Efficacy of furosemide in the treatment of exercise-induced pulmonary hemorrhage - OHIO STATE UNIVERSITY

Recipient Organization
OHIO STATE UNIVERSITY - VET MED
1900 COFFEY ROAD, 127L VMAB
COLUMBUS,OH 43210

Performing Department
CLINICAL SCIENCE

Non Technical Summary
Exercise-induced pulmonary hemorrage (EIPH) in Thoroughbred and Standardbred race horses costs the US racing industry an estimated $100 million annually. An additional cost of $35 million is incurred by day-of-racing administration of furosemide. However, there is no reliable evidence that furosemide has a beneficial effect on EIPH under racing conditions. Results of this study, negative or positive, will provide the first reliable information to inform and influence the highly publicized debate over the use of furosemide in racing horses.

Animal Health Component

50%

Research Effort Categories

Basic

50%

Applied

50%

Developmental

(N/A)

Classification

Knowledge Area (KA)	Subject of Investigation (SOI)	Field of Science (FOS)	Percent
315	3810	1020	100%

Knowledge Area
315 - Animal Welfare/Well-Being and Protection;

Subject Of Investigation
3810 - Horses, ponies, and mules;

Field Of Science
1020 - Physiology;

Keywords

exercise-induced pulmonary hemorrage

Goals / Objectives
To determine: 1. The effect of furosemide administration before racing on incidence of exercise-induced pulmonary hemorrhage in Thoroughbred race horses participating in competitive racing; 2. the effect of furosemide administration before racing on the severity of EIPH in Thoroughbred race horses participating in competitive racing.

Project Methods
A randomized, placebo controlled, masked trial to determine efficacy of furosemide (500 mg iv 4 hours before racing) in reducing the incidence and/or severity of EIPH (Exercise-induced Pulmonary Hemorrage)in 170 Thoroughbred horses. The number of subjects (170) is dictated by rigorous statistical power analysis based on previous studies of EIPH. Thoroughbred race horses will race in each of 2 staged races (one placebo, one furosemide) separated by at least 14 days. Presence and severity (Grade 0-4) of EIPH will be detected by tracheobronchoscopic examination. The grading system has been previously validated by us. We anticipate that furosemide will reduce EIPH incidence by 30% and severity by one grade. However, the study will have adequate statistical power to ensure that failure to detect an effect is meaningful.

Progress 07/01/06 to 03/31/07

Outputs
OUTPUTS: Exercise-induced pulmonary hemorrhage (EIPH) in Thoroughbred and Standardbred race horses costs the US racing industry an estimated $100 million annually. A cost of $35 million is incurred by day-of-raceing administration of furosemide to 90% of Thoroughbred staraters. However, there is no reliable evidence that furosemide has a beneficial effect on EIPH under racing conditions. The objective of this study was to evaluate the efficacy of furosemide for prevention of exercise-induced pulmonary hemorrhage (EIPH) in Thoroughbred racehorses under typical racing conditions. 167 Thoroughbred racehorses were used in this study. Horses were allocated to race fields of 9 to 16 horses each and raced twice, one week apart with each of the two races consisting of the same race field and distance. Each horse received furosemide (500 mg, IV) before one race and a placebo (saline solution) before the other race, with the order of treatments randomly determined. Severity of EIPH was scored on a scale from 0 to 4 after each race by means of tracheobronchoscopy. Data were analyzed by means of various methods of multivariable logistic regression. PARTICIPANTS: Dr. Hinchcliff is now Dean of the veterinary school at Sidney Australia TARGET AUDIENCES: Nothing significant to report during this reporting period. PROJECT MODIFICATIONS: Nothing significant to report during this reporting period.

Impacts
Horses were substantially more likely to develop EIPH (severity score greater than or equal to 1; odds ratio, 3.3 to 4.4) or moderate to severe EIPH (severity score greater than or equal to 2; odds ratio, 6.9 to 11.0) following administration of saline solution than following of furosemide. In addition, 81 of the 120 horses that had EIPH after administration of saline solution, had a reduction in EIPH severity score of at least 1 when treated with furosemide. Results indicated that prerace administration of furosemide decreased the incidence and severity of EIPH in Thoroughbred racing under typical conditions in South Africa.

Publications

Hinchcliff KW, Morley PS, Guthri AJ. (2009). Efficacy of furosemide for prevention of exercise-induced pulmonary hemorrhage in Thoroughbred racehorses. J Am Vet Med Assoc., Jul 1;235(1):76-82.