Transcephalic impedance in the neonate: an indicator of intracranial hemorrhage, asphyxia, and delayed maturation.

Increased transcephalic impedance readings (greater than 3 SD) were recorded in 13 asphyxiated infants 35 weeks or more in gestation, and in 13 preterm infants 34 weeks or less in gestation and with intracranial hemorrhage (greater than 2 SD). Six infants had decreased TCZ recordings in the weeks following intracranial hemorrhage, without ultrasound evidence of ventricular enlargement. TCZ provides quick, inexpensive, noninvasive indication of tissue necrosis, moderate-to-severe intracranial hemorrhage, and delayed brain maturation.