Economy in the use of muscle relaxants Vecuronium after pancuronium

Vecuronium is an intermediate duration, non-depolarising muscle relaxant. When used during prolonged procedures, it may be given by intermittent injection, by continuous infusion or by a single very large dose at the start of anaesthesia. It may also be used to maintain relaxation after the initial use of a long-acting agent, such as pancuronium. This study demonstrates that the effect of a dose of vecuronium used in this fashion is increased when interaction with pancuronium takes place. The clinical and theoretical implications of this observation are discussed.     

Neuromuscular transmission and its blockade

The role of two recently introduced muscle relaxants--atracurium and vecuronium--in contemporary anaesthetic practice is assessed. Recent advances in the physiology of neuromuscular transmission, particularly the roles of calcium and calmodulin, are reviewed, and new ideas concerning the reversal and monitoring of neuromuscular blockade are discussed.     

A comparison of the neuromuscular blocking effects and reversibility of cisatracurium and atracurium

The neuromuscular blocking effects and the reversibility of cisatracurium 0.1 or 0.15 mgkg⁻¹ were compared with those of atracurium 0.5 mgkg⁻¹ during anaesthesia with propofol, nitrous oxide and isoflurane. Neuromuscular block was monitored using train-of-four stimulation while recording the mechanomyographic response of the adductor pollicis muscle. The block was either allowed to recover spontaneously or was antagonised with neostigmine 50 μgkg⁻¹ at 10% or 25% recovery of the first twitch of the train-of-four. The median times to maximum block were 2.7, 2.2 and 1.5 min following cisatracurium 0.1 and 0.15 mgkg⁻¹ and atracurium 0.5 mgkg⁻¹, respectively. After cisatracurium 0.1 mgkg⁻¹ had been given, the median time to recovery of the train-of-four ratio to 0.8 ('adequate recovery') was 74 min during spontaneous recovery, 48 min after reversal with neostigmine when the first twitch of the train-of-four had returned to 10% of control and 50 min after reversal when the first twitch of the train-of-four had returned to 25% of control. These times for cisatracurium 0.15 mgkg⁻¹ and atracurium 0.5 mgkg⁻¹ were 90, 66 and 57 min and 75, 56 and 54 min, respectively. Administration of neostigmine significantly shortened the time to adequate recovery for both drugs but there were no significant differences in the case of either neuromuscular blocking drug between the groups of patients given neostigmine at 10 or 25% recovery of the first twitch of the train-of-four.     

Spontaneous movements, local reactions and pain on injection of rocuronium. A comparison between female and male patients

BACKGROUND: We investigated the incidence of withdrawal, local reactions and pain on injection of rocuronium in 120 adult ASA I-II patients undergoing general anaesthesia (group A: 60 male patients, group B: 60 female patients). METHODS: After induction of anaesthesia with propofol and remifentanil, rocuronium 0.6 mg kg(-1) was injected in a separate intravenous cannula on the opposite arm. The patient's response to the injection of rocuronium was graded using a four-point scale. The appearance of local signs (i.e. erythema, venous sequelae) on the arm where rocuronium had been injected was recorded at the end of the injection as well as 1 h and 24 h after recovery from anaesthesia. Moreover, patients were asked 24 h after recovery from anaesthesia whether they had recall of pain or movements in this arm during induction of anaesthesia. RESULTS: In 26 of the 120 patients (22%) included, withdrawal reactions after injection of rocuronium were observed. Of these 26 patients, 16 (13%) had severe movements. The overall incidence of withdrawal reactions after rocuronium as well as the incidence of severe reactions was significantly higher in female patients compared to male patients (overall incidence: 18 females (30%) vs. 8 males (13%), P<0.05; severe reaction: 13 females (22%) vs. 3 males (5%), P<0.05). No local reactions were observed and no patient remembered any pain or movements during induction of anaesthesia. CONCLUSION: The incidence and the degree of withdrawal reactions in response to the injection of rocuronium were significantly higher in women than in men. This was not associated with adverse clinical consequences for the patient's outcome.     

Dose-response studies of atracurium, vecuronium and pancuronium in the elderly

Dose-response curves were constructed for atracurium, vecuronium and pancuronium in elderly subjects in order to assess potency of these relaxants. The results were compared to data previously obtained for adult subjects using the same method. A single-dose method of potency determination was used in both studies. The results indicate no significant difference in the potency of these relaxants between elderly and adult subjects; the ED95S were 249 and 226 micrograms/kg for atracurium, 43.1 and 39.6 micrograms/kg for vecuronium and 65.9 and 60 micrograms/kg for pancuronium respectively in the elderly and the adults.     

The chronotropic effect of acetylcholine in the presence of vecuronium and atracurium A study in the isolated perfused rabbit heart

The bradycardia produced by 1 microgram acetylcholine in the isolated perfused rabbit heart, in the presence of vecuronium and atracurium, was studied and compared with control. Vecuronium at a concentration of 2.5 micrograms/litre and atracurium 6 micrograms/litre did not enhance the negative chronotropic effect of acetylcholine. Atracurium produced a statistically significant inhibition of the negative chronotropic effect of acetylcholine.     

CHRNA1基因多态性对罗库溴铵肌松效应的影响

目的 探讨CHRNA1基因多态性对罗库溴铵肌松效应的影响.方法 择期全麻下行腹部手术患者95例,ASA分级Ⅰ或Ⅱ级,性别不限,年龄18～64岁,体重指数18～25 kg/m2,腋温36～37℃.患者来自河北省或周边地区,且均为汉族,彼此无血缘关系.术前采集外周静脉血样5 ml,EDTA抗凝,蛋白酶K消化,饱和氯化钠盐析法提取DNA.采用聚合酶链反应-限制性片段长度多态性技术和序列分析法对CHRNA1上游478 bp处AG多态性位点rs16862847进行检测,根据基因型将患者分为野生型纯合子组(AA组,n=71)、突变型杂合子组(AG组,n=19)和突变型纯合子组(GG组,n=5).人室后静脉注射芬太尼4μg/kg和异丙酚2 mg/kg,意识消失后启动TOF-Watch SX型加速度肌松监测仪单刺激模式监测拇内收肌颤搐程度,随后静脉注射罗库溴铵0.2 mg/kg,观察肌松效应.结果 与AA组相比,AG组和GG组肌松起效时肌颤搐程度降低(P＜0.05).AG组和GG组肌松起效时肌颤搐程度比较差异无统计学意义(P＞0.05).结论 CHRNA1基因多态性可影响患者罗库溴铵的肌松效应,提示遗传因素是导致肌松药药效个体差异的原因之一.     

Effect of vecuronium on atropine-induced changes in heart rate

The effect of vecuronium on the heart rate response to atropine has been studied by comparing dose-response relationships in two groups of patients who underwent extracorporeal shock wave lithotripsy. One group received vecuronium (0.1 mg/kg) and the other acted as control. Incremental doses of atropine (1.8, 1.8, 3.6, 7.2 and 14.4 micrograms/kg) were administered and changes in heart rate recorded. No significant differences were observed between the two groups following each incremental dose of atropine.     

Frequency of haemoglobin desaturation with the use of succinylcholine during rapid sequence induction of anaesthesia

BACKGROUND: The perceived safety of the use of succinylcholine is based on the fact that recovery from its effects will occur before oxygen desaturation occurs in case of failure to intubate or ventilate. The purpose of this study was to examine the incidence of oxygen desaturation after the use of succinylcholine prior to resumption of spontaneous ventilation following four different preoxygenation techniques. METHODS: Twenty-five patients each were randomly allocated to preoxygenation with 4 deep breaths of 100% oxygen or by breathing oxygen for 1, 3 or 5 min following which they received a rapid sequence induction of anaesthesia with fentanyl 1 microg kg(-1), a sleep dose of thiopentone and succinylcholine 1 mg kg(-1). Oxygen saturation was monitored continuously using a finger probe. Ventilation was not assisted unless the saturation decreased to 相似文献   

Suxamethonium induced myalgia and the effect of pre-operative administration of oral aspirin

Eighty-four fit, unpremedicated patients who presented for routine surgery and received a standard anaesthetic technique were allocated randomly to three equal groups. Group 1 received tubocurarine 0.05 mg/kg before induction of anaesthesia. Group 2 received soluble aspirin 600 mg orally one hour before surgery, while Group 3 received no pretreatment. Aspirin prophylaxis produced a significant reduction in the incidence of subsequent suxamethonium-induced myalgia and the improvement was similar to that achieved with tubocurarine pretreatment. Pre-operative oral administration of aspirin effectively reduces muscle pains and avoids many of the complications associated with pretreatment with non-depolarising agents.     

The neuromuscular transmission monitor

The neuromuscular transmission monitor (NTM) is a new device for measuring neuromuscular transmission during anaesthesia. We have assessed its use in comparison with a force transducer and found for single twitch and train-of-four modes that there was a strong positive correlation between the two methods. This device appears reliable in use and provides a satisfactory alternative to conventional neuromuscular monitoring.     

The effect of H2 antagonists on duration of action of suxamethonium in the parturient

Fifteen patients who underwent elective Caesarean section were given sodium citrate, either alone or combined with oral cimetidine or ranitidine, as antacid premedication. No significant differences in time to 25 or 50% recovery of the first twitch of a train-of-four after administration of suxamethonium were found between any of the groups. It is concluded that H2-antagonists do not significantly affect the duration of action of suxamethonium in parturients, in contrast to the findings of a study in nonpregnant patients.     

Influence of acute normovolaemic haemodilution on the dose-response and time-course of action of atracurium

BACKGROUND: Acute normovolaemic haemodilution is a common method to save and avoid homologous blood transfusion during surgery. The aim of this study was to evaluate the influence of acute isovolaemic haemodilution on the dose-response and time-course of action of atracurium. METHODS: We studied 25 patients undergoing acute isovolaemic haemodilution during surgery and 25 patients not receiving haemodilution as a control group. All patients were ASA grade I and aged 18-54 yr. The haemodilution patients underwent major elective plastic surgery with an anticipated surgical blood loss of more than 600 ml, and the control patients underwent elective superficial plastic surgery with an anticipated surgical blood loss of less than 200 ml. Anaesthesia was induced with thiopental 4-6 mg/kg and fentanyl 2-4 microg/kg i.v., and maintained with 60% nitrous oxide in oxygen. After stabilization of anaesthesia, acute isovolaemic haemodilution in the haemodilution group was achieved by drainage of venous blood and an i.v. infusion of lactated Ringer's solution, and 6% dextran, during which haematocrit and haemoglobin decreased from 45.1% to 25.8% and from 147.2 g/l to 91.2 g/l, respectively. When anaesthesia was stable in the control group and haemodilution was completed in the haemodilution group, neuromuscular function was assessed by measuring with accelerography the response of the adductor pollicis muscle to supramaximal train-of-four (TOF) stimuli every 12 s to the ulnar nerve at the wrist via surface electrodes. The dose-response relationships of atracurium in the two groups were determined by the cumulative dose-response technique. RESULTS: The results showed that during haemodilution, the dose-response curve of atracurium was shifted to the left in a parallel fashion and the potency of atracurium was increased. In patients undergoing haemodilution, ED50, ED90 and ED95 of atracurium were decreased by 25-33%, and duration of action was increased by 21-48% following administration of the same dose (mg/kg), as compared with patients not undergoing haemodilution. CONCLUSION: We concluded that the patients undergoing acute isovolaemic haemodilution were about 30% more sensitive to neuromuscular blockade of atracurium and had a longer duration after administration of the same dose (microg/kg) than the control patients. Care must be taken with this problem when atracurium is used as a muscle relaxant during acute haemodilution.     

琥珀胆碱对罗库溴铵肌松作用的影响

目的：本试验应用ＰＩ控制器自动化反馈控制罗库溴铵的输注,将肌松维持在恒定水平,通过确定罗库溴铵的稳态输注速率,来研究琥珀胆碱对罗库溴铵肌松作用的影响。方法：选择１４例ＡＳＡ分级Ⅰ～Ⅱ级的手术病人,随机分成对照组（７例）和试验组（７例）。对照组在麻醉诱导后,静注０．６ｍｇ／ｋｇ罗库溴铵进行气管插管;试验组则静注１．５ｍｇ／ｋｇ琥珀胆碱后气管插管,待肌松作用完全恢复后,再静注０．６ｍｇ／ｋｇ罗库溴铵,     

The use of neuromuscular blocking agents in noncardiac surgery after dynamic cardiomyoplasty

Dynamic cardiomyoplasty is a surgical treatment to improve cardiac performance in patients with end-stage heart failure by wrapping the latissimus dorsi muscle around the heart. The use of skeletal muscle raises concerns about the safety of neuromuscular blocking agents used during general anaesthesia in noncardiac surgery in patients after cardiomyoplasty. We describe the administration of rocuronium to a patient undergoing carotid endarterectomy 18 months after cardiomyoplasty. No clinically relevant effects on haemodynamics were observed. We conclude that the use of nondepolarising neuromuscular blocking agents for noncardiac surgery in patients after cardiomyoplasty does not compromise cardiac performance in a clinically relevant way, although the time between the cardiomyoplasty procedure and the use of nondepolarising neuromuscular blocking agents remains a concern.     

Prolonged paralysis following an infusion of alcuronium in a patient with renal dysfunction

The case is described of a patient who underwent artificial ventilation in an intensive therapy unit and received an infusion of alcuronium 10 mg/hour for more than 4 days, in the presence of significant renal (and later, some degree of hepatic) impairment. Prolonged and profound neuromuscular block persisted despite haemodialysis (5 hours on each of 3 days) followed by 72 hours of continuous haemofiltration; it appeared to resolve only after plasma exchange (4 litres). The total of persistent block, for 9 days after the infusion had been stopped, is thought to be the longest period ever reported after administration of alcuronium. Neuromuscular block was monitored throughout this period using the train-of-four twitch technique. The potentiating effects of concurrent aminoglycoside therapy and hepatic dysfunction on the degree of paralysis are discussed.     

甲氧普胺对琥珀胆碱的时－量关系及阻滞性质的影响

２０例择期普胸、脊柱手术病人随机分为１组（甲氧普胺组）和２组（对照组）。１组术前３０ｍｉｎ肌注甲氧普胺０．３ｍｇ／ｋｇ，２组未用甲氧普胺。麻醉诱导后用２％普鲁卡因复合０．０８％琥珀胆碱静滴维持麻醉，用加速度仪监测神经肌肉阻滞及阻滞性质，同时采血测定血浆胆碱酯酶活性。结果：１组肌注甲氧普胺后血浆胆碱酯酶活性下降３４．８％，与２组同时值比较有显著差异。维持肌颤搐Ｔ１１０～２０％两组琥珀胆碱用量及停药后肌张力恢复时间无明显差异，１组１０例均出现双相阻滞。结果表明，术前常规剂量甲氧普胺对琥珀胆碱的时－量关系无明显影响，但影响其阻滞性质。     

The effect of mivacurium pretreatment on intra-ocular pressure changes induced by suxamethonium

Forty patients without eye disease, undergoing elective nonophthalmic surgery, were studied in a double-blind, randomised, placebo-controlled study evaluating the efficacy of mivacurium pretreatment in attenuating the rise in intra-ocular pressure in response to suxamethonium administration, laryngoscopy and intubation. The patients were randomly allocated to receive either mivacurium 0.02 mg.kg⁻¹ or normal saline as pretreatment 3 min before a rapid sequence induction technique using alfentanil, propofol and suxamethonium. Suxamethonium induced a significant increase in intra-ocular pressure in the control group but not in the mivacurium pretreatment group (mean (SEM) increase = 3.5 (1.2) mmHg vs. 0.4 (0.8) mmHg, p < 0.05). There was a decrease in intra-ocular pressure in both groups after laryngoscopy and intubation with no significant difference between the two groups. These results show that mivacurium pretreatment is effective in preventing the increase in intra-ocular pressure after suxamethonium administration.