Cardiac output following fetoscopic coagulation of major placental vessels in fetal sheep.

Objectives To measure changes in cardiac output (CO) after partial cord occlusion in fetal sheep in order to investigate pathophysiological fetal adaptation mechanisms in a simulated acute placental insufficiency model under standardized conditions, with the aim of finding relevant methods for monitoring human fetuses during stress situations. Methods We used minimally invasive, percutaneous endoscopic techniques to close umbilical vessels in mid-gestational fetal sheep. Placental blood flow was reduced by preferentially closing first arterial and then the concomitant venous umbilical vessels within a short time interval. The investigations were carried out on 11 pregnant ewes at a median g…