title: Increased effective lung volume following lung volume reduction surgery in emphysema.
abstract: OBJECTIVE
  Lung volume reduction surgery (LVRS) for emphysema has a variable effect on spirometry with improvement linked to increases in lung elastic recoil. The mechanism by which recoil increases following LVRS has not been described completely. This study examines preoperative and postoperative pulmonary function to describe a mechanism for changes in airflow obstruction.
  
  
  METHODS
  Change in pulmonary function following LVRS. Setting : Public teaching hospital in Australia.
  
  
  METHODS
  Patients with severe emphysema and pulmonary function measurements made before and after LVRS.
  
  
  METHODS
  Routine pulmonary function testing performed with ventilated lung alveolar volume (VA) derived from the gas transfer measurement used as a proxy for the effective lung volume.
  
  
  RESULTS
  Pulmonary function tests from 36 consecutive patients with measurements made at the same laboratory were analyzed. The mean FEV(1) was 29.1% predicted presurgery and increased following LVRS from 0.900 L (SD, 0.427 L) to 1.283 L (SD, 0.511 L; p < 0.0001) and TLC (143% predicted) decreased from 8.19 L (SD, 1.492 L) to 7.07 L (SD, 1.52 L; p < 0.0001; n = 35). The mean VA increased by 0.674 L (SD, 0.733 L) from 4.04 to 4.72 L (p < 0.0001; n = 34). The change in FEV(1) correlated well with the change in VA (r = 0.63). The change in FEV(1) in those patients whose VAs did not increase (n = 7) was not significant.
  
  
  CONCLUSIONS
  The increase in VA reflects an increase of functional or ventilating lung volume and is associated with an improvement in spirometry following LVRS.
authors.affiliation: Respiratory Medicine Unit, The Queen Elizabeth Hospital, Woodville, Australia. sean.homan@nwahs.sa.gov.au
authors.forename: S
authors.initials: S
authors.lastname: Homan
authors.forename: S
authors.initials: S
authors.lastname: Porter
authors.forename: M
authors.initials: M
authors.lastname: Peacock
authors.forename: N
authors.initials: N
authors.lastname: Saccoia
authors.forename: A M
authors.initials: AM
authors.lastname: Southcott
authors.forename: R
authors.initials: R
authors.lastname: Ruffin
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008170:Lung Compliance / Q000502:physiology; D008176:Lung Volume Measurements; D008297:Male; D008875:Middle Aged; D011013:Pneumonectomy; D011183:Postoperative Complications / Q000209:etiology* / Q000503:physiopathology; D011656:Pulmonary Emphysema / Q000503:physiopathology / Q000601:surgery*; D011659:Pulmonary Gas Exchange / Q000502:physiology; D016896:Treatment Outcome