The relative vasodilating properties of isoproterenol, dopamine, and dobutomine on hypoxic pulmonary vasoconstriction were examined in isolated pig lungs, ventilated and perfused in situ. The flow-resistant properties of the pulmonary circulation were assessed by measuring the relationship between pulmonary arterial pressure (PAP) and flow (Q). Hypoxia ( a decrease in inspired O2 tension form 200 torr to 50 torr) caused a rightward shift and decreased in the slope of this relationship. This increase PAP an average of 18.8 torr when measured at a blood flow of 1 L/min. Isoproterenol and dobutamine inhibited hypoxic pulmonary vasoconstriction, whereas dopamine had no effect. Because of its relative freedom from adverse side-effects in clinical trials, dobutamine should be considered in patients with hypoxic pulmonary vasoconstriction and right heart failure.
ASJC Scopus subject areas
- Critical Care and Intensive Care Medicine