Cocaine Exposure
In-utero cocaine exposure is also associated with neurobehavioral abnormalities in neonates although a withdrawal syndrome is less clearly defined. Findings, however, are consistent with NAS and include increased irritability, tremors, and high-pitched cry—most frequently occurring between 24 and 48 hours postdelivery.6
Neonatal Alcohol Withdrawal Syndrome
Neonatal alcohol withdrawal syndrome, particularly in fetuses exposed to alcohol during the last trimester, is distinct from fetal alcohol syndrome (FAS). The latter is associated with typical dysmorphic features, growth deficiencies, and CNS findings reflective of permanent neurologic sequelae. Neonatal alcohol withdrawal presents with CNS findings similar to those listed for other in-utero exposures—eg, increased irritability, tremors, nystagmus hyperactive reflexes.7
Screening for NAS: The Finnegan Scale
Figure
The Finnegan Neonatal Abstinence Scoring System is one of the most commonly employed and validated tools used to screen for NAS. It comprises a 31-item scale, listing the clinical signs and symptoms of NAS, which are scored by severity and organized by system to include neurologic, metabolic, vasomotor, respiratory, and GI disturbances (Figure). Point allocation is based on mild, moderate, or severe symptoms as follows:
- Mild findings (eg, sweating, fever <101°F mottling, nasal stuffiness) each score 1 point.
- Moderate findings (eg, high-pitched cry, hyperactive moro reflex, increased muscle tone, fever >101°F, increased RR >60 with retractions, poor feeding, loose stools) each score 2 points.
- Severe findings (eg, myoclonic jerks, generalized convulsions, projectile vomiting, watery stools) each score 3 points.
While each of the above are independently nonspecific, the constellation of findings, together with the appropriate history, provide for a clinical diagnosis. The Finnegan Scale is therefore designed not only to aid in diagnosis, but also to quantify the severity of NAS and guide management.
Screening for NAS begins at birth in neonates with known in-utero exposure (ie, when risk of NAS is high) or at the time of initial presentation in other circumstances. Scoring is performed every 4 hours; the first two or three scores will determine the need for pharmacotherapy (see Table).
| Table |
Pharmacotherapy is indicated in the following Finnegan scoring scenarios: |
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How is NAS treated?
The two main goals of management in the treatment of opioid-related NAS are to relieve the signs and symptoms of withdrawal and to prevent complications (eg, fever, weight loss, seizures). Therapy should begin with nonpharmacologic measures that minimize excess external stimuli, such as swaddling, gentle handling, and minimizing noise and light. To prevent weight loss, small hypercaloric feeds may be helpful. If pharmacologic treatment is indicated, oral opioid replacement with morphine is considered by many to be the drug of choice. Oral morphine dosing may be guided by NAS severity based on the Finnegan score; alternatively, initial dosing at 0.1 mg/kg orally every 4 hours has also been recommended.1
Other agents, such methadone 0.1 mg/kg orally every 12 hours and buprenorphine 15.9 mcg/kg divided in three doses orally, may also be used. In patients whose symptoms persist despite opioid treatment, use of adjuncts such as phenobarbital and clonidine may be indicated.
Case Conclusion
The patient was admitted to the neonatal intensive care unit where she appropriately underwent a sepsis workup. Laboratory evaluation, including blood and urine cultures, was obtained. A brain ultrasound was unremarkable, and since lumbar puncture was unsuccessful, the patient was started empirically on meningitis doses of the cefotaxime, vancomycin, and acyclovir.
An initial Finnegan score was calculated. With the exception of soft stools, there were no other persistent symptoms, and patient did not achieve a score indicating a need for pharmacologic management. After 48 hours, she remained afebrile and soft stools resolved. All laboratory values, including cultures, were unremarkable. The patient was discharged on hospital day 3, with a scheduled well-baby follow-up appointment.
Dr Laskowski is a medical toxicology fellow in the department of emergency medicine at New York University Langone Medical Center. Dr Nelson, editor of "Case Studies in Toxicology," is a professor in the department of emergency medicine and director of the medical toxicology fellowship program at the New York University School of Medicine and the New York City Poison Control Center. He is also associate editor, toxicology, of the EMERGENCY MEDICINE editorial board.