Safety Study of Nebulized Sodium Nitroprusside in Adult Acute Lung Injury

Acute lung injury (ALI) is caused by a wide variety of conditions, but always characterized by hypoxia and non-cardiogenic pulmonary edema. Current treatment of ALI is supportive and treatment of the underlying cause. New therapies to treat severe ALI have not been shown to improve survival, and are limited by financial and logistical resources. The investigators propose to investigate the role of inhaled sodium nitroprusside (iSNP) in ALI. Sodium nitroprusside (SNP) is a vasodilator. When inhaled, SNP may travel to areas of the lung participating in gas exchange, and cause the blood vessels surrounding these areas to enlarge. This may result in an increase of blood vessels to these areas of the lung, and improve oxygenation. Currently, iSNP has not been studied in the adult population. Therefore, this study is intended to find the safety profile of varying doses of iSNP.