title: Position affects distribution of ventilation in the lungs of older people: an experimental study.
abstract: OBJECTIVE
  What is the effect of sitting and side-lying on the distribution of ventilation during tidal breathing in healthy older people?
  
  
  METHODS
  Randomised, within-participant, experimental study.
  
  
  METHODS
  Ten healthy people more than 65 years old.
  
  
  METHODS
  Tidal breathing during sitting and right side-lying.
  
  
  METHODS
  Distribution of ventilation as a percentage of total counts using Technetium-99m Technegas lung ventilation imaging.
  
  
  RESULTS
  In sitting, the ratio of the distribution of ventilation to apical: middle: basal regions was 1: 3.5: 3.3 in the right lung, and 1: 2.9: 2.3 in the left lung. In right side-lying, 32% (95% CI 22 to 43) more ventilation was distributed to the right lung than to the left lung. The ratio of the distribution of ventilation to apical: middle: basal regions was 1: 2.8: 2.2 in the right lung, and 1: 2.4: 1.9 in the left lung.
  
  
  CONCLUSIONS
  In both sitting and right side-lying, ventilation was distributed more to the middle than to the basal region, which may be related to age-associated changes in the respiratory system.
authors.affiliation: The University of Sydney, Lidcombe, NSW, 1825, Australia.
authors.forename: Sally
authors.initials: S
authors.lastname: Krieg
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Alison
authors.forename: Bredge
authors.initials: B
authors.lastname: McCarren
authors.forename: Simon
authors.initials: S
authors.lastname: Cowell
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D006801:Humans; D008168:Lung / Q000000981:diagnostic imaging / Q000502:physiology; D011187:Posture / Q000502:physiology*; D012123:Pulmonary Ventilation / Q000502:physiology*; D011877:Radionuclide Imaging; D015656:Respiratory Mechanics / Q000502:physiology; D013990:Tidal Volume / Q000502:physiology