Intraperitoneal nebulization of ropivacaine for pain control after laparoscopic cholecystectomy: a double-blind, randomized, placebo-controlled trial

Background. Intraperitoneal local anaesthetic nebulization is a relatively novel approach to pain management after laparoscopic surgery. This randomized, double-blind, placebo-controlled trial evaluated the effects of intraperitoneal ropivacaine nebulization on pain control after laparoscopic cholecystectomy. Methods. Patients undergoing laparoscopic cholecystectomy were randomized to receive intraperitoneal nebulization of ropivacaine 1% (3 ml) before surgical dissection and normal saline 3 ml at the end of surgery (preoperative nebulization group); intraperitoneal nebulization of normal saline 3 ml before surgical dissection and ropivacaine 1% (3 ml) at the end of surgery (postoperative nebulization group); or intraperitoneal nebulization of normal saline 3 ml before surgical dissection and at the end of surgery (placebo group). Intraperitoneal nebulization of ropivacaine or saline was performed using the Aeroneb Prow device. Anaesthetic and surgical techniques were standardized. The degree of pain on deep breath or movement, incidence of shoulder pain, morphine consumption, and postoperative nausea and vomiting were collected in the post-anaesthesia care unit and at 6, 24, and 48 h after surgery. Results. Compared with placebo, ropivacaine nebulization significantly reduced postoperative pain (-33%; Cohen's d 0.64), referred shoulder pain (absolute reduction -98%), morphine requirements (-41% to -56% Cohen's d 1.16), and time to unassisted walking (up to -44% Cohen's d 0.9) (P<0.01). There were no differences in pain scores between ropivacaine nebulization groups. Conclusions. Ropivacaine nebulization before or after surgery reduced postoperative pain and referred shoulder pain after laparoscopic cholecystectomy. Furthermore, ropivacaine nebulization reduced morphine requirements and allowed earlier mobility.