Neonatal abstinence syndrome

Background

Incidence has quadrupled since 1999 from 1.5 per 1000 hospital births to 6.0 per 1000 in 2013^[1]
Condition caused by neonatal withdrawal from substance exposure in utero
- Withdrawal within first 24-48 hrs → fetal alcohol syndrome
- Withdrawal within 48-72 hrs → heroin
- Withdrawal at 7-14 days → methadone
Polysubstance withdrawal must also be considered

Pharmacologic treatment when 3 consecutive ≥ 8 on NAS(Finnegan scale
Enzyme immunoassay, urine toxicology, meconium analysis
Consider cranial ultrasound for cocaine-exposed neonates with abnormal neurologic signs

Supportive - swaddling to decrease sensory stimulation, frequent small feedings of 24 cal/oz formula
Opiates when supportive measures fail
Morphine is 1st line for infants exposed to both opioids and benzos
- Neonatal morphine 0.4mg/ml PO sln
  - Watch for side effect limiting dose (urinary retention)
  - Withdrawal symptoms need to be stabilized for 3-5 days before taper
  - Mother's methadone < 50mg (or other opiate)
    - Start morphine PO sln 0.1mg/kg q3hrs with feeds
    - Increase by 0.1mg/kg hourly if NAS score ≥ 8, max 1mg/kg
  - Mother's methadone > 50mg
    - Start 0.2mg/kg q3hrs
    - Increase by 0.2mg/kg hourly if NAS score ≥ 8, max 1mg/kg
- If NPO, use preservative free morphine at 50 mcg/ml
  - Load 30 mcg/kg over 1hr, then infusion at 2 mcg/kg/hr
  - Increase by 1 mcg/kg/hr hourly until NAS < 8, max 6 mcg/kg/hr
Benzo withdrawal treatment
- Midazolam 0.1mg/kg IV q3hrs or 0.3mg/kg PO q3hrs
- OR phenobarbital 3mg/kg IV or PO q24hrs
Phenobarbital for seizures OR side effect limiting morphine effects OR max morphine dose reached
- 16mg/kg load divided into two consecutive feedings for day 1
- 24 hrs later, use 2-8mg/kg/day maintenance dose

↑ Ko JY et al. Incidence of Neonatal Abstinence Syndrome — 28 States, 1999–2013. Weekly / August 12, 2016 / 65(31);799–802.

Hudak ML, Tan RC. Neonatal Drug Withdrawal. Pediatrics. January 2012. 129(2):e540-560.
Lainwala S, Brown ER, Weinschenk NP, Blackwell MT, Hagadorn JI. A retrospective study of length of hospital stay in infants treated for neonatal abstinence syndrome with methadone versus oral morphine preparations. Adv Neonatal Care. 2005 Oct. 5(5):265-72.
Hall ES, Wexelblatt SL, Crowley M, Grow JL, Jasin LR, Klebanoff MA, et al. A multicenter cohort study of treatments and hospital outcomes in neonatal abstinence syndrome. Pediatrics. 2014 Aug. 134(2):e527-34.
Pullen L. Neonatal Abstinence Syndrome: Stringent Weaning Protocol Best. Available at http://www.medscape.com/viewarticle/829115. Accessed: August 12, 2016.