Time course of muscle relaxation with a combination of pancuronium and tubocurarine.

A combination of pancuronium and d-tubocurarine is associated with potentiation of the neuromuscular blocking effects of each drug used singly. The time to onset of maximum block and the time to 25% recovery after administration of equipotent (ED95) doses of pancuronium (0.07 mg/kg) alone, d-tubocurarine (0.51 mg/kg) alone, and pancuronium (0.024 mg/kg) in combination with d-tubocurarine (0.144 mg/kg) were studied in three groups of 10 patients each. The time to onset of maximum block was slightly but not significantly shorter with the combination (3.5 min) than with pancuronium (4.78 min) or d-tubocurarine (4.88 min). The time to 25% recovery with the pancuronium-d-tubocurarine combination (39.7 min) was significantly shorter than it was after d-tubocurarine (57.6 min) but not significantly different from pancuronium (54.4 min). The combination of pancuronium and d-tubocurarine also was associated with greater cardiovascular stability.