Pain control after thoracotomy: bupivacaine versus lidocaine in continuous extrapleural intercostal nerve blockade

Background. The use of a continuous bupivacaine extrapleural intercostal nerve block after posterolateral thoracotomy has been shown in randomized controlled studies to be effective in reducing postoperative pain and restoring pulmonary function. It is our hypothesis that when using a continuous infusion for nerve block, a long-acting agent (bupivacaine) is unnecessary and a shorter-acting agent (lidocaine) would offer equivalent results with less systemic toxicity. This study was designed to determine whether lidocaine was as effective as bupivacaine in a continuous extrapleural intercostal nerve block after posterolateral thoracotomy because lidocaine is a less toxic analgesic agent. The study was prospectively randomized and double-blinded. Methods. Forty-six patients undergoing elective posterolateral thoracotomy were randomized to blindly receive bupivacaine (n = 23) or lidocaine (n = 23) by continuous infusion pump through an intraoperatively placed indwelling extrapleural catheter. Postoperative pain was assessed for 48 hours by patient-controlled morphine consumption and by linear visual analog scale. There was no statistically significant difference in age, sex, or type of operation between the two groups. Results. There was no statistically significant difference between the bupivacaine and lidocaine groups in patient-controlled morphine use or in visual analog scale scores. Conclusions. Lidocaine offers equivalent pain control to bupivacaine when administered for continuous extrapleural intercostal nerve block after posterolateral thoracotomy, with less risk of systemic toxicity.