Common sources of poor performance
• Lameness
• Upper airway
• Lower airway
• Cardiac
• Myopathy
• Or any combination of the above
Incidences of causes of poor performance
• Morris EA et al (EVJ 1991;23:169-174)
o
275 racehorses
o
84% had more than one problem
o
40% dx with airway obstruction
• Martin BB et al (JAVMA 2000:216(4):554-558)
o Definitive diagnosis only in 73.5%
o
43% dynamic airway obstruction
o
22% clinically important arrhythmias
o
15% had concurrent airway obstruction
o
7% rhabdomyolyis
o
10% lameness
o
36% subclinical myopathy
• Wilsher S et al (EVJ 2006:38(2) 113-118)
o
Musculoskeletal problems
• 55% of 2 year olds
• 45% of 3 year olds
• Sore shins the most common problem (29%, 12%)
o
Respiratory problems
• 16% of 2 year olds
• 13% of 3 year olds
• IAD the most common problem (13%, 8%)
• Inflammatory airway disease
o
22-50% incidence
o
Neutrophilic inflammation in bronchi, bronchioles, and trachea
o
Tracheal mucus accumulation
o
BAL
• total nucleated cells
• Total and % neutrophils
• Total and % lymphocytes
• Mast cells
• Eosinophils
o
TTW = neutrophilic inflammation
o
Associated with EIPH, environmental exposure to respiratory irritants, specific bacteria
Diagnostics for poor performance
• Field diagnostics
• High speed treadmill exam
Upper airway
• Resting endoscopy
• Nasal occlusion
o
Achieves pharyngeal and tracheal pressures consistent with maximal exercise (Holcombe SJ et al AJVR 1996 Sep;57(9):1258-60)
• Treadmill endoscopy
• Field exercising endoscopy
• Evaluation of poor performance
Lower airway
• Disorders include:
o
Inflammatory Airway Disease (IAD)
o
Exercise Induced Pulmonary Hemorrhage (EIPH)
• Diagnostics
o
Bronchoalveolar lavage
• 100-250 ml of sterile fluids drawn up into 60cc syringes
