Macrophage Programing in Acute Lung Injury: MiniBAL

This research study is looking at the role of white blood cells in acute respiratory distress syndrome (ARDS). ARDS is a severe, life-threatening disease caused by uncontrolled inflammation in the lungs. Macrophages are a type of white blood cell that is involved in both causing and removing inflammation. The goal of this study is to learn more about macrophages in the setting of ARDS, so that the investigators can potentially find new treatments for this disease. To get the best information for this study, macrophages from patients with ARDS will be compared to macrophages from individuals with healthy lungs. All participants in this study must be on a breathing machine (mechanical ventilator). Participants must either have damage to the lungs (ARDS) or have healthy lungs with no prior history of lung disease. Participants must fit into one of these categories. For this study, the investigators will isolate macrophages from a sample of fluid obtained from the lungs. While the method used to obtain the sample of fluid is a standard procedure performed in the ICU, the investigators will be performing it for research purposes. The investigators will also be collecting two nasal brushes. During the nasal brushing a small brush will be inserted into the first one or two inches of the participants nasal cavity from the participants nostril by a member of the research team. The brush will be moved back and forth gently, then removed. A second brush will be inserted in the other nostril and the technique repeated. A second part of our study is to determine whether regularly sampling fluid from the lungs and looking for bacteria will help us catch and treat pneumonia quicker. As such, a portion of the fluid obtained from the lungs, will be sent to the laboratory to look for bacteria growing in the lung.