Transversus abdominis plane block in renal allotransplant recipients: A retrospective chart review

CONTEXT: The efficacy of the transversus abdominis plane (TAP) block appears to vary considerably, depending on the surgical procedure and block technique. AIMS: This study aims to add to the existing literature and provide a more clear understanding of the TAP blocks role as a postoperative analgesic technique, specifically in renal allotransplant recipients. SETTINGS AND DESIGN: A retrospective chart review was conducted by querying the intraoperative electronic medical record system of a 1200-bed tertiary academic hospital over a 5 months period, and reviewing anesthetic techniques, as well as postoperative morphine equivalent consumption. MATERIALS AND METHODS: Fifty renal allotransplant recipients were identified, 13 of whom received TAP blocks while 37 received no regional analgesic technique. All blocks were performed under ultrasound guidance, with 20 mL of 0.25% bupivacaine injected in the transversus abdominis fascial plane under direct visualization. The primary outcome was postoperative morphine equivalent consumption. STATISTICAL ANALYSIS USED: Morphine consumption was compared with the two-tailed Mann–Whitney U-test. Continuous variables of patient baseline characteristics were analyzed with unpaired t-test and categorical variables with Fischer Exact Test. A P < 0.05 was considered statistically significant. RESULTS: A statistically significant decrease in cumulative morphine consumption was found in the group that received the TAP block at 6 h (2.46 mg vs. 7.27 mg, P = 0.0010), 12 h (3.88 mg vs. 10.20 mg, P = 0.0005), 24 h (6.96 mg vs. 14.75 mg, P = 0.0013), and 48 h (11 mg vs. 20.13 mg, P = 0.0092). CONCLUSIONS: The TAP block is a beneficial postoperative analgesic, opiate-sparing technique in renal allotransplant recipients.