Effect of mean airway pressure on bronchial mucosal blood flow in rabbits with oleic acid-induced injury.
The effects of mean airway pressure (MAP) on bronchial mucosal blood flow at the carina in nine anesthetized adult rabbits undergoing high frequency ventilation were studied. The animals were given oleic acid to diminish lung compliance and to exclude the influences of increasing MAP on systemic venous return. Mucosal blood flow decreased significantly when MAP exceeded 14 cmH2O. Mucosal blood velocity tended to decrease as higher levels of MAP were applied. Mucosal blood volume decreased significantly when MAP exceeded 20 cmH2O. Hemodynamics, arterial blood gas values and pH were not changed significantly. Our data demonstrate that bronchial mucosal blood flow decreases at high levels of MAP even if cardiac output remains constant. Hence this decrease of bronchial mucosal blood flow may be due to the transmission of pressure to submucosal bronchial capillaries.
Mizuno
K
K
Department of Pediatrics, Showa University School of Medicine, Tokyo, Japan.
Itabashi
K
K
Okuyama
K
K
D000818:Animals; D001980:Bronchi / Q000098:blood supply*; D006612:High-Frequency Ventilation / Q000009:adverse effects; D007511:Ischemia / Q000209:etiology; D008170:Lung Compliance / Q000187:drug effects; D009092:Mucous Membrane / Q000098:blood supply; D019301:Oleic Acid; D009829:Oleic Acids; D011312:Pressure / Q000009:adverse effects; D011817:Rabbits; D012039:Regional Blood Flow; D012119:Respiration / Q000502:physiology*
D009829:Oleic Acids; D019301:Oleic Acid