Young L E, Blissitt K J, Bartram D H, Clutton R E, Molony V, Jones R S
Department of Veterinary Clinical Studies, Royal (Dick) School of Veterinary Studies, Midlothian.
Br J Anaesth. 1996 Dec;77(6):773-80. doi: 10.1093/bja/77.6.773.
In order to determine if transoesophageal Doppler echocardiography could be used to estimate cardiac output in anaesthetized horses, we have compared the technique with estimations of cardiac output by thermodilution in eight healthy adult thoroughbreds. Measurements of aortic blood flow velocity were made by high pulse repetition frequency (HPRF) and continuous wave (CW) Doppler echocardiography from a 3.5-MHz transoesophageal probe. Cardiac output was increased during the study by administration of dobutamine, providing a range of cardiac output measurements by thermodilution from 15.0 to 64.4 liter min-1. Estimations derived from CW Doppler overestimated cardiac output compared with thermodilution (bias = 4.0 litre min-1). Estimations from HPRF Doppler echocardiography more closely reflected measurements obtained by thermodilution (bias = 0.7 litre min-1). Limits of agreement between the techniques were similar for both modes of insonation (HPRF = -7.7 to 9.1 litre min-1, CW = -4.9 to 12.8 litre min-1). There were significant differences in bias between both Doppler techniques and thermodilution for individual horses. As a result, for any individual horse, limits of agreement between the techniques were closer (HPRF = +/- 6.4 litre min-1, CW = +/- 7.6 litre min-1). We conclude that transoesophageal echocardiography provided an alternative, effective and non-invasive method for measurement of cardiac output in anaesthetized horses.
为了确定经食管多普勒超声心动图是否可用于估计麻醉马匹的心输出量，我们在8匹健康成年纯种马中，将该技术与热稀释法估计的心输出量进行了比较。使用3.5MHz经食管探头，通过高脉冲重复频率（HPRF）和连续波（CW）多普勒超声心动图测量主动脉血流速度。在研究过程中，通过给予多巴酚丁胺增加心输出量，热稀释法测得的心输出量范围为15.0至64.4升/分钟。与热稀释法相比，CW多普勒测得的估计值高估了心输出量（偏差=4.0升/分钟）。HPRF多普勒超声心动图的估计值更接近热稀释法获得的测量值（偏差=0.7升/分钟）。两种探测模式下，两种技术之间的一致性界限相似（HPRF=-7.7至9.1升/分钟，CW=-4.9至12.8升/分钟）。对于每匹马，两种多普勒技术与热稀释法之间的偏差存在显著差异。因此，对于任何一匹马，两种技术之间的一致性界限更窄（HPRF=±6.4升/分钟，CW=±7.6升/分钟）。我们得出结论，经食管超声心动图为测量麻醉马匹的心输出量提供了一种替代、有效且无创的方法。
