Effect of buprenorphine on the need for labor epidural supplementation
Abstract Number: F-2
Abstract Type: Original Research
Introduction: Up to 3% of the 4.1 million women of child-bearing age who abuse drugs continue drug use during pregnancy.(1) Methadone and Buprenophine (Bup) have been used in the peripartum period to treat opioid addiction.
The µ receptor agonist, Methadone, is the standard of care in the opioid-abusing pregnant patient. This standard is now being challenged with the agonist-antagonist Buprenophine. Studies suggest Bup is safe and effective during pregnancy and has shown reduced severity of Neonatal Abstinence Syndrome when compared to Methadone (2). While bup’s unique pharmacology contributes to its benefits, it may make labor pain management challenging for the OB anesthesiologist. Our aim was to assess the effect of Bup on labor pain management.
Methods: We conducted a retrospective case-control study of pregnant patients on bup therapy compared to those not taking this therapy. Patients were included if they were taking bup during pregnancy between 4/2010-4/2011, labored prior to delivery, and received epidural analgesia for labor. Controls were un-matched and randomly selected from among all the labor epidurals at our institution in a six day period in 01/2012. All patients received a standard epidural bolus of 10 mL of 0.083% bupivacaine and 116 mcg of fentanyl immediately after epidural placement and test dose. The infusion rate and PCEA were programmed consistently for all patients with an 8 mL basal infusion of 0.083% bupivicaine and fentanyl 2 mcg/ml, an 8 mL demand bolus, and an 8 minute lockout with a 1 hour maximum of 24 mL. When breakthrough pain occurred under these PCEA parameters, patients were evaluated and a lidocaine bolus was given by the Anesthesiology staff. The primary endpoint was the supplemental bolus. Incidence of boluses were compared between cases and controls using a Fisher’s exact test . A p-value of less than 0.05 was considered statistically significant.
Results: Fourty one pregnant patients at our institution were found to be taking Bup and 33 met inclusion requirements for this study. Among the cases, 11 patients required additional epidural boluses, with 1 patient requiring 2 boluses. Sixty six patients formed the control group of which, 6 patients required additional boluses. The incidence of re-bolusing was significantly higher in the buprenorphine group (P = 0.003) with a relative risk of 5.500 (95% CI 1.182-16.62).
Conclusions: Bup’s pharmacology may increase this population’s analgesic requirement.
(1)Substance Abuse and Mental Health Services Administration Office of Applied Studies. 2003 National Survey on Drug Use & Health: Results. US Department of Health and Human Services. http://www.drugabusestatistics.samhsa.gov/NHSDA/2k3NSDUH/2k3results.htm.
(2)Jones HE, Kaltenbach K, Heil SH, Stine SM, Coyle MG, Arria AM, O'Grady KE,
Selby P, Martin PR, Fischer G. Neonatal abstinence syndrome after methadone or
buprenorphine exposure. N Engl J Med. 2010 Dec 9;363(24):2320-3