Linked Life Data

632163

Source:http://linkedlifedata.com/resource/pubmed/id/632163

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1978-5-8
pubmed:abstractText
Transpulmonary pressure, lung volume, and flow rate were recorded in two healthy subjects performing graded exercise between 1 and 10 ATA. At simulated depths greater than 4 ATA, exercise was terminated by severe choking dyspnea at levels of work, oxygen consumption, heart rate, and ventilation significantly lower than during maximum exercise at 1 ATA. Comparison of exercise ventilatory mechanics with corresponding maximum expiratory flow-volume and expiratory isovolume pressure-flow (IVPV) curves demonstrated that the reduced aerobic capacity was associated with expiratory flow limitation. We conclude that dynamic airways compression limited aerobic capacity at these depths by causing a persistent cough making it seem difficult to continue exercise. Analysis of the IVPV curves suggested that maximum expiratory flow was reduced at depth below the rate allowing adequate exercise ventilation because increased gas density raised the resistance downstream from equal pressure points. At each level of sumbaximal exercise, end-expiratory position and alveolar CO2 tension increased with ambient pressure due primarily to the density dependence of airways resistance. In these respects, healthy subjects breathing dense gas resemble patients with obstructive lung disease.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0161-7567
pubmed:author
pubmed:issnType
Print
pubmed:volume
44
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
231-7
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1978
pubmed:articleTitle
Exercise ventilatory mechanics at increased ambient pressure.
pubmed:publicationType
Journal Article