Self-Reported Opioid Allergy: Obstetrical Outcomes and Postpartum Pain Management [29P

Abstract

INTRODUCTION: To determine how obstetrical outcomes and inpatient postpartum pain management are affected by self-reported opioid allergy (SROA). METHODS: Retrospective cohort study of singleton deliveries at >=37 weeks of gestation at a tertiary hospital from 2013-2016. Patients were excluded for NSAID allergies, drug abuse history, positive urine toxicology, general anesthesia for delivery, and incomplete records. The primary outcomes evaluated were mode of delivery and medications administered for inpatient postpartum analgesia. RESULTS: A total of 21,225 deliveries were included: 289 with SROA and 20,936 without SROA. In the SROA group, 29 reported reactions suggestive of true allergies (i.e. severe, life-threatening, hypersensitivity reactions). Among this subgroup, 51.7% (n=15) received opioids from the same chemical class (phenanthrenes) as their stated allergy. Women in the SROA group were older and more likely to be white and multiparous. The SROA group had a higher primary cesarean delivery rate (36.0% vs. 21.7%; P<0.0001) and overall cesarean delivery rate (58.1% vs. 35.3%; P<0.0001). Among cesarean deliveries, there was a small reduction in inpatient postpartum opioid analgesia in the SROA group compared to the non-SROA group (73.8% vs. 80.5%, respectively; P<0.04); no difference was noted among vaginal deliveries. Women in the SROA group who received opioids were more likely to receive multiple opioid medications (15.1% vs. 8.2%; P<0.005). CONCLUSION: True opioid allergy is rarely encountered in obstetrics. Women with SROA receive inpatient postpartum opioid analgesia at similar rates to those without SROA. Patients prone to adverse medication effects may be at increased risk for cesarean delivery.