Split Dosing Dogma for Methadone-Maintained Inpatients with Acute Pain and Opioid Use Disorder: A Mixed-Methods Characterization of A Future Study Population

Abstract:

Background: It is recommended that opioid use disorder (OUD) patients who are stable on methadone remain on their maintenance dose during inpatient admissions (Smith et al., 2022), and adequate analgesia is vital to providing humane care and continuing engagement (Veazie et al., 2020). Data from pain literature suggest that methadone’s analgesic effect is about 6-8 hours, so it is recommended to split the maintenance dose into 2 or more divided doses throughout the day (Fishman et al., 2002; Smith et al., 2022). However, anecdotal experience suggests otherwise and data to support this practice for OUD inpatients are lacking.

Methods: In anticipation of a future prospective study on split dosing, we queried our electronic health record (EHR) for a population of OUD patients who were stable on methadone upon admission to our hospital. We characterized their patient-level (e.g., stable methadone dose) and encounter-level (e.g., pain scores, pain management satisfaction) parameters. Relevant quotations are included from a patient about his split-methadone experience, recorded with written consent.

Results: Over 24 months, 162 met criteria for methadone “stability” (enrollment verified, last dose within 3d of admission, dose continued). Primary teams were 64.2% medical, 25.3% surgical, and 10.5% psychiatric. At least 30.1% had an addiction consultation. Upwards of 71.0% had average pain scores (numerical rating scale range 0-10) 4 or higher, incorporating up to 7 days of admission. Mean pain scores were 4.1. “Satisfied with pain management” was documented in 13.1% of total recordings. The mean daily methadone dose was 105.9mg (std 55.8mg). Both pain and satisfaction metrics were best for those on 60-119mg of methadone compared to those on lower or higher doses. A patient described both a partial value to split dosing as well as a strong preference for non-split dosing. This key informant’s experience will be further explored during presentation.

Discussion/conclusion: These data provide context to methadone-maintained inpatients who would be targeted for a future prospective study to test outcomes of split dosing. Overall, this OUD sample showed a high prevalence of moderate/severe pain and infrequently reported satisfaction with their pain management during admissions. If split dosing as an analgesic strategy is ultimately not found to have benefit among this population, inpatient recommendations can be simplified and focused on higher-yield interventions.



References:

Fishman, S. M., et al (2002). Methadone reincarnated: Novel clinical applications with related concerns. Pain Medicine (Malden, Mass.), 3(4), 339–348.

Smith, K., et al (2022). Pain Management Considerations in Patients With Opioid Use Disorder Requiring Critical Care. Journal of Clinical Pharmacology, 62(4), 449–462. https://doi.org/10.1002/jcph.1999

Veazie, S., et al (2020). Managing Acute Pain in Patients Taking Medication for Opioid Use Disorder: A Rapid Review. Journal of General Internal Medicine, 35(Suppl 3), 945–953.