Valanne, Jukka V.; Korttila, Kari
Anesthesia was induced in 120 unpremedicated, healthy patients undergoing outpatient dentistry or oral surgery with methohexital, and endotracheal intubation facilitated with succinylcholine. Anesthesia was maintained randomly with either enflurane or isoflurane in nitrous oxide and oxygen (50%) administered in a nonrebreathing circuit using spontaneous respiration. After both enflurane and isoflurane anesthesia, it took 12-13 minutes before the patients were oriented as to time and place. Th...
Madsen, J.B.; Cold, G.E.; Eriksen, H.O.; Eskesen, V.; Blatt-Lyon, B.
In 14 patients with supratentorial cerebral tumours with midline shift ≤ 10 mm, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo 2 ) were measured twice on the contralateral side of the craniotomy, using a modification of the Kety and Schmidt method. For induction of anaesthesia, thiopental, fentanyl and pancuronium were used. The anaesthesia was maintained with enflurane 1% in nitrous oxide 67%. Moderate hypocapnia to a level averaging 4.3 kPa was achieved. The patients were divided into two groups. In group 1 (n=7), 1% enflurane was used throughout the anaesthesia, and CBF and CMRo 2 measured about 70 min after induction averaged 30.1 ml 100 g -1 min -1 and 1.98 ml O 2 100 g -1 min -1 , respectively. During the second CBF study 1 h later, CBF and CMRo 2 were unchanged (P>0.05). In group 2 (n=7), the inspiratory enflurane concentration was increased from 1 to 2% after the first CBF measurement. In this group a significant decrease in CMRo 2 was observed, while CBF was unchanged. In six patients EEG was recorded simultaneously with the CBF measurements. In patients subjected to increasing enflurane concentration (Group 2), a suppression in the EEG activity was observed without spike waves. It is concluded that enflurane induces a dose-related decrease in CMRo 2 and suppression in the EEG activity, whereas CBF was unchanged (author)
Vandesteene, A; Mouawad, E; Noterman, J; Deloof, T; Ewalenko, P; Genette, F
In patients operated for cerebral aneurysm or angioma, the same basic method of anesthesia has been used. Premedication consisted of Thalamonal or diazepam. After induction with thiopentone, curarisation with pancuronium and tracheal intubation, anesthesia was maintained with N2O 70%, O2 30% and enflurane 1%. Small doses of fentanyl or Thalamonal were given at the beginning of anesthesia, but no more within 30 minutes before starting controlled hypotension. Adjuvant drugs and methods to reduce intracranial pressure were also used, such as dexamethasone, mannitol and cerebro-spinal fluid subtraction. The approach and dissection of the vascular lesion was done under controlled hypotension with sodium nitroprusside 0.01% solution. The mean dose of sodium nitroprusside to maintain a mean blood pressure at about 50 Torr was 1.37 mcg/kg/min.
Madsen, J.B.; Cold, G.E.; Eriksen, H.O.; Eskesen, V.; Blatt-Lyon, B.
In 14 patients with supratentorial cerebral tumors with midline shift less than or equal to 10 mm, cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRo/sub 2/) were measured twice on the contralateral side of the craniotomy, using a modification of the Kety and Schmidt method. For induction of anaesthesia, thiopental, fentanyl and pancuronium were used. The anaesthesia was maintained with enflurane 1% in nitrous oxide 67%. Moderate hypocapnia to a level averaging 4.3 kPa was achieved. The patients were divided into two groups. In group 1 (n=7), 1% enflurane was used throughout the anaesthesia, and CBF and CMRo/sub 2/ measured about 70 min after induction averaged 30.1 ml 100 g/sup -1/ min/sub -1/ and 1.98 ml O/sub 2/ 100 g/sup -1/ min/sup -1/, respectively. During the second CBF study 1 h later, CBF and CMRo/sub 2/ were unchanged (P>0.05). In group 2 (n=7), the inspiratory enflurane concentration was increased from 1 to 2% after the first CBF measurement. In this group a significant decrease in CMRo/sub 2/ was observed, while CBF was unchanged. In six patients EEG was recorded simultaneously with the CBF measurements. In patients subjected to increasing enflurane concentration (Group 2), a suppression in the EEG activity was observed without spike waves. It is concluded that enflurane induces a dose-related decrease in CMRo/sub 2/ and suppression in the EEG activity, whereas CBF was unchanged.
Eintrei, C.; Leszniewski, W.; Carlsson, C.
It is well known that halothane causes an increase in cerebral blood flow (CBF). In this study the effects of halothane, enflurane, and isoflurane on regional cerebral blood flow (rCBF) in humans were determined in the presence of 70% N 2 O at a combined MAC concentration of 1.5. CBF was determined in 24 patients from the washout of locally applied 133 Xenon with the use of an external scintillation. All 24 patients (control n = 6, halothane n = 6, enflurane n = 6, and isoflurane n = 6) were undergoing neurosurgical procedures. All patients were anesthetized with thiopental, fentanyl, droperidol, and 70% N 2 O in oxygen and paralyzed with pancuronium. The measurements were performed after the dura had been opened and before definitive surgery. The first measurement was done in the absence of any volatile agent, and the wash-out curve was registered for 6 min. The second measurement was done after one of the volatile agents had been added for at least 20 min and had reached a concentration of 0.58% for halothane, 1.14% for enflurane, or 1.0% for isoflurane in the expiratory gases in order to obtain about 1.5 MAC with each volatile anesthetic. The anesthetic concentrations were measured with the Engstroem multigas analyzer EMMA. The physiologic variables changed very little throughout the period of observation. Body temperature, heart rate, blood pressure, PaCO 2 , and PaO 2 were stable. Ephedrine was used to maintain a stable arterial pressure. At approximately 1.5 MAC, halothane (plus N 2 O) increased rCBF to nearly three times (166%) the control value, while enflurane induced only a slight increase (35%) in rCBF
Bischoff, P; Plümer, L; Scholz, J; Drögemeier, K; von Knobelsdorff, G; Schulte am Esch, J
Electrophysiological parameters are well-suited to detect changes in cerebral function. The present study investigates whether balanced anaesthesia with remifentanil during nociceptive stimulation is associated with changes in clinical and electrophysiological parameters indicating inadequate depth of anaesthesia. Following IRB approval and written informed consent, 23 patients (ASA: I; age: 36 +/- 11) scheduled for elective gynaecological laparoscopy were included in the study. Without any premedication, anaesthesia was induced with remifentanil (1.0 microgram/kg bolus injection), propofol (0.5 mg/kg added by repetitive (10 mg) bolus injections every 10 s until unconciousness) and vecuronium (0.1 mg/kg). Following endotracheal intubation (normoventilation: PetCO2: 36 bis 38 mmHg), remifentanil infusion was started with continuous doses of 0.5 microgram/kg/min over 5 minutes and maintained with 0.25 microgram/kg/min during surgery. Remifentanil was randomly combined with propofol (group 1: 100 micrograms/kg/min; n = 7), enflurane (group 2: 0.5 MAC; n = 8) or isoflurane (group 3: 0.5 MAC; n = 8). Monitoring included: heart rate (beats/min), mean arterial pressure (mmHg), oxygen saturation (%), endtidal CO2 (mmHg) and endtidal enflurane and isoflurane (%). EEG: 2-channel recordings of Fz versus mastoid and ECG (artefact control) during steady-state anaesthesia and surgery. Following fast-fourier-transformation (4 s; 256/s; 0.5 to 35.0 Hz), spectral power densities were calculated for the selected frequency bands. Auditory evoked potentials (AEP; middle latency) were registered simultaneously after binaural stimulation via head-phones click-stimulation (6 Hz; 75 dB above hearing threshold; 512 stimulations per average). Bandpass was 0.01 to 2.0 kHz. Na, Pa, Nb (latencies; ms) and peak-to-peak amplitudes (NaPa, PaNb; microV). EEG and AEP recording technique . The study protocol included baseline values from pre-intubation, pre-surgery, the respective post
Freye, E; Knüfermann, V
Postoperative intestinal atonia is a complication which is likely to occur in patients predisposed for constipation and in patients after intra-abdominal operations. The postoperative delay of bowel movement, however, is often also related to the type of anaesthesia being used. In order to evaluate the magnitude of an anaesthetic-induced postoperative delay of bowel movement, two types of intravenous-based anaesthesia using fentanyl/midazolam (1 mg/25 mg; dosage 0.1 ml/kg/h), and ketamine/midazolam (250 mg/25 mg; dosage 0.1 ml/kg/h) respectively were compared with a volatile anaesthetic technique (enflurane; mean concentration 1.5 vol%). METHODS. In three groups of patients (each n = 15) undergoing elective surgery of the lower extremities, induction of anaesthesia was accomplished with methohexital (1-1.5 mg/kg) to facilitate intubation. For the maintenance of muscle relaxation vecuronium bromide was used. All patients were given droperidol to prevent postoperative emesis, and they were artificially ventilated with N2O/O2 (60:40) to normal end-expiratory CO2 concentrations. No anticholinergic agents were used at the end of operation since they are known to interfere with bowel motility. In order to determine gastro-intestinal motility, the H2 exhalation test was used. For this purpose 40 g lactulose in 100 ml of water was given to all patients via a gastral tube shortly before extubation. Lactulose is broken down by bacteria once it enters the colon, and H2 is released, taken up by the vascular system and exhaled. Postoperatively, patients were asked to exhale into a 20-ml syringe every 10 min. The content was analysed for hydrogen (ppm), using an electrochemical sensor (GMI exhaled hydrogen monitor). From the time of lactulose instillation to a threefold increase in end-expiratory hydrogen concentration (compared to the preoperative value), gastro-coecal transit time was computed. RESULTS. All three groups of patients were comparable in age, height and body
Manohar, M.; Parks, C.
Fifteen micron diameter radionuclide labelled microspheres were injected into left atrium; and cerebral, myocardial, renal, adrenal and splanchnic organ hemodynamics were studied in nine healthy, isocapnic, normothermic swine while awake and during two levels (1.0 and 1.5 MAC) of anesthesia produced with halothane (HAL) vaporized in O 2 alone and a mixture of 50% nitrous oxide in O 2 . Heart rate, cardiac output and arterial blood pressure were maintained better when equipotent anesthesia was produced using 50% N 2 O with HAL. Dose dependent vasodilatation occurred with HAL in all regions of the brain. Cerebral, cerebellar and brain stem blood flows at 1.5 MAC HAL-O 2 were 135, 135 and 115% of respective control values. At 1.0 and 1.5 MAC, HAL-N 2 O cerebral blood flow was 204 and 153% of awake values. These effects on cerebral circulation were similar directionally to those of equipotent isoflurane and enflurane anesthesia. However, sevoflurane-O 2 did not cause cerebral vasodilation. Myocardial blood flow decreased transmurally with HAL-O 2 but during equipotent HAL-N 2 O anesthesia it was not different from the awake value. Renal blood flow was unaffected during both levels of HAL-O 2 and HAL-N 2 O anesthesia. Adrenal blood flow increased with 1.5 MAC HAL-O 2 . Splenic, pancreatic, gastric and small intestinal blood flows decreased with HAL-O 2 and HAL-N 2 O anesthesia. During HAL-N 2 O anesthesia, perfusion to these tissues was above values recorded during equipotent HAL-O 2 anesthesia
Alterações transitórias do exame neurológico durante o despertar da anestesia com enflurano, isoflurano ou sevoflurano Alteraciones transitorias del examen neurológico durante el despertar de la anestesia con enflurano, isoflurano o sevoflurano Transient neurological changes during emergence from enflurane, isoflurane or sevoflurane anesthesia
Luiz Fernando Soares
comportamiento durante la recuperación de la anestesia con enflurano (Grupo E, isoflurano (Grupo I y sevoflurano (Grupo S. MÉTODO: Fueron estudiados 44 pacientes que recibieron anestesia con enflurano, isoflurano o sevoflurano en N2O a 50%. Fueron anotados antes de la inducción, inmediatamente después de la cesación de la administración del anestésico y 5, 10, 15, 20, 30 e 40 minutos después: temperatura timpánica, nivel de consciencia, tono muscular, reflejos pupilar, ciliar, bicipital, patelar y cutaneo-plantar, bien como la ocurrencia de calofríos. RESULTADOS: Las respuestas de los reflejos pupilar, ciliar, patelar y cutaneo-plantar se correlacionaron con el nivel de consciencia. Los grupos no difirieron cuanto a la prevalencia de hipertonia muscular, hiperreflexia bicipital, clonus plantar y respuesta extensora cutaneo-plantar. Hiperreflexia patelar fue mas frecuente en el grupo del enflurano de que en el grupo del isoflurano. Calofríos fueron mas frecuentes en los grupos E e I de que en el grupo del sevoflurano. La temperatura timpánica no difirió entre los pacientes que presentaron o no calofríos. CONCLUSIONES: Alteraciones reversibles del examen neurológico pueden estar presentes por hasta 40 minutos durante la recuperación de la anestesia con enflurano, isoflurano o sevoflurano.BACKGROUND AND OBJECTIVES: Transient neurological findings are seen during emergence from halothane, enflurane, and isoflurane anesthesia. Little is known about neurological changes during recovery from sevoflurane anesthesia. This study was aimed at comparing the incidence of such findings during recovery from enflurane (Group E, isoflurane (Group I and sevoflurane (Group S anesthesia. METHODS: Forty four patients were assigned to receive enflurane, isoflurane or sevoflurane anesthesia in 50% N2O. Evaluated parameters were: tympanic temperature, consciousness level, muscle tone, pupillary, eyelash, bicipital, patellar and plantar reflexes and shivering, which were recorded before
Zierkiewicz, W.; Zalesny, R.; Hobza, Pavel
Roč. 15, č. 16 (2013), s. 6001-6007 ISSN 1463-9076 Institutional support: RVO:61388963 Keywords : shifting hydrogen-bonds * center-dot-o * molecular-orbital methods Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.198, year: 2013
Zierkiewicz, W.; Wieczorek, R.; Hobza, Pavel; Michalska, D.
Roč. 13, č. 11 (2011), s. 5105-5113 ISSN 1463-9076 R&D Projects: GA MŠk LC512 Institutional research plan: CEZ:AV0Z40550506 Keywords : halogen bond * anaesthetics * ab initio calculation Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 3.573, year: 2011
Pedersen, C M; Stjernholm, P H; Hansen, T G
On the basis of a review of the literature, a survey is presented concerning the use of halogenated inhalational anaesthetics (halothane, enflurane, isoflurane) in anaesthesia of asthmatic patients and in intensive care units in the treatment of status asthmaticus refractory to maximal standard t...
were anesthetized with isoflurane (4% induction and 2.0-2.5% maintenance ) and placed in a stereotactic frame. A small amount of petrolatum was placed...28 days after focal ischemia. Mice were anesthetized with enflurane (4% induction and 1.5- 2% maintenance ) and placed in a stereotactic frame...Photon Max 512B, Princeton Instruments) connected to a tandem lens system (two 25-mm f/0.95 Cosmicar/Pentax CCTV lenses, attached front to front, 1X
Carbon monoxide production from five volatile anesthetics in dry sodalime in a patient model: halothane and sevoflurane do produce carbon monoxide; temperature is a poor predictor of carbon monoxide production
Perez Roberto SGM
Full Text Available Abstract Background Desflurane and enflurane have been reported to produce substantial amounts of carbon monoxide (CO in desiccated sodalime. Isoflurane is said to produce less CO and sevoflurane and halothane should produce no CO at all. The purpose of this study is to measure the maximum amounts of CO production for all modern volatile anesthetics, with completely dry sodalime. We also tried to establish a relationship between CO production and temperature increase inside the sodalime. Methods A patient model was simulated using a circle anesthesia system connected to an artificial lung. Completely desiccated sodalime (950 grams was used in this system. A low flow anesthesia (500 ml/min was maintained using nitrous oxide with desflurane, enflurane, isoflurane, halothane or sevoflurane. For immediate quantification of CO production a portable gas chromatograph was used. Temperature was measured within the sodalime container. Results Peak concentrations of CO were very high with desflurane and enflurane (14262 and 10654 ppm respectively. It was lower with isoflurane (2512 ppm. We also measured small concentrations of CO for sevoflurane and halothane. No significant temperature increases were detected with high CO productions. Conclusion All modern volatile anesthetics produce CO in desiccated sodalime. Sodalime temperature increase is a poor predictor of CO production.
volunteers, 5. Horan BF, 1’rys-Roberts C, Hamilton WK, Roberts IG. Hie- I’ac2 rturnd t ner omalvalus, ut ardivas irodyftamic responses to enflurane anaesthesia...prolonged mainte- 77-81. nance of anesthesia. 19. Henry RI, Cannon DC., Winktlinail 1W, eds. (li ilheinitry,principles anid techiniques. 2nd ed. New York I...spinal cord injuries, particularly in the cervical or high thoracic regions, result in a "spinal shock" syndrome . Large volumes of intravenous fluid may
Christensen, P L; Nielsen, J; Kann, T
A simple procedure for making calibration mixtures of oxygen and the anesthetic gases isoflurane, enflurane, and halothane is described. One to ten grams of the anesthetic substance is evaporated in a closed, 11,361-cc glass bottle filled with oxygen gas at atmospheric pressure. The carefully mixed gas is used to calibrate anesthetic gas monitors. By comparison of calculated and measured volumetric results it is shown that at atmospheric conditions the volumetric behavior of anesthetic gas mixtures can be described with reasonable accuracy using the ideal gas law. A procedure is described for calculating the deviation from ideal gas behavior in cases in which this is needed.
Tverskoy, M.; Gelman, S.; Fowler, K.C.; Bradley, E.L.
This study was designed to evaluate the influence of inhalational agents on the intestinal circulation in an isolated loop preparation. Sixty dogs were studied, using three intestinal segments from each dog. Selected intestinal segments were pumped with aortic blood at a constant pressure of 100 mmHg. A mixture of 86 Rb and 9-microns spheres labeled with 141 Ce was injected into the arterial cannula supplying the intestinal loop, while mesenteric venous blood was collected for activity counting. A very strong and significant correlation was found between rubidium clearance and microsphere entrapment (r = 0.97, P less than 0.0001). Nitrous oxide anesthesia was accompanied by a higher vascular resistance (VR), lower flow (F), rubidium clearance (Cl-Rb), and microspheres entrapment (Cl-Sph) than pentobarbital anesthesia, indicating that the vascular bed in the intestinal segment was constricted and flow (total and nutritive) decreased. Halothane, enflurane, and isoflurane anesthesia were accompanied by a much lower arteriovenous oxygen content difference (AVDO 2 ) and oxygen uptake than pentobarbital or nitrous oxide. Compared with pentobarbital, enflurane anesthesia was not accompanied by marked differences in VR, F, Cl-Rb, and Cl-Sph; halothane at 2 MAC decreased VR and increased F and Cl-Rb while isoflurane increased VR and decreased F. alpha-Adrenoceptor blockade with phentolamine (1 mg . kg-1) abolished isoflurane-induced vasoconstriction, suggesting that the increase in VR was mediated via circulating catecholamines
Vollmar, B; Conzen, P F; Kerner, T; Habazettl, H; Vierl, M; Waldner, H; Peter, K
The object of this investigation was to compare the effects of volatile anesthetics and of hemorrhage at comparable arterial blood pressures on splanchnic blood flow (radioactive microspheres) and tissue oxygenation of the liver and pancreas (surface PO2 [PSO2] electrodes). In contrast to earlier studies, we did not use identical minimum alveolar anesthetic concentration multiples as a reference to compare volatile anesthetics; rather, we used the splanchnic perfusion pressure. Under general anesthesia (intravenous chloralose) and controlled ventilation, 12 Sprague-Dawley rats underwent laparotomy to allow access to abdominal organs. Mean arterial pressure was decreased from 84 +/- 3 mm Hg (mean +/- SEM) at control to 50 mm Hg by 1.0 +/- 0.1 vol% halothane, 2.2 +/- 0.2 vol% enflurane, and 2.3 +/- 0.1 vol% isoflurane in a randomized sequence. For hemorrhagic hypotension, blood was withdrawn gradually until a mean arterial pressure of 50 mm Hg was attained. Volatile anesthetics and hemorrhage reduced cardiac output, and hepatic arterial, portal venous, and total hepatic blood flows by comparable degrees. Mean hepatic PSO2 decreased significantly from 30.7 +/- 2.6 mm Hg at control to 17.4 +/- 2 and 17.5 +/- 2 mm Hg during enflurane and isoflurane (each P less than 0.05) anesthesia, respectively. The decrease to 11.5 +/- 2.5 mm Hg was more pronounced during halothane anesthesia. Hemorrhagic hypotension was associated with the lowest hepatic PSO2 (3.4 +/- 1.3 mm Hg) and the highest number of hypoxic (0-5 mm Hg 86%) and anoxic PSO2 values (0 mm Hg 46%). Pancreatic blood flow and oxygenation remained unchanged from control during halothane and enflurane administration, whereas isoflurane increased both variables. Hemorrhagic hypotension slightly reduced pancreatic flow (-8%) but significantly decreased PSO2 from 58 +/- 5 mm Hg at control to 36 +/- 3 mm Hg, with 7% of all measured values in the hypoxic range. Thus, volatile anesthetics preserved pancreatic but not hepatic
Dahl, J B; Daugaard, J J; Rasmussen, B
with bupivacaine 7.5 mg.ml-1, 2 ml. General anaesthesia was induced with thiopentone, pancuronium or atracurium, and fentanyl 0.1-0.3 mg, and maintained with N2O/O2 and enflurane. The epidural regimen consisted of a bolus of 16 ml of bupivacaine 7.5 mg.ml-1 plus morphine 2 mg, and continuous infusion...... of bupivacaine 1.25 mg.ml-1 plus morphine 0.05 mg.ml-1, 4 ml.h-1 for the first 24 h, and bupivacaine 0.625 mg.ml-1 plus morphine 0.05 mg.ml-1, 4 ml.h-1, for the next 24 h after operation. Additional morphine 2.5-5 mg was administered i.v. or i.m. for the first 24 h postoperatively, and ketobemidone or morphine 5...
Costa, D L; Lehmann, J R; Harold, W M; Drew, R T
A fiberoptic laryngoscope which allows direct visualization of the deep pharynx and epiglottis has been developed for transoral tracheal intubation of small laboratory mammals. The device has been employed in the intubation and instillation of a variety of substances into the lungs of rats, and with minor modification, has had similar application in mice, hamsters, and guinea pigs. The simplicity and ease of handling of the laryngoscope permits one person to intubate large numbers of enflurane anesthetized animals either on an open counter top or in a glove-box, as may be required for administration of carcinogenic materials. Instillation of 7Be-labeled carbon particles into the lungs of mice, hamsters, rats, and guinea pigs resulted in reasonably consistent interlobal distribution of particles for each test animal species with minimal tracheal deposition. However, actual lung tissue doses of carbon exhibited some species dependence.
Kuć, Marta; Cieślik-Boczula, Katarzyna; Rospenk, Maria
The influence of cholesterol on the structure of the model lipid bilayers treated with inhalation anesthetics (enflurane, isoflurane, sevoflurane and halothane) was investigated employing near-infrared (NIR) spectroscopy combined with the Principal Component Analysis (PCA). The conformational changes occurring in the hydrophobic area of the lipid bilayers were analyzed using the first overtones of symmetric (2νs) and antisymmetric (2νas) stretching vibrations of the CH2 groups of lipid aliphatic chains. The temperature values of chain-melting phase transition (Tm) of anesthetic-mixed dipalmitoylphosphatidylcholine (DPPC)/cholesterol and dipalmitoylphosphatidylglycerol (DPPG)/cholesterol membranes, which were obtained from the PCA analysis, were compared with cholesterol-free DPPC and DPPG bilayers mixed with inhalation anesthetics.
Stutler, Shannon A; Johnson, Eric W; Still, Kenneth R; Schaeffer, David J; Hess, Rex A; Arfsten, Darryl P
Euthanasia is one of the most commonly performed procedures in laboratory animal settings. The method of euthanasia may affect experimental results in studies using animals and must be compatible with research objectives including subsequent tissue analyses. Our present study was performed to evaluate the effects of 7 euthanasia methods on sperm motility in mature rats. Rats were euthanized using CO2, 2 commercially available euthanasia solutions (Beuthanasia-D and Sleepaway), and 4 volatile anesthetics (enflurane, halothane, isoflurane, and sevoflurane). Rats euthanized by rapid decapitation alone served as negative controls, and a-chlorohydrin-treated rats euthanized by rapid decapitation were positive controls for sperm impairment. For 5 of these methods, we also measured time to ataxia, recumbency, respiratory arrest, and no auscultable heartbeat. Immediately after euthanasia of each rat, distal caudal epididymides were removed; 1 was processed for automated sperm motility analysis, and the other was frozen for subsequent concentration analysis. Time to all measured parameters was less for volatile anesthetics than for Beuthanasia-D. Times to last respiration and no heartbeat were less for halothane and isoflurane than for enflurane and sevoflurane. Percentage motile sperm did not differ significantly between methods. Percentage progressively motile sperm did not vary significantly between methods except for Beuthanasia-D, for which it was significantly less than the negative control value. Specific sperm motion parameters for each euthanasia method except CO2 and Sleepaway varied significantly from the negative control. Our results indicate that the method of euthanasia is an important consideration when rat sperm motility parameters must be evaluated.
Hamid, Tahir; Rose, Samman; Horner, Simon
Congenital coronary anomalies are uncommon and are usually diagnosed incidentally during coronary angiogram or autopsy. Isolated coronary artery anomalies and the anomalous origin of left main stem (LMS) from the proximal portion of the right coronary artery or from the right sinus of valsalva are extremely rare. A 68 years old woman with atypical chest pains was referred for risk assessment for the general anaesthesia. A stress exercise treadmill test and myocardial perfusion scan revealed evidence of mild myocardial ischemia. Her coronary angiography revealed her left coronary artery to have a single origin with the right coronary artery. There were no flowlimiting lesions. A CT aortography confirmed a retro-aortic course of the left coronary artery. She successfully underwent multiple surgical procedures under general anaesthesia including total abdominal hysterectomy, Burch colposuspension (twice) for stress incontinence, intravesical botox injection for urge incontinence and haemorrhoidectomy for recurrent rectal mucosal prolapse. Various anaesthetic agents including halothane, thiopentone, suxamethonium, pancuronium, enflurane, fentanyl, propofol and isoflurane were used without any adverse clinical consequences. She remained well on 48 months follow-up.
Zhou, Miaomiao; Xia, Huimin; Xu, Younian; Xin, Naixing; Liu, Jiao; Zhang, Shihai
Although empirically well understood in their clinical administration, volatile anesthetics are not yet well comprehended in their mechanism studies. A major conundrum emerging from these studies is that there is no validated model to assess the presumed candidate sites of the anesthetics. We undertook this study to test the hypothesis that the single-celled Paramecium could be anesthetized and served as a model organism in the study of anesthetics. We assessed the motion of Paramecium cells with Expert Vision system and the chemoresponse of Paramecium cells with T-maze assays in the presence of four different volatile anesthetics, including isoflurane, sevoflurane, enflurane and ether. Each of those volatiles was dissolved in buffers to give drug concentrations equal to 0.8, 1.0, and 1.2 EC50, respectively, in clinical practice. We could see that after application of volatile anesthetics, the swimming of the Paramecium cells was accelerated and then suppressed, or even stopped eventually, and the index of the chemoresponse of the Paramecium cells (denoted as I ( che )) was decreased. All of the above impacts were found in a concentration-dependent fashion. The biphasic effects of the clinical concentrations of volatile anesthetics on Paramecium simulated the situation of high species in anesthesia, and the inhibition of the chemoresponse also indicated anesthetized. In conclusion, the findings in our studies suggested that the single-celled Paramecium could be anesthetized with clinical concentrations of volatile anesthetics and therefore be utilized as a model organism to study the mechanisms of volatile anesthetics.
PURPOSE: Videoscopic herniorrhaphy is being performed more frequently with advantages claimed over the conventional open approach. This clinical report describes a pneumothorax, pneumomediastinum and subcutaneous emphysema occurring at the end of an extraperitoneal videoscopic herniorrhaphy. CLINICAL FEATURES: A 25 yr old ASA I man presented for elective extraperitoneal videoscopic hernia repair. Following intravenous induction with fentanyl, midazolam and propofol a balanced anesthetic technique using enflurane in N2O and O2 was used. Apart from a prolonged operating time (195 min), the procedure and anesthetic was uneventful. At the conclusion of the operation, prior to reversal of neuromuscular blockade extensive subcutaneous emphysema was noted on removal of the surgical drapes. Chest radiography revealed a pneumomediastinum and pneumothorax. A 25 FG intercostal tube was inserted and connected to an underwater seal drain. Sedation and positive pressure ventilation was maintained overnight to permit resolution and avoid airway compromise. The clinical and radiological features had resolved by the next morning and the patient\\'s trachea was extubated. His subsequent recovery was uneventful. CONCLUSION: Pneumothorax and pneumomediastinum are well recognised complications of laparoscopic techniques but have not been described following extraperitoneal herniorrhaphy. In this report we postulate possible mechanisms which may have contributed to their development, including inadvertent breach of the peritoneum and leakage of gas around the diaphragmatic herniae or tracking of gas retroperitoneally. The case alerts us to the possibility of this complication occurring in patients undergoing videoscopic herniorrhaphy.
Rae, Ian D
At the beginning of the twentieth century, an anaesthetist could choose between nitrous oxide, chloroform, and ether (diethyl ether) for the induction of painrelieving unconsciousness. By the end of century, the choice was between a small number of fluorinated aliphatic ethers such as Enflurane, Desflurane, and Sevoflurane, and (in some jurisdictions) the rare gas, xenon. Between these endpoints researchers had identified a surprisingly broad range of hydrocarbons, noble gases, organohalogens, and aliphatic ethers that possessed anaesthetic properties. None was entirely satisfactory, but clinicians at various times and in various places employed substances in each of these categories. Behind the search for new anaesthetic gases was a theory of action (Meyer- Overton theory) that was known to be inadequate, but as no alternative was strong enough to displace it the search continued on purely empirical grounds, while lip-service was paid to the theory. By the time a theory couched in more modern terms was proposed, a suite of modern anaesthetic gases was in place, and there have been no attempts to use that theory to drive a new search.
Kretzschmar, Moritz; Schilling, Thomas; Vogt, Andreas; Rothen, Hans Ulrich; Borges, João Batista; Hachenberg, Thomas; Larsson, Anders; Baumgardner, James E; Hedenstierna, Göran
The mismatching of alveolar ventilation and perfusion (VA/Q) is the major determinant of impaired gas exchange. The gold standard for measuring VA/Q distributions is based on measurements of the elimination and retention of infused inert gases. Conventional multiple inert gas elimination technique (MIGET) uses gas chromatography (GC) to measure the inert gas partial pressures, which requires tonometry of blood samples with a gas that can then be injected into the chromatograph. The method is laborious and requires meticulous care. A new technique based on micropore membrane inlet mass spectrometry (MMIMS) facilitates the handling of blood and gas samples and provides nearly real-time analysis. In this study we compared MIGET by GC and MMIMS in 10 piglets: 1) 3 with healthy lungs; 2) 4 with oleic acid injury; and 3) 3 with isolated left lower lobe ventilation. The different protocols ensured a large range of normal and abnormal VA/Q distributions. Eight inert gases (SF6, krypton, ethane, cyclopropane, desflurane, enflurane, diethyl ether, and acetone) were infused; six of these gases were measured with MMIMS, and six were measured with GC. We found close agreement of retention and excretion of the gases and the constructed VA/Q distributions between GC and MMIMS, and predicted PaO2 from both methods compared well with measured PaO2. VA/Q by GC produced more widely dispersed modes than MMIMS, explained in part by differences in the algorithms used to calculate VA/Q distributions. In conclusion, MMIMS enables faster measurement of VA/Q, is less demanding than GC, and produces comparable results.
Philip, J H
Screen-based simulation can improve patient care by giving novices and experienced clinicians insight into drug behaviour. Gas Man(®) is a screen-based simulation program that depicts pictorially and graphically the anaesthetic gas and vapour tension from the vaporizer to the site of action, namely the brain and spinal cord. The gases and vapours depicted are desflurane, enflurane, ether, halothane, isoflurane, nitrogen, nitrous oxide, sevoflurane, and xenon. Multiple agents can be administered simultaneously or individually and the results shown on an overlay graph. Practice exercises provide in-depth knowledge of the subject matter. Experienced clinicians can simulate anaesthesia occurrences and practices for application to their clinical practice, and publish the results to benefit others to improve patient care. Published studies using this screen-based simulation have led to a number of findings, as follows: changing from isoflurane to desflurane toward the end of anaesthesia does not accelerate recovery in humans; vital capacity induction can produce loss of consciousness in 45 s; simulated context-sensitive decrement times explain recovery profiles; hyperventilation does not dramatically speed emergence; high fresh gas flow is wasteful; fresh gas flow and not the vaporizer setting should be reduced during intubation; re-anaesthetization can occur with severe hypoventilation after extubation; and in re-anaesthetization, the anaesthetic redistributes from skeletal muscle. Researchers using screen-based simulations can study fewer subjects to reach valid conclusions that impact clinical care. © The Author 2015. Published by Oxford University Press on behalf of the British Journal of Anaesthesia. All rights reserved. For Permissions, please email: firstname.lastname@example.org.
Valentim, A M; Guedes, S R; Pereira, A M; Antunes, L M
Several questions have been raised in recent years about the euthanasia of laboratory rodents. Euthanasia using inhaled agents is considered to be a suitable aesthetic method for use with a large number of animals simultaneously. Nevertheless, its aversive potential has been criticized in terms of animal welfare. The data available regarding the use of carbon dioxide (CO2), inhaled anaesthetics (such as isoflurane, sevoflurane, halothane and enflurane), as well as carbon monoxide and inert gases are discussed throughout this review. Euthanasia of fetuses and neonates is also addressed. A table listing currently available information to ease access to data regarding euthanasia techniques using gaseous agents in laboratory rodents was compiled. Regarding better animal welfare, there is currently insufficient evidence to advocate banning or replacing CO2 in the euthanasia of rodents; however, there are hints that alternative gases are more humane. The exposure to a volatile anaesthetic gas before loss of consciousness has been proposed by some scientific studies to minimize distress; however, the impact of such a measure is not clear. Areas of inconsistency within the euthanasia literature have been highlighted recently and stem from insufficient knowledge, especially regarding the advantages of the administration of isoflurane or sevoflurane over CO2, or other methods, before loss of consciousness. Alternative methods to minimize distress may include the development of techniques aimed at inducing death in the home cage of animals. Scientific outcomes have to be considered before choosing the most suitable euthanasia method to obtain the best results and accomplish the 3Rs (replacement, reduction and refinement). © The Author(s) 2015.
Carlos Vilaplana Santaló
Full Text Available La hipertermia maligna es un desorden hipermetabólico de los músculos esqueléticos, caracterizado por hipercalcemia intracelular y consumo rápido de adenosín trifosfato; esta condición se desencadena por la exposición a 1 o más agentes anestésicos precipitantes incluidos halotano, enflurano, isoflurano, desflurano, sevoflurano y el succinilcolina. Los síntomas de esta afección pueden presentarse en el quirófano o en la Unidad de Cuidados Posanestésicos y se caracteriza por aparición súbita de taquicardia, taquipnea, hipertensión, hipercapnia, hipertermia, acidosis y rigidez musculoesquelética. El dantroleno atenúa la elevación del calcio intracelular y puede ser administrado de forma profiláctica o inmediatamente que se sospeche el diagnóstico. Con el objetivo de conocer las bases fisiopatológicas de este síndrome y las pautas de tratamiento más empleadas se realizó una exhaustiva revisión bibliográficaMalignant hyperthermia is a hypermetabolic disorder of the skeletal muscles, characterized by intracellular hypercalcemia and rapid consumption of adenosine triphosphate. This condition appears as a result of the exposure to 1 or more precipitating anesthetic agents, including halothane, enflurane, isoflurane, desflurane, sevoflurane and succinylcholine. The symptoms of this affection may be present in the operating room or in the Unit of Postanesthetic Care and it is characterized by the sudden appearance of thachycardia, tachypnea, hypertensiion, hypercapnia, hyperthermia, acidosis and muscoloskeletal rigidity. Dantrolene attenuates the elevation of intracellular calcium and may be prophylactically administered or as soon as the diagnosis is suspected. In order to know the physiopathological basis of this syndrome and the most used treatment patterns, an exhaustive bibliographic review was made
Shelton, Keith L
Because the toxicity of many inhalants precludes evaluation in humans, drug discrimination, an animal model of subjective effects, can be used to gain insights on their poorly understood abuse-related effects. The purpose of the present study was to train a prototypic inhalant that has known abuse liability, 1,1,1-trichloroethane (TCE), as a discriminative stimulus in mice, and compare it to other classes of inhalants. Eight B6SJLF1/J mice were trained to discriminate 10 min of exposure to 12,000 ppm inhaled TCE vapor from air and seven mice were trained to discriminate 4,000 ppm TCE from air. Tests were then conducted to characterize the discriminative stimulus of TCE and to compare it to representative aromatic and chlorinated hydrocarbon vapors, volatile halogenated anesthetics as well as an odorant compound. Only the 12,000 ppm TCE versus the air discrimination group exhibited sufficient discrimination accuracy for substitution testing. TCE vapor concentration- and exposure time-dependently substituted for the 12,000 ppm TCE vapor training stimulus. Full substitution was produced by trichloroethylene, toluene, enflurane, and sevoflurane. Varying degrees of partial substitution were produced by the other volatile test compounds. The odorant, 2-butanol, did not produce any substitution for TCE. The discriminative stimulus effects of TCE are shared fully or partially by chlorinated and aromatic hydrocarbons as well as by halogenated volatile anesthetics. However, these compounds can be differentiated from TCE both quantitatively and qualitatively. It appears that the degree of similarity is not solely a function of chemical classification but may also be dependent upon the neurochemical effects of the individual compounds.
Duenges, Bastian; Vogt, Andreas; Bodenstein, Marc; Wang, Hemei; Böhme, Stefan; Röhrig, Bernd; Baumgardner, James E; Markstaller, Klaus
The multiple inert gas elimination technique was developed to measure shunt and the ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung (V(A)'/Q') distributions. Micropore membrane inlet mass spectrometry (MMIMS), instead of gas chromatography, has been introduced for inert gas measurement and shunt determination in a rabbit lung model. However, agreement with a frequently used and accepted method for quantifying deficits in arterial oxygenation has not been established. We compared MMIMS-derived shunt (M-S) as a fraction of total cardiac output (CO) with Riley shunt (R-S) derived from the R-S formula in a porcine lung injury model. To allow a broad variance of atelectasis and therefore shunt fraction, 8 sham animals did not receive lavage, and 8 animals were treated by lung lavages with 30 mL/kg warmed lactated Ringer's solution as follows: 2 animals were lavaged once, 5 animals twice, and 1 animal 3 times. Variables were recorded at baseline and twice after induction of lung injury (T1 and T2). Retention data of sulfur hexafluoride, krypton, desflurane, enflurane, diethyl ether, and acetone were analyzed by MMIMS, and M-S was derived using a known algorithm for the multiple inert gas elimination technique. Standard formulas were used for the calculation of R-S. Forty-four pairs of M-S and R-S were recorded. M-S ranged from 0.1% to 35.4% and R-S from 3.7% to 62.1%. M-S showed a correlation with R-S described by linear regression: M-S = -4.26 + 0.59 x R-S (r(2) = 0.83). M-S was on average lower than R-S (mean = -15.0% CO, sd = 6.5% CO, and median = -15.1), with lower and upper limits of agreement of -28.0% and -2.0%, respectively. The lower and upper limits of the 95% confidence intervals were -17.0 and -13.1 (P < 0.001, Student's t-test). Shunt derived from MMIMS inert gas retention data correlated well with R-S during breathing of oxygen. Shunt as derived by MMIMS was generally less than R-S.
Full Text Available Perkembangan dan kemajuan teknologi serta ilmu pengetahuan telah mendorong pelaksanaan pelayanan kesehatan yang lebih efektif dan lebih ekonomis dibanding dengan cara yang lazim dikerjakan. Telah dilakukan penelitian terhadap 32 pasien operasi laparotomi ginekologis yang dibagi menjadi dua kelompok. Kelompok Tramadol (n=16 diberikan tramadol 2 mg/kgBB (pengenceran akuabides sampai 10 mL lewat jalur infus selama satu menit, sedangkan pada kelompok Fentanil (n=16 diberikan fentanil 2 µg/kgBB dengan cara yang sama. Lima menit kemudian diberikan propofol 2 mg/kgBB, atrakurium 0,5 mg/kgBB, enfluran 2 volume %, N2O:O2=2 L/menit:2 L/menit. Setelah tiga menit dilakukan laringoskopi intubasi. Pasien diventilasi kendali dengan mode ventilator IPPV. Operasi dilaksanakan bila kedalaman anestesi tercapai berdasar atas skor PRST (P=systolic arterial pressure, R=heart rate, S=sweat, dan T=tears 2 sampai dengan 4. Analgetik pertolongan 50 µg fentanil diberikan bila skor PRST lebih dari 4. Analgetik postoperatif 30 mg ketorolak dan antimuntah 10 mg metoklopramid diberikan saat jahit kulit. Pencatatan tekanan darah, laju nadi, saturasi O2, dan skor PRST dilakukan sebagai berikut: T0 = penderita tiba di kamar operasi, T1= preintubasi, T2= satu menit setelah intubasi, T3= satu menit setelah insisi, T4 dan seterusnya diukur tiap 15 menit sampai selesai operasi. Pasien diekstubasi setelah pernapasan adekuat. Skala sedasi dan muntah dinilai setiap 15 menit setelah ekstubasi selama dua jam. Dari hasil penelitian didapatkan skor PRST mulai T1 sampai T12 secara statistis tidak berbeda bermakna antara kelompok tramadol dan fentanil (p>0,05. Kedua kelompok mengalami peningkatan skor PRST satu menit setelah intubasi. Skor PRST dipertahankan antara 0 sampai 2. Pada kelompok tramadol dan fentanil masing-masing satu orang mendapatkan analgetik pertolongan fentanil 50 µg karena skor PRST 5. Tidak ditemukan perbedaan skala sedasi dan muntah antara dua kelompok perlakuan
P. R. Dudov
Full Text Available Objective: to study the safety and clinical and economic efficiency of early activation of children operated on under extracorporeal circulation (EC. Subjects and methods. Sixty-eight children aged 4—14 years (8.6±0.4 years operated on under EC for congenital heart diseases (CHD were examined. In accordance with the time of switching to spontaneous respiration and tracheal extubation, 2 groups were identified: 1 those who received postoperative artificial ventilation (AV for 2.9±0.2 hours (a study group; 2 those who had AV for 8.7±0.7 hours (a control group. Both groups did not differ in age, cardiac diseases, their severity, anthropometric characteristics, EC duration, aortic ligation time, and abnormality pattern. In the study group, anesthesia was maintained with fentanyl (5.3±0.1 ^g/kg/hr, diazepam (0.15±0.01 mg/kg/hr, and inhaled ftorotan or enflurane. Diazepam was discontinued in the postperfusion period. The control group received fentanyl (7.6±0.4 ^Bg/kg/hr, diazepam (0.3±0.02 mg/kg/hr, droperidol (0.4±0.04 mg/kg/hr, and/or sodium oxybutyrate (81±5 mg/kg/hr. Myoplegia was provided by pancuronium or pipecuronium that was continuously infused until EC was completed in Group 1 and intermittently injected until the end of surgery in Group 2. Results. There were no indications for tracheal reintubation in both groups of patients. The early postoperative period was uncomplicated in 97.2% of the children in the study group and in 28.1% in the control group (p<0.05. The incidence of pulmonary complications was 2.8 and 46.9%, respectively (p<0.05. In the children from Groups 1 and 2, the duration of a resuscita-tive period was 44.2±1.7 and 77.3±4.9 hours, respectively (p<0.05, and that of the whole postoperative period was 12.6±0.3 and 18.0±1.1 days (p<0.05. In the study group, the total final expenditures, including the cost of anesthesia and treatment for postoperative complications, decreased by 127.5% as compared to the control
Manuseio de grave diminuição de hemoglobina em paciente jovem, testemunha de Jeová, submetido à proctocolectomia total: relato de caso Manoseo de grave disminución de hemoglobina en paciente joven, testigo de Jehová, sometido a la proctocolectomia total: relato de caso Extreme intraoperative hemodilution in Jehovah’s witness patient submitted total proctocolectomy: case report
Luiz Eduardo Imbelloni
family history of adenomatous polyposis. The disease was manifested at eight years of age, characterized by bleeding. At 13 years of age he was submitted to total colectomy. At 17 years of age he was submitted to total proctocolectomy. Patient was prepared with erythropoietin, folic acid, infusion of iron and vitamin B12. Red blood cell count revealed He = 4,200,000/mm³, hemoglobin = 10.5 g/dL, hematocrit = 37% platelets = 273,000/mm³ and normal prothrombin time. Patient was continuously monitored with NIBP, pulse oximetry, capnography and ECG. Anesthesia was induced with propofol, sufentanil, pancuronium and enflurane in closed system. Patient received 7,000 mL lactated Ringer’s and 150 mL of 20% human albumin. Total diuresis was 2,900 mL. Surgery lasted 10 hours and 30 minutes. Patient was referred to the ICU with 20% hematocrit, 2,300,000/mm³ red cells, 4,2 g/dL hemoglobin and was maintained with propofol and atracurium. Next day evaluation revealed 18% hematocrit, 2,050,000/mm³ red cells and 4 g/dL hemoglobin. Patient was extubated 18 hours after surgery and was referred to the ward. Patient started eating four days after surgery and was discharged the 10th postoperative day. Thirty days later patient presented 35% hematocrit, 4,000,000/mm³ red cells and 9.5 g/dL hemoglobin. Six months later he returned for ileostomy closing. Patient was submitted to 12 surgeries without a single blood transfusion. CONCLUSIONS: A good planning of the whole team (clinician, surgeon, anesthesiologist, intensive care staff allows us to perform surgical procedures associated to major blood losses without administering blood.