DAMP-Mediated Innate Immune Failure and Pneumonia After Trauma - the Harvard-Longwood (HALO) Campus Area Consortium

The purpose of the interventional group is to address Aim 3 of this research study. Aim 3 will be accomplished by randomizing eligible patients to normoxic or hyperoxic conditions with normocarbic or hypercarbic blood concentrations through ventilator adjustments per the factorial design. All four groups are considered within the bounds of standard practice for many mechanically ventilated patients. Investigators will exclude patients in whom these settings could be detrimental. The patient will be on the study settings by hour 60 of mechanical ventilation, and these settings will be held for 48 hours from achieving the target partial pressure of oxygen (PaO2) levels. Upon enrollment, an arterial line will be placed if there is not already one in place, and an arterial blood gas (ABG) will be drawn if no ABG has been drawn in the prior 12 hours to enrollment. Over 1-3 hours following ventilator adjustments, several ABGs will be drawn in order to determine the need for additional ventilator adjustments. Foreseeable adjustments include changes to FiO2, respiratory rate, and tidal volume. Once the desired PaO2 level is achieved ("time 0"), investigators will obtain an ABG q12 hours throughout the 48 hour interventional period. After maintaining the ventilator settings for 48 hours, ventilator management will revert to the clinical team. Blood and bronchoalveolar lavage (BAL) will be collected from the patient at time of enrollment.