Related Experiment Video
Updated: Jul 12, 2026
Investigation into Deep Breathing through Measurement of Ventilatory Parameters and Observation of Breathing Patterns
Published on: September 16, 2019
Position affects distribution of ventilation in the lungs of older people: an experimental study
Sally Krieg1, Jennifer A Alison, Bredge McCarren
1The University of Sydney, Lidcombe, NSW, 1825, Australia.
Question:
What is the effect of sitting and side-lying on the distribution of ventilation during tidal breathing in healthy older people?
Design:
Randomised, within-participant, experimental study.
Participants:
Ten healthy people more than 65 years old.
Intervention:
Tidal breathing during sitting and right side-lying.
Outcome Measures:
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.
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