Corticosteroid by aerosol in septic pigs--effects on pulmonary function and oxygen transport.

Abstract

To assess effects of nebulized corticosteroid on lung function in sepsis. Randomized, placebo-controlled, blinded study in septic pigs. A trauma research laboratory. 16 juvenile pigs, one excluded due to pulmonary hypertension at baseline. Mechanical ventilation and continuous light anesthesia. Brief infusion of live Staph. aureus (4 x 10(10) cfu) followed by nebulization of beclomethasone dipropionate (BDP) 50 micrograms/kg (n = 8) or placebo (n = 7) 30 and 360 min after start of septic challenge. Vascular pressures, cardiac output, lung mechanics, gas exchange and oxygen transport variables were measured at regular intervals. An identical transient rise in mean pulmonary artery pressure was seen in both groups (mean +/- SD: 48 +/- 4 mmHg), followed by a gradual increase in pulmonary vascular resistance, reaching maximum at 4 h but significantly reduced by BDP compared to placebo (p < 0.01, ANOVA). Mean systemic arterial pressure, arterial oxygen tension and lung compliance did not change significantly in the BDP group, but they all declined in the placebo-group (p < 0.01 compared to baseline, p < 0.05-0.01 between the groups). Oxygen delivery decreased significantly in the placebo group at 12 h (p < 0.05). Oxygen extraction increased in both groups (p < 0.01 compared to baseline), being significantly higher in the placebo group at 12 h (p < 0.05). Nebulized corticosteroid protects pulmonary function in sepsis, indicating a therapeutic role in the treatment of septic ARDS.