Finnegan Score For Neonatal Abstinence Syndrome (NAS) Calculator

How does thIS Finnegan score for neonatal abstinence syndrome (NAS) calculator work?

This health tool quantifies the severity of NAS and helps in monitoring and determining the right route of treatment. The Finnegan score for neonatal abstinence syndrome (NAS) calculator consists of 31 items portraying symptoms significant with NAS and allows nursery staff to monitor infants at risk.

Neonatal abstinence syndrome occurs in infants that have been exposed to drugs during gestation and is caused by the abrupt cessation of drug exposure due to birth.

Most common NASs are caused by opioid exposure followed by sedative, barbiturates and alcohol exposure.

The main infant signs of withdrawal at NCS level include: irritability, increased wakefulness, tremor, muscle tone, reflex hyperactivity or seizures. Gastrointestinal symptoms include vomiting, dehydration, diarrhea, poor feeding and uncoordinated sucking.

Onset for opioid exposed infants occurs within 24-36 hours after birth but can also be delayed up to a week, that of alcohol exposure is shorter at only 3 to 12 hours while sedative exposure withdrawal occurs after 1-3 days.

The following presents the criteria in the Finnegan score calculator, the points each are awarded and some items also benefit from extra explanations.

1) Central Nervous System:

■ Excessive high pitched (or other) cry (<5 min) [+2] - The infant is described as unable to use self consoling measures and is only calmed with exterior intervention for short durations of time;

■ Continuous high pitched (or other) cry (>5 min) [+3] - The infant cries intermittently or continuously for more than 5 minutes regardless of consoling measures;

■ Sleep <1 hour after feeding [+3] - Sleep scoring needs to be based on the longest period of sleep displayed since monitoring has started;

■ Sleep <2 hours after feeding [+2];

■ Sleep <3 hours after feeding [+1];

■ Hyperactive Moro reflex [+2] - The infant exhibits jitteriness and sustained clonus of the hands and/or arms during or after a Moro reflex;

■ Moderately hyperactive Moro reflex [+3] - The infant exhibits pronounced jitteriness of the hands;

■ Mild tremors when disturbed [+1] - Tremors of one or both hands / feet while being handled or disturbed;

■ Moderate-severe tremors when disturbed [+2] - Tremors of arms / legs while being handled or disturbed;

■ Mild tremors when undisturbed [+3] - Tremors of one or both hands / feet when not being handled;

■ Moderate-severe tremors when undisturbed [+4] - Tremors of arms / legs when not being handled;

■ Increased muscle tone [+1] - Revealed by no head lag, total body rigidity or tight flexion of arms and legs;

■ Excoriation (eg. Chin, knees, elbows, toes, nose) [+1] - Present skin irritation unrelated to diaper rash;

■ Myclonic jerks (twitching/jerking of limbs) [+3] - Infant exhibits twitching movements of face or extremities muscles;

■ Generalized convulsions [+5].

2) Metabolism, Vasomotor, Respiratory:

■ Sweating [+1];

■ Hyperthermia (37.2 – 38.2°C) [+1];

■ Hyperthermia (=38.4°C) [+2];

■ Frequent yawning [+1] - Present more than 3/4 times during one evaluation;

■ Molting [+1];

■ Nasal stuffiness [+1];

■ Frequent sneezing (>3-4/interval) [+1];

■ Nasal flaring [+2];

■ Respiratory rate >60/min [+1];

■ Respiratory rate >60/min with retractions [+2].

3) Gastrointestinal:

■ Excessive sucking [+1] - Infant exhibits rooting more than 3 times during evaluation plus shows swiping movements with hand across mouth;

■ Poor feeding (infrequent/uncoordinated suck) [+2] - The infant stops frequently to breathe;

■ Regurgitation (=2 times during/past feed) [+2];

■ Projectile vomiting [+3];

■ Loose stool [+2];

■ Watery stool [+3].

The main criticism received is that the scale is too complex and can be timely for routine use. However, due to its comprehensiveness is often preferred in clinical practice and referenced in studies.

There are other scores of severity developed for full term infants suffering from withdrawal syndrome. One of them is the Neonatal Withdrawal Inventory which consists of 7 NAS symptoms and a 4 point behavioral scale. Another example is the Neonatal Narcotic Withdrawal Index consisting of 18 symptoms, each weighted on a scale from 0 to 2 with a cut off for pharmacotherapy at 5 points.

NAS Score interpretation

The Finnegan Neonatal Abstinence Scoring System consists of 31 items evaluating symptoms, each with a specific weighing.

The score needs to be applied every 4 hours during admission for scores below 8 and every 2 hours for scores of 8 and greater which usually require pharmacological therapy as well.

Medication is instituted when scores above 8 are obtained in at least 2 consecutive evaluations and is meant to stabilize the more severely symptomatic infants and being only temporary until the withdrawal symptoms recede.

Since some of the items in the scale can be presented in infants due to other conditions or simply unrelated to NAS in their case, often the score can be adjusted by removing the points awarded for those symptoms.

References

1) Jansson LM, Velez M, Harrow C. (2009) The Opioid Exposed Newborn: Assessment and Pharmacologic Management. J Opioid Manag; 5(1): 47–55.

2) American Academy of Pediatrics Committee on Drugs. (2012) Neonatal Drug Withdrawal. Pediatrics 2012; 129; e540.

3) Siu A, Robinson CA. (2014) Neonatal Abstinence Syndrome: Essentials for the Practitioner. J Pediatr Pharmacol Ther; 19(3): 147–155.

4) Bio LL, Siu A, Poon CY. (2011) Update on the pharmacologic management of neonatal abstinence syndrome. Journal of Perinatology; 31, 692-701.