Paediatrics: Neonatal abstinence syndrome

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 num-ber 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 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 drug of choice to treat barbiturate withdrawal).

Other points to consider are:

•   Does 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 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 relat-ed to drug exposure as literature is confounded by social and environmen-tal factors. There is an increased risk of:

•   prematurity;

•   IUGR;

•   sudden infant death syndrome (SIDS);

•   congenital HIV/hepatitis B/C infection;

•   social problems;

•   neurodevelopmental impairment.