Serum concentrations of local anaesthetics following intraperitoneal administration during laparoscopy

The present study is a comparison of the pharmacokinetics of four local anaesthetics injected double blind in the right subdiaphragmatic area during outpatient laparoscopy performed under standard general anaesthesia in 28 young women. 80 ml of one of the following solutions was injected: Group A 0.5% plain lidocaine (n = 7), Group B 0.5% lidocaine with 1/320.000 adrenaline (n = 8), Group C 0.5% lidocaine with 1/800.000 adrenaline (n = 7), and Group D 0.125% bupivacaine with 1/800.000 adrenaline (n = 6). Blood samples were collected over 360 min from an iv catheter and serum concentrations were measured by gas chromatography. No adverse effects occurred in the study period. In Group A (plain lidocaine), Cmax was significantly higher and tmax significantly earlier than in Groups B and C (lidocaine with adrenaline). A toxic level was not found after either solution in any patient. The intraperitoneal use of doses of 400 mg lidocaine or 100 mg bupivacaine for perioperative analgesia was safe and solutions of lidocaine containing adrenaline appeared to pose even less risk than plain solutions.