Doppler Velocimetry Changes After Administration of Magnesium Sulfate in Severe Preeclampsia : Mansoura Experience

Aim: Intravenous administration of MgSO4 to pregnant women with severe preeclampsia to prevent seizures in pregnant females with severe preeclampsia. Materials and Methods: This study was conducted at Mansoura University Hospital from November 2018 to December 2019. Doppler indices of uterine artery, umbilical artery (UA), fetal middle cerebral artery (MCA) were measured before, 20 minutes after IV loading dose of 6gm of MgSO4, and after administration of maintenance dose of 1gm/hr. of MgSO4 for 24 hours. Results: There was a significant difference between maternal heart rate, systolic, diastolic and mean blood pressure before and 20 minutes after administration of loading dose of MgSO4 ( p value < 0.001 ) and a significant difference also before and after completing administration of maintenance dose of MgSO4 ( p value < 0.001 ). There was a significant difference between RI, PI, and S/D ratio of uterine artery, UA, and MCA before and 20 minutes after administration of loading dose of MgSO4 ( p value < 0.001 ) and a significant difference also between before and after 24 hours ( p value < 0.001 ). The cerebroumbilical ratio had significant change as regards RI and S/D. However, there was no significant change as regards PI. The decrease in Doppler parameters of MCA was more than the decrease in those of UA. Conclusion: IV administration of the loading dose then the maintenance dose of MgSO4 resulted in decrease in Doppler indices of uterine artery, UA, fetal MCA and increased cerebroumbilical ratio indicating improved fetal cerebral perfusion and affinity of cerebral vessels to MgSO4.