Measurements of Cerebral Blood Flow Velocity Change Using Color Doppler in Asphyxiated Infants

ABSTRACT

PURPOSE: Alterations in cerebral blood flow are very important for understanding the neurological consequences of all varieties of perinatal asphyxia. The purpose of this study is to measure the change of cerebral blood flow velocity and resistance index (RI) of middle cerebral artery (MCA) according to the time in asphyxiated infants. METHODS: We studied 7 asphyxiated term infant and 27 normal term infant who were born at Ewha Womans University Hospital from January 1996 to August 1997. Using the Doppler ultrasound, we examined blood flow velocity and RI of the middle cerebral artery. RESULTS: Clinical characteristics were not significantly different in both groups. Peak systolic flow velocity (PSFV) in asphyxiated infants significantly decreased than control (P<0.05). End diastolic flow velocity (EDFV) was not significantly different in both groups. RI in asphyxiated infants significantly decreased for 24 hours (P<0.05). No control infant ever had a RI value of 0.55 or below, three (42.9%) asphyxiated infants had a RI value of 0.55 or below. The changes of the systemic BP and heart rate were not significant. Two (28.6%) asphyxiated infants were proven periventricular white matter ischemia by ultrasonography. CONCLUSION: It is therefore very important to monitor RI in asphyxiated infants even if the degree of asphyxia is mild.