Safety Study of Inhaled Carbon Monoxide to Treat Pneumonia and Sepsis-Induced Acute Respiratory Distress Syndrome (ARDS)

ARDS is a syndrome of severe acute lung inflammation and hypoxemic respiratory failure with an incidence of 180,000 cases annually in the United States. Despite recent advances in critical care management and lung protective ventilation strategies, ARDS morbidity and mortality remain unacceptably high. Furthermore, no specific effective pharmacologic therapies currently exist. Sepsis, life-threatening organ dysfunction caused by a dysregulated host response to infection, represents a major risk for the development of ARDS and multi-organ dysfunction syndrome (MODS). In recent years, the number of patients with severe sepsis has risen to 750,000 per year in the U.S., which bears an alarming forecast for critically ill patients in the intensive care unit with significant risk for the development of ARDS. The lack of specific effective therapies for ARDS indicates a need for new treatments that target novel pathways. Carbon monoxide (CO) represents a novel therapeutic modality in sepsis-induced ARDS based on data obtained in experimental models of sepsis and ARDS over the past decade. CO has been shown to be protective in experimental models of acute lung injury (ALI) and sepsis. Furthermore, multiple human studies have demonstrated that experimental administration of several different concentrations of CO is well-tolerated and that low dose inhaled CO can be safely administered to subjects in a controlled research environment. The investigators have previously conducted a Phase I trial of low dose iCO in sepsis-induced ARDS which demonstrated that precise administration of low dose iCO (100 and 200 ppm) is feasible, well-tolerated, and safe in patients with sepsis-induced ARDS. The purpose of this study is to assess the safety and accuracy of a CFK equation-based iCO personalized dosing algorithm of inhaled carbon monoxide (iCO) to achieve a target COHb level of 6-8% in mechanically ventilated patients with sepsis-induced ARDS.