Hermida R C, Ayala D E, Mojón A, Fernández J R, Silva I, Ucieda R, Iglesias M
Bioengineering & Chronobiology Laboratories, E.T.S.I. Telecomunicación, Universidad de Vigo, Spain.
J Perinat Med. 1997;25(3):254-73.
The aims of this study were to examine whether the combined approach of 1) establishing tolerance intervals for the circadian variability of blood pressure as a function of gestational age, and 2) computing the hyperbaric index by comparison of any patient's blood pressure profile (obtained by ambulatory monitoring) with the tolerance limits, provides a new highly sensitive test for the early detection of gestational hypertension and preeclampsia. We analyzed a total of 745 blood pressure series sampled by ambulatory monitoring for about 48 hours in each of several occasions in 189 women with uncomplicated pregnancies, 71 with gestational hypertension, and 29 with preeclampsia. After synchronization of all data by expressing times of sampling in hours from bed-time, circadian tolerance limits were first computed from the normotensive subjects as a function of trimester of pregnancy. The hyperbaric index and the percentage time of excess were then computed for each individual blood pressure series. The maximum hyperbaric index was below 15 mmHg X hour for normotensive pregnant women in all trimesters of pregnancy, and mostly above that value for women who subsequently developed gestational hypertension or preeclampsia. Sensitivity of the test based on the maximum hyperbaric index was 97% for women sampled during the first trimester of gestation, and increased up to 100% in the third trimester. The positive predictive value was 100% in all trimesters. Moreover, the computation of the hyperbaric index provided, on the average, an early identification of gestational hypertension or preeclampsia 20 weeks prior to the clinical confirmation of the disease.
Ambulatory monitoring of blood pressure during gestation provides sensitive endpoints for use in early risk assessment and as a guide for establishing preventive interventions. The approach presented here represents a simple, reproducible, non-invasive, and highly sensitive test for the very early identification of gestational hypertension and preeclampsia.
本研究的目的是检验以下联合方法是否能为妊娠期高血压和先兆子痫的早期检测提供一种新的高灵敏度检测方法：1）根据孕周确定血压昼夜变异性的容许区间，2）通过将任何患者的血压曲线（通过动态监测获得）与容许限值进行比较来计算高压指数。我们分析了189例无并发症妊娠妇女、71例妊娠期高血压妇女和29例先兆子痫妇女在不同时间进行的约48小时动态血压监测所采集的总共745个血压序列。在将所有数据通过以就寝时间为起点的小时数表示采样时间进行同步后，首先根据血压正常的受试者计算出妊娠各期的昼夜容许限值。然后为每个个体血压序列计算高压指数和血压过高的百分比时间。妊娠各期血压正常的孕妇最大高压指数均低于15 mmHg×小时，而随后发生妊娠期高血压或先兆子痫的妇女大多高于该值。基于最大高压指数的检测方法在妊娠早期采样的妇女中灵敏度为97%，在妊娠晚期增至100%。所有孕期的阳性预测值均为100%。此外，高压指数的计算平均能在疾病临床确诊前20周早期识别妊娠期高血压或先兆子痫。
妊娠期动态血压监测为早期风险评估提供了敏感的指标，并可作为制定预防干预措施的指导。本文介绍的方法是一种简单、可重复、无创且高灵敏度的检测方法，用于极早期识别妊娠期高血压和先兆子痫。
