Paediatrics: Neonatal abstinence syndrome

2021-03-05 12:00 AM

A cluster of symptoms caused by withdrawal from a dependency-inducing substance.

Neonatal abstinence syndrome

A cluster of symptoms caused by withdrawal from a dependency-inducing substance. In the UK this is commonly related to methadone (+/– heroin), or benzodiazepines, however, withdrawal is well documented with a number of other substances, for example; cocaine, amphetamine, SSRIs (e.g. fluoxetine), alcohol, caffeine, and nicotine.

Presentation

  • Timing depends on substance: heroin and SSRIs often present soon after birth, methadone within 24hr, and benzodiazepines later.
  • CNS symptoms: include irritability, sleepiness, hyperactivity, tremors, seizures.
  • Non-CNS: poor/disorganized feeding, vomiting, diarrhoea (can cause a severe nappy rash), sneezing, tachycardia, sweating, respiratory depression, fever (be cautious—sepsis may co-exist or present with similar symptoms).

Management

  • Observe ‘at risk’ infants for signs of withdrawal for several days after birth. Several scoring systems exist for quantifying withdrawal.
  • General and supportive measures: swaddling, minimal handling, dark and quiet environment, frequent low volume feeding.
  • A pragmatic approach to starting drug treatment (low dose oral morphine) would be to start if significantly symptomatic,e.g. sleeping <1hr after feeds, continuous high-pitched cry, unable to feed. Once stable, wean morphine slowly over several days.
  • Start apnoea monitor if preterm or require large doses of morphine.
  • Seizures should be controlled by phenobarbital (also a drug of choice to treat barbiturate withdrawal).

Other points to consider are:

  • Does the baby need a urine screen (remember this will effectively drug-test the mother)?
  • Ensure Social Services are aware as child protection and family support issues must be considered.
  • Consider associated pathologies, e.g. HIV or hepatitis B or C infection.
  • Breastfeeding is not contraindicated unless the mother is taking high doses of methadone (>20mg/day), amphetamines, cocaine, or is HIV +ve.

Prognosis

It is difficult to establish whether any adverse outcomes are directly related to drug exposure as literature is confounded by social and environmental factors. There is an increased risk of:

  • prematurity;
  • IUGR;
  • sudden infant death syndrome (SIDS);
  • congenital HIV/hepatitis B/C infection;
  • social problems;
  • neurodevelopmental impairment.