Effects of posture on chest-wall configuration and motion during tidal breathing in normal men.

[Purpose] The purpose of this study was to clarify the impact of postural changes during tidal breathing on the configuration and motion of chest-wall in order to further breathing motion evaluation. [Subjects and Methods] Chest-wall configuration and motion in the supine, right lateral, and sitting positions were measured using optoelectronic plethysmography in 15 healthy adult men. [Results] The anteroposterior diameters of the chest wall were significantly lower in the supine position for the pulmonary and abdominal rib cages, whereas the mediolateral diameters in the lateral position were lowest for the abdominal rib cage. Regarding chest-wall motion, both craniocaudal and anteroposterior motions of the anterior surface of the pulmonary and abdominal rib cages were significantly greater in the sitting position. Regarding motion of the left lateral abdominal rib cage, lateral motion was greatest in the lateral position. [Conclusion] Chest-wall configuration and motion changed according to posture in healthy men, particularly in the pulmonary and abdominal rib cages.

Measurements of chest wall volume variation during tidal breathing in the supine and lateral positions in healthy subjects.

PURPOSE: To study the feasibility and the laterality of measurements of chest wall volume variation during tidal breathing in the lateral position in healthy subjects. METHODS: Eighteen normal subjects were studied. Chest wall volume changes were measured by optoelectronic plethysmography in the supine and right and left lateral positions during quiet breathing. The accuracy of measuring lung volume was also examined using hot wire spirometry in 10 of the subjects. RESULTS: The measurement errors between lung volume changes and chest wall volume changes were not significantly different in all positions. There was no significant difference between right and left compartmental volume changes in the supine position. However, chest wall volume changes were lower on the dependent side in the lateral position than on the non-dependent side because of the decrease in abdominal rib cage and abdomen volume changes. CONCLUSION: Chest wall volume measurements during quiet breathing in the lateral position have high measuring accuracy and show laterality.