Neonatal abstinence and withdrawal syndromes — formative SAQs

SAQ 1 — The methadone-exposed infant at 48 hours (10 marks)

A 36-week infant whose mother is on a supervised methadone maintenance programme (90 mg/day, stable, HIV-negative, non-smoker) has been rooming-in and breastfeeding since birth. At 48 hours of life the infant has a high-pitched cry, a fine tremor when handled, sweating, a stuffy nose and poor feeding; the bedside glucose is 2.2 mmol/L. [3]

a) Explain the neuroadaptive mechanism by which methadone produces neonatal withdrawal, and state why it peaks at 48–72 hours. (3 marks) [3]

Chronic in-utero opioid exposure suppresses the locus coeruleus and dampens neuronal firing at the μ-opioid receptor; the fetal brain compensates by up-regulating μ-receptor density and raising the tonic activity of noradrenergic and dopaminergic pathways so that it can keep firing in the presence of the drug. When the cord is clamped the methadone supply ceases abruptly, but the compensatory up-regulation persists, and the unopposed surge of CNS and autonomic activity produces the triad of CNS hyperexcitability, autonomic overdrive and gastrointestinal dysregulation. Methadone has a long half-life, so the withdrawal characteristically peaks at 48–72 hours — later than short-acting opioids — which is why methadone-exposed infants are observed in hospital for at least 5–7 days. [3]

b) Apply the Eat, Sleep, Console functional assessment to this infant, and state the treatment decision it drives. (2 marks) [7]

The three functional questions are whether the infant can eat at least one ounce per feed, sleep at least one hour, and be consoled within ten minutes. This infant is taking only a fraction of the expected volume (eat goal failing) and has fractured sleep (sleep goal failing), so the functional assessment indicates that the infant is not meeting the goals. The decision flow is to intensify non-pharmacologic care first — low stimulation, swaddling, skin-to-skin, lactation support — and to reach for morphine or buprenorphine only if the infant still cannot eat, sleep or be consoled despite that. [7]

c) Give your immediate management, including the metabolic priority. (3 marks) [3]

The metabolic priority is to correct the hypoglycaemia: give a dextrose bolus (typically 2 mL/kg of 10% dextrose) followed by a continuous infusion, and recheck the glucose. Exclude the mimics by checking electrolytes (calcium, magnesium) and performing a septic screen if the infant is unwell. Intensify the non-pharmacologic bundle — continue rooming-in and demand breastfeeding (the mother is stable, HIV-negative and on supervised methadone, so breastfeeding is endorsed and protective), maintain a low-stimulation environment, swaddle and offer skin-to-skin contact. Escalate to first-line pharmacotherapy (oral morphine or sublingual buprenorphine) only if the infant fails to meet the functional goals despite maximal conservative care. [3] [9]

d) Compare oral morphine with sublingual buprenorphine as first-line pharmacotherapy, citing the evidence. (2 marks) [6]

Oral morphine is the long-standing first line: it is started at a defined initial dose (typically 0.05 mg/kg/dose every 3–4 hours) and titrated upward in set increments until the infant is settled and feeding. Sublingual buprenorphine is the evidence-based alternative; the Kraft NEJM 2017 randomised trial showed that buprenorphine shortened the duration of treatment and length of stay relative to morphine. Buprenorphine requires an extemporaneous preparation and attention to its complex pharmacology, but it offers a faster wean. Once stable for 24–48 hours, the opioid is weaned by 10–20 percent daily. Phenobarbital should not be used as a sole agent for pure opioid withdrawal. [6] [3]

SAQ 2 — Assessment paradigms, breastfeeding and the wean (10 marks)

An opioid-exposed infant on the neonatal unit has been assessed with the Modified Finnegan Neonatal Abstinence Scoring System. Three consecutive 3-hourly scores total 26, 28 and 27. [1]

a) State the Finnegan NASS treatment threshold and explain why three consecutive elevated scores, rather than a single score, are used. (2 marks) [1]

The Modified Finnegan NASS is a 21-item weighted instrument across CNS, autonomic and gastrointestinal domains, scored every 3–4 hours. The traditional threshold to begin pharmacotherapy is a single score of 8 or more, or three consecutive scores totalling 24 or more. Three consecutive scores are used to distinguish sustained withdrawal from transient irritability (for example, from hunger, a wet nappy or a procedural disturbance), and to capture the trend that confirms the need for treatment. The three scores of 26, 28 and 27 exceed the consecutive-score threshold and indicate pharmacotherapy is warranted. [1]

b) Describe the Eat, Sleep, Console paradigm and explain why it was developed as an alternative to a purely score-driven approach. (3 marks) [7]

Eat, Sleep, Console reframes assessment around three functional goals assessed at every feed: can the infant eat at least one ounce, sleep at least one hour, and be consoled within ten minutes? If all three goals are met, the infant needs no medication regardless of the score; if not, non-pharmacologic care is intensified first and a PRN dose of morphine is given only when that fails. Grossman argued that the purely score-driven approach over-treats infants who are functionally well — an infant with a high score who is feeding, sleeping and settling does not need an opioid — and quality-improvement work (Blount) showed that ESC substantially reduced both length of stay and morphine exposure. [7]

c) Summarise the evidence that breastfeeding reduces the need for pharmacotherapy, and state the conditions under which it is endorsed. (3 marks) [9]

The Welle-Strand cohort showed that breastfeeding substantially reduced the proportion of opioid-exposed infants needing withdrawal treatment, and the Academy of Breastfeeding Medicine protocol endorses breastfeeding in stable mothers on opioid agonist therapy. The mechanism is both behavioural — close contact, demand feeding and settling — and pharmacologic, as small amounts of opioid transfer through milk smooth the decline in drug exposure. Breastfeeding is endorsed when the mother is stable on supervised methadone or buprenorphine, is HIV-negative, and has no other contraindication (such as illicit opioid use or specific contraindicated substances). The decision to stop breastfeeding should be deliberate, not abrupt, as sudden cessation can precipitate or worsen infant withdrawal. [9]

d) Outline the weaning strategy once first-line pharmacotherapy has stabilised the infant. (2 marks) [3]

Once the infant is stable — calm, feeding and sleeping — for 24–48 hours, the opioid dose is weaned by 10–20 percent of the total daily dose each day. The wean is guided by the ongoing assessment (Finnegan scores or functional goals), and slowed if signs recur. Discharge is appropriate when the wean is complete (or a safe, stable low-dose home wean is feasible with close support), feeding and weight gain are established, and the plan of safe care — maternal treatment, child protection, safe sleep and follow-up — is in place. [3]