Christoph R. Kaufmann

Hypothermic coagulopathy in trauma : Effect of varying levels of hypothermia on enzyme speed, platelet function, and fibrinolytic activity

BACKGROUND The coagulopathy noted in hypothermic trauma patients has been variously theorized to be caused by either enzyme inhibition, platelet alteration, or fibrinolytic processes, but no study has examined the possibility that all three processes may simultaneously contribute to coagulopathy, but are perhaps triggered at different levels of hypothermia. The purpose of this study was to determine whether, at clinically common levels of hypothermia (33.0-36.9 degrees C), there are specific temperature levels at which coagulopathic alterations are seen in each of these processes. METHODS Of 232 consecutive adult trauma patients presenting to a Level I trauma center, 112 patients met the inclusion criteria of an Injury Severity Score of 9 or greater and time since injury of less than 2 hours. Of the included patients, 40 were normothermic and 72 were hypothermic (> or =37 degrees C, n = 40; 36.9-36 degrees C, n = 29; 35.9-35 degrees C, n = 20; 34.9-34 degrees C, n = 16; 33.9-33 degrees C, n = 7). Included patients were prospectively studied with thrombelastography adjusted to core body temperature. Additionally, PT, aPTT, platelets, CO2, hemoglobin, hematocrit, and Injury Severity Score were measured. RESULTS Analysis by multivariate analysis of variance of the relationship between coagulation and temperature demonstrated that in hypothermic trauma patients, 34 degrees C was the critical point at which enzyme activity slowed significantly (p < 0.0001), and at which significant alteration in platelet activity was seen (p < 0.001). Fibrinolysis was not significantly affected at any of the measured temperatures (p > 0.25). CONCLUSIONS Patients whose temperature was > or =34.0 degrees C actually demonstrated a significant hypercoagulability. Enzyme activity slowing and decreased platelet function individually contributed to hypothermic coagulopathy in patients with core temperatures below 34.0 degrees C. All the coagulation measures affected are part of the polymerization process of platelets and fibrin, and this process may be the mechanism by which the alteration in coagulation occurs.

Advanced trauma life support, 8th edition, the evidence for change.

The American College of Surgeons Committee on Traumas Advanced Trauma Life Support Course is currently taught in 50 countries. The 8th edition has been revised following broad input by the International ATLS subcommittee. Graded levels of evidence were used to evaluate and approve changes to the course content. New materials related to principles of disaster management have been added. ATLS is a common language teaching one safe way of initial trauma assessment and management.

Usefulness of thrombelastography in assessment of trauma patient coagulation.

OBJECTIVE Thrombelastography (TEG) is used to rapidly assess coagulation abnormalities in cardiac and transplant surgery. The purpose of this study was to investigate TEG in the initial assessment of trauma patient coagulation. METHODS TEG was performed on 69 adult blunt trauma patients during their initial evaluation. Demographics, history of inherited coagulopathies, medications, TEG parameters, platelet count, prothrombin time/partial thromboplastin time, Revised Trauma Score (RTS), Injury Severity Score (ISS), use of blood products, and outcome were recorded. RESULTS Mortality was 4.3%. Fifty-two patients demonstrated coagulation abnormalities by TEG; of these, 45 were hypercoagulable (mean ISS 13.1), and seven were hypocoagulable (mean ISS 28.6). Six of the seven hypocoagulable patients received blood transfusions within the first 24 hours. Mean ISS of the 17 patients with normal TEG parameters was 3.7. Logistic regression of ISS, Revised Trauma Score, prothrombin time/partial thromboplastin time, and TEG on use/nonuse of blood products within the first 24 hours demonstrates that only ISS (p < 0.001) and TEG (p < 0.05) are predictive of early transfusion. CONCLUSIONS The majority of blunt trauma patients in this series were hypercoagulable. TEG is a rapid, simple test that can broadly determine coagulation abnormalities. TEG is an early predictor of transfusion in blunt injury patients.

Differences in mortality between elderly and younger adult trauma patients: geriatric status increases risk of delayed death.

BACKGROUND Elderly patients suffer higher mortality rates after trauma than younger patients. This increased mortality is attributable to age, preexisting disease, and complications as well as injury severity. METHODS Records from 5,139 adult patients from a Level I trauma center were retrospectively reviewed. Injury Severity Score (ISS), Revised Trauma Score (RTS), early mortality (<24 hours), and late mortality (>24 hours) were determined for elderly (> or =65 years) and younger (16-64 years) patients. Preexisting diseases and complications were identified by International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis coding. RESULTS Mortality in elderly patients was twice that in younger patients despite equivalent injury severity (p < 0.001), and elderly patients were more likely to suffer later death than younger patients (p < 0.005). The prevalence of preexisting disease was greater in the elderly, as was the incidence of complications. Using logistic regression, ISS, RTS, preexisting cardiovascular or liver disease, the development of cardiac, renal, or infectious complications, and geriatric status were all independently predictive of late mortality (p < 0.05). CONCLUSION Elderly trauma patients more frequently suffer late mortality than younger patients because of the combination of injury and increased preexisting disease and complications after injury. Aggressive treatment of the elderly trauma patient is warranted; however, in the face of significant preexisting disease or complications, survival is less likely. Predictive models of survival can be developed, taking into account preexisting disease and complications as well as admission parameters such as age, ISS, and RTS, and specific risk of mortality quantitated.

A population-based study of trauma recidivism

BACKGROUND Patients with repeat presentations to acute care hospitals for new injuries are trauma recidivists. Prospective identification of those patients at greatest risk will permit focusing of limited hospital prevention resources. METHODS A population-based analysis of patients with recurrent trauma presenting to all hospitals in Nevada during a 5-year period was conducted. Records of 10,355 presentations representing 10,137 patients were analyzed. RESULTS Recidivist trauma patients were younger than non-recidivists, with patients aged 20 to 24 years having significantly higher rates of recidivism. Males were 1.53 times more likely than females to become recidivists. Cutting/piercing and machinery-related injuries were most frequently associated with recidivism. Cutting/piercing wound survivors were 7.06 times more likely to be recidivists than were gunshot wound survivors. Recidivists in motor vehicles crashes were 1.92 times less likely to wear seat belts than nonrecidivists. Recidivism was also significantly associated with positive blood alcohol levels and longer initial hospital stays. CONCLUSION The rate of trauma recidivism in this study was 2.0%. Population-based data can be used to identify cohorts at risk of recidivism.

Windows 99: a source of suburban pediatric trauma

BACKGROUND Falls from windows in urban areas cause a significant number of pediatric injuries. Window falls have not been well described in the nonurban setting. We describe the epidemiology of window falls from residential homes among pediatric patients at a suburban Level I trauma center. METHODS A review of patients admitted from January 1991 through November 1999 to a center serving a rapidly growing suburban area was performed. RESULTS A total of 2,322 children, ages 0-14 years, were admitted during the study period. Falls comprised 41% of these admissions, and 11% of falls were from windows, greater than twice the national average. More than 39% of children who fell from windows were admitted directly to the intensive care unit. Overall mortality rate was 4%. Ages 0 to 4 years comprised the largest percentage (83%), and all children who died were in this age group. Children < or = 4 years were more likely to have an Abbreviated Injury Score > or = 2 (head injury) than those ages 10 to 14 years (p = 0.032). More than 31% of all children injured in window falls seen at the study institution between 1991 and 1999 were admitted in the last 2 years. CONCLUSION Pediatric falls from windows in this suburban area appear to be increasing, with an incidence greater than the national average. Children at greatest risk are less than 4 years old. Further research in injury prevention at the national level aimed at suburban areas may be warranted.

A reassessment of the impact of trauma systems consultation on regional trauma system development.

BACKGROUND Previous studies have shown that trauma systems decrease morbidity and mortality after injury, but progress in system development has been slow and inconsistent. This study evaluated the progress in 20 state or regional systems following a consultative visit conducted by the Trauma Systems Evaluation and Planning Committee (TSEPC) of the Committee on Trauma, expanding on a previous study published in 2008, which demonstrated significant progress in six systems following consultation. METHODS Twenty trauma systems that underwent TSEPC consultation between 2004 and 2010 were studied. Status was assessed using a set of 16 objective indicators. Baseline scores for 14 regions were calculated during the consultation visit and taken from the 2008 study for the remaining six. Postconsultation status was assessed during facilitated teleconferences. Progress was assessed by comparing changes in indicator scores. RESULTS There was significant improvement in approximately 80% of systems evaluated within 60 months following the consultation. There was no progress in five of six systems reevaluated over 80 months after consultation, and all four systems evaluated over 100 months after consultation showed erosion of progress. Significant improvements were seen in 10 of the 16 individual indicators, with the greatest gains related to system standards, data systems, performance improvement, prehospital triage criteria, and linkages with public health. Consistent with the 2008 study, the two indicators related to financing for the trauma system showed no improvement. CONCLUSION The TSEPC consultation process continues to be associated with improvements in trauma system development in approximately 80% of cases, consistent with the 2008 study, but gains are not self-sustaining. There was a stagnation in progress and a deterioration in total score over time, suggesting that a repeat consultation may be beneficial. System funding remains a challenge and was the area most likely to suffer setbacks over during study period. LEVEL OF EVIDENCE Care management study, level V.

Pediatric Trauma: Getting Triage Right-Reply

In Reply.— Dr Di Scala points out a valid concern. While overtriage is a resource utilization problem, undertriage resulting in inadequate medical care is important to the individual patient. This study used an Injury Severity Score of 15 as the indicator for appropriate triage in evaluating the Revised Trauma Score and the Pediatric Trauma Score as triage tools. Although an Injury Severity Score greater than 15 is often used as a proxy for severe injury and has been useful in evaluating populations of patients, this value is arbitrary and for an individual patient may either overestimate or underestimate the actual need for trauma center care. Other criteria of appropriate triage need to be developed. Examination of individual patients receiving undertriage by the Revised Trauma Score but not by the Pediatric Trauma Score may demonstrate that some of these patients did not actually need trauma center care as evaluated by other