Effect of experimental biliary obstruction on respiratory function

Abstract

Since liver damage due to alcoholic cirrhosis and viral hepatitis may influence respiration, we have studied biliary obstruction in the rat to see if this form of liver damage could also influence respiratory function. Three weeks after sham surgery or common bile duct division, the effect of liver damage on red cell morphology, red cell 2,3-diphosphoglycerate, blood gases with room air and 100% and 10% oxygen, respiratory rate, oxygen consumption, blood ammonia and pulmonary morphology were studied. Experimental biliary obstruction was associated with impaired weight gain, hypoxemia, respiratory alkalosis, intrapulmonary shunting of blood, elevated arterial but not venous ammonia, decreased oxygen consumption, elevated venous lactate, normal pulmonary diffusion of oxygen, microscopic abnormalities of the lung, and a macrocytic anemia. Histological examination of the lung revealed thickening of the alveolar septal walls with proliferation of alveolar cells and increased content of collagen. The anemia was unaffected by splenectomy and folic acid but the macrocytosis was corrected by folic acid. Hyperventilation may have been related to the elevated arterial ammonia, hypoxia and possible abnormal circulatory metabolic degradation products. The hypoxia was due to intrapulmonary shunting of blood. The anemia appeared unrelated to hypersplenism and only modified by folic acid.