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

Abstract

Introduction: 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.Methods: Over a 5-year period, demographic, injury severity, and disposition data were retrospectively analyzed for patients ≥16 years of age with documented hypotension in the field (systolic BP ≤ 90mmHg) and normal BP (systolic BP >90mmHg) on hospital arrival (hypotensive group). This group was compared to patients with normal BP in the field and on hospital arrival (normotensive group).Results: 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 vs14.0, p<0.0001), lower Revised Trauma Scores (6.5 vs 7.4, p<0.001), 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).Limitations: The retrospective design and exclusion of patients without documentation of BP in the field may have resulted in selection bias. Conclusion:Despite these limitations, field hypotension is a marker of significant injury in patients arriving at the hospital normotensive.