DOES NOREPINEPHRINE MODIFY THE EFFECTS OF INHALED NITRIC-OXIDE IN SEPTIC PATIENTS WITH ACUTE RESPIRATORY-DISTRESS SYNDROME

Background: Hypoxia-related pulmonary vasoconstriction enhanced by nor epinephrine could be deleterious in patients with the acute respirator y distress syndrome (ARDS) and sepsis. A prospective study compared th e effects of nitric oxide on cardiorespiratory parameters, including t he evaluation of right ventricular function in patients with ARDS and sepsis who were receiving or not receiving norepinephrine. Methods: Du ring a 15-month period, 27 patients with ARDS and sepsis were prospect ively investigated (group 1: 15 patients not receiving norepinephrine; group 2: 12 patients receiving norepinephrine). Right ventricular eje ction fraction was measured by thermodilution. After baseline measurem ents, nitric oxide was administered at increasing inspiratory concentr ations. Results: The ratio of oxygen tension in arterial blood to the fractional concentration of oxygen in inspired gas increased in the tw o groups. After logarithmic transformation of the data, an analysis of variance was performed that did not show any difference between the t wo groups. A dose-dependent decrease in mean pulmonary arterial pressu re was observed in the two groups. This decrease and the increase in r ight ventricular ejection fraction induced by inhaled nitric oxide wer e more marked when patients received norepinephrine (P < 0.0001). Conc lusion: Norepinephrine did not influence the beneficial effects of inh aled nitric oxide administered to patients with ARDS and sepsis on oxy genation.