Anesthesiology
-
Randomized Controlled Trial Comparative Study Clinical Trial
Comparison of a chloroprocaine--bupivacaine mixture with chloroprocaine and bupivacaine used individually for obstetric epidural analgesia.
Continuous lumbar epidural anesthesia was instituted in 49 healthy parturients who were randomly assigned to three treatment groups: 14 patients received chloroprocaine, 3 per cent; 19 received bupivacaine, 0.5 per cent, and 16 received a mixture containing chloroprocaine, 1.5 per cent, and bupivacaine, 0.375 per cent. Observations relating to the characteristics of the anesthetic block and to maternal and fetal well-being were made by a trained nurse observer. ⋯ No clinical superiority could be demonstrate for the mixture as compared with bupivacaine or chloroprocaine used individually. There was no sign of material or fetal toxicity with any of the three treatment regimens.
-
To establish whether the plasma concentration of pancuronium reflects magnitude of neuromuscular blockade, the authors determined times of recovery from neuromuscular blockade and associated plasma concentrations following equipotent doses of pancuronium using three methods of pancuronium administration: the isolated-arm technique in conscious volunteers (n = 4), and the bolus intravenous injection (n = 7) and continuous-infusion methods (n = 3) in anesthetized patients. Although maximum depressions of twitch tension were similar (85 +/- 11,91 +/- 6, and 92 +/- 4 per cent, respectively) with the three techniques, times to recovery from neuromuscular blockade differed significantly, being 10 +/- 2 min with the isolated-arm technique, 23 +/- 7 min with the bolus-injection technique, and 46 +/- 5 min with the continuous-infusion method. ⋯ At 25 and 75 per cent recovery, mean plasma concentrations were 0.07 +/- 0.01 and 0.04 +/- 0.01 microgram/ml in the isolated arm; 0.13 +/- 0.04 and 0.09 +/- 0.02 microgram/ml after bolus injection, and 0.20 +/- 0.04 and 0.11 microgram/ml during continuous infusion, respectively. It is concluded that the relationship between plasma concentration of pancuronium and magnitude of neuromuscular blockade depends on the method of pancuronium administration.
-
The ability of edrophonium to reverse the nondepolarizing neuromuscular blockade produced by pancuronium was studied in 40 adult patients during light nitrous oxide--enflurane anesthesia. Antagonism of paralysis was attempted when the train-of-four fade ratio had spontaneous recovered in various extents. ⋯ When the train-of-four count was three or fewer visible twitches, the response to endrophonium was unpredictable. No evidence of recurarization was seen.