Inclusion Criteria:  • Children 31 days through 26 years (inclusive) of age who undergo Trauma Red (highest level) activation or Trauma Level 1 (mid-level) activation at Children's Hospital Colorado or Children's National Medical Center.  Exclusion Criteria:  Pregnant patients Incarcerated patients Patients who object to study participation at any time Limited access to or compromised monitoring sites for non-invasive finger sensors Brain death (GCS 3 with fixed, dilated pupils)