The Fate of Pancuronium Bromide in Man

The fate of pancuronium bromide has been investigated in 20 anaesthetized patients, seven undergoing cholecystectomy with choledochostomy (Group I), seven undergoing cholecystectomy only (Group II) and six undergoing pelvic operations (Group III). A fluorimetric method was used to determine pancuronium bromide and its bis‐quaternary derivatives in blood, urine and bile. After a single intravenous injection of 6 mg pancuronium bromide, disappearance of the drug from the plasma proceeded in three phases with half‐lives of < 5 min, 7‐13 min and 108–147 min, respectively. Renal elimination is suggested as the major excretory pathway in man, but biliary excretion is also significant. Thirty hours after injection, the total recovery of unchanged pancuronium and its metabolite was approximately 37–44% in the urine (Groups I, II, III) and 11% in the bile (Group I). Only one metabolite (3‐hydroxy derivative) of pancuronium bromide, accounting in total for about 15% of the administered dose, was identified in urine and 5% in bile by thin‐layer chromatography. Renal and hepatic elimination varied widely between patients.