Posture primarily affects lung tissue distribution with minor effect on blood flow and ventilation

• Published in: Respiratory physiology & neurobiology Vol. 156; no. 3; pp. 293 - 303
• Main Authors: Petersson, Johan, Rohdin, Malin, Sánchez-Crespo, Alejandro, Nyrén, Sven, Jacobsson, Hans, Larsson, Stig A, Lindahl, Sten G.E, Linnarsson, Dag, Neradilek, Blazej, Polissar, Nayak L, Glenny, Robb W, Mure, Margareta
• Format: Journal Article
• Language: English
• Published: Amsterdarm Elsevier B.V 15.06.2007; Elsevier
• Subjects: Adult; Biological and medical sciences; Data Interpretation, Statistical; Female; Fundamental and applied biological sciences. Psychology; Gravitation; Gravity; Humans; Image Interpretation, Computer-Assisted; Linear Models; Lung - anatomy & histology; Lung - diagnostic imaging; Lung - physiology; Lung Volume Measurements; Male; Medical Education; Medicin och hälsovetenskap; Posture - physiology; Prone position; Prone Position - physiology; Pulmonary Circulation - physiology; Pulmonary/Respiratory; Regional perfusion; Respiratory Mechanics - physiology; Single photon emission computed tomography; Supine position; Supine Position - physiology; Tomography, Emission-Computed, Single-Photon; Vertebrates: respiratory system; Regional perfusion; Prone position; Supine position; Single photon emission computed tomography; Gravity; Lung; Respiratory system; Photon; Blood flow; Posture; Vertebrata; Mammalia; Perfusion; Distribution; Hemodynamics; Pulmonary ventilation; Respiration; Emission tomography
• ISSN: 1569-9048; 1878-1519
• DOI: 10.1016/j.resp.2006.11.001

Abstract We used quantitative single photon emission computed tomography to estimate the proportion of the observed redistribution of blood flow and ventilation that is due to lung tissue shift with a change in posture. Seven healthy volunteers were studied awake, breathing spontaneously. Regional blood flow and ventilation were marked using radiotracers that remain fixed in the lung after administration. The radiotracers were administered in prone or supine at separate occasions, at both occasions followed by imaging in both postures. Images showed greater blood flow and ventilation to regions dependent at the time of imaging, regardless of posture at radiotracer administration. The results suggest that a shift in lung parenchyma has a major influence on the imaged distributions. We conclude that a change from the supine to the prone posture primarily causes a change in the vertical distribution of lung tissue. The effect on the vertical distribution of blood flow and ventilation within the lung parenchyma is much less.