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

Hydrophobically modified chitosan gauze: a novel topical hemostat

BACKGROUND

Currently, the standard of care for treating severe hemorrhage in a military setting is Combat Gauze (CG). Previous work has shown that hydrophobically modified chitosan (hm-C) has significant hemostatic capability relative to its native chitosan counterpart. This work aims to evaluate gauze coated in hm-C relative to CG as well as ChitoGauze (ChG) in a lethal in vivo hemorrhage model.

METHODS

Twelve Yorkshire swine were randomized to receive either hm-C gauze (n = 4), ChG (n = 4), or CG (n = 4). A standard hemorrhage model was used in which animals underwent a splenectomy before a 6-mm punch arterial puncture of the femoral artery. Thirty seconds of free bleeding was allowed before dressings were applied and compressed for 3 min. Baseline mean arterial pressure was preserved via fluid resuscitation. Experiments were conducted for 3 h after which any surviving animal was euthanized.

RESULTS

hm-C gauze was found to be at least equivalent to both CG and ChG in terms of overall survival (100% versus 75%), number of dressing used (6 versus 7), and duration of hemostasis (3 h versus 2.25 h). Total post-treatment blood loss was lower in the hm-C gauze treatment group (4.7 mL/kg) when compared to CG (13.4 mL/kg) and ChG (12.1 mL/kg) groups.

CONCLUSIONS

hm-C gauze outperformed both CG and ChG in a lethal hemorrhage model but without statistical significance for key endpoints. Future comparison of hm-C gauze to CG and ChG will be performed on a hypothermic, coagulopathic model that should allow for outcome significance to be differentiated under small treatment groups.

Mortality Patterns in Patients with Multiple Trauma: A Systematic Review of Autopsy Studies

PURPOSE

A high percentage (50%-60%) of trauma patients die due to their injuries prior to arrival at the hospital. Studies on preclinical mortality including post-mortem examinations are rare. In this review, we summarized the literature focusing on clinical and preclinical mortality and studies included post-mortem examinations.

METHODS

A literature search was conducted using PubMed/Medline database for relevant medical literature in English or German language published within the last four decades (1980-2015). The following MeSH search terms were used in different combinations: "multiple trauma", "epidemiology", "mortality ", "cause of death", and "autopsy". References from available studies were searched as well.

RESULTS

Marked differences in demographic parameters and injury severity between studies were identified. Moreover, the incidence of penetrating injuries has shown a wide range (between 4% and 38%). Both unimodal and bimodal concepts of trauma mortality have been favored. Studies have shown a wide variation in time intervals used to analyze the distribution of death. Thus, it is difficult to say which distribution is correct.

CONCLUSIONS

We have identified variable results indicating bimodal or unimodal death distribution. Further more stundardized studies in this field are needed. We would like to encourage investigators to choose the inclusion criteria more critically and to consider factors affecting the pattern of mortality.

A Ten year review of alcohol use and major trauma in a Canadian province: still a major problem

Background

Alcohol plays a significant role in major traumatic injuries. While the role of alcohol in motor vehicle trauma (MVT) is well described, its role and approaches to prevention in other injury mechanisms is less defined.

Methods

A 10 year retrospective examination of Alberta Trauma Registry (ATR) data was conducted on all major trauma patients (age ≥ 9 and ISS ≥ 12) from 2001–2010. The role and prevalence of alcohol is examined.

Results

Of 22,457 patients included in our study, only 60 %(n = 13,552) were screened for alcohol use. Of those screened, 38 %(n = 5,170) tested positive for alcohol with a mean blood alcohol concentration (BAC) of 39.4 ± 21.1 mmol/L. Of the positive screening tests, 82.3 % had BAC levels greater than the common legal driving limit of 17.4 mmol/L (0.08 %). Testing positive was associated with male gender (p < 0.001) and younger age (p < 0.001). The rate of positive alcohol use in major trauma increased from 20.3 % in 2001 to 24.3 % in 2010, corresponding with a screening rate increase from 51.3 % to 61.2 % over the same period. Railway incidents have the highest rate of alcohol involvement (65 %), followed by undetermined-if-accidental/self-inflicted (53.5 %) and assault (49 %); motor vehicle traffic (MVT) incidents had a frequency of 25.4 %.

Conclusions

The prevalence of alcohol use in major trauma appears to be increasing in Alberta but the true extent is still underappreciated. Furthermore, the role of alcohol in non-MVT injuries is significant and deserves further attention. The vast majority of patients involved in alcohol-related trauma are legally intoxicated. Alcohol use continues to be a substantial contributor to major trauma in Alberta, and represents an important opportunity to reduce preventable injuries.

Activation of Massive Transfusion for Elderly Trauma Patients

Massive transfusion protocol (MTP) is used to resuscitate patients in hemorrhagic shock. Our goal was to review MTP use in the elderly. All trauma patients who required activation of MTP at an urban Level I trauma center from January 1, 2011 to December 31, 2013 were reviewed retrospectively. Elderly was defined as age ≥ 60 years. Sixty-six patients had MTP activated: 52 non-elderly (NE) and 14 elderly (E). There were no statistically significant differences between the two cohorts for gender, injury severity score, head abbreviated injury scale, emergency department Glasgow Coma Scale, initial hematocrit, intensive care unit length of stay, or hospital length of stay. Mean age for NE was 35 years and 73 years for E ( P < 0.01). Less than half (43%) of E patients with activation of MTP received 10 or more units of blood products compared with 69 per cent of the NE ( P = 0.07). Mortality rates were similar in the NE and the E (53% vs 50%, P = 0.80). After multivariate analysis with Glasgow Coma Scale, injury severity score, and blunt versus penetrating trauma, elderly age was not a predictor of mortality after MTP ( P = 0.35). When MTP is activated, survival to discharge in elderly trauma patients is comparable to younger patients.

A controlled resuscitation strategy is feasible and safe in hypotensive trauma patients: results of a prospective randomized pilot trial

BACKGROUND

Optimal resuscitation of hypotensive trauma patients has not been defined. This trial was performed to assess the feasibility and safety of controlled resuscitation (CR) versus standard resuscitation (SR) in hypotensive trauma patients.

METHODS

Patients were enrolled and randomized in the out-of-hospital setting. Nineteen emergency medical services (EMS) systems in the Resuscitation Outcome Consortium participated. Eligible patients had an out-of-hospital systolic blood pressure (SBP) of 90 mm Hg or lower. CR patients received 250 mL of fluid if they had no radial pulse or an SBP lower than 70 mm Hg and additional 250-mL boluses to maintain a radial pulse or an SBP of 70 mm Hg or greater. The SR group patients received 2 L initially and additional fluid as needed to maintain an SBP of 110 mm Hg or greater. The crystalloid protocol was maintained until hemorrhage control or 2 hours after hospital arrival.

RESULTS

A total of 192 patients were randomized (97 CR and 95 SR). The CR and SR groups were similar at baseline. The mean (SD) crystalloid volume administered during the study period was 1.0 L (1.5) in the CR group and 2.0 L (1.4) in the SR group, a difference of 1.0 L (95% confidence interval [CI], 0.6-1.4). Intensive care unit-free days, ventilator-free days, renal injury, and renal failure did not differ between the groups. At 24 hours after admission, there were 5 deaths (5%) in the CR group and 14 (15%) in the SR group (adjusted odds ratio, 0.39; 95% CI, 0.12-1.26). Among patients with blunt trauma, 24-hour mortality was 3% (CR) and 18% (SR) with an adjusted odds ratio of 0.17 (0.03-0.92). There was no difference among patients with penetrating trauma (9% vs. 9%; adjusted odds ratio, 1.93; 95% CI, 0.19-19.17).

CONCLUSION

CR is achievable in out-of-hospital and hospital settings and may offer an early survival advantage in blunt trauma. A large-scale, Phase III trial to examine its effects on survival and other clinical outcomes is warranted.

LEVEL OF EVIDENCE

Therapeutic study, level I.

Sprayable Foams Based on an Amphiphilic Biopolymer for Control of Hemorrhage Without Compression

Hemorrhage (severe blood loss) from traumatic injury is a leading cause of death for soldiers in combat and for young civilians. In some cases, hemorrhage can be stopped by applying compression of a tourniquet or bandage at the injury site. However, the majority of hemorrhages that prove fatal are "non-compressible", such as those due to an internal injury in the truncal region. Currently, there is no effective way to treat such injuries. In this initial study, we demonstrate that a sprayable polymer-based foam can be effective at treating bleeding from soft tissue without the need for compression. When the foam is sprayed into an open cavity created by injury, it expands and forms a self-supporting barrier that counteracts the expulsion of blood from the cavity. The active material in this foam is the amphiphilic biopolymer, hydrophobically modified chitosan (hmC), which physically connects blood cells into clusters via hydrophobic interactions (the hemostatic mechanism of hmC is thus distinct from the natural clotting cascade, and it works even with heparinized or citrated blood). The amphiphilic nature of hmC also allows it to serve as a stabilizer for the bubbles in the foam. We tested the hmC-based hemostatic foam for its ability to arrest bleeding from an injury to the liver in pigs. Hemostasis was achieved within minutes after application of the hmC foams (without the need for external compression). The total blood loss was 90% lower with the hmC foam relative to controls.

Angiographic embolization for major trauma in a low-middle income healthcare setting--A retrospective review

INTRODUCTION

Interventional radiology (IR) provides a range of adjunctive techniques to assist with hemorrhage control after trauma that can be employed pre- or post-operatively. The role of IR in lower-middle income countries (LMICs) remains unexplored. This study describes the use of adjunctive angioembolization (AE) in severely injured patients following its recent implementation at an urban trauma center in a LMIC.

METHODS

Adult patients (≥ 16 years) requiring AE from 2011 to 2013 at a single trauma-care facility were included. Data was collected on demographic parameters, transfer status, injury severity score (ISS), emergency resuscitation characteristics, AE and operative characteristics, complications, and in-hospital mortality. Descriptive analyses were performed.

RESULTS

Thirty six patients underwent AE for trauma-related hemorrhagic complications and were included in the study. Average age was 31.5 (± 11.3) years with a male preponderance (91.7%). Penetrating trauma (61.1%) was the most common type of injury. The primary mechanism of injury was gunshot (58.3%). The median ISS was 24 (IQR: 20-29). Pre-operative AE was performed in 23 (63.9%) patients and these patients had a lower median ISS (22) than those who underwent post-operative AE (p = 0.015). Hepatic (55.6%) and pelvic (33.3%) trauma more commonly required radiological intervention. Bleeding from the right hepatic (n = 14), and the right internal iliac (n = 6) arteries and/or their branches, were more often embolized. Microcoils were the preferred AE agents (61.1%). Median length of hospital stay was 7.5 (IQR: 3-14) days. Eight (22.2%) patients did not survive.

CONCLUSION

With the availability of multi-detector computed tomography and a dedicated interventional radiology suite, implementation of AE for the care of trauma patients in LMIC settings is possible.

Detailed description of all deaths in both the shock and traumatic brain injury hypertonic saline trials of the Resuscitation Outcomes Consortium

OBJECTIVE

To identify causes and timing of mortality in trauma patients to determine targets for future studies.

BACKGROUND

In trials conducted by the Resuscitation Outcomes Consortium in patients with traumatic hypovolemic shock (shock) or traumatic brain injury (TBI), hypertonic saline failed to improve survival. Selecting appropriate candidates is challenging.

METHODS

Retrospective review of patients enrolled in multicenter, randomized trials performed from 2006 to 2009. Inclusion criteria were as follows: injured patients, age 15 years or more with hypovolemic shock [systolic blood pressure (SBP) ≤ 70 mm Hg or SBP 71-90 mm Hg with heart rate ≥ 108) or severe TBI [Glasgow Coma Score (GCS) ≤ 8]. Initial fluid administered was 250 mL of either 7.5% saline with 6% dextran 70, 7.5% saline or 0.9% saline.

RESULTS

A total of 2061 subjects were enrolled (809 shock, 1252 TBI) and 571 (27.7%) died. Survivors were younger than nonsurvivors [30 (interquartile range 23) vs 42 (34)] and had a higher GCS, though similar hemodynamics. Most deaths occurred despite ongoing resuscitation. Forty-six percent of deaths in the TBI cohort were within 24 hours, compared with 82% in the shock cohort and 72% in the cohort with both shock and TBI. Median time to death was 29 hours in the TBI cohort, 2 hours in the shock cohort, and 4 hours in patients with both. Sepsis and multiple organ dysfunction accounted for 2% of deaths.

CONCLUSIONS

Most deaths from trauma with shock or TBI occur within 24 hours from hypovolemic shock or TBI. Novel resuscitation strategies should focus on early deaths, though prevention may have a greater impact.

Traumatic intra-abdominal hemorrhage control: has current technology tipped the balance toward a role for prehospital intervention?

BACKGROUND

The identification and control of traumatic hemorrhage from the torso remains a major challenge and carries a significant mortality despite the reduction of transfer times. This review examines the current technologies that are available for abdominal hemorrhage control within the prehospital setting and evaluates their effectiveness.

METHODS

A systematic search of online databases was undertaken. Where appropriate, evidence was highlighted using the Oxford levels of clinical evidence. The primary outcome assessed was mortality, and secondary outcomes included blood loss and complications associated with each technique.

RESULTS

Of 89 studies, 34 met the inclusion criteria, of which 29 were preclinical in vivo trials and 5 were clinical. Techniques were subdivided into mechanical compression, endovascular control, and energy-based hemostatic devices. Gas insufflation and manual pressure techniques had no associated mortalities. There was one mortality with high intensity focused ultrasound. The intra-abdominal infiltration of foam treatment had 64% and the resuscitative endovascular balloon occlusion of the aorta had 74% mortality risk reduction. In the majority of cases, morbidity and blood loss associated with each interventional procedure were less than their respective controls.

CONCLUSION

Mortality from traumatic intra-abdominal hemorrhage could be reduced through early intervention at the scene by emerging technology. Manual pressure or the resuscitative endovascular balloon occlusion of the aorta techniques have demonstrated clinical effectiveness for the control of major vessel bleeding, although complications need to be carefully considered before advocating clinical use. At present, fast transfer to the trauma center remains paramount.

LEVEL OF EVIDENCE

Systematic review, level IV.

Outcomes in Traumatic Brain Injury for Patients Presenting on Antiplatelet Therapy

An increasing number of patients are presenting to trauma units with head injuries on antiplatelet therapy (APT). The influence of APTon these patients is poorly defined. This study examines the outcomes of patients on APT presenting to the hospital with blunt head trauma (BHT). Registries of two Level I trauma centers were reviewed for patients older than 40 years of age from January 2008 to December 2011 with BHT. Patients on APT were compared with control subjects. Primary outcome measures were in-hospital mortality, intracranial hemorrhage (ICH), and need for neurosurgical intervention (NI). Hospital length of stay (LOS) was a secondary outcome measure. Multivariate analysis was used and adjusted models included antiplatelet status, age, Injury Severity Score (ISS), and Glasgow coma scale (GCS). Patients meeting inclusion criteria and having complete data (n = 1547) were included in the analysis; 422 (27%) patients were taking APT. Rates of ICH, NI, and in-hospital mortality of patients with BHT in our study were 45.4, 3.1, and 5.8 per cent, respectively. Controlling for age, ISS, and GCS, there was no significant difference in ICH (odds ratio [OR], 0.84; 95% confidence interval [CI], 0.61 to 1.16), NI (OR, 1.26; 95% CI, 0.60 to 2.67), or mortality (OR, 1.79; 95% CI, 0.89 to 3.59) associated with APT. Subgroup analysis revealed that patients with ISS 20 or greater on APT had increased in-hospital mortality (OR, 2.34; 95% CI, 1.03 to 5.31). LOS greater than 14 days was more likely in the APT group than those in the non-APT group (OR, 1.85; 95% CI, 1.09 to 3.12). The effects of antiplatelet therapy in patients with BHT aged 40 years and older showed no difference in ICH, NI, and in-hospital mortality.

Preventable mortality in geriatric hip fracture inpatients

There is a high rate of mortality in elderly patients who sustain a fracture of the hip. We aimed to determine the rate of preventable mortality and errors during the management of these patients. A 12 month prospective study was performed on patients aged > 65 years who had sustained a fracture of the hip. This was conducted at a Level 1 Trauma Centre with no orthogeriatric service. A multidisciplinary review of the medical records by four specialists was performed to analyse errors of management and elements of preventable mortality. During 2011, there were 437 patients aged > 65 years admitted with a fracture of the hip (85 years (66 to 99)) and 20 died while in hospital (86.3 years (67 to 96)). A total of 152 errors were identified in the 80 individual reviews of the 20 deaths. A total of 99 errors (65%) were thought to have at least a moderate effect on death; 45 reviews considering death (57%) were thought to have potentially been preventable. Agreement between the panel of reviewers on the preventability of death was fair. A larger-scale assessment of preventable mortality in elderly patients who sustain a fracture of the hip is required. Multidisciplinary review panels could be considered as part of the quality assurance process in the management of these patients.

Cite this article: Bone Joint J 2014;96-B:1178–84.

Management of polytrauma patients in emergency department: An experience of a tertiary care health institution of northern India

BACKGROUND

In a tertiary care institute of northern India, the emergency department receives an average of 6-7 patients with poly trauma every day. Of these patients, some come directly and many are referred from other hospitals from the region. Various problems are faced in the management of patients with poly trauma. This study aimed to elicit various complaints, suggestions and possible solutions in the management of patients with poly trauma.

METHODS

A retrospective cross sectional study was done on 210 patients in the emergency OPD for a period of 2 months. All the records of the patients with poly trauma were studied and the problems during their management were measured against 6 predetermined steps (step I to step VI).

RESULTS

In the younger generation, males were predominantly the primary victims of poly trauma injury, and road traffic accident was the major etiological factor. Injuries involving more than 2 specialties induced many problems during the management of patients with poly trauma. Of 210 patients we studied, 32 patients had problems at various steps and maximum problems in step III, i.e. co-ordination between various specialties in the management of patients with poly trauma.

CONCLUSION

A proper poly trauma management team and a well defined standard operative procedure are the keys to effective management of patients with poly trauma by minimizing the problems encountered.

Traumatic brain injury is not associated with coagulopathy out of proportion to injury in other body regions

BACKGROUND

Coagulopathy following trauma is associated with poor outcomes. Traumatic brain injury has been associated with coagulopathy out of proportion to other body regions. We hypothesized that injury severity and shock determine coagulopathy independent of body region injured.

METHODS

We performed a prospective, multicenter observational study at three Level 1 trauma centers. Conventional coagulation tests (CCTs) and rapid thrombelastography (r-TEG) were used. Admission vital signs, base deficit (BD), CCTs, and r-TEG data were collected. The Abbreviated Injury Scale (AIS) score and Injury Severity Score (ISS) were obtained. Severe injury was defined as AIS score greater than or equal to 3 for each body region. Patients were grouped according to their dominant AIS region of injury. Dominant region of injury was defined as the single region with the highest AIS score. Patients with two or more regions with the same greatest AIS score and patients without a region with an AIS score greater than or equal to 3 were excluded. Coagulation parameters were compared between the dominant AIS region. Significant hypoperfusion was defined as BD greater than or equal to 6.

RESULTS

Of the 795 patients enrolled, 462 met criteria for grouping by dominant AIS region. Patients were predominantly white (59%), were male (75%), experienced blunt trauma (71%), and had a median ISS of 25 (interquartile range, 14-29). Patients with BD greater than or equal to 6 (n = 110) were hypocoagulable by CCT and r-TEG compared with patients with BD less than 6 (n = 223). Patients grouped by dominant AIS region showed no significant differences for any r-TEG or CCT parameter. Patients with BD greater than or equal to 6 demonstrated no difference in any r-TEG or CCT parameter between dominant AIS regions.

CONCLUSION

Coagulopathy results from a combination of tissue injury and shock independent of the dominant region of injury. With the use of AIS as a measure of injury severity, traumatic brain injury was not independently associated with more profound coagulopathy.

LEVEL OF EVIDENCE

Epidemiologic study, level III.

Acute coagulopathy in children with multiple trauma: a retrospective study

BACKGROUND

Acute coagulopathy associated with trauma has been recognized for decades and is a constituent of the "triad of death" together with hypothermia and acidosis.

STUDY OBJECTIVE

The aim of this study was to determine to what extent coagulopathy is already established upon emergency department (ED) admission and the association with the severity of injury, impaired outcome, and mortality.

METHODS

Ninety-one injured children were admitted to the ED in our hospital. Pediatric Trauma Score (PTS), Injury Severity Score (ISS), and Glasgow Coma Scale (GCS) score were used to estimate injury severity, and organ function was assessed by the Sequential Organ Failure Assessment (SOFA) score.

RESULTS

Coagulopathy upon pediatric intensive care unit admission was present in 33 children (39.3%): 21 males and 12 females. PTS ranged from 1 to 12 (mean 8.2) in 51 children without coagulopathy and from -1 to +11 (mean 6.8) in 33 children with coagulopathy (p = 0.087). ISS and GCS ranged from 4 to 57 (mean 28) and from 3 to 11 (mean 7.3), respectively, in the coagulopathy group, whereas in the group without coagulopathy, ISS score ranged from 4 to 41 (mean 20.5; p = 0.08) and GCS from 8 to 15 (mean 12.8; p = 0.01). SOFA ranged from 0 to 10 (mean 3.4) in children without coagulopathy and from 0 to 15 (mean 5.4) in the coagulopathy group (p = 0.002). Among 33 children with coagulopathy, 7 did not survive (21%), all with parenchymal brain damage, whereas all trauma patients without coagulopathy survived (p < 0.001).

CONCLUSION

Acute coagulopathy is present on admission to the ED and is associated with injury severity and significantly higher mortality.

Assessment of traumatic deaths in a level one trauma center in Ankara, Turkey

Trauma management shows significant progress in last decades. Determining the time and place of deaths indicate where to focus to improve our knowledge about trauma. We conducted this retrospective study from data of trauma victims who were brought to a major tertiary hospital which is a level one trauma center in Ankara, Turkey, and died even if during transport or in the hospital between 1 March 2010 and 1 March 2013. The patients' demographic characteristics, trauma mechanisms, time frames and causes of deaths determined by physicians were recorded. Traumas were grouped as "high energy trauma" (HET) and "low energy trauma" (LET). Falls from ground level were defined as LET. 209 traumatic deaths due to trauma or trauma-related conditions were found in the study period. 161 of 209 (78 %) patients suffered from HET. Motor vehicle collisions (MVC) (56 %) were the most common mechanism of trauma followed by burns (16 %), falls (11 %), gunshots (9 %) and stabs (6 %) in this group and traumatic brain injuries (TBI) (41 %) were the most common cause of death followed by circulatory collapse (22 %) and multi-organ failure (20 %). 36 % of deaths occurred before arrival at hospital, 25 % in the first 24 h of admission, 18 % between 2nd and 7th day and 21 % after first week. Trimodal distribution of traumatic deaths was not valid for all types of injuries and the most important factor to decrease traumatic deaths is still prevention. Also we have to keep on searching to improve our knowledge about trauma management.

Role of polymeric biomaterials as wound healing agents

In uncontrolled hemorrhage, the main cause of death on the battlefield and in accidents, half of the deaths are caused by severe blood loss. Polymeric biomaterials have great potential in the control of severe hemorrhage from trauma, which is the second leading cause of death in the civilian community following central nervous system injuries. The intent of this article is to provide a review on currently available biopolymers used as wound dressing agents and to describe their best use as it relates to the condition and type of the wound (acute, chronic, superficial, and full thickness) and the phases of the wound healing process. These biopolymers are beneficial in tissue engineering as scaffolds, hydrogels, and films. Different types of wound dressings based on biopolymers are available in the market, with various physical, chemical, and biological properties. The use of biopolymers as a hemostatic agent depends on its biocompatibility, biodegradability, nonimmunogenicity, and optimal mechanical property. This review summarizes different biopolymers, their physiological characters, and their use as wound healing agents along with biomedical applications.

Current concepts, which effect outcome following major hemorrhage

There are a multitude of factors, which effect outcome following major trauma. The recent conflict in the middle-east has advanced our knowledge and developed clinical practice, here within the UK. This article reviews the current and emerging concepts, which effect the outcome of patients sustaining major hemorrage in trauma.

Hydrophobically-modified chitosan foam: description and hemostatic efficacy

BACKGROUND

Trauma represents a significant public health burden, and hemorrhage alone is responsible for 40% of deaths within the first 24 h after injury. Noncompressible hemorrhage accounts for the majority of hemorrhage-related deaths. Thus, materials which can arrest bleeding rapidly are necessary for improved clinical outcomes. This preliminary study evaluated several self-expanding hydrophobically modified chitosan (HM-CS) foams to determine their efficacy on a noncompressible severe liver injury under resuscitation.

METHODS

Six HM-CS foam formulations (HM-CS1, HM-CS2, HM-CS3, HM-CS4, HM-CS5, and HM-CS6) of different graft types and densities were synthesized, characterized, and packaged into spray canisters using dimethyl ether as the propellant. Expansion profiles of the foams were evaluated in bench testing. Foams were then evaluated in vitro, interaction with blood cells was determined via microscopy, and cytotoxicity was assessed via live-dead cell assay on MCF7 breast cancer cells. For in vivo evaluation, rats underwent a 14 ± 3% hepatectomy. The animals were treated with either: (1) an HM-CS foam formulation, (2) CS foam, and (3) no treatment (NT). All animals were resuscitated with lactated Ringer solution. Survival, total blood loss, mean arterial pressures (MAP), and resuscitation volume were recorded for 60 min.

RESULTS

Microscopy showed blood cells immobilizing into colonies within tight groups of adjacent foam bubbles. HM-CS foam did not display any toxic effects in vitro on MCF7 cells over a 72 h period studied. Application of HM-CS foam after hepatectomy decreased total blood loss (29.3 ± 7.8 mL/kg in HM-CS5 group versus 90.9 ± 20.3 mL/kg in the control group; P <0.001) and improved survival from 0% in controls to 100% in the HM-CS5 group (P <0.001).

CONCLUSIONS

In this model of severe liver injury, spraying HM-CS foams directly on the injured liver surface decreased blood loss and increased survival. HM-CS formulations with the highest levels of hydrophobic modification (HM-CS4 and HM-CS5) resulted in the lowest total blood loss and highest survival rates. This pilot study suggests HM-CS foam may be useful as a hemostatic adjunct or solitary hemostatic intervention.

Ethanol, Trauma, and the Brain

Alcohol intoxication plays a significant and causal role in various fatal injuries. In comparison to sober individuals, intoxicated people have a greater generic risk for being involved in hazardous activities that may result in fatal injuries. However, it is not clear whether the biological effects of acute alcohol intoxication result in worse injuries than those sustained by sober individuals who are injured by identical mechanisms. Alcohol intoxication has a neuroprotective effect in experimental animal models of traumatic brain injury (TBI) but the evidence for a similar effect in humans is controversial. Earlier studies found such a protective effect, but more recent large epidemiological studies have not confirmed this finding; some studies also suggest a dose-related protective or exacerbating effect of alcohol intoxication on TBI. There are two apparent alcohol-associated syndromes in which an otherwise survivable blunt force impact to the head of an intoxicated individual is fatal at the scene. The first is a fatal cardiorespiratory arrest (the so-called alcohol concussion syndrome or “commotio medullaris”); the second is “traumatic basilar subarachnoid hemorrhage” (secondary to tears in the cerebral arteries, particularly the intracranial and extracranial vertebral arteries).

Early trauma induced coagulopathy (ETIC): prevalence across the injury spectrum

INTRODUCTION

Newer studies have hypothesised about a coagulopathy that occurs early after trauma, early trauma induced coagulopathy, ETIC, and is defined by an elevated admission prothrombin time (PT). Also, referred to by some authors as acute traumatic coagulopathy, it has been most often studied in cohorts of severely injured or hypotensive patients. However, we wanted to prospectively investigate ETIC in a large all-comers cohort to confirm its prevalence across the entire spectrum of injury, to evaluate its risk pattern and to determine a possible relationship to reduced survival.

METHODS

We conducted a prospective cohort study at a Level I trauma centre from July 15, 2008 to November 15, 2009. Demographics, injury mechanism, time from injury and to hospital arrival, fluid and blood administration and vital signs were collected at hospital arrival and to the time of first blood sample collection for all patients admitted for 24h or longer. Our primary outcome was the incidence of mortality by the 28th hospital day, referred to as 28 day in-hospital mortality.

RESULTS

701 patients were included in the final study cohort. There was 75.3% male, 25.7% penetrating, with a mean age of 39 years. The overall mortality was 7.3%. ETIC occurred in 114 patients (16.3%) and was found to be independently associated with death (odds of death (per 0.10s increase in PT): 1.10, p=0.001). ETIC patients, as a group, were more severely injured, had more hypotension and head injury and used more crystalloid and blood products than non-ETIC patients. However, even mildly injured patients, who had an ISS<16, normal RTS score, and no fluid resuscitation, had an ETIC prevalence of 11.7% (11/94).

CONCLUSIONS

ETIC is an early, primary post-injury coagulopathy that occurs in 16.3% of admitted trauma patients. It is associated with an increase in mortality, even when controlling for crystalloids, vital signs, injury severity and head injury. It can also be found in approximately 11% of mildly injured patients (patients without physiological derangement or blood product administration). Therefore, further elucidation of ETIC is strategic to impacting trauma patient outcome.

The use of higher platelet: RBC transfusion ratio in the acute phase of trauma resuscitation: a systematic review

OBJECTIVE

With the recognition of early coagulopathy, trauma resuscitation has shifted toward liberal platelet transfusions. The overall benefit of this strategy remains controversial. Our objective was to compare the effects of a liberal use of platelet (higher platelet:RBC ratios) with a conservative approach (lower ratios) in trauma resuscitation.

DATA SOURCES

We systematically searched Medline, Embase, Web of Science, Biosis, Cochrane Central, and Scopus.

STUDY SELECTION

Two independent reviewers selected randomized controlled trials and observational studies comparing two or more platelet:RBC ratios in trauma resuscitation. We excluded studies investigating the use of whole blood or hemostatic products.

DATA EXTRACTION

Two independent reviewers extracted data and assessed the risk of bias. Primary outcomes were early (in ICU or within 30 d) and late (in hospital or after 30 d) mortality. Secondary outcomes were multiple organ failure, lung injury, and sepsis.

DATA SYNTHESIS

From 6,123 citations, no randomized controlled trials were identified. We included seven observational studies (4,230 patients) addressing confounders through multivariable regression or propensity scores. Heterogeneity of studies precluded meta-analysis. Among the five studies including exclusively patients requiring massive transfusions, four observed a lower mortality with higher ratios. Two studies considering nonmassively bleeding patients observed no benefit of using higher ratios. Two studies evaluated the implementation of a massive transfusion protocol; only one study observed a decrease in mortality with higher ratios. Of the two studies at low risk of survival bias, one study observed a survival benefit. Three studies assessed secondary outcomes. One study observed an increase in multiple organ failure with higher ratios, whereas no study demonstrated an increased risk in lung injury or sepsis.

CONCLUSIONS

There is insufficient evidence to strongly support the use of a precise platelet:RBC ratio for trauma resuscitation, especially in nonmassively bleeding patients. Randomized controlled trials evaluating both the safety and efficacy of liberal platelet transfusions are warranted.

A method for linking motor vehicle victim and collision data collected by multiple county agencies

OBJECTIVE

This study assessed roadside and bedside factors associated with early mortality following motor vehicle trauma.

METHODS

This retrospective cohort study evaluated motor vehicle crashes in Orange County Florida in 2009 that became medical examiner cases. Data from the Department of Highway Safety and Motor Vehicles (DHSMV), emergency medical services (EMS), a level I trauma center, and the medical examiner were integrated for the analysis. The primary outcome measure was early death, defined by death within 48 hours of a motor vehicle trauma. Both traditional and nontraditional predictors of early mortality were assessed.

RESULTS

The most significant factors associated with early mortality were as follows: (1) From autopsy: hemothorax (odds ratio [OR] = 8.26, 95% confidence interval [CI]: 1.83-37.3) and liver injury (OR = 4.26, 95% CI: 1.70-15.6); (2) from hospital data: systolic blood pressure (OR = 0.98, 95% CI: 0.96-0.99) and having cardiopulmonary resuscitation (CPR) performed in the emergency department (OR = 13.4, 95% CI: 1.51-118.72); and (3) from DHSMV: involvement of drugs and/or alcohol (OR = 4.27, 95% CI: 1.33-13.6), total fatalities (OR = 6.07, 95% CI: 1.57-23.5), speed of vehicle (OR = 1.06, 95% CI: 1.02-1.09), and number of lanes at the crash scene (OR = 1.58, 95% CI: 1.13-2.20).

CONCLUSION

These results were made possible by integrating 4 distinct data sources. As future research in traffic-related injury moves toward prevention, it will be critical to evaluate new preventative strategies quickly and effectively. A unique number that is both patient and event specific that could be incorporated into each of these databases would make such integration seamless. Successful methods for linking data collected by the multiple agencies involved in motor vehicle collisions will ultimately provide invaluable information for medical personnel, researchers, engineers, planners, and policy makers at the local, state, and national levels to identify safety priorities to reduce crash-related injuries and fatalities.

Changes in the outcomes of severe trauma patients from 15-year experience in a Western European trauma ICU of Emilia Romagna region (1996-2010). A population cross-sectional survey study

BACKGROUND

Our experience in trauma center management increased over time and improved with development of better logistics, optimization of structural and technical resources. In addition recent Government policy in safety regulations for road traffic accident (RTA) prevention, such compulsory helmet use (2000) and seatbelt restraint (2003) were issued with aim of decreasing mortality rate for trauma.

INTRODUCTION

The evaluation of their influence on mortality during the last 15 years can lead to further improvements.

METHODS

In our level I trauma center, 60,247 trauma admissions have been recorded between 1996 and 2010, with 2183 deaths (overall mortality 3.6 %). A total of 2,935 trauma patients with ISS >16 have been admitted to Trauma ICU and recorded in a prospectively collected database (1996-2010). Blunt trauma occurred in 97.1 % of the cases, whilst only 2.5 % were penetrating. A retrospective review of the outcomes was carried out, including mortality, cause of death, morbidity and length of stay (LOS) in the intensive care unit (ICU), with stratification of the outcome changes through the years. Age, sex, mechanism, glasgow coma scale (GCS), systolic blood pressure (SBP), respiratory rate (RR), revised trauma score (RTS), injury severity score (ISS), pH, base excess (BE), as well as therapeutic interventions (i.e., angioembolization and number of blood units transfused in the first 24 h), were included in univariate and multivariate analyses by logistic regression of mortality predictive value.

RESULTS

Overall mortality through the whole period was 17.2 %, and major respiratory morbidity in the ICU was 23.3 %. A significant increase of trauma admissions has been observed (before and after 2001, p < 0.01). Mean GCS (10.2) increased during the period (test trend p < 0.05). Mean age, ISS (24.83) and mechanism did not change significantly, whereas mortality rate decreased showing two marked drops, from 25.8 % in 1996, to 18.3 % in 2000 and again down to 10.3 % in 2004 (test trend p < 0.01). Traumatic brain injury (TBI) accounted for 58.4 % of the causes of death; hemorrhagic shock was the death cause in 28.4 % and multiple organ failure (MOF)/sepsis in 13.2 % of the patients. However, the distribution of causes of death changed during the period showing a reduction of TBI-related and increase of MOF/sepsis (CTR test trend p < 0.05). Significant predictors of mortality in the whole group were year of admission (p < 0.05), age, hemorrhagic shock and SBP at admission, ISS and GCS, pH and BE (all p < 0.01). In the subgroup of patients that underwent emergency surgery, the same factors confirmed their prognostic value and remained significant as well as the adjunctive parameter of total amount of blood units transfused (p < 0.05). Surgical time (mean 71 min) showed a significant trend towards reduction but did not show significant association with mortality (p = 0.06).

CONCLUSION

Mortality of severe trauma decreased significantly during the last 15 years as well as mean GCS improved whereas mean ISS remained stable. The new safety regulations positively influenced incidence and severity of TBI and seemed to improve the outcomes. ISS seems to be a better predictor of outcome than RTS.

Cause and timing of death in massively transfused trauma patients

BACKGROUND

The purpose of this study was to characterize the cause of death in severely injured trauma patients to define potential responses to resuscitation.

METHODS

Prospective analysis of 190 critically injured patients who underwent massive transfusion protocol (MTP) activation or received massive transfusion (>10 U of packed red blood cells [RBC] per 24 hours). Cause of death was adjudicated into one of four categories as follows: (1) exsanguination, (2) early physiologic collapse, (3) late physiologic collapse, and (4) nonsurvivable injury.

RESULTS

A total 190 patients underwent massive transfusion or MTP with 76 deaths (40% mortality), of whom 72 deaths were adjudicated to one of four categories: 33.3% died of exsanguination, 16.6% died of early physiologic collapse, 11.1% died of late physiologic collapse, while 38.8% died of nonsurvivable injuries. Patients who died of exsanguination were younger and had the highest RBC/fresh frozen plasma ratio (2.97 [2.24]), although the early physiologic collapse group survived long enough to use the most blood products (p < 0.001). The late physiologic collapse group had significantly fewer penetrating injuries, was older, and had significantly more crystalloid use but received a lower RBC/fresh frozen plasma ratio (1.50 [0.42]). Those who were determined to have a nonsurvivable injury had a lower presenting Glasgow Coma Scale (GCS) score, fewer penetrating injuries, and higher initial blood pressure reflecting a preponderance of nonsurvivable traumatic brain injury. The average survival time for patients with potentially survivable injuries was 2.4 hours versus 18.4 hours for nonsurvivable injuries (p < 0.001).

CONCLUSION

Severely injured patients requiring MTP have a high mortality rate. However, no studies to date have addressed the cause of death after MTP. Characterization of cause of death will allow targeting of surgical and resuscitative conduct to allow extension of the physiologic reserve time, therefore rendering previously nonsurvivable injury potentially survivable.

Cause of death and time of death distribution of trauma patients in a Level I trauma centre in the Netherlands

OBJECTIVE

The classical trimodal distribution of trauma deaths describes three peaks of deaths following trauma: immediate, early and late deaths. The aim of this study was to evaluate whether further maturation of the trauma centre and the improvement of survival have had an effect on the time of death distribution and resulted in a shift in causes of death.

METHODS

All trauma patients from 1999 to 2010 who died after arrival in the emergency room and prior to discharge from the hospital were included. Deaths caused by drowning, poisoning and overdose were excluded.

RESULTS

A total of 16,421 trauma patients were admitted to our hospital. 772 (4.7 %) patients died, of which 720 were included in this study. The trauma mechanism was predominantly blunt (94.7 %). 530 patients (73.6 %) had Injury Severity Score (ISS) ≥25. The most frequent causes of death were central nervous system (CNS) injury (59.9 %), exsanguinations (12.9 %) and pneumonia/respiratory insufficiency (8.5 %). The first peak of death was seen in the first hour after arrival at the emergency department; subsequently, a rapid decline was observed and no further peaks were seen. Over the years, we observed a general decrease in deaths due to exsanguination (p = 0.035) and a general increase in deaths due to CNS injury (p = 0.004).

CONCLUSION

The temporal distribution of trauma deaths in our hospital changed as maturation of the trauma centre occurred. There is one peak of trauma deaths in the first hour after admission, followed by a rapid decline; no trimodal distribution was observed. Over time, there was a decrease in exsanguinations and an increase of deaths due to CNS injury.

Chronic alcoholism-mediated impairment in the medulla oblongata: a mechanism of alcohol-related mortality in traumatic brain injury?

Alcohol-related traumatic brain injury (TBI) is a common condition in medical and forensic practice, and results in high prehospital mortality. We investigated the mechanism of chronic alcoholism-related mortality by examining the effects of alcohol on the synapses of the medulla oblongata in a rat model of TBI. Seventy adult male Sprague-Dawley rats were randomly assigned to either ethanol (EtOH) group, EtOH-TBI group, or control groups (water group, water-TBI group). To establish chronic alcoholism model, rats in the EtOH group were given EtOH twice daily (4 g/kg for 2 weeks and 6 g/kg for another 2 weeks). The rats also received a minor strike on the occipital tuberosity with an iron pendulum. Histopathologic and ultrastructure changes and the numerical density of the synapses in the medulla oblongata were examined. Expression of postsynaptic density-95 (PSD-95) in the medulla oblongata was measured by ELISA. Compared with rats in the control group, rats in the chronic alcoholism group showed: (1) minor axonal degeneration; (2) a significant decrease in the numerical density of synapses (p < 0.01); and (3) compensatory increase in PSD-95 expression (p < 0.01). Rats in the EtOH-TBI group showed: (1) high mortality (50%, p < 0.01); (2) inhibited respiration before death; (3) severe axonal injury; and (4) decrease in PSD-95 expression (p < 0.05). Chronic alcoholism induces significant synapse loss and axonal impairment in the medulla oblongata and renders the brain more susceptible to TBI. The combined effects of chronic alcoholism and TBI induce significant synapse and axon impairment and result in high mortality.

Pharmacological preconditioning with erythropoietin attenuates the organ injury and dysfunction induced in a rat model of hemorrhagic shock

Pre-treatment with erythropoietin (EPO) has been demonstrated to exert tissue-protective effects against 'ischemia-reperfusion'-type injuries. This protection might be mediated by mobilization of bone marrow endothelial progenitor cells (EPCs), which are thought to secrete paracrine factors. These effects could be exploited to protect against tissue injury induced in cases where hemorrhage is foreseeable, for example, prior to major surgery. Here, we investigate the effects of EPO pre-treatment on the organ injury and dysfunction induced by hemorrhagic shock (HS). Recombinant human EPO (1000 IU/kg/day i.p.) was administered to rats for 3 days. Rats were subjected to HS on day 4 (pre-treatment protocol). Mean arterial pressure was reduced to 35 ± 5 mmHg for 90 minutes, followed by resuscitation with 20 ml/kg Ringer's lactate for 10 minutes and 50% of the shed blood for 50 minutes. Rats were sacrificed 4 hours after the onset of resuscitation. EPC (CD34(+)/flk-1(+) cell) mobilization was measured following the 3-day pre-treatment with EPO and was significantly increased compared with rats pre-treated with phosphate-buffered saline. EPO pre-treatment significantly attenuated organ injury and dysfunction (renal, hepatic and neuromuscular) caused by HS. In livers from rats subjected to HS, EPO enhanced the phosphorylation of Akt (activation), glycogen synthase kinase-3β (GSK-3β; inhibition) and endothelial nitric oxide synthase (eNOS; activation). In the liver, HS also caused an increase in nuclear translocation of p65 (activation of NF-κB), which was attenuated by EPO. This data suggests that repetitive dosing with EPO prior to injury might protect against the organ injury and dysfunction induced by HS, by a mechanism that might involve mobilization of CD34(+)/flk-1(+) cells, resulting in the activation of the Akt-eNOS survival pathway and inhibition of activation of GSK-3β and NF-κB.

Evaluation of Injuries Caused by Penetrating Chest Traumas in Patients Referred to the Emergency Room

The aim of the study was to determine the frequency of different injuries caused by penetrating chest traumas, and also the cause and type of trauma and its accompanying injuries. This is a cross-sectional descriptive study, carried out on all patients referred to the emergency room of Shahid Bahonar Hospital, Kerman, from March 2000 to September 2008, due to penetrating chest trauma. The required information including age, sex, cause of trauma, type and site of injury, and accompanying injury was obtained and used to fill out a questionnaire and then was analyzed. 828 patients were included in the study; most of them were in the age range of 20-29. Of the patients, 97.6 % were males. The most frequent cause of trauma was stabbing, and the most frequent injuries following the trauma were pneumothorax and hemothorax. Orthopedic trauma was the most frequent accompanying injury. The most commonly used diagnostic method was plain chest radiography. In 93 % of the patients, the chest tube was placed and thoracotomy was performed for 97 % of the patients. Shahid Bahonar Hospital is a referral Trauma Centre and treats large number of chest trauma patients. Most patients need only chest tube placement as a definitive treatment.

Acute respiratory distress syndrome after trauma: development and validation of a predictive model

OBJECTIVE

To determine early clinical predictors of acute respiratory distress syndrome after major traumatic injury and characterize the performance of this acute respiratory distress syndrome prediction model, and two previously published acute respiratory distress syndrome prediction models, in an independent cohort of severely injured patients.

DESIGN

Prospective cohort study.

SETTING

University-affiliated level I trauma center in Seattle, WA, and nine hospitals participating in the Inflammation and Host Response to Injury Consortium.

PATIENTS

Model derivation utilized data from 224 patients participating in a randomized controlled trial. All models were validated in an independent cohort of 1,762 trauma patients.

MEASUREMENTS AND MAIN RESULTS

Variables strongly associated with acute respiratory distress syndrome in bivariate analysis (p<.01) were entered into a multiple logistic regression equation to generate an acute respiratory distress syndrome predictive model. We evaluated the performance of all models using the area under the receiver operator characteristic curve. Acute respiratory distress syndrome occurred in 79 subjects (35%) belonging to the development cohort and in 423 subjects (24%) from the validation cohort. Multivariable predictors of acute respiratory distress syndrome after trauma included subject age, Acute Physiology and Chronic Health Evaluation II Score, injury severity score, and the presence of blunt traumatic injury, pulmonary contusion, massive transfusion, and flail chest injury (area under the receiver operator characteristic curve 0.79 [95% confidence interval 0.73, 0.85]). Validation of the prediction model resulted in an area under the receiver operator characteristic curve of 0.71 (95% confidence interval 0.68, 0.74). Our model's performance in the validation cohort was superior to that of two other published acute respiratory distress syndrome prediction models (0.65 [95% confidence interval 0.63, 0.68] and 0.66 [95% confidence interval 0.64, 0.69], p<.01 for all comparisons).

CONCLUSIONS

Using routinely available clinical data, our prediction model identifies patients at high risk for acute respiratory distress syndrome early after severe traumatic injury. This predictive model could facilitate enrollment of subjects into future clinical trials designed to prevent this serious complication.

Spatial analysis of injury-related deaths in Dallas County using a geographic information system

This study applied a geographic information system (GIS) to identify clusters of injury-related deaths (IRDs) within a large urban county (26 cities; population, 2.4 million). All deaths due to injuries in Dallas County (Texas) in 2005 (N = 670) were studied, including the geographic location of the injury event. Out of 26 cities in Dallas County, IRDs were reported in 19 cities. Geospatial data were obtained from the local governments and entered into the GIS. Standardized mortality ratios (SMR, with 95% CI) were calculated for each city and the county using national age-adjusted rates. Dallas County had significantly more deaths due to homicides (SMR, 1.76; 95% CI, 1.54-1.98) and IRDs as a result of gunshots (SMR, 1.23; 95% CI, 1.09-1.37) than the US national rate. However, this increase was restricted to a single city (the city of Dallas) within the county, while the rest of the 25 cities in the county experienced IRD rates that were either similar to or better than the national rate, or experienced no IRDs. GIS mapping was able to depict high-risk geographic "hot spots" for IRDs. In conclusion, GIS spatial analysis identified geographic clusters of IRDs, which were restricted to only one of 26 cities in the county.

Alcohol acute intoxication before sepsis impairs the wound healing of intestinal anastomosis: rat model of the abdominal trauma patient

Introduction

Most trauma patients are drunk at the time of injury. Up to 2% of traumatized patients develop sepsis, which considerably increases their mortality. Inadequate wound healing of the colonic repair can lead to postoperative complications such as leakage and sepsis.

Objective

To assess the effects of acute alcohol intoxication on colonic anastomosis wound healing in septic rats.

Methods

Thirty six Wistar rats were allocated into two groups: S (induction of sepsis) and AS (alcohol intake before sepsis induction). A colonic anastomosis was performed in all groups. After 1, 3 or 7 days the animals were killed. Weight variations, mortality rate, histopathology and tensile breaking strength of the colonic anastomosis were evaluated.

Results

There was an overall mortality of 4 animals (11.1%), three in the group AS (16.6%) and one in the S group (5.5%). Weight loss occurred in all groups. The colon anastomosis of the AS group didn’t gain strength from the first to the seventh postoperative day. On the histopathological analysis there were no differences in the deposition of collagen or fibroblasts between the groups AS and S.

Conclusion

Alcohol intake increased the mortality rate three times in septic animals. Acute alcohol intoxication delays the acquisition of tensile strength of colonic anastomosis in septic rats. Therefore, acute alcohol intoxication before sepsis leads to worse prognosis in animal models of the abdominal trauma patients.

Patterns of Trauma Deaths in an Accident and Emergency Unit

Introduction:

Trauma is a leading cause of death in most countries. Different patterns of trauma deaths are recorded in different countries. The purpose of this study was to evaluate retrospectively the pattern of trauma deaths in the emergency unit of a University Teaching Hospital in Nigeria.

Methods:

This is a descriptive, retrospective study. The data were obtained from patient case files and nurses'records. The data abstracted included age, sex, cause of trauma/death, parts of the body injured, time of death, andthe duration of stay in the Accident and Emergency Unit (AEU).

Results:

A total of 5,537 cases presented to the AEU of the University of Benin Teaching Hospital between 01 January 2001 and 31 December 2004. Of these, 5,446 were due to trauma (98.4%). A total of 127 patients died (case fatality rate: 2.3%). Of the deaths, 81.9% were males. Motor vehicle crashes were the most frequent cause (54.3%), and drowning was the least common cause of trauma (0.8%). The most frequently injured region of the body was the head and neck (53.4%). A total of 67.4% of the deaths occurred within six hours of presentation to the AEU.

Conclusions:

There is a great need for improved road safety, adequate pre-hospital medical care, and prompt transfer services for victims of trauma.

Determination of efficacy of novel modified chitosan sponge dressing in a lethal arterial injury model in swine

BACKGROUND

Chitosan is a functional biopolymer that has been widely used as a hemostat. Recently, its efficacy has been questioned due to clinical failures as a result of poor adhesiveness. The purpose of this study was to compare, in a severe groin injury model in swine, the hemostatic properties of an unmodified standard chitosan sponge with standard gauze dressing and a novel hydrophobically modified (hm) chitosan sponge. Previous studies have demonstrated that hm-chitosan provides greatly enhanced cellular adhesion and hemostatic effect via noncovalent insertion of hydrophobic pendant groups into cell membranes.

METHODS

Twenty-four Yorkshire swine were randomized to receive hm-chitosan (n = 8), unmodified chitosan (n = 8), or standard Accu-Sorb gauze dressing (n = 8) for hemostatic control. A complex groin injury involving arterial puncture (4.4-mm punch) of the femoral artery was made after splenectomy. After 30 seconds of uncontrolled hemorrhage, the randomized dressing was applied and compression was held for 3 minutes. Fluid resuscitation was initiated to achieve and maintain the baseline mean arterial pressure and the wound was inspected for bleeding. Failure of hemostasis was defined as pooling of blood outside the wound. Animals were then monitored for 180 minutes and surviving animals were killed.

RESULTS

Blood loss before treatment was similar between groups (p < 0.1). Compared with the hm-chitosan sponge group, which had no failures, the unmodified chitosan sponge group and the standard gauze group each had eight failures over the 180-minute observation period. For the unmodified chitosan sponge failures, six of which provided initial hemostasis, secondary rebleeding was observed 44 minutes ± 28 minutes after application. Standard gauze provided no initial hemostasis after the 3-minute compression interval.

CONCLUSIONS

Hm-chitosan is superior to unmodified chitosan sponges (p < 0.001) or standard gauze for controlling bleeding from a lethal arterial injury. The hm-chitosan technology may provide an advantage over native chitosan-based dressings for control of active hemorrhage.

Localized control of exsanguinating arterial hemorrhage: an experimental model

To develop an arterial injury model for testing hemostatic devices at well-defined high and low bleeding rates.

MATERIAL AND METHOD

A side-hole arterial injury was created in the carotid artery of sheep. Shed blood was collected in a jugular venous reservoir and bleeding rate at the site of arterial injury was controlled by regulating outflow resistance from the venous reservoir. Two models were studied: uncontrolled exsanguinating hemorrhage and bleeding at controlled rates with blood return to maintain hemodynamic stability. Transcutaneous Duplex ultrasound was used to characterize ultrasound signatures at various bleeding rates.

RESULTS

A 2.5 mm arterial side-hole resulted in exsanguinating hemorrhage with an initial bleeding rate of 400 ml/min which, without resuscitation, decreased to below 100 ml/min in 5 minutes. After 17 minutes, bleeding from the injury site stopped and the animal had lost 60% of total blood volume. Reinfusion of shed blood maintained normal hemodynamics and both high and low bleeding rates could be maintained without hemorrhagic shock. Bleeding rate at the arterial injury site was held at 395±78 ml/min for 8 minutes, 110±11 ml/min for 15 minutes, and 12±1 ml/min for 12 minutes. Doppler flow signatures at the site of injury were characterized by high peak and end-diastolic flow velocities at the bleeding site which varied with the rate of hemorrhage.

CONCLUSION

We have developed a hemodynamically stable model of acute arterial injury which can be used to evaluate diagnostic and treatment methods focused on control of the arterial injury site.

Sympathetic responses to central hypovolemia: new insights from microneurographic recordings

Hemorrhage remains a major cause of mortality following traumatic injury in both military and civilian settings. Lower body negative pressure (LBNP) has been used as an experimental model to study the compensatory phase of hemorrhage in conscious humans, as it elicits central hypovolemia like that induced by hemorrhage. One physiological compensatory mechanism that changes during the course of central hypovolemia induced by both LBNP and hemorrhage is a baroreflex-mediated increase in muscle sympathetic nerve activity (MSNA), as assessed with microneurography. The purpose of this review is to describe recent results obtained using microneurography in our laboratory as well as those of others that have revealed new insights into mechanisms underlying compensatory increases in MSNA during progressive reductions in central blood volume and how MSNA is altered at the point of hemodynamic decompensation. We will also review recent work that has compared direct MSNA recordings with non-invasive surrogates of MSNA to determine the appropriateness of using such surrogates in assessing the clinical status of hemorrhaging patients.

Thrombelastography-identified coagulopathy is associated with increased morbidity and mortality after traumatic brain injury

BACKGROUND

The purpose of this study was to determine the relationship between coagulopathy and outcome after traumatic brain injury.

METHODS

Patients admitted with a traumatic brain injury were enrolled prospectively and admission blood samples were obtained for kaolin-activated thrombelastogram and standard coagulation assays. Demographic and clinical data were obtained for analysis.

RESULTS

Sixty-nine patients were included in the analysis. A total of 8.7% of subjects showed hypocoagulability based on a prolonged time to clot formation (R time, > 9 min). The mortality rate was significantly higher in subjects with a prolonged R time at admission (50.0% vs 11.7%). Patients with a prolonged R time also had significantly fewer intensive care unit-free days (8 vs 27 d), hospital-free days (5 vs 24 d), and increased incidence of neurosurgical intervention (83.3% vs 34.9%).

CONCLUSIONS

Hypocoagulability as shown by thrombelastography after traumatic brain injury is associated with worse outcomes and an increased incidence of neurosurgical intervention.

Achieving hemostasis with topical hemostats: making clinically and economically appropriate decisions in the surgical and trauma settings

Achieving hemostasis is a crucial focus of clinicians working in surgical and trauma settings. Topical hemostatic agents-including mechanical hemostats, active hemostats, flowable hemostats, and fibrin sealants-are frequently used in efforts to control bleeding, and new options such as hemostatic dressings, initially used in combat situations, are increasingly being used in civilian settings. To achieve successful hemostasis, a number of vital factors must be considered by surgeons and perioperative nurses, such as the size of the wound; bleeding severity; and the efficacy, possible adverse effects, and method of application of potential hemostatic agents. Understanding how and when to use each of the available hemostatic agents can greatly affect clinical outcomes and help to limit the overall cost of treatment.