Do Autopsies Still Matter? The Influence of Autopsy Data on Final Injury Severity Score Calculations.

BACKGROUND: Despite a proven record of identifying injuries missed during clinical evaluation, the effect of autopsy on injury severity score (ISS) calculation is unknown. We hypothesized that autopsy data would alter final ISS and improve the accuracy of outcome data analyses. MATERIALS AND METHODS: All trauma deaths from January 2010 through June 2014 were reviewed. Trauma registrars calculated Abbreviated Injury Scale and ISS from clinical documentation alone. The most detailed available autopsy report then was reviewed, and AIS/ISS recalculated. Predictors of ISS change were identified using multivariate logistic regression. RESULTS: Seven hundred thirty-nine deaths occurred, of which 682 (92.3%) underwent autopsy (31% view-only, 3% with preliminary report, and 66% with full report). Patients undergoing full autopsy had a lower median age (39 versus 74 years, P < 0.01), a higher rate of penetrating injury (41.7% versus 0%, P < 0.01), and a higher emergency department mortality rate (30.8% versus 0%, P < 0.01) than those receiving view-only autopsy. Incorporating autopsy findings increased mean ISS (21.3 to 29.6, P < 0.001) and the percentage of patients with ISS ≥ 25 (49.9% to 69.2%, P < 0.001). Multivariate analysis identified length of stay, death in the emergency department, full rather than view-only autopsy, and presenting heart rate as variables associated with ISS increase. CONCLUSIONS: Autopsy data significantly increased ISS values for trauma deaths. This effect was greatest in patients who died early in their course. Targeting this group, rather than all trauma patients, for full autopsy may improve risk-adjustment accuracy while minimizing costs.

Prehospital end-tidal carbon dioxide is predictive of death and massive transfusion in injured patients: An Eastern Association for Surgery of Trauma multicenter trial.

BACKGROUND: Prehospital identification of the injured patient likely to require emergent care remains a challenge. End-tidal carbon dioxide (ETCO2) has been used in the prehospital setting to monitor respiratory physiology and confirmation of endotracheal tube placement. Low levels of ETCO2 have been demonstrated to correlate with injury severity and mortality in a number of in-hospital studies. We hypothesized that prehospital ETCO2 values would be predictive of mortality and need for massive transfusion (MT) in intubated patients. METHODS: This was a retrospective multicenter trial with 24 participating centers. Prehospital, emergency department, and hospital values were collected. Receiver operating characteristic curves were created and compared. Massive transfusion defined as >10 U of blood in 6 hours or death in 6 hours with at least 1 U of blood transfused. RESULTS: A total of 1,324 patients were enrolled. ETCO2 (area under the receiver operating characteristic curve [AUROC], 0.67; confidence interval [CI], 0.63-0.71) was better in predicting mortality than shock index (SI) (AUROC, 0.55; CI, 0.50-0.60) and systolic blood pressure (SBP) (AUROC, 0.58; CI, 0.53-0.62) (p < 0.0005). Prehospital lowest ETCO2 (AUROC, 0.69; CI, 0.64-0.75), SBP (AUROC, 0.75; CI, 0.70-0.81), and SI (AUROC, 0.74; CI, 0.68-0.79) were all predictive of MT. Analysis of patients with normotension demonstrated lowest prehospital ETCO2 (AUROC, 0.66; CI, 0.61-0.71), which was more predictive of mortality than SBP (AUROC, 0.52; CI, 0.47-0.58) or SI (AUROC, 0.56; CI, 0.50-0.62) (p < 0.001). Lowest prehospital ETCO2 (AUROC, 0.75; CI, 0.65-0.84), SBP (AUROC, 0.63; CI, 0.54-0.74), and SI (AUROC, 0.64; CI, 0.54-0.75) were predictive of MT in normotensive patients. ETCO2 cutoff for MT was 26 mm Hg. The positive predictive value was 16.1%, and negative predictive value was high at 98.1%. CONCLUSION: Prehospital ETCO2 is predictive of mortality and MT. ETCO2 outperformed traditional measures such as SBP and SI in the prediction of mortality. ETCO2 may outperform traditional measures in predicting need for transfusion in occult shock. LEVEL OF EVIDENCE: Diagnostic test, level III.

Effects of Early Altitude Exposure on the Open Abdomen After Laparotomy in Trauma.

INTRODUCTION: While damage control surgery and resuscitation techniques have revolutionized the care of injured service members who sustain severe traumatic hemorrhage, the physiologic and inflammatory consequences of hemostatic resuscitation and staged abdominal surgery in the face of early aeromedical evacuation (AE) have not been investigated. We hypothesized that post-injury AE with an open abdomen would have significant physiologic and inflammatory consequences compared to AE with a closed abdomen. MATERIALS AND METHODS: Evaluation of resuscitation and staged abdominal closure was performed using a murine model of hemorrhagic shock with laparotomy. Mice underwent controlled hemorrhage to a systolic blood pressure of 25 mmHg and received either no resuscitation, blood product resuscitation, or Hextend resuscitation to a systolic blood pressure of either 50 mmHg (partial resuscitation) or 80 mmHg (complete resuscitation). Laparotomies were either closed prior to AE (closed abdomens) or left open during AE (open abdomens) and subsequently closed. AE was simulated with a 1-hour exposure to a hypobaric hypoxic environment at 8,000 feet altitude. Mice were euthanized at 0, 4, or 24 hours following AE. Serum was collected and analyzed for physiologic variables and inflammatory cytokine levels. Samples of lung and small intestine were collected for tissue cytokine and myeloperoxidase analysis as indicators of intestinal inflammation. Survival curves were also performed. RESULTS: Unresuscitated mice sustained an 85% mortality rate from hemorrhage and laparotomy, limiting the assessment of the effect of simulated AE in these subgroups. Overall survival was similar among all resuscitated groups regardless of the presence of hypobaric hypoxia, type of resuscitation, or abdominal closure status. Simulated AE had no observed effects on acid/base imbalance or the inflammatory response as compared to ground level controls. All mice experienced both metabolic acidosis and an acute inflammatory response after hemorrhage and injury, represented by an initial increase in serum interleukin (IL)-6 levels. Furthermore, mice with open abdomens had an elevated inflammatory response with increased levels of serum IL-10, serum tumor necrosis factor alpha, intestinal IL-6, intestinal IL-10, and pulmonary myeloperoxidase. CONCLUSION: These results demonstrate the complex interaction of AE and temporary or definitive abdominal closure after post-injury laparotomy. Contrary to our hypothesis, we found that AE in those animals with open abdomens is relatively safe with no difference in mortality compared to those with closed abdomens. However, given the physiologic and inflammatory changes observed in animals with open abdomens, further evaluation is necessary prior to definitive recommendations regarding the safety or downstream effects of exposure to AE prior to definitive abdominal closure.

Proximal penetrating extremity injuries-An opportunity to decrease overtriage?

BACKGROUND: Penetrating injuries to the extremity proximal to the elbow or knee are anatomic criteria for full trauma team activation (FFTA) by the American College of Surgeon's Committee on Trauma standards. This criterion lacks objective evidence-based support. Overtriage of trauma team activation may result in excessive costs and resource burden at trauma centers. We hypothesized that FFTA for penetrating injuries to the proximal extremities by anatomic criteria alone may lead to significant overtriage. METHODS: A 3-year retrospective review (2013-2015) was completed of all patients evaluated at an urban Level I trauma center with isolated penetrating extremity injuries. Data included the number of full and limited trauma team activations as well as criterion met, Injury Severity Score (ISS), injury, limb characteristics, and disposition. Overtriage was defined as FFTA for an ISS of 15 or less, with a goal rate less than 50%. RESULTS: We identified 6,335 total trauma team activations with 795 isolated penetrating extremity injuries. Of these injuries, 413 (51.9%) were injuries proximal to the joint. Within this subgroup, 71.2% of patients were discharged from the emergency department with a median ISS of 1 and no additional intervention. Only 5.3% of patients that did not meet additional FFTA criteria underwent immediate operative intervention. By comparison, 21% of FFTAs and 5.8% of limited trauma team activations underwent immediate operative intervention during the 3-year period. Of the 413 isolated penetrating proximal-extremity injuries, only one had an ISS of 15 or greater, resulting in a 99.7% overtriage rate. CONCLUSION: Penetrating injuries to the extremities are common in urban trauma centers. Full trauma team activation based on anatomic, rather than physiologic, criteria may lead to a significant overtriage rate. Further distinction in the level of trauma team activation may be made based on hard signs of neurovascular injury. LEVEL OF EVIDENCE: Epidemiological study, level III; Care Management, level IV.