51) and DI group (4154.3 ± 649.4, 1.23 ± 0.62, all P nurses on duty in the daytime (1.65, 1.41, 1.14, all P biochemistry index showed no difference in each group. It demonstrated that sedation with stimulative circadian rhythm be helpful to create circadian rhythm after weaning of sedation. While complications and untoward reactions did not increase, as well as duration of mechanical ventilation and length of ICU stay. Therefore, the clinical applicability of this sedative

Palliative sedation: the position statement of the Italian National Committee for Bioethics.

Science.gov (United States)

Orsi, Luciano; Gristina, Giuseppe R

2017-05-01

In January 2016 the Italian National Bioethics Committee (NBC) published a position statement entitled Deep and continuous palliative sedation in the imminence of death, related to the use of sedation and analgesia for relief from pain and psychological distress in dying patients. In this statement the Committee points out the clinical and ethical appropriateness of palliative sedation as a therapeutic procedure. As a result, today palliative sedation has to be considered useful, scientifically safe and reliable, and acknowledged as an integral part of good clinical practice. At the same time, the position statement, once and for all, makes clear that palliative sedation cannot and must not be equated with the practice of euthanasia. Thus, this document should be known by health professionals caring for dying patients not only in palliative as well as in intensive care settings, but it should be also considered as a milestone aimed to encourage and ease a widespread implementation of this procedure in all health care settings.

The role of midazolam-induced sedation in bone marrow aspiration/trephine biopsies.

Science.gov (United States)

Mainwaring, C J; Wong, C; Lush, R J; Smith, J G; Singer, C R

1996-12-01

This study was undertaken in 102 adult patients to evaluate the safety and efficacy of intravenous (i.v.) midazolam in the setting of bone marrow aspiration and trephine biopsy (BMAT). Combined local anaesthetic (LA) and sedation was used in 87% of patients and 13% received LA alone. Amnesia occurred in all sedated patients with only 9% experiencing a mild degree of post-procedure pain. This contrasted sharply with the non-sedated group, in whom 85% had intense pain during the biopsy followed by protracted local discomfort in approximately 54%. Drowsiness and some psychomotor impairment were the only notable sedation-related side-effects in approximately 20%. None required assisted ventilation. There was a resounding patient preference for BMAT with sedation. Considering the ease of use, safety and efficacy of i.v. midazolam, the availability of flumazenil as a reversal agent and the undoubted positive effects on quality of life, we would advocate using it in BMAT provided that there were no contraindications.

Visualization of the heat release zone of highly turbulent premixed jet flames

Science.gov (United States)

Lv, Liang; Tan, Jianguo; Zhu, Jiajian

2017-10-01

Visualization of the heat release zone (HRZ) of highly turbulent flames is significantly important to understand the interaction between turbulence and chemical reactions, which is the foundation to design and optimize engines. Simultaneous measurements of OH and CH2O using planar laser-induced fluorescence (PLIF) were performed to characterize the HRZ. A well-designed piloted premixed jet burner was employed to generate four turbulent premixed CH4/air jet flames, with different jet Reynolds numbers (Rejet) ranging from 4900 to 39200. The HRZ was visualized by both the gradient of OH and the pixel-by-pixel product of OH and CH2O. It is shown that turbulence has an increasing effect on the spatial structure of the flame front with an increasing height above the jet exit for the premixed jet flames, which results in the broadening of the HRZ and the increase of the wrinkling. The HRZ remains thin as the Rejet increases, whereas the preheat zone is significantly broadened and thickened. This indicates that the smallest turbulent eddies can only be able to enter the flame front rather than the HRZ in the present flame conditions. The flame quenching is observed with Rejet = 39200, which may be due to the strong entrainment of the cold air from outside of the burned gas region.

[Analysis of palliative sedation in hospitalised elderly patients: Effectiveness of a protocol].

Science.gov (United States)

Mateos-Nozal, Jesús; García-Cabrera, Lorena; Montero Errasquín, Beatriz; Cruz-Jentoft, Alfonso José; Rexach Cano, Lourdes

2016-01-01

To measure changes in the practice of palliative sedation during agony in hospitalised elderly patients before and after the implementation of a palliative sedation protocol. A retrospective before-after study was performed in hospitalised patients over 65 years old who received midazolam during hospital admission and died in the hospital in two 3-month periods, before and after the implementation of the protocol. Non-sedative uses of midazolam and patients in intensive care were excluded. Patient and admission characteristics, the consent process, withdrawal of life-sustaining treatments, and the sedation process (refractory symptom treated, drug doses, assessment and use of other drugs) were recorded. Association was analysed using the Chi(2) and Student t tests. A total of 143 patients were included, with no significant differences between groups in demographic characteristics or symptoms. Do not resuscitate (DNR) orders were recorded in approximately 70% of the subjects of each group, and informed consent for sedation was recorded in 91% before vs. 84% after the protocol. Induction and maintenance doses of midazolam followed protocol recommendations in 1.3% before vs 10.4% after the protocol was implemented (P=.02) and adequate rescue doses were used in 1.3% vs 11.9% respectively (P=.01). Midazolam doses were significantly lower (9.86mg vs 18.67mg, Psedation score was used in 8% vs. 12% and the Palliative Care Team was involved in 35.5% and 16.4% of the cases (P=.008) before and after the protocol, respectively. Use of midazolam slightly improved after the implementation of a hospital protocol on palliative sedation. The percentage of adequate sedations and the general process of sedation were mostly unchanged by the protocol. More education and further assessment is needed to gauge the effect of these measures in the future. Copyright © 2015 SEGG. Published by Elsevier Espana. All rights reserved.

Effect of environmental noise and music on dexmedetomidine-induced sedation in dogs

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Julia D. Albright

2017-07-01

Full Text Available Background Previous studies in human patients suggest depth of sedation may be affected by environmental noise or music; however, related data in domestic animals is limited. The objective of the current study was to investigate the effect of noise and music on dexmedetomidine-induced (DM- 10 µg/kg, IM sedation in 10 dogs. Methods In a crossover design, post-DM injection dogs were immediately subjected to recorded human voices at either 55–60 decibel (dB (Noise 1 or 80–85 dB (Noise 2; classical music at 45–50 dB (Music; or background noise of 40–45 dB (Control+. Control− included IM saline injection and exposure to 40–45 dB background noise. Sedation was assessed via monitoring spontaneous behavior and accelerometry (delta-g throughout three 20-min evaluation periods: baseline, noise exposure, and post-treatment. Sedation was further assessed during two restraint tests at 30 min (R1 and 40 min (R2 post-injection. A mixed model for crossover design was used to determine the effect of noise exposure and time on either spontaneous behavior scores or delta-g. The restraint scores were analyzed using a two-way repeated measures ANOVA. Results Spontaneous behavior scores indicated less sedation during Noise 2 compared to Control+ (P = 0.05. R2 restraint scores for all DM treatments except Noise 2 indicated significantly higher sedation than Control− [C+ (P = 0.003, M (P = 0.014 and N1 (P = 0.044]. Discussion Results suggest that the quality of sedation is negatively impacted by high-intensity noise conditions (80–85 dB, but exposure to music did not improve sedation in this population of research dogs.

Estabilidade térmica das vitaminas A e E em rações e premixes vitamínicos para camarões

OpenAIRE

Prado,João Paulo de Sousa; Cavalheiro,José Marcelino Oliveira; Silva,Fernanda Vanessa Gomes da; Queiroga Neto,Vicente; Bora,Pushkar Singh; Cavalheiro,Thiago Brandão

2011-01-01

O trabalho teve como objetivo avaliar a estabilidade térmica das vitaminas A e E em diferentes rações e premixes vitamínicos utilizados na carcinicultura. Foram utilizadas no experimento três rações comerciais peletilizadas e desintegradas em diferentes diâmetros e dois premixes vitamínicos. As amostras de cada dieta e de premixes foram acondicionadas em recipientes plásticos e armazenadas nas seguintes condições: ambiente refrigerado (6°C±2°C), ambiente climatizado (20°C&p...

Bispectral index monitoring for conscious sedation in intervention: better, safer, faster

Energy Technology Data Exchange (ETDEWEB)

Bell, J.K.; Laasch, H.-U.; Wilbraham, L.; England, R.E.; Morris, J.A.; Martin, D.F. E-mail: derrick.martin@smtr.nhs.uk

2004-12-01

AIM: The aim of this study was to compare subjective (Ramsay sedation score, RSS) with objective electroencephalogram-based bispectral index (BIS) assessment, and to validate the appropriate BIS range for measurement of conscious sedation in interventional procedures. MATERIALS AND METHODS: One hundred patients undergoing sedo-analgesia (midazolam and fentanyl) for interventional gastrointestinal procedures were divided into two groups. In group A (n=30) sedation was guided by the RSS with the operator blinded to the BIS recording. In group B (n=70) the operator titrated intravenous sedation to maintain an optimal BIS, predetermined from the results in group A. Recovery time, procedure duration, physiological parameters and unplanned events were recorded in both groups. RESULTS: There was a significant correlation between the BIS and RSS (p<0.001). BIS values of 87.2 and 80.9 corresponded to an RSS of 3 and 4, respectively. The optimal BIS level was defined as 80-85. Fifty-seven point five percent of readings were within this range in group B compared with 26.5% in group A (p<0.001). Sedation approaching general anaesthesia (BIS<60) occurred in 5.5% of patients in group A but not in group B. Mean recovery time, duration of procedure, midazolam and fentanyl doses were significantly reduced in group B. Unplanned events were reduced from 27 to 17%, but this was not statistically significant (p=0.29). CONCLUSION: BIS monitoring enables more effective titration of sedatives to maintain a suitable level of consciousness, whilst reducing procedure time. The BIS offers an objective, safe and reliable measure of sedation, without disturbing either patient or operator. BIS monitoring raises the standard of patient care, and in our view, should be used to augment standard assessment.

Bispectral index monitoring for conscious sedation in intervention: better, safer, faster

International Nuclear Information System (INIS)

Bell, J.K.; Laasch, H.-U.; Wilbraham, L.; England, R.E.; Morris, J.A.; Martin, D.F.

2004-01-01

AIM: The aim of this study was to compare subjective (Ramsay sedation score, RSS) with objective electroencephalogram-based bispectral index (BIS) assessment, and to validate the appropriate BIS range for measurement of conscious sedation in interventional procedures. MATERIALS AND METHODS: One hundred patients undergoing sedo-analgesia (midazolam and fentanyl) for interventional gastrointestinal procedures were divided into two groups. In group A (n=30) sedation was guided by the RSS with the operator blinded to the BIS recording. In group B (n=70) the operator titrated intravenous sedation to maintain an optimal BIS, predetermined from the results in group A. Recovery time, procedure duration, physiological parameters and unplanned events were recorded in both groups. RESULTS: There was a significant correlation between the BIS and RSS (p<0.001). BIS values of 87.2 and 80.9 corresponded to an RSS of 3 and 4, respectively. The optimal BIS level was defined as 80-85. Fifty-seven point five percent of readings were within this range in group B compared with 26.5% in group A (p<0.001). Sedation approaching general anaesthesia (BIS<60) occurred in 5.5% of patients in group A but not in group B. Mean recovery time, duration of procedure, midazolam and fentanyl doses were significantly reduced in group B. Unplanned events were reduced from 27 to 17%, but this was not statistically significant (p=0.29). CONCLUSION: BIS monitoring enables more effective titration of sedatives to maintain a suitable level of consciousness, whilst reducing procedure time. The BIS offers an objective, safe and reliable measure of sedation, without disturbing either patient or operator. BIS monitoring raises the standard of patient care, and in our view, should be used to augment standard assessment

Sedation and patient monitoring in vascular and interventional radiology

Energy Technology Data Exchange (ETDEWEB)

McDermott, V G.M.; Chapman, M E; Gillespie, I [Royal Infirmary, Edinburgh (United Kingdom)

1993-08-01

A postal survey of British and Irish interventional radiologists was carried out in 1991 to assess current practice with respect to sedation and monitoring of patients during angiography and interventional procedures. The response rate was 65%, 49% of patients are fasted prior to angiography and 68% prior to interventional procedures. Radiologists participate in obtaining consent in 60% of cases. Patients are often (50%) sedated for angiography and usually (62-94% depending on the procedure) sedated for interventional procedures. Nurses are present for most procedures, but are given the task of monitoring the patient's vital signs in only 49% of cases. Anaesthetists are present for less than 10% of interventional procedures. The findings indicate a wide variation in practice and a need to standardize practice at a uniform high level. (author).

Flow Characteristics of Multi-circular Jet Plate in Premix Chamber of Air-Assist Atomizer for Burner System

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Amirnordin Shahrin Hisham

2016-01-01

Full Text Available The flow characteristics of multi-circular jet (MCJ plate in the premix chamber of an atomizer were investigated using Computational Fluid Dynamics. Multiphase volume of fluid behavior inside the chamber was determined via steady simulations. The Eulerian–Eulerian two-fluid approach was used for execution mixing of diesel fuel and air. Spray simulation using the discrete phase with injection was generated from the nozzle hole into the ambient atmosphere. The behavior of three MCJ plates in the premix chamber was studied numerically. Results illustrated that plate open area, Ae, influenced the turbulence inside the chamber. MCJ 3, which had the lowest open area, generated the highest flow velocity and turbulence kinetic energy compared with MCJ 1 and 2. The MCJ plates could increase the turbulence in the premix chamber and contribute to the combustion efficiency.

The New MIRUS System for Short-Term Sedation in Postsurgical ICU Patients.

Science.gov (United States)

Romagnoli, Stefano; Chelazzi, Cosimo; Villa, Gianluca; Zagli, Giovanni; Benvenuti, Francesco; Mancinelli, Paola; Arcangeli, Giulio; Dugheri, Stefano; Bonari, Alessandro; Tofani, Lorenzo; Belardinelli, Andrea; De Gaudio, A Raffaele

2017-09-01

To evaluate the feasibility and safety of the MIRUS system (Pall International, Sarl, Fribourg, Switzerland) for sedation with sevoflurane for postsurgical ICU patients and to evaluate atmospheric pollution during sedation. Prospective interventional study. Surgical ICU. February 2016 to December 2016. Postsurgical patients requiring ICU admission, mechanical ventilation, and sedation. Sevoflurane was administered with the MIRUS system targeted to a Richmond Agitation Sedation Scale from -3 to -5 by adaptation of minimum alveolar concentration. Data collected included Richmond Agitation Sedation Scale, minimum alveolar concentration, inspired and expired sevoflurane fraction, wake-up times, duration of sedation, sevoflurane consumption, respiratory and hemodynamic data, Simplified Acute Physiology Score II, Sepsis-related Organ Failure Assessment, and laboratory data and biomarkers of organ injury. Atmospheric pollution was monitored at different sites: before sevoflurane delivery (baseline) and during sedation with the probe 15 cm up to the MIRUS system (S1) and 15 cm from the filter-Reflector group (S2). Sixty-two patients were enrolled in the study. No technical failure occurred. Median Richmond Agitation Sedation Scale was -4.5 (interquartile range, -5 to -3.6) with sevoflurane delivered at a median minimum alveolar concentration of 0.45% (interquartile range, 0.4-0.53) yielding a mean inspiratory and expiratory concentrations of 0.79% (SD, 0.24) and 0.76% (SD, 0.18), respectively. Median awakening time was 4 minutes (2.2-5 min). Median duration of sevoflurane administration was 3.33 hours (2.33-5.75 hr), range 1-19 hours with a mean consumption of 7.89 mL/hr (SD, 2.99). Hemodynamics remained stable over the study period, and no laboratory data indicated liver or kidney injury or dysfunction. Median sevoflurane room air concentration was 0.10 parts per million (interquartile range, 0.07-0.15), 0.17 parts per million (interquartile range, 0

Electrocardiographic, echocardiographic, and indirect blood pressure evaluation in dogs subjected to different sedation protocols

Directory of Open Access Journals (Sweden)

Helena Mondardo Cardoso

Full Text Available ABSTRACT: The present study aimed to evaluate the effects of different sedation protocols on blood pressure and echocardiographic and electrocardiographic parameters in dogs. In total, 24 male mixed-breed dogs with a mean weight of 9.87±3.0kg were used.Animals were randomly divided into four groups (n=6, which were subjected to sedation using the following protocols: acepromazine (0.05mgkg-1 and butorphanol (0.3mgkg-1 (AB; acepromazine (0.05mgkg-1and methadone (0.5mgkg-1 (AM; acepromazine (0.03mgkg-1, methadone (0.5mgkg-1, and midazolam (0.3mgkg-1(MAM; and methadone only (0.5mgkg-1 (M. Indirect blood pressure (BP measurements and computerized electrocardiography (ECG and echocardiography (ECO were performed immediately before the application of the sedation protocol (baseline, and the same evaluations were repeated after 15 minutes. BP decreased in groups AB, MAM, and AM compared to baseline values. Electrocardiographic measurements showed decreased heart rates (HRs after sedation in all groups, and bradycardia was observed after sedation in two dogs from group M and one animal from group AM. The P-wave duration increased after sedation in groups AM and M. After sedation, no changes in cardiac dimensions were revealed byECO.Fractional shortening (FS decreased after sedation in the AM group, and dogs from group AB exhibited a smaller decrease in FS compared with the other groups. The cardiac index (CI was lower in groups AM and M than in the other groups. Animals from group AB were less resistant to examination and exhibited the most favorable sedation scores. It was concluded that the combination of acepromazine and butorphanol was the best sedation protocol for performing echocardiogram measurementsbecause dogs were less resistant to examinations and echocardiographic parameters of FS and CI remained stable.

Comparison between intravenous and intramuscular administration of ketamine in children sedation referred to emergency department

Directory of Open Access Journals (Sweden)

Behnaz Boroumand Rezazadeh

2014-12-01

Full Text Available Ketamine, among wide variety of sedative drugs, has shown beneficial effects when using during the procedural sedation, specifically in pediatrics. Various parameters should be considered in order to perform a safe and effective procedural sedation including optimum dosage of the sedative, administration methods of sedation, and need for applying any adjuvant drug. In this study, we aimed to review the studies, which have compared the efficacy of the different ways of the injection of ketamine such as intravenous or intramuscular ketamine application. Based on data obtained from the related articles, efficacy and safety of these two methods of ketamine usage in the pediatric procedural sedation were widely similar, but the intravenously administration of the ketamine can be proposed as the preferable mode.

Survey of Sedation and Analgesia Practice Among Canadian Pediatric Critical Care Physicians.

Science.gov (United States)

Garcia Guerra, Gonzalo; Joffe, Ari R; Cave, Dominic; Duff, Jonathan; Duncan, Shannon; Sheppard, Cathy; Tawfik, Gerda; Hartling, Lisa; Jou, Hsing; Vohra, Sunita

2016-09-01

Despite the fact that almost all critically ill children experience some degree of pain or anxiety, there is a lack of high-quality evidence to inform preferred approaches to sedation, analgesia, and comfort measures in this environment. We conducted this survey to better understand current comfort and sedation practices among Canadian pediatric intensivists. The survey was conducted after a literature review and initial focus groups. The survey was then pretested and validated. The final survey was distributed by email to 134 intensivists from 17 PICUs across Canada using the Research Electronic Data Capture system. The response rate was 73% (98/134). The most commonly used sedation scores are Face, Legs, Activity, Cry, and Consolability (42%) and COMFORT (41%). Withdrawal scores are commonly used (65%). In contrast, delirium scores are used by only 16% of the respondents. Only 36% of respondents have routinely used sedation protocols. The majority (66%) do not use noise reduction methods, whereas only 23% of respondents have a protocol to promote day/night cycles. Comfort measures including music, swaddling, soother, television, and sucrose solutions are frequently used. The drugs most commonly used to provide analgesia are morphine and acetaminophen. Midazolam and chloral hydrate were the most frequent sedatives. Our survey demonstrates great variation in practice in the management of pain and anxiety in Canadian PICUs. Standardized strategies for sedation, delirium and withdrawal, and sleep promotion are lacking. There is a need for research in this field and the development of evidence-based, pediatric sedation and analgesia guidelines.

PREMIXED FLAME PROPAGATION AND MORPHOLOGY IN A CONSTANT VOLUME COMBUSTION CHAMBER

Energy Technology Data Exchange (ETDEWEB)

Hariharan, A; Wichman, IS

2014-06-04

This work presents an experimental and numerical investigation of premixed flame propagation in a constant volume rectangular channel with an aspect ratio of six (6) that serves as a combustion chamber. Ignition is followed by an accelerating cusped finger-shaped flame-front. A deceleration of the flame is followed by the formation of a "tulip"-shaped flame-front. Eventually, the flame is extinguished when it collides with the cold wall on the opposite channel end. Numerical computations are performed to understand the influence of pressure waves, instabilities, and flow field effects causing changes to the flame structure and morphology. The transient 2D numerical simulation results are compared with transient 3D experimental results. Issues discussed are the appearance of oscillatory motions along the flame front and the influences of gravity on flame structure. An explanation is provided for the formation of the "tulip" shape of the premixed flame front.

Dynamics and Suppression Effectiveness of Monodisperse Water Droplets in Non-Premixed Counterflow Flames

National Research Council Canada - National Science Library

Zegers, E. J; Williams, B. A; Sheinson, R. S; Fleming, J. W

2000-01-01

...-premixed propane/air counterflow flames are reported. Droplets were generated piezoelectrically, and the size and velocity distributions and the number density were determined by phase-Doppler particle anemometry...

Performance and emissions of a dual-fuel pilot diesel ignition engine operating on various premixed fuels

International Nuclear Information System (INIS)

Yousefi, Amin; Birouk, Madjid; Lawler, Benjamin; Gharehghani, Ayatallah

2015-01-01

and the higher content of oxygen with increased methanol, soot and CO emissions are significantly reduced for richer premixed methanol mixtures. According to these findings, a dual-fuel engine operating on methanol and diesel performs better at rich conditions, whereas the performance of hydrogen and diesel is superior to that of natural gas/diesel and methanol/diesel mixtures at lean conditions.

Palliative sedation at home for terminally ill children with cancer.

Science.gov (United States)

Korzeniewska-Eksterowicz, Aleksandra; Przysło, Łukasz; Fendler, Wojciech; Stolarska, Małgorzata; Młynarski, Wojciech

2014-11-01

The presence of symptoms that are difficult to control always requires adjustment of treatment, and palliative sedation (PS) should be considered. We analyzed our experience in conducting PS at home for terminally ill children with cancer during a seven-year period. We performed a retrospective analysis of medical records of children with cancer treated at home between the years 2005 and 2011. We analyzed the data of 42 cancer patients (18% of all patients); in 21 cases, PS was initiated (solid tumors n = 11, brain tumors [5], bone tumors [4], leukemia [1]). Sedation was introduced because of pain (n = 13), dyspnea (9), anxiety (5), or two of those symptoms (6). The main drug used for sedation was midazolam; all patients received morphine. There were no significant differences in the dose of morphine or midazolam depending on the patient's sex; age was correlated with an increase of midazolam dose (R = 0.68; P = 0.005). Duration of sedation (R = 0.61; P = 0.003) and its later initiation (R = 0.43; P = 0.05) were correlated with an increase of the morphine dose. All patients received adjuvant treatment; in patients who required a morphine dose increase, metoclopramide was used more often (P = 0.0002). Patients did not experience any adverse reactions. Later introduction of sedation was associated with a marginally higher number of intervention visits and a significantly higher number of planned visits (R = 0.53; P = 0.013). Sedation may be safely used at home. It requires close monitoring and full cooperation between the family and hospice team. Because of the limited data on home PS in pediatric populations, further studies are needed. Copyright © 2014 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Comparison between the Comfort and Hartwig sedation scales in pediatric patients undergoing mechanical lung ventilation

Directory of Open Access Journals (Sweden)

Werther Brunow de Carvalho

1999-09-01

Full Text Available CONTEXT: A high number of hospitalized children do not receive adequate sedation due to inadequate evaluation and use of such agents. With the increase in knowledge of sedation and analgesia in recent years, concern has also risen, such that it is now not acceptable that incorrect evaluations of the state of children's pain and anxiety are made. OBJECTIVE: A comparison between the Comfort and Hartwig sedation scales in pediatric patients undergoing mechanical lung ventilation. DESIGN: Prospective cohort study. SETTING: A pediatric intensive care unit with three beds at an urban teaching hospital. PATIENTS: Thirty simultaneous and independent observations were conducted by specialists on 18 patients studied. DIAGNOSTIC TEST: Comfort and Hartwig scales were applied, after 3 minutes of observation. MAIN MEASUREMENTS: Agreement rate (kappa. RESULTS: On the Comfort scale, the averages for adequately sedated, insufficiently sedated, and over-sedated were 20.28 (SD 2.78, 27.5 (SD 0.70, and 15.1 (SD 1.10, respectively, whereas on the Hartwig scale, the averages for adequately sedated, insufficiently sedated, and over-sedated were 16.35 (SD 0.77, 20.85 (SD 1.57, and 13.0 (SD 0.89, respectively. The observed agreement rate was 63% (p = 0.006 and the expected agreement rate was 44% with a Kappa coefficient of 0.345238 (z = 2.49. CONCLUSIONS: In our study there was no statistically significant difference whether the more complex Comfort scale was applied (8 physiological and behavioral parameters or the less complex Hartwig scale (5 behavioral parameters was applied to assess the sedation of mechanically ventilated pediatric patients.

Study of possible reduction or withdrawal of vitamin premix during ...

African Journals Online (AJOL)

The effect of dietary vitamin premix withdrawal or reduction between 29 and 35, 36 and 42, and 29 and 42 days of age on broiler chicken performance and immunocompetence was evaluated. The diets were formulated based on wheat and barley, and the experiment was conducted in floor pens (experiment 1) and battery ...

Study of possible reduction or withdrawal of vitamin premix during ...

African Journals Online (AJOL)

Jane

2011-07-06

Jul 6, 2011 ... The effect of dietary vitamin premix withdrawal or reduction between 29 and 35, 36 and 42, and 29 and. 42 days of age on broiler chicken performance and immunocompetence was evaluated. The diets were formulated based on wheat and barley, and the experiment was conducted in floor pens ...

Attitudes towards terminal sedation: an empirical survey among experts in the field of medical ethics

Directory of Open Access Journals (Sweden)

Hinz José

2007-04-01

Full Text Available Abstract Background "Terminal sedation" regarded as the use of sedation in (pre-terminal patients with treatment-refractory symptoms is controversially discussed not only within palliative medicine. While supporters consider terminal sedation as an indispensable palliative medical treatment option, opponents disapprove of it as "slow euthanasia". Against this background, we interviewed medical ethics experts by questionnaire on the term and the moral acceptance of terminal sedation in order to find out how they think about this topic. We were especially interested in whether experts with a professional medical and nursing background think differently about the topic than experts without this background. Methods The survey was carried out by questionnaire; beside the provided answering options free text comments were possible. As test persons we chose the 477 members of the German Academy for Ethics in Medicine, an interdisciplinary society for medical ethics. Results 281 completed questionnaires were returned (response rate = 59%. The majority of persons without medical background regarded "terminal sedation" as an intentional elimination of consciousness until the patient's death occurs; persons with a medical background generally had a broader understanding of the term, including light or intermittent forms of sedation. 98% of the respondents regarded terminal sedation in dying patients with treatment-refractory physical symptoms as acceptable. Situations in which the dying process has not yet started, in which untreatable mental symptoms are the indication for terminal sedation or in which life-sustaining measures are withdrawn during sedation were evaluated as morally difficult. Conclusion The survey reveals a great need for research and discussion on the medical indication as well as on the moral evaluation of terminal sedation. Prerequisite for this is a more precise terminology which describes the circumstances of the sedation.

Dynamics of flow–soot interaction in wrinkled non-premixed ethylene–air flames

KAUST Repository

Arias, Paul G.; Lecoustre, Vivien R.; Roy, Somesh; Luo, Zhaoyu; Haworth, Daniel C.; Lu, Tianfeng; Trouvé , Arnaud; Im, Hong G.

2015-01-01

A two-dimensional simulation of a non-premixed ethylene–air flame was conducted by employing a detailed gas-phase reaction mechanism considering polycyclic aromatic hydrocarbons, an aerosol-dynamics-based soot model using a method of moments

Palliative sedation in Germany: factors and treatment practices associated with different sedation rate estimates in palliative and hospice care services.

Science.gov (United States)

Stiel, Stephanie; Nurnus, Mareike; Ostgathe, Christoph; Klein, Carsten

2018-03-13

Clinical practice of Palliative Sedation (PS) varies between institutions worldwide and sometimes includes problematic practices. Little available research points at different definitions and frameworks which may contribute to uncertainty of healthcare professionals in the application of PS. This analysis investigates what demographic factors and characteristics of treatment practices differ between institutions with high versus low sedation rates estimates in Palliative and Hospice Care in Germany. Data sets from 221 organisations from a prior online survey were separated into two sub-groups divided by their estimated sedation rate A) lower/equal to 16% (n = 187; 90.8%) and B) higher than 16% (n = 19; 9.2%) for secondary analysis. Demographic factors and characteristics of PS treatment practices between the two groups were compared using T-Tests and Chi 2 / Fisher Exact Tests and considered significant (*) at two-sided p palliative and hospice care representatives show divergence, which may be influenced one by another. A comprehensive framework considering conceptual, clinical, ethical, and legal aspects of different definitions of PS could help to better distinguish between different types and nuances of PS.

Current role of non-anesthesiologist administered propofol sedation in advanced interventional endoscopy

DEFF Research Database (Denmark)

Burtea, Daniela Elena; Dimitriu, Anca; Maloş, Anca Elena

2015-01-01

the patients and medical personnel. Current guidelines support the use of propofol sedation, which has the same rate of adverse effects as traditional sedation with benzodiazepines and/or opioids, but decreases the procedural and recovery time. Non-anesthesiologist administered propofol sedation has become......, improved satisfaction for patients and doctors, as well as decreased recovery and discharge time. Despite the advantages of non-anesthesiologist administered propofol, there is still a continuous debate related to the successful generalization of the procedures....

Transient combustion modeling of an oscillating lean premixed methane/air flam

NARCIS (Netherlands)

Withag, J.A.M.; Kok, Jacobus B.W.; Syed, Khawar

2009-01-01

The main objective of the present study is to demonstrate accurate low frequency transient turbulent combustion modeling. For accurate flame dynamics some improvements were made to the standard TFC combustion model for lean premixed combustion. With use of a 1D laminar flamelet code, predictions

Low and High Temperature Combustion Chemistry of Butanol Isomers in Premixed Flames and Autoignition Systems

Energy Technology Data Exchange (ETDEWEB)

Sarathy, S M; Pitz, W J; Westbrook, C K; Mehl, M; Yasunaga, K; Curran, H J; Tsujimura, T; Osswald, P; Kohse-Hoinghaus, K

2010-12-12

Butanol is a fuel that has been proposed as a bio-derived alternative to conventional petroleum derived fuels. The structural isomer in traditional 'bio-butanol' fuel is n-butanol, but newer conversion technologies produce iso-butanol as a fuel. In order to better understand the combustion chemistry of bio-butanol, this study presents a comprehensive chemical kinetic model for all the four isomers of butanol (e.g., 1-, 2-, iso- and tert-butanol). The proposed model includes detailed high temperature and low temperature reaction pathways. In this study, the primary experimental validation target for the model is premixed flat low-pressure flame species profiles obtained using molecular beam mass spectrometry (MBMS). The model is also validated against previously published data for premixed flame velocity and n-butanol rapid compression machine and shock tube ignition delay. The agreement with these data sets is reasonably good. The dominant reaction pathways at the various pressures and temperatures studied are elucidated. At low temperature conditions, we found that the reaction of alphahydroxybutyl with O{sub 2} was important in controlling the reactivity of the system, and for correctly predicting C{sub 4} aldehyde profiles in low pressure premixed flames. Enol-keto isomerization reactions assisted by HO{sub 2} were also found to be important in converting enols to aldehydes and ketones in the low pressure premixed flames. In the paper, we describe how the structural features of the four different butanol isomers lead to differences in the combustion properties of each isomer.

[Palliative sedation at a university palliative care unit--a descriptive analysis].

Science.gov (United States)

Hopprich, A; Günther, L D; Laufenberg-Feldmann, R; Reinholz, U; Weber, M

2016-04-01

Palliative sedation (pS) is indicated in the presence of end-stage disease with treatment-refractory symptoms not tolerable for the patient. We investigated the practice of pS at a university palliative care unit. Before starting pS the following data were documented: indication and decision making, type of sedation, life expectancy evaluated by the physician using the palliative prognostic index. Over the time of pS communication skills, depth of sedation, relief in symptoms, substitution of fluid and nutrition and used medications were collected. During evaluation time 99 patients died. 34 patients received pS (34 %). All patients suffered from cancer. Indications for palliative sedation were: terminal restlessness (56 %), dyspnea (39 %), pain (32 %), psychological distress (15 %), agitated delir (9 %), vomiting (3 %) and bleeding (3 %) (multiple nominations possible). In 31 cases (91 %) nurses were included for decision making. In 33 cases continuous sedation were initiated immediately (median duration 27.5 hours). The most applied medication was midazolam (94 %), sometimes combined with neuroleptics (44 %) and propofol (15 %). 91 % of the patients additionally received opioids. Artificial fluid was substituted in two cases. Palliative sedation started in the median 27.5 hours before death. The final physician assessment revealed complete symptom relief in 12 patients (35 %), very strong symptom relief in 20 patients (59 %) and moderate symptom relief in 2 patients (6 %). pS was successfully used as last resort for relief of treatment-refractory symptoms in one third of decedents at the investigated palliative care unit. © Georg Thieme Verlag KG Stuttgart · New York.

Feasibility of measuring memory response to increasing dexmedetomidine sedation in children.