Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX.
Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX.
Am J Obstet Gynecol. 2020 Sep;223(3):441.e1-441.e8. doi: 10.1016/j.ajog.2020.06.018. Epub 2020 Jun 13.
Pregnant women with preeclampsia have been found to have elevated cerebral perfusion pressure and impaired cerebral autoregulation compared with normal pregnant women. Transcranial Doppler is a noninvasive technique used to estimate cerebral perfusion pressure. The effects of different antihypertensive medications on cerebral perfusion pressure in preeclampsia are unknown.
To compare the change in cerebral perfusion pressure before and after intravenous labetalol vs oral nifedipine in the setting of acute severe hypertension in pregnancy.
This is a prospective cohort study of pregnant women between 24 and 42 weeks' gestation with severe hypertension (systolic blood pressure ≥160 mm Hg and/or diastolic blood pressure ≥110 mm Hg). Women who consented to the study and received either intravenous labetalol or oral nifedipine were included. Exclusion criteria included active labor or receipt of any antihypertensive medication within 2 hours of initial cerebral perfusion pressure measurement. Peripheral blood pressure and transcranial Doppler studies for middle cerebral artery hemodynamics were performed prior to the administration of antihypertensive medications and repeated 30 minutes after medication administration.
A total of 16 women with acute severe hypertension were enrolled; 8 received intravenous labetalol and 8 received oral nifedipine. There were no significant differences between the labetalol and nifedipine groups in baseline characteristics such as maternal age, race and ethnicity, payment, hospital site, body mass index, nulliparity, gestational age, preexisting diabetes mellitus or chronic hypertension, fetal growth restriction, magnesium sulfate administration, and symptomatology (P>.05). When examined 30 minutes after the administration of either intravenous labetalol or oral nifedipine, there was a significantly greater decrease in systolic blood pressure (-9.8 mm Hg vs -39 mm Hg; P=.003), mean arterial pressure (-7.1 mm Hg vs -22.3 mm Hg; P=.02), and cerebral perfusion pressure (-2.5 mm Hg vs -27.7 mm Hg; P=.01) in the nifedipine group. There was no statistically significant decrease in diastolic blood pressure (-12.9 mm Hg vs -5.4 mm Hg; P=.15). The change in middle cerebral artery velocity by transcranial Doppler was compared between the groups and was not different (0.07 cm/s vs 0.16 cm/s; P=.64).
Oral nifedipine resulted in a significant decrease in cerebral perfusion pressure, whereas labetalol did not, after administration for acute severe hypertension among women with preeclampsia. This decrease seems to be driven by a decrease in peripheral arterial blood pressure rather than a direct change in cerebral blood flow.
与正常孕妇相比，子痫前期孕妇的脑灌注压升高，脑自动调节功能受损。经颅多普勒是一种用于估计脑灌注压的非侵入性技术。不同的降压药物对子痫前期脑灌注压的影响尚不清楚。
比较静脉注射拉贝洛尔和口服硝苯地平在急性重度妊娠高血压时对脑灌注压的影响。
这是一项前瞻性队列研究，纳入了 24 至 42 周妊娠、伴有重度高血压（收缩压≥160mmHg 和/或舒张压≥110mmHg）的孕妇。同意参加研究并接受静脉注射拉贝洛尔或口服硝苯地平的孕妇被纳入研究。排除标准包括活跃的分娩或在初始脑灌注压测量后 2 小时内接受任何降压药物。降压药物治疗前及治疗后 30 分钟进行外周血压和经颅多普勒检查，以评估大脑中动脉血流动力学。
共纳入 16 例急性重度高血压孕妇；8 例接受静脉注射拉贝洛尔，8 例接受口服硝苯地平。拉贝洛尔组和硝苯地平组在产妇年龄、种族、支付方式、医院地点、体重指数、初产妇、孕龄、是否患有糖尿病或慢性高血压、胎儿生长受限、硫酸镁使用情况和症状等方面无显著差异（P＞0.05）。静脉注射拉贝洛尔或口服硝苯地平后 30 分钟，硝苯地平组收缩压（-9.8mmHg 与-39mmHg；P=0.003）、平均动脉压（-7.1mmHg 与-22.3mmHg；P=0.02）和脑灌注压（-2.5mmHg 与-27.7mmHg；P=0.01）下降更明显。舒张压下降无统计学意义（-12.9mmHg 与-5.4mmHg；P=0.15）。经颅多普勒比较两组大脑中动脉速度的变化，差异无统计学意义（0.07cm/s 与 0.16cm/s；P=0.64）。
在子痫前期孕妇中，静脉注射拉贝洛尔和口服硝苯地平治疗急性重度高血压后，硝苯地平可显著降低脑灌注压，而拉贝洛尔则不能。这种下降似乎是由外周动脉血压下降引起的，而不是大脑血流的直接变化。
