Martin R W, Bashein G
Department of Anesthesiology, University of Washington, Seattle 98195.
Anesthesiology. 1989 Mar;70(3):470-6. doi: 10.1097/00000542-198903000-00017.
The accuracy of measuring cardiac stroke volume with a new transesophageal phased array ultrasonic probe was investigated in 10 dogs. The method involved scanning the heart to obtain serial images covering the entire left ventricular cavity at end-expiration. An off-line computer analysis of the images was used to form three-dimensional reconstructions of the left ventricular cavity at end-diastole and end-systole, from which stroke volume was determined. Comparison with stroke volume determined by thermodilution during a wide range of hemodynamic conditions gave the following results for least-squares regression on 57 determinations (with the 95% confidence limits in parentheses): slope 0.95 (0.842-1.06), ordinate intercept 2.1 (2.0-2.2) ml, standard error of the estimate 4.1 ml, and correlation coefficient of 0.92 (0.87-0.95). Histologic examination of sections of esophagus surrounding the tip of the probe in nine dogs demonstrated minimal trauma to the esophageal wall, with eight specimens described as normal and one showing mild inflammation. The authors conclude that three-dimensional reconstruction of the left ventricular cavity from multiple transesophageal images offers a safe and accurate, although presently tedious, method for determining stroke volume.
用一种新型经食管相控阵超声探头测量心搏量的准确性在10只犬身上进行了研究。该方法包括在呼气末扫描心脏以获取覆盖整个左心室腔的系列图像。对图像进行离线计算机分析，以形成舒张末期和收缩末期左心室腔的三维重建，由此确定心搏量。在广泛的血流动力学条件下，将其与通过热稀释法测定的心搏量进行比较，对57次测定进行最小二乘回归得出以下结果（括号内为95%置信限）：斜率0.95（0.842 - 1.06），纵坐标截距2.1（2.0 - 2.2）ml，估计标准误差4.1 ml，相关系数0.92（0.87 - 0.95）。对9只犬探头尖端周围食管切片的组织学检查显示食管壁仅有轻微损伤，8个标本描述为正常，1个显示轻度炎症。作者得出结论，从多个经食管图像进行左心室腔的三维重建提供了一种安全且准确的方法来测定心搏量，尽管目前该方法较为繁琐。
