Muscle Oxygen Saturation Might Help Identify Trauma Patients with Severe Hemorrhage

Researchers assessed whether the addition of muscle oxygen saturation (SmO₂) to vital signs improves early (before other diagnostic tests are available) identification of trauma patients with major hemorrhage. In an observational study at a Level I trauma center, the researchers analyzed mean muscle oxygen saturation (monitored with near-infrared spectrometry [NIRS]), heart rate, pulse pressure, and systolic blood pressure monitored over a 10-minute period early in patients' emergency department evaluation.

Of 487 adult patients (68% men) enrolled over a 2-year span, 23 received 3 or more units of red blood cells within 24 hours (primary outcome) and 11 received 9 or more units. In multivariate regression models, addition of SmO₂ to the vita…