Manohar M, Goetz T E
Department of Veterinary Biosciences, College of Veterinary Medicine, University of Illinois, Urbana 61801, USA.
J Appl Physiol (1985). 1996 Oct;81(4):1589-93. doi: 10.1152/jappl.1996.81.4.1589.
Exercise-induced pulmonary hemorrhage (EIPH) is a common occurrence in racehorses. The objective of this study was to compare pulmonary vascular pressures of healthy Thoroughbred horses with and without postexertion endoscopically detectable fresh blood in the trachea. The nasopharynx, larynx, and trachea (down to the carina) of horses were examined weekly with an endoscope 55-60 min postexertion, and the diagnosis of EIPH was confirmed by the presence of fresh blood in the trachea. Measurements of heart rate and right atrial, pulmonary arterial, and pulmonary arterial wedge pressures were made during quiet rest and during treadmill exercise performed at 14.5 m/s on a 5% uphill grade. This workload elicited maximal heart rate of the horses. Mean pulmonary capillary pressure was estimated to be halfway between the mean pulmonary arterial pressure and the mean pulmonary arterial wedge pressure. These data from 7 healthy sound exercise-trained horses that were positive on 12 consecutive occasions (at 1-wk intervals) for the postexercise presence of fresh blood in the trachea were compared with those in 8 healthy horses that were consistently negative for the evidence of fresh blood in the trachea on postexercise endoscopic examination over 12-16 wk. The heart rate and the right heart and/or pulmonary vascular pressures in the two groups of horses were similar at rest. Exercise was attended by a large significant (P < 0.05) increase in these pressures and heart rate in both groups. However, statistically significant differences between endoscopically EIPH-positive and endoscopically EIPH-negative horses for heart rate and right atrial and pulmonary vascular pressures were not found during exercise. Thus these data revealed that the magnitude of exercise-induced right atrial as well as pulmonary arterial, capillary, and venous hypertension in endoscopically EIPH-positive horses that are otherwise healthy is quite similar to that in endoscopically EIPH-negative horses during comparable exertion.
运动性肺出血（EIPH）在赛马中很常见。本研究的目的是比较气管内运动后内镜可检测到新鲜血液的健康纯种马与未检测到新鲜血液的健康纯种马的肺血管压力。在运动后55 - 60分钟，每周用内窥镜检查马的鼻咽、喉和气管（直至隆突），气管内出现新鲜血液则确诊为EIPH。在安静休息时以及在5%上坡坡度以14.5米/秒的速度进行跑步机运动期间，测量心率以及右心房、肺动脉和肺动脉楔压。这种运动负荷可使马达到最大心率。平均肺毛细血管压估计为平均肺动脉压和平均肺动脉楔压的中间值。将7匹健康、训练有素且连续12次（每隔1周）运动后气管内出现新鲜血液呈阳性的马的数据，与8匹在12 - 16周的运动后内镜检查中气管内始终未出现新鲜血液证据的健康马的数据进行比较。两组马在休息时的心率以及右心和/或肺血管压力相似。两组马在运动时这些压力和心率均显著大幅增加（P < 0.05）。然而，在运动期间，内镜检查EIPH阳性马和内镜检查EIPH阴性马在心率、右心房和肺血管压力方面未发现统计学上的显著差异。因此，这些数据表明，在内镜检查EIPH阳性但其他方面健康的马中，运动诱发的右心房以及肺动脉、毛细血管和静脉高压的程度与内镜检查EIPH阴性马在类似运动时的情况非常相似。
