TY - JOUR
T1 - Effects of Elastic Loading and Exercise on Pulmonary Gas Exchange in Dogs
AU - Chonan, Tatsuya
AU - Hida, Wataru
AU - Kikuchi, Yoshihiro
AU - Shindoh, Chiyohiko
AU - Taguchi, Osamu
AU - Miki, Hiroshi
AU - Takishima, Tamotsu
PY - 1991
Y1 - 1991
N2 - We assessed the effects of negative intrathoracic pressure induced by inspiratory elastic loading on pulmonary, gas exchange with and without electrically induced hindlimb exercise in 8 normal, anesthetized dogs. Two elastic loads (EL) were used; one of 81 and one of 140cmH2O/liter. These are equivalent to doubling and tripling the normal elastance of the dog's respiratory system, respectively. Elastic loading decreased ventilation and caused hypoxemia and hypercapnia, but it did not affect systemic arterial pressure or heart rate. During exercise, increase in ventilation was limited, whereas increase in cardiac output was not affected by elastic loading. Alveolar-arterial O2 tension difference (A-aDO2) was not changed significantly by exercise alone. However, elastic loading accompanied by exercise increased A-aDO2. Although comparable end-inspiratory pleural pressure was achieved with large EL (-29±2cmH2O, mean±SE) and small EL with exercise (-30± 2cmH2O), the latter increased A-aDO2 whereas the former did not. Large negative intrapleural pressure combined with increased cardiac output may have caused transient interstitial edema.
AB - We assessed the effects of negative intrathoracic pressure induced by inspiratory elastic loading on pulmonary, gas exchange with and without electrically induced hindlimb exercise in 8 normal, anesthetized dogs. Two elastic loads (EL) were used; one of 81 and one of 140cmH2O/liter. These are equivalent to doubling and tripling the normal elastance of the dog's respiratory system, respectively. Elastic loading decreased ventilation and caused hypoxemia and hypercapnia, but it did not affect systemic arterial pressure or heart rate. During exercise, increase in ventilation was limited, whereas increase in cardiac output was not affected by elastic loading. Alveolar-arterial O2 tension difference (A-aDO2) was not changed significantly by exercise alone. However, elastic loading accompanied by exercise increased A-aDO2. Although comparable end-inspiratory pleural pressure was achieved with large EL (-29±2cmH2O, mean±SE) and small EL with exercise (-30± 2cmH2O), the latter increased A-aDO2 whereas the former did not. Large negative intrapleural pressure combined with increased cardiac output may have caused transient interstitial edema.
KW - alveolar-arterial oxygen tension difference
KW - exercise
KW - loaded breathing
KW - pulmonary gas exchange
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U2 - 10.1620/tjem.164.157
DO - 10.1620/tjem.164.157
M3 - Article
C2 - 1750036
AN - SCOPUS:0026167713
VL - 164
SP - 157
EP - 167
JO - Tohoku Journal of Experimental Medicine
JF - Tohoku Journal of Experimental Medicine
SN - 0040-8727
IS - 2
ER -