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. The ED95 and ED50 values for mivacurium were 84.2 (95% confidence interval 80.2-88.1) micrograms kg-1 and 46.2 (40.2-52.1) micrograms kg-1, respectively. Corresponding values for pancuronium were 68.5 (63.7-73.2) micrograms kg-1 and 40.7 (35.5-45.9) micrograms kg-1, respectively. Isobolographic and fractional analyses of the mivacurium-pancuronium combination demonstrated a synergistic interaction. An additional 30 patients were allocated randomly to receive either mivacurium 84.2 micrograms kg-1 (n = 15) or pancuronium 68.5 micrograms kg-1 (n = 15). 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.
Kim
S
S
Department of Anaesthesiology, College of Medicine, Hanyang University Hospital, Seoul, Korea.
Shim
J C
JC
Kim
D W
DW
D000328:Adult; D000768:Anesthesia, General; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005260:Female; D006801:Humans; D007546:Isoquinolines / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D000077590:Mivacurium; D019148:Neuromuscular Blockade; D009469:Neuromuscular Junction / Q000187:drug effects*; D003473:Neuromuscular Nondepolarizing Agents / Q000494:pharmacology*; D010197:Pancuronium / Q000494:pharmacology*
D007546:Isoquinolines; D003473:Neuromuscular Nondepolarizing Agents; D000077590:Mivacurium; D010197:Pancuronium