LIFE-THREATENING EFFECTS OF DISCONTINUING INHALED NITRIC-OXIDE IN CHILDREN

We treated 40 children, aged between 15 d and 17 y, diagnosed with acu te respiratory distress syndrome and/or pulmonary hypertension, with i nhaled nitric oxide. The most frequent underlying diagnosis associated with ARDS were bronchopneumonia (eight), cardiac surgery (five), and sepsis (three). Pulmonary hyper tension was secondary to cardiomyopath y in 2 patients and occurred in the postoperative period of cardiac su rgery in 17 patients-the most frequent were ventricular septal defect (5), transposition of great arteries (4), and atrioventricular septal defect (3). In 11 patients, sudden discontinuation of nitric oxide ind uced a decrease in oxygenation associated in some of the patients with an increase in pulmonary artery pressure. In two patients discontinua tion of nitric oxide induced severe pulmonary hypertension, extreme br adycardia and hypoxaemia, which required cardiopulmonary resuscitation . When exogenous nitric oxide is abruptly interrupted, hypoxaemia and pulmonary hypertension are found in some patients, due to a decrease i n the nitric oxide concentration in the pulmonary circulation. This ma y be caused by the exogenous nitric oxide administration that may have inhibited endogenous production. We recommend making a progressive wi thdrawal of inhaled nitric oxide to avoid the side effects observed in the sudden discontinuation.