Tuberc Respir Dis.  1985 Sep;32(3):174-178. 10.4046/trd.1985.32.3.174.

The Effect of Body Positional Change on Gas Exchange in Unilateral Pleural Effusion

• KMID: 2528734
• DOI: http://doi.org/10.4046/trd.1985.32.3.174

Abstract

The effects of body position, right and left lateral decubitus, on arterial blood gases were studied in 12 patients who had unilateral pleural fluid without clinical or radiologic evidence of parenchymal lung disease. Arterial blood gases were analyzed 15 minutes after a new position. Similar studies were performed in 8 normal volunteers, the control group. Significant difference in arterial oxygen tension(Pa0₂) values between two positions were found for all patients but not for control subject. In all 12 patients, Pa0₂ values were higher when the lung with the pleural fluid was upper most. The mean Pa0₂ in this position was 70.9 ± 14.2 mmHg compared with 06. 3± 13.1 mmHg in the lateral decubitus position with the pleural fluid lower most. The mean difference in Pa0₂ between the two positions was 4.6 mmHg. Because the magnitude of the differences in Pa0₂ values between different decubitus positions for a given patient were considerable, clinical applications of the data may be therapeutically helpful.