Randomized controlled double-blind trial of transversus abdominis plane block versus trocar site infiltration in gynecologic laparoscopy

OBJECTIVE: The objective of the study was to determine whether transversus abdominis plane (TAP) block reduces postoperative pain when compared with trocar site infiltration of bupivacaine in gynecological laparoscopy. STUDY DESIGN: This was a prospective, randomized, double-blinded clinical trial using patients as their own controls. Women undergoing gynecologic laparoscopy using a 4-port symmetrical technique were randomly assigned to right-or left-sided TAP block using 30 mL of 0.25% bupivacaine with epinephrine. Two cohorts of patients were studied. Cohort 1 consisted of anesthesiologist-administered ultra-sound-guided TAP block. Cohort 2 consisted of surgeon-administered laparoscopic-guided TAP block. In both cohorts, contralateral port sites were infiltrated with an equal amount of bupivacaine in divided doses. All patients received intraoperative acetaminophen and ketorolac. Postoperative abdominal pain was assessed at 1, 2, 4, 6, 8, 12, 18, 24, and 48 hours on the block and contralateral sides, before and after palpation, using the 10 point visual analog scale. A 2 point difference in the reported pain scores was considered clinically meaningful. RESULTS: Eighty-eight patients were eligible for statistical analysis: 45 and 43 patients in cohorts 1 and 2, respectively. In both cohorts, most patients reported equal pain on the block side and local side. In cohort 1, there was a statistically significant difference in mean reported pain scores at 2 hours and across time favoring the ultrasound-guided block; however, this did not reach clinical significance. There was no statistically significant difference found at all other time points or when pain scores were objectively assessed after palpation of the incisions. When comparing laparoscopic-guided block with local infiltration, there was no statistically significant difference in reported mean pain scores at all time points or after palpation. CONCLUSION: As part of this multimodal analgesic regimen, neither block method provided a significant clinical benefit compared with trocar site bupivacaine infiltration.