Efficacy of Preemptive Analgesia for Wound Pain After Laparoscopic Operations in Infertile Women: A Randomized, Double-Blind, and Placebo-Controlled Study

Abstract

This randomized, double-blind, placebo-controlled study was conducted to evaluate postoperative pain control with preemptive analgesia, preclosure analgesia, or placebo in women undergoing laparoscopy for treatment of infertility. One hundred forty-four women scheduled to undergo laparoscopy were recruited from the infertility clinic. There were 48 members of each group. Those randomized to the preemptive group received 1% lignocaine before the incision and normal saline before wound closure; those in the preclosure group received normal saline before the incision and 1% lignocaine before wound closure. Women in the control group were given normal saline at both times. For all 3 groups, the assistant scrub nurse placed the appropriate solution in syringes labeled or preclosure. The contents of the syringes were unknown to all other operating personnel and the patient. The solutions were administered using the same technique for all groups. Before the incision was made, approximately 3 cc of the preincision solution was administered above and below the fascia at the site of the periumbilical trocar. An additional 3 cc was used in the subcutaneous tissue at ancillary trocar sites. Before the incision was closed, the preclosure solution was infiltrated into the wound. Postoperative pain was measured by having the patient pinpoint the level of her pain along a line ranging from zero (no pain) to 100 (most severe pain). Assessments were made at 2 hours, 4 hours, and by self-report at 24 hours. One patient from the preemptive group and 2 from the placebo group could not be contacted for the 24-hour measure. The clinical and physical characteristics of the 3 groups were comparable. At 2 hours, median pain scores were 25 for the preemptive group, 16.5 for the preclosure group, and 37.5 for the placebo group. At 4 hours, scores were 19.5, 7.0, and 21.5, respectively; and at 24 hours, they were 15.0, 9.0, and 19.5, respectively. The preclosure group had lower median pain scores at all 3 postoperative assessments. The preclosure score was significantly better than the placebo group at 2 hours (16.5 vs. 37.5, P = 0.001), 4 hours (7.0 vs. 21.5, P = 0.023), and 24 hours (9.0 vs. 19.5, P = 0.005). At 24 hours, the preclosure was also significantly lower than the preemptive score (9.0 vs. 15.0, P = 0.025). Preemptive scores were significantly better than placebo only at 2 hours (25 vs. 37.5, P = 0.016). The total postoperative analgesic requirements were similar across all 3 groups.