Journal article
Impaired Reflex Vasoconstriction in Chronically Hypoxemic Patients
The Journal of clinical investigation, Vol.51(2), pp.331-337
02/1972
DOI: 10.1172/JCI106818
PMCID: PMC302131
PMID: 5009117
Abstract
Acute hypoxia impairs vasoconstrictor responses in normal men. The present study was done to determine whether reflex vasoconstriction is impaired in chronically hypoxemic patients and whether correction of hypoxemia in these patients improves their cardiovascular reflexes. In eight chronically hypoxemic patients, arterial P\nO2\nwas increased from an average of 45 mm Hg while breathing room air to 161 mm Hg while breathing 40-100% oxygen, with minimal changes in arterial P\nCO2\nor pH. Correction of hypoxemia did not cause changes in resting arterial pressure or in forearm vascular resistance, but it caused a small increase in resting heart rate. Reflex responses to lower body negative pressure, which causes pooling of blood in the lower part of the body, were observed. When the patients were hypoxemic, lower body negative pressure caused a fall in arterial pressure, slight constriction of forearm vessels, and a small increase in heart rate. When hypoxemia was corrected, the same intervention caused marked vasoconstriction and a greater increase in heart rate, and there was no decrease in arterial pressure. The results indicate that reflex vasoconstrictor responses are depressed in chronic hypoxemia, indicating that adaptive mechanisms which occur in chronic hypoxemia do not include preservation of sympathetic reflexes.
Details
- Title: Subtitle
- Impaired Reflex Vasoconstriction in Chronically Hypoxemic Patients
- Creators
- Donald D Heistad - Cardiovascular Division, Department of Internal Medicine, Veterans Administration Hospital and University of Iowa College of Medicine, Iowa City, Iowa 52240Francois M Abboud - Cardiovascular Division, Department of Internal Medicine, Veterans Administration Hospital and University of Iowa College of Medicine, Iowa City, Iowa 52240Allyn L Mark - Cardiovascular Division, Department of Internal Medicine, Veterans Administration Hospital and University of Iowa College of Medicine, Iowa City, Iowa 52240Phillip G Schmid - Cardiovascular Division, Department of Internal Medicine, Veterans Administration Hospital and University of Iowa College of Medicine, Iowa City, Iowa 52240
- Resource Type
- Journal article
- Publication Details
- The Journal of clinical investigation, Vol.51(2), pp.331-337
- Publisher
- American Society for Clinical Investigation
- DOI
- 10.1172/JCI106818
- PMID
- 5009117
- PMCID
- PMC302131
- ISSN
- 0021-9738
- eISSN
- 1558-8238
- Language
- English
- Date published
- 02/1972
- Academic Unit
- Molecular Physiology and Biophysics; Cardiovascular Medicine; Fraternal Order of Eagles Diabetes Research Center; Neuroscience and Pharmacology; Internal Medicine
- Record Identifier
- 9984025371602771
Metrics
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