A retrospective study of length of hospital stay in infants treated for neonatal abstinence syndrome with methadone versus oral morphine preparations.

PURPOSE: Length of hospital stay (LOS) of infants treated for neonatal abstinence syndrome (NAS) with methadone was compared to LOS of those treated with an oral morphine preparation (OMP, neonatal morphine solution, or deodorized tincture of opium).

METHODS: A retrospective review of medical records of infants treated for NAS due to in utero exposure to methadone and/or illicit drugs such as heroin or morphine was performed for birthweight, neonatal abstinence scores, infant and maternal illicit drug exposure history, maternal methadone dose (if any), and details of treatment. Length of stay was the primary outcome measure.

RESULTS: Forty-six infants met the inclusion criteria. The median LOS of infants treated with methadone versus OMP was not significant (P > 0.05). Prolonged LOS was associated with larger pharmacological treatment doses required to control withdrawal symptoms, larger maternal methadone dose, and increased birthweight. After adjusting for these factors, exposure to opioids in utero, maternal nicotine use, hospital of treatment, severity of withdrawal symptoms, and foster care placement were not significantly associated with LOS in univariate or multivariate analyses.

CONCLUSIONS: These results suggest that infants treated with OMP or methadone have similar LOS. Longer LOS is associated with both higher maternal methadone doses and higher opioid treatment dose requirements after birth. The potential effect of maternal methadone dose on neonatal LOS should be considered when treating expectant mothers on methadone maintenance therapy.