Analysis The Hemodynamic Changes Of Middle Cerebral Artery In Premature Infant With Intraventricular Hemorrhage By Color Doppler Ultrasound

Objective:To evaluate the hemodynamics of middle cerebral artery (MCA) and influence of gestation age(GA),birth weight(BW),age and mean arterial blood pressure(MABP) in premature infants with intraventricular hemorrhage(IVH).Methods:We detected the hemodynamics of MCA in 110 premature infants by color Doppler ultrasound,and divided into three groups according to their brain's sonographic:control group (45 cases), mild IVH group (45 cases) and severe IVH group (20 cases).Results:1.The correlation between IVH and GA,BW was demonstrated. The lower the GA and BW were,the higher the incidence of IVH would be,and the hemorrhage tended towards serious. There was a wider range of fluctuation of blood pressure in the premature with IVH.2.In healthy infants, there was a liner increase velocities and Vd of MCA with increasing GA and BW. Correlation coefficients of the Vs,Vd in MCA and GA and BW were 0.57,0.42,0.74,0.55 (P<0.05).There were linear decrease of Vs with MABP,the correlation coefficients of the Vs in MCA and MABP were 0.73,0.86(P<0.05) in mild and severe IVH.3. Within 1 week,there was a linear increase of all velocities of MCA with increasing age. Mild IVH in preterm infants with MCA in the third day of postnatal were obviously faster than in control group (P＜0.05). The Vs of serious IVH group decreased significantly in the first day compared with those of control group and mild group(P<0.05). The Vs of serious IVH group decreased significantly in the seventh day compared with those of mild (P＜0.05).Conclusion:In healthy infants, there was a liner increase velocities and vd of MCA with increasing GA,BW and age, when Cerebral blood flow was evaluated, it was very important to pay attention to BW, GA and age.There were impaired cerebrovascular autoregulation within 24 hours after birth in premature infants with IVH, whose Vs of MCA had linear relationship between with MABP. Therefore, two-dimensional ultrasound combined with color Doppler ultrasound were applied to monitor the intracranial lesions and the cerebral blood flow in premature infrants had important clinical significance. In order to prevent brain damage in premature, to avoid fluctuations in blood pressure, meanwhile,we should apply the ultrasound to monitor the brain lesions and the changes of MCA parameters. It is important to evaluate the hemorrhage degree and assess the prognosis in premature infants.