Craig Gravitz

Validation of the Simplified Motor Score in the Out-of-Hospital Setting for the Prediction of Outcomes After Traumatic Brain Injury

STUDY OBJECTIVE The Glasgow Coma Scale (GCS) score is widely used to assess patients with head injury but has been criticized for its complexity and poor interrater reliability. A 3-point Simplified Motor Score (SMS) (defined as obeys commands=2, localizes pain=1, and withdraws to pain or worse=0) was created to address these limitations. Our goal is to validate the SMS in the out-of-hospital setting, with the hypothesis that it is equivalent to the GCS score for discriminating brain injury outcomes. METHODS This was a secondary analysis of an urban Level I trauma registry. Four outcomes and their composite were studied: emergency tracheal intubation, clinically meaningful brain injury, need for neurosurgical intervention, and mortality. The out-of-hospital GCS score and SMS were evaluated by comparing areas under the receiver operating characteristic curve with a paired nonparametric approach. Multiple imputation was used for missing data. A clinically significant difference in areas under the receiver operating characteristic curve was defined as greater than or equal to 0.05, according to previous literature. RESULTS We included 19,408 patients, of whom 18% were tracheally intubated, 18% had brain injuries, 8% required neurosurgical intervention, and 6% died. The difference between the area under the receiver operating characteristic curve for the out-of-hospital GCS score and SMS was 0.05 (95% confidence interval [CI] -0.01 to 0.11) for emergency tracheal intubation, 0.05 (95% CI 0 to 0.09) for brain injury, 0.04 (95% CI -0.01 to 0.09) for neurosurgical intervention, 0.08 (95% CI 0.02 to 0.15) for mortality, and 0.05 (95% CI 0 to 0.10) for the composite outcome. CONCLUSION In this external validation, SMS was similar to the GCS score for predicting outcomes in traumatic brain injury in the out-of-hospital setting.

Prediction of postinjury multiple-organ failure in the emergency department: development of the Denver Emergency Department Trauma Organ Failure score.

BACKGROUND Multiple-organ failure (MOF) is common among the most seriously injured trauma patients. The ability to easily and accurately identify trauma patients in the emergency department at risk for MOF would be valuable. The aim of this study was to derive and internally validate an instrument to predict the development of MOF in adult trauma patients using clinical and laboratory data available in the emergency department. METHODS We enrolled consecutive adult trauma patients from 2005 to 2008 from the Denver Health Trauma Registry, a prospectively collected database from an urban Level 1 trauma center. Multivariable logistic regression was used to develop a clinical prediction instrument. The outcome was the development of MOF within 7 days of admission as defined by the Sequential Organ Failure Assessment (SOFA) score. A risk score was created from the final regression model by rounding the regression &bgr; coefficients to the nearest integer. Calibration and discrimination were assessed using 10-fold cross-validation. RESULTS A total of 4,355 patients were included in this study. The median age was 37 years (interquartile range [IQR], 26–51 years), and 72% were male. The median Injury Severity Score (ISS) was 9 (IQR, 4–16), and 78% of the patients had blunt injury mechanisms. MOF occurred in 216 patients (5%; 95% confidence interval, 4–6%). The final risk score included patient age, intubation, systolic blood pressure, hematocrit, blood urea nitrogen, and white blood cell count and ranged from 0 to 9. The prevalence of MOF increased in an approximate exponential fashion as the score increased. The model demonstrated excellent calibration and discrimination (calibration slope, 1.0; c statistic, 0.92). CONCLUSION We derived a simple, internally valid instrument to predict MOF in adults following trauma. The use of this score may allow early identification of patients at risk for MOF and result in more aggressive targeted resuscitation and improved resource allocation. LEVEL OF EVIDENCE Prognostic and epidemiologic study, level III.

Out-of-Hospital Cardiac Arrest in Denver, Colorado: Epidemiology and Outcomes

OBJECTIVES The annual incidence of out-of-hospital cardiac arrest (OOHCA) in the United States is approximately 6 per 10,000 population and survival remains low. Relatively little is known about the performance characteristics of a two-tiered emergency medical services (EMS) system split between fire-based basic life support (BLS) dispersed from fixed locations and hospital-based advanced life support (ALS) dispersed from nonfixed locations. The objectives of this study were to describe the incidence of OOHCA in Denver, Colorado, and to define the prevalence of survival with good neurologic function in the context of this particular EMS system. METHODS This was a retrospective cohort study using standardized abstraction methodology. A two-tiered hospital-based EMS system for the County of Denver and 10 receiving hospitals were studied. Consecutive adult patients who experienced nontraumatic OOHCA from January 1, 2003, through December 31, 2004, were enrolled. Demographic, prehospital arrest characteristics, treatment data, and survival data using the Utstein template were collected. Good neurologic survival was defined by a Cerebral Performance Categories (CPC) score of 1 or 2. RESULTS During the study period, 1,985 arrests occurred. Of these, 715 (36%) had attempted resuscitation by paramedics and constitute our study sample. The median age was 65 years (interquartile range = 52-78 years), 69% were male, 41% had witnessed arrest, 25% had bystander cardiopulmonary resuscitation (CPR) performed, and 30% had ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT) as their initial rhythm. Of the 715 patients, 545 (76%) were transported to a hospital, 223 (31%) had return of spontaneous circulation (ROSC), 175 (25%) survived to hospital admission, 58 (8%) survived to hospital discharge, and 42 (6%, 95% confidence interval [CI] = 4% to 8%) had a good neurologic outcome. CONCLUSIONS Out-of-hospital cardiac arrest survival in Denver, Colorado, is similar to that of other United States communities. This finding provides the basis for future epidemiologic and health services research in the out-of-hospital and ED settings in our community.

Safety of prehospital intravenous fentanyl for adult trauma patients.

BACKGROUND: Little is known about the safety of intravenous fentanyl for adult trauma patients in the prehospital setting. Our objective was to study the hemodynamic effect of prehospital intravenous fentanyl in initially normotensive adult trauma patients. METHODS: A quasi-experimental design was used to compare adult trauma patients who received intravenous fentanyl and those who did not receive fentanyl in a large regional prehospital system and its affiliated Level I trauma center. Emergent adult trauma patients were included with an initial prehospital Glasgow Coma Scale score of ≥13 and systolic blood pressure >90 mm Hg. Patients were stratified into two groups, those who received a single dose of intravenous fentanyl (100 &mgr;g) and those who did not. The outcome was initial emergency department (ED) shock index (heart rate divided by systolic blood pressure). Multivariable linear regression was used to estimate the effect of fentanyl on ED shock index while adjusting for prehospital shock index, age, gender, Trauma Injury Severity Score, and the propensity for receiving fentanyl. RESULTS: Seven hundred sixty-three patients were included, of whom 217 (28%) received fentanyl. The groups had comparable demographics (age, gender, and race/ethnicity) but different clinical characteristics (ED vital signs, Injury Severity Score, mechanism, and ED disposition). The adjusted ED shock index of fentanyl patients improved (-0.03; 95% confidence interval: −0.05 to 0.00; p = 0.02) compared with no fentanyl. CONCLUSION: Prehospital intravenous fentanyl did not adversely affect the initial ED shock index in adult trauma patients. Additional research should be performed to confirm and extend our findings. LEVEL OF EVIDENCE: III.

False-Negative FAST Examination: Associations With Injury Characteristics and Patient Outcomes

STUDY OBJECTIVE Focused assessment with sonography in trauma (FAST) is widely used for evaluating patients with blunt abdominal trauma; however, it sometimes produces false-negative results. Presenting characteristics in the emergency department may help identify patients at risk for false-negative FAST result or help the physician predict injuries in patients with a negative FAST result who are unstable or deteriorate during observation. Alternatively, false-negative FAST may have no clinical significance. The objectives of this study are to estimate associations between false-negative FAST results and patient characteristics, specific abdominal organ injuries, and patient outcomes. METHODS This was a retrospective cohort study including consecutive patients who presented to an urban Level I trauma center between July 2005 and December 2008 with blunt abdominal trauma, a documented FAST, and pathologic free fluid as determined by computed tomography, diagnostic peritoneal lavage, laparotomy, or autopsy. Physicians blinded to the study purpose used standardized abstraction methods to confirm FAST results and the presence of pathologic free fluid. Multivariable modeling was used to assess associations between potential predictors of a false-negative FAST result and false-negative FAST result and adverse outcomes. RESULTS During the study period, 332 patients met inclusion criteria. Median age was 32 years (interquartile range 23 to 45 years), 67% were male patients, the median Injury Severity Score was 27 (interquartile range 17 to 41), and 162 (49%) had a false-negative FAST result. Head injury was positively associated with false-negative FAST result (odds ratio [OR] 4.9; 95% confidence interval [CI] 1.5 to 15.7), whereas severe abdominal injury was negatively associated (OR 0.3; 95% CI 0.1 to 0.5). Injuries to the spleen (OR 0.4; 95% CI 0.24 to 0.66), liver (OR 0.36; 95% CI 0.21 to 0.61), and abdominal vasculature (OR 0.17; 95% CI 0.07 to 0.38) were also negatively associated with false-negative FAST result. False-negative FAST result was not associated with mortality (OR 0.89; 95% CI 0.42 to 1.9), prolonged ICU length of stay (relative risk 0.88; 95% CI 0.69 to 1.12), or total hospital length of stay (relative risk 0.92; 95% CI 0.76 to 1.12). However, patients with false-negative FAST results were substantially less likely to require therapeutic laparotomy (OR 0.31; 95% CI 0.19 to 0.52). CONCLUSION Patients with severe head injuries and minor abdominal injuries were more likely to have a false-negative than true-positive FAST result. On the other hand, patients with spleen, liver, or abdominal vascular injuries are less likely to have false-negative FAST examination results. Adverse outcomes were not associated with false-negative FAST examination results, and in fact patients with false-negative FAST result were less likely to have a therapeutic laparotomy. Further studies are needed to assess the strength of these findings.

Denver ED Trauma Organ Failure Score outperforms traditional methods of risk stratification in trauma

BACKGROUND Early identification of trauma patients at risk for inhospital mortality may facilitate goal-directed resuscitation and secondary triage to improve outcomes. The objective of this study was to compare prognostic accuracies of the Denver Emergency Department (ED) Trauma Organ Failure (TOF) Score, ED Sequential Organ Failure Assessment (SOFA) score, and ED base deficit and ED lactate for inhospital mortality in adult trauma patients. METHODS Consecutive adult trauma patients from 2005 to 2008 from the Denver Health Trauma Registry were included. Prognostic accuracies of the Denver ED TOF Score, ED SOFA score, ED base deficit, and ED lactate for inhospital mortality were evaluated with receiver operating characteristic curves. RESULTS Of the 4355 patients, the median age was 37 years (interquartile range [IQR], 26-51 years), median Injury Severity Score was 9 (IQR, 4-16), and 81% had blunt mechanisms. In addition, 38% (1670 patients) were admitted to the intensive care unit with a median intensive care unit length of stay of 2.5 days (IQR, 1-8 days), and 3% (138 patients) died. The areas under the receiver operating characteristic curves for the Denver ED TOF, ED lactate, ED base deficit, and ED SOFA were 0.94 (95% confidence interval [CI], 0.94-0.96), 0.88 (95% CI, 0.85-0.91), 0.82 (95% CI, 0.78-0.86), and 0.78 (95% CI, 0.73-0.82), respectively. CONCLUSIONS The Denver ED TOF Score more accurately predicts inhospital mortality in adult trauma patients compared to the ED SOFA score, ED base deficit, or ED lactate. The Denver ED TOF Score may help identify patients early who are at risk for mortality, allowing for targeted resuscitation and secondary triage to improve outcomes.