Effect of Carbon Dioxide on Diaphragmatic Function in Human Beings
- 5 April 1984
- journal article
- research article
- Published by Massachusetts Medical Society in New England Journal of Medicine
- Vol. 310 (14) , 874-879
- https://doi.org/10.1056/nejm198404053101402
Abstract
We studied the effects of acute changes in the partial pressure of arterial carbon dioxide on diaphragmatic contractility and performance in four normal men. To study contractility we measured the ability of the diaphragm to generate pressure at a given level of excitation by determining the relation between the electrical activity of the diaphragm and transdiaphragmatic pressure during a voluntary quasi-isometric inspiratory effort carried out at different levels of end-tidal carbon dioxide. Our results show that contractility was reduced with hypercapnia (when end-tidal carbon dioxide was 7.5 per cent or higher), although hypocapnia (end-tidal carbon dioxide, 3 per cent) had no effect on diaphragmatic contractility. We also studied the development of diaphragmatic fatigue before and during carbon dioxide breathing. Subjects were studied at the same diaphragmatic tension–time index, a value analogous to the more familiar myocardial tension–time index, while the same inspiratory flow was maintained. Electromyographic signs of fatigue appeared at a lower tension–time index during hypercapnia than during normocapnia, indicating that endurance is diminished during hypercapnia. These findings show that acute respiratory acidosis equivalent to an arterial carbon dioxide tension of about 54 mm Hg decreases the contractility and endurance time of the diaphragm in human beings. (N Engl J Med 1984;310:874–9.)This publication has 27 references indexed in Scilit:
- Effects of acidosis and ischemia on contractility and intracellular pH of rat heart.Circulation Research, 1977
- Factors in the Interpretation of Mouth Occlusion Pressure during Measurements of ChemosensitivityChest, 1976
- Influence of lung volume and electrode position on electromyography of the diaphragmJournal of Applied Physiology, 1976
- Contractility in Isolated Mammalian Heart Muscle after Acid-Base ChangesCirculation Research, 1970
- Extracellular vs. intracellular pH as a determinant of myocardial contractilityLife Sciences, 1969
- Effects of Changes in Coronary Blood pH on the HeartCirculation Research, 1965
- Improved technique for estimating pleural pressure from esophageal balloonsJournal of Applied Physiology, 1964
- Abdominal and thoracic pressures at different lung volumesJournal of Applied Physiology, 1960
- Bicarbonate ion and striated muscleThe Journal of Physiology, 1949
- On the Tonicity of the Heart and Blood Vessels1The Journal of Physiology, 1880