British journal of anaesthesia
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Randomized Controlled Trial Clinical Trial
Administration of magnesium sulphate before rocuronium: effects on speed of onset and duration of neuromuscular block.
The speeds of onset of pancuronium, atracurium and vecuronium are increased by prior administration of magnesium sulphate. A prospective, randomized, double-blind, controlled, clinical study was performed to examine the effects of prior i.v. administration of magnesium sulphate 60 mg kg-1 on the neuromuscular blocking effects of rocuronium 0.6 mg kg-1 during isoflurane anaesthesia. ⋯ Administration of magnesium sulphate was not associated with adverse haemodynamic effects. Prior administration of magnesium sulphate, under the study conditions described, prolonged rocuronium-induced neuromuscular block but did not increase speed of onset.
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Randomized Controlled Trial Clinical Trial
Quantitative study of Lowe's square-root-of-time method of closed-system anaesthesia.
Intermittent injection of liquid anaesthetic into a closed breathing system is particularly suitable in countries with limited resources. A method of calculating appropriate times and magnitudes of the injected doses was described by Lowe but the method has never been assessed rigorously. Such an assessment was the purpose of this study. ⋯ However, end-tidal partial pressure (just before each dose) stabilized at a steady level of only 0.97, 0.42 and 0.77 MAC for halothane, enflurane and isoflurane, respectively. Recovery from enflurane was much more rapid than that from the other agents but no patient admitted to any dreams. We conclude that the rate of uptake of anaesthetic declines more slowly than predicted and that the patients receiving enflurane were less deeply anaesthetized because the greater hypotensive effect of enflurane led to the use of smaller doses.
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Randomized Controlled Trial Clinical Trial
Extradural buprenorphine suppresses breast feeding after caesarean section.
Satisfactory pain relief with postoperative extradural bupivacaine increases the amount of breast feeding after Caesarean section. To investigate the effect of extradural buprenorphine, we have evaluated the amount of breast feeding and the gain in infant weight for 11 days after Caesarean section in patients who received continuous extradural bupivacaine with or without buprenorphine. Extradural buprenorphine significantly decreased both measures although there was no significant difference in pain intensity. We suggest that extradural buprenorphine suppressed breast feeding after Caesarean section.
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Randomized Controlled Trial Comparative Study Clinical Trial
Interactions between mivacurium and pancuronium.
We have compared the dose-response relationships of mivacurium, pancuronium and their combination, and examined the interactions by isobolographic and fractional analyses. We studied 70 adult patients during nitrous oxide-fentanyl-propofol anaesthesia. The dose-response curves were determined by probit analysis. ⋯ When the first twitch (T1) of TOF recovered to 25%, each patient received mivacurium 46.2 micrograms kg-1. The times after administration of mivacurium until T1 25% in the mivacurium-pancuronium group were 6.4 (3.5-9.4) min and 49.8 (44.7-54.9) min, respectively (P < 0.0001). We conclude that the combination of mivacurium and pancuronium was synergistic and after pancuronium-induced neuromuscular block, mivacurium became a longer acting agent than the shorter agent.
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Randomized Controlled Trial Clinical Trial
Plasma dilution and the rate of infusion of Ringer's solution.
Changes in the volume of the fluid space expanded by i.v. infusion of Ringer's acetate solution have been analysed recently using mathematical models. Data obtained by such analyses allow simulation of the dilution of the plasma volume during infusion of the solution at different rates. To obtain basic kinetic data for such simulations, the plasma dilution-time curves were measured during and after i.v. infusion of Ringer's solution 25 ml kg-1 over 30 min in 15 healthy male volunteers (mean age 31 yr) and over 30, 45 and 80 min in six females (mean age 32 yr). Based on these experiments, nomograms were constructed from which the rate of infusion of Ringer's solution and the infusion time required to obtain a defined plasma dilution in both males and females can be estimated together with the infusion rate needed to maintain the dilution at the level reached.