30 years of polytrauma care: An analysis of the change in strategies and results of 4849 cases treated at a single institution

Renal protection after hemorrhagic shock in rats: Possible involvement of SUMOylation

Hemorrhagic shock (HS), a leading cause of preventable death, is characterized by severe blood loss and inadequate tissue perfusion. Reoxygenation of ischemic tissues exacerbates organ damage through ischemia-reperfusion injury. SUMOylation has been shown to protect neurons after stroke and is upregulated in response to cellular stress. However, the role of SUMOylation in organ protection after HS is unknown. This study aimed to investigate SUMOylation-mediated organ protection following HS. Male Wistar rats were subjected to HS (blood pressure of 40 ± 2 mmHg, for 90 min) followed by reperfusion. Blood, kidney, and liver samples were collected at various time points after reperfusion to assess organ damage and investigate the profile of SUMO1 and SUMO2/3 conjugation. In addition, human kidney cells (HK-2), treated with the SUMOylation inhibitor TAK-981 or overexpressing SUMO proteins, were subjected to oxygen and glucose deprivation to investigate the role of SUMOylation in hypoxia/reoxygenation injury. The animals presented progressive multiorgan dysfunction, except for the renal system, which showed improvement over time. Compared to the liver, the kidneys displayed distinct patterns in terms of oxidative stress, apoptosis activation, and tissue damage. The global level of SUMO2/3 in renal tissue was also distinct, suggesting a differential role. Pharmacological inhibition of SUMOylation reduced cell viability after hypoxia-reoxygenation damage, while overexpression of SUMO1 or SUMO2 protected the cells. These findings suggest that SUMOylation might play a critical role in cellular protection during ischemia-reperfusion injury in the kidneys, a role not observed in the liver. This difference potentially explains the renal resilience observed in HS animals when compared to other systems.

[Application of artificial intelligence systems in the emergency room : Do the communication patterns give indications for possible starting points? An observational study]

BACKGROUND

High expectations are currently attached to the application of artificial intelligence (AI) in the resuscitation room treatment of trauma patients with respect to the development of decision support systems. No data are available regarding possible starting points for AI-controlled interventions in resuscitation room treatment.

OBJECTIVE

Do information request behavior and quality of communication indicate possible starting points for AI applications in the emergency room?

MATERIAL AND METHODS

A 2‑stage qualitative observational study: 1. Development of an observation sheet based on expert interviews that depicts the following six relevant topics: situational factors (course of accident, environment), vital parameters, treatment-specific Information (treatment carried out). trauma-specific factors (injury patterns), medication, special features of the patient (anamnesis, etc.) 2. Observational study Which topics were inquired about during emergency room treatment? Was the exchange of information complete?

RESULTS

There were 40 consecutive observations in the emergency room. A total of 130 questions: 57/130 inquiries about medication/treatment-specific Information and vital parameters, 19/28 of which were inquiries about medication. Questions about injury-related parameters 31/130 with 18/31 regarding injury patterns, course of accident (8/31) and type of accident (5/31). Questions about medical or demographic background 42/130. Within this group, pre-existing illnesses (14/42) and demographic background (10/42) were the most frequently asked questions. Incomplete exchange of information was found in all six subject areas.

CONCLUSION

Questioning behavior and incomplete communication indicate a cognitive overload. Assistance systems that prevent cognitive overload can maintain decision-making abilities and communication skills. Which AI methods can be used requires further research.

Continuous improvement in optimizing the timing of axial, hip, and femoral fracture fixation

Benefits of early stabilization of femoral shaft fractures, in mitigation of pulmonary and other complications, have been recognized over the past decades. Investigation into the appropriate level of resuscitation, and other measures of readiness for definitive fixation, versus a damage control strategy have been ongoing. These principles are now being applied to fractures of the thoracolumbar spine, pelvis, and acetabulum. Systems of trauma care are evolving to encompass attention to expeditious and safe management of not only multiply injured patients with these major fractures, but also definitive care for hip and periprosthetic fractures, which pose a similar burden of patient recumbency until stabilized. Future directions regarding refinement of patient resuscitation, assessment, and treatment are anticipated, as is the potential for data sharing and registries in enhancing trauma system functionality.

Treatment management and outcome of polytraumatized patients in a German certified trauma center - comparing standard versus maximum care

German hospitals are classified as basic, standard and maximum care facilities within the German trauma networks. The Municipal Hospital Dessau was upgraded in 2015 as a maximum care provider. The aim of this study is to investigate whether a change in treatment management and outcome of polytraumatized patients has occurred afterwards. The study compared polytraumatized patients, treated in the Dessau Municipal Clinic as a standard care facility (DessauStandard) from 2012-2014 vs. those treated in the Dessau Municipal Clinic as a maximum care facility (DessauMax) from 2016-2017. Data of the German Trauma Register were analysed using the chi-square test, t-test and odds ratios with 95% confidence intervals.In DessauMax (238 patients; Ø 54 years, SD 22.3; ♂ 160, ♀ 78), the shock room time with 40.7 min (SD 21.4) was shorter than in DessauStandard (206 patients; Ø 56.1 years, SD 22.1; ♂ 133, ♀ 73 ) with 49 min (SD 25.1) (p=0.001). The transfer rate of 1.3% (n=3) to another hospital was lower in DessauMax (p=0.01). DessauStandard had 9 (4%) thromboembolic events and DessauMax 3 (1.3%) (p=0.7). Multiorgan failure was more common in DessauStandard, (16%) than in DessauMax (1.3%; p=0,001). DessauStandard showed a mortality of 13.1% (n=27), and DessauMax 9.2% (n=22) (p=0.22; OR=0.67, 95% CI, 0.37-1.23). The GOS in DessauMax (4.5, SD 1.2) was higher than in DessauStandard (4.1, SD 1.3) (p=0.002).The Dessau Municipal Clinic as a maximum care facility has achieved improved shock room time, fewer complications, lower mortality and an improved outcome.

The impact of upper-extremity injuries on polytrauma patients at a level 1 trauma center

BACKGROUND

Upper-extremity injuries often lead to long-term problems in function and quality of life in patients. However, not much is known about the effects in polytrauma patients. This study aimed to describe the upper-extremity injuries in polytrauma patients and to compare self-reported disability and quality of life in polytrauma patients with vs. without upper-extremity injuries.

METHODS

We performed a retrospective cohort study of adult patients with an Injury Severity Score ≥ 16 admitted to Erasmus MC between January 1, 2007, and December 31, 2016. Patients were asked to complete the Disabilities of the Arm, Shoulder and Hand, Short Form 36, and EuroQol-5D questionnaires. Details on injuries, treatment, and clinical outcome were collected from the national trauma registry and medical files. Characteristics and self-reported outcomes of polytrauma patients with vs. without upper-extremity injuries were compared.

RESULTS

In a cohort of 3469 trauma patients, 1246 (36.5%) had upper-extremity injuries. Of these, 278 (22.0%) had severe injuries (Abbreviated Injury Scale score ≥ 3). Upper-extremity injuries were associated with a longer hospitalization (median, 12 days vs. 8 days; P < .001), longer intensive care unit stay (median, 5 days vs. 4 days; P = .005), and lower mortality rate (14.6% vs. 23.9%, P < .001). Among the 598 patients who completed the questionnaires, no differences in the physical component summary score (47 vs. 48, P = .181) and mental component summary score (54 vs. 53, P = .315) of the Short Form 36 questionnaire, as well as the utility score (0.82 vs. 0.85, P = .101) and visual analog scale score (80 vs. 80, P = .963) of the EuroQol-5D questionnaire, were found. However, patients with upper-extremity injuries showed a minor increase in disability in the Disabilities of the Arm, Shoulder and Hand score (9.2 vs. 4.2, P = .023).

CONCLUSION

Upper-extremity injuries in polytrauma patients are associated with a longer hospitalization, longer intensive care unit stay, and reduced mortality rate, as well as a minor increase in long-term disability.

25-Year experience with adult polytraumatized patients in a European level 1 trauma center: polytrauma between 1995 and 2019. What has changed? A retrospective cohort study

PURPOSE

To analyze the changes of the clinical characteristics, injury patterns, and mortality rates of polytraumatized patients within the past 25 years in a European Level I trauma center.

METHODS

953 consecutive polytraumatized patients treated at a single-level 1 trauma center between January 1995 and December 2019 were enrolled retrospectively. Polytrauma was defined as AIS ≥ 3 points in at least two different body regions. Retrospective data analysis on changes of clinical characteristics and mortality rates over time.

RESULTS

A significant increase of the average age by 2 years per year of the study could be seen with a significant increase of geriatric patients over time. No changes of the median Injury Severity Score (ISS) could be seen over time, whereas the ISS significantly decreased by patient's year. The rates of concomitant severe traumatic brain injury (TBI) remained constant over time, and did not increase with rising age of the patients. Although, the mortality rate remained constant over time the relative risk of overall in-hospital mortality increased by 1.7% and the relative risk of late-phase mortality increased by 2.2% per patient's year.

CONCLUSION

The number of polytraumatized patients remained constant over the 25-year study period. Also, the mortality rates remained stable over time, although a significant increase of the average age of polytraumatized patients could be seen with stable injury severity scores. Severe TBI and age beyond 65 years remained independent prognostic factors on the late-phase survival of polytraumatized patients.

TRIAL REGISTRATION

NCT04723992.

LEVEL OF EVIDENCE

Prognostic study, level III.

Nationwide improvements in geriatric mortality due to traumatic brain injury in Japan

BACKGROUND

Traumatic brain injury (TBI), both isolated and in combination with extracranial lesions, is a global health problem associated with high mortality. Among various risk factors for poor clinical outcomes, age is the most important independent predictor of mortality in patients with TBI. TBI-related mortality is expected to increase as the society ages. However, in a super-aged society such as Japan, little is known about the trend of TBI-related mortality among older adults. Herein, we assessed the nationwide trend of the incidence and clinical outcomes of geriatric patients with TBI in Japan using the national Japanese Trauma Data Bank (JTDB) registry.

METHODS

In this retrospective cohort study, cases of TBI (aged ≥65 years) in hospitals registered with the JTDB database between January 2004 and December 2018 were included. In-hospital mortality was the primary outcome, and mortality in the emergency department was the secondary outcome. The odds ratios (ORs) and 95% confidence intervals (CIs) for in-hospital deaths with respect to 3-year periods were assessed using multivariable analysis after adjusting for potential confounders.

RESULTS

The main cause of TBI in older individuals was falls. The proportion of patients who died after hospitalization during the study period decreased markedly from 29.5% (194/657) during 2004-2006 to 14.2% (1309/9240) during 2016-2018 in the isolated TBI group (adjusted OR = 0.42, 95% CI: 0.33-0.53) and from 48.0% (119/248) during 2004-2006 to 21.7% (689/3172) during 2016-2018 in the multiple trauma group (adjusted OR = 0.32, 95% CI: 0.23-0.45). The adjusted ORs for the 3-year increment were 0.84 (95% CI: 0.81-0.88) and 0.78 (95% CI: 0.75-0.83) for the isolated TBI and multiple trauma groups, respectively.

CONCLUSIONS

Using the national JTDB registry, we demonstrated a nationwide reduction in TBI-related mortality. Our findings in the super-aged society of Japan may provide insight for the treatment of geriatric patients with TBI worldwide.

Transcriptomic Changes Within Human Bone Marrow After Severe Trauma

BACKGROUND

Severe trauma is associated with severe systemic inflammation and neuroendocrine activation that is associated with erythroid progenitor growth suppression and refractory anemia. Although distinct transcriptional profiles have been detected in numerous tissue types after trauma, no study has yet characterized this within the bone marrow. This study sought to identify a unique bone marrow transcriptomic response following trauma.

METHODS

In a prospective observational cohort study, bone marrow was obtained from severely injured trauma patients with a hip or femur fracture (n = 52), elective hip replacement patients (n = 33), and healthy controls (n = 11). RNA was isolated from bone marrow using a Purelink RNA mini kit. Direct quantification of mRNA copies was performed by NanoString Technologies on a custom gene panel.

RESULTS

Trauma patients displayed an upregulation of genes encoding receptors known to have inhibitory downstream effects on erythropoiesis, including ferroportin, interleukin-6 (IL-6) receptor, transforming growth factor-beta (TGF-β) receptor, and IL-10, as well as genes involved in innate immunity including toll-like receptor 4 (TLR4)-mediated signaling factors. In contrast, hip replacement patients had downregulated transcription of IL-1β, IL-6, TGF-β, tumor necrosis factor alpha, and the HAMP gene with no change in TLR4-mediated signaling factors.

CONCLUSIONS

A unique transcriptomic response within the bone marrow was identified following severe trauma compared to elective hip replacement. These transcriptomic differences were related to the innate immune response as well as known inhibitors of erythropoiesis. Although confined to just one time point, this differential transcriptional response may be linked to refractory anemia and inflammation after injury.

Psychological outcomes affect functional outcomes in patients with severe pelvic ring fractures

PURPOSE

To evaluate the correlation between post-traumatic functional and psychological outcomes in patients with severe pelvic ring injuries.

METHODS

Forty-four patients who sustained a completely unstable pelvic ring injury (Tile C, AO/OTA 61C) treated in our institution from 2012 to 2017 were included. A telephone interview was performed in 16 of 44 patients to evaluate pelvic functionality, using the Majeed pelvic score, and psychological evaluation, using Hamilton anxiety and depression rating scales.

RESULTS

The mean Injury Severity Score (ISS) was 27 ± 12, and mean GCS at presentation was 13 ± 4. Average time from trauma to interview was 3 years (range, 1-5 years). Mean Majeed pelvic score was 67 ± 22. Majeed sub-scores were pain 19 ± 9, work 10 ± 7, sitting 8 ± 2, sexual intercourse 3 ± 2, walking aids 11 ± 2, gait unaided 9 ± 2, walking distance 8 ± 3. Mean depression and anxiety scores were 16 ± 12 and 17 ± 14, respectively. Significant correlations were observed between functional and psychological outcomes (P < 0.005). Majeed score was negatively correlated with depressive symptoms (r = -0.721, P = 0.002) and anxiety symptoms (r = -0.756, P = 0.001). Depression and anxiety scores were positively correlated (r = 0.945, P < 0.001).

CONCLUSION

Lower functional outcomes in patients with Tile C pelvic injuries were correlated with more severe symptoms of depression and anxiety. We recommend that providers consider and treat patients' mental health condition during posttraumatic recovery.

Initial Experiences of Extracorporeal Membrane Oxygenation for Trauma Patients at a Single Regional Trauma Center in South Korea

Purpose For severe lung injuries or acute respiratory distress syndrome that occurs during critical care due to trauma, extracorporeal membrane oxygenation (ECMO) may be used as a salvage treatment. This study aimed to describe the experiences at a single center with the use of ECMO in trauma patients. Methods We enrolled a total of 25 trauma patients who were treated with ECMO between January 2015 and December 2019 at a regional trauma center. We analyzed and compared patients’ characteristics between survivors and non-survivors through a medical chart review. We also compared the characteristics of patients between direct and indirect lung injury groups. Results The mean age of the 25 patients was 45.9±19.5 years, and 19 patients (76.0%) were male. The mean Injury Severity Score was 26.1±10.1. Ten patients (40.0%) had an Abbreviated Injury Scale (AIS) 3 score of 4, and six patients (24.0%) had an AIS 3 score of 5. There were 19 cases (76.6%) of direct lung injury. The mortality rate was 60.0% (n=15). Sixteen patients (64.0%) received a loading dose of heparin for the initiation of ECMO. There was no significant difference in heparin use between the survivors and non-survivors (70% in survivors vs. 60% in non-survivors, p=0.691). When comparing the direct and indirect lung injury groups, there were no significant differences in variables other than age and ECMO onset time. Conclusions If more evidence is gathered, risk factors and indications will be identified and we expect that more trauma patients will receive appropriate treatment with ECMO.

Chronic critical illness after hypothermia in trauma patients

Objectives

Chronic critical illness (CCI) is a phenotype that occurs frequently in patients with severe injury. Previous work has suggested that inflammatory changes leading to CCI occur early following injury. However, the modifiable factors associated with CCI are unknown. We hypothesized that hypothermia, an early modifiable factor, is associated with CCI.

Methods

To determine the association of hypothermia and CCI, a secondary analysis of the Inflammation and Host Response to Injury database was performed, and subsequently validated on a similar cohort of patients from a single level 1 trauma center from January 2015 to December 2019. Hypothermia was defined as initial body temperature ≤34.5°C. CCI was defined as death or sustained multiorgan failure ≥14 days after injury. Data were analyzed using univariable analyses with Student’s t-test and Pearson’s χ² test, and logistic regression. An arrayed genomic analysis of the transcriptome of circulating immune cells was performed in these patients.

Results

Of the initial 1675 patients, 254 had hypothermia and 1421 did not. On univariable analysis, 120/254 (47.2%) of patients with hypothermia had CCI, compared with 520/1421 (36.6%) without hypothermia who had CCI, p<0.001. On multivariable logistic regression, hypothermia was independently associated with CCI, OR 1.61 (95% CI 1.17 to 2.21) but not mortality. Subsequent validation in 1264 patients of which 172 (13.6%) were hypothermic, verified that hypothermia was independently associated with CCI on multivariable logistic regression, OR 1.84 (95% CI 1.21 to 2.41). Transcriptomic analysis in hypothermic and non-hypothermic patients revealed unique cellular-specific genomic changes to only circulating monocytes, without any distinct effect on neutrophils or lymphocytes.

Conclusions

Hypothermia is associated with the development of CCI in severely injured patients. There are transcriptomic changes which indicate that the changes induced by hypothermia may be associated with persistent CCI. Thus, early reversal of hypothermia following injury may prevent the CCI.

Level of evidence

III.

The ROX index as a predictor of standard oxygen therapy outcomes in thoracic trauma

BACKGROUND

Thoracic trauma is commonplace and accounts for 50-70% of the injuries found in severe trauma. Little information is available in the literature as to timing of endotracheal intubation. The main objective of this study was to assess the accuracy of the ROX index in predicting successful standard oxygen (SO) therapy outcomes, and in pre-empting intubation.

METHODS

Patient selection included all thoracic trauma patients treated with standard oxygen who were admitted to a Level I trauma center between January 1, 2013 and April 30, 2020. Successful standard SO outcomes were defined as non-requirement of invasive mechanical ventilation within the 7 first days after thoracic trauma.

RESULTS

One hundred seventy one patients were studied, 49 of whom required endotracheal intubation for acute respiratory distress (28.6%). A ROX index score ≤ 12.85 yielded an area under the ROC curve of 0.88 with a 95% CI [0.80-0.94], 81.63sensitivity, 95%CI [0.69-0.91] and 88.52 specificity, 95%CI [0.82-0.94] involving a Youden index of 0.70. Patients with a median ROX index greater than 12.85 within the initial 24 h were less likely to require mechanical ventilation within the initial 7 days of thoracic trauma.

CONCLUSION

We have shown that a ROX index greater than 12.85 at 24 h was linked to successful standard oxygen therapy outcomes in critical thoracic trauma patients. It is our belief that an early low ROX index in the initial phase of trauma should heighten vigilance on the part of the attending intensivist, who has a duty to optimize management.

Extracorporeal support for trauma: A trauma quality improvement project (TQIP) analysis in patients with acute respiratory distress syndrome

INTRODUCTION

The use of extracorporeal membrane oxygenation (ECMO) in trauma patients with severe acute respiratory distress syndrome (ARDS) continues to evolve. The objective of this study was to perform a comparative analysis of trauma patients with ARDS who received ECMO to a propensity matched cohort of patients who underwent conventional management.

METHODS

The Trauma Quality Improvement Program (TQIP) database was queried from 2013 to 2016 for all patients with ARDS and those who received ECMO. Demographics, as well as clinical, injury, intervention, and outcome data were collected and analyzed. Patients with ARDS were divided into two groups, those who received ECMO and those who did not. A propensity score analysis was performed using the following criteria: age, gender, vital signs (HR, SBP) and GCS on admission, Injury Severity Score (ISS), and Abbreviated Injury Scale (AIS) score in several body regions. Outcomes between the groups were subsequently compared using univariate as well as Cox regression analyses. Secondary outcomes such as hospitalization (HLOS), ICU length-of-stay (LOS) and ventilation days stratified for patient demographics, timing of ECMO and anticoagulation status were compared.

RESULTS

Over the 3-year study period, 8990 patients with ARDS were identified from the TQIP registry. Following exclusion, 3680 were included in the final analysis, of which 97 (2.6%) received ECMO. On univariate analysis following matching, patients who underwent ECMO had lower overall hospital mortality (23 vs 50%, p < 0.001) with higher rates of complications (p < 0.005), including longer HLOS. In those undergoing ECMO, early initiation (<7 days) was associated with shorter HLOS, ICU LOS, and fewer ventilator days. No difference was observed between the two groups with regard to anticoagulation.

CONCLUSION

Extracorporeal membrane oxygenation use in trauma patients with ARDS may be associated with improved survival, especially for young patients with thoracic injuries, early in the course of ARDS. Anticoagulation while on circuit was not associated with increased risk of hemorrhage or mortality, even in the setting of head injuries. The mortality benefit suggested with ECMO comes at the expense of a potential increase in complication rate and prolonged hospitalization.

Process related decisions and in-hospital transport times in polytrauma patients benefit from 24/7 in-house presence of trauma surgeons

BACKGROUND

Time and cause of death in polytrauma has shifted due to improvements in trauma and critical care. These include logistical improvements with dedicated trauma teams and in-house trauma surgeons. This study investigated in-hospital transport times and influence of process related decisions on mortality in polytrauma patients.

STUDY DESIGN

A 6.5-year prospective study included consecutive polytrauma patients ≥15 years admitted to a Level-1 Trauma Center ICU with 24/7 in-house trauma surgeons. Demographics, physiologic parameters, pre- and in-hospital transport times were prospectively collected. Data are presented as median(IQR).

RESULTS

391 patients were included with median ISS of 29(22-36). 82 patients(21%) had a SBP≤90 mmHg on arrival in ED. 44 patients went from ED directly to OR for urgent surgery, all others had CT prior to OR and/or ICU. Patients who went directly to OR from ED had median transport time of 28(23-37) min. Patients who had CT after ED had median transport time of 31(25-42) min. 74(19%) patients died, majority caused by TBI(70%). Ten patients died <24 h after trauma (4 hemorrhage,3 TBI,2 ischemia,1 cardiac injury), 9 of them went straight to OR from ED. Death could possibly have been prevented in 1 patient (1%) who later died of hemorrhage but went to CT before urgent surgery.

CONCLUSION

In-hospital transport times from ED were half an hour regardless of the following destination (OR/CT). Decisions for transport order based on clinical signs in primary survey were rapid and accurate. This could be attributed to dedicated trauma teams and 24/7 physical presence of trauma surgeons.

Synergistic Effects of Forensic Medicine and Traumatology: Comparison of Clinical Diagnosis Autopsy Findings in Trauma-Related Deaths

BACKGROUND

Trauma is the third leading cause of death worldwide after cardiovascular and oncologic diseases. Predominant causes of trauma-related death (TD) are severe traumatic brain injury (sTBI), hemorrhagic shock, and multiple organ failure. An analysis of TD is required in order to review the quality of trauma care and grasp how well the entire trauma network functions, especially for the most severely injured patients. Furthermore, autopsies not only reveal hidden injuries, but also verify clinical assumed causes of death.

MATERIAL

During the study period of 3 years, a total of 517 trauma patients were admitted to our supraregional University Centre of Orthopaedics and Traumatology in Dresden. 13.7% (71/517) of the patients died after trauma, and in 25 cases (35.2%), a forensic autopsy was instructed by the federal prosecutor. The medical records, death certificates, and autopsy reports were retrospectively evaluated and the clinical findings matched to autopsy results.

RESULTS

The observed mortality rates (13.7%) were 4.2% less than expected by the calculated RISC II probability of survival (mortality rate of 17.9%). The most frequent trauma victims were due to falls >3 m (n = 29), followed by traffic accidents (n = 28). The median ISS was 34, IQR 25, and the median New ISS (NISS) was 50, IQR 32. Locations of death were in emergency department (23.9%), ICU (73.2%), OR and ward (1.4%, respectively). Clinicians classified 47.9% of deaths due to sTBI (n = 34), followed by 9.9% thoracic trauma and multiple organ failure (n = 7), 8.4% multiple trauma (n = 6), and 2.8% hypoxia and exsanguination (n = 2). In 18.3%, cases were unspecific or other causes of death recorded on the death certificates. Evident differences with evident clinical consequences were ascertained in 4% (n = 1) and marginal clinical consequences in 24% (6/25). In 16% (4/25), marginal differences with minor forensic consequences were revealed.

CONCLUSIONS

Even in a supraregional trauma center, specialized in multiple trauma management (4.2% survival benefit), room for improvement exists in more than a quarter of all casualties. This underlines the need for higher autopsy rates to uncover missed injuries and to understand the pathomechanism in each trauma fatality. This would also help to uncover potential insufficiencies in clinical routines with regard to diagnostics. The interdisciplinary cooperation of trauma surgeons and forensic pathologists can increase the quality of trauma patient care.

Different experimental multiple trauma models induce comparable inflammation and organ injury

Multiple injuries appear to be a decisive factor for experimental polytrauma. Therefore, our aim was to compare the inflammatory response and organ damage of five different monotrauma with three multiple trauma models. For this, mice were randomly assigned to 10 groups: Healthy control (Ctrl), Sham, hemorrhagic shock (HS), thoracic trauma (TxT), osteotomy with external fixation (Fx), bilateral soft tissue trauma (bsTT) or laparotomy (Lap); polytrauma I (PT I, TxT + HS + Fx), PT II (TxT + HS + Fx + Lap) and one multi-trauma group (MT, TxT + HS + bsTT + Lap). The inflammatory response and organ damage were quantified at 6 h by analyses of IL-6, IL-1β, IL-10, CXCL1, SAA1, HMGB1 and organ injury. Systemic IL-6 increased in all mono and multiple trauma groups, while CXCL1 increased only in HS, PT I, PT II and MT vs. control. Local inflammatory response was most prominent in HS, PT I, PT II and MT in the liver. Infiltration of inflammatory cells into lung and liver was significant in all multiple trauma groups vs. controls. Hepatic and pulmonary injury was prominent in HS, PT I, PT II and MT groups. These experimental multiple trauma models closely mimic the early post-traumatic inflammatory response in human. Though, the choice of read-out parameters is very important for therapeutic immune modulatory approaches.

Global changes in mortality rates in polytrauma patients admitted to the ICU-a systematic review

Background

Many factors of trauma care have changed in the last decades. This review investigated the effect of these changes on global all-cause and cause-specific mortality in polytrauma patients admitted to the intensive care unit (ICU). Moreover, changes in trauma mechanism over time and differences between continents were analyzed.

Main body

A systematic review of literature on all-cause mortality in polytrauma patients admitted to ICU was conducted. All-cause and cause-specific mortality rates were extracted as well as trauma mechanism of each patient. Poisson regression analysis was used to model time trends in all-cause and cause-specific mortality.

Thirty studies, which reported mortality rates for 82,272 patients, were included and showed a decrease of 1.8% (95% CI 1.6–2.0%) in all-cause mortality per year since 1966. The relative contribution of brain injury-related death has increased over the years, whereas the relative contribution of death due to multiple organ dysfunction syndrome (MODS), acute respiratory distress syndrome, and sepsis decreased. MODS was the most common cause of death in North America, and brain-related death was the most common in Asia, South America, and Europe. Penetrating trauma was most often reported in North America and Asia.

Conclusions

All-cause mortality in polytrauma patients admitted to the ICU has decreased over the last decades. A shift from MODS to brain-related death was observed. Geographical differences in cause-specific mortality were present, which may provide region-specific learning possibilities resulting in improvement of global trauma care.

Validation of reference genes for expression analysis in a murine trauma model combining traumatic brain injury and femoral fracture

Systemic and local posttraumatic responses are often monitored on mRNA expression level using quantitative real-time PCR (qRT-PCR), which requires normalisation to adjust for confounding sources of variability. Normalisation requests reference (housekeeping) genes stable throughout time and divergent experimental conditions in the tissue of interest, which are crucial for a reliable and reproducible gene expression analysis. Although previous animal studies analysed reference genes following isolated trauma, this multiple-trauma gene expression analysis provides a notable study analysing reference genes in primarily affected (i.e. bone/fracture callus and hypothalamus) and secondarily affected organs (i.e. white adipose tissue, liver, muscle and spleen), following experimental long bone fracture and traumatic brain injury. We considered tissue-specific and commonly used top-ranked reference candidates from different functional groups that were evaluated applying the established expression stability analysis tools NormFinder, GeNorm, BestKeeper and RefFinder. In conclusion, reference gene expression in primary organs is highly time point as well as tissue-specific, and therefore requires careful evaluation for qRT-PCR analysis. Furthermore, the general application of Ppia, particularly in combination with a second reference gene, is strongly recommended for the analysis of systemic effects in the case of indirect trauma affecting secondary organs through local and systemic pathophysiological responses.

Missed Skeletal Trauma Detected by Whole Body Bone Scan in Patients with Traumatic Brain Injury

OBJECTIVE

Unclear mental state is one of the major factors contributing to diagnostic failure of occult skeletal trauma in patients with traumatic brain injury (TBI). The aim of this study was to evaluate the overlooked co-occurring skeletal trauma through whole body bone scan (WBBS) in TBI.

METHODS

A retrospective study of 547 TBI patients admitted between 2015 and 2017 was performed to investigate their cooccurring skeletal injuries detected by WBBS. The patients were divided into three groups based on the timing of suspecting skeletal trauma confirmed : 1) before WBBS (pre-WBBS); 2) after the routine WBBS (post-WBBS) with good mental state and no initial musculoskeletal complaints; and 3) after the routine WBBS with poor mental state (poor MS). The skeletal trauma detected by WBBS was classified into six skeletal categories : spine, upper and lower extremities, pelvis, chest wall, and clavicles. The skeletal injuries identified by WBBS were confirmed to be simple contusion or fractures by other imaging modalities such as X-ray or computed tomography (CT) scans. Of the six categorizations of skeletal trauma detected as hot uptake lesions in WBBS, the lesions of spine, upper and lower extremities were further statistically analyzed to calculate the incidence rates of actual fractures (AF) and actual surgery (AS) cases over the total number of hot uptake lesions in WBBS.

RESULTS

Of 547 patients with TBI, 112 patients (20.4 %) were presented with TBI alone. Four hundred and thirty-five patients with TBI had co-occurring skeletal injuries confirmed by WBBS. The incidences were as follows : chest wall (27.4%), spine (22.9%), lower extremities (20.2%), upper extremities (13.5%), pelvis (9.4%), and clavicles (6.3%). It is notable that relatively larger number of positive hot uptakes were observed in the groups of post-WBBS and poor MS. The percentage of post-WBBS group over the total hot uptake lesions in upper and lower extremities, and spines were 51.0%, 43.8%, and 41.7%, respectively, while their percentages of AS were 2.73%, 1.1%, and 0%, respectively. The percentages of poor MS group in the upper and lower extremities, and spines were 10.4%, 17.4%, and 7.8%, respectively, while their percentages of AS were 26.7%, 14.2%, and 11.1%, respectively. There was a statistical difference in the percentage of AS between the groups of post-WBBS and poor MS (p=0.000).

CONCLUSION

WBBS is a potential diagnostic tool in understanding the skeletal conditions of patients with head injuries which may be undetected during the initial assessment.

[Care Management for Polytrauma Patients in a Level-1 Trauma Centre]

Care Management for Polytrauma Patients in a Level-1 Trauma Centre Abstract. In our level-1 trauma institution, polytrauma patients with an Injury Severity Score of 16 or higher are facing waiting times for transfer to a rehabilitation facility, causing a negative financial outcome for our institution. The purpose of this study is to stimulate rapid transfer to a rehabilitation facility. In a single-centre case study, care management for (poly)trauma patients was started to ensure time-directed treatment for trauma patients related to Diagnosis-Related Groups (DRG). In the period of 2013-2018 there was an increase in trauma admissions up to 14 % (n = 16 157) with a mean length of hospital stay of 6.4 days, together with a reduction in the number of trauma bed capacity from 50 to 42. In relation to the DRGs, regular trauma patients who were not in need of a stationary rehabilitation facility stayed in line with the expected time of hospital stay. But (poly)trauma patients (n = 1831) with the need of a stationary stay in a rehabilitation centre were faced with waiting times before they could be transferred. The average excess waiting time in relation to DRG for polytrauma patients was 5.1 days. Trauma patients for a rehabilitation centre have a higher Case Mix Index (CMI) compared to those who do not require inpatient rehabilitation (4.22 versus 1.04, p <0.0001). With about 280 trauma patients annually waiting an extra 5.1 days for transfer to a rehabilitation facility, the financial burden for our department amounts to Swiss francs 885,360 without reimbursement. Since no extra bed capacities in rehabilitation facilities are available in our area, it may be advised to set up an early in-hospital trauma rehabilitation program in a level-1 trauma centre in order to reduce financial loss.

Polymicrobial Sepsis Impairs Antigen-Specific Memory CD4 T Cell-Mediated Immunity

Patients who survive sepsis display prolonged immune dysfunction and heightened risk of secondary infection. CD4 T cells support a variety of cells required for protective immunity, and perturbations to the CD4 T cell compartment can decrease overall immune system fitness. Using the cecal ligation and puncture (CLP) mouse model of sepsis, we investigated the impact of sepsis on endogenous Ag-specific memory CD4 T cells generated in C57BL/6 (B6) mice infected with attenuated Listeria monocytogenes (Lm) expressing the I-A^b-restricted 2W1S epitope (Lm-2W). The number of 2W1S-specific memory CD4 T cells was significantly reduced on day 2 after sepsis induction, but recovered by day 14. In contrast to the transient numerical change, the 2W1S-specific memory CD4 T cells displayed prolonged functional impairment after sepsis, evidenced by a reduced recall response (proliferation and effector cytokine production) after restimulation with cognate Ag. To define the extent to which the observed functional impairments in the memory CD4 T cells impacts protection to secondary infection, B6 mice were infected with attenuated Salmonella enterica-2W (Se-2W) 30 days before sham or CLP surgery, and then challenged with virulent Se-2W after surgery. Pathogen burden was significantly higher in the CLP-treated mice compared to shams. Similar reductions in functional capacity and protection were noted for the endogenous OVA₃₂₃-specific memory CD4 T cell population in sepsis survivors upon Lm-OVA challenge. Our data collectively show CLP-induced sepsis alters the number and function of Ag-specific memory CD4 T cells, which contributes (in part) to the characteristic long-lasting immunoparalysis seen after sepsis.

DOES THE TERM OF DEFINITIVE OSTEOSYNTHESIS OF MULTIPLE LONG BONE FRACTURES OF LOWER EXTREMITIES IMPACT ON TREATMENT OUTCOMES IN POLYTRAUMA PATIENTS

The aim: to determine the timing impact of definitive multiple long bone fracture osteosynthesis of lower extremities on complications development, duration of Mechanical Ventilation (MV), Length of Stay in Intensive Care Unit (LOS-ICU), Hospital length of Stay (H-LOS) in patients with polytrauma treated according to Damage Control Orthopedics (DCO). Materials and methods: a prospective controlled non-randomized trial in parallel groups conducted in polytrauma department of Kyiv City Clinical Hospital No. 17 from February 2016 to January 2020, which included 107 adult patients with polytrauma, multiple long bone fractures of lower extremities, one of which femur treated according to DCO. The patients were divided into two groups: Group I included 51 patients who underwent definitive osteosynthesis of long bone fractures of lower extremities after patient condition stabilization ≥24 hours ≤5 days; Group II included 56 patients who underwent definitive osteosynthesis of long bone fractures of lower extremities during the period >5 days after injury. Results: there were no statistically significant differences between Group I and Group II patients in demographics, injury mechanism, trauma severity and general patient condition. Group I patients who underwent osteosynthesis from 2nd to 5th days after injury had lower pneumonia incidence, compared to Group II patients (17.6 % vs. 26.8 %, p=0.047), shorter MV duration (9.3±6.9 vs. 14.9±9.1, p=0.048), ICU-LOS (13.5±8.3 vs. 19.1±11.0, p=0.037), and H-LOS (30.3±13.9 vs. 38.9±15.5, p=0.046). Conclusion: performing definitive multiple fracture osteosynthesis of lower extremity long bones after polytrauma patient stabilization from 2nd to 5th days after injury allowed to reduce the frequency of pneumonia, shorten the duration of MV, LOS-ICU and H-LOS, compared with its implementation after 5th days

Regulatory T Cells Modulate CD4 Proliferation after Severe Trauma via IL-10

Objective: Severely injured patients frequently develop an immunological imbalance following the traumatic insult, which might result in infectious complications evoked by a persisting immunosuppression. Regulatory T cells (Tregs) maintain the immune homeostasis by suppressing proinflammatory responses, however, their functionality after trauma is unclear. Here, we characterized the role of Tregs in regulating the proliferation of CD4⁺ lymphocytes in traumatized patients (TP). Methods: Peripheral blood was obtained daily from 29 severely injured TP (Injury Severity Score, ISS ≥16) for ten days following admission to the emergency department (ED). Ten healthy volunteers (HV) served as controls. The frequency and activity of Tregs were assessed by flow cytometry. Proliferation of CD4⁺ cells was analyzed either in presence or absence of Tregs, or after blocking of either IL-10 or IL-10R1. Results: The frequencies of CD4⁺CD25^high and CD4⁺CD25⁺CD127⁻ Tregs were significantly decreased immediately upon admission of TP to the ED and during the following 10 post-injury days. Compared with HV CD4⁺ T cell proliferation in TP increased significantly upon their admission and on the following days. As expected, CD4⁺CD25⁺CD127⁻ Tregs reduced the proliferation of CD4⁺ cells in HV, nevertheless, CD4⁺ proliferation in TP was increased by Tregs. Neutralization of IL-10 as well as blocking the IL-10R1 increased further CD4⁺ T cell proliferation in Tregs-depleted cultures, thereby confirming an IL-10-mediated mechanism of IL-10-regulated CD4⁺ T cell proliferation. Neutralization of IL-10 in TP decreased CD4⁺ T cell proliferation in Tregs-depleted cultures, whereas blocking of the IL-10R1 receptor had no significant effects. Conclusions: The frequency of Tregs in the CD4⁺ T lymphocyte population is reduced after trauma; however, their inductiveness is increased. The mechanisms of deregulated influence of Tregs on CD4⁺ T cell proliferation are mediated via IL-10 but not via the IL-10R1.

Outcomes after pneumonectomy versus limited lung resection in adults with traumatic lung injury

Pneumonectomy after traumatic lung injury (TLI) is associated with shock, increased pulmonary vascular resistance, and eventual right ventricular failure. Historically, trauma pneumonectomy (TP) mortality rates ranged between 53 and 100%. It is unclear if contemporary mortality rates have improved. Therefore, we evaluated outcomes associated with TP and limited lung resections (LLR) (i.e., lobectomy and segmentectomy) and aimed to identify predictors of mortality, hypothesizing that TP is associated with greater mortality versus LLR. We queried the Trauma Quality Improvement Program (2010–2016) and performed a multivariable logistic regression to determine the independent predictors of mortality in TLI patients undergoing TP versus LLR. TLI occurred in 287,276 patients. Of these, 889 required lung resection with 758 (85.3%) undergoing LLR and 131 (14.7%) undergoing TP. Patients undergoing TP had a higher median injury severity score (26.0 vs. 24.5, p = 0.03) but no difference in initial median systolic blood pressure (109 vs. 107 mmHg, p = 0.92) compared to LLR. Mortality was significantly higher for TP compared to LLR (64.9% vs 27.2%, p < 0.001). The strongest independent predictor for mortality was undergoing TP versus LLR (OR 4.89, CI 3.18–7.54, p < 0.001). TP continues to be associated with a higher mortality compared to LLR. Furthermore, TP is independently associated with a fivefold increased risk of mortality compared to LLR. Future investigations should focus on identifying parameters or treatment modalities that improve survivability after TP. We recommend that surgeons reserve TP as a last-resort management given the continued high morbidity and mortality associated with this procedure.

Injury-related variation in patient-reported outcome after musculoskeletal trauma: a systematic review

PURPOSE

The purpose of this study was to explore injury-related characteristics that differentiate between patient-reported outcomes (PROs) following traumatic musculoskeletal injury.

METHODS

We reviewed English-language articles in PubMed/MEDLINE, Google Scholar, and the Cochrane Database of Systematic Reviews (January 1995 to September 2018). We included studies that compared patient-reported outcomes of musculoskeletal trauma based on injury characteristics, and excluded studies related to development or validation of outcome tools without implementation, measurement, or comparison. Studies on patients with isolated neurotrauma or spine trauma were not included. Study level of evidence was assessed by 2 reviewers using the modified Oxford Centre for Evidence-based Medicine rating system.

RESULTS

A total of 20 studies (21 articles) that reported on a total of 10,186 patients were included (4 were prospective cohort-studies, 8 were matched-control retrospective cohort-studies, and 8 were retrospective cohort-studies). Median minimum follow-up was 3 years (range 0.5-10 years). Injury-related factors associated with worse PROs were polytrauma or multiple injuries (10 studies), neurotrauma (11 studies), and high-energy injury mechanism (7 studies). Among all studies, 32 different outcome metrics were used (17 general health status metrics and 15 limb-specific metrics) making meta-analysis infeasible.

CONCLUSIONS

Based on the included studies, we propose a framework where musculoskeletal injuries occur in one of 4 scenarios that is associated with a different context-dependent outcome: (1) polytrauma with neurotrauma, (2) polytrauma without neurotrauma, (3) high-energy monotrauma, and (4) low-energy monotrauma. Our results suggest that standardization of outcome instruments is needed to facilitate future meta-analyses that assess PROs in this population.

Microcirculatory Impairment Is Associated With Multiple Organ Dysfunction Following Traumatic Hemorrhagic Shock: The MICROSHOCK Study

OBJECTIVES

To assess the relationship between microcirculatory perfusion and multiple organ dysfunction syndrome in patients following traumatic hemorrhagic shock.

DESIGN

Multicenter prospective longitudinal observational study.

SETTING

Three U.K. major trauma centers.

PATIENTS

Fifty-eight intubated and ventilated patients with traumatic hemorrhagic shock.

INTERVENTIONS

Sublingual incident dark field microscopy was performed within 12 hours of ICU admission (D0) and repeated 24 and 48 hours later. Cardiac output was assessed using oesophageal Doppler. Multiple organ dysfunction syndrome was defined as Serial Organ Failure Assessment score greater than or equal to 6 at day 7 post injury.

MEASUREMENTS AND MAIN RESULTS

Data from 58 patients were analyzed. Patients had a mean age of 43 ± 19 years, Injury Severity Score of 29 ± 14, and initial lactate of 7.3 ± 6.1 mmol/L and received 6 U (interquartile range, 4-11 U) of packed RBCs during initial resuscitation. Compared with patients without multiple organ dysfunction syndrome at day 7, patients with multiple organ dysfunction syndrome had lower D0 perfused vessel density (11.2 ± 1.8 and 8.6 ± 1.8 mm/mm; p < 0.01) and microcirculatory flow index (2.8 [2.6-2.9] and 2.6 [2.2-2.8]; p < 0.01) but similar cardiac index (2.5 [± 0.6] and 2.1 [± 0.7] L/min//m; p = 0.11). Perfused vessel density demonstrated the best discrimination for predicting subsequent multiple organ dysfunction syndrome (area under curve 0.87 [0.76-0.99]) compared with highest recorded lactate (area under curve 0.69 [0.53-0.84]), cardiac index (area under curve 0.66 [0.49-0.83]) and lowest recorded systolic blood pressure (area under curve 0.54 [0.39-0.70]).

CONCLUSIONS

Microcirculatory hypoperfusion immediately following traumatic hemorrhagic shock and resuscitation is associated with increased multiple organ dysfunction syndrome. Microcirculatory variables are better prognostic indicators for the development of multiple organ dysfunction syndrome than more traditional indices. Microcirculatory perfusion is a potential endpoint of resuscitation following traumatic hemorrhagic shock.

Modeling trauma in rats: similarities to humans and potential pitfalls to consider

Trauma is the leading cause of mortality in humans below the age of 40. Patients injured by accidents frequently suffer severe multiple trauma, which is life-threatening and leads to death in many cases. In multiply injured patients, thoracic trauma constitutes the third most common cause of mortality after abdominal injury and head trauma. Furthermore, 40-50% of all trauma-related deaths within the first 48 h after hospital admission result from uncontrolled hemorrhage. Physical trauma and hemorrhage are frequently associated with complex pathophysiological and immunological responses. To develop a greater understanding of the mechanisms of single and/or multiple trauma, reliable and reproducible animal models, fulfilling the ethical 3 R's criteria (Replacement, Reduction and Refinement), established by Russell and Burch in 'The Principles of Human Experimental Technique' (published 1959), are required. These should reflect both the complex pathophysiological and the immunological alterations induced by trauma, with the objective to translate the findings to the human situation, providing new clinical treatment approaches for patients affected by severe trauma. Small animal models are the most frequently used in trauma research. Rattus norvegicus was the first mammalian species domesticated for scientific research, dating back to 1830. To date, there exist numerous well-established procedures to mimic different forms of injury patterns in rats, animals that are uncomplicated in handling and housing. Nevertheless, there are some physiological and genetic differences between humans and rats, which should be carefully considered when rats are chosen as a model organism. The aim of this review is to illustrate the advantages as well as the disadvantages of rat models, which should be considered in trauma research when selecting an appropriate in vivo model. Being the most common and important models in trauma research, this review focuses on hemorrhagic shock, blunt chest trauma, bone fracture, skin and soft-tissue trauma, burns, traumatic brain injury and polytrauma.

Impact of Accidental Hypothermia on Pulmonary Complications in Multiply Injured Patients With Blunt Chest Trauma - A Matched-pair Analysis

BACKGROUND/AIM

Blunt chest trauma is one of the major injuries in multiply injured patients and is associated with an increased risk of acute respiratory distress syndrome (ARDS) and ventilator-associated pneumonia (VAP). Accidental hypothermia is a common accompaniment of multiply injured patients. The objective of this study was to analyze the influence of accidental hypothermia on pulmonary complications in multiply injured patients with blunt chest trauma.

PATIENTS AND METHODS

Multiply injured patients [injury severity score (ISS) ≥16] with severe blunt chest trauma [abbreviated injury scale of the chest (AISchest) ≥3] were analyzed. Hypothermia was defined as body core temperature <35°C. The primary endpoint was the development of ARDS and VAP. Propensity score matching was performed.

RESULTS

Data were analyzed for 238 patients, with a median ISS of 26 (interquartile range=12). A total of 67 patients (28%) were hypothermic on admission. Hypothermic patients were injured more severely (median ISS 34 vs. 24, p<0.001) and had a higher transfusion requirement (p<0.001). Their mortality rate was consequently increased (10% vs. 1%, p=0.002); After propensity score matching, the mortality rate was still higher (10% vs. 2%, p=0.046). However, hypothermia was not an independent predictor of mortality. Hypothermic patients had to be ventilated longer (p=0.02). However, there were no differences in occurrence of ARDS and VAP. Hypothermia was not identified as an independent predictor of ARDS and VAP.

CONCLUSION

Among multiply injured patients with severe blunt chest trauma, accidental hypothermia is not an independent predictor of ARDS and VAP and is more likely to be an accompaniment of injury severity and hemorrhage.

The Importance of Sex Differences on Outcome after Major Trauma: Clinical Outcome in Women Versus Men

Purpose: The purpose of this study was to evaluate epidemiological and clinically relevant sex-related differences in polytraumatized patients at a Level 1 Trauma Center. Methods: 646 adult patients (210 females and 436 males) who were classified as polytraumatized (at the point of admission) and treated at our Level I Trauma Center were reviewed and included in this study. Demographic data as well as mechanism of injury, injury severity, injury pattern, frequency of preclinical intubation, hemodynamic variables on admission, time of mechanical ventilation and of intensive care unit (ICU) treatment, as well as the incidence of acute respiratory distress syndrome (ARDS), multi organ failure (MOF), and mortality were extracted and analyzed. Results: A total of 210 female and 436 male patients formed the basis of this report. Females showed a higher mean age (44.6 vs. 38.3 years; p < 0.0001) than their male counterparts. Women were more likely to be injured as passengers or by suicidal falls whereas men were more likely to suffer trauma as motorcyclists. Following ICU treatment, female patients resided significantly longer at the casualty ward than men (27.1 days vs. 20.4 days, p = 0.013) although there was no significant difference regarding injury severity, hemodynamic variables on admission, and incidence of MOF, ARDS, and mortality. Conclusion: The positive correlation of higher age and longer in-hospital stay in female trauma victims seems to show women at risk for a prolonged in-hospital rehabilitation time. A better understanding of the impact of major trauma in women (but also men) will be an important component of efforts to improve trauma care and long-term outcome.

Traumatic injury pattern is of equal relevance as injury severity for experimental (poly)trauma modeling

This study aims to elaborate the relevance of trauma severity and traumatic injury pattern in different multiple and/or polytrauma models by comparing five singular trauma to two different polytrauma (PT) models with high and one multiple trauma (MT) model with low injury-severity score (ISS). The aim is to provide a baseline for reducing animal harm according to 3Rs by providing less injury as possible in polytrauma modeling. Mice were randomly assigned to 10 groups: controls (Ctrl; n = 15), Sham (n = 15); monotrauma groups: hemorrhagic shock (HS; n = 15), thoracic trauma (TxT; n = 18), osteotomy with external fixation (Fx; n = 16), bilateral soft tissue trauma (bSTT; n = 16) or laparotomy (Lap; n = 16); two PT groups: PT I (TxT + HS + Fx; ISS = 18; n = 18), PT II (TxT + HS + Fx + Lap; ISS = 22; n = 18), and a MT group (TxT + HS + bSTT + Lap, ISS = 13; n = 18). Activity and mortality were assessed. Blood gas analyses and organ damage markers were determined after 6 h. Significant mortality occurred in TxT, PT and MT (11.7%). Activity decreased significantly in TxT, HS, both polytrauma and MT vs. Ctrl/Sham. PT-groups and MT had significantly decreased activity vs. bsTT, Lap or Fx. MT had significantly lower pCO₂vs. Ctrl/Sham, Lap or bsTT. Transaminases increased significantly in PT-groups and MT vs. Ctrl, Sham or monotrauma. Traumatic injury pattern is of comparable relevance as injury severity for experimental multiple or (poly)trauma modeling.

Feature Selection for Longitudinal Data by Using Sign Averages to Summarize Gene Expression Values over Time

With the rapid evolution of high-throughput technologies, time series/longitudinal high-throughput experiments have become possible and affordable. However, the development of statistical methods dealing with gene expression profiles across time points has not kept up with the explosion of such data. The feature selection process is of critical importance for longitudinal microarray data. In this study, we proposed aggregating a gene's expression values across time into a single value using the sign average method, thereby degrading a longitudinal feature selection process into a classic one. Regularized logistic regression models with pseudogenes (i.e., the sign average of genes across time as predictors) were then optimized by either the coordinate descent method or the threshold gradient descent regularization method. By applying the proposed methods to simulated data and a traumatic injury dataset, we have demonstrated that the proposed methods, especially for the combination of sign average and threshold gradient descent regularization, outperform other competitive algorithms. To conclude, the proposed methods are highly recommended for studies with the objective of carrying out feature selection for longitudinal gene expression data.

Changes in the temporal distribution of in-hospital mortality in severely injured patients-An analysis of the TraumaRegister DGU

Background

The temporal distribution of trauma mortality has been classically described as a trimodal pattern with an immediate, early and late peak. In modern health care systems this time distribution has changed.

Methods

Data from the TraumaRegister DGU was analysed retrospectively. Between 2002 and 2015, all registered in-hospital deaths with an Injury Severity Score (ISS) ≥ 16 were evaluated considering time of death, trauma mechanism, injured body area, age distribution, rates of sepsis and multiple organ failure. Pre-hospital and post-discharge trauma deaths were not considered.

Results

78 310 severely injured patients were registered, non-survivors constituted 14 816, representing an in-hospital mortality rate of 18.9%. Mean ISS of non-survivors was 36.0±16.0, 66.7% were male, mean age was 59.5±23.5. Within the first hour after admission to hospital, 10.8% of deaths occurred, after 6 hours the percentage increased to 25.5%, after 12 hours 40.0%, after 24 hours 53.2% and within the first 48 hours 61.9%. Mortality showed a constant temporal decrease. Severe head injury (defined by Abbreviated Injury Scale, AIS-Head≥3) was found in 76.4% of non-survivors. Patients with an isolated head injury showed a more distinct decrease in survival rate, which was accentuated in the first days after admission. The correlation of age and time of death showed a proportional increase with age (55-74a). The rate of sepsis and multiple organ failure among non-survivors was 11.5% and 70.1%, respectively.

Conclusion

In a modern trauma care system, the mortality distribution of severely injured patients has changed its pattern, where especially the third peak is no longer detectable.

A Concomitant Muscle Injury Does Not Worsen Traumatic Brain Injury Outcomes in Mice

Traumatic brain injury (TBI) often involves multitrauma in which concurrent extracranial injury occurs. We previously demonstrated that a long bone fracture exacerbates neuroinflammation and functional outcomes in mice given a TBI. Whether other forms of concomitant peripheral trauma that are common in the TBI setting, such as skeletal muscle injury, have similar effects is unknown. As such, here we developed a novel mouse multitrauma model by combining a closed-skull TBI with a cardiotoxin (CTX)-induced muscle injury to investigate whether muscle injury affects TBI outcomes. Adult male mice were assigned to four groups: sham-TBI + sham-muscle injury (SHAM); sham-TBI + CTX-muscle injury (CTX); TBI + sham-muscle injury (TBI); TBI + CTX-muscle injury (MULTI). Some mice were euthanized at 24 h post-injury to assess neuroinflammation and cerebral edema. The remaining mice underwent behavioral testing after a 30-day recovery period, and were euthanized at 35 days post-injury for post-mortem analysis. At 24 h post-injury, both TBI and MULTI mice had elevated edema, increased expression of GFAP (i.e., a marker for reactive astrocytes), and increased mRNA levels of inflammatory chemokines. There was also an effect of injury on cytokine levels at 35 days post-injury. However, the TBI and MULTI mice did not significantly differ on any of the measures assessed. These initial findings suggest that a concomitant muscle injury does not significantly affect preclinical TBI outcomes. Future studies should investigate the combination of different injury models, additional outcomes, and other post-injury time points.

A longitudinal feature selection method identifies relevant genes to distinguish complicated injury and uncomplicated injury over time

BACKGROUND

Feature selection and gene set analysis are of increasing interest in the field of bioinformatics. While these two approaches have been developed for different purposes, we describe how some gene set analysis methods can be utilized to conduct feature selection.

METHODS

We adopted a gene set analysis method, the significance analysis of microarray gene set reduction (SAMGSR) algorithm, to carry out feature selection for longitudinal gene expression data.

RESULTS

Using a real-world application and simulated data, it is demonstrated that the proposed SAMGSR extension outperforms other relevant methods. In this study, we illustrate that a gene's expression profiles over time can be regarded as a gene set and then a suitable gene set analysis method can be utilized directly to select relevant genes associated with the phenotype of interest over time.

CONCLUSIONS

We believe this work will motivate more research to bridge feature selection and gene set analysis, with the development of novel algorithms capable of carrying out feature selection for longitudinal gene expression data.

The impact of non-thermal injuries in combined burn trauma: A retrospective analysis over the past 35 years

INTRODUCTION

Combined burn trauma is rather uncommon and frequently difficult to manage. Historically combined burn trauma contributed to high mortality rates in severely injured patients. The purpose of this study was to determine the incidence, mechanisms and impact of non-thermal injuries in patients with severe burns.

METHODS

The charts of 2536 patients admitted to the Burn Center of the University Hospital Zurich between 1977 and 2013 were reviewed and retrospectively analyzed. Patients with additional injuries were identified and analyzed statistically.

RESULTS

Over 35 years from 1977 to 2013 a total of 100 burn patients (3.9%) with additional trauma were identified. Motor vehicle crash was the most common mechanism of injury (44%) from 1977 to 1995, compared to electrical injury (33%) from 1996 to 2013. Skeletal trauma including spinal and pelvic injury was the most common form (71%). Additional thoracic or abdominal trauma represented the highest risk factor for in-hospital mortality (adjusted RR 2.2, 95% CI 0.6-7.6). However, after 1995 the presence of any form of additional injury did not have a significant impact on in-hospital mortality (unadjusted RR 0.97, 95% CI 0.5-1.7, p = 0.914).

CONCLUSIONS

Concomitant trauma did not reveal a significant impact on in-hospital mortality in our burn center recently. Retrospectively, trauma mechanisms shifted from motor vehicle crashes to electrical injuries in our population. Safety measures for motor vehicles and adequate emergency room algorithms seem to have contributed to a reduction of severity of injury and mortality.

Patient experiences of initial trauma care

BACKGROUND

Correct initial treatment of trauma patients reduces mortality and morbidity. However, the initial examination may be perceived as traumatic because of the stressful situation, the unfamiliar setting and the shock of being seriously injured. To date, little is known about patient's experiences of initial trauma management. The aim of this study was to explore trauma patients' experiences of being exposed to initial full trauma team assessment at a Level 1 trauma centre.

METHODS

Interviews with 16 patients who had been exposed to initial trauma care were conducted at a Level 1 trauma centre, at a Swedish University Hospital. The interviews were transcribed verbatim and analysed with qualitative content analysis.

RESULTS

Patients' experiences of initial trauma care can be summarized as: feeling safe in a frightening situation. The trauma team members were mostly perceived as professional, well-organised, and efficient. Yet, the patients described an emotional response to the trauma, physical discomfort during the examination, and feeling prioritised or being ignored in the encounter with the trauma team members.

CONCLUSION

The initial trauma care may be improved if the trauma team members keep the patient's physical and emotional wellbeing in focus and maintain an informative dialogue with the patient during the whole process.

Early immune response regulated by a bone marrow mesenchymal stem cell model of multiple trauma in rats

AIM

To explore whether transplantation of bone marrow mesenchymal stem cells (BMSCs) would reduce the immune response and protect vital organs in a rat model of femur shaft fracture combined with craniocerebral injury.

METHODS

The rats were divided into an experimental group (multiple traumas and receiving BMSCs injection, n = 25), a positive control group (only received the combination injuries, n = 25) and a negative group (n = 5).

RESULTS

Compared with the positive control group, plasma IL-6 and IL-8 were significantly lower at the early stage, and IL-10 was higher at the late period in the experimental group (p < 0.05). TNF-α ex-vivo synthesis descended quickly after trauma.

CONCLUSION

BMSCs reduced the inflammatory response and were effective in immunomodulations during severe trauma.

The use of extracorporeal membrane oxygenation in trauma patients: A national case-control study

Extracorporeal membrane oxygenation (ECMO) has been increasingly applied for the treatment of patients with trauma. Because a common complication of ECMO is bleeding, the use of ECMO support for patients with trauma was limited in the past. Studies have demonstrated a survival benefit from ECMO support in cases of traumatic lung injury, and it is likely that patients with other types of trauma would also benefit from ECMO support. However, the effect of ECMO in patients with other types of trauma is unknown.Using the national insurance data of Taiwan, we identified 810 patients with trauma who received ECMO support from 2000 to 2010. Patients who died or who withdrew from the program within 7 days after discharge were defined as deceased. Logistic regression was used to estimate the odds ratio (OR) of death and 95% confidence intervals (CIs).The overall mortality was 32.8% (266/810). A total of 417 patients received surgery during hospitalization, with an overall mortality of 39.0% (163/417). Patients who underwent thoracic surgery had an OR of 2.23 (95% CI: 1.49-3.34) compared with those who did not. Patients who underwent brain surgery had an OR of 2.86 (95% CI: 1.37-5.98) compared with patients who did not. Patients who received abdominal surgery had an OR of 4.47 (95% CI: 2.63-7.61) compared with patients who did not. All types of surgery had odds of mortality except orthopedic surgery; the use of ECMO with orthopedic surgery had an OR of 1.06 (95% CI: 0.69-1.62) compared with patients who did not receive orthopedic surgery.Except for orthopedic surgery, patients with trauma who received ECMO support and required further surgery during hospitalization exhibited a relatively high mortality rate.

To select relevant features for longitudinal gene expression data by extending a pathway analysis method

The emerging field of pathway-based feature selection that incorporates biological information conveyed by gene sets/pathways to guide the selection of relevant genes has become increasingly popular and widespread. In this study, we adapt a gene set analysis method - the significance analysis of microarray gene set reduction (SAMGSR) algorithm to carry out feature selection for longitudinal microarray data, and propose a pathway-based feature selection algorithm - the two-level SAMGSR method. By using simulated data and a real-world application, we demonstrate that a gene's expression profiles over time can be considered as a gene set. Thus a suitable gene set analysis method can be utilized or modified to execute the selection of relevant genes for longitudinal omics data. We believe this work paves the way for more research to bridge feature selection and gene set analysis with the development of novel pathway-based feature selection algorithms.

An overview of cytokines and heat shock response in polytraumatized patients

Early after injury, local tissue damage induces a local and systemic inflammatory response that activates the immune system and leads to the development of systemic inflammatory response syndrome (SIRS). This post-traumatic response often results in uncontrolled release of inflammatory mediators and over-activation of the immune system, which occasionally results in multiple organ dysfunction syndrome (MODS). In parallel, a state of immunosuppression develops. This counter-regulating suppression of different cellular and humoral immune functions has been termed "compensatory anti-inflammatory response syndrome (CARS)." Both SIRS and CARS occur simultaneously even in the initial phase after injury. Pro- and anti-inflammatory cytokines have been suggested to play a major role in development of SIRS, although the degree of involvement of the different cytokines is quite disparate. While TNF-α and IL-1β are quite irrelevant for predicting organ dysfunction, IL-6 is the parameter that best predicts mortality. The hyperinflammatory state seems to be the cause of post-traumatic immunosuppression and heat shock proteins (HSPs), which have been proposed as one of the endogenous stimuli for the deterioration of the immune system acting as danger-associated molecular patterns (DAMPs). Extracellular HSPA1A released from injured tissues increase up to ten times immediately after trauma and even more in patients with MODS. It has powerful immune properties that could contribute to post-traumatic immunosuppression through several mechanisms that have been previously described, so HSPs could represent trauma-associated immunomodulatory mediators. For this reason, HSPA1A has been suggested to be a helpful early prognostic biomarker of trauma after severe injury: serial quantification of serum HSPA1A and anti-Hsp70 concentrations in the first hours after trauma is proposed to be used as a predictive biomarker of MODS and immunosuppression development in polytraumatized patients.

Foot fractures in polytrauma patients: Injury characteristics and timing of diagnosis

BACKGROUND

Due to prioritizing care and concomitant injuries, foot fractures in polytrauma patients often receive limited attention initially. However, as foot function is important, treatment and diagnosis of these fractures should be accurate. The aims of this study were to assess the incidence and distribution of foot fractures in polytrauma patients and to examine possible risk factors for delayed diagnosis of foot fractures.

METHODS

This was a retrospective study on all adult (≥18 years) polytrauma (ISS ≥16) patients admitted to a single level 1 trauma center between 2006 and 2016. Patients with foot fractures were identified by diagnosis codes. Data on demographics and trauma characteristics were collected from the Trauma Quality Improvement Program (TQIP^®) database. Data on foot fractures were gathered from electronic patient documentation.

RESULTS

Out of 4409 polytrauma patients, 221 (5.0%) sustained a total of 511 foot fractures. Metatarsal fractures were most common (41%), followed by calcaneal (17%), and talar (16%) fractures. Thirty percent of the fractures in 33% of all patients were diagnosed in a delayed fashion. This had treatment consequences in 8%. Delayed diagnosed fractures were more common in older patients (p 0.025), patients with a higher ISS (p 0.012), ICU admission (p 0.015), and concomitant head injury (p 0.020).

CONCLUSIONS

As one in twenty polytrauma patients sustains at least one foot fracture and a substantial amount of these fractures are diagnosed in a delayed fashion, physicians, regardless of their specialty, should have a high index of suspicion for injuries of the feet in polytrauma patients.

Influence of Entrapment on Prehospital Management and the Hospital Course in Polytrauma Patients: A Retrospective Analysis in Air Rescue

BACKGROUND

Entrapment is a challenging and crucial factor in the prehospital setting. Few studies have addressed whether entrapment has an influence on on-scene treatment or on the following hospital course.

OBJECTIVES

Here we aimed to investigate the influence of entrapment on prehospital management and on the hospital course of polytrauma patients.

METHODS

We performed a retrospective analysis of consecutive patients with an Injury Severity Score ≥16 and aged 16-65 years that were admitted between 2005 and 2013 to a Level I trauma center. Two groups were built: entrapped (E) and nonentrapped patients (nE). These groups were evaluated for multiple prehospital and clinical parameters, including on-scene time, prehospital interventions, and posttraumatic complications.

RESULTS

There were 310 patients (n = 194 no entrapment [Group nE], n = 116 with entrapment [Group E]) enrolled. The on-scene time was significantly longer in Group E than Group nE. Moreover, this group received a significantly higher volume of colloidal solution. Regarding the Injury Severity Score and Abbreviated Injury Scale (AIS), there were no significant differences between the groups, except for the AIS_extremities, which was significantly increased in Group E. The overall hospital stay and the initial theater time were significantly longer in Group E than Group nE. No significant differences were present for the occurrence of systemic inflammatory response syndrome, multiple organ dysfunction syndrome, and acute respiratory distress syndrome, nor for Acute Physiology and Chronic Health Evaluation II and estimated and final mortality.

CONCLUSION

In polytraumatized patients, entrapment has a minor influence on the outcome and treatment in the prehospital and hospital setting when using physician-based air rescue. However, entrapped patients are prone to sustain more severe trauma to the extremities.

The influence of immunological stressors on traumatic brain injury

Traumatic brain injury (TBI) is a leading cause of death and disability worldwide, and typically involves a robust immune response. Although a great deal of preclinical research has been conducted to identify an effective treatment, all phase III clinical trials have been unsuccessful to date. These translational shortcomings are in part due to a failure to recognize and account for the heterogeneity of TBI, including how extracranial factors can influence the aftermath of TBI. For example, most preclinical studies have utilized isolated TBI models in young adult males, while clinical trials typically involve highly heterogeneous patient populations (e.g., different mechanisms of injury, a range of ages, presence of polytrauma or infection). This paper will review the current, albeit limited literature related to how TBI is affected by common concomitant immunological stressors. In particular, discussion will focus on whether extracranial trauma (i.e., polytrauma), infection, and age/immunosenescence can influence TBI pathophysiology, and thereby may result in a different brain injury than what would have occurred in an isolated TBI. It is concluded that these immunological stressors are all likely to be TBI modifiers that should be further studied and could impact translational treatment strategies.

A criteria-directed protocol for in-hospital triage of trauma patients

OBJECTIVE

To better match hospital resources to patients' needs of trauma care, a protocol for facilitating in-hospital triage decisions was implemented at a Swedish level I trauma centre. In the protocol, physiological parameters, anatomical injuries and mechanism of injury were documented, and used to activate full or limited trauma team response. The aim of this study was to evaluate the efficacy of the criteria-directed protocol to determine in-hospital trauma triage in an emergency department.

METHODS

Level of triage and triage rates were compared before and after implementation of the protocol. Overtriage and undertriage were assessed with injury severity score higher than 15 as the cutoff for defining major trauma. Medical records for undertriaged patients were retrospectively reviewed.

RESULTS

In 2011, 78% of 1408 trauma team activations required full trauma response, with an overtriage rate of 74% and an undertriage rate of 7%. In 2013, after protocol implementation, 58% of 1466 trauma team activations required full trauma response. Overtriage was reduced to 52% and undertriage was increased to 10%. However, there were no preventable deaths in the undertriaged patients.

CONCLUSION

A criteria-directed protocol for use in the emergency department was efficient in reducing overtriage rates without risking undertriaged patients' safety.

Injury mechanisms, patterns and outcomes of older polytrauma patients-An analysis of the Dutch Trauma Registry

Background

Polytrauma patients nowadays tend to be older due to the growth of the elderly population and its improved mobility. The aim of this study was to compare demographics, injury patterns, injury mechanisms and outcomes between younger and older polytrauma patients.

Methods

Data from polytrauma (ISS≥16) patients between 2009 and 2014 were extracted from the Dutch trauma registry (DTR). Younger (Group A: ages 18–59) and older (Group B: ages ≥60) polytrauma patients were compared. Differences in injury severity, trauma mechanism (only data for the year 2014), vital signs, injury patterns, ICU characteristics and hospital mortality were analyzed.

Results

Data of 25,304 polytrauma patients were analyzed. The older patients represented 47.8% of the polytrauma population. Trauma mechanism in the older patients was more likely to be a bicycle accident (A: 17%; B: 21%) or a low-energy fall (A: 13%; B: 43%). Younger polytrauma patients were more likely to have the worst scores on the Glasgow coma scale (EMV = 3, A: 20%, B: 13%). However, serious head injuries were seen more often in the older patients (A: 53%; B: 69%). The hospital mortality was doubled for the older polytrauma patients (19.8% vs. 9.6%).

Conclusion

Elderly are involved more often in polytrauma. Although injury severity did not differ between groups, the older polytrauma patients were at a higher risk of dying than their younger counterparts despite sustaining less high-energy accidents.

Mouse Injury Model of Polytrauma and Shock

Severe injury and shock remain major sources of morbidity and mortality worldwide. Immunologic dysregulation following trauma contributes to these poor outcomes. Few, if any, therapeutic interventions have benefited these patients, and this is due to our limited understanding of the host response to injury and shock. The Food and Drug Administration requires preclinical animal studies prior to any interventional trials in humans; thus, animal models of injury and shock will remain the mainstay for trauma research. However, adequate animal models that reflect the severe response to trauma in both the acute and subacute phases have been limited. Here we describe a novel murine model of polytrauma and shock that combines hemorrhagic shock, cecectomy, long bone fracture, and soft-tissue damage. This model produces an equivalent Injury Severity Score associated with adverse outcomes in humans, and may better recapitulate the human leukocyte, cytokine, transcriptomic, and overall inflammatory response following injury and hemorrhagic shock.

Development and pilot testing of an informed consent video for patients with limb trauma prior to debridement surgery using a modified Delphi technique

BACKGROUND

Ensuring adequate informed consent for surgery in a trauma setting is challenging. We developed and pilot tested an educational video containing information regarding the informed consent process for surgery in trauma patients and a knowledge measure instrument and evaluated whether the audiovisual presentation improved the patients' knowledge regarding their procedure and aftercare and their satisfaction with the informed consent process.

METHODS

A modified Delphi technique in which a panel of experts participated in successive rounds of shared scoring of items to forecast outcomes was applied to reach a consensus among the experts. The resulting consensus was used to develop the video content and questions for measuring the understanding of the informed consent for debridement surgery in limb trauma patients. The expert panel included experienced patients. The participants in this pilot study were enrolled as a convenience sample of adult trauma patients scheduled to receive surgery.

RESULTS

The modified Delphi technique comprised three rounds over a 4-month period. The items given higher scores by the experts in several categories were chosen for the subsequent rounds until consensus was reached. The experts reached a consensus on each item after the three-round process. The final knowledge measure comprising 10 questions was developed and validated. Thirty eligible trauma patients presenting to the Emergency Department (ED) were approached and completed the questionnaires in this pilot study. The participants exhibited significantly higher mean knowledge and satisfaction scores after watching the educational video than before watching the video.

CONCLUSIONS

Our process is promising for developing procedure-specific informed consent and audiovisual aids in medical and surgical specialties. The educational video was developed using a scientific method that integrated the opinions of different stakeholders, particularly patients. This video is a useful tool for improving the knowledge and satisfaction of trauma patients in the ED. The modified Delphi technique is an effective method for collecting experts' opinions and reaching a consensus on the content of educational materials for informed consent. Institutions should prioritize patient-centered health care and develop a structured informed consent process to improve the quality of care.

TRIAL REGISTRATION

The ClinicalTrials.gov Identifier is NCT01338480 . The date of registration was April 18, 2011 (retrospectively registered).

Frequency and perforin expression of different lymphocyte subpopulations in patients with lower limb fracture and thoracic injury

INTRODUCTION

Trauma with multiple injuries is associated with a high risk of complications, which may be related to excessive stimulation of inflammatory and anti-inflammatory responses. Although the effects of polytrauma on the immune response have been well established at the cellular and molecular levels, there is little information about the changes in the cytolytic potential of immunocompetent cells, including expression of cytotoxic molecules such as perforin. Therefore, the objective of the present study was to analyse and compare differences in the frequency and perforin expression of leukocyte subpopulations in the peripheral blood of patients with lower limb fracture, thoracic injury, and simultaneous lower limb fracture and thoracic injury.

PATIENTS AND METHODS

Forty-five patients with trauma injury (15 patients with lower limb injury, 15 patients with thoracic injury, and 15 patients with simultaneous lower limb and thoracic injury) were included in the study. Peripheral blood of 15 sex- and age-matched healthy volunteers served as the control group. Peripheral blood samples were taken from all subjects included in the study and peripheral blood mononuclear cells were isolated by gradient centrifugation. The frequency of T lymphocytes, natural killer (NK) and NK T cells, and their subsets, as well as their perforin expression levels were simultaneously detected and analysed by flow cytometry.

RESULTS

There was a statistically significant decrease in the frequency of T lymphocytes, NK and NK T cells as well as perforin expression in the patients with simultaneous lower limb and thoracic injury compared with the other two groups, with a predominantly marked decrease in NK and NK T cells.

CONCLUSION

The decrease in the frequency and cytotoxic potential of peripheral blood lymphocytes is related to the severity of trauma injury, which can explain the underlying mechanism contributing to complication occurrence.

Prediction of mortality risk in victims of violent crimes

BACKGROUND

To predict mortality risk in victims of violent crimes based on individual injury diagnoses and other information available in health care registries.

METHODS

Data from the Swedish hospital discharge registry and the cause of death registry were combined to identify 15,000 hospitalisations or prehospital deaths related to violent crimes. The ability of patient characteristics, injury type and severity, and cause of injury to predict death was modelled using conventional, Lasso, or Bayesian logistic regression in a development dataset and evaluated in a validation dataset.

RESULTS

Of 14,470 injury events severe enough to cause death or hospitalization 3.7% (556) died before hospital admission and 0.5% (71) during the hospital stay. The majority (76%) of hospital survivors had minor injury severity and most (67%) were discharged from hospital within 1day. A multivariable model with age, sex, the ICD-10 based injury severity score (ICISS), cause of injury, and major injury region provided predictions with very good discrimination (C-index=0.99) and calibration. Adding information on major injury interactions further improved model performance. Modeling individual injury diagnoses did not improve predictions over the combined ICISS score.

CONCLUSIONS

Mortality risk after violent crimes can be accurately estimated using administrative data. The use of Bayesian regression models provides meaningful risk assessment with more straightforward interpretation of uncertainty of the prediction, potentially also on the individual level. This can aid estimation of incidence trends over time and comparisons of outcome of violent crimes for injury surveillance and in forensic medicine.