Payne R A, Isnardi D, Andrews P J D, Maxwell S R J, Webb D J
Clinical Pharmacology Unit, Centre for Cardiovascular Science, he University of Edinburgh, Edinburgh, UK.
Br J Anaesth. 2007 Nov;99(5):653-61. doi: 10.1093/bja/aem258. Epub 2007 Sep 13.
Wideband external pulse (WEP) monitoring, using a broad bandwidth piezoelectric sensor located over the brachial artery under the distal edge of a sphygmomanometer cuff, can be used for evaluating the contour of the arterial pressure pulse wave. The pulse contour contains valuable information relating to cardiovascular function which may be of clinical use in addition to blood pressure measurements. The aim of this study was to compare the shape of the WEP signal during inflation of the cuff to suprasystolic pressure, with intra-arterial pressure waves, after the administration of vasoactive drugs.
Radial intra-arterial and suprasystolic WEP waveforms were recorded in 11 healthy men (mean 23 yr) before and at the end of infusion of glyceryl trinitrate, angiotensin II, norepinephrine, and salbutamol. Waveform similarity was assessed by comparing the timing and pressure of incident and reflected waves and by root mean square error (RMSE).
The WEP signal was found to closely resemble the first derivative of intra-arterial pressure. The WEP signal could be used to derive an arterial pressure wave with minimal bias in the timing of incident [- 8 (18) ms, mean (SD)] and reflected [- 1 (24) ms] waves. Augmentation index was underestimated by WEP [- 7 (18)%]. WEP also provided a measure of compliance which correlated with pulse wave velocity (r = - 0.44). RMSE values after the administration of each of the four drugs mentioned earlier were 12.4 (3.8), 17.7 (5.0), 22.1 (11.7), and 28.9 (22.4) mm Hg, respectively. Changes in derived WEP signals were similar to those measured by arterial line with all drugs.
The suprasystolic WEP signals can be used to derive arterial pressure waves which, although not identical, track changes in the intra-arterial pulse wave induced by vasoactive drugs.
宽带外部脉搏（WEP）监测，通过将一个宽带宽压电传感器置于血压计袖带远端边缘下方的肱动脉上方，可用于评估动脉压力脉搏波的轮廓。脉搏轮廓包含与心血管功能相关的有价值信息，除血压测量外，这些信息可能具有临床用途。本研究的目的是比较在袖带充气至收缩压以上时WEP信号的形状与血管活性药物给药后动脉内压力波的形状。
在11名健康男性（平均23岁）中，于静脉输注硝酸甘油、血管紧张素II、去甲肾上腺素和沙丁胺醇之前及输注结束时记录桡动脉内和收缩压以上的WEP波形。通过比较入射波和反射波的时间及压力以及均方根误差（RMSE）来评估波形相似性。
发现WEP信号与动脉内压力的一阶导数非常相似。WEP信号可用于得出动脉压力波，入射波[-8（18）毫秒，均值（标准差）]和反射波[-1（24）毫秒]的时间偏差最小。增强指数被WEP低估了[-7（18）%]。WEP还提供了一种与脉搏波速度相关的顺应性测量方法（r = -0.44）。上述四种药物给药后，RMSE值分别为12.4（3.8）、17.7（5.0）、22.1（11.7）和28.9（22.4）毫米汞柱。所有药物作用下，导出的WEP信号变化与动脉内测量结果相似。
收缩压以上的WEP信号可用于得出动脉压力波，尽管二者并不完全相同，但可追踪血管活性药物引起的动脉内脉搏波变化。
