Twenty-five to 30 per cent of hypotensive trauma patients require an emergent surgery, however, we have no reliable means to quickly determine that need. Our goal was to determine, via retrospective review, parameters available within minutes of arrival that predict the need for emergent surgery to control hemorrhage in hypotensive trauma patients. Inclusion criterion was initial systolic blood pressure (SBP) < 90 mm Hg in the emergency department (ED). Patients who were dead on arrival or underwent ED thoracotomy were excluded. Emergent surgery was defined as sternotomy, thoracotomy, laparotomy, or major neck vascular repair on day of admission. Potential clinical predictors were analyzed in a binary logistic regression model. Six hundred and thirty-nine hypotensive patients were identified and 193 excluded, leaving 446 with a mean age of 33 +/- 19 years and Injury Severity Score of 22 +/- 17. Thirty-two per cent suffered penetrating trauma, 30 per cent needed emergent surgery, and 19 per cent died. Independent predictors were: prolonged extrication (odds ratio (OR) 2.3), no loss of consciousness (OR 2.8), intubation (OR 1.7), central line placement (OR 1.7), and blood transfusion (OR 2.1, all P < 0.05). We concluded that hypotensive trauma patients without head injuries who require prolonged extrication, intubation, central venous access, and blood transfusion in the ED are more likely to need emergent surgery.