Inhaled nitric oxide: clinical applications

Abstract

Up to a decade ago, nitric oxide (NO) was viewed primarily as a toxic gas responsible for a portion of the morbidity related to air pollution. In contrast, NO currently is recognised as a major endogenous mediator of an extraordinary range of functions including vascular regulation, neurotransmission, host defence and cytotoxicity. An increasing volume of literature has shown the importance of NO in the regulation of various cardiopulmonary functions and suggested its involvement in several disease processes. There is now compelling experimental evidence suggesting that inhaled NO may be beneficial in disease states characterised by pulmonary vasoconstriction and ventilationperfusion mismatch. 1 Several diseases of newborns and older children are characterised by potentially life threatening hypoxaemia due to ventilation-perfusion mismatch in the lungs associated with pulmonary vasoconstriction and pulmonary hypertension. Inhaled NO therapy may prove beneficial in a number of these conditions.