NO EFFECT OF CONTINUOUS I.P. INFUSION OF BUPIVACAINE ON POSTOPERATIVE ANALGESIA, PULMONARY FUNCTION AND THE STRESS RESPONSE TO SURGERY

In a double-blind prospective study, 20 patients undergoing major abdominal surgery were allocated randomly to receive a continuous 8-h i.p. infusion of either physiological saline or 0.25% bupivacaine 20 ml h-1 (in saline) following a loading dose of saline 1 ml kg −1 or 0.25% bupivacaine 1 ml kg −1 on entering the peritoneum. The following variables were measured before and at 2-h intervals during the infusion: serum glucose and cortisol concentrations, forced vital capacity, forced expiratory volume in the first second, peak expiratory flow rate and pain at rest, on mobilization and on coughing (visual analogue scale). Postoperative pain, impairment in pulmonary function and increase in serum cortisol and glucose concentrations were not influenced by the i.p. infusion of bupivacaine when compared with saline. This study shows that the i.p. instillation of therapeutically safe doses of bupivacaine was without effect in the management of pain, postoperative pulmonary dysfunction and the stress response in this group of patients.