A randomized, double-blinded trial of preemptive analgesia in laparoscopy

Abstract

OBJECTIVE: We tested the hypothesis that local anesthetic administered before skin incision, an example of preemptive analgesia, reduces postoperative pain for women undergoing laparoscopy, as compared with postincisional local anesthetic or placebo. METHODS: Patients undergoing diagnostic laparoscopy were randomized to one of three blinded treatment groups. Treatment group A patients received local infiltration of 0.5% bupivacaine at the surgical site before incision and a saline placebo infiltration before incision closure. Treatment group B received the saline placebo before skin incision and bupivacaine after laparoscopy but before closure of the skin incisions. For treatment group C patients, saline was infiltrated as a placebo before and after laparoscopy. All patients underwent a standardized general anesthetic induction and maintenance. Postoperative pain was evaluated using the modified McGill Present Pain Intensity scale. Pain and supplementary analgesic use was compared among the three treatment groups. RESULTS: A total of 57 patients completed the study for analysis. Age, weight, height, race, indication, and operating time did not vary significantly between the three groups. By 24 hours after surgery, patients in treatment group A reported significantly lower pain scores (McGill Present Pain Intensity Scale: 0.5+/-0.9) than either treatment group B (1.6+/-1.3) or C (1.3+/-1.2). Group A patients also could tolerate a significantly longer time delay to their first analgesic medication than patients who received postincisional bupivacaine or than control patients who received no bupivacaine. CONCLUSION: The preemptive administration of bupivacaine before laparoscopy results in decreased postoperative pain and should allow a more rapid return to normal activities. The popular practice of infiltrating bupivacaine at time of incision closure does not offer any benefit in the control of pain after laparoscopy.