Iatrogenic Opiate Withdrawal in Pediatric Patients: Implementation of a Standardized Methadone Weaning Protocol and Withdrawal Assessment Tool

Abstract

Methadone is frequently used to prevent withdrawal symptoms secondary to intended therapeutic opiate exposure. Absence of a standardized dose weaning strategy potentially results in increased exposure to narcotics and/or withdrawal symptoms. We sought to quantify the effect of implementing a standardized methadone weaning protocol and withdrawal assessment tool on methadone exposure and opiate withdrawal in pediatric patients receiving 5 or more days of continuous morphine or fentanyl infusions. The preintervention phase included patients weaned off of opiate infusions before implementation of a standardized weaning protocol and withdrawal symptom scoring tool. Patients in the postintervention phase were started on a standardized methadone wean based on total duration and dose of continuous opiate infusion exposure in the 24 hours preceding methadone initiation. Patients received either a 5- or 10-day wean, with the total daily methadone dose reduced by 20% daily or every other day, respectively. Patients in the postintervention phase were monitored for withdrawal using the withdrawal assessment tool (WAT-1). Postintervention patients were compared to preintervention patients treated with methadone. Total methadone duration decreased significantly from a median of 17 (13-22 interquartile range [IQR]) to 5 (5-10 IQR) days (P = .00001) after implementation of the methadone weaning protocol. Number of morphine boluses administered increased from a median of 3 (0-6 IQR) to 4 (0-5 IQR) doses per patient (P = .45). Demographic data were similar between both groups. Patients in the postintervention phase had significant reductions in methadone exposure after implementation of a standardized methadone weaning protocol and assessment tool.