Canadian journal of anaesthesia = Journal canadien d'anesthésie
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Randomized Controlled Trial Comparative Study Clinical Trial
Clinical comparison of sevoflurane and isoflurane when administered with nitrous oxide for surgical procedures of intermediate duration.
The purpose of this study was to compare the haemodynamic effects and emergence times of anaesthesia with sevoflurane with those of isoflurane when the agents were administered with nitrous oxide to adult patients (ASA I and II) undergoing surgery of at least an hour in duration. Fifty patients were randomly assigned to receive either 0.65 minimum alveolar concentration (MAC) (1.3%) sevoflurane or 0.65 MAC (0.8%) isoflurane together with 60% nitrous oxide following induction with thiopentone, fentanyl, and succinylcholine. Systemic blood pressure and heart rate trends were similar for both groups for the duration of anaesthesia. ⋯ Recovery of response to command was more rapid after discontinuation of sevoflurane-nitrous oxide (9.9 +/- 1.1 min) than after isoflurane-nitrous oxide (13.9 +/- 1.3 min). Despite earlier emergence, patients who had received sevoflurane did not request postoperative analgesia sooner. We conclude that the purported advantages of sevoflurane, namely haemodynamic stability and rapid emergence, can be expected even when the agent is administered at 0.65 MAC (1.3%) in nitrous oxide to a typical adult surgical population undergoing procedures of intermediate duration (2.3 +/- 0.2 hr).
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Randomized Controlled Trial Clinical Trial
Attenuation of the catecholamine response to tracheal intubation with oral clonidine in children.
We conducted a prospective, randomized, double-blind , controlled clinical trial to examine (1) whether plasma catecholamine (CA) concentrations increased in response to tracheal intubation in children, and (2) the effects of clonidine on the CA responses. Sixty children (ASA physical status I) aged 7-13 yr were allocated to one of three groups (n = 20 for each group): diazepam 0.4 x kg(-1) (active control), clonidine 2 micrograms x kg(-1), or clonidine 4 micrograms x kg(-1) po. These agents were administered 105 min before induction of anaesthesia followed by oral atropine 0.03 mg x kg(-1) given 60 min before anaesthesia which was induced with thiamylal 5 mg x kg(-1) and tracheal intubation was facilitated with vecuronium 0.2 mg x kg(-1). ⋯ These haemodynamic and CA changes were smaller in children receiving clonidine 4 micrograms x kg(-1) (P < 0.005). The haemodynamic responses were positively correlated with the CA responses. These findings indicate that tracheal intubation following rapid sequence induction of anaesthesia in children provokes a reflex increase in sympathetic activity characterized by increased plasma CA concentrations, and that attenuation of the cardiovascular changes with a high oral dose of clonidine may be due to suppression of the increase in sympathetic activity evoked by the intubation.
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Randomized Controlled Trial Clinical Trial
Dose-response relationships for edrophonium antagonism of mivacurium-induced neuromuscular block during N2O-enflurane-alfentanil anaesthesia.
The purpose of this study was to determine the dose-response relationships for edrophonium antagonism of mivacurium-induced neuromuscular block. Seventy-five ASA I or II adults were given mivarcurium 0.15 mg x kg(-1) followed by an infusion (7 micrograms x kg(-1) x min(-1) during alfentanil-propofol-N2O-enflurane anaesthesia. Train-of-four stimulation (TOF) was applied to the ulnar nerve every 20 sec and the response of the adductor policis was recorded (Relaxograph NMT-100, Datex, Helsinki, Finland). ⋯ Edrophonium 0.5 mg x kg(-1) was different from placebo with regard to recovery time of T1 from 25 to 75% (T25-75) (3.3 +/- 2.0 vs 6.7 +/- 2.0 min P<0.05). Only edrophonium 0.5 mg x kg(-1) provided faster recovery than placebo with regard to all three indices. It is concluded that edrophonium 0.5 + glycopyrrolate 0.005 mg x kg(-1) allow the fastest recovery from a mivacurium-induced block during enflurane-N2O anaesthesia.
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Randomized Controlled Trial Comparative Study Clinical Trial
Prevention of postoperative nausea and vomiting with granisetron: a randomized, double-blind comparison with droperidol.
The effects of granisetron for preventing postoperative nausea and vomiting were investigated in a randomized, double-blind comparison with droperidol and placebo in 100 patients undergoing general anaesthesia for major gynaecological surgery. The patients received a single dose of either granisetron (40 micrograms x kg(-1), n = 25), droperidol (1.25 mg, n = 25; 2.5 mg n = 25) or placebo (saline, n = 25)iv over two to five minutes immediately before induction of anaesthesia. The antiemetic effects of these drugs were evaluated during the first three and the next 21 hr after recovery from anaesthesia. ⋯ The efficacy of granisetron in preventing postoperative nausea and vomiting was almost equal to that of droperidol 2.5 mg. The awakening time in the patients who had received droperidol 2.5 was prolonged by approximately three minutes compared with the placebo group (P <0.05), and postoperative drowsiness/sedation was observed in these patients. In conclusion, preoperative prophylactic administration of granisetron is superior to that of droperidol in the prevention of postoperative nausea and vomiting after anaesthesia.