The utility of shock index in differentiating major from minor injury.

OBJECTIVE: The importance of early recognition of hemorrhagic shock and its effects on outcome have long been recognized. Traditional vital signs are relatively insensitive as early diagnostic markers of hemorrhage. The shock index (SI); heart rate (HR) divided by systolic blood pressure (SBP), has been suggested as such a marker. We tested the diagnostic utility of the SI in differentiating major from minor injury in trauma patients. METHODS: Retrospective study of a prospectively collected observational cohort at a level I trauma center. Demographics, injury mechanism, HR, SBP, base deficit and lactate were recorded and Injury Severity Score were calculated. Major injury was defined as either a change in hematocrit greater than 10 or blood transfusion requirement during initial 24 h, or Injury Severity Score greater than 15. RESULTS: One thousand four hundred and thirty-five trauma patients were enrolled, average age 35.2±16.9 years. Two hundred and forty-two were classified as major injury. The area under the receiver operator characteristic curves for SI [0.63 95% confidence interval (CI) 0.59-0.67] was significantly less than that for base deficit (0.72, 95% CI: 0.69-0.76) or lactate (0.69, 95% CI: 0.65-0.73). The diagnostic performance of SI was slightly better than HR (0.58) but not SBP (0.61). To reach sensitivity of 90%, the SI must be 0.5, well in the range of a normal SBP and HR. CONCLUSION: The SI can be a valuable tool, raising suspicion when it is abnormal even when other parameters are not, but is far too insensitive for use as a screening device to rule out disease. A normal SI should not lower the suspicion of major injury.

Triage hyperglycemia as a prognostic indicator of major trauma.

BACKGROUND: To test the diagnostic utility of the triage serum glucose in differentiating major from minor injuries. METHODS: Prospective database at Kings County Hospital, a Level I trauma center, from August 2005 to August 2008. INCLUSION CRITERIA: trauma patients 13+ years. EXCLUSION CRITERIA: diabetes or obvious life-threatening injuries requiring immediate surgery, isolated head trauma, or transferred or dead on arrival. We recorded age, sex, injury mechanism, base deficit (BD), lactate (LAC), and serum glucose and calculated Injury Severity Scores. Major injury: a change in hematocrit >10, blood transfused within 24 hours, or Injury Severity Score >15. Data were reported as mean differences (95% confidence interval [CI]). Groups were compared by Student's t test; receiver operator characteristic curves were compared by Wilcoxon test (two-tailed, [alpha] = 0.05). RESULTS: One thousand six hundred forty-nine patients with an average age of 35.5 years (13-95 years), 79.5% male, and 50% blunt trauma were studied. Patients with major (n = 278) compared with minor injury (n = 1371) had significantly (p < 0.0001) lower BD and higher LACs (p < 0.0001). Major injury patients had significantly (p < 0.0001) higher serum glucose levels (8.33 mMol/L, 95% CI: 7.94-8.69 mMol/L) compared with patients with minor injuries (6.49 mMol/L, 95% CI: 6.39-6.66 mMol/L). Areas under the curve for glucose (0.73, 95% CI: 0.70-0.76) are similar to BD (0.72, 95% CI: 0.68-0.76) and LAC (0.71, 95% CI: 0.67-0.75). CONCLUSIONS: Serum glucose was as discriminating as BD or LAC in differentiating minor from major injury. An initial glucose >/=11.1 mMol/L had a low sensitivity (15%) but a high specificity (94%) for major injury.

Simulation in a disaster drill: comparison of high-fidelity simulators versus trained actors.

OBJECTIVES: High-fidelity patient simulation provides lifelike medical scenarios with real-time stressors. Mass casualty drills must construct a realistic incident in which providers care for multiple injured patients while simultaneously coping with numerous stressors designed to tax an institution's resources. This study compared the value of high-fidelity simulated patients with live actor-patients. METHODS: A prospective cohort study was conducted during two mass casualty drills in December 2006 and March 2007. The providers' completion of critical actions was tested in live actor-patients and simulators. A posttest survey compared the participants' perception of "reality" between the simulators and live actor victims. RESULTS: The victims (n = 130) of the mass casualty drill all had burn-, blast-, or inhalation-related injuries. The participants consisted of physicians, residents, medical students, clerks, and paramedics. The authors compared the team's execution of the 136 critical actions (17 critical actions x 8 scenarios) between the simulators and the live actor-patients. Only one critical action was missed in the simulator group and one in the live actor group, resulting in a miss rate of 0.74% (95% confidence interval [CI] = 0.01% to 4.5%). All questionnaires were returned and analyzed. The vast majority of participants disagreed or strongly disagreed that the simulators were a distraction from the disaster drill. More than 96% agreed or strongly agreed that they would recommend the simulator as a training tool. The mean survey scores for all participants demonstrated agreement that the simulators closely mimicked real-life scenarios, accurately represented disease states, and heightened the realism of patient assessment and treatment options during the drill with the exception of nurse participants, who agreed slightly less strongly. CONCLUSIONS: This study demonstrated that simulators compared to live actor-patients have equivalent results in prompting critical actions in mass casualty drills and increase the perceived reality of such exercises.