Abstract
To define the associated cerebrovascular hemodynamic alterations in neonatal asphyxia, the anterior cerebral arteries (ACA) and the internal cerebral veins (ICV) were examined by Doppler ultrasound in 12 term asphyxiated and 22 control infants. In the control infants, the cerebral blood flow velocities in both ACA and ICV increased gradually in the first month of life. There were no significant differences in the blood flow velocities between the control and asphyxiated infants without major neurological impairment. On the other hand, in all asphyxiated infants with major neurological impairment, abnormally high blood flow velocities in ACA and ICV (>+3 SD above the means for the control infants) and an abnormally low index of cerebral circulatory resistance (RI) values (<0.55) were observed within a few days after birth, and thereafter the blood flow velocities decreased during the first month. In conclusion, the high blood flow velocities in ACA and ICV, and the low RI values within a few days after birth, and the decrease in the blood velocities during the first month may be considered as signs of a grave prognosis for future neurological development in asphyxiated infants.
