Abstract
The morbidly obese are known to have impaired respiratory function. A prospective study of the changes in lung volumes, carbon monoxide transfer, and arterial blood gas tensions was undertaken in 29 morbidly obese patients before and after surgery to induce weight loss. Before surgery the predominant abnormality in respiratory function was a reduction in lung volumes. These increased towards normal predicted values after weight loss, with significant increases in functional residual capacity, residual volume, total lung capacity, and expiratory reserve volume. The increases ranged from 14% for total lung capacity to 54% for expiratory reserve volume. After weight loss had been induced the smokers showed mild hyperinflation and air trapping. Resting arterial blood gas tensions improved, with a rise in arterial oxygen tension from 10.63 to 13.02 kPa and a fall in arterial carbon dioxide tension from 5.20 to 4.64 kPa. There was no correlation between weight loss and the changes in blood gas tensions or lung volumes. Loss of weight in the morbidly obese is thus associated with improved lung function. The effects of smoking on lung function could be detected after weight loss, but were masked before treatment by the opposing effects of obesity on residual volume and functional residual capacity.
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- BICKELMANN A. G., BURWELL C. S., ROBIN E. D., WHALEY R. D. Extreme obesity associated with alveolar hypoventilation; a Pickwickian syndrome. Am J Med. 1956 Nov;21(5):811–818. doi: 10.1016/0002-9343(56)90094-8. [DOI] [PubMed] [Google Scholar]
- Barrera F., Hillyer P., Ascanio G., Bechtel J. The distribution of ventilation, diffusion, and blood flow in obese patients with normal and abnormal blood gases. Am Rev Respir Dis. 1973 Oct;108(4):819–830. doi: 10.1164/arrd.1973.108.4.819. [DOI] [PubMed] [Google Scholar]
- Flejou J. F., Owen E. R., Smith A. C., Price A. B. Effect of vertical banded gastroplasty on the natural history of gastritis in patients with morbid obesity: a follow-up study. Br J Surg. 1988 Jul;75(7):705–707. doi: 10.1002/bjs.1800750728. [DOI] [PubMed] [Google Scholar]
- Holley H. S., Milic-Emili J., Becklake M. R., Bates D. V. Regional distribution of pulmonary ventilation and perfusion in obesity. J Clin Invest. 1967 Apr;46(4):475–481. doi: 10.1172/JCI105549. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Mason E. E. Vertical banded gastroplasty for obesity. Arch Surg. 1982 May;117(5):701–706. doi: 10.1001/archsurg.1982.01380290147026. [DOI] [PubMed] [Google Scholar]
- NAIMARK A., CHERNIACK R. M. Compliance of the respiratory system and its components in health and obesity. J Appl Physiol. 1960 May;15:377–382. doi: 10.1152/jappl.1960.15.3.377. [DOI] [PubMed] [Google Scholar]
- Rochester D. F., Enson Y. Current concepts in the pathogenesis of the obesity-hypoventilation syndrome. Mechanical and circulatory factors. Am J Med. 1974 Sep;57(3):402–420. doi: 10.1016/0002-9343(74)90135-1. [DOI] [PubMed] [Google Scholar]
- Santesson J., Nordenström J. Pulmonary function in extreme obesity. Influence of weight loss following intestinal shunt operation. Acta Chir Scand Suppl. 1978;482:36–40. [PubMed] [Google Scholar]
- Sugerman H. J., Fairman R. P., Baron P. L., Kwentus J. A. Gastric surgery for respiratory insufficiency of obesity. Chest. 1986 Jul;90(1):81–86. doi: 10.1378/chest.90.1.81. [DOI] [PubMed] [Google Scholar]
- Vaughan R. W., Cork R. C., Hollander D. The effect of massive weight loss on arterial oxygenation and pulmonary function tests. Anesthesiology. 1981 Apr;54(4):325–328. doi: 10.1097/00000542-198104000-00013. [DOI] [PubMed] [Google Scholar]
- Walsh R. E., Michaelson E. D., Harkleroad L. E., Zighelboim A., Sackner M. A. Upper airway obstruction in obese patients with sleep disturbance and somnolence. Ann Intern Med. 1972 Feb;76(2):185–192. doi: 10.7326/0003-4819-76-2-185. [DOI] [PubMed] [Google Scholar]