The Buprenorphine Patient: A Growing Challenge for the Oral and Maxillofacial Surgeon
Subutex® and Suboxone®, which are administered sublingually, contain buprenorphine. Suboxone® contains naloxone in addition to buprenorphine in a 1:4 mixture, respectively. Unlike methadone, Suboxone’s® abuse potential is minimal because of the competitive antagonist effects of naloxone when introduced parenterally and the ceiling effect of buprenorphine (32mg) when taken sublingually. Taken as directed, the long half-life and ceiling effect of buprenorphine provides chronic pain relief or treatment of opioid dependence without the need for stringent monitoring often required with methadone therapy. Buprenorphine can be prescribed in a convenient one month supply. The use of buprenorphine for managing opioid dependence has been associated with improvement in education, social life, and toxicological conditions when compared with methadone.1 This improvement is likely due to the less restrictive outpatient management in a physician’s office instead of a methadone clinic.
Buprenorphine is a semi-synthetic opioid with kappa receptor antagonism and mu receptor partial agonism with a potency 25-100 times that of morphine.2,3 Buprenorphine’s high affinity for the mu receptor displaces other opioids from receptors, rendering them ineffective. Buprenorphine undergoes hepatic metabolism via CYP3A4 enzymes with an elimination half-life 24–60 hours (37 mean).4 Additionally, a 32mg ceiling effect achieved with buprenorphine avoids the abuse and overdose potential found with other opioids. The high affinity, long half-life, and ceiling effect of buprenorphine have made it a popular choice to replace methadone in chronic pain and opioid dependent patients.5 Displacement of opioids from opioid receptors, however, complicates the management of patients that require oral and maxillofacial surgery. Decreased efficacy of opioids used for procedural sedation and inadequate analgesia complicate the management of patients taking Suboxone® or Subutex®.
Traditional use of opioids for IV sedation and post-operative pain management will not be effective in patients taking buprenorphine (Suboxone®/Subutex®). The high affinity of buprenorphine blocks the effects of additional opioids and interferes with the synergistic effects seen when used in combination with other sedative-hypnotic medications. For procedural sedation, benzodiazepines coupled with propofol titration or continuous infusion should be considered for sedating patients taking buprenorphine. Other general anesthetics such as ketamine or inhalational anesthetics would also be effective.
Because buprenorphine interferes with opioids routinely used for post-operative pain relief, management strategies should be established in advance of surgery. Several options have been recommended by pain specialists involving high doses of opioids, increasing the dose of buprenorphine (if below the ceiling dose), peripheral nerve catheters, and transition periods to methadone.6 These adjustments should be done in consultation with the patient’s pain physician. Limitation of the magnitude of the surgery should be considered if significant post-operative pain is expected or extensive procedures are required. Long-acting local anesthetics, pre and post-operative NSAIDS (ketorolac or ibuprofen), acetaminophen, as well as IV corticosteroids pre-operatively followed by a 3 to 4 day course of oral corticosteroids post-operatively are recommended.
Buprenorphine use is a new and increasing challenge in oral and maxillofacial surgery. Consideration of buprenorphine’s pharmacology and communication with the patient’s buprenorphine prescriber should ensure that patients taking buprenorphine can be safely managed by the oral and maxillofacial surgeon.