The influence of selected general anesthetics on pharmacokinetic parameters of some antiarrhythmic drugs in rabbits. Part II. N-acetylprocainamide.

The influence of general anesthesia with thiopental (10 mg/kg), ketamine (4 mg/kg), propofol (10 mg/kg) or pentobarbital (20 mg/kg) on the N-acetylprocainamide (15 mg/kg) pharmacokinetic parameters was studied in rabbits. It was established that during thiopental or pentobarbital anesthesia the levels of N-acetylprocainamide may be temporary higher than therapeutic levels. The following main changes in N-acetylprocainamide pharmacokinetic parameters were found: 1) increase of the elimination rate and shortening of biological half-life during thiopental or ketamine anesthesia 2) decrease of mean residence time during thiopental anesthesia 3) increase of the elimination rate from the central compartment constant (but not the mean residence time) during pentobarbital anesthesia 4) decrease of distribution rate and penetration rates (k12, k21) during propofol anesthesia.