It is generally accepted that patients with a systolic blood pressure (SBP)<90 mmHg are in "shock" and have a worse prognosis than patients with a higher SBP. Our objective was to determine if patients with a SBP of 90-109 mmHg have a worse outcome than patients with a higher SBP following trauma. Patients with gastric, small bowel, and/or diaphragm injuries were identified retrospectively through the trauma database from 1980-2003. All 2071 patients underwent emergent laparotomy at an urban, level one trauma center. The mortality rate of patients with a SBP of 90-109 mmHg in the ED or OR was 5% (17/354) and significantly higher than the 1% (12/1020) mortality seen in patients with a SBP of 110 mmHg or greater (P<0.001). The average length of stay of patients with a SBP of 90-109 mmHg was 15+/-14 days and was significantly longer than the 11+/-11 days seen in patients with a higher SBP. If the SBP was 90-109 mmHg, the infection rate was 39% (131/340), and this was significantly higher than the 22% (219/1016) infection rate seen in patients with higher SBP (P<0.001). Trauma patients with a systolic blood pressure of 109 mmHg or below are at increased risk for morbidity and mortality following trauma. Patients with a systolic blood pressure of 90-109 mmHg following trauma should be considered as a special group requiring aggressive resuscitation and surgery. Early operative control of hemorrhage in these patients can reduce mortality and infection.