Abstract
The time course of arterial plasma lidocaine concentration, following an epidural anaesthesia via the sacrococcygeal or the S4-S5 trans-sacral approach, was studied in nine healthy piglets (7.8±1.3 weeks). Plasma lidocaine concentrations were measured for up to six hours after administration (5 mg/kg). Peak plasma concentration was 1.83±0.17 mg/l. Pharmacokinetic parameters determined from an independent compartment model were not different from those observed after an epidural administration of lidocaine via the sacrococcygeal space in children, except for a wide variability in the time taken to reach the maximum concentration (27.3±7.4 min) and a shorter half-life of elimination (82.8±7.0 min). The total body clearance of lidocaine was similar in piglets (17.3±1.6 ml/min/kg) to that in children. The shorter half-life of elimination was therefore attributed to a smaller volume of distribution in piglets (2.0±0.21/kg).