Influence of pancuronium or d-tubocurarine on circulatory responses during thiamylal-N2O-halothane anesthesia.

Circulatory responses after thiamylal (4 mg/kg) and pancuronium (0.08 mg/kg, 20 patients) or d-tubocurarine (dTc, 0.5 mg/kg, 20 patients) followed by tracheal intubation and nitrous oxide-halothane administration were measured. Three minutes after thiamylal, the mean arterial pressure (MAP) and cardiac index (CI) decreased significantly only in patients receiving dTc. Heart rate (HR) was increased 12 bpm in both groups. The magnitude of reduction in MAP and CI was similar and the HR was not greatly different between groups after 5 minutes of N2O-halothane administration. MAP and CI were better maintained following thiamylal in patients receiving pancuronium as compared with dTc. However, circulatory responses during early anesthetic maintenance were not influenced by the choice of neuromuscular blocker.