Comparison of middle component potentials of preterm infants with preterm infants who had intraventricular hemorrhage.

Fifteen preterm infants in the Newborn Intensive Care Unit, University of Utah Medical Center, were studied in an attempt to describe the middle component response (8-50 msec post-stimulus) of the auditory evoked potentials. Five of the preterm infants had intraventricular hemorrhage (IVH) without severe birth asphyxia. Their middle component response was compared with the middle component response of ten preterm infants who did not have IVH or severe birth asphyxia (Group II). The middle component responses of these two groups were elicited by both click and tone stimuli. Both groups were tested after 34 weeks of age by birth dates while they were observed as being asleep. The middle component responses, peaks Po, Na, Pa, and NB, were described according to mean, range, and standard deviation. There was no significant statistical difference between the middle component response of the preterm infant with IVH compared with the preterm infant without IVH using paired t-test analysis. It was aw subjective finding of the study that the tone pip stimuli elicited a “clearer†response than did the click stimuli. The investigator concluded that there was no significant statistical difference between the middle component response of preterm infants with IVH and preterm infants without IVH. It is recommended by the investigator that a larger sample be obtained to study the middle component response more extensively in preterm infants.