Comparison of continuous intravenous lidocaine versus transversus abdominis plane block for kidney transplant surgery: a randomized, non-inferiority trial.

Background And Objectives: Transversus abdominis plane (TAP) blocks are associated with an improvement in postoperative analgesia following kidney transplant surgery. However, these blocks carry inherent risk and require a degree of expertise to perform successfully. Continuous intravenous lidocaine may be an effective alternative. In this randomized, non-inferiority study, we hypothesized that a continuous lidocaine infusion provides similar postoperative analgesia to a TAP block.

Methods: Subjects presenting for kidney transplant surgery were randomized in a 1:1 ratio to either an ultrasound-guided unilateral, single-injection TAP block (TAP group) or a continuous infusion of lidocaine (Lido group). The primary outcome of this non-inferiority study was opioid consumption within the first 24 hours following surgery. Secondary outcomes included pain scores, patient satisfaction, opioid-related adverse events, time to regular diet, and persistent opioid use.

Results: One hundred and twenty subjects, 59 from the TAP group and 61 from the Lido group, completed the study per protocol. Analysis of the primary outcome showed a cumulative geometric mean intravenous morphine equivalent difference between the TAP (14.6±3.2 mg) and Lido (15.9±2.4 mg) groups of 1.27 mg (95% CI -4.25 to 6.79; p<0.001), demonstrating non-inferiority of the continuous lidocaine infusion. No secondary outcomes showed clinically meaningful differences between groups.

Conclusions: This study demonstrates that a continuous infusion of lidocaine offers non-inferior postoperative analgesia compared with an ultrasound-guided unilateral, single-injection TAP block in the first 24 hours following kidney transplant surgery.

Trial Registration Number: NCT03843879.