异丙酚和异氟醚对非体外循环搭桥术患者围术期细胞因子的影响

目的:研究异丙酚和异氟醚对非体外循环搭桥术患者围术期炎性与抗炎性细胞因子平衡的影响。方法:择期非体外循环搭桥患者50例,随机分为2组。异丙酚组微量泵输入剂量为4～6mg·kg-·1h-1,异氟醚组吸入浓度为1%～1.5%。检测诱导前、打开心包、旁路血管开放30min,术后2h、24h血清白细胞介素6(IL-6)、白细胞介素10(IL-10)和肿瘤坏死因子α(TNF-α)的浓度。结果:2组患者旁路血管开放后IL-6浓度较术前升高(P<0.01),术后2h达高峰;术后2h异氟醚组高于异丙酚组(P<0.05)。IL-10浓度变化趋势与IL-6相似,旁路血管开放后、术后2h和24h异丙酚组高于异氟醚组(P<0.05)。2组患者TNF-α水平均无显著变化。结论:异丙酚麻醉促进IL-10的产生,抑制IL-6的产生,控制术中应激反应异丙酚优于异氟醚。     

离体模式下地氟醚、异氟醚和氟烷通过氧合器应用的药代动力学研究

目的研究在离体模式下地氟醚、异氟醚和氟烷通过氧合器应用的药代动力学。方法选择成人型膜式氧合器，预充生理盐水2000ml，连接动静脉端形成环路。将预先配制在钢瓶内的2．4％地氟醚、0．46％异氟醚及0．308％氟烷混合气体输送至氧合器，气体流量3Umin，泵流量4Umin，温度30℃。在摄入及排出的0、1、2、4、8、16、32min采集氧合器入气口、排气口及动脉端样本，测定吸入麻醉药分压。结果在摄入阶段及排出阶段，动脉端溶液中三种吸入麻醉药分压迅速上升或下降，用药后8min时，三种药物的动脉端样本分压与吸入气分压之比(Pa／Pi)均达50％以上，停药后8min动脉端样本分压与动脉端样本分压峰值之比(Pa／Pa0)均降至10％以下。三种药物之间在同一时间点Pa／Pi及Pa／17aO均有显著性差异(P＜0．05)。各吸入麻醉药动脉端样本与氧合器排气口中分压之间呈线性相关关系(r=0．99)。结论(1)Bentley膜式氧合器具有快速转运吸入麻醉药的性能；(2)地氟醚、异氟醚及氟烷通过氧合器应用后摄取和排出速率随着药物的水／气分配系数的增高而减慢；(3)通过监测氧合器排气口中吸入麻醉药分压可以快速、准确地估计液相中吸入麻醉药分压。     

Cardiac arrest after isoflurane anaesthesia in a patient with Duchenne''s muscular dystrophy

An 8-year-old boy known to have Duchenne's muscular dystrophy suffered a cardiac arrest 10 minutes after he regained consciousness after isoflurane anaesthesia for an orchidopexy procedure. Resuscitation was successful 2 hours after the start of external cardiac compression and after correction of hyperkalaemia and the administration of dantrolene. He later developed myoglobinuria elevated creatine kinase and a metabolic and respiratory acidosis. He demonstrated a delayed increase in rectal temperature.     

Rapid tolerance against focal cerebral ischemia induced by isoflurane anesthesia is attenuated by adenosine A1 receptor antagonist in rats

The brief anesthesia with isoflurane induces rapid tolerance against focal cerebral ischemia in rats and aden-osine A1 receptor antagonist, DPCPX, attenuates the beneficial effect of isoflurane preconditioning.     

Isoflurane for removal of chest drains after cardiac surgery

Thirty-five patients who had undergone uncomplicated cardiac surgery were randomly allocated to receive either Entonox or isoflurane 0.25% in Entonox as inhalational analgesia for the removal of their two chest drains. The gases were presented premixed in high-pressure cylinders and were self-administered by means of a demand valve. The removal of the second drain was more painful than the first but that pain was better controlled by isoflurane 0.25% in Entonox than by Entonox alone.     

Different effects of halothane, isoflurane and sevoflurane on sarcoplasmic reticulum of vascular smooth muscle in dog mesenteric artery

Background: The direct effect of halothane on vascular smooth muscle is mediated in part via its effects on the sarcoplasmic reticulum (SR). Little information is available concerning the effects of other volatile anesthetics including isoflurane and sevoflurane, whose vascular effects differ from those of halothane. The aim of the present study was to compare the effects of halothane, isoflurane and sevoflurane on the SR by testing the contraction induced by caffeine in vascular smooth muscle. Methods: Rings without endothelium from isolated canine mesenteric artery were mounted in physiological saline solution (PSS) for isometric tension recording. After complete depletion of Ca²⁺ from the SR by adding 35 mM caffeine, the rings were exposed to normal Ca²⁺ containing PSS (Ca²⁺ loading), to Ca²⁺-free PSS for 10 min, and then to 15 mM caffeine to induce contraction. Anesthetics were administered during Ca²⁺ loading, the Ca²⁺-free phase and simultaneously with caffeine administration. Results: Halothane (0.5-2%) attenuated the caffeine-induced contraction of canine mesenteric artery when administered during Ca²⁺ loading in the SR (P<0.001), whereas isoflurane and sevoflurane (1–4%) failed to affect the contraction. When given simultaneously with caffeine, halothane (1–2%) potentiated the caffeine-induced contraction (P<0.05), but isoflurane and sevoflurane had no effect. When given before caffeine administration, halothane (0.5-2%), isoflurane (24%) and sevoflurane (4%) all potentiated the caffeine-induced contraction (P<0.05). Conclusion: It has been shown that halothane not only potentiates caffeine- induced Ca²⁺ release from the SR, but also induces contraction by releasing Ca²⁺ from the SR. We conclude that halothane decreases Ca²⁺ accumulation in the SR while exerting facilitative and additive effects on caffeine-induced Ca²⁺ release from the SR when applied before caffeine administration and simultaneously with caffeine, respectively, whereas isoflurane and sevoflurane lack both the ability to decrease Ca²⁺ accumulation and an additive effect on caffeine-induced Ca²⁺ release from the SR, but are able to facilitate Ca²⁺ release by caffeine.     

不同麻醉方法对28例胃癌手术患者红细胞醛糖还原酶及血浆一氧化氮的影响

目的:观察不同麻醉方法对胃癌手术患者红细胞醛糖还原酶(AR)活性及血浆一氧化氮(NO)浓度的影响。方法:28例胃癌手术患者随机分为两组,组1吸入1.5～2.0最小肺泡吸入有效浓度(MAC)的异氟醚,组2为0.5～1.0MAC异氟醚复合硬膜外麻醉。分别于麻醉前30min、手术90min、术后60min、术后1天和术后2天5个时间点抽取静脉血,测定血糖浓度、红细胞AR活性及血浆NO浓度。结果:与麻醉前值相比,组1病人血糖浓度于手术90min、术后60min、术后1天明显升高(P<0.05或P<0.01);术后1天红细胞AR活性明显升高(P<0.05),同时血浆NO浓度显著下降(P<0.05)。组2病人血糖浓度于手术90min、术后60min显著升高(P<0.01);红细胞AR活性及血浆NO浓度,虽有与组1病人相似的变化趋势,但与麻醉前值相比,各时间点无明显变化。术后1天组1病人红细胞AR活性明显高于组2(P<0.05),而血浆NO浓度则相反(P<0.05),两组间血糖无明显差异。结论:胃癌手术病人在应激高血糖状态下,红细胞多元醇途径被激活的同时血浆NO合成受抑制。全麻联合硬膜外阻滞能较好抑制这一改变。     

A Pilot Study: Defibrillation Thresholds in Dogs are Similar with Isoflurane, Halothane, and Pentobarbital

The objective of this pilot study was to determine if three common anesthetic drugs have differing effects on the measurement of defibrillation thresholds (DFT) in dogs. The drugs compared were pentobarbital, isoflurane, and halothane. We used six dogs, which were surgically instrumented, in a chronic study design. Each dog had two internal defibrillation patches placed on its heart, which were used to deliver the defibrillation energy. DFT was determined while each dog was anesthetized under each of the listed drugs in a crossover design. This pilot study suggests that differences in DFT due to the anesthetic drugs is not significant in studies with low numbers of animals (halothane 14.5 ± 1.0, isoflurane 14.2 ± 1.0, pentobarbital 12.8 ± 1.0;P = NS; mean ± SE). Tbe variation in DFT between individual animals is much larger than the difference in DFT due to the drugs.     

The onset of ablation of the evoked adductor pollicis muscle twitch in children: a clinical perspective

The time to loss of the adductor pollicis muscle response to ulnar nerve stimulation at 1 Hz (twitch) after succinylcholine, 1.5 mg.kg-1 intravenously (IV), or vecuronium, 0.1 mg.kg-1 (IV), administration was assessed visually in 134 children, age 2-13 yr, during clinically determined, deep halothane, enflurane and isoflurane anaesthesia. The overall time to twitch ablation and duration of succinylcholine's action is in agreement with published times obtained under controlled experimental conditions; the onset time following vecuronium is comparable to those observed during a similar anaesthetic background measured under controlled experimental conditions. Twitch ablation after succinylcholine was achieved in half the time needed following vecuronium regardless of anaesthetic agent. Succinylcholine's and vecuronium's onset time as well as succinylcholine's duration is adequately assessed by the outlined, simple clinical means. The choice of inhalation agent does not affect the time to visible twitch ablation in a clinically relevant manner; nor does it make an appreciable difference, in clinical terms, in succinylcholine's duration of action.