title: Effect of the loading dose of magnesium sulfate (MgSO4) on the parameters of Doppler flow velocity in the uterine, umbilical and middle cerebral arteries in severe preeclampsia.
abstract: OBJECTIVE
  To evaluate Doppler velocimetry parameters (resistance index [RI], pulsatility index [PI] and systolic/diastolic [S/D] ratio) of maternal-fetal circulation before and after magnesium sulfate administration in pregnant women with severe preeclampsia.
  
  
  METHODS
  A prospective observational cohort analysis of 40 women with severe preeclampsia was performed. Doppler ultrasonography scans were performed before and 20 minutes after intravenous administration of magnesium sulfate. Maternal parameters such as heart rate, and systolic, diastolic and mean arterial pressure were recorded. Doppler flow velocity parameters (RI, PI and S/D ratio) were evaluated in the uterine, umbilical and middle cerebral arteries. The different mean values obtained before and after magnesium sulphate were analyzed using the paired t-test.
  
  
  RESULTS
  There was a statistically significant increase in mean maternal heart rate and a statistically significant decrease in systolic, diastolic and mean maternal blood pressure before and after administration of magnesium sulphate (p < 0.001). Resistance index decreased in the umbilical (p = 0.003; 95% CI: 0.008 - 0.03) and middle cerebral artery (p = 0.001; 95% CI: 0.01 - 0.05) and in both uterine arteries. Likewise, there was a significant reduction in the PI and S/D ratio in all the arteries assessed.
  
  
  CONCLUSIONS
  Maternal administration of intravenous magnesium sulfate in preeclampsia leads to an increase in maternal heart rate and a decrease in systolic, diastolic and mean arterial blood pressure. A reduction in the resistance index, pulsatility index and S/D ratio was recorded in the uterine, umbilical and cerebral arteries.
authors.affiliation: Instituto de Medicina Integral Professor Fernando Figueira-IMIP, Recife, Brazil. alexrolland@uol.com.br
authors.forename: Alex Sandro Rolland
authors.initials: AS
authors.lastname: Souza
authors.forename: Melania Maria Ramos
authors.initials: MM
authors.lastname: Amorim
authors.forename: Isabela Cristina A N C
authors.initials: IC
authors.lastname: Coutinho
authors.forename: Marcelo Marques de Souza
authors.initials: MM
authors.lastname: Lima
authors.forename: Carlos
authors.initials: C
authors.lastname: Noronha Neto
authors.forename: José Natal
authors.initials: JN
authors.lastname: Figueroa
mesh_terms: D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000008:administration & dosage*; D001783:Blood Flow Velocity / Q000187:drug effects; D005260:Female; D006801:Humans; D008278:Magnesium Sulfate / Q000008:administration & dosage*; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging / Q000187:drug effects; D011225:Pre-Eclampsia / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D011247:Pregnancy; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000000981:diagnostic imaging / Q000187:drug effects; D055988:Uterine Artery / Q000000981:diagnostic imaging / Q000187:drug effects; D055815:Young Adult
chemical_list: D000927:Anticonvulsants; D008278:Magnesium Sulfate