Fig. 1

Ex vivo placental perfusion model. After cannulation of a fetal artery and vein pair, the cotyledon is placed in the perfusion chamber with the maternal side facing up. Access to the intervillous space is provided by penetration of the decidual plate with three blunt cannulas. The maternal perfusate leaves the intervillous space through venous openings and is returned to the maternal circulation through a tube connected to a peristaltic pump. The perfusion chamber is surrounded by a water jacket connected to a 37 °C water circuit. The maternal and fetal reservoirs are placed on hot magnetic stirrers to ensure a temperature of the perfusate of 37 °C. The fetal perfusate is equilibrated with 95 % N₂ and 5 % CO₂ which is added to the reservoir. An oxygenator inserted into the maternal circulation equilibrates the maternal perfusate with atmospheric air