CEREBRAL OXYGENATION AND CEREBRAL BLOOD VOLUME DURING AMINOPHYLLINE TREATMENT IN PREMATURE NEWBORNS: QUANTITATIVE MEASUREMENT BY NEAR INFRARED SPECTROSCOPY

Aminophylline is commonly used for treatment of apnea and to permit weaning from ventilation in preterm newborns. Previous reports have indicated that it may cause cerebral vasoconstriction and reduction in cerebral blood flow (CBF) and cerebral blood volume (CBV). It is not known whether such reduction in CBF/CBV results in significant reduction in cerebral oxygenation. The purpose of this study was to evaluate the effect of aminophylline therapy on CBV and cerebral oxygenation using near infrared spectroscopy (NIRS Hamamatsu 500), Aminophyllinc (6.5 mg/kg) was given intravenously prior to weaning from the ventilator to 19 stable preterm infants (mean g.a.: 32 wks) with hyaline membrane disease. CBV, Hb diff (HbO2-Hb), deoxyhemoglobin (Hb) and cytochrome oxidase (CtO2) were measured using NIRS before and after aminophylline infusion. Continuous recordings of mean arterial pressure (MAP), tcpCO2 and tcpO2 were correlated with NIRS data. There was a marked fall in CBV after aminophylline infusion in 15 newborns with no significant reduction in tcpCO2. Despite reduction in CBV, cerebral oxygenation (HbD, CtO2) improved in stable preterm newborns.