艾司氯胺酮对内毒素性急性肺损伤大鼠肺组织细胞焦亡的影响

目的:评价艾司氯胺酮对内毒素性急性肺损伤大鼠肺组织细胞焦亡的影响。方法:SPF级健康成年雄性SD大鼠30只,体重200～220 g,8周龄。采用随机数字表法分为3组( n＝10)：对照组(C组)、内毒素性急性肺损伤组(ALI组)和艾司氯胺酮组(E组)。采用腹腔注射LPS 10 mg/kg的方法制备大鼠内毒素...     

艾司氯胺酮用于乳腺癌改良根治术老年患者术后自控静脉镇痛的效果

目的:评价艾司氯胺酮用于乳腺癌改良根治术老年患者术后自控静脉镇痛的效果。方法:择期全麻下行乳腺癌改良根治术女性患者90例,年龄65~78岁,体重46~75 kg,ASA分级Ⅱ或Ⅲ级,采用随机数字表法分为2组( n＝45)：艾司氯胺酮PCIA组(E组)和舒芬太尼PCIA组(S组)。靶控输注丙泊酚、静脉注射顺苯...     

艾司氯胺酮PCIA对剖宫产术孕产妇产后抑郁症的影响

目的:评价艾司氯胺酮PCIA对剖宫产术孕产妇产后抑郁症的影响。方法:选择择期椎管内麻醉下行剖宫产术的孕产妇300例,年龄25～35岁,BMI≤35 kg/m 2,ASA分级Ⅰ或Ⅱ级,依照随机数字表法分为2组( n＝150)：对照组(C组)和艾司氯胺酮(E组)。术毕行PCIA,C组药物配方：枸橼酸...     

艾司氯胺酮复合麻醉对肺癌根治术患者术后心理痛苦的影响

目的:评价艾司氯胺酮复合麻醉对肺癌根治术患者术后心理痛苦的影响。方法:2019年12月至2020年11月在本院行肺癌根治术患者121例,性别不限,年龄18~75岁,BMI 18.5~24.9 kg/m 2,ASA分级Ⅰ~Ⅲ级。采用随机数字表法分为2组：对照组(C组, n＝60)和艾司氯胺酮复合麻...     

艾司氯胺酮对小鼠脑缺血再灌注损伤的影响及其与线粒体应激的关系

目的评价艾司氯胺酮对小鼠脑缺血再灌注损伤的影响及其与线粒体应激的关系。方法实验Ⅰ SPF级雄性C57BL/6小鼠18只, 8～12周龄, 体质量28～30 g, 采用随机数字表法分为3组(n=6):假手术组(S组)、脑缺血再灌注组(IR组)和艾司氯胺酮+脑缺血再灌注组(E+IR组)。采用大脑中动脉栓塞1 h, 再灌注24 h的方法制备脑缺血再灌注损伤模型;E组造模前20 min腹腔注射艾司氯胺酮10 mg/kg。采用Zea Longa评分及平衡木实验(Feeney评分)评估小鼠神经功能;TTC染色法测定脑梗死体积。实验Ⅱ将原代皮层神经元采用随机数字表法分为3组(n=42):对照组(C组)、氧糖剥夺/复氧复糖组(OGD/R组)和艾司氯胺酮+OGD/R组(E+OGD/R组)。采用氧糖剥夺1 h, 复氧复糖24 h的方法制备OGD/R模型。E+OGD/R组加入25 μmol/L艾司氯胺酮处理40 min后制备模型。采用CCK-8法检测神经元活力, 透射电镜下观察神经元超微结构, 检测ROS、谷胱甘肽过氧化物酶(GSH-px)和MDA的水平, JC-1试剂盒检测线粒体膜电位, TUNEL染色法...     

小剂量艾司氯胺酮对患儿扁桃体腺样体切除术全麻苏醒期躁动的影响

目的 探讨全麻诱导前预防性应用小剂量艾司氯胺酮对患儿扁桃体腺样体切除术全麻苏醒期躁动(EA)的影响.方法 选择2021年1—3月择期行扁桃体腺样体切除术的患儿97例,男48例,女49例,年龄3～12岁,体重15～50 kg,ASAⅠ或Ⅱ级.采用随机数字表法将患儿分为两组:艾司氯胺酮组(S组,n=49)和对照组(C组,n...     

艾司氯胺酮对丙泊酚麻醉致发育期大鼠远期认知功能障碍的影响及PI3K/Akt信号通路在其中的作用

目的评价艾司氯胺酮对丙泊酚麻醉致发育期大鼠远期认知功能障碍的影响及磷脂酰肌醇3-激酶(PI3K)/丝氨酸-苏氨酸激酶(Akt)信号通路在其中的作用。方法清洁级健康SD大鼠48只, 雌雄不拘, 7日龄, 体质量10～15 g, 采用随机数字表法分为4组(n=12):脂肪乳剂组(C组)、丙泊酚组(P组)、艾司氯胺酮+丙泊酚组(EP组)和PI3K抑制剂LY294002+艾司氯胺酮+丙泊酚组(LYEP组)。C组腹腔注射中/长链脂肪乳注射液100 mg/kg;P组腹腔注射丙泊酚50 mg/kg, 待大鼠翻正反射恢复后(40～60 min), 再追加丙泊酚50 mg/kg;EP组腹腔注射艾司氯胺酮10 mg/kg, 随后再给予丙泊酚, 方法同P组;LYEP组经侧脑室注射LY294002 25 μg, 30 min后腹腔注射艾司氯胺酮10 mg/kg, 随后给予丙泊酚, 方法同P组。于苏醒后2 h时, 每组随机处死6只大鼠, 采用HE染色法检测海马神经元病理学结果, 采用Western blot法检测海马组织Akt、磷酸化Akt(p-Akt)、Bax和cleaved caspase-3的表达。剩余6...     

脑创伤患者急性期皮质醇分泌的变化

目的 探讨脑创伤患者急性期皮质醇(COR)分泌的变化.方法 创伤后2～24 h入院的脑创伤患者75例,根据Glasgow昏迷评分分为轻度脑创伤组(TBI1组,n=30)、中度脑创伤组(TBI2组,n=12)和重度脑创伤组(TBI3组,n=33),13例同期住院的颈椎病或颅骨骨瘤患者为对照组(C组).于入院后1 d时采集静脉血样,测定血清总COR、促肾上腺皮质激素和皮质醇结合球蛋白的浓度,计算游离COR浓度及游离COR指数.记录高血COR的发生情况.结果 与C组比较,TBI1组、TBI2组和TBI3组血清总COR、促肾上腺皮质激素、游离COR的浓度及游离COR指数均升高(P＜0.05),且TBI2组和TBI3组高于TBI1组(P＜0.05);四组间皮质醇结合球蛋白浓度比较差异无统计学意义(P＞0.05).TBI1组、TBI2组和TBI3组高血COR发生率高于C组,且TBI3组高于TBI1组和TBI2组(P＜0.05).结论 脑创伤患者急性期COR分泌升高,COR分泌水平与创伤程度有关.

Abstract：

Objective To investigate the changes in cortisol (COR) secretion in the acute phase of traumatic brain injury (TBI) .Method Seventy-five patients admitted to the hospital at 2-24 h after TBI were divided into 3 groups based on the Glasgow Coma Scale score: mild TBI group (group TBI1, n = 30), moderate TBI group (group TBI2, n = 12) and severe TBI group (TBI3, n = 33). Thirteen patients with cervical spondylosis or osteoma of the skull (admitted to the hospital at the same period) were regarded as control group (group C). Venous blood samples were taken on the first day after admission to measure the serum concentrations of total COR, adrenocorticotropin (ACTH) and corticosteroid-binding globulin (CBG). Free COR concentrations and free COR index were calculated. High blood COR was recorded. Result Compared with group C, the serum concentrations of total COR and ACTH, free COR levels and free COR index were significantly increased in TBI1, TBI2 and TBI3groups (P ＜ 0.05). The parameters mentioned above were significantly higher in TBI2 and TBI3 groups than in TBI1 group ( P ＜0.05). There was no significant difference in serum CBG concentrations among the four groups.The incidence of high blood COR was significantly higher in TBI1, TBI2 and TBI3 groups than in C group, and in TBI3 group thanin TBI1 and TBI2 groups (P ＜0.05). Conclusion COR secretion is increased in the acute phase of TBI and the level of COR secretion is related to the severity of brain damage.     

艾司氯胺酮对术后认知功能障碍老龄大鼠海马神经元程序性坏死的影响

目的评价艾司氯胺酮对术后认知功能障碍老龄大鼠海马神经元程序性坏死的影响。方法 SPF级健康雄性SD大鼠120只, 月龄22月, 体质量550～600 g, 采用随机数字表法分为4组(n=30):对照组(C组)、术后认知功能障碍组(P组)、术后认知功能障碍+艾司氯胺酮组(PE组)和艾司氯胺酮组(CE组)。P组和PE组大鼠在七氟烷麻醉下接受剖腹探查术, 术毕分别腹腔注射艾司氯胺酮10 mg/kg和等量0.9%氯化钠注射液, 1次/d, 连续6 d。CE组和C组不给予麻醉手术处理, 分别腹腔注射艾司氯胺酮10 mg/kg和等量0.9%氯化钠注射液, 1次/d, 连续6 d。4组大鼠于术后7 d时行Morris水迷宫实验, 记录逃避潜伏期、穿越原平台位置次数和原平台所在象限停留时间;水迷宫实验结束后, 处死大鼠取海马组织, 采用流式细胞术测定海马神经元程序性坏死率和胞浆Ca2+浓度;采用Western blot法检测混合谱系激酶结构域样蛋白(MLKL)、磷酸化MLKL(p-MLKL)、受体相互作用蛋白3(RIPK3)、磷酸化RIPK3(p-RIPK3)、RIPK1和磷酸化RIPK1(p-RIP...     

艾司氯胺酮对大鼠脓毒症急性肾损伤的影响及自噬在其中的作用

目的评价艾司氯胺酮对大鼠脓毒症急性肾损伤(AKI)的影响及自噬在其中的作用。方法 SPF级健康雄性成年SD大鼠40只, 体重200～240 g, 采用随机数字表法分为5组(n=8):对照组(Con组)、艾司氯胺酮组(Con+Ket组)、脓毒症组(LPS组)、脓毒症+艾司氯胺酮组(LPS+Ket组)和脓毒症+艾司氯胺酮+3-甲基腺嘌呤组(LPS+Ket+3MA组)。采用腹腔注射LPS制备脓毒症大鼠AKI模型, Con组腹腔注射生理盐水10 ml/kg;Con+Ket组腹腔注射生理盐水10 ml/kg, 30 min后尾静脉注射艾司氯胺酮10 mg/kg;LPS组腹腔注射LPS 10 mg/kg;LPS+Ket组腹腔注射LPS 10 mg/kg, 30 min后尾静脉注射艾司氯胺酮10 mg/kg;LPS+Ket+3MA组腹腔注射LPS 10 mg/kg, 30 min后尾静脉注射艾司氯胺酮10 mg/kg和3-MA 15 mg/kg。腹腔注射LPS后24 h时麻醉大鼠, 随后处死取肾组织, 观察病理学结果, 采用ELISA法测定核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)、凋亡相关斑...     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.