Künzel W
Fortschr Med. 1976 Jun 3;94(16):949-53.
In late pregnancy about 10% of the patients suffer from dizziness and a shock symptomatic if placed in a supine position. These symptoms are reversible if the patient turns to the lateral position. In the present paper experiments in human and sheep are reviewed. The cause for this disease is the occlusion of the inferior vena cava by the gravid uterus. The venous backflow to the maternal heart is reduced and the cardiac output decreased by about 1 1/min. The total peripheral resistance (TPR) is increased (Lees et al. 1967b). The increase in TPR is due to the compression of the vena cava by the uterus and not related to an increased arterial tone during the first time course. The fall in mean arterial blood pressure is of varying degree and paralleled by an increase of the blood pressure in the vena cava below the compression and the uterine vein. The fall of the mean arterial blood pressure war related to the decrease of the perfusion pressure. The fall in arterial blood pressure and most important the rise of the uterine vein blood pressure led to a decrease of the perfusion pressure across the uterus. The uterine blood flow fell proportional to the drop of perfusion pressure. The uterine vasculare resistance remained unchanged. The fall of uterine blood flow was associated with a fall of fetal heart rate.
在妊娠晚期，约10%的患者仰卧时会出现头晕和休克症状。如果患者转为侧卧位，这些症状是可逆的。本文综述了在人和羊身上进行的实验。这种疾病的病因是妊娠子宫压迫下腔静脉。母体心脏的静脉回流减少，心输出量降低约1升/分钟。总外周阻力（TPR）增加（利斯等人，1967b）。TPR的增加是由于子宫对腔静脉的压迫，而不是在最初阶段动脉张力增加所致。平均动脉血压下降程度不同，同时受压下方的腔静脉和子宫静脉血压升高。平均动脉血压的下降与灌注压的降低有关。动脉血压的下降，最重要的是子宫静脉血压的升高，导致子宫灌注压降低。子宫血流量与灌注压的下降成比例下降。子宫血管阻力保持不变。子宫血流量的下降与胎儿心率的下降有关。
