Khandelwal M, Rasanen J, Ludormirski A, Addonizio P, Reece E A
Department of Obstetrics, Gynecology and Reproductive Sciences, Temple University School of Medicine, Philadelphia, Pennsylvania, USA.
Obstet Gynecol. 1996 Oct;88(4 Pt 2):667-71. doi: 10.1016/0029-7844(96)00129-9.
About 4% of pregnant women have concomitant cardiac disease and a few of these do not respond to medical therapy and require surgical correction during pregnancy. We report a unique case describing fetal hemodynamics and uterine blood flow before, during, and after maternal cardiopulmonary bypass, and compare them to normal reference values in the second trimester.
A woman with severe aortic regurgitation underwent aortic valve replacement at 19 weeks' gestation. A nonpulsatile cardiac pump was used for cardiopulmonary bypass, maintaining the mean arterial pressure at 77-90 mmHg, with a peak flow rate of 3.5-4.0 L/minute/m2 and core temperature of 34-35C throughout surgery. Blood velocity waveforms were recorded by Doppler ultrasound at the level of maternal main uterine artery and fetal vessels. Pulsatility index (PI) values were calculated. Preoperatively, fetal hemodynamic characteristics were within normal limits. Preoperatively, uterine artery PI was 3.9 (normal 0.5-1.5 at 20 weeks). Intraoperatively, fetal bradycardia ensued after aortic clamping (120 to 75 beats per minute), with a rise in umbilical artery PI (1.7 to 7.1) and disappearance of diastolic flow. The middle cerebral artery PI decreased (2.0 to 0.92) and the PI increased in the descending aorta (2.22 to 3.55), inferior vena cava (2.7 to 9.3), and ductus venosus (0.6 to 1.7). During bypass, after aortic clamping, nonpulsatile uterine artery flow was noted. Postoperatively, the uterine artery PI improved, to 1.0. Two days later, hydrocephalus and hydrops were observed.
Despite high peak flow rates, normal mean arterial pressure, and normothermia, fetal outcome was dismal. Nonpulsatile cardiopulmonary bypass under normothermia may not be able to meet the demands of the fetoplacental circulation.
约4%的孕妇合并心脏病，其中少数患者药物治疗无效，孕期需要手术矫正。我们报告了一例独特的病例，描述了母体体外循环前、中、后的胎儿血流动力学和子宫血流情况，并将其与孕中期的正常参考值进行比较。
一名患有严重主动脉瓣反流的女性在妊娠19周时接受了主动脉瓣置换术。体外循环使用非搏动性心脏泵，术中平均动脉压维持在77 - 90 mmHg，峰值流速为3.5 - 4.0 L/分钟/平方米，核心体温为34 - 35°C。通过多普勒超声记录母体子宫主动脉和胎儿血管水平的血流速度波形，并计算搏动指数（PI）值。术前，胎儿血流动力学特征在正常范围内。术前子宫动脉PI为3.9（20周时正常为0.5 - 1.5）。术中，主动脉夹闭后出现胎儿心动过缓（从每分钟120次降至75次），脐动脉PI升高（从1.7升至7.1），舒张期血流消失。大脑中动脉PI降低（从2.0降至0.92），降主动脉、下腔静脉和静脉导管的PI升高（分别从2.22升至3.55、从2.7升至9.3、从0.6升至1.7）。体外循环期间，主动脉夹闭后，子宫动脉出现非搏动性血流。术后，子宫动脉PI改善至1.0。两天后，观察到脑积水和水肿。
尽管峰值流速高、平均动脉压正常且体温正常，但胎儿结局不佳。常温下的非搏动性体外循环可能无法满足胎儿 - 胎盘循环的需求。
