Vascular reactivity in preeclampsia assessed noninvasively using maternal brachial artery hyperemic response

OBJECTIVE: To estimate if women with preeclampsia had measurable differences in the brachial artery waveforms after blood flow occlusion. METHODS: In a cross-sectional study, 14 preeclamptic and 28 matched normotensive women were assessed. Hemolysis, elevated liver enzymes, low platelets syndrome patients were excluded. All patients had baseline brachial Doppler flow velocities while resting in the left lateral position and after a 60-second forearm occlusion. Doppler waveforms were analyzed from the brachial artery 30-45 seconds after the release of the blood pressure cuff. We analyzed the classical Doppler waveform parameters of systolic diastolic, mean velocity and pulsatility index, time taken to achieve peak systolic velocity, systolic acceleration time, the percentage of time in each cycle to achieve peak systolic velocity, and systolic acceleration from 3 waveforms. Comparison of the percentage change in each of these parameters between the groups was done using t tests. RESULTS: Before brachial artery occlusion, systolic acceleration time was significantly less in the preeclamptic group (77.5 +/- 14.4 milliseconds versus 93.2 +/- 11.7 milliseconds; (P <.001). After occlusion, the percentage change in the systolic acceleration and systolic acceleration time was increased in the normotensive group (P <.001). CONCLUSION: There was significantly increased impedance to blood flow downstream assessed by Doppler waveform analysis after a period of forearm ischemia (blood pressure occlusion) in the women with preeclampsia. (C) 2004 by The American College of Obstetricians and Gynecologists.