Transversus Abdominis Plane Block for Analgesia in Renal Transplantation: A Randomized Controlled Trial
The transversus abdominis plane (TAP) block has proven effective in reducing opioid requirements and pain scores for some procedures involving the lower abdominal wall. In this study we assessed its efficacy in patients with end-stage renal failure undergoing cadaveric renal transplantation. Sixty-five adult renal transplant recipients were prospectively randomized to receive a standard general anesthetic technique supplemented with levobupivacaine 0.375% 20 mL TAP block or sham block with 20 mL 0.9% saline. Both groups received patient-controlled morphine analgesia and acetaminophen. Patient assessment occurred in the postanesthetic care unit and at 2, 4, 6, 12, and 24 hours. The primary outcome was total morphine consumption in the first 24 hours after renal transplantation. Other outcomes assessed included pain scores, presence of nausea or vomiting, excessive sedation, and respiratory depression. Morphine requirements did not differ between the 2 groups, 31.6 ± 5.6 mg in the TAP group and 32.6 ± 5.5 mg in the control group (95% confidence interval [CI], -8.96 to 7.09, P = 0.817). Pain scores also did not differ significantly at any time point after surgery. Nausea was reported in 53% of the TAP group and 24% of the control group. The relative risk of nausea associated with treatment was 2.2 (95% CI, 1.1 -4.3, P = 0.017). No patient exhibited excessive sedation or respiratory depression. The addition of a TAP block to the analgesia regimen for renal transplantation did not reduce morphine requirements.