Lynn G. Stansbury

Trauma mortality in mature trauma systems: are we doing better? An analysis of trauma mortality patterns, 1997-2008.

BACKGROUND Advances in care such as damage control surgery, hemostatic resuscitation, protocol-driven cerebral perfusion management, and lung-protective ventilation have promised to improve survival after major trauma. We examined injury severity, mortality, and preventability in a mature trauma system during a 12-year period to assess the overall benefits of these and other improvements. METHODS Using the institutional trauma registry and the quality management database, we analyzed the outcome and the cause of death for all primary trauma admissions from July 1, 1996, to June 30, 2008, and linked these data with patient demographics, hospital length of stay, time to death, predicted probability of survival, and peer review of in-hospital deaths. RESULTS Through fiscal year (FY) 2007, primary trauma admissions increased in number, injury severity, and age. Performance benchmarked against predicted probability of survival improved. Mortality through this era ranged from 3% to 3.7% and worsened slightly overall (p = 0.04). However, among those patients admitted with Injury Severity Score 17-25, survival improved significantly (p = 0.0003). Traumatic brain injury (TBI) accounted for 51.6% of deaths; acute hemorrhage, 30%; and multiple organ failure, 10.5%. Median time to death for uncontrollable hemorrhage, TBI, multiple organ failure was 2 hours, 24 hours, and 15 days, respectively. These patterns did not change significantly over time. CONCLUSION Survival after severe trauma and survival benchmarked against predicted risk improved significantly at our center during the past 12 years despite generally increasing age and worsening injuries. Advances in trauma care have kept pace with an aging population and greater severity of injury, but overall survival has not improved.

Amputations in U.S. military personnel in the current conflicts in Afghanistan and Iraq

Objectives: To determine rates of major limb amputation in U.S. military casualties in the current conflicts in Afghanistan and Iraq, to correlate these with mechanism of injury, and compare the rate with that seen in U.S. casualties from the Vietnam War. Design: Retrospective study of all U.S. casualties recorded for the current conflicts from the start in October 1, 2001 to June 1, 2006. Setting: Records from U.S. military forward surgical teams (Level IIb) and combat support hospitals (Level III) in theater, evacuation (Level IV, Germany), and major military medical centers (Level V, United States). Patients/Participants: All recorded U.S. military casualties from the Afghanistan and Iraq theaters with injuries requiring evacuation out of theater or prohibiting the individual from returning to duty for more than 72 hours. Intervention: None. Main Outcome Measurements: Major limb injury, level of amputation, principal mechanism of injury. Results: Over the past 56 months, of the 8058 military casualties meeting the listed criteria, 5684 (70.5%) were recorded as having major limb injuries. Of these, 423 (5.2% of all serious injuries; 7.4% of major limb injuries) underwent major limb amputation or amputation at or proximal to the wrist or ankle joint. The mechanism of injury for 87.9% was some form of explosive device. The major amputation rate during Vietnam was 8.3% of major limb injuries. Conclusions: Overall, major limb amputation rates for the current U.S. engagement in Afghanistan and Iraq are similar to those of previous conflicts.

The prevalence of abnormal results of conventional coagulation tests on admission to a trauma center

BACKGROUND: Several groups have reported that a fraction of severely injured patients have abnormal coagulation tests at presentation to trauma centers, even in the absence of significant crystalloid resuscitation. These patients have high mortality, but their prevalence in trauma populations is not clear from the reports.

Blood product use in trauma resuscitation: plasma deficit versus plasma ratio as predictors of mortality in trauma (CME)

BACKGROUND: Resuscitation of rapidly bleeding trauma patients with units of red blood cells (RBCs) and plasma given in a 1:1 ratio has been associated with improved outcome. However, demonstration of a benefit is confounded by survivor bias, and past work from our group has been unable to demonstrate a benefit.

Controversy in Trauma Resuscitation: Do Ratios of Plasma to Red Blood Cells Matter?

Since a report in October 2007 of dramatic improvements in trauma mortality in a military population when massive transfusion of red blood cells (RBC) was accompanied by plasma replacement at 1:1 proportions, interest in the plasma-to-RBC ratio during resuscitation in both the trauma and transfusion communities has been intense. Over the 7-month period from August 2008 through February 2009, a further 9 major studies examining experience with plasma replacement in massively transfused civilian trauma patients have been published. This flood of observational studies is likely to continue. In this review, the authors examine the findings of these initial studies, highlighting the epidemiologic and analytic methodologies used, and the likely influence of these methodologies on the reported outcomes.

Heart rate and pulse pressure variability are associated with intractable intracranial hypertension after severe traumatic brain injury.

Calculation of integer heart rate variability (HRVi) permits monitoring over extended periods. We asked whether continuous monitoring of HRVi or integer pulse pressure (PP) variability (PPVi) could predict intracranial hypertension, defined as ICP >20 mm Hg, cerebral hypoperfusion, defined as CPP<60 mm Hg, mortality or functional outcome after severe traumatic brain injury. Dense integer data collected during continuous intensive care unit monitoring for periods of 1 to 11 days on 25 patients admitted to our Level I trauma center with Glasgow Coma Scale <9 provided 1,715,000 data points over a mean 106±62 hours. PP, HRVi, and PPVi increased in response to increasing ICP when CPP >60 mm Hg (P<0.001), but HRVi and PPVi decreased when CPP <60 mm Hg and P<50 mm Hg, even with ICP <20 mm Hg (P<0.001). ICP up to 40 mm Hg still evoked an increase in HRVi and PPVi (P<0.001), but both were suppressed with CPP <50 mm Hg and ICP >40 mm Hg (actual or impending brain death). Mean HRVi and PPVi predicted in-hospital mortality (sensitivity, 67%; specificity, 91% to 100%). Combining HRVi and PPVi as an “autonomic index” (AI) best predicted long-term functional outcome [Area Under the Curve: 0.84±0.08 for AI <0.5]. Our data show that HRVi and PPVi can be monitored and calculated automatically and can provide useful prognostic information in patients with severe traumatic brain injury, particularly when combined into a single index.

The clinical significance of platelet counts in the first 24 hours after severe injury

BACKGROUND: Admission platelet (PLT) counts are known to be associated with all‐cause mortality for seriously injured patients admitted to a trauma center. The course of subsequent PLT counts, their implications, and the effects of PLT therapy are less well known.

Impediments to Obtaining Informed Consent for Clinical Research in Trauma Patients

BACKGROUND Informed consent is required for, but a substantial barrier to, clinic research in trauma care. Exceptions have been established but remain controversial, and little objective data are available to illuminate this debate. METHODS We prospectively assessed 2,011 consecutive patients admitted to the R Adams Cowley Shock Trauma Center of the University of Maryland Medical System for the potential to give consent for a hypothetical research trial within 1 hour of admission or whether consent could be obtained from a legally authorized representative (LAR) within 3 hours. These data were then linked with demographic, transport, physiologic, and injury data. RESULTS Complete data were available for 1,734 patients: 982 (57%) appeared able to consent and 752 (43%) appeared unable to consent. Of the latter, LAR consent was potentially available for 404, leaving 348 (46%, 20% of all admissions) unconsentable. Those apparently able to consent were significantly less injured than those unable, but a third were subsequently found to have objective barriers to giving consent, and a further third had findings strongly suggestive of impairment. For those unable to consent, subsequent LAR consent was strongly associated with being a minor or being a woman. Lack of LAR consent was strongly associated with being the victim of intentional injury, with being an African-American male and-for European-American men only-with being transported greater distances. CONCLUSIONS Severely injured trauma patients can seldom provide consent for research studies, and LARs are often unavailable. Further efforts to develop workable mechanisms for exception from informed consent are justified.

Blood Transfusion in World War I: The Roles of Lawrence Bruce Robertson and Oswald Hope Robertson in the “Most Important Medical Advance of the War”

The demonstration and acceptance of the life-saving potential of blood transfusion in the resuscitation of combat casualties came in two parts. First, Canadian surgeon Major Lawrence Bruce Robertson showed that direct transfusion of uncrossmatched blood from the veins of a donor to a patient could save the lives of many moribund casualties, even if a few died of acute hemolytic reactions. Second, US Army Captain Oswald Hope Robertson showed that stored, syphilis-tested, universal donor whole blood could be given quickly and safely in forward medical units. With these demonstrations, the Royal Army Medical Corps adopted transfusion and declared it the most important medical advance of the war.

Forward Surgical Teams provide comparable outcomes to combat support hospitals during support and stabilization operations on the battlefield.

BACKGROUND Forward Surgical Teams (FST) provide forward deployed surgical care within the battle space. The next level of care in theater, the Combat Support Hospitals (CSH), are distinguished from the FST by advanced resource capabilities including more complex diagnostic imaging, laboratory support with blood banking, and intensive care units. This study was intended to assess the effect of FST capability on the outcome of seriously injured casualties in comparison to the CSH. METHODS We reviewed all casualty records in the Joint Theater Trauma Registry database from April 2004 to April 2006. The study cohort included all US military battle casualties who were admitted to either a FST or a CSH and were not returned to duty within 72 hours. Data were tabulated and assessed for basic demographics, mechanism of injury, injury severity score, ventilator and critical care days, and mortality. Statistical inferences were made using Chi square and Students t tests. RESULTS As of April 2006, the above information was available in the Joint Theater Trauma Registry on 2,617 US military battle casualties who survived to reach care at a FST and/or CSH. Of this population, 77 subsequently died of wounds and 2,540 survived. We found no significant difference in died of wounds rates between the sample populations or rates of ventilator or critical care days between the two groups, nor did controlling for injury severity score alter this picture. The most significant predictor of mortality in both these groups was head injury. CONCLUSIONS The disparity between the availability of the highest level of injury care and the ability to care for injury as soon as possible is an issue of central importance to both the civilian and military trauma care communities. Our analysis demonstrates that despite the operational and logistic challenges that burden the FST, this level of surgical care confers equivalent battlefield injury outcome results compared with the CSH.