Effects of nitroprusside on lung mechanics and hemodynamics after endotoxemia in awake sheep

NARD. Effects of nitroprusside on lung mechanics and hemody-numics after endotoxemia in awake sheep. J. Appl. Physiol. 64(5): 2026-2032, 1988.-We examined the effects of intrave-nous sodium nitroprusside (NP) infusion on pulmonary arterial pressure (Ppa), pulmonary vascular resistance (PVR), dynamic compliance (Cdyn), resistance to airflow across the lungs ( RL), and alveolar-arterial O2 pressure gradient (PA*,- Pao,) (room air) after endotoxemia in awake sheep. NP infused 2.5 h after endotoxin administration immediately reduced mean Ppa from 30 + 3 to 17 t 3 (SE) cmHzO, PVR from 6.3 t 0.7 to 4.8 t 0.5-cmHnO l-‘. min, and RL from 340 t 48 of base line to 205 & 73 % and increased Cdyn from 54 & 5 of base line to 80 t 14% without affecting PAN,- Pao,. Ppa and lung mechanics re-turned immediately to preinfusion levels when NP was stopped. In vitro experiments with NP showed a dose-dependent relax