OC203: Carotid artery blood volume flow and elevated blood pressure in high-risk pregnancy

Abstract

Introduction: Cerebral hypoxic and ischaemic changes have been implicated in the aetiology of the characteristic seizures that signify theend-progression of pre-eclampsia. Untilrecently,neuronal dysfunction secondary to ischaemic causes or functional impairment has been difficult to study in adult humans due to the relative inaccessibility of the cerebral circulation. Doppler ultrasound now provides a means of assessing the normalcy of blood flow velocity, and has demonstrated consistency in the evaluation of severe vascular stenosis 1. Differences in systemic peripheral resistance between normotensive and preeclamptic pregnant women have also been demonstrated using calibrated carotid pulse tracings 2. Objective: To measure peak Carotid blood volume flow in a group of prospective mothers at high-risk of pregnancy hypertension and preeclampsia following uterine artery Doppler screening. Methods:Carotid artery velocimetric and blood volume flow profiles were evaluated using standardised techniques in 31 pregnant women at 24‐28 weeks gestation. Results: Blood volume flow measurement showed a 75% sensitivity for elevated blood pressure in later pregnancy, 60% sensitivity for the development of preeclampsia and 100% sensitivity for preterm preeclampsia. Conclusion: The measurement of blood volume flow in the Carotid circulation in high-risk pregnant women merits further investigation as a second-tier screening test for pregnancy hypertension and preeclampsia.