Anaphylactic shock in monkeys passively sensitized with human reaginic serum. II. Respiratory mechanics, hematology and metabolism.

Seven monkeys were passively sensitized intravenously (i.v.) with human serum containing IgE antibodies specific to dog albumin. I.v. administration of the antigen resulted in an immediate increase in pulmonary resistance (Rpulm) with a concomitant decrease in pulmonary dynamic compliance (Cdyn). Initially these changes in the respiratory system resulted in pronounced effects on venous admixture, arterial oxygen saturation (SaO2) and arterial pH. After 30 min, as Rpulm and Cdyn returned towards control levels, the blood gas changes were mainly due to low cardiac output. There was a transient increase in hematocrit, a decrease in plasma fibrinogen and a transient reduction in the number of circulating leukocytes. The anaphylactic reaction resulted in a 10- to 30-fold increase in plasma adrenaline with time and in a substantial but less marked increase in plasma noradrenaline and dopamine. Probably as a consequence of the increase in plasma catecholamine, there was a rise in plasma cyclic AMP, glucose and glycerol. No increase in plasma histamine levels was found. In two animals sensitized with purified IgE a reaction which was less severe but had the same general pattern was observed. The findings show that IgE-mediated anaphylaxis in the monkey results in a bronchoconstriction leading to a profound respiratory disturbance characterized by decreased SaO2 due to increased venous admixture. After 30 min these variables were normalized and the shock state was dominated by poor tissue perfusion due to a low cardiac output.