Preeclampsia postpartum: Impairment of cerebral autoregulation and reversible cerebral hyperperfusion.

Objectives: Preeclampsia is a pregnancy-related hypertensive disorder with endothelial dysfunction. Impaired cerebral autoregulation may lead to symptomatic cerebral hyperperfusion, which sometimes manifests not until after delivery. This study investigated, whether cerebral autoregulation was altered after delivery in healthy and preeclamptic women, and whether this associated with cerebral hyperperfusion.

Study Design: In a prospective study, 35 preeclamptic and 35 healthy women were examined with transcranial Doppler within 10 days postpartum and 6 months later. Continuous arterial blood pressure and cerebral blood flow velocities (CBFV) in the middle (MCA) and posterior cerebral arteries (PCA) were recorded at rest.

Main Outcome Measures: Dynamic cerebral autoregulation was assessed upon regular breathing at 0.1 Hz via transfer function phase and gain between arterial blood pressure and CBFV oscillations.

Results: In preeclamptic women, phase was reduced after delivery in both, MCA and PCA. During the postpartum period, CBFV of the MCA, but not PCA, correlated with higher arterial blood pressure and poorer dynamic cerebral autoregulation. In healthy women with only moderately altered cerebral autoregulation, CBFV remained in the normal range. At both measurements, arterial blood pressure was higher in preeclamptic compared to healthy women.

Conclusions: Women with preeclampsia had poorer cerebral autoregulation and an increased risk of transient cerebral hyperperfusion after delivery.