Does caffeine impair cerebral oxygenation and blood flow velocity in preterm infants?

Aim: The aim of the study is to assess the effects of an intravenous 10 mg/kg loading dose of caffeine base in cerebral oxygenation, cerebral Doppler blood flow velocity and cardiac output in preterm infants. Methods: Preterm neonates < 34 weeks gestation were investigated at 1 and 4 h following the loading dose of caffeine using Doppler cerebral sonography, cardiac echocardiography and cerebral spatially resolved near-infrared spectroscopy. Results: Forty infants were studied with a mean gestational age (mean +/- standard deviation) of 27.7 (+/- 2.5) weeks, birth weight of 1155 (+/- 431) g and a postnatal age of 2.8 (+/- 2.2) days. Mean Anterior Cerebral Artery peak and time average mean blood flow velocity fell significantly by 14% and 17.7%, respectively at 1 h post-caffeine loading dose, which recovered partially by 4 h. Cerebral Tissue Oxygenation Index fell from pre-dose levels by 9.5% at 1 h with partial recovery to 4.9% reduced at 4 h post-dose. There were no significant changes in left or right ventricular output, transcutaneous oxygen saturation, transcutaneous PCO(2) or total vascular resistance. Conclusions: A loading dose of 10 mg/kg caffeine base resulted in significant reduction at 1 h post-dose in cerebral oxygenation and cerebral blood flow velocity with partial recovery at 4 h.