In vitro effects of fluoride and bromide on pseudocholinesterase and acetylcholinesterase activities

Abstract

The in vitro effects of two metabolites ofinhalational anaesthetics, fluoride and bromide, on pseudocholinesterase (PCHE) and acetylcholinesterase (ACHE) activities in the blood samples of seven healthy patients were studied. The PCHE and ACHE activities were determined by kinetic spectrophotometric methods. Fluoride at the levels achieved with clinical concentrations of enjlurane and sevoflurane (25-75 μM · L-1) inhibited PCHE activity by 28-65 per cent (P < 0.01) and ACHE activity by less than five per cent (P > 0.05). Bromide at the levels achieved with clinical concentrations ofinhalational anaesthetics had no significant effect on either PCHE or ACHE activity. We recommend caution when succinylcholine and/or ester type local anaesthetics are used in the immediate postoperative period following enflurane or sevoflurane anaesthesia. We also recommend that blood drawing for PCHE activity be delayed at least until 24 hr following enflurane or sevoflurane anaesthesia. © 1990 Canadian Anesthesiologists.