Vyas S, Nicolaides K H, Bower S, Campbell S
Department of Obstetrics and Gynaecology, King's College Hospital, London, England.
Br J Obstet Gynaecol. 1990 Sep;97(9):797-803. doi: 10.1111/j.1471-0528.1990.tb02573.x.
In 81 small-for-gestational age fetuses (SGA) colour flow imaging was used to identify the fetal middle cerebral artery for subsequent pulsed Doppler studies. Impedence to flow (pulsatility index; PI) was significantly lower, and mean blood velocity was significantly higher, than the respective reference ranges with gestation. Fetal blood sampling by cordocentesis was performed in all SGA fetuses and a significant quadratic relation was found between fetal hypoxaemia and the degree of reduction in the PI of FVWs from the fetal middle cerebral artery. Thus, maximum reduction in PI is reached when the fetal PO2 is 2-4 SD below the normal mean for gestation. When the oxygen deficit is greater there is a tendency for the PI to rise, and this presumably reflects the development of brain oedema.
在81例小于胎龄儿（SGA）中，使用彩色血流成像识别胎儿大脑中动脉，以便随后进行脉冲多普勒研究。与相应的孕周参考范围相比，血流阻抗（搏动指数；PI）显著降低，平均血流速度显著升高。对所有SGA胎儿进行了经皮脐血穿刺采集胎儿血样，发现胎儿低氧血症与胎儿大脑中动脉血流速度波形的PI降低程度之间存在显著的二次关系。因此，当胎儿血氧分压低于孕周正常均值2 - 4个标准差时，PI达到最大降低。当缺氧程度更大时，PI有上升趋势，这可能反映了脑水肿的发展。
