Relationship of pneumothorax to occurrence of intraventricular hemorrhage in the premature newborn.

The relationship of pneumothorax to the occurrence of intraventricular hemorrhage (IVH) has been studied in the premature newborn. The major objective of the study was to determine whether the systemic hemodynamic changes that occur with pneumothorax are reflected in the cerebral circulation and whether these changes play a role in pathogenesis of IVH. Blood flow velocity was measured in the anterior cerebral arteries by a transcutaneous Doppler technique in nine infants who developed pneumothorax in the first 3 days of life. At the time of pneumothorax there was a marked increase in flow velocity, especially during diastole, and, with resolution of pneumothorax, flow velocity returned to normal levels over the ensuing hours. The changes in flow velocity correlated closely with systemic hemodynamic changes that occurred with pneumothorax, ie, and increase in mean systemic blood pressure, especially diastolic pressure. IVH, documented by serial ultrasound scans, was observed shortly after pneumothorax in the nine infants. The data thus demonstrate a marked increase in flow velocity in the cerebral circulation at the time of pneumothorax. This increase is of importance in the genesis of IVH as is suggested further by the occurrence of IVH soon after the cerebral hemodynamic changes.