(370009-43) Strategy to Avoid Excessive Oxygen in Critically Ill Trauma Patients: A Multicenter Randomized Trial

Introduction: Administering supplemental oxygen to prevent and treat hypoxemia can expose patients to excess inspired oxygen and hyperoxemia (SpO2>96%), which have unknown clinical consequences. We sought to determine the effectiveness and safety of targeting normoxemia (SpO2 90-96%) to conserve oxygen and improve clinical outcomes in critically ill trauma patients.

Methods: We conducted a multicenter cluster-randomized, stepped-wedge trial comparing an oxygenation strategy that targeted normoxemia to usual care in adult trauma patients admitted to an intensive care unit [NCT04534959]. We randomized eight Level 1 trauma centers across the U.S. to cross over from pre-implementation (usual care) to post-implementation (targeting normoxemia) at three-month intervals. The intervention involved a multimodal educational and informatics program targeting normoxemia and down-titrating supplemental oxygen in patients with an SpO2>96%. The primary outcome was supplemental oxygen-free days, defined as the number of days alive and not receiving supplemental oxygen through day 28.

Results: We enrolled 13,903 patients (mean age 52 years, 32% female, 70% blunt injury, median injury severity score 17, 29% mechanically ventilated at baseline) between July 15, 2020, and November 14, 2022. Hypoxemia was overall rare; 0.7% of patient time was spent in hypoxemia in both the pre- and post-implementation periods. The number of supplemental oxygen-free days was significantly greater in the post-intervention group (mean 20.9, standard deviation 9.2) than in the pre-intervention group (mean 19.3, standard deviation 9.8) (adjusted mean difference, 1.7 days; 95% CI 1.1-2.4; P< 0.001). Results were similar for mechanically ventilated patients and non-mechanically ventilated patients (P value for interaction=0.68). By day 90, 715 patients (9.6%) from the pre-intervention phase and 463 patients (8.8%) from the post-intervention phase had died before hospital discharge.

Conclusions: Among critically ill trauma patients, targeting normoxemia increased the number of supplemental oxygen-free days without increasing exposure to hypoxemia.