Efficacy of nasal strip and furosemide in mitigating exercise-induced pulmonary
hemorrhage in Thoroughbred horses.
Kindig, Casey A., Paul McDonough, Gus Fenton, David C. Poole, and Howard H.
Erickson.
1Departments of Anatomy, Physiology and Kinesiology, Kansas State University,
Manhattan, Kansas 66506«hyphen»5602; and 2CNS, Minneapolis, Minnesota 55439
APStracts 8:0304A, 2001.
The purpose of this investigation was to study the effects of an equine nasal strip (NS),
furosemide (Fur), and a combination of both (NS + Fur) on exercise-induced pulmonary
hemorrhage (EIPH) at speeds corresponding to near-maximal effort. Five Thoroughbreds
(526 ± 25 kg) were run on a flat treadmill from 7 to 14 m/s in 1
m×s«minus»1×min«minus»1 increments every 2 wk (treatment order randomized) under
control (Con), Fur (1 mg/kg iv 4 h prior), NS, or NS + Fur conditions. During each run,
pulmonary arterial (Ppa) and esophageal (Pes) pressure were measured. Severity of EIPH
was quantified via bronchoalveolar lavage (BAL) 30 min postrun. Furosemide (Fur and
NS + Fur trials) reduced peak Ppa ~7 mmHg compared with Con (P < 0.05) whereas
NS had no effect (P > 0.05). Maximal Pes swings were not different among groups (P
> 0.05). NS significantly diminished EIPH compared with the Con trial [Con, 55.0 ±
36.2; NS, 30.8 ± 21.8 × 106 red blood cells (RBC)/ml BAL fluid; P < 0.05]. Fur
reduced EIPH to a greater extent than NS (5.2 ± 3.0 × 106 RBC/ml BAL; P < 0.05 vs.
Con and NS) with no additional benefit from NS + Fur (8.5 ± 4.2 × 106 RBC/ml BAL; P
> 0.05 vs. Fur, P < 0.05 vs. Con and NS). In conclusion, although both modalities
(NS and Fur) were successful in mitigating EIPH, neither abolished EIPH fully as
evaluated via BAL. Fur was more effective than NS in constraining the severity of EIPH.
The simultaneous use of both interventions appears to offer no further gain with respect
to reducing EIPH.
Received 20 February 2001; accepted in final form 15 May 2001
APS Manuscript Number A0163-1.
Article publication pending J Appl Physiol
ISSN 1080-4757 Copyright 2001 The American Physiological Society.
Published in APStracts on 18 June 2001