Lethal injuries and time to death in a level I trauma center

Increased Lactate Levels Impair the Coagulation System—A Potential Contributing Factor to Progressive Hemorrhage After Traumatic Brain Injury

Progressive intracerebral contusions are a major problem in the management of patients with severe traumatic brain injury that is also linked to worse outcome. Microdialysis studies have revealed that lactate levels are very high inside contusions, corresponding to significant acidosis. The current study was performed in an effort to investigate whether the lactate accumulation inside cerebral contusions may be a contributing factor to the prolonged bleeding inside contusions. We have investigated the effects of lactic acidosis on the coagulation system with rotational thromboelastometry. It was a laboratory study involving 6 healthy volunteers. Blood was drawn and the pH was adjusted by addition of lactic acid in vitro. The pH levels studied were 7.4, 7.2, 7.0, and 6.8. The pH was also readjusted to 7.4 by addition the buffer THAM to blood initially adjusted to a pH of 6.8 to study the reversibility of potential adverse effects induced by the lactic acidosis. We found the coagulation to be significantly impaired by lactic acidosis (P = 0.000l). The impairment found was reversible after correction of the acidosis by a buffer. In conclusion, we found that lactic acidosis impaired the coagulation system. The impairment caused by lactic acidosis may be one factor causing the progressive hemorrhage in posttraumatic cerebral contusions, known to have high levels of lactate and correspondingly low pH. It may also be important to consider in bleeding trauma patients.

Are we the problem? Overcoming obstacles to implementing intervention programs

Alcohol-related injuries comprise a large percentage of injuries in the United States. As the impact of these injuries on society increases, a well-functioning trauma system becomes increasingly important. During the last decade, evidence-based guidelines to reduce alcohol-related injuries have emerged. Further, evidence supports the effectiveness of brief intervention programs to reduce alcohol-related injuries and demonstrates that trauma centers can improve patient outcomes by integrating them into care. Although many obstacles have inhibited progress and made implementing preventive interventions a difficult task, economic constraints are among the biggest challenges to implementing intervention programs as part of routine trauma care.

A systematic review of brain injury epidemiology in Europe

BACKGROUND

The world's literature on traumatic brain injury (TBI) grows annually including new reports on epidemiologic findings from many regions. With the wide variety of reports emphasizing various factors it is useful to compile these findings, hence the objective of this report. Thus, we describe epidemiological factors from European studies largely published in the last 20 years.

METHOD

The Medline was searched for TBI related articles from about 1980 to 2003 including terms such as "epidemiology", "head injury", "brain injury" and others. From the research reports identified, we checked references for additional relevant reports and from those reports we abstracted data on TBI incidence, severity, external cause, gender, mortality, prevalence, cost and related factors.

RESULTS

Twenty three European reports met inclusion criteria and included findings from national studies from Denmark, Sweden, Finland, Portugal, Germany, and from regions within Norway, Sweden, Italy, Switzerland, Spain, Denmark, Ireland, the U.K. and France. An aggregate hospitalized plus fatal TBI incidence rate of about 235 per 100,000 was derived. Prevalence rate data were not reported from any European country. An average mortality rate of about 15 per 100,000 and case fatality rate of about 11 per 100 were derived. The TBI severity ratio of hospitalized patients was about 22:1.5:1 for mild vs. moderate vs. severe cases, respectively. The percentages of TBI from external causes varied considerably and several reports reported an association of alcohol use with TBI. Outcome or disability findings were mixed and inconsistent.

INTERPRETATION

It was difficult to reach a consensus on all epidemiological findings across the 23 published European studies because of critical differences in methods employed across the reports. We highly recommend the development of research guidelines to standardize definitional, case finding, and data reporting parameters to help establish a more precise description and hence utility of the epidemiology of TBI in Europe.

The Effect of Fibrinogen Substitution on Reversal of Dilutional Coagulopathy: An In Vitro Model

Colloids and crystalloids are usually administered as treatment for hypovolemia in severely injured patients. However, dilution of clotting factors and platelets together with impaired fibrinogen polymerization are associated with fluid therapy and may aggravate hemorrhage, thus worsening final outcome of these patients. We investigated, in an in vitro model, whether the addition of fibrinogen to diluted blood samples can reverse dilutional coagulopathy. Blood from 5 healthy male volunteers was diluted by 60% using lactated Ringer's solution, 4% modified gelatin solution, or 6% hydroxyethyl starch 130/0.4, as well as the combination of lactated Ringer's solution with either of the 2 colloid solutions. Thereafter, aliquots of diluted blood samples were incubated with 3 different concentrations of fibrinogen (0.75, 1.5, and 3.0 mg/mL). Measurements were performed by modified thrombelastography (ROTEM; Pentapharm, Munich, Germany). After 60% dilution, clotting times increased, whereas clot firmness and fibrin polymerization decreased significantly. After administration of fibrinogen, clotting times decreased and clot firmness, as well as fibrin polymerization, increased in all diluted blood samples. The effect of in vitro fibrinogen substitution on ROTEM variables was dependent on the fibrinogen dosage and the type of solution used to dilute the blood samples.

Does the Rate of Rewarming from Profound Hypothermic Arrest Influence the Outcome in a Swine Model of Lethal Hemorrhage?

BACKGROUND

Rapid induction of profound hypothermic arrest (suspended animation) can provide valuable time for the repair of complex injuries and improve survival. The optimal rate for re-warming from a state of profound hypothermia is unknown. This experiment was designed to test the impact of different warming rates on outcome in a swine model of lethal hemorrhage from complex vascular injuries.

METHODS

Uncontrolled lethal hemorrhage was induced in 40 swine (80-120 lbs) by creating an iliac artery and vein injury, followed 30 minutes later (simulating transport time) by laceration of the descending thoracic aorta. Through a thoracotomy approach, a catheter was placed in the aorta and hyperkalemic organ preservation solution was infused on cardiopulmonary bypass to rapidly (2 degrees C/min) induce profound (10 degrees C) hypothermia. Vascular injuries were repaired during 60 minutes of hypothermic arrest. The 4 groups (n = 10/group) included normothermic controls (NC) where core temperature was maintained between 36 to 37 degrees C, and re-warming from profound hypothermia at rates of: 0.25 degrees C/min (slow), 0.5 degrees C/min (medium), or 1 degrees C/min (fast). Hyperkalemia was reversed during the hypothermic arrest period, and blood was infused for resuscitation during re-warming. After discontinuation of cardiopulmonary bypass, the animals were recovered and monitored for 6 weeks for neurologic deficits, cognitive function (learning new skills), and organ dysfunction. Detailed examination of brains was performed at 6 weeks.

RESULTS

All the normothermic animals died, whereas survival rates for slow, medium and fast re-warming from hypothermic arrest were 50, 90, and 30%, respectively (p < 0.05 slow and medium warming versus normothermic control, p < 0.05 medium versus fast re-warming). All the surviving animals were neurologically intact, displayed normal learning capacity, and had no long-term organ dysfunction.

CONCLUSIONS

Rapid induction of hypothermic arrest maintains viability of brain during repair of lethal vascular injuries. Long-term survival is influenced by the rate of reversal of hypothermia.

A portable cardiopulmonary bypass/extracorporeal membrane oxygenation system for the induction and reversal of profound hypothermia: feasibility study in a Swine model of lethal injuries

The Cleveland Clinic Foundation's (CCF) cardiopulmonary bypass/extracorporeal membrane oxygenation (CPB/ECMO) system capabilities were tested in a hypothermia trauma management feasibility study in a porcine animal model at the Uniformed Services University of the Health Sciences (USUHS, Bethesda, MD, U.S.A.). In this survival series, the CCF system was used in a simulated forward lines combat casualty application where lethal uncontrolled hemorrhage from major vascular injuries was repaired under a state of profound hypothermic arrest (suspended animation), followed by recovery and monitoring in an intensive care unit (ICU) setting. The animals were monitored for survival, neurological impact, cognitive functions, organ damage, and delayed complications over 3 weeks. A survival rate of 83% matched rates previously found using conventional equipment. Neurological findings, organ dysfunction, and complication rates also were no different from previous studies using standard equipment. Successful survival results demonstrated that the CCF CPB/ECMO system could be used to induce a period of profound hypothermic arrest for the repair of lethal traumatic injuries. The logistical advantages of this system make it an attractive choice for use in austere settings and during transport.

The epidemiology and modern management of traumatic hemorrhage: US and international perspectives

Trauma is a worldwide problem, with severe and wide ranging consequences for individuals and society as a whole. Hemorrhage is a major contributor to the dilemma of traumatic injury and its care. In this article we describe the international epidemiology of traumatic injury, its causes and its consequences, and closely examine the role played by hemorrhage in producing traumatic morbidity and mortality. Emphasis is placed on defining situations in which traditional methods of hemorrhage control often fail. We then outline and discuss modern principles in the management of traumatic hemorrhage and explore developing changes in these areas. We conclude with a discussion of outcome measures for the injured patient within the context of the epidemiology of traumatic injury.

Combat casualty care research: from bench to the battlefield

Hemorrhagic shock is the leading cause of death in civilian and combat trauma. Effective hemorrhage control and better resuscitation strategies have the potential of saving lives. The Trauma Readiness and Research Institute for Surgery (TRRI-Surg) was established to address the core mission of the Uniformed Services University, "Learning to Care for Those in Harm's Way," by conducting research to improve the outcome of combat casualties. This article highlights the salient achievements of this research effort in the areas of hemorrhage control, resuscitation, design and testing of devices, and some novel concepts such as the use of profound hypothermia. The impact of these basic science research findings on changes in military medical care and outcome of injured soldiers is also described.

Pathophysiology of polytrauma

Immediate and early trauma deaths are determined by primary brain injuries, or significant blood loss (haemorrhagic shock), while late mortality is caused by secondary brain injuries and host defence failure. First hits (hypoxia, hypotension, organ and soft tissue injuries, fractures), as well as second hits (e.g. ischaemia/reperfusion injuries, compartment syndromes, operative interventions, infections), induce a host defence response. This is characterized by local and systemic release of pro-inflammatory cytokines, arachidonic acid metabolites, proteins of the contact phase and coagulation systems, complement factors and acute phase proteins, as well as hormonal mediators: it is defined as systemic inflammatory response syndrome (SIRS), according to clinical parameters. However, in parallel, anti-inflammatory mediators are produced (compensatory anti-inflammatory response syndrome (CARS). An imbalance of these dual immune responses seems to be responsible for organ dysfunction and increased susceptibility to infections. Endothelial cell damage, accumulation of leukocytes, disseminated intravascular coagulation (DIC) and microcirculatory disturbances lead finally to apoptosis and necrosis of parenchymal cells, with the development of multiple organ dysfunction syndrome (MODS), or multiple organ failure (MOF). Whereas most clinical trials with anti-inflammatory, anti-coagulant, or antioxidant strategies failed, the implementation of pre- and in-hospital trauma protocols and the principle of damage control procedures have reduced post-traumatic complications. However, the development of immunomonitoring will help in the selection of patients at risk of post-traumatic complications and, thereby, the choice of the most appropriate treatment protocols for severely injured patients.

Deep Venous Thrombosis and Pulmonary Embolism in Trauma Patients: An Overstatement of the Problem?

Deep venous thrombosis (DVT) and pulmonary embolism (PE) affect high-risk trauma patients (HRTP). Accurate incidence and clinical importance of DVT and PE in HRPT may be overstated. We performed a ten-year retrospective analysis of HRTP of the Pennsylvania Trauma Outcome Study. High-risk factors (HRF) included pelvic fracture (PFx), lower extremity fracture (LEFx), severe head injury (CHI) (AIS – head ≥3), and spinal cord injury. HRF alone or in combination, age, Injury Severity Score (ISS), and Glasgow Coma Score (GCS) were examined for association with DVT/PE. A total of 73,419 HRTP were included: 1377 (1.9%) had DVT, 365 (0.5%) had PE. The incidence of DVT in level I trauma centers was 2.2 per cent and was 1.5 per cent in level II centers. The lowest incidence of DVT was 1.3 per cent for isolated LEFx; highest was 5.4% for combined PFx, LEFx, and CHI. Variables associated with DVT included age, ISS, and GCS (all P < 0.001). In logistic regression analysis, only ISS was consistently predictive for DVT and PE. Though increased during the past decade, the overall incidence of DVT in HRTP remains below 3 per cent. Only the combination of multiple injuries or an ISS >30 result in DVT incidence of ≥5 per cent. We believe that current guidelines for screening for DVT may need to be reevaluated.

Pediatric trauma in southwestern Ontario: linking data with injury prevention initiatives

BACKGROUND

Our objective was to provide an epidemiologic description of pediatric trauma in SW Ontario using multiple data sets. Injury prevention (IP) initiatives were linked with predominant injury mechanisms to determine whether IP programs were supported by data.

METHODS

Descriptive analysis was undertaken for five pediatric age groups (<1 year, 1-4 years, 5-9 years, 10-14 years, 15-19 years) using the Ontario Trauma Registry's Death Data Set, Comprehensive Data Set (Lead Trauma Hospitals [LTH] patients), and Minimal Data Set (hospital admissions), 1999-2000, for all pediatric patients residing in SW Ontario. National Ambulatory Care Reporting System (NACRS) data from the Children's Hospital of Western Ontario/London Health Sciences Centre were used to capture the Emergency Room (ER) injury data. Information on IP initiatives for children and youth was gathered through an Internet search, supplemented by a survey.

RESULTS

Injury in SW Ontario resulted in 13,197 ER visits, 1,616 hospital admissions, 70 severe trauma (ISS > 12) cases treated at a LTH and 47 deaths to children and youth. More males than females were injured, with the sex differential more pronounced as age increased. Falls were the leading mechanism for ER visits (37%) and hospital admissions (26%). Recreational injuries represented approximately 30% of injuries to the 10-14 yr age group. As ISS increased, MVCs emerged as an important mechanism, representing 71% of LTH cases and 53% of pediatric injury deaths in SW Ontario. There were 61 pediatric IP programs identified in SW Ontario. Eighty-four percent of programs (51/61) were supported by data, and were related to one of the predominant injury mechanisms.

CONCLUSIONS

Injury is a serious problem for children in SW Ontario. Data can be used to identify modifiable risk factors to develop and implement new IP initiatives with the goal of reducing childhood injury and death. There is a need to integrate and link IP programs in SW Ontario for full coverage of all injury mechanisms.

Surgical Complications and Causes of Death in Trauma Patients that Require Temporary Abdominal Closure

Temporary abdominal closure (TAC) has increasingly been employed in the management of severely injured patients to avoid abdominal compartment syndrome (ACS) and as part of damage control surgery (DCS). Although the use of TAC has received great interest, few data exist describing the morbidity and mortality associated with its use in trauma victims. The main goal of this study is to describe the incidence of surgical complications following the use of TAC as well as to define the mortality associated with this procedure. A retrospective review of patients admitted to a state-designated level 1 trauma center from April 2000 to February 2003 was performed. Inclusion criteria were age >18 years, traumatic injury, and need for exploratory laparotomy and use of TAC. A total of 120 patients were included in the study. The overall mortality of trauma patients requiring TAC was 59.2 per cent. The most common causes of death were acute inflammatory process (50.7%), followed by hypovolemic shock (43.7%). The incidence of surgical complications was 26.6 per cent. Intra-abdominal abscesses were the most frequent surgical complication (10%). After multiple logistic regression analysis, increasing age and a numerically greater initial base deficit were found to be independent predictors of mortality in trauma patients that require TAC.

Recombinant factor VIIa for the treatment of severe postoperative and traumatic hemorrhage

BACKGROUND

The aim of this study was to determine the dose of recombinant factor VIIa (rFVIIa) that has been used in our institution to successfully control hemorrhage in trauma and postoperative patients.

METHODS

This was an 8-month retrospective cohort study of 13 patients with acute hemorrhage and no known history of coagulopathic disorders.

RESULTS

Administration of factor VIIa resulted in the cessation of life-threatening hemorrhage at dosages approximately one half those recommended for the management of hemophilia. After administration, there was a significant decrease in the total blood-product transfusion requirement (P <0.05).

CONCLUSIONS

The use of factor VIIa in patients with life-threatening hemorrhage is a safe and effective therapeutic modality when used as an adjunct to standard interventions for control of severe hemorrhage. Lower-dose regimens were as successful as higher-dose regimens previously reported. The results of this respective study of 13 patients suggests that recombinant factor VIIa therapy for control of life-threatening hemorrhage as an adjunct to standard interventions can be successful at doses <90 mg/kg.

Appropriate use of helicopters to transport trauma patients from incident scene to hospital in the United Kingdom: an algorithm

A simple algorithm has been produced to assist front line ground ambulance personnel, air ambulance crews, and immediate care doctors attending trauma patients in selecting the most appropriate mode of transport from the incident scene to hospital.

An in vitro evaluation of standard rotational thromboelastography in monitoring of effects of recombinant factor VIIa on coagulopathy induced by hydroxy ethyl starch

Background

Rotational thromboelastography (ROTEG) has been proposed as a monitoring tool that can be used to monitor treatment of hemophilia with recombinant factor VIIa (rFVIIa). In these studies special non-standard reagents were used as activators of the coagulation. The aim of this study was to evaluate if standard ROTEG analysis could be used for monitoring of effects of recombinant factor VIIa (rFVIIa) on Hydroxy Ethyl Starch-induced dilutional coagulopathy.

Methods

The study was performed in vitro on healthy volunteers. Prothrombin time (PT) and ROTEG analysis were performed after dilution with 33% hydroxy ethyl starch and also after addition of rFVIIa to the diluted blood.

Results

PT was impaired with INR changing from 0.9 before dilution to 1.2 after dilution while addition of rFVIIa to diluted blood lead to an overcorrection of the PT to an International Normalized Ratio (INR) value of 0.6 (p = 0.01). ROTEG activated with the contact activator ellagic acid was impaired by hemodilution (p = 0.01) while addition of rFVIIa had no further effects. ROTEG activated with tissue factor (TF) was also impaired by hemodilution (p = 0.01) while addition of rFVIIa lead to further impairment of the coagulation (p = 0.01).

Conclusions

The parameters affected in the ROTEG analysis were Clot Formation Time and Amplitude after 15 minutes while the Clotting Time was unaffected. We believe these effects to be due to methodological problems when using standard activators of the coagulation in the ROTEG analysis in combination with rFVIIa.

Thrombocytopenia Predicts Progressive Hemorrhage after Head Trauma

Patients with traumatic brain injury (TBI) often show progression of hemorrhagic injuries (PHI) after admission to the hospital. This progression is correlated with poor outcome. In this study, we have investigated if thrombocytopenia was a risk factor for PHI. The study was performed on patients admitted to the hospital with severe TBI during year 2000. In total, 50 patients were admitted with severe TBI. Twenty-seven out of these had complete platelet counts at admission and 24 hours thereafter and were included for further study. We found thrombocytopenia at admission to be a risk factor for PHI (p=0.008). We also found that the platelet count decreased more significantly during the first 24 h after injury in patients with PHI compared to patients without PHI (p=0.009). A trend towards longer periods of mechanical ventilation in patients with PHI compared to patients without PHI was identified. These findings support a causal relationship between thrombocytopenia and PHI. The findings provide a rationale for future studies of hemostatic agents in the treatment of TBI in order to minimise complications caused by PHI.

Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy

This article discusses the prevention of venous thromboembolism (VTE) and is part of the Seventh American College of Chest Physicians Conference on Antithrombotic and Thrombolytic Therapy: Evidence-Based Guidelines. Grade 1 recommendations are strong and indicate that the benefits do, or do not, outweigh risks, burden, and costs. Grade 2 suggests that individual patients' values may lead to different choices (for a full understanding of the grading see Guyatt et al, CHEST 2004; 126:179S-187S). Among the key recommendations in this chapter are the following. We recommend against the use of aspirin alone as thromboprophylaxis for any patient group (Grade 1A). For moderate-risk general surgery patients, we recommend prophylaxis with low-dose unfractionated heparin (LDUH) (5,000 U bid) or low-molecular-weight heparin (LMWH) [< or = 3,400 U once daily] (both Grade 1A). For higher risk general surgery patients, we recommend thromboprophylaxis with LDUH (5,000 U tid) or LMWH (> 3,400 U daily) [both Grade 1A]. For high-risk general surgery patients with multiple risk factors, we recommend combining pharmacologic methods (LDUH three times daily or LMWH, > 3,400 U daily) with the use of graduated compression stockings and/or intermittent pneumatic compression devices (Grade 1C+). We recommend that thromboprophylaxis be used in all patients undergoing major gynecologic surgery (Grade 1A) or major, open urologic procedures, and we recommend prophylaxis with LDUH two times or three times daily (Grade 1A). For patients undergoing elective total hip or knee arthroplasty, we recommend one of the following three anticoagulant agents: LMWH, fondaparinux, or adjusted-dose vitamin K antagonist (VKA) [international normalized ratio (INR) target, 2.5; range, 2.0 to 3.0] (all Grade 1A). For patients undergoing hip fracture surgery (HFS), we recommend the routine use of fondaparinux (Grade 1A), LMWH (Grade 1C+), VKA (target INR, 2.5; range, 2.0 to 3.0) [Grade 2B], or LDUH (Grade 1B). We recommend that patients undergoing hip or knee arthroplasty, or HFS receive thromboprophylaxis for at least 10 days (Grade 1A). We recommend that all trauma patients with at least one risk factor for VTE receive thromboprophylaxis (Grade 1A). In acutely ill medical patients who have been admitted to the hospital with congestive heart failure or severe respiratory disease, or who are confined to bed and have one or more additional risk factors, we recommend prophylaxis with LDUH (Grade 1A) or LMWH (Grade 1A). We recommend, on admission to the intensive care unit, all patients be assessed for their risk of VTE. Accordingly, most patients should receive thromboprophylaxis (Grade 1A).

Application of a Granular Mineral-Based Hemostatic Agent (QuikClot) to Reduce Blood Loss After Grade V Liver Injury in Swine

BACKGROUND

Uncontrolled hemorrhage is a leading cause of death in cases of trauma. Many products currently are under development to control traumatic bleeding. One such Food and Drug Administration (FDA)-approved product is QuikClot. This study determined the efficacy of QuikClot, a hemostatic agent, in reducing blood loss and mortality in a standardized model of severe liver injury as well as the consequences of its use.

METHODS

Swine received either QuikClot or gauze treatment after induction of grade V liver injuries. Hemostasis, blood loss, resuscitation volume, 60-minute survival, and peak tissue temperatures were measured.

RESULTS

Hemostasis was improved with QuikClot (p < 0.05), and resuscitation volume was consequently reduced (p < 0.05). Posttreatment blood loss was reduced (p < 0.01) with QuikClot (1,397 mL), as compared with gauze (5,338 mL). The survival rate was seven of eight in the QuikClot group and one of eight in the gauze group (p < 0.01). Peak temperature at the tissue interface was increased (p < 0.01) with QuikClot (93.3 +/- 10.5 degrees C), as compared with gauze (37.5 +/- 6.5 degrees C). QuikClot use was associated with both macro- and microscopic tissue damage caused by the exothermic reaction.

CONCLUSION

QuikClot provides hemostasis and decreased mortality in this model of severe liver injury. The beneficial aspects of QuikClot treatment must, however, be balanced against the tissue-damaging effects of the exothermic reaction.

SURVIVAL IN A RAT MODEL OF LETHAL HEMORRHAGIC SHOCK IS PROLONGED FOLLOWING RESUSCITATION WITH A SMALL VOLUME OF A SOLUTION CONTAINING A DRAG-REDUCING POLYMER DERIVED FROM ALOE VERA

Drag-reducing polymers (DRP) increase tissue perfusion at constant driving pressure. We sought to evaluate the effects of small-volume resuscitation with a solution containing a DRP in a rat model of hemorrhage. Anesthetized rats were hemorrhaged at a constant rate over 25 min. In protocol A, total blood loss was 2.45 mL/100 g, whereas in protocol B, total blood loss was 3.15 mL/100 g. Five minutes after hemorrhage, the animals were resuscitated with 7 mL/kg of either normal saline (NS) or NS containing 50 microg/mL of an aloe vera-derived DRP. In protocol B, a third group (CON) was not resuscitated. Whole-body O2 consumption (Vo2) and CO2 production (Vco2) were measured using indirect calorimetry. In protocol A, 5/10 rats in the NS group and 8/10 rats in the DRP group survived for 4 h (P = 0.14). Mean arterial pressure was higher in the DRP-treated group than in the NS-treated group 45 min after resuscitation (89 +/- 8 vs. 68 +/- 5 mmHg, respectively; P < 0.05). In protocol B, survival rates over 2 h in the DRP, NS, and CON groups were 5/15, 1/14, and 0/7, respectively (P < 0.05). Compared with NS-treated rats, those resuscitated with DRP achieved a higher peak Vo2 (9.0 +/- 1.0 vs. 6,3+/- 1.0 mL/kg/min) and Vco2 (9.0 +/- 1.1 vs. 6.0 +/- 1.0 mL/kg/min) after resuscitation. We conclude that resuscitation with a small volume of DRP prolongs survival in rats with lethal hemorrhagic shock.

Bystander trauma care—effect of the level of training

BACKGROUND

The bystander is often the first person present at the scene of an accident. Our aim was to determine how often and how well bystanders perform trauma care and whether trauma care is affected by the bystander's level of training, relationship to the patient and numbers of bystanders present.

PATIENTS AND METHODS

In a prospective 1-year study, the emergency medical service in two European cities collected data on trauma calls. Questionnaires were used to document the bystanders' level of training (none, basic, advanced, professional), the bystander's relationship to the patient, and the number of bystanders present, and to assess whether five separate measures of trauma care (ensuring scene safety, extrication of the patient, positioning, control of haemorrhage, prevention of hypothermia) were performed correctly, incorrectly, or not at all.

RESULTS

Two thousand nine hundred and thirty-two trauma calls were documented and bystanders were present in 1720 (58.7%). All measures except ensuring scene safety and prevention of hypothermia were affected by the bystander's level of training. Correct extrication, positioning, and control of haemorrhage increased with the level of bystander training while the number of patients who were not attended decreased (P < 0.05, P < 0.005, P < 0.005), respectively. The relationship to the patient did not affect whether, or how well, any measure was performed. The number of bystanders present only affected prevention of hypothermia, which was performed most often when only one bystander was present.

CONCLUSION

Improved, more widespread training could increase the frequency and quality of bystander trauma care further.

The epidemiology of serious and fatal injury in San Diego County over an 11-year period

BACKGROUND

Analysis of the mechanism and severity of injury over time may permit a more focused planning of acute care and trauma prevention programs.

METHODS

A retrospective, population-based study examining severe traumatic injury in a single county was undertaken. Three overlapping data sets were used to form a composite injury data set.

RESULTS

There were 55,664 patients included in the study. A total of 40,897 (73.5%) patients survived and 14,767 (26.5%) died. Of those patients who died, 8,910 (60.3%) died in the field and were not transported to a trauma center. There was an increase in the mean age of all trauma victims (3 years) and an increase of 5 years in fatally injured patients. The mean Injury Severity Score decreased from 14.7 to 11.6 (p < 0.01); however, Injury Severity Score for fatal patients remained constant (39.7). The overall injury rate remained unchanged (195 per 10(5)), whereas the fatal injury rate decreased by 22% (45.9 per 10(5)) over the 11-year study period. The leading cause of injury was motor vehicle crash, followed by assault. The leading cause of fatal injury was suicide, followed by homicide.

CONCLUSION

A combination of three independent injury data sources generated a composite data set of serious and fatal injury. This regional injury analysis was the most comprehensive overview of injury in our region. Important observations included the following: there has been no change in the overall incidence of severe injury within our county; the incidence of fatal traumatic injury has significantly decreased; the leading causes of nonfatal injury do not correlate with the rank order of fatal injury; intentional injury was the leading cause of injury deaths; and scene fatalities represent a poorly studied group of patients who may benefit from primary prevention and injury control research.

Trauma fatalities: time and location of hospital deaths

BACKGROUND

Analysis of the epidemiology, temporal distribution, and place of traumatic hospital deaths can be a useful tool in identifying areas for research, education, and allocation of resources.

STUDY DESIGN

Trauma registry-based study of all traumatic hospital deaths at a Level I urban trauma center during the period 1993 to 2002. The time and hospital location where deaths occurred were analyzed according to mechanism of injury, age, Glasgow Coma Score, and body areas with severe injury (Abbreviated Injury Scale [AIS] >/= 4). Logistic regression analysis was used to identify risk factors associated with death at various times after admission.

RESULTS

During the study period there were 2,648 hospital trauma deaths. The most common body area with critical injuries (AIS >/= 4) was the head (43%), followed by the chest (28%) and the abdomen (19%). Overall, 37% of victims had no vital signs present on admission. Chest AIS >/= 4, penetrating trauma, and age greater than 60 years were significant risk factors associated with no vital signs on admission. Patients with severe chest trauma (AIS >/= 4) reaching the hospital alive were significantly more likely to die within the first 60 minutes than were patients with severe abdominal or head injuries (17% versus 11% versus 7%). In patients reaching the hospital alive, the time and place of death varied according to mechanism of injury and injured body area. Deaths caused by severe head trauma peaked at 6 to 24 hours, and deaths caused by severe chest or abdominal trauma peaked at 1 to 6 hours after admission.

CONCLUSIONS

The temporal distribution and location of trauma deaths are influenced by the mechanism of injury, age, and the injured body area. These findings may help in focusing research, education, and resource allocation in a more targeted manner to reduce trauma deaths.

A clinical review of bleeding dilemmas in trauma

Trauma is rapidly replacing stroke and cardiovascular disease as a leading cause of death in Western countries such as the United States, and almost a third (30%) of trauma deaths are due to blood loss. Although the new intervention strategies that have been developed and adopted by emergency care staff have reduced this mortality in recent years, bleeding continues to be a major challenge in the management of trauma patients. This paper reviews recent developments and controversies in trauma care, and, in particular, the potential role of procoagulant therapy using recombinant factor VIIa in the prevention of mortality due to bleeding.

Structural design of the dry fibrin sealant dressing and its impact on the hemostatic efficacy of the product

We compared the hemostatic efficacy of a production version of a dry fibrin sealant dressing (DFSD) to a prototype that was previously successful in large animal studies. The results were used to improve manufacturing processes. Grade-V liver injuries were induced in swine and treated with gauze sponges (GAU), the prototype dressings (DFSD-1), or the scaled-up production version dressings (DFSD-2 in experiment 1 and DFSD-3 in experiment 2). Blood loss, hemostasis, resuscitation volume, and 60-min survival were quantified. In experiment 1, the DFSD-1 treatment reduced blood loss (p < 0.01), increased hemostasis at 4 min (p < 0.05), and improved survival (p < 0.05) compared with GAU. The DFSHD-2 decreased blood loss (p < 0.05) but did not increase hemostasis or survival significantly. Based on these results, manufacturing processes were altered, producing DFSD-3. In experiment 2, the DFSD-1 and DFSD-3 were equally effective in reducing blood loss (p < 0.01) and resuscitation volume (p < 0.05) compared with GAU. Hemostasis occurred more frequently in both the DFSD-1 and DFSD-3 groups (p < 0.01) compared with GAU. The structural design of DFSD-2 did not meet the efficacy requirement for release of the product. The subsequent change incorporated in DFSD-3 improved all hemostatic parameters of the dressings equal to those of the prototype product.

Bleeding Manifestations after Early Use of Low-Molecular-Weight Heparins in Blunt Splenic Injuries

Low-molecular-weight heparins (LMWHs) have emerged as an effective method for deep venous thrombosis (DVT) prophylaxis after major trauma. The early use of LMWH in patients with splenic injuries may result in increased rates of blood transfusions and failure of nonoperative management. A retrospective review of the records of all patients ≥18 years old that sustained blunt splenic injuries from April 2000 to July 2002 was performed. Patients were divided in two groups based on whether they received LMWH during the first 48 hours (early group) or not (late group). A total of 188 patients were evaluated. One hundred fourteen patients had their splenic injuries managed nonoperatively and were included in the study. Fifty patients were assigned to the early group and 64 to the late group. There was no statistical difference between groups regarding basic demographic data, initial laboratory results, and severity of their splenic injuries. In the early group, two (4%) patients failed nonoperative management compared with four (6%) patients in the late group ( P = 0.593). The number of patients requiring blood transfusions within the first 5 days after admission was 25 (50.0%) in the early group and 36 (56.2%) in the late group ( P = 0.507). The average number of blood units given per patient within the first 5 days after admission were 3.2 ± 1.5 in the early group and 3.0 ± 1.8 in the late group ( P = 0.782). This study suggests that the early use of LMWH in trauma patients with splenic injuries is not associated with an increased rate of blood transfusion requirements or an increased rate of failure of non-operative management.

Nonintracranial Fatal Firearm Injuries in Children: Implications for Treatment

BACKGROUND

Understanding the injury characteristics of nonintracranial fatal (NIF) gunshot wounds in children treated in a statewide trauma system will help guide effective treatment strategies.

METHODS

This study was a retrospective analysis of children fatally injured with firearms. The review included demographic information, firearm injury characteristics, and outcome. The setting included trauma centers participating in a statewide trauma registry. Patients were all children (age < 18 years) treated in trauma centers for NIF gunshot wounds from January 1988 through December 2000. The main outcome measures were characteristics of fatal firearm injuries in children.

RESULTS

Over the 13-year period, there were 1,954 children with firearm injuries including 368 (18.8%) children with fatal wounds. Of the fatally wounded children, 177 (48.1%) had no intracranial injury. The NIF injury population was 90.4% male, with a mean age of 14.9 years (range, <1-17 years) and an Injury Severity Score of 38.2 (range, 9-75). Over 95% of deaths in this group occurred within 24 hours of admission. Although injuries to the thorax were most common (78.5%), 48.6% of the NIF cohort had injuries to multiple body regions, including 31% with injuries in both the abdomen and thorax. Compared with all children wounded by firearms, NIF firearm injury patients had, on average, more body regions injured (1.6 vs. 1.1, p < 0.001) and a greater total number of injuries (6.0 vs. 3.5, p < 0.001). Patients with an NIF injury were more likely to suffer a major vascular injury (54.8% vs. 13.8%, p < 0.001), lung injury (56.5% vs. 12.9%, p < 0.001), or cardiac injury (44.6% vs. 4.6%, p < 0.001) than all children with a firearm injury.

CONCLUSION

Most children who arrive at trauma centers alive and subsequently die from NIF firearm injuries do so rapidly from major vascular and thoracic injury. Almost half of these children have injuries to multiple body regions, further complicating management. Innovative, aggressive treatment approaches should be sought to improve survival in this extremely injured cohort of children.

Advanced Hemostatic Dressing Development Program: Animal Model Selection Criteria and Results of a Study of Nine Hemostatic Dressings in a Model of Severe Large Venous Hemorrhage and Hepatic Injury in Swine

BACKGROUND

An advanced hemostatic dressing is needed to augment current methods for the control of life-threatening hemorrhage. A systematic approach to the study of dressings is described. We studied the effects of nine hemostatic dressings on blood loss using a model of severe venous hemorrhage and hepatic injury in swine.

METHODS

Swine were treated using one of nine hemostatic dressings. Dressings used the following primary active ingredients: microfibrillar collagen, oxidized cellulose, thrombin, fibrinogen, propyl gallate, aluminum sulfate, and fully acetylated poly-N-acetyl glucosamine. Standardized liver injuries were induced, dressings were applied, and resuscitation was initiated. Blood loss, hemostasis, and 60-minute survival were quantified.

RESULTS

The American Red Cross hemostatic dressing (fibrinogen and thrombin) reduced (p < 0.01) posttreatment blood loss (366 mL; 95% confidence interval, 175-762 mL) and increased (p < 0.05) the percentage of animals in which hemostasis was attained (73%), compared with gauze controls (2,973 mL; 95% confidence interval, 1,414-6,102 mL and 0%, respectively). No other dressing was effective. The number of vessels lacerated was positively related to pretreatment blood loss and negatively related to hemostasis.

CONCLUSION

The hemorrhage model allowed differentiation among topical hemostatic agents for severe hemorrhage. The American Red Cross hemostatic dressing was effective and warrants further development.

The Impact of Pelvic and Lower Extremity Fractures on the Incidence of Lower Extremity Deep Vein Thrombosis in High-Risk Trauma Patients

Lower extremity fractures (LEFx) and pelvic fractures (PFx) are believed to increase the risk of lower extremity deep vein thrombosis (LEDVT). We studied trauma patients at high risk for LEDVT to determine whether an increased incidence of LEDVT was associated with LEFx and/or PFx. From January 1995 through December 1997 4163 trauma patients were admitted to our Level I trauma center. One thousand ninety-three patients at high risk for LEDVT were screened with serial lower extremity venous duplex ultrasound. Their medical records were retrospectively reviewed for demographics, mechanism of injury, and fracture data. The occurrence of LEDVT, pulmonary embolus, and LEDVT prophylaxis and treatment were noted. The incidence of LEDVT in the fracture group (Fx) was compared with that in the nonfracture group (NFx) using chi-square analysis and logistic regression. Statistical significance was set at ≤0.05. Complete data were available for 1059 of 1093 patients. Five hundred sixty-nine (53.73%) patients had PFx and/or LEFx, 151 (14.26%) patients had PFx only, 317 (29.3%) patients had LEFx only, and 101 (9.54%) patients had both PFx and LEFx. Four hundred ninety (46.27%) patients had NFx. In 1059 patients LEDVT was detected in 125 (11.8%). Sixty-three patients in the Fx groups developed LEDVT (50.4%): 19 (15.2%) PFx patients, 15 (12.0%) PFx/LEFx patients, and 29 (23.2%) LEFx patients. Sixty-two (49.6%) NFx patients developed LEDVT. LEDVT incidence was not significantly different between the Fx and NFx groups or among the PFx, LEFx, and PFx/LEFx groups ( P = 0.317). Nine patients developed pulmonary embolism: four NFx patients, two LEFx patients, two PFx patients, and one PFx/LEFx patient. Significant predictors of LEDVT were age and hospital length of stay. Mean age in patients with LEDVT was 47.58 years and in patients without LEDVT it was 40.89 years ( P < 0.001). Mean hospital length of stay in patients with LEDVT was 29.81 days and in patients without LEDVT it was 16.84 days. The power of this study to detect differences representing medium effect sizes was greater than 90 per cent. We conclude that LEFx and/or PFx was not associated with an increased incidence of LEDVT in trauma patients at high risk for LEDVT. Lower extremity venous duplex ultrasound needs to be performed in both Fx and NFx groups to detect LEDVTs.

Fluid resuscitation: the target from an analysis of trauma systems and patient survival

Much can be learned from studying the deaths that occur in trauma systems as they have developed. Understanding these deaths and the potential effect of trauma systems on reducing death has major implications for designing clinical trials in fluid resuscitation. The availability of new, exciting information regarding fluid composition and physiologic effects argues for new, better-designed clinical trials. By agreeing on the form of resuscitation trials in the future, we will increase our ability to see clinically significant differences in outcome as we move from animal data to clinical efficacy.

Seven hundred fifty-three consecutive deaths in a level I trauma center: the argument for injury prevention

BACKGROUND

The past century has seen improvement in trauma care, with a resulting decrease in therapeutically preventable deaths. We hypothesize that further major reduction in injury mortality will be obtained through injury prevention, rather than improvements in therapy.

METHODS

Seven hundred fifty-three deaths in an American College of Surgeons-verified, Level I trauma center were reviewed as they occurred. Deaths were classified as therapeutically not preventable, possibly preventable, or preventable. These charts were also reviewed for factors that might have prevented or lessened the severity of the injury.

RESULTS

Mean age was 43, mean Glasgow Coma Scale score was 5, mean Revised Trauma Score was 4, mean Injury Severity Score was 41, and mean probability of survival was 0.25 (according to TRISS). Forty-six percent underwent cardiopulmonary resuscitation in the field, 52% died within 12 hours, 74% died within 48 hours, and 86% died within 7 days. Primary causes of death included central nervous system injury in 51%, irreversible shock in 21%, multiple injuries (shock plus central nervous system injury) in 9%, multiple organ failure/sepsis and other causes in 3%, and pulmonary embolus in 0.1%. Seven hundred one (93%) were classified as not preventable with a change in therapy, 32 (4.2%) were classified as potentially preventable with a change in therapy, and 20 were classified as preventable with a change in therapy (2.6%). Forty-six percent had cardiopulmonary resuscitation performed before or immediately on arrival to the hospital. Another 23% had vital signs present on arrival, but had a Glasgow Coma Scale score of <or= 4. Of the 546 unintentionally injured patients, 58% had an identifiable factor that contributed to the presence and/or severity of the injury (intoxication, restraint and helmet use), with 28% of patients having a positive blood alcohol level. Of the 206 patients with intentional injuries, 44% were intoxicated at the time of their death. Commensurate with driving-while-intoxicated prevention program(s), the percentage of intoxicated patients significantly ( p= 0.03) decreased from 45% to 34% over the same 7-year period.

CONCLUSION

Dramatically improving therapy (no errors, cure for multiple organ failure, sepsis, and pulmonary embolus) in a modern trauma system would decrease trauma mortality by 13%. In contrast, more than half of all deaths are potentially preventable with preinjury behavioral changes. Injury prevention is critical to reducing deaths in the modern trauma system.

Effect of a chitosan-based hemostatic dressing on blood loss and survival in a model of severe venous hemorrhage and hepatic injury in swine

BACKGROUND

Hemorrhage is a leading cause of death from trauma. An advanced hemostatic dressing could augment available hemostatic methods. We studied the effects of a new chitosan dressing on blood loss, survival, and fluid use after severe hepatic injury in swine.

METHODS

Swine received chitosan dressings or gauze sponges. Standardized, severe liver injuries were induced. After 30 seconds, dressings were applied and resuscitation initiated. Blood loss, hemostasis, resuscitation volume, and 60-minute survival were quantified.

RESULTS

Posttreatment blood loss was reduced ( p< 0.01) in the chitosan group (264 mL; 95% confidence interval [CI], 82-852 mL) compared with the gauze group (2,879 mL; 95% CI, 788-10,513 mL). Fluid use was reduced ( p= 0.03) in the chitosan group (1,793 mL; 95% CI, 749-4,291) compared with the gauze group (6,614 mL; 95% CI, 2,519-17,363 mL). Survival was seven of eight and two of even in the chitosan and gauze groups ( p= 0.04), respectively. Hemostasis was improved in the chitosan group ( p= 0.03).

CONCLUSION

A chitosan dressing reduced hemorrhage and improved survival after severe liver injury in swine. Further studies are warranted.

Factors associated with mortality in patients with penetrating abdominal vascular trauma

OBJECTIVE

Prehospital transport, resuscitation, and operative intervention are all critical to the care of the penetrating trauma victim. We determined which factors most affected mortality in patients with penetrating abdominal vascular injuries.

METHODS

Consecutive patients with penetrating abdominal vascular injuries from an urban Level I trauma center from January 1993 to December 1998 were identified from the trauma registry and their charts reviewed. All patients who died prior to operative intervention were excluded. Data collected included mortality, age, scene time (ST), EMS transport time (TT), time in the emergency department (ED), initial systolic blood pressure in the ED (BP), operating time, intraoperative estimated blood loss (EBL), and worst base deficit in the first 24 h (BD). These variables were compared between nonsurvivors and survivors by univariate ANOVA. Multivariate ANOVA (MANOVA) determined independent effects on mortality.

RESULTS

Forty-six penetrating abdominal vascular injuries were identified in 31 patients, 11 of whom died (38.7%). Examining prehospital parameters, mean ST averaged 16.5 +/- 3.6 min, while TT was 31.8 +/- 7.1 min. For ED parameters, initial BP was 94.8 +/- 6.4 mm Hg and initial heart rate was 109 +/- 7 beats per minute. Mean operative EBL for all patients was 3518 +/- 433 ml. The mean BD for all patients was -12.9 +/- 1.8. Significant differences were noted in the univariate analysis between survivors and nonsurvivors for BD (P < 0.0001), BP (P = 0.0062) and EBL (P = 0.0002). MANOVA revealed that only base deficit (P < 0.0001) had an independent effect on mortality.

CONCLUSIONS

In patients with penetrating abdominal vascular injuries who survive their ED stay, adverse physiologic parameters reflecting the adequacy of resuscitation are more predictive of mortality than identifiable prehospital parameters.

Hepatic dysfunction increases length of stay and risk of death after injury

BACKGROUND

The relative importance of dysfunction or failure of different organ systems to recovery from critical illness is unclear. The purpose of this study was to evaluate the contribution of hepatic dysfunction to outcome after injury.

METHODS

We retrospectively evaluated patients admitted to our trauma center from 1994 to 1998 for the development of hepatic dysfunction, defined as serum bilirubin > or = 2.0 mg/dL. Additional variables on patient demographics, injuries, hospital course, and development of other organ system dysfunction were collected from the trauma registry and hospital records.

RESULTS

Using logistic regression analysis, hepatic dysfunction was significantly associated with increased intensive care unit length of stay (LOS) and death. The added development of hepatic dysfunction significantly increased LOS in patients with no other organ dysfunction, those with renal dysfunction, and those with respiratory dysfunction.

CONCLUSION

Hepatic dysfunction influences recovery after injury independent of the dysfunction of other organ systems. The development of hepatic dysfunction prolongs LOS and increases mortality.

Risk factors for mortality within first 24 hours of head injury

OBJECTIVE

Immediate or instantaneous death following cranial trauma occurs due to unpreventable primary brain insults. However, death occurring within 24 hours of head injury can be averted by timely institution of the therapeutic measures that could prevent secondary brain insults. From the management point of view, this is the most important subset of all head injured patients. Therefore, it is important to study risk factors associated with such deaths.

METHODS

In a retrospective study undertaken at Trauma Center, Safdarjang Hospital, New Delhi, the demographic characteristics, neurological and radiological findings were studied for 100 head injured children admitted in the pediatric surgical ward, who later died after surviving the initial neurosurgical resuscitation. Death occurring within first 24 hours of head injury was defined as "early" death; and "late death", if it occurred thereafter.

RESULTS

Bivariate analysis revealed the severity of head injury GCS<=8 (OR: 3.09; 95% CI: 1.22-7.8), a finding of diffuse brain edema, (OR: 3.73; 95% CI: 0.95-14.74), midline shift (OR: 4.8; 95% CI: 1.03-22.37) on cranial CT scans were found to be statistically associated with early deaths. Child's age or gender, the mode of injury and the presence of extracerebral injuries were not found to be significantly associated. When these variables were simultaneously considered in a multivariate logistic regression model, the diffuse brain edema on head CT scan was found to be both clinically and statistically significant of early death (Adj. OR: 527; 95% CI: 1.23-22.6). However, absence of hemorrhagic contusion was clinically important predictor of an early death (Adj. OR: 6.45; 95% CI: 0.68.-62.5) though not statistically significant

Coagulation management in trauma patients

Hemorrhage after traumatic injury results in coagulopathy which only worsens the situation. This coagulopathy is caused by depletion and dilution of clotting factors and platelets, increased fibrinolytic activity, hypothermia, metabolic changes and anemia. The effect of synthetic colloids in compensating the blood loss further aggravates the situation. Bedside coagulation monitoring permits relevant impairment of the coagulation system to be detected very early and the efficacy of the hemostatic therapy to be controlled directly. Administration of fresh frozen plasma, platelet concentrations, clotting factors and probably antifibrinolytic agents is essential in restoring the impaired coagulation system in trauma patients.

[Strategies diagnosis of polytraumatized adult patients with coma]

OBJECTIVE

To review the diagnostic strategy of management of multiple trauma patient during the first hours.

DATA SOURCES

Extraction from Pubmed database of French and English articles on the management of multiple trauma patient published for ten years.

DATA SELECTION

The collected articles were reviewed and selected according to their quality and originality. The more recent data were selected.

DATA SYNTHESIS

The first hours of management of multiple trauma patients are a particular challenge. The first dilemma is to drive the patient toward an adequate structure. In case of poor haemodynamic tolerance, the patient will be drive in the nearest hospital. When haemodynamic parameters are restored, multiple trauma patient has to be receive in a high level hospital by a trained medical team with an anesthesiologist, intensivist, neurosurgeon, general surgeon and radiologist. The initial assessment may have two priorities: quality and speed. The total body CT scan is actually the answer to these priorities.

Enoxaparin for thromboprophylaxis after major trauma: potential cost implications

OBJECTIVE

To determine the cost-effectiveness of enoxaparin compared with low-dose-heparin (LDH) for thromboprophylaxis after major trauma and to assess the economic significance of major bleeding as a complication of the use of low-molecular-weight heparin (LMWH).

DESIGN

Decision model analysis of the cost and efficacy of enoxaparin at preventing venous thromboembolism (VTE) and the risk and costs of major hemorrhage related to LMWH. The primary outcome was deep vein thromboses (DVTs) averted. Model estimates were based on data from prospective trials of LMWH and other studies of the financial ramifications of DVT and pulmonary embolism.

SETTING AND PATIENTS

Hypothetical cohort of 1,000 critically ill trauma patients requiring thromboprophylaxis.

INTERVENTIONS

In the model, patients were managed with either LMWH or LDH.

MEASUREMENTS AND MAIN RESULTS

The marginal cost-effectiveness of enoxaparin was calculated as the savings resulting from cases of DVT averted less the additional costs of both 1) LMWH and 2) major bleeding. This result is expressed as cost (or savings) per DVT prevented. Sensitivity analysis of the impact of the major clinical inputs on the cost-effectiveness was performed. The base case assumed that the incidence of DVT with LDH was 14.7%, that LMWH resulted in a relative risk reduction of DVT of 50%, but that enoxaparin nearly quadrupled the risk of bleeding. Despite the higher costs of enoxaparin, this tactic yielded a net savings of $391.23 per DVT prevented. For sensitivity analysis, model inputs were adjusted by 25% individually and then simultaneously. This demonstrated the model to be most sensitive to the calculated cost of a DVT. With the efficacy of LMWH reduced by 25% of the base-case estimate, enoxaparin resulted in a cost of $311.77 per DVT avoided. When all variables were skewed against LMWH, total outlays were trivial (approximately $85 per patient in the cohort). Neither the rate of increased bleeding with LMWH nor the costs incurred as a result of bleeding significantly altered the model's financial outcomes.

CONCLUSIONS

Reliance on enoxaparin represents a strategy for the prevention of VTE after trauma that may result in savings. Neither concerns about the higher cost of enoxaprin relative to LDH nor the financial implications of major bleeding should preclude the use of LWMH for thromboprophylaxis in trauma patients. Further studies are warranted to confirm the efficacy of enoxaparin.

Epidemiology of severe brain injuries: a prospective population-based study

BACKGROUND

The aim of this prospective study was to estimate annual incidences of hospitalization for severe traumatic brain injury (TBI) (maximum Abbreviated Injury Score in the head region [HAIS] 4 or 5) in a defined population of 2.8 million.

METHODS

Severe TBI patients were included in the emergency departments in the 19 hospitals of the region. A prospective data form was completed with initial neurologic state, computed tomographic scan lesions, associated injuries, length of unconsciousness, and length of stay in acute care centers. Outcome at the time the patient left acute hospitalization was retrospectively assessed from medical notes.

RESULTS

During the 1-year period (1996), 497 residents fulfilled the inclusion criteria, leading to an annual incidence rate of 17.3 per 100,000 population; 58.1% were HAIS5. Mortality rate was 5.2 per 100,000. Men accounted for 71.4% of cases. Median age was 44 years, with a quarter of patients more than 70 years old. Traffic accidents were the most frequent causes (48.3%), but falls accounted for 41.8% of all patients. Age and severity were different according to the major categories of external causes. In HAIS5 patients, 86.5% were considered as comatose (coma lasting more than 24 hours or leading to immediate death) but only 60.9% had an initial Glasgow Coma Scale score < 9. In the HAIS4 group, 7.2% had an initial Glasgow Coma Scale score < 9. Fatality rates were 30.0% in the whole study group, 7.7% in HAIS4, 12.8% in HAIS5 without coma, and 51.2% in HAIS5 with coma.

CONCLUSION

This study shows a decrease in severe TBI incidence when results are compared with another study conducted 10 years earlier in the same region. This is because of a decrease in traffic accidents. However, this results in an increase in the proportion of falls in elderly patients and an increase in the median age in our patients. This increased age influences the mortality rate.

Late deaths in multiple trauma patients receiving intensive care

We reviewed the cause and timing of death of all the patients who died within hospital following multiple trauma and admission to a multidisciplinary intensive care unit (ICU) that also acts as a tertiary referral centre for neurosurgery. The ICU database identified 101 such patients in a 3-year period and their records were reviewed retrospectively. There were 40 (39%) deaths within 24 h of admission to the ICU, 38 of which resulted from severe brain injury and two from haemorrhagic shock (HS). A further 61 (60%) deaths occurred more than 24 h after the time of admission to ICU (mean 7 days; range 2-49 days), of which 46 (75%) were due to severe brain injury. While these findings do not question the promulgated tri-modal distribution of death following trauma, they are at variance with the view that the third peak of deaths is due mainly to multiple organ failure. When severe head injury accompanies multiple trauma, it is likely to be the major determinant of late mortality. If outcome from major trauma is to be improved, then a greater emphasis needs to be placed on the prevention and optimal management of severe brain injury.

Intravenous rFVIIa administered for hemorrhage control in hypothermic coagulopathic swine with grade V liver injuries

BACKGROUND

Intravenous administration of recombinant activated human clotting factor VII (rFVIIa) has been used successfully to prevent bleeding in hemophilia patients undergoing elective surgery, but not in previously normal trauma patients. This study was conducted to determine whether rFVIIa was a useful adjunct to gauze packing for decreasing blood loss from grade V liver injuries in hypothermic and coagulopathic swine.

METHODS

All animals (n = 10, 35 +/- 2 kg) underwent a 60% isovolemic exchange transfusion with 6% hydroxyethyl starch and were cooled to 33 degrees C core temperature. The swine then received a grade V liver injury and 30 seconds later, either 180 microg/kg rFVIIa, or saline control. All animals were gauze packed 30 seconds after injury and resuscitated 5.5 minutes after injury with lactated Ringer's solution to their preinjury mean arterial pressure. Posttreatment blood loss, mean arterial pressure, resuscitation volume, and clotting studies were monitored for 1 hour. Histology of lung, kidney, and small bowel were obtained to evaluate for the presence of microvascular thrombi.

RESULTS

At the time of injury, core temperature was 33.3 degrees +/- 0.4 degrees C, hemoglobin was 6 +/- 0.7 g/dL, prothrombin time was 19.1 +/- 1.0 seconds, activated partial thromboplastin time was 29.0 +/- 4.8 seconds, fibrinogen was 91 +/- 20 mg/dL, and platelets were 221 +/- 57 x 105/mL, with no differences between groups (p > 0.05). Clotting factor levels confirmed a coagulopathy at the preinjury point. The posttreatment blood loss was less (p < 0.05) in group 1 (527 +/- 323 mL), than in group 2 (976 +/- 573 mL). The resuscitation volume was not different (p > 0.05). One-hour survival in both groups was 100%. Compared with the control group, rFVIIa increased the circulating levels of VIIa and, despite hypothermia, shortened the prothrombin time 5 minutes after injection (p < 0.05). Laboratory evaluation revealed no systemic activation of the clotting cascade. Postmortem evaluation revealed no evidence of large clots in the hepatic veins or inferior vena cava, or microscopic thrombi in lung, kidney, or small intestine.

CONCLUSION

rFVIIa reduced blood loss and restored abnormal coagulation function when used in conjunction with liver packing in hypothermic and coagulopathic swine. No adverse effects were identified.

Vascular trauma at a military level II trauma center(1)

As members of an American College of Surgeons Committee on Trauma-designated level II trauma center, we decided to review our experience with vascular trauma. In addition, we sought to characterize the vascular injuries presented and to compare our outcomes to the general trauma population.A review of all vascular trauma admissions from January 1997 through January 2000 was performed. The William Beaumont Army Medical Center (WBAMC) trauma registry data base was searched for vascular injuries utilizing 3 different search criteria: organ system, operation/procedure, and ICD-9 codes. Injuries were then characterized by age, gender, site of injury, injury severity score (ISS), mechanism, and need for surgery. Mortality rates were computed for both vascular and nonvascular trauma populations. Statistical analysis of the data was determined by Student t test and z score.Between January 1997 and January 2000, there were 1398 patients admitted to the trauma service at WBAMC. Of these, 48 patients (3.4%) had vascular injuries. The mean ISS for all nonvascular traumas was 8.4 +/- 8.9. The mean ISS for those with vascular injuries was 17.9 +/- 12.6 (p < 0.001). Blunt trauma accounted for 90% of all nonvascular admissions. Penetrating trauma accounted for 10% of all nonvascular admissions. In the vascular trauma population, blunt trauma accounted for 56% and penetrating trauma accounted for 39%. Five percent of the vascular injuries identified were iatrogenic. Surgical intervention was required in 85.4% and 44.2% of the vascular and nonvascular trauma populations, respectively. The mortality rate for nonvascular admissions was 4.8% (65/1350). Those with vascular injuries had a mortality rate of 20.8% (10/48). For trauma patients requiring an operation, the mortality rate was 4.5% (27/597). For patients with vascular injuries who required an operation, the mortality rate was 25.7% (9/35) (p = 0.007).Vascular trauma represents a small percentage of all trauma admissions. These patients have a higher ISS on admission and more of them require surgical intervention. The operative and overall mortality rates are higher in patients with vascular injuries than in the general trauma population.

Prehospital trauma care

Concepts regarding uniform reporting of data after trauma and regarding treatment of brain trauma patients at the scene have recently been agreed upon in consensus processes. Endotracheal intubation and alternatives are as controversially discussed as fluid resuscitation and helicopter transport of trauma victims. Long-term outcomes of trauma patients should more frequently be studied using the Quality of Wellbeing Scale.