The purpose of this study was to investigate cerebral arteriolar vasoreactivity function
in preeclampsia. Preeclamptic (n = 26) and healthy pregnant (n = 22) women underwent
transcranial Doppler sonography of the middle cerebral artery at rest and after 60
seconds of hyperventilation (HV). Systolic, diastolic, and mean blood Row velocities
were recorded. The percentage change of the blood Row velocities after HV was calculated.
Mean blood flow velocity of the middle cerebral artery was higher in preeclamptic
women as compared with healthy pregnant women. No difference could be detected in
percentage change of middle cerebral artery blood Row velocities after HV between
the two groups. There is no evidence of a small-vessel vasoconstriction among preeclamptic
patients. The role of vasoconstriction of the large cerebral arteries and vasodilation
of the resistance arterioles, as well as a combination of these 2 pathomechanisms,
in determining cerebral blood flow in preeclampsia and eclampsia should be investigated
in further studies.
