Normative Values of Cerebral Blood Flow Velocities in Very Low Birth Weight Neonates During First 28 Days of Life.

Objective: To determine the normative values of cerebral blood flow (CBF) velocities in very low birth weight (VLBW) neonates during the first 28 days of life.

Method: In this prospective observational study, doppler assessment of CBF velocities was performed from the anterior cerebral artery (ACA), middle cerebral artery (MCA) and basilar artery (BA) at 2-8 hours, 24 hours, day 3, 7, 14 and 28 of life. Neonates with gross congenital malformations, those requiring extensive resuscitation at birth, mechanical ventilation with mean airway pressure >12 mbar, requiring inotropes, or those who developed intraventricular hemorrhage (grade II or more) were excluded.

Results: A total of 103 VLBW neonates were enrolled, in whom 1178 doppler measurements were recorded. The mean (SD) peak systolic velocity, end diastolic velocity and mean velocity (cm/s) in ACA increased from 26.53 (8.56) to 51.35 (9.36), 9.22 (2.91) to 13.9 (3.24) and 17.75 (3.97) to 25.84 (3.27) respectively from 2 to 8 hours to day 28 of life. In MCA and BA also, CBF velocities increased with post-natal age.

Conclusion: We report normative data of CBF velocities in VLBW neonates in first 28 days of life.