Field Hypotension in Patients Who Arrive at the Hospital Normotensive: A Marker of Severe Injury or Crying Wolf?

Abstract

Trauma patients with hypotension in the field who arrive at a hospital with a normal blood pressure (BP) may not be recognized as significantly injured. Over a 5-year period, demographic, injury severity, and disposition data were retrospectively analyzed for patients > or =16 years of age with documented hypotension in the field (systolic BP < or =90 mm Hg) and normal BP (systolic BP >90 mmHg) on hospital arrival (hypotensive group). This group was compared to patients with normal BP in the field and on hospital arrival (normotensive group). During the study, 2207 patients with documented BP were transported directly from the scene. Of this number 44 (2%) were assigned to the hypotensive group, 2086 (94%) were assigned to the normotensive group, and 77 (4%) patients were hypotensive on hospital arrival. The hypotensive group had a systolic BP in the field of 70 +/- 26 mmHg compared to 140 +/- 26 mmHg in the normotensive group (p < 0.0001). Arrival BP at the hospital was normal in both groups. Compared to the normotensive group, the hypotensive group had higher Injury Severity Scores (22.0 vs. 11.1, p < 0.0001), lower Glasgow Coma Scores (10.8 vs. 14.0, p < 0.0001), lower Revised Trauma Scores (65 vs. 7.4, p < 0.0O01), more emergency department deaths (7% vs. 0%, p < 0.001), longer lengths of stay in the intensive care unit (8.6 vs. 7.0 days, p < 0.0001) and hospital (14.0 vs. 7.0 days, p < 0.0001), and increased hospital mortality (18% vs. 4%, p < 0.001). The retrospective design and exclusion of patients without documentation of BP in the field may have resulted in selection bias. Despite these limitations, field hypotension is a marker of significant injury in patients arriving at the hospital normotensive.