///2010 Abstract Details
2010 Abstract Details2018-05-01T17:52:49+00:00

Postpartum pain is greater in smokers

Abstract Number: 71
Abstract Type: Original Research

James C. Eisenach M.D.1 ; Laurel P. Eisenach B.A.2

Introduction

Nicotine produces complex and opposing actions on sensory biology and pain, reflecting actions on multiple receptor subtypes and processes of desensitization and changes in receptor number. In some studies, smokers experience less postoperative pain, but the influence of smoking on pain after vaginal or cesarean delivery has been relatively unexplored.

Methods

A secondary, interim analysis was performed using data from the Pain after Delivery (PAD) study, an international, multicenter observational study examining a range of factors associated with postpartum pain after delivery. This interim analysis, shown in Results, indicated worsened postpartum pain in smokers. We therefore received a separate IRB approval to supplement the PAD data with specific questions regarding smoking history and postoperative analgesic consumption in a group of 24 women who were smokers up to the current pregnancy and having elective cesarean delivery at Wake Forest University.

Results

At the time of the interim analysis, there were 815 women with vaginal delivery (23% of whom smoked) and 317 women with cesarean delivery (30% of whom smoked). For those with vaginal delivery, average pain for the previous 24 hr after delivery was greater in smokers than non-smokers (3.9 0.1 vs 3.4 0.2), as was worst pain during that period (5.4 0.1 vs 4.9 0.2). For those with cesarean delivery, only worst pain was greater in smokers (6.9 0.2 vs 5.9 0.3). These differences were significant at P<0.001.

Of the 24 women in the supplemental data study, 12 quit smoking in the first trimester, 2 in the second trimester, and 10 continued to smoke until delivery. Worst pain for the previous 24 hr after delivery in those who continued to smoke (6.9 1.0) was numerically identical to the larger interim analysis above. Worst pain for those who had quit smoking during pregnancy was 6.5 0.6, not different from those who continued to smoke. Opioid use in the post anesthesia care unit and on the wards by patient controlled analgesia did not differ between current and former smokers.

Discussion

These data suggest that postpartum pain is increased in women who continue to smoke throughout pregnancy. Whether this relates to acute nicotine withdrawal is uncertain. The difference in pain score, although statistically significant, was small and of uncertain clinical relevance. However, smoking status should be included in statistical approaches taken to analgesic trials in the postpartum period.

PAD Investigators: James Eisenach, Timothy Houle, Ruth Landau, Patricia Lavandhomme, Peter Pan, Richard Smiley

SOAP 2010