Respiratory mechanics after 180 days space mission (EUROMIR'95).
The present study reports data on respiratory function of lung and chest wall following the 180 days long European - Russian EuroMir '95 space mission. Data reported refer to two subjects studied before the mission, on day 9 and 175 in flight and on days 1, 10, 12, 27 and 120 after return. In-flight vital capacity (VC) and expiratory reserve volume (ERV) were similar to those in supine posture, namely approximately 5% and approximately 30% less than in sitting posture. On day 1 after return, VC was reduced by approximately 30% in both postures. This reflected a decrease in ERV (approximately 0.5 L) and in IC (inspiratory capacity, approximately 1.7 L) that could be attributed to a marked weakening of the respiratory muscles. Regain of normal preflight values barely occurred 120 days after return. Post-flight pressure-volume curves of the lung, chest wall and total respiratory system are equal to preflight ones. The pressure-volume curve of the lung in supine posture is displaced to the right relative to sitting posture and shows a lower compliance. As far as the lung in-flight condition resembles that occurring in supine posture, this implies a lower compliance, a greater amount of blood in the pulmonary microvascular bed, a more homogeneous lung perfusion and therefore a greater microvascular filtration rate towards lung interstitium.
Venturoli
D
D
Istituto di Fisiologia Umana, Universita degli Studi di Milano, Italy. Daniele.Venturoli@unimi.it
Semino
P
P
Negrini
D
D
Miserocchi
G
G
D000328:Adult; D000337:Aerospace Medicine; D005105:Expiratory Reserve Volume; D006801:Humans; D007320:Inspiratory Capacity; D008297:Male; D011187:Posture / Q000502:physiology*; D015656:Respiratory Mechanics / Q000502:physiology*; D013026:Space Flight; D016683:Supine Position; D014797:Vital Capacity; D014893:Weightlessness