Detection of neonatal intraventricular hemorrhage using transcephalic impedance

Transcephalic impedance (the resistance of the head to the flow of a 100 mu-amp alternating current) was measured serially during the first eight days of life in 93 neonates, ranging in gestational age from 26 to 43 weeks. Data compiled from the 70 clinically normal neonates showed an increase in mean trancephalic value with gestational age; this mean increase did not exceed 2.5 ohms during the first eight days of life within any four-week gestational age-group. Seven of the 23 clinically abnormal neonates showed evidence of clinical deterioration typical of intraventricular hemorrhage, and this diagnosis was confirmed at autopsy. Transcephalic impedance for these patients increased considerably with the onset of clinical deterioration, while the impedance for 11 clinically normal neonates, matched with these seven for gestational age, postnatal age and time of impedance measurement, rose only slightly. Transcephalic impedance is an uncomplicated, non-invasive, inexpensive test which has potential as a diagnostic aid in the detection of intraventricular hemorrhage.