Impact of surgically-induced weight loss on respiratory function: a prospective analysis

Obes Surg. 2004 Nov-Dec;14(10):1389-92. doi: 10.1381/0960892042583996.


Background: Morbid obesity (MO) causes several degrees of respiratory impairment that may resolve after weight reduction. The aims of the present study were to investigate the frequency of respiratory impairment in a selected cohort of morbidly obese patients with BMI 40-50 kg/m(2) with no respiratory symptoms and to evaluate the impact of surgically-induced weight loss on respiratory function.

Methods: Prospective analysis of respiratory impairment was conducted before surgery and 1 year after surgery in a cohort of patients with MO who underwent vertical banded gastroplasty (VBG). 30 consecutive patients with MO who underwent VBG (14 open and 16 laparoscopic) in a 1-year period were studied. Respiratory function tests, arterial blood gases and hemoglobin were obtained in all patients before and 1 year after VBG.

Results: Results were analyzed using the Wilcoxon signed-rank test and Spearman for variables without normal distribution. Mean age was 35+/-8 years; there were 3 males and 27 females. BMI was 44+/-4 kg/m(2) before surgery and 32+/-4 kg/m(2) at 1-year follow-up. By respiratory function tests, the diagnosis of obstructive disease was made before surgery in 4 patients and a restrictive disorder was identified in 4 additional patients. Evidence of pulmonary disease was absent in all patients 1 year after surgery. Forced vital capacity, inspiratory and expiratory forces, tidal volume, SaO(2), and PaCO(2) significantly improved after weight reduction.

Conclusion: Surgically-induced weight loss significantly improves pulmonary function.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Body Mass Index
  • Female
  • Follow-Up Studies
  • Gastroplasty / methods*
  • Humans
  • Hypoventilation / etiology
  • Hypoventilation / physiopathology*
  • Laparoscopy / methods
  • Male
  • Middle Aged
  • Obesity, Morbid / diagnosis
  • Obesity, Morbid / surgery*
  • Probability
  • Prospective Studies
  • Pulmonary Gas Exchange
  • Respiratory Function Tests
  • Risk Assessment
  • Severity of Illness Index
  • Sleep Apnea, Obstructive / etiology
  • Sleep Apnea, Obstructive / physiopathology*
  • Time Factors
  • Treatment Outcome
  • Vital Capacity
  • Weight Loss*