Finnegan NAS

Overview

Neonatal opioid withdrawal syndrome (NOWS) — formerly neonatal abstinence syndrome (NAS) — occurs in infants born to mothers who used opioids during pregnancy. Finnegan and colleagues first published a structured withdrawal-severity scale in 1975 ^[1]; the version implemented in Scores2Go is the commonly used 21-item modification, scored 0–46, and organized into three domains: central nervous system (CNS), metabolic/vasomotor/respiratory (MVR), and gastrointestinal (GI).

Scores are typically performed every 3–4 hours or after each feeding in the first days of life. A rising trend over consecutive assessments — not a single elevated score — is what informs treatment decisions (see Score Interpretation below).

CNS Domain

Metabolic / Vasomotor / Respiratory (MVR) Domain

Gastrointestinal (GI) Domain

Score Interpretation

21 items, maximum score 46.

Clinical Notes

• Assess every 3–4 hours after each feeding for at least the first 5 days of life in at-risk neonates.
• Pharmacotherapy is typically initiated after three consecutive scores ≥ 8, or two consecutive scores ≥ 12 ^[3] — not from a single isolated score.
• Breastfeeding (unless contraindicated) and rooming-in are recommended as first-line non-pharmacological measures.
• Eat, Sleep, Console (ESC) is an emerging function-based alternative that has been shown to reduce pharmacotherapy use and length of stay (see Scientific Validity & Limitations).

Scientific Validity & Limitations

The original Finnegan scale was derived from observations of 55 term infants of heroin-dependent mothers at a single centre in the 1970s ^[1], and it has never been formally validated in preterm infants, in whom several signs (tone, tremor, sucking) are confounded by gestational immaturity independent of withdrawal.

The tool's items — cry quality, tremor severity, mottling — require substantial clinical judgement, and poor inter-rater reliability between examiners has long been recognised as a practical limitation of Finnegan-family scores, complicating both bedside comparability and use as a research outcome measure.

The widely used ≥ 8 threshold is a statistical "how abnormal is abnormal" cutoff, not an outcome-validated treatment threshold. It derives from the observation that non-opioid-exposed, healthy infants' 95th-percentile score does not exceed 8 in the first three days of life ^[2] — i.e. it defines an upper bound of normal in unexposed infants, not a threshold shown by trial evidence to identify the exposed infants who most benefit from pharmacotherapy. No randomised trial has directly compared different score thresholds for initiating treatment.

Withdrawal severity and treatment duration are also known to vary by which opioid the mother was exposed to: in the MOTHER trial, infants exposed to buprenorphine required significantly less morphine and a shorter hospital stay than those exposed to methadone, despite similar NAS incidence between groups ^[4] — a source of variability the Finnegan score itself does not capture.

Practically, the 21-item scale performed every 3–4 hours around the clock is a substantial nursing burden, and its subjective, sign-counting design has motivated function-based alternatives. Eat, Sleep, Console (ESC) assesses whether an infant can eat adequately, sleep undisturbed, and be consoled, rather than counting discrete signs; quality-improvement studies applying ESC have reported markedly shorter hospital stays and substantially lower rates of pharmacological treatment without an increase in adverse safety outcomes, compared with historical Finnegan-based management ^[5][6].

The Finnegan tool was not the only withdrawal scale proposed in the mid-1970s: Lipsitz published a simpler alternative narcotic withdrawal score the same year ^[7], though it never achieved the same widespread adoption.

Literature

1. Finnegan LP, Connaughton JF Jr, Kron RE, Emich JP. Neonatal abstinence syndrome: assessment and management. Addict Dis. 1975;2(1-2):141–158.
2. Zimmermann-Baer U, Nötzli U, Rentsch K, Bucher HU. Finnegan neonatal abstinence scoring system: normal values for first 3 days and weeks 5–6 in non-addicted infants. Addiction. 2010;105(3):524–528.
3. Hudak ML, Tan RC; Committee on Drugs; Committee on Fetus and Newborn; American Academy of Pediatrics. Neonatal drug withdrawal. Pediatrics. 2012;129(2):e540–e561.
4. Jones HE, Kaltenbach K, Heil SH, et al. Neonatal abstinence syndrome after methadone or buprenorphine exposure. N Engl J Med. 2010;363(24):2320–2331.
5. Grossman MR, Berkwitt AK, Osborn RR, et al. An initiative to improve the quality of care of infants with neonatal abstinence syndrome. Pediatrics. 2017;139(6):e20163360.
6. Grossman MR, Lipshaw MJ, Osborn RR, Berkwitt AK. A novel approach to assessing infants with neonatal abstinence syndrome. Hosp Pediatr. 2018;8(1):1–6.
7. Lipsitz PJ. A proposed narcotic withdrawal score for use with newborn infants. Clin Pediatr. 1975;14(6):592–594.