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1.
Baumert JH Hecker KE Hein M Reyle-Hahn SM Horn NA Rossaint R 《British journal of anaesthesia》2005,94(6):727-732
Background. It was hypothesized that xenon would stabilize meanarterial pressure (MAP) in haemorrhagic shock, recovery, andvolume resuscitation, because a higher MAP has been observedwith xenon, when compared with isoflurane anaesthesia. The responsesto haemorrhage and subsequent volume replacement were thereforecompared between xenon and isoflurane anaesthesia, in pigs. Methods. Pigs were randomized to anaesthesia with xenon 0.55MAC (group Xe, n=9) or isoflurane 0.55 MAC (group Iso, n=9),each with remifentanil 0.5 µg kg1 min1.MAP, heart rate, cardiac output (CO), and left ventricular fractionalarea change (FAC) were collected at control (1), after haemorrhage(20 ml kg1) (2), after 10 min of recovery (3), aftervolume replacement (4), and 30 min later (5). Data were analysedby two-way repeated measures ANOVA. Results. Blood loss decreased MAP (Xe: 103 [21] to 53 [24] mmHg; Iso: 92 [18] to 55 [14] mm Hg) and CO (Xe: 4.1 [0.8] to2.6 [0.5] litre min1; Iso: 5.1 [1.1] to 3.8 [1.2] litremin1), in spite of significant tachycardia. MAP and COrecovered to about 75% of control, and subsequent volume replacementcompletely reversed symptoms in both groups, but increased FAConly with xenon. Conclusion. Haemodynamic response to acute haemorrhage appearedfaster with xenon/remifentanil than with isoflurane/remifentanilanaesthesia. In particular MAP decrease and short-term recoverywere more marked with xenon (P<0.02). In the xenon group,volume replacement increased FAC compared with control and isoflurane(P<0.02). 相似文献
2.
Picker O Schindler AW Schwarte LA Preckel B Schlack W Scheeren TW Thämer V 《British journal of anaesthesia》2002,88(4):546-554
Background. This study was designed to examine whether the couplingbetween oxygen consumption (V·O2) and cardiac output(CO) is maintained during xenon anaesthesia. Methods. We studied the relationship between V·O2 (indirectcalorimetry) and CO (ultrasound flowmetry) by adding xenon toisoflurane anaesthesia in five chronically instrumented dogs.Different mixtures of xenon (70% and 50%) and isoflurane (01.4%)were compared with isoflurane alone (1.4% and 2.8%). In addition,the autonomic nervous system was blocked (using hexamethonium)to study its influence on V·O2 and CO during xenon anaesthesia. Results. Mean (SEM) V·O2 increased from 3.4 (0.1) ml kg1 min1during 1.4% isoflurane to 3.7 (0.2) and 4.0 (0.1) ml kg1 min1after addition of 70% and 50% xenon, respectively (P<0.05),whereas CO and arterial pressure remained essentially unchanged.In contrast, 2.8% isoflurane reduced both, V·O2 [from3.4 (0.1) to 3.1 (0.1) ml kg1 min1]and CO [from 96 (5) to 70 (3) ml kg1 min1](P<0.05). V·O2 and CO correlated closely during isofluraneanaesthesia alone and also in the presence of xenon (r2=0.94and 0.97, respectively), but the regression lines relating COto V·O2 differed significantly between conditions, withthe line in the presence of xenon showing a 0.30.6 ml kg1 min1greater V·O2 for any given CO. Following ganglionic blockade,50% and 70% xenon elicited a similar increase in V·O2,while CO and blood pressure were unchanged. Conclusions. Metabolic regulation of blood flow is maintainedduring xenon anaesthesia, but cardiovascular stability is accompaniedby increased V·O2. The increase in V·O2 is independentof the autonomic nervous system and is probably caused by directstimulation of the cellular metabolic rate. Br J Anaesth 2002; 88: 54654 相似文献
3.
Propofol-alfentanil vs propofol-remifentanil for posterior spinal fusion including wake-up test 总被引:1,自引:0,他引:1
Background. Wake-up test can be used during posterior spinalfusion (PSF) to ensure that spinal function remains intact.This study aims at assessing the characteristics of the wake-uptest during propofolalfentanil (PA) vs propofolremifentanil(PR) infusions for PSF surgery. Methods. Sixty patients with scoliosis and candidates for PSFsurgery were randomly allocated in either alfentanil (PA) orremifentanil (PR) group. After an i.v. bolus of alfentanil 30µg kg1 in the PA group or remifentanil 1 µgkg1 in the PR group, anaesthesia was induced with thiopentaland atracurium. During maintenance, opioid infusion consistedof alfentanil 1 µg kg1 min1 or remifentanil0.2 µg kg1 min1, in the PA group and thePR group, respectively. All patients received propofol 50 µgkg1 min1. Atracurium was given to maintain therequired surgical relaxation. At the surgeon's request, allinfusions were discontinued. Patients were asked to move theirhands and feet. Time from anaesthetic discontinuation to spontaneousventilation (T1), and from then until movement of the handsand feet (T2), and its quality were recorded. Results. The average T1 and T2 were significantly shorter inthe PR group [3.6 (2.5) and 4.1 (2) min] than the PA group [6.1(4) and 7.5 (4.5) min]. Quality of wake-up test, however, didnot show significant difference between the two groups studied. Conclusion. Wake-up test can be conducted faster with remifentanilcompared with alfentanil infusion during PSF surgery. 相似文献
4.
Effect of remifentanil infusion rate on stress response to the pre-bypass phase of paediatric cardiac surgery 总被引:11,自引:1,他引:10
Background. Opioids are used routinely to eliminate the stressresponse in the pre-bypass phase of paediatric cardiac surgery.Remifentanil is a unique opioid allowing a rapidly titratableeffect. No data are available regarding a suitable remifentanildose regimen for obtunding stress and cardiovascular responsesto such surgery. Methods. We recruited 49 infants and children under 5 yr oldwho were randomized to receive one of four remifentanil infusionrates (0.25, 1.0, 2.5, or 5.0 µg kg1 min1).Blood samples were obtained at induction, pre-surgery, 5 minafter opening the chest, and immediately pre-bypass. Whole bloodglucose was measured at all time points while cortisol and neuropeptideY (NPY) were measured in the first and last samples. Heart rateand arterial pressure were also recorded. Results. There was a significant increase in whole blood glucose5 min after opening the chest and pre-bypass (P=0.009, P=0.002)in patients receiving remifentanil 0.25 µg kg1min1, but not in those receiving higher doses. Increasedremifentanil dosage was associated with reduced plasma cortisolduring surgery (P<0.001). Baseline NPY showed considerablevariation and there was no association between pre-bypass NPYand remifentanil dose. There was a significantly higher heartrate at the pre-bypass stage of surgery in the remifentanil0.25 µg kg1 min1 group compared with higherdoses (P=0.0006). Four out of five neonates with complex cardiacconditions showed severe bradycardia associated with remifentanil. Conclusions. In infants and children under 5 yr, remifentanilinfusions of 1.0 µg kg1 min1 and greatercan suppress the glucose increase and tachycardia associatedwith the pre-bypass phase of cardiac surgery, while 0.25 µgkg1 min1 does not. Remifentanil should be usedwith caution in neonates with complex congenital heart disease. Br J Anaesth 2004; 92: 18794 相似文献
5.
Dahaba AA Perelman SI Moskowitz DM Bennett HL Shander A Oettl K Reibnegger G Metzler H 《British journal of anaesthesia》2006,97(4):482-488
Background. Acute normovolaemic haemodilution (ANH) is an effectivestrategy for avoiding or reducing allogeneic blood transfusion.We aimed to study its effect on the pharmacological profileof rocuronium. Methods. In two study centres, 28 patients undergoing majorsurgery with ANH were matched with 28 control patients. In thedoseresponse groups, using the mechanomyograph, neuromuscularblock of six consecutive incremental doses of rocuronium 50µg kg1, followed by 300 µg kg1, wasevaluated. In the pharmacokinetics groups, serial arterial bloodsamples were withdrawn for rocuronium assay after a single doseof rocuronium 600 µg kg1. Results. ANH resulted in a shift to the left of rocuronium doseresponsecurve. Rocuronium effective dose95 (ED95) was 26% lower (P<0.05)in the ANH group [283.4 (92.0) µg kg1] comparedwith the control group [383.5 (127.3) µg kg1].Times from administration of last incremental dose until 25%of first response of train-of-four (TOF) recovery (Dur25) and0.8 TOF ratio recovery (Dur0.8) were 28% longer in the ANH group[39.9 (8.4), 66.7 (14.2) min] compared with the control group[31.1 (6.6), 52.1 (15.8) min] (P<0.01, P<0.05), respectively.Volume of distribution was higher (P<0.01), central clearancewas lower (P<0.05) and terminal elimination half-life waslonger (P<0.0001) in the ANH group [234.97 (47.11) ml kg1,4.70 (0.94) ml kg1 min1, 77.29 (12.25) min] comparedwith the control group [181.22 (35.73) ml kg1, 5.71 (1.29)ml kg1 min1, 56.86 (10.05) min, respectively]. Conclusion. ANH resulted in prolongation of rocuronium time-courseof action, thus careful monitoring of neuromuscular block isrecommended in patients who undergo ANH. 相似文献
6.
Hackner C Detsch O Schneider G Jelen-Esselborn S Kochs E 《British journal of anaesthesia》2003,91(4):580-582
Background. We compared recovery from high-dose propofol/low-doseremifentanil (propofol-pronounced) compared withhigh-dose remifentanil/low-dose propofol (remifentanil-pronounced)anaesthesia. Methods. Adult patients having panendoscopy, microlaryngoscopy,or tonsillectomy were randomly assigned to receive either propofol-pronounced(propofol 100 µg kg1 min1; remifentanil0.15 µg kg1 min1) or remifentanil-pronounced(propofol 50 µg kg1 min1; remifentanil 0.45µg kg1 min1) anaesthesia. In both groups,the procedure was started with remifentanil 0.4 µg kg1,propofol 2 mg kg1, and mivacurium 0.2 mg kg1.Cardiovascular measurements and EEG bispectral index (BIS) wererecorded. To maintain comparable anaesthetic depth, additionalpropofol (0.5 mg kg1) was given if BIS values were greaterthan 55 and remifentanil (0.4 µg kg1) if heartrate or arterial pressure was greater than 110% of pre-anaestheticvalues. Results. Patient and surgical characteristics, cardiovascularmeasurements, and BIS values were similar in both groups. Therewere no differences in recovery times between the groups (timeto extubation: 12.7 (4.5) vs 12.0 (3.6) min, readiness for transferto the recovery ward: 14.4 (4.4) vs. 13.7 (3.6) min, mean (SD)). Conclusions. In patients having short painful surgery, lesspropofol does not give faster recovery as long as the same anaestheticlevel (as indicated by BIS and clinical signs) is maintainedby more remifentanil. However, recovery times were less variablefollowing remifentanil-pronounced anaesthesia suggesting a morepredictable recovery. Br J Anaesth 2003; 91: 5802 相似文献
7.
Comparison of propofol/remifentanil and sevoflurane/remifentanil for maintenance of anaesthesia for elective intracranial surgery 总被引:13,自引:0,他引:13
Background. Propofol and sevoflurane are suitable agents formaintenance of anaesthesia during neurosurgical procedures.We have prospectively compared these agents in combination withthe short-acting opioid, remifentanil. Methods. Fifty unpremedicated patients undergoing elective craniotomyreceived remifentanil 1 µg kg1 followed by an infusioncommencing at 0.5 µg kg1 min1 reducing to0.25 µg kg1 min1 after craniotomy. Anaesthesiawas induced with propofol, and maintained with either a target-controlledinfusion of propofol, minimum target 2 µg ml1 orsevoflurane, initial concentration 2%ET. Episodes of mean arterialpressure (MAP) more than 100 mm Hg or less than 60 mm Hg formore than 1 min were defined as hypertensive or hypotensiveevents, respectively. A surgical assessment of operating conditionsand times to spontaneous respiration, extubation, obey commandsand eye opening were recorded. Drug acquisition costs were calculated. Results. Twenty-four and twenty-six patients were assigned topropofol (Group P) and sevoflurane anaesthesia (Group S), respectively.The number of hypertensive events was comparable, whilst morehypotensive events were observed in Group S than in Group P(P=0.053, chi-squared test). As rescue therapy, more labetolol[45 (33) vs 76 (58) mg, P=0.073] and ephedrine [4.80 (2.21)vs 9.78 (5.59) mg, P=0.020] were used in Group S. Between groupdifferences in recovery times were small and clinically unimportant.The combined hourly acquisition costs of hypnotic, analgesic,and vasoactive drugs appeared to be lower in patients maintainedwith sevoflurane than with propofol. Conclusion. Propofol/remifentanil and sevoflurane/remifentanilboth provided satisfactory anaesthesia for intracranial surgery. 相似文献
8.
Pitsiu M Wilmer A Bodenham A Breen D Bach V Bonde J Kessler P Albrecht S Fisher G Kirkham A 《British journal of anaesthesia》2004,92(4):493-503
Background. The pharmacokinetics of remifentanil, an opioidanalgesic metabolized by non-specific esterases, and its principalmetabolite, remifentanil acid (RA), which is excreted via thekidneys, were assessed as part of an open-label safety studyin intensive care unit (ICU) patients with varying degrees ofrenal impairment. Methods. Forty adult ICU patients with normal/mildly impairedrenal function (creatinine clearance [CLcr] 62.9 (SD) 14.5 mlmin1; n=10) or moderate/severe renal impairment (CLcr14.7 (15.7) ml min1; n=30) were included. Remifentanilwas infused for up to 72 h, at a starting rate of 69µg kg1 h1 titrated to achieve a target sedationlevel, with additional propofol (0.5 mg kg1 h1)if required. Intensive arterial sampling was performed for upto 72 h after infusion. Pharmacokinetic parameters obtainedby simultaneous modelling of remifentanil and RA data were statisticallycompared between the two groups. Results. Remifentanil pharmacokinetics were not significantlyaffected by renal status. RA clearance in the moderate/severegroup was reduced to about 25% that of the normal/mild group(41 (29) vs 176 (49) ml kg1 h1, P<0.0001).Metabolic ratio, a predictor of the ratio of RA to remifentanilconcentrations at steady state, was approximately eight-foldhigher in the moderate/severe group relative to the normal/mildgroup (116 (110) vs 15 (4), P<0.0001). Maximum RA levelsapproached 700 ng ml1 in the moderate/severe group. Conclusions. Although RA accumulates in patients with moderate/severerenal impairment, pharmacokinetic modelling predicts that RAconcentrations during a 9 µg kg1 h1 remifentanilinfusion for up to 15 days would not exceed those reported inthe present study, for which no associated prolongation of µ-opioideffects was observed. Br J Anaesth 2004; 92: 493503 相似文献
9.
Glycopyrrolate during sevoflurane-remifentanil-based anaesthesia for cardiac catheterization of children with congenital heart disease 总被引:1,自引:0,他引:1
Reyntjens K Foubert L De Wolf D Vanlerberghe G Mortier E 《British journal of anaesthesia》2005,95(5):680-684
Background. Remifentanil is recommended for use in procedureswith painful intraoperative stimuli but minimal postoperativepain. However, bradycardia and hypotension are known side-effects.We evaluated haemodynamic effects of i.v. glycopyrrolate duringremifentanilsevoflurane anaesthesia for cardiac catheterizationof children with congenital heart disease. Methods. Forty-five children undergoing general anaesthesiawith remifentanil and sevoflurane were randomly allocated toreceive either saline, glycopyrrolate 6 µg kg1or glycopyrrolate 12 µg kg1. After induction ofanaesthesia with sevoflurane, i.v. placebo or glycopyrrolatewas administered. An infusion of remifentanil at the rate of0.15 µg kg1min1 was started, sevofluranecontinued at 0.6 MAC and cisatracurium 0.2 mg kg1 wasgiven. Heart rate (HR) and non-invasive arterial pressures weremonitored and noted every minute for the first 10 min and thenevery 2.5 min for subsequent maximum of 45 min. Results. Baseline HR [mean (SD)] of 117 (20) beats min1decreased significantly from 12.5 min onwards after startingthe remifentanil infusion in the control group [106 (18) at12.5 min and 99 (16) beats min1 at 45 min]. In the groupsreceiving glycopyrrolate, no significant decrease in HR wasnoticed. Glycopyrrolate at 12 µg kg1 induced tachycardiabetween 5 and 9 min after administration. Systolic and diastolicarterial pressures decreased gradually, but there were no significantdifferences in the pressures between groups. Conclusion. I.V. glycopyrrolate 6 µg kg1 preventsbradycardia during general anaesthesia with remifentanil andsevoflurane for cardiac catheterization in children with congenitalheart disease. Administering 12 µg kg1 of glycopyrrolatetemporarily induces tachycardia and offers no additional advantage. 相似文献
10.
Schwarte LA Picker O Höhne C Fournell A Scheeren TW 《British journal of anaesthesia》2004,93(4):552-559
Background. The effects of thoracic epidural anaesthesia (TEA)on gastric mucosal microvascular haemoglobin oxygenation (µHbO2)are unclear. At the splanchnic level, reduction of sympathetictone may promote vasodilation and increase µHbO2. However,these splanchnic effects are counteracted by systemic effectsof TEA (e.g., decreased cardiac output (CO) and mean arterialpressure (MAP)), thus making the net effect on µHbO2 difficultto predict. In this respect, effects of TEA on µHbO2 maydiffer between physiological and compromised circulatory conditions,and additionally may depend on adequate fluid resuscitation.Furthermore, TEA may alter the relationship between regionalµHbO2 and systemic oxygen-transport (DO2). Methods. Chronically instrumented dogs (flow probes for CO measurement)were anaesthetized, their lungs ventilated and randomly receivedTEA with lidocaine (n=6) or epidural saline (controls, n=6).Animals were studied under physiological and compromised circulatoryconditions (PEEP 10 cm H2O), both with and without fluid resuscitation.We measured gastric mucosal µHbO2 by reflectance spectrophotometry,systemic DO2, and systemic haemodynamics (CO, MAP). Results. Under physiological conditions, TEA preserved µHbO2(47 (3)% and 49 (5)%, mean (SEM)) despite significantly decreasingDO2 (11.3 (0.8) to 10.0 (0.7) ml kg1 min1) andMAP (66 (2) to 59 (3) mm Hg). However, during compromised circulatoryconditions, TEA aggravated the reduction in µHbO2 (to32 (1)%), DO2 (to 6.7 (0.8) ml kg1 min1) and MAP(to 52 (4) mm Hg), compared with controls. During TEA, fluidresuscitation completely restored these variables. TEA preservedthe correlation between µHbO2 and DO2, compared with controls. Conclusions. TEA maintains µHbO2 under physiological conditions,but aggravates the reduction of µHbO2 induced by cardiocirculatorydepression, thereby preserving the relationship between gastricmucosal and systemic oxygenation.
Presented in part at the German Anaesthesia Congress 2003 (April912, Munich, Germany) and the European Society of IntensiveCare Congress 2003 (October 58, Amsterdam, The Netherlands). 相似文献
11.
Background. Lung resistance increases after induction of anaesthesia.We hypothesized that prophylactic bronchodilation with i.v.carperitide before tracheal intubation would decrease airwayresistance and increase lung compliance after placement of thetracheal tube in both smokers and nonsmokers. Methods. Ninety-seven adults aged between 24 and 59 yr wererandomized to receive i.v. normal saline (0.9% saline) (control)or carperitide, 0.2 µg kg1 min1 throughoutthe study. The 97 patients included smokers and nonsmokers.Thus the patients were allocated to one of the four groups:smokers who received normal saline (n=21), nonsmokers who receivednormal saline (n=27), smokers who received carperitide (n=19)or nonsmokers who received carperitide (n=30). Thirty minutesafter starting normal saline or carperitide infusion, we administeredthiamylal 5 mg kg1 and fentanyl 5 µg kg1to induce general anaesthesia and vecuronium 0.3 mg kg1for muscle relaxation. Continuous infusion of thiamylal 15 mgkg1 h1 followed anaesthetic induction. Mean airwayresistance (Rawm), expiratory airway resistance (Rawe) and dynamiclung compliance (Cdyn) were determined 4, 8, 12 and 16 min aftertracheal intubation and compared between the four groups. Results. At 4 min after intubation, Rawm and Rawe were higherand Cdyn lower in smokers than in nonsmokers in the controlgroup. Rawm and Rawe were lower and Cdyn higher in smokers inthe carperitide group than in smokers in the control group.Rawm and Rawe were lower in nonsmokers in the carperitide groupthan in nonsmokers in the control group. Conclusions. Marked bronchoconstriction occurred in the controlgroups (smokers and nonsmokers) 4 min after tracheal intubation.Prophylactic treatment with carperitide before induction ofanaesthesia and tracheal intubation was advantageous, particularlyin smokers. 相似文献
12.
Effect of 1 or 2 MAC isoflurane with or without ketanserin on cerebral blood flow autoregulation in man 总被引:2,自引:0,他引:2
OLSEN K. S.; HENRIKSEN L.; OWEN-FALKENBERG A.; DIGE-PETERSEN H.; ROSENoRN J.; CHRAEMMER-JoRGENSEN B. 《British journal of anaesthesia》1994,72(1):66-71
We have studied the effect of 1 or 2 MAC isoflurane with orwithout ketanserin on cerebral blood flow (CBF), cerebral oxygenmetabolism (CMRO2) and CBF autoregulation in 20 adult patientsundergoing lumbar disc surgery. Ten patients received ketanserinand 10 isotonic saline. CBF measurements were started after1 h of infusion of saline or ketanserin. The patients were anaesthetizedwith thiopentone 5 mg kg1 followed by isoflurane. During1 MAC of isoflurane, baseline values were recorded and thenCBF autoregulation was examined (mean arterial pressure increasedby about 30% with angiotensin). The sequence was repeated with2 MAC of isoflurane. CBF was measured by the i.v. xenon-133technique. CMRo2 was calculated as the product of CBF and thecerebral arterio-venous oxygen content difference. Ketanserinhad no effect on CBF, CMRo2 or CBF autoregulation during isofluraneanaesthesia, therefore all patients were pooled for evaluationof the effect of isoflurane. Increasing isoflurane anaesthesiafrom 1 to 2 MAC increased mean CBF from 41 to 49 ml /100 g min1(P<: 0.01) and decreased mean CMRo2 from 1.5 to 1.1 ml/100g min1 (P < 0.001) and thus abolished the couplingbetween flow and metabolism. The CBF autoregulation test indicatedthat autoregulation was disrupted at 2 MAC, but not during 1MAC isoflurane anaesthesia. (Br. J. Anaesth. 1994; 72: 6671) 相似文献
13.
Background. To determine the response to mivacurium, we prospectivelystudied onset time and complete spontaneous recovery from mivacurium-inducedneuromuscular block in patients with Duchenne muscular dystrophy(DMD). Methods. Twelve boys with DMD, age 514 yr, seven of themwheelchair-bound, ASA IIIII, and 12 age- and sex-matchedcontrols (ASA I) were enrolled in the study. Anaesthesia wasinduced with fentanyl 23 µg kg1 and propofol34 mg kg1 titrated to effect, and maintained bycontinuous i.v. infusion of propofol 812 mg kg1and remifentanil as required. The lungs were ventilated withoxygen in air. Neuromuscular transmission was assessed by acceleromyographyusing train-of-four (TOF) stimulation every 15 s. After baselinereadings, a single dose of mivacurium 0.2 mg kg1 wasgiven. The following variables were recorded: (i) lag time;(ii) onset time; (iii) peak effect; (iv) recovery of first twitchfrom the TOF response to 10, 25 and 90% (T10, T25, T90) relativeto baseline; (v) recovery index (time between 25 and 75% recoveryof first twitch); and (vi) recovery time (time between 25% recoveryof first twitch and recovery of TOF ratio to 90%). For comparisonbetween the groups the MannWhitney U-test was applied. Results. There were no differences between the groups in lagtime, onset time and peak effect. However, all recorded recoveryindices were significantly (P<0.05) prolonged in the DMDgroup. The median (range) for time points T10, T25 and T90 inthe DMD and control group was 12.0 (816) vs 8.4 (515)min, 14.1 (920) vs 10.5 (717) min and 26.9 (1540)vs 15.9 (1223) min, respectively. The recovery indexand recovery time were similarly prolonged in the DMD group. Conclusions. These results support the assumption that mivacurium-inducedneuromuscular block is prolonged in patients with DMD.
This study was presented at the Annual Meeting of the AmericanSociety of Anaesthesiologists, Las Vegas, October 2004.
These authors contributed equally to this work. 相似文献
14.
Background. The Alaris AEP monitorTM (Alaris, UK, version 1.4)is the first commercially available auditory evoked potential(AEP) monitor designed to estimate the depth of anaesthesia.It generates an Alaris AEP index (AAI), whichis a dimensionless number scaled from 100 (awake) to 0. Thisstudy was designed to compare AAI and BISTM (Aspect, USA, versionXP) values at different levels of anaesthesia. Methods. Adult female patients were premedicated with diazepam0.15 mg kg1 orally on the morning of surgery. Electrodesfor BIS and Alaris AEP monitoring and a headphone to give auditorystimuli were applied as recommended by the manufacturers. Anaesthesiawas induced with remifentanil (0.4 µg kg1 min1)and a propofol target-controlled infusion (DiprifusorTM TCI,AstraZeneca, Germany) to obtain a predicted concentration ofinitially 3.5 µg ml1. After loss of consciousnessthe patients were given 0.5 mg kg1 of atracurium. Aftertracheal intubation, remifentanil was given at 0.2 µgkg1 min1 and the propofol infusion was adjustedto obtain BIS target values of 30, 40, 50, and 60. AAI and BISvalues were recorded and matched with the predicted propofoleffect-site concentrations. Prediction probability was calculatedfor consciousness vs unconsciousness. Values are mean (SD). Results. Fifty female patients, 53 (15), range 1878 yr,ASA I or II were studied. Mean values before induction of anaesthesiawere 95 (4), range 9982 for BIS and 85 (12), range 9955for AAI. With loss of eyelash reflex both values were significantlyreduced to 64 (13), range 8339 for BIS (P<0.05) and61 (22), range 9915 for AAI (P<0.05). The predictionprobability PK for consciousness vs unconsciousness (i.e. lossof eyelash reflex) was better for BIS (PK=0.99) than for AAI(PK=0.79). At a BIS of 30, 40, 50, and 60 the correspondingAAI values were 15 (6), 20 (8), 28 (11), and 40 (16), and thesewere significantly different. Conclusions. During propofol-remifentanil anaesthesia a decreaseof the depth of anaesthesia as indicated by BIS monitoring isaccompanied by corresponding effects shown by the AAI. However,wide variation in the awake values and considerable overlapof AAI values between consciousness and unconsciousness, suggestsfurther improvement of the AAI system is required. Br J Anaesth 2003; 91: 33640 相似文献
15.
Remifentanil or propofol for sedation during carotid endarterectomy under cervical plexus block 总被引:7,自引:0,他引:7
Krenn H Deusch E Jellinek H Oczenski W Fitzgerald RD 《British journal of anaesthesia》2002,89(4):637-640
Background. During carotid endarterectomy under regional anaesthesia,patients often require medication to control haemodynamic instabilityand to provide sedation and analgesia. Propofol and remifentanilare used for this purpose. However, the benefits, side-effects,and optimal dose of these drugs in such patients are unclear. Methods. Sixty patients were included in a prospective, randomized,single blinded study. All patients received a deep cervicalplexus block with 30 ml ropivacaine 0.75% and were randomizedto receive either remifentanil 3 µg kg1 h1or propofol 1 mg kg1 h1. The infusions were startedafter performing the regional block and were stopped at theend of surgery. Arterial pressure, ECG, ventilatory rate, andPaCO2 were measured continuously and recorded at predeterminedtimes. Twenty-four hours after surgery, patient comfort, andsatisfaction were also evaluated. Results. In three patients, the infusion of remifentanil hadto be stopped because of severe respiratory depression or bradycardia.No significant differences were found between the two groupsin haemodynamic variables or sedative effects, but there wasa significantly greater decrease in ventilatory frequency andincrease in PaCO2 in the remifentanil group. The patientssubjective impressions and pain control were excellent in bothgroups. Conclusion. As a result of the higher incidence of adverse respiratoryeffects with remifentanil and similar sedative effects, propofolis preferable for sedation during cervical plexus block in elderlypatients with comorbid disease at the dosage used. Br J Anaesth 2002; 89: 63740 相似文献
16.
Schubert HM Lorenz IH Zschiegner F Kremser C Hohlrieder M Biebl M Kolbitsch C Moser PL 《British journal of anaesthesia》2004,92(4):532-535
Background. Surgical pain typically combines superficial anddeep pain. We wished to generate pain that resembled surgicalpain, reliably and reproducibly, in volunteers. Methods. We constructed a computer-controlled pneumatic deviceto apply pressure to the anterior tibia. The reproducibilityof the pain was tested by rating the pressure that caused painrated 45 on a visual analogue scale (VAS) on days 0,7, and 24 in 10 volunteers. The effect of remifentanil (0.025,0.05, 0.075, and 0.1 µg kg1 min1) on paintolerance in another set of volunteers (n=11) was used as anindirect measure of the reliability of pain production. Results. The pressure needed (0.7 (0.3) to 0.9 (0.4) atm (mean(SD)) to induce pain rated 45 (VAS) did not vary, showinglong-term reproducibility of the method. When pressure was appliedto cause increasing pain in volunteers (n=11) 0.05 µgkg1 min1 remifentanil increased pain toleranceby 50%. An approximate doubling of the dose (0.1 µg kg1min1) increased pain tolerance significantly more. Thelinear logarithmic dose-effect relationship shows that the devicecauses pain reliably, and this can be reduced with opioid treatment. Conclusion. This pneumatic device can apply pain reliably andreproducibly. Br J Anaesth 2004; 92: 5325 相似文献
17.
Background. In this study we aimed to clarify the role of endothelinin arterial pressure regulation during anaesthesia with increasingconcentrations of sevoflurane (13 MAC) and compare itwith those of vasopressin and angiotensin. Methods. After an awake control period, on different days, sixdogs underwent each of the following four interventions: sevofluraneanaesthesia alone (13 MAC), sevoflurane after block ofeither endothelin receptors using tezosentan (3 mg kg1followed by 3 mg kg1 h1), vasopressinV1a receptors using [d(CH2)5Tyr(Me2)]AVP (40 µg kg--1)or angiotensin receptors using losartan (6 mg kg1 h1).Plasma concentrations of endothelin, big endothelin, vasopressinand renin were measured. Effects of sevoflurane in the presenceand absence of the respective receptor block were analysed andcompared using analysis of variance for repeated measures (ANOVAfollowed by Fishers PLSD (protected least significantdifference) (P<0.05)). Results. Mean arterial pressure decreased in a dose-dependentmanner with sevoflurane during all interventions. At 1 MAC,this decrease was greatest during angiotensin receptor block(mean (SEM), 41 (3) mm Hg), intermediate duringvasopressin and endothelin receptor block (31 (4) and30 (2) mm Hg respectively), and least during sevofluranealone (24 (3) mm Hg). The course of systemic vascularresistance mirrored the course of arterial pressure, while cardiacoutput did not differ between groups. Plasma concentrationsof endothelin, big endothelin and renin did not change duringany intervention, whereas vasopressin concentration increasedfrom 相似文献
18.
Lorenz IH Kolbitsch C Hinteregger M Bauer P Spiegel M Luger TJ Schmidauer C Streif W Pfeiffer KP Benzer A 《British journal of anaesthesia》2003,90(3):296-299
Background. Cerebral blood flow is affected by painful stimuli,and analgesic agents may alter the response of cerebral bloodflow to pain. We set out to quantify the effects of remifentaniland nitrous oxide on blood flow changes caused by experimentalpain. Methods. We simulated surgical pain in 10 conscious volunteersusing increasing mechanical pressure to the tibia. We measuredchanges in cerebral blood flow velocity in the middle cerebralartery (CBFVMCA) caused by the pain, using transcranial Dopplersonography. We gave increasing doses of remifentanil (0.025,0.05 and 0.1 µg kg1 min1)or nitrous oxide [20%, 35% and 50% end-tidal concentration (FE'N2O)]and compared these effects on blood flow changes. Results. Nitrous oxide increased CBFVMCA only when given at50% FE'N2O. Remifentanil did not affect CBFVMCA. Pain increasedCBFVMCA. Both agents attenuated this pain-induced change inCBFVMCA with the exception of nitrous oxide at 20% FE'N2O. Conclusions. Inhalation of nitrous oxide or adminstration ofremifentanil attenuated pain-induced changes in CBFVMCA. Br J Anaesth 2003: 90: 2969 相似文献
19.
There is evidence that halothane inhibits nitric oxide synthasein vitro, but the effect of intravenous anaesthetic agents isless clear. This study was undertaken to compare the rate ofexhaled nitric oxide production (VNO) in spontaneously breathinghorses anaesthetized with halothane or an intravenous regimen.Seven adult horses were studied twice in random order. Afterpremedication with romifidine 100 µg kg1,anaesthesia was induced with ketamine 2.2 mg kg1and maintained with halothane in oxygen (HA) or by an intravenousinfusion of ketamine, guaiphenesin and romifidine (IV). Inhaledand exhaled nitric oxide (NO) concentrations, respiratory minuteventilation (VE), pulmonary artery pressure (PPA), fractionalinspired oxygen concentration (FIO2), end-tidal carbon dioxideconcentration (E'CO2), cardiac output (Q) and partial pressuresof oxygen and carbon dioxide in arterial blood (PaO2, PaCO2)were measured. Exhaled nitric oxide production rate was significantlylower (40 min, P<0.01; 60 min, P<0.02) duringHA [40 min, 1.4 (SD 1.4) pmol l1 kg1 min1;60 min, 0.7 (0.7) pmol l1 kg1 min1]than during IV [40 min, 9.3 (9.9) pmol l1 kg1min1; 60 min, 12.5 (13.3) pmol l1 kg1min1). Mean pulmonary artery pressure was significantlyhigher (40 min, P<0.01; 60 min, P<0.001) during HA[40 min, 5.9 (1.1) kPa; 60 min, 5.9 (0.9) kPa] comparedwith IV (40 min, 4.4 (0.4) kPa; 60 min, 4.4 (0.5) kPa].NO is reduced in the exhalate of horses anaesthetized with halothanecompared with an intravenous regimen. It is suggested that increasedmean pulmonary artery pressure during halothane anaesthesiamay be linked to the differences in NO production. Br J Anaesth 2001; 86: 12730 相似文献
20.
Kabara S Hirota K Yoshioka H Kudo T Ishihara H Matsuki A 《British journal of anaesthesia》2003,91(3):379-384
Background. Thiopental sometimes causes bronchospasm duringinduction of anaesthesia. In addition, we have reported previouslythat thiopental produced transient bronchospasm, which was blockedby atropine pretreatment, and worsened histamine-induced bronchoconstrictionin dogs. Previous in vitro reports suggest that synthesis ofcontractile cyclooxygenase products, such as thromboxane A2,may be involved in the mechanism of bronchospasm. However, thein vivo spastic effects have not been defined comprehensively. Methods. Twenty-seven mongrel dogs were anaesthetized with pentobarbital.Bronchoconstriction was elicited with methacholine (0.5 µg kg1+5.0µg kg1 min1; Mch group, n=7) orserotonin (10 µg kg1+1 mg kg1 h1;5HT group, n=20), and assessed as percentage changes in bronchialcross-sectional area (BCA, basal=100%) using a bronchoscope.In the 5HT group, dogs were subdivided into four groups of fiveeach: S-5HT, I-5HT, 5HT-S and 5HT-A. In the S-5HT and I-5HTgroups, 30 min before serotonin infusion dogs were given salineand indomethacin respectively at 5 mg kg1 i.v. Inall groups, 30 min after bronchoconstrictor infusion started,dogs were given thiopental at doses between 0 (saline) and 20mg kg1. In the 5HT-S and 5HT-A groups, dogs weregiven saline or atropine 0.2 mg kg1 i.v. 5 min afterthiopental 20 mg kg1. Results. Methacholine and serotonin reduced BCA by about 50and 40% respectively. Thiopental 20 mg kg1 increasedand decreased BCA by about 20 and 10% in the Mch and 5HT groupsrespectively. Indomethacin and atropine did not attenuate thepotentiation of serotonin bronchoconstriction produced by thiopental. Conclusion. The present study indicates that thiopental mayattenuate or worsen bronchoconstriction induced by muscarinicor serotonin receptor stimulation, respectively. The synthesisof contractile cyclooxygenase products and cholinergic stimulationmay not be involved in the contractile effect of thiopentalon serotonin bronchoconstriction. Br J Anaesth 2003; 91: 37984 相似文献