ARDS is a serious condition that involves inflammation and fluid accumulation in the lungs, leading to low blood oxygen levels and breathing failure. It is often fatal and affects approximately 150,000 individuals each year in the United States. Common underlying causes include bacterial infections, lung trauma, and pneumonia. Even in people with similar risk factors for ARDS, there are often varying levels of condition severity. This may be because some people experience an ongoing viral infection that further predisposes them to the bacterial infection, worsening the severity of ARDS. Viruses release a protein called Type I interferon. This protein increases the response of the interferon stimulated genes (ISG) in neutrophils, which are white blood cells that protect the body against disease and infections by destroying bacteria. Preliminary studies have shown that some people at risk for ARDS have elevated ISGs in their neutrophils and that ISGs are associated with an impaired neutrophil response and increased severity of ARDS. This study will evaluate the association between viral-related neutrophil ISG response and the severity of ARDS.
Participants will include people on mechanical ventilation who are enrolled in either the ARDSNet 06 or 07 studies. For this study, participants will undergo blood collection within 48 hours of beginning the main ARDSNet study. There will be no study visits specifically for this study. Study researchers will analyze participants' blood samples and ARDSNet study data to gather information on mortality, the number of ventilator-free days, markers of severity of organ dysfunction and inflammation, and neutrophil response.