Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1998-6-4
pubmed:abstractText
During short-term maximal exercise, horses have impaired pulmonary gas exchange, manifested by diffusion limitation and arterial hypoxemia, without marked ventilation-perfusion (VA/Q) inequality. Whether gas exchange deteriorates progressively during prolonged submaximal exercise has not been investigated. Six thoroughbred horses performed treadmill exercise at approximately 60% of maximal oxygen uptake until exhaustion (28-39 min). Multiple inert gas, blood-gas, hemodynamic, metabolic rate, and ventilatory data were obtained at rest and 5-min intervals during exercise. Oxygen uptake, cardiac output, and alveolar-arterial PO2 gradient were unchanged after the first 5 min of exercise. Alveolar ventilation increased progressively during exercise, from increased tidal volume and respiratory frequency, resulting in an increase in arterial PO2 and decrease in arterial PCO2. At rest there was minimal VA/Q inequality, log SD of the perfusion distribution (log SDQ) = 0.20. This doubled by 5 min of exercise (log SDQ = 0.40) but did not increase further. There was no evidence of alveolar-end-capillary diffusion limitation during exercise. However, there was evidence for gas-phase diffusion limitation at all time points, and enflurane was preferentially overretained. Horses maintain excellent pulmonary gas exchange during exhaustive, submaximal exercise. Although VA/Q inequality is greater than at rest, it is less than observed in most mammals and the effect on gas exchange is minimal.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
8750-7587
pubmed:author
pubmed:issnType
Print
pubmed:volume
84
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1723-30
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Effect of prolonged heavy exercise on pulmonary gas exchange in horses.
pubmed:affiliation
Department of Medicine, University of California San Diego, La Jolla 92093-0623, USA. shopkins@ucsd.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.