Exercise-Induced Pulmonary Hemorrhage by K.W. Hinchcliff; P2663.1205

Exercise-induced pulmonary hemorrhage (EIPH) is ubiquitous among Thoroughbred racehorses throughout the world, and there is no apparent important geographic variation in incidence of the condition. Although EIPH is very common, the exact incidence of the condition varies depending on the method of diagnosis and the frequency of examination. Examination of bronchoalveolar lavage fluid (BAL) or transtracheal aspirate from horses in training or racing reveals evidence (presence of red blood cells or hemosiderin-laden macrophages) of pulmonary hemorrhage in almost all such horses. However, bronchoscopic examination of horses after racing is currently the preferred means of detecting and quantifying EIPH in horses. Examination of Thoroughbred horses within 2 h of racing shows an incidence of EIPH of between 42% and 90%, depending on whether the horses are selected for examination because of the presence of epistaxis or other clinical abnormalities or are selected at random. This review will consider evidence of the cost of EIPH to racing industries, the methods of assessment of the severity of EIPH, and the association of EIPH and racing performance. Results of recent studies are discussed.