Effect of a 5% lidocaine patch for postoperative pain relief following cesarean section: a randomized double-blind placebo-controlled trial.

Abstract

Introduction

Effective postoperative analgesia after cesarean section supports early mobilization, maternal-infant interaction, breastfeeding, and recovery. This study evaluated the analgesic efficacy and safety of a 5% lidocaine patch after cesarean delivery.

Materials and Methods

In this prospective, randomized, double-blind, placebo-controlled trial, 120 women undergoing cesarean section under spinal anesthesia were allocated 1:1 to a 5% lidocaine patch (n=60) or an identical placebo patch (n=60). Pain was assessed on a 0-10 numerical rating scale at 0, 2, 4, 6, 8, 12, and 24 hours. Rescue analgesic use, ambulation, satisfaction, hemodynamic variables, and adverse effects were evaluated.

Results

Baseline characteristics were comparable. Mean age was 28.7 ± 3.9 years in the lidocaine group and 29.1 ± 4.2 years in controls; mean BMI was 25.1 ± 2.8 and 25.4 ± 3.0 kg/m², respectively, and mean gestational age was 38.4 ± 0.9 and 38.3 ± 1.0 weeks. ASA I status was present in 63.3% and 60.0%, respectively. At 24 hours, pain was lower with lidocaine (2.1 ± 0.7 vs. 2.8 ± 0.9; mean difference -0.70, 95% CI -0.99 to -0.41; p<0.001). Time to first rescue analgesia was longer (8.4 ± 2.1 vs. 5.9 ± 1.8 hours; mean difference 2.50 hours, 95% CI 1.79 to 3.21), and total rescue analgesic consumption was lower (82.5 ± 34.7 vs. 121.7 ± 42.6 mg; mean difference -39.20 mg, 95% CI -53.25 to -25.15; both p<0.001). Ambulation occurred earlier and satisfaction was higher, while overall adverse effects were comparable.

Conclusion

A 5% lidocaine patch improved early postoperative analgesia and reduced rescue analgesic requirements without evidence of increased adverse effects.

Recommendation

The patch can be considered as an adjunct to multimodal post-cesarean analgesia, while larger multicenter trials should confirm effectiveness, safety, and optimal application protocols.