Randomized trial of lidocaine ointment versus placebo for the treatment of postpartum perineal pain.

Abstract

To estimate the efficacy of lidocaine ointment in relieving pain after a vaginal delivery with an episiotomy or perineal laceration. In a randomized, double-blind, placebo-controlled trial, 200 women received lidocaine ointment (n = 108) or a placebo (n = 92). Pain relief was assessed by the amount of ointment used (weight of jar before use - weight of jar after use), total number of pain pills used, and a pain questionnaire. The sample size was calculated using a beta of.2 and an alpha of.05 with an expected reduction of other pain medications from an average use of six pills to four pills for the population. There was no significant difference in the amount of lidocaine versus placebo used for postpartum day 1 (5.1 g versus 4.0 g, respectively [P =.13]) or day 2 (3.7 g versus 2.6 g, respectively [P =.18]). Patients receiving lidocaine instead of the placebo showed no significant difference in the total amount of postpartum pain medications (6.3 versus 6.8 tablets, respectively [P =.53]), subjective pain parameters (P =.36), or satisfaction from ointment (P =.99). Patients with an episiotomy used more pain medications than those with a laceration (7.9 versus 5.6 tablets, respectively [P =.003]). Those with minor versus major lacerations required fewer pain pills (6.1 versus 10.8 tablets, respectively [P <.001]) and used less ointment (4.3 g versus 7.9 g, respectively [P =.02]) on the first postpartum day. Topical application of 5% lidocaine ointment was not effective in relieving episiotomy or perineal laceration pain.