INHALED NITRIC-OXIDE PREVENTS EXPERIMENTAL PLATELET-ACTIVATING FACTOR-INDUCED SHOCK

Objective: To investigate whether inhaled nitric oxide (INO) can preve nt platelet activating factor (PAF)induced pulmonary hypertension and shock. Design: Randomized controlled animal trial. Setting: Laboratory . Subjects: Yorkshire swine. Interventions: Animals received general a nesthesia and invasive hemodynamic monitoring, then PAF only, 2.5 mu g /kg intravenously over 45 minutes (PAF group, n = 9) or PAF in additio n to INO, 20 ppm (PAF-INO group, n = 6). Main Outcomes: Vascular press ures (mean arterial and mean pulmonary), vascular resistance indexes ( systemic and pulmonary), cardiac indexes, and oxygen delivery and oxyg en consumption. Results: Mean arterial pressures, cardiac indexes, and oxygen delivery and consumption were significantly higher in the PAF- INO group. Mean pulmonary arterial pressures and systemic and pulmonar y vascular resistance indexes were significantly lower in the PAF-INO group. There were 4 deaths (44%) in the PAF group vs none (0%) in the PAF-INO group (P = .10). Conclusion: The use of INO prevents pulmonary hypertension, circulatory failure, and death during PAF-induced shock .