Neurologic manifestations of in utero cocaine exposure in near-term and term infants

Abstract

Objective: To determine whether the incidence of neurosonographic and neurologic abnormalities is higher in cocaine-exposed infants at birth.

Methods: In utero exposure to cocaine was investigated in 39 term and near-term infants with positive urine screens for cocaine only and 39 matched control infants without drug exposure admitted to the regular term newborn nursery. Serial evaluations were performed on each infant on postnatal days 1 and 2 and included a cranial sonogram, a neurologic and behavioral assessment for drug withdrawal, and Doppler interrogation of the anterior and middle cerebral arteries.

Results: There were no differences between groups in neurosonographic abnormalities. Grade I or II intraventricular hemorrhage occurred in 11% of cocaine-exposed and 11% of control infants. There were no cases of grade III intraventricular hemorrhage, cystic periventricular leukomalacia, or neonatal stroke. Head size was smaller in cocaine-exposed infants, ie, 32.7 +/- 0.1 cm versus 33.8 +/- 0.1 cm. The neurologic examination was similar between groups with regard to tone, reflexes, and cranial nerves. Behavioral scores were higher on both days, in cocaine-exposed versus control infants, ie, 4.4 +/- 0.5 versus 2.7 +/- 0.03 on day 1 and 5.0 +/- 0.5 versus 1.71 +/- 0.31 on day 2. Cerebral blood flow velocity measurements in the anterior cerebral artery were similar between groups on both days of examination. However, cocaine-exposed infants demonstrated a significant increase in flow velocity from day 1 to day 2, ie, 0.48 +/- 0.03 to 0.57 +/- 0.04. There was a concomitant decrease in the pulsatility index from day 1 to day 2 in the cocaine-exposed, ie, 0.74 +/- 0.02 to 0.69 +/- 0.02, but not in the control infants. No differences were noted in the flow velocities in the middle cerebral arteries between groups.

Conclusions: Term and near-term infants admitted to a regular nursery who are exposed to cocaine in utero: (1) do not exhibit an increased incidence of neurosonographic abnormalities; (2) do exhibit altered behavior consistent with drug withdrawal; and (3) do demonstrate changes in flow velocity in the anterior cerebral artery consistent with the vasoconstrictive effects of the drug. However, these changes were not accompanied by changes in the neurologic examination or altered care. The long-term neurodevelopmental implications of these subtle abnormalities in the neonatal period remain to be determined.