Skin capillary blood cell velocity in preeclampsia. The effect of plasma expansion.

Blood viscosity and peripheral vascular resistance have been reported to be increased in preeclampsia, indicating the possibility of an impaired capillary circulation. Nailfold skin capillary blood cell velocity (CBV) was measured by videophotometric capillaroscopy in 14 healthy pregnant women and 12 preeclamptic patients. No significant difference was found between basal CBV in the preeclamptic group (median 0.58 mm/s) and the healthy controls (0.52 mm/s). Following infusion of dextran 70 in preeclamptic patients CBV at rest increased to 154% of pre-infusion values (p less than 0.05). The time to peak CBV during post-occlusive reactive hyperemia was almost equal in the two groups and did not change in the preeclamptic group after dextran 70 administration. The enhanced dermal microcirculation following infusion of dextran 70 may be explained by hemodynamic and hemorheological effects, which presumably would be of greater importance if also present in the placental nutritive circulation.