Abbreviated Injury Scale: not a reliable basis for summation of injury severity in trauma facilities?

Machine learning models predict triage levels, massive transfusion protocol activation, and mortality in trauma utilizing patients hemodynamics on admission

BACKGROUND

The effective management of trauma patients necessitates efficient triaging, timely activation of Massive Blood Transfusion Protocols (MTP), and accurate prediction of in-hospital outcomes. Machine learning (ML) algorithms have emerged as up-and-coming tools in the domains of optimizing triage decisions, improving intervention strategies, and predicting clinical outcomes, consistently outperforming traditional methodologies. This study aimed to develop, assess, and compare several ML models for the triaging processes, activation of MTP, and mortality prediction.

METHODS

In a 10-year retrospective study, the predictive capabilities of seven ML models for trauma patients were systematically assessed using on-admission patients' hemodynamic data. All patient's data were randomly divided into training (80 %) and test (20 %) sets. Employing Python for data preprocessing, feature scaling, and model development, we evaluated K-Nearest Neighbors (KNN), Logistic Regression (LR), Decision Tree (DT), Support Vector Machines (SVM) with RBF kernels, Random Forest (RF), Extreme Gradient Boosting (XGBoost), and Artificial Neural Network (ANN). We employed various imputation techniques and addressed data imbalance through down-sampling, up-sampling, and synthetic minority for the over-sampling technique (SMOTE). Hyperparameter tuning, coupled with 5-fold cross-validation, was performed. The evaluation included essential metrics like sensitivity, specificity, F1 score, accuracy, Area Under the Receiver Operating Curve (AUC ROC), and Area Under the Precision recall Curve (AUC PR), ensuring robust predictive capability.

RESULT

This study included 17,390 adult trauma patients; of them, 19.5 % (3385) were triaged at a critical level, 3.8 % (664) required MTP, and 7.7 % (1335) died in the hospital. The model's performance improved using imputation and balancing techniques. The overall models demonstrated notable performance metrics for predicting triage, MTP activation, and mortality with F1 scores of 0.75, 0.42, and 0.79, sensitivities of 0.73, 0.82, and 0.9, and AUC ROC values of 0.89, 0.95 and 0.99 respectively.

CONCLUSION

Machine learning, especially RF models, effectively predicted trauma triage, MTP activation, and mortality. Featured critical hemodynamic variables include shock indices, systolic blood pressure, and mean arterial pressure. Therefore, models can do better than individual parameters for the early management and disposition of patients in the ED. Future research should focus on creating sensitive and interpretable models to enhance trauma care.

Missing patient registrations in the Dutch National Trauma Registry of Southwest Netherlands: Prevalence and epidemiology

INTRODUCTION

Health care patient records have been digitalised the past twenty years, and registries have been automated. Missing registrations are common, and can result in selection bias.

OBJECTIVE

To assess the prevalence and characteristics of missed registrations in a Dutch regional trauma registry.

METHODS

An automatically generated trauma registry export was done for ten out of eleven hospitals in trauma region Southwest Netherlands, between June 1 and August 31, 2020. Second, lists were checked for being falsely flagged as 'non-trauma'. Finally, a list was generated with trauma tick box flagged as 'trauma' but were not automatically in the export due to administrative errors. Automated and missed registration datasets were compared on patient characteristics and logistic regression models were run with random intercepts and missed registration as outcome variable on the complete dataset.

RESULTS

A total of 2,230 automated registrations and 175 (7.3 %) missed registrations were included for the Dutch National Trauma Registry, ranging from 1 to 14 % between participating hospitals. Patients of the missed registration dataset had characteristics of a higher level of care, compared with patients of automated registrations. Level of trauma care (level II OR 0.464 95 % CI 0.328-0.666, p < 0.001; level III OR 0.179 95 % CI 0.092-0.325, p < 0.001), major trauma (OR 2.928 95 % CI 1.792-4.65, p < 0.001), ICU admission (OR 2.337 95 % CI 1.792-4.650, p < 0.001), and surgery (OR 1.871 95 % CI 1.371-2.570, p < 0.001) were potential predictors for missed registrations in multivariate logistic regression analysis.

CONCLUSION

Missed registrations occur frequently and the rate of missed registrations differs greatly between hospitals. Automated and missed registration datasets display differences related to patients requiring more intensive care, which held for the major trauma subset. Checking for missed registrations is time consuming, automated registration lists need a human touch for validation and to be complete.

Health-related quality of life and return to work 1 year after major trauma from a network perspective

Introduction

Major trauma often results in long-term disabilities. The aim of this study was to assess health-related quality of life, cognition, and return to work 1 year after major trauma from a trauma network perspective.

Methods

All major trauma patients in 2016 (Injury Severity Score > 15, n = 536) were selected from trauma region Southwest Netherlands. Eligible patients (n = 365) were sent questionnaires with the EQ-5D-5L and questions on cognition, level of education, comorbidities, and resumption of paid work 1 year after trauma.

Results

A 50% (n = 182) response rate was obtained. EQ-US and EQ-VAS scored a median (IQR) of 0.81 (0.62–0.89) and 70 (60–80), respectively. Limitations were prevalent in all health dimensions of the EQ-5D-5L; 90 (50%) responders reported problems with mobility, 36 (20%) responders reported problems with self-care, 108 (61%) responders reported problems during daily activities, 129 (73%) responders reported pain or discomfort, 70 (39%) responders reported problems with anxiety or depression, and 102 (61%) of the patients reported problems with cognition. Return to work rate was 68% (37% full, 31% partial). A median (IQR) EQ-US of 0.89 (0.82–1.00) and EQ-VAS of 80 (70–90) were scored for fully working responders; 0.77 (0.66–0.85, p < 0.001) and 70 (62–80, p = 0.001) for partial working respondents; and 0.49 (0.23–0.69, p < 0.001) and 55 (40–72, p < 0.001) for unemployed respondents.

Conclusion

The majority experience problems in all health domains of the EQ-5D-5L and cognition. Return to work status was associated with all health domains of the EQ-5D-5L and cognition.

Accuracy of injury coding in a trauma registry

Introduction

Abbreviated Injury Scale has significant advantages over administrative coding systems for trauma analytics as it was developed specifically for injury, provides greater depth of characterisation of injury and has an integrated severity measure. It is used by trauma registries globally as it allows benchmarking between registries and is used to drive quality improvement. However, the consistency of scoring between individuals is not well understood. An audit was undertaken in six tertiary trauma centres in New Zealand to determine variation between AIS coders.

Methods

Each of six sites was audited by two experienced auditors. A random selection of case was identified in ISS categories 13–24, 25–44 and 45+. The case notes were pulled, and the auditors independently audited the notes,and then compared their results for a consensus result. The consensus result was then compared with the original coders.

Results

111 cases were audited. Coding concordance was found in 31% of cases. Of the 69% of cases where discordant coding was observed, the discordance was attributed to incorrect coding (49%), missed injuries (43%) and other reasons (7%). Head and chest body regions were associated with the greatest number, and largest differences in coding scores. The overall mean difference across all cases was an ISS score of 1.

Conclusions

The overall accuracy of data held in the New Zealand Trauma Registry (NZTR) is suitable for quality improvement and benchmarking purposes, but more work is needed to improve the accuracy of individual cases, particularly those with head/neck and chest injury. Standardised tools to ensure the accuracy of data in a trauma registry is a gap which needs to be addressed to maintain confidence in a contemporary trauma system.

New concept: "TARN friendly trauma reporting" (what radiologists say really does matter)

AIM

To establish if detailed review of trauma reports with reference to coding manual improved accuracy of ISS and to establish if demonstrated changes in coding affected performance and tariff payment.

MATERIALS AND METHODS

A study was undertaken which gathered data from 6 months across the five trusts with information on imaging undertaken, mechanism of injury (MOI), Injury Severity Score (ISS), and injury descriptors was included. Patients with ISS near to a best practice tariff boundary of 9 and 16 (5-8 and 11-15) then had their imaging reviewed by the Radiology Department with direct reference to the ISS coding manual. Injuries were then re-coded and ISS recalculated.

RESULTS

Over the 6-month period, 1,693 patients were admitted to the database from the five hospitals. One hundred and sixty-nine (9.9%) patients met the inclusion criteria for review. Thirty-five (20.7%) had a change in abbreviated (region specific) injury code, with 30 a change in the resultant ISS. Three had a decrease in ISS and 27 increased ISS with all 27 moving across an ISS best practice tariff and three moving across two payment tariff boundaries. With re-coding, there was a potential £15,000 of lost revenue from the major trauma centre (MTC) alone.

CONCLUSION

Reporting with reference to ISS description improves the accuracy of ISS significantly. Radiologists improving the descriptions of specific injury patterns and adopting 'Trauma Audit and Research Network friendly' reporting strategies may improve data accuracy, performance, and payment of best practice tariffs to hospitals.

RISC II is superior to TRISS in predicting 30-day mortality in blunt major trauma patients in Hong Kong

PURPOSE

Hong Kong (HK) trauma registries have been using the Trauma and Injury Severity Score (TRISS) for audit and benchmarking since their introduction in 2000. We compare the mortality prediction model using TRISS and Revised Injury Severity Classification, version II (RISC II) for trauma centre patients in HK.

METHODS

This was a retrospective cohort study with all five trauma centres in HK. Adult trauma patients with Injury Severity Score (ISS) > 15 suffering from blunt injuries from January 2013 to December 2015 were included. TRISS models using the US and local coefficients were compared with the RISC II model. The primary outcome was 30-day mortality and the area under the receiver operating characteristic curve (AUC) for tested models.

RESULTS

1840 patients were included, of whom 1236/1840 (67%) were male. Median age was 59 years and median ISS was 25. Low falls were the most common mechanism of injury. The 30-day mortality was 23%. RISC II yielded a superior AUC of 0.896, compared with the TRISS models (MTOS: 0.848; PATOS: 0.839; HK: 0.858). Prespecified subgroup analyses showed that all the models performed worse for age ≥ 70, ASA ≥ III, and low falls. RISC II had a higher AUC compared with the TRISS models in all subgroups, although not statistically significant.

CONCLUSION

RISC II was superior to TRISS in predicting the 30-day mortality for Hong Kong adult blunt major trauma patients. RISC II may be useful when performing future audit or benchmarking exercises for trauma in Hong Kong.

Interobserver variability of injury severity assessment in polytrauma patients: does the anatomical region play a role?

BACKGROUND

The Abbreviated Injury Scale (AIS) and Injury Severity Score (ISS) are widely used to assess trauma patients. In this study, the interobserver variability of the injury severity assessment for severely injured patients was analyzed based on different injured anatomical regions, and the various demographic backgrounds of the observers.

METHODS

A standardized questionnaire was presented to surgical experts and participants of clinical polytrauma courses. It contained medical information and initial X-rays/CT-scans of 10 cases of severely injured patients. Participants estimated the severity of each injury based on the AIS. Interobserver variability for the AIS, ISS, and New Injury Severity Score (NISS) was calculated by employing the statistical method of Krippendorff's α coefficient.

RESULTS

Overall, 54 participants were included. The major contributing medical specialties were orthopedic trauma surgery (N = 36, 67%) and general surgery (N = 13, 24%). The measured interobserver variability in the assessment of the overall injury severity was high (α ISS: 0.33 / α NISS: 0.23). Moreover, there were differences in the interobserver variability of the maximum AIS (MAIS) depending on the anatomical region: αhead and neck: 0.06, αthorax: 0.45, αabdomen: 0.27 and αextremities: 0.55.

CONCLUSIONS

Interobserver agreement concerning injury severity assessment appears to be low among clinicians. We also noted marked differences in variability according to injury anatomy. The study shows that the assessment of injury severity is also highly variable between experts in the field. This implies the need for appropriate education to improve the accuracy of trauma evaluation in the respective trauma registries.

Accuracy and reliability of injury coding in the national Dutch Trauma Registry

OBJECTIVE

Injury coding is well known for lack of completeness and accuracy. The objective of this study was to perform a nationwide assessment of accuracy and reliability on Abbreviated Injury Scale (AIS) coding by Dutch Trauma Registry (DTR) coders and to determine the effect on Injury Severity Score (ISS). Additionally, the coders' characteristics were surveyed.

METHODS

Three fictional trauma cases were presented to all Dutch trauma coders in a nationwide survey (response rate 69%). The coders were asked to extract and code the cases' injuries according to the AIS manual (version 2005, update 2008). Reference standard was set by three highly experienced coders. Summary statistics were used to describe the registered AIS codes and ISS distribution. The primary outcome measures were accuracy of injury coding and inter-rater agreement on AIS codes. Secondary outcome measures were characteristics of coders: profession, work setting, experience in injury coding and training level in injury coding.

RESULTS

The total number of different AIS codes used to describe 14 separate injuries in the three cases was 89. Mean accuracy per AIS code was 42.2% (range 2.4-92.7%). Mean accuracy on number of AIS codes was 23%. Overall inter-rater agreement per AIS code was 49.1% (range 2.4-92.7%). The number of assigned AIS codes varied between 0 and 18 per injury. Twenty-seven percentage of injuries were overlooked. ISS was correctly scored in 42.4%. In 31.7%, the AIS coding of the two more complex cases led to incorrect classification of the patient as ISS < 16 or ISS ≥ 16. Half (47%) of the coders had no (para)medical degree, 26% were working in level I trauma centers, 37% had less than 2 years of experience and 40% had no training in AIS coding.

CONCLUSIONS

Accuracy of and inter-rater agreement on AIS injury scoring by DTR coders is limited. This may in part be due to the heterogeneous backgrounds and training levels of the coders. As a result of the inconsistent coding, the number of major trauma patients in the DTR may be over- or underestimated. Conclusions based on DTR data should therefore be drawn with caution.

The impact of regionalized trauma care on the distribution of severely injured patients in the Netherlands

Background

Twenty years ago, an inclusive trauma system was implemented in the Netherlands. The goal of this study was to evaluate the impact of structured trauma care on the concentration of severely injured patients over time.

Methods

All severely injured patients (Injury Severity Score [ISS] ≥ 16) documented in the Dutch Trauma Registry (DTR) in the calendar period 2008–2018 were included for analysis. We compared severely injured patients, with and without severe neurotrauma, directly brought to trauma centers (TC) and non-trauma centers (NTC). The proportion of patients being directly transported to a trauma center was determined, as was the total Abbreviated Injury Score (AIS), and ISS.

Results

The documented number of severely injured patients increased from 2350 in 2008 to 4694 in 2018. During this period, on average, 70% of these patients were directly admitted to a TC (range 63–74%). Patients without severe neurotrauma had a lower chance of being brought to a TC compared to those with severe neurotrauma. Patients directly presented to a TC were more severely injured, reflected by a higher total AIS and ISS, than those directly transported to a NTC.

Conclusion

Since the introduction of a well-organized trauma system in the Netherlands, trauma care has become progressively centralized, with more severely injured patients being directly presented to a TC. However, still 30% of these patients is initially brought to a NTC. Future research should focus on improving pre-hospital triage to facilitate swift transfer of the right patient to the right hospital.

The AdHOC (age, head injury, oxygenation, circulation) score: a simple assessment tool for early assessment of severely injured patients with major fractures

Purpose

We sought to develop a simple, effective and accurate assessment tool using well-known prognostic parameters to predict mortality and morbidity in severely injured patients with major fractures at the stage of the trauma bay.

Methods

European Data from the TraumaRegister DGU^® were queried for patients aged 16 or older and with an ISS of 9 and higher with major fractures. The development (2012–2015) and validation (2016) groups were separated. The four prognostic aspects Age, Head injury, Oxygenation and Circulation along with parameters were identified as having a relevant impact on the outcome of severely injured patients with major fractures. The performance of the score was analyzed with the area under the receiver operating characteristics curve and compared to other trauma scores.

Results

An increasing AdHOC (Age, Head injury, Oxygenation, Circulation) score value in the 17,827 included patients correlated with increasing mortality (0 points = 0.3%, 1 point = 5.3%, 2 points = 15.6%, 3 points = 42.5% and 4 points = 62.6%). With an AUROC of 0.858 for the development (n = 14,047) and 0.877 for the validation (n = 3780) group dataset, the score is superior in performance compared to the Injury Severity Score (0.806/0.815).

Conclusion

The AdHOC score appears to be easy and accessible in every emergency room without the requirement of special diagnostic tools or knowledge of the exact injury pattern and can be useful for the planning of further surgical treatment.

Obesity is associated with a reduced odds for blunt intra-abdominal injuries in children

OBJECTIVES

Children with obesity may possess unique injury characteristics that may affect their emergency care. To better understand this relationship, we investigated the association of obesity in pediatric trauma patients and intra-abdominal injuries (IAIs) and routinely utilized emergency department (ED) diagnostic procedures (computed tomography (CT) scans and ultrasound (US) examinations).

METHODS

This secondary data analysis utilized Pediatric Emergency Care Applied Research Network (PECARN) data from 2007 to 2010. Since height data were not available, children (2-17 years) with obesity were defined using weight-for-age percentiles. Non-parametric testing determined potential confounders. Adjusted odds ratios (aOR) were calculated using binary logistic regression for weight status and IAIs and diagnostic procedures.

RESULTS

There were 3846 patients with actual weight recorded: 3301 (85.8%) children without obesity and 545 (14.2%) with obesity. Children with obesity had decreased odds for IAI after adjusting for race, mechanical force injury (MFI) type, vomiting, and abdominal wall trauma (adjusted odds ratio (aOR)=0.58 (95% CI 0.35-0.97); p-value=0.04). Patients with obesity had reduced odds for a CT examination. No association was found between obesity status and US utilization. African-American patients had decreased odds for IAIs, CT scans and US examinations after adjustment which could be related to MFI type.

CONCLUSIONS

Obesity appears to reduce the odds for pediatric IAIs and CT scans, but not for US examinations. Selection bias is possible due to injury severity and missing or excluded weight data. Further research is needed in other pediatric populations with obesity and blunt injuries.

What is the inter-rater agreement of injury classification using the WHO minimum data set for emergency medical teams?

Background

In 2017, the WHO produced its first minimum data set (MDS) for emergency medical team (EMT) daily reporting during the sudden-onset disasters (SODs), following expert consensus. The MDS was deliberately designed to be simple in order to improve the rate of data capture; however, it is new and untested. This study assesses the inter-rater agreement between practitioners when performing the injury aspect of coding within the WHO EMT MDS.

Methods

25 clinical case vignettes were developed, reflecting potential injuries encountered in an SOD. These were presented online from April to July 2018 to practitioners who have experience of/training in managing patients in SODs The practitioners were from UK-Med’s members, Australian Medical Assistance Team’s Northern Territory members and New Zealand Medical Assistance Team members. Practitioners were asked to code injuries according to WHO EMT MDS case classifications. Randolph’s kappa statistic for free-marginal multirater data was calculated for the whole dataset as well as subgroups to ascertain inter-rater agreement.

Results

86 practitioners responded (20.6% response rate), giving >2000 individual case responses. Overall agreement was moderate at 67.9% with a kappa of 0.59 (95% CI 0.49 to 0.69). Despite subgroups of paramedics (kappa 0.63, 95% CI 0.53 to 0.72), doctors (kappa 0.61, 95% CI 0.52 to 0.69) and those with disaster experience (kappa 0.62, 95% CI 0.52 to 0.71) suggesting slightly higher agreement, their CIs (and those of other subgroups) suggest overall similar and moderate levels of practitioner agreement in classifying injuries according to the MDS categories.

Conclusions

An inter-rater agreement of 0.59 is moderate, at best, however, it gives ministries of health some sense of how tightly they may interpret injury data derived from daily reports using WHO EMT MDS. Furthermore, this kappa is similar to established but more complex (thus more contextually impractical) injury scores. Similar studies, with weighting for injury likelihood using sample data from SODs would further refine the level of expected inter-rater agreement.

Correlating injury severity scores and major trauma volume using a state-wide in-patient administrative dataset linked to trauma registry data-A retrospective analysis from New South Wales Australia

INTRODUCTION

Trauma registries are used to analyse and report activity and benchmark quality of care at designated facilities within a trauma system. These capabilities may be enhanced with the incorporation of administrative and electronic medical record datasets, but are currently limited by the use of different injury coding systems between trauma and administrative datasets.

OBJECTIVES

Use an Abbreviated Injury Scale to International Classification of Disease (AIS-ICD) mapping tool to correlate estimated injury severity scores and major trauma volume based on administrative data collections with trauma registry data.

METHODS

Adult trauma cases were identified from the New South Wales Trauma Registry between 2012 and 2016 and linked probabilistically using age, facility and date of facility arrival to the Admitted Patient Data Collection (APDC). Estimated Injury Severity Scores (ISS) were derived using the AIS-ICD mapping tool applied to diagnoses contained in the APDC.

RESULTS

A total of eligible 13,439 cases were analysed. The overall correlation between trauma registry ISS and ISS estimated from APDC using the AIS-ICD mapping tool was low to moderate (Spearman Rho 0.41 95%CI 0.40, 0.43). Based on an estimated ISS cut-off value of 8, there was high correlation between estimated trauma volume and the number of major trauma cases at each facility (Spearman Rho 0.98, 95%CI 0.95, 0.99). Trauma Revised Injury Severity Score (TRISS) was associated with only slightly higher mortality prediction performance compared to estimated ISS (AUROC 0.76 95%CI 0.75, 0.78 versus AUROC 0.74 95%CI 0.73, 0.76).

CONCLUSION

A low to moderate correlation exists between individual patient ISS scores based on AIS to ICD mapping of in-patient data collection, but a high correlation for overall major trauma volume using the AIS-ICD mapping at facility level with comparable TRISS mortality prediction.

Injury coding in a national trauma registry: a one-year validation audit in a level 1 trauma centre

Background

Hospitals must improve patient safety and quality continuously. Clinical quality registries can drive such improvement. Trauma registries code injuries according to the Abbreviated Injury Scale (AIS) and benchmark outcomes based on the Injury Severity Score (ISS) and New ISS (NISS). The primary aim of this study was to validate the injury codes and severities registered in a national trauma registry. Secondarily, we aimed to examine causes for missing and discordant codes, to guide improvement of registry data quality.

Methods

We conducted an audit and established an expert coder group injury reference standard for patients met with trauma team activation in 2015 in a Level 1 trauma centre. Injuries were coded according to the AIS. The audit included review of all data in the electronic health records (EHR), and new interpretation of all images in the picture archiving system. Validated injury codes were compared with the codes registered in the registry. The expert coder group’s interpretations of reasons for discrepancies were categorised and registered. Inter-rater agreement between registry data and the reference standard was tested with Bland–Altman analysis.

Results

We validated injury data from 144 patients (male sex 79.2%) with median age 31 (inter quartile range 19–49) years. The total number of registered AIS codes was 582 in the registry and 766 in the reference standard. All injuries were concordantly coded in 62 (43.1%) patients. Most non-registered codes (n = 166 in 71 (49.3%) patients) were AIS 1, and information in the EHR overlooked by registrars was the dominating cause. Discordant coding of head injuries and extremity fractures were the most common causes for 157 discordant AIS codes in 74 (51.4%) patients. Median ISS (9) and NISS (12) for the total population did not differ between the registry and the reference standard.

Conclusions

Concordance between the codes registered in the trauma registry and the reference standard was moderate, influencing individual patients’ injury codes validity and ISS/NISS reliability. Nevertheless, aggregated median group ISS/NISS reliability was acceptable.

The reliability and accuracy of operational system data in a nationwide helicopter emergency medical services mission database

AIM

The aim of this study was to evaluate the reliability and accuracy of documentation in FinnHEMS database, which is a nationwide helicopter emergency service (HEMS) clinical quality registry.

METHODS

This is a nationwide study based on written fictional clinical scenarios. Study subjects were HEMS physicians and paramedics, who filled in the clinical quality registry based on the clinical scenarios. The inter-rater -reliability of the collected data was analyzed with percent agreement and free-marginal multi-rater kappa.

RESULTS

Dispatch coding had a percent agreement of 91% and free-marginal multi-rater kappa value of 0.83. Coding for transportation or mission cancellation resulted in an agreement of 84% and free-marginal kappa value of 0.68. An agreement of 82% and a kappa value of 0.73 for dispatcher coding was found. Mission end, arrival at hospital and HEMS unit dispatch -times had agreements from 80 to 85% and kappa values from 0.61 to 0.73. The emergency call to dispatch centre time had an agreement of 71% and kappa value of 0.56. The documentation of pain had an agreement of 73% on both the first and second measurements. All other vital parameters had less than 70% agreement and 0.40 kappa value in the first measurement. The documentation of secondary vital parameter measurements resulted in agreements from 72 to 91% and kappa values from 0.43 to 0.64.

CONCLUSION

Data from HEMS operations can be gathered reliably in a national clinical quality registry. This study revealed some inaccuracies in data registration and data quality, which are important to detect to improve the overall reliability and validity of the HEMS clinical quality register.

Are Pre-hospital Trauma Deaths Preventable? A Systematic Literature Review

BACKGROUND

The first and largest peak of trauma mortality is encountered on the trauma site. The aim of this study was to determine whether these trauma-related deaths are preventable. We performed a systematic literature review with a focus on pre-hospital preventable deaths in severely injured patients and their causes.

METHODS

Studies published in a peer-reviewed journal between January 1, 1990 and January 10, 2018 were included. Parameters of interest: country of publication, number of patients included, preventable death rate (PP = potentially preventable and DP = definitely preventable), inclusion criteria within studies (pre-hospital only, pre-hospital and hospital deaths), definition of preventability used in each study, type of trauma (blunt versus penetrating), study design (prospective versus retrospective) and causes for preventability mentioned within the study.

RESULTS

After a systematic literature search, 19 papers (total 7235 death) were included in this literature review. The majority (63.1%) of studies used autopsies combined with an expert panel to assess the preventability of death in the patients. Pre-hospital death rates range from 14.6 to 47.6%, in which 4.9-11.3% were definitely preventable and 25.8-42.7% were potentially preventable. The most common (27-58%) reason was a delayed treatment of the trauma victims, followed by management (40-60%) and treatment errors (50-76.6%).

CONCLUSION

According to our systematic review, a relevant amount of the observed mortality was described as preventable due to delays in treatment and management/treatment errors. Standards in the pre-hospital trauma system and management should be discussed in order to find strategies to reduce mortality.

[Data content of the TraumaRegister DGU® : Results of a random sample control]

BACKGROUND

Registries are becoming increasingly more important in clinical research. The TraumaRegister DGU® of the German Society for Trauma Surgery plays an excellent role with respect to the care of severely injured patients.

AIM

Within the framework of this investigation the quality of data provided by this registry was to be verified.

MATERIAL AND METHODS

Certified hospitals participating in the TraumaNetzwerk DGU® of the German Society for Trauma Surgery are obliged to submit data of treated severely injured patients to the TraumaRegister DGU®. Participating hospitals have to undergo a re-certification process every 3 years. Within the framework of this re-audit, data from 5 out of 8 randomly chosen patient cases included in the registry are controlled and compared to the patient files of the certified hospital. In the present investigation discrepancies concerning data provided were documented and the pattern of deviation was analyzed.

RESULTS

The results of 1075 re-certification processes carried out in 631 hospitals including the documentation of 5409 checked patient cases from 2012-2017 were analyzed. The highest number of discrepancies detected concerned the documented time until initial CT (15.8%) and the lowest concerned the discharge site (3.2%). The majority of data sheets with discrepancies showed deviations in only one out of seven checked parameters. Interestingly, large trauma centers with a high throughput of severely injured patients showed the most deviations.

CONCLUSION

The present investigation underlines the importance of standardized checks concerning data provided for registries in order to be able to guarantee an improvement in entering data.

Maxillofacial injuries in severely injured patients after road traffic accidents-a retrospective evaluation of the TraumaRegister DGU® 1993-2014

Objectives

It was the aim of the study to analyse the prevalence of maxillofacial trauma (MFT) in severely injured patients after road traffic accidence (RTA) and to investigate associated factors.

Materials and methods

In a retrospective study, data from patients after RTA by the TraumaRegister DGU® from 1993 to 2014 were evaluated for demographical and injury characteristics. The predictor variable was mechanism of injury and the outcome variables were type of injury, severity and hospital resources utilization.

Results

During the investigation period, n = 62,196 patients were enclosed with a prevalence of maxillofacial injuries of 20.3% (MFT positive). The injury severity score of MFT-positive patients was higher than in the MTF-negative subgroup (27 ± 12.8 vs. 23.0 ± 12.7). If MFT positive, 39.8% show minor, 37.1% moderate, 21.5% serious and 1.6% severe maxillofacial injuries. Injuries of the midface occurred in 60.3% of MTF-positive patients. A relevant blood loss (> 20% of total blood volume) occurred in 1.9%. MFT-positive patients had a higher coincidence with cervical spine fractures (11.3% vs. 7.8%) and traumatic brain injuries (62.6% vs. 34.8%) than MFT-negative patients. There was a noticeable decrease in the incidence of facial injuries in car/truck drivers during the study period.

Conclusions

Every 5th patient after RTA shows a MFT and the whole trauma team must be aware that this indicates a high prevalence of traumatic brain and cervical spine injuries.

Clinical relevance

Even if sole injuries of the face are seldom life threatening, maxillofacial expertise in interdisciplinary trauma centres is strongly recommended.

A priori prediction of the probability of survival in vehicle crashes using anthropomorphic test devices and human body models

Objective: In the development of restraint systems, anthropomorphic test devices (ATDs) and human body models (HBMs) are used to estimate occupant injury risks. Due to conflicting objectives, this approach limits an injury severity risk tradeoff between the different body regions. Therefore, we present and validate a protocol for the aggregation of injury risks of body regions to a probability of survival (PoS). Methods: Injuries were clustered in regions similar to ATD or HBM investigations and the most severe injury as rated by the Maximum Abbreviated Injury Scale (MAIS) per body region was determined. Each injury was transformed into a dichotomous variable with regard to the injury severity level (e.g., MAIS 3+) whose injury risk was computed using the German In-Depth Accident Study (GIDAS) and NASS-CDS databases. Without loss of generality, we focus on 2 body regions-Head/face/neck (HFN) and chest (C)-at the MAIS 3+ level. The PoS was calculated using injury outcomes from the databases. The method of predicting PoS was validated by stratifying the database by crash type and technical crash severity. Results: The PoS of occupants injured in both HFN and C at the AIS 3+ level was found to be lower, at a statistically significant level, than that of occupants with AIS 3+ injuries to just one of the body regions. Focusing on occupants with only one body region injured at the AIS 3+ level, HFN injuries tended to decrease PoS more than chest injuries. For the validation cases, observed PoS could be reproduced in the majority of cases. When comparing predicted to observed values, a correlation of R2 = 0.92 was observed when not taking the restraint system into account. Focusing on frontal crashes, the correlation was R2 = 0.89. Considering only belted occupants, R2 increased to 0.93, whereas for cases with deployed airbag systems the R2 decreased to 0.68. The PoS for side crashes is reproduced with R2= 0.97 independent of the restraint system; it was 0.95 with belted occupants and 0.55 when also factoring in airbag deployment. Conclusions: The method showed an excellent predictive capability when disregarding the restraint system, or restraint-specific subgroups, for the considered validation cases.

Collecting core data in physician-staffed pre-hospital helicopter emergency medical services using a consensus-based template: international multicentre feasibility study in Finland and Norway

BACKGROUND

Comparison of services and identification of factors important for favourable patient outcomes in emergency medical services (EMS) is challenging due to different organization and quality of data. The purpose of the present study was to evaluate the feasibility of physician-staffed EMS (p-EMS) to collect patient and system level data by using a consensus-based template.

METHODS

The study was an international multicentre observational study. Data were collected according to a template for uniform reporting of data from p-EMS using two different data collection methods; a standard and a focused data collection method. For the standard data collection, data were extracted retrospectively for one year from all FinnHEMS bases and for the focused data collection, data were collected prospectively for six weeks from four selected Norwegian p-EMS bases. Completeness rates for the two data collection methods were then compared and factors affecting completeness rates and template feasibility were evaluated. Standard Chi-Square, Fisher's Exact Test and Mann-Whitney U Test were used for group comparison of categorical and continuous data, respectively, and Kolomogorov-Smirnov test for comparison of distributional properties.

RESULTS

All missions with patient encounters were included, leaving 4437 Finnish and 128 Norwegian missions eligible for analysis. Variable completeness rates indicated that physiological variables were least documented. Information on pain and respiratory rate were the most frequently missing variables with a standard data collection method and systolic blood pressure was the most missing variable with a focused data collection method. Completeness rates were similar or higher when patients were considered severely ill or injured but were lower for missions with short patient encounter. When a focused data collection method was used, completeness rates were higher compared to a standard data collection method.

CONCLUSIONS

We found that a focused data collection method increased data capture compared to a standard data collection method. The concept of using a template for documentation of p-EMS data is feasible in physician-staffed services in Finland and Norway. The greatest deficiencies in completeness rates were evident for physiological parameters. Short missions were associated with lower completeness rates whereas severe illness or injury did not result in reduced data capture.

Comparison of two simple models for prediction of short term mortality in patients after severe traumatic brain injury

INTRODUCTION

The subscale motor score of Glasgow Coma Scale (msGCS) and the Abbreviated Injury Score of head region (HAIS) are validated prognostic factors in traumatic brain injury (TBI). The aim was to compare the prognostic performance of a HAIS-based prediction model including HAIS, pupil reactivity and age, and the reference prediction model including msGCS in emergency department (ED), pupil reactivity and age.

METHODS

Secondary analysis of a prospective epidemiological study including patients after severe TBI (HAIS > 3) with follow-up from the time of accident until 14 days or earlier death was performed in Switzerland. Performance of prediction, based on accuracy of discrimination [area under the receiver-operating curve (AUROC)], calibration (Hosmer-Lemeshow test) and validity (bootstrapping with 2000 repetitions to correct) for optimism of the two prediction models were investigated. A non-inferiority approach was performed and an a priori threshold for important differences was established.

RESULTS

The cohort included 808 patients [median age 56 {inter-quartile range (IQR) 33-71}, median motor part of GCS in ED 1 (1-6), abnormal pupil reactivity 29.0%] with a death rate of 29.7% at 14 days. The accuracy of discrimination was similar (AUROC HAIS-based prediction model: 0.839; AUROC msGCS-based prediction model: 0.826, difference of the 2 AUROC 0.013 (-0.007 to 0.037). A similar calibration was observed (Hosmer-Lemeshow X² 11.64, p = 0.168 vs. Hosmer-Lemeshow X² 8.66, p = 0.372). Internal validity of HAIS-based prediction model was high (optimism corrected AUROC: 0.837).

CONCLUSIONS

Performance of prediction for short-term mortality after severe TBI with HAIS-based prediction model was non-inferior to reference prediction model using msGCS as predictor.

Assessment of polytraumatized patients according to the Berlin Definition: Does the addition of physiological data really improve interobserver reliability?

BACKGROUND

Several new definitions for categorizing the severely injured as the Berlin Definition have been developed. Here, severely injured patients are selected by additive physiological parameters and by the general Abbreviated Injury Scale (AIS)-based assessment. However, all definitions should conform to an AIS severity coding applied by an expert. We examined the dependence of individual coding on defining injury severity in general and in identifying polytrauma according to several definitions. A precise definition of polytrauma is important for quality management.

METHODS

We investigated the interobserver reliability (IR) between several polytrauma definitions for identifying polytrauma using several cut-off levels (ISS ≥16, ≥18, ≥20, ≥25 points, and the Berlin Definition). One hundred and eighty-seven patients were included for analyzing IR of the polytrauma definitions. IR for polytrauma definitions was assessed by Cohen's kappa.

RESULTS

IR for identifying polytrauma according to the relevant definitions showed moderate agreement (<0.60) in the ISS cutoff categories (ISS ≥16, ≥18, and ≥20 points), while ISS ≥25 points just reached substantial agreement (0.62) and the Berlin Definition demonstrated a correlation of 0.77 which is nearly perfect agreement (>0.80).

CONCLUSION

Compared with the ISS-based definitions of polytrauma, the Berlin Definition proved less dependent on the individual rater. This underlines the need to redefine the selection of severely injured patients. Using the Berlin Definition for identifying polytrauma could improve the comparability of patient data across studies, in trauma center benchmarking, and in quality assurance.

Trauma Early Mortality Prediction Tool (TEMPT) for assessing 28-day mortality

Background

Prior mortality prediction models have incorporated severity of anatomic injury quantified by Abbreviated Injury Severity Score (AIS). Using a prospective cohort, a new score independent of AIS was developed using clinical and laboratory markers present on emergency department presentation to predict 28-day mortality.

Methods

All patients (n=1427) enrolled in an ongoing prospective cohort study were included. Demographic, laboratory, and clinical data were recorded on admission. True random number generator technique divided the cohort into derivation (n=707) and validation groups (n=720). Using Youden indices, threshold values were selected for each potential predictor in the derivation cohort. Logistic regression was used to identify independent predictors. Significant variables were equally weighted to create a new mortality prediction score, the Trauma Early Mortality Prediction Tool (TEMPT) score. Area under the curve (AUC) was tested in the validation group. Pairwise comparison of Trauma Injury Severity Score (TRISS), Revised Trauma Score, Glasgow Coma Scale, and Injury Severity Score were tested against the TEMPT score.

Results

There was no difference between baseline characteristics between derivation and validation groups. In multiple logistic regression, a model with presence of traumatic brain injury, increased age, elevated systolic blood pressure, decreased base excess, prolonged partial thromboplastin time, increased international normalized ratio (INR), and decreased temperature accurately predicted mortality at 28 days (AUC 0.93, 95% CI 0.90 to 0.96, P<0.001). In the validation cohort, this score, termed TEMPT, predicted 28-day mortality with an AUC 0.94 (95% CI 0.92 to 0.97). The TEMPT score preformed similarly to the revised TRISS score for severely injured patients and was highly predictive in those having mild to moderate injury.

Discussion

TEMPT is a simple AIS-independent mortality prediction tool applicable very early following injury. TEMPT provides an AIS-independent score that could be used for early identification of those at risk of doing poorly following even minor injury.

Level of evidence

Level II.

The role of whole-body computed tomography in the diagnosis of thoracic injuries in severely injured patients - a retrospective multi-centre study based on the trauma registry of the German trauma society (TraumaRegister DGU®)

Background

Thoracic injuries are a leading cause of death in polytrauma patients. Early diagnosis and treatment are of paramount importance. Whole-body computed tomography (WBCT) has largely replaced traditional imaging techniques such as conventional radiographs and focused computed tomography (CT) as diagnostic tools in severely injured patients. It is still unclear whether WBCT has led to higher rates of diagnosis of thoracic injuries and thus to a change in outcomes.

Methods

In a retrospective study based on the trauma registry of the German Trauma Society (TraumaRegister DGU^®), we analysed data from 16,545 patients who underwent treatment in 59 hospitals between 2002 and 2012 (ISS ≥ 9). The 3 years preceding and the 3 years following the introduction of WBCT as a standard imaging modality for the investigation of severely injured patients were assessed for every hospital. Accordingly, patients were assigned to either the pre-WBCT or the WBCT group. We compared the numbers of thoracic injuries and the outcomes of patients before and after the routine use of WBCT.

Results

A total of 13,564 patients (pre-WBCT: n = 5005, WBCT: n = 8559) were included. Relevant thoracic injuries were detected in 47.8%. There were no major differences between the patient groups in injury severity (pre-WBCT: median ISS 21; WBCT: median ISS 22), injury patterns and demographics. After the introduction of WBCT, only minor changes were observed regarding the rates of most thoracic injuries. Clinically relevant injuries were pulmonary contusions (pre-WBCT: 18.5%; WBCT: 28.7%), injuries to the lung parenchyma (pre-WBCT: 12.6%; WBCT: 5.9%), multiple rib fractures (pre-WBCT: 10.6%; WBCT: 21.6%), and pneumothoraces (pre-WBCT: 17.3%; WBCT: 21.6%). The length of stay in the intensive care unit (pre-WBCT: 10.8 days; WBCT: 9.7 days) and in hospital (pre-WBCT: 26.2 days; WBCT: 23.3 days) decreased. There was no difference in overall mortality (pre-WBCT: 15.5%; WBCT: 15.6%).

Conclusions

The routine use of WBCT in the trauma room setting has led to changes in patient management that are not reflected in the rates of diagnosis of severe thoracic injuries (e.g. tension pneumothoraces, cardiac injuries, arterial injuries). By contrast, there was a relevant increase in the rates of diagnosis of minor thoracic injuries, which, however, did not result in an improvement in survival prognosis.

Evaluating helicopter emergency medical missions: a reliability study of the HEMS benefit and NACA scores

BACKGROUND

The benefits of the Helicopter Emergency Medical Service (HEMS) and dispatch accuracy are continuously debated, and a widely accepted score to measure the benefits of the mission is lacking. The HEMS Benefit Score (HBS) has been used in Finnish helicopter emergency medical services, but studies are lacking. The National Advisory Committee for Aeronautics (NACA) score is widely used to measure the severity of illness or injury in the pre-hospital setting, but it has many critics due to its subjectivity. We investigated the inter-rater and rater-against-reference reliability of these scores.

METHODS

Twenty-five fictional HEMS missions were created by an expert panel. A total of 22 pre-hospital physicians were recruited to participate in the study from two different HEMS bases. The participants received written instructions on the use of the scores. Intraclass correlation coefficients (ICCs) and mean differences between rater-against-reference values were calculated.

RESULTS

A total of 17 physicians participated in the study. The ICC was 0.70 (95% CI 0.57-0.83) for the HBS and 0.65 (95% CI 0.51-0.79) for the NACA score. Mean differences between references and raters were -0.09 (SD 0.72) for the HBS and 0.28 (SD 0.61) for the NACA score, indicating that raters scored some lower NACA values than reference values formed by an expert panel.

CONCLUSION

The HBS and NACA score had substantial inter-rater reliability. In addition, the rater-against-reference values were acceptable, though large differences were observed between individual raters and references in some clinical cases.

Comparison of Two Predictive Models for Short-Term Mortality in Patients after Severe Traumatic Brain Injury

The Glasgow Coma Scale (GCS) and the Abbreviated Injury Score of the head region (HAIS) are validated prognostic factors in traumatic brain injury (TBI). The aim of this study was to compare the prognostic performance of an alternative predictive model including motor GCS, pupillary reactivity, age, HAIS, and presence of multi-trauma for short-term mortality with a reference predictive model including motor GCS, pupil reaction, and age (IMPACT core model). A secondary analysis of a prospective epidemiological cohort study in Switzerland including patients after severe TBI (HAIS >3) with the outcome death at 14 days was performed. Performance of prediction, accuracy of discrimination (area under the receiver operating characteristic curve [AUROC]), calibration, and validity of the two predictive models were investigated. The cohort included 808 patients (median age, 56; interquartile range, 33-71), median GCS at hospital admission 3 (3-14), abnormal pupil reaction 29%, with a death rate of 29.7% at 14 days. The alternative predictive model had a higher accuracy of discrimination to predict death at 14 days than the reference predictive model (AUROC 0.852, 95% confidence interval [CI] 0.824-0.880 vs. AUROC 0.826, 95% CI 0.795-0.857; p < 0.0001). The alternative predictive model had an equivalent calibration, compared with the reference predictive model Hosmer-Lemeshow p values (Chi2 8.52, Hosmer-Lemeshow p = 0.345 vs. Chi2 8.66, Hosmer-Lemeshow p = 0.372). The optimism-corrected value of AUROC for the alternative predictive model was 0.845. After severe TBI, a higher performance of prediction for short-term mortality was observed with the alternative predictive model, compared with the reference predictive model.

Methodological Challenges in Studies Comparing Prehospital Advanced Life Support with Basic Life Support

Determining the most appropriate level of care for patients in the prehospital setting during medical emergencies is essential. A large body of literature suggests that, compared with Basic Life Support (BLS) care, Advanced Life Support (ALS) care is not associated with increased patient survival or decreased mortality. The purpose of this special report is to synthesize the literature to identify common study design and analytic challenges in research studies that examine the effect of ALS, compared to BLS, on patient outcomes. The challenges discussed in this report include: (1) choice of outcome measure; (2) logistic regression modeling of common outcomes; (3) baseline differences between study groups (confounding); (4) inappropriate statistical adjustment; and (5) inclusion of patients who are no longer at risk for the outcome. These challenges may affect the results of studies, and thus, conclusions of studies regarding the effect of level of prehospital care on patient outcomes should require cautious interpretation. Specific alternatives for avoiding these challenges are presented. Li T , Jones CMC , Shah MN , Cushman JT , Jusko TA . Methodological challenges in studies comparing prehospital Advanced Life Support with Basic Life Support. Prehosp Disaster Med. 2017;32(4):444-450.

Major influence of interobserver reliability on polytrauma identification with the Injury Severity Score (ISS): Time for a centralised coding in trauma registries?

OBJECTIVE

The Abbreviated Injury Scale (AIS) and the Injury Severity Score (ISS) find increasingly widespread use to assess trauma burden and to perform interhospital benchmarking through trauma registries. Since 2015, public resource allocation in Switzerland shall even be derived from such data. As every trauma centre is responsible for its own coding and data input, this study aims at evaluating interobserver reliability of AIS and ISS coding.

METHODS

Interobserver reliability of the AIS and ISS is analysed from a cohort of 50 consecutive severely injured patients treated in 2012 at our institution, coded retrospectively by 3 independent and specifically trained observers.

RESULTS

Considering a cutoff ISS≥16, only 38/50 patients (76%) were uniformly identified as polytraumatised or not. Increasing the cut off to ≥20, this increased to 41/50 patients (82%). A difference in the AIS of ≥ 1 was present in 261 (16%) of possible codes. Excluding the vast majority of uninjured body regions, uniformly identical AIS severity values were attributed in 67/193 (35%) body regions, or 318/579 (55%) possible observer pairings.

CONCLUSION

Injury severity all too often is neither identified correctly nor consistently when using the AIS. This leads to wrong identification of severely injured patients using the ISS. Improving consistency of coding through centralisation is recommended before scores based on the AIS are to be used for interhospital benchmarking and resource allocation in the treatment of severely injured patients.

Mobile health technology transforms injury severity scoring in South Africa

BACKGROUND

The burden of data collection associated with injury severity scoring has limited its application in areas of the world with the highest incidence of trauma.

MATERIAL AND METHODS

Since January 2014, electronic records (electronic Trauma Health Records [eTHRs]) replaced all handwritten records at the Groote Schuur Hospital Trauma Unit in South Africa. Data fields required for Glasgow Coma Scale, Revised Trauma Score, Kampala Trauma Score, Injury Severity Score (ISS), and Trauma Score-Injury Severity Score calculations are now prospectively collected. Fifteen months after implementation of eTHR, the injury severity scores were compared as predictors of mortality on three accounts: (1) ability to discriminate (area under receiver operating curve, ROC); (2) ability to calibrate (observed versus expected ratio, O/E); and (3) feasibility of data collection (rate of missing data).

RESULTS

A total of 7460 admissions were recorded by eTHR from April 1, 2014 to July 7, 2015, including 770 severely injured patients (ISS > 15) and 950 operations. The mean age was 33.3 y (range 13-94), 77.6% were male, and the mechanism of injury was penetrating in 39.3% of cases. The cohort experienced a mortality rate of 2.5%. Patient reserve predictors required by the scores were 98.7% complete, physiological injury predictors were 95.1% complete, and anatomic injury predictors were 86.9% complete. The discrimination and calibration of Trauma Score-Injury Severity Score was superior for all admissions (ROC 0.9591 and O/E 1.01) and operatively managed patients (ROC 0.8427 and O/E 0.79). In the severely injured cohort, the discriminatory ability of Revised Trauma Score was superior (ROC 0.8315), but no score provided adequate calibration.

CONCLUSIONS

Emerging mobile health technology enables reliable and sustainable injury severity scoring in a high-volume trauma center in South Africa.

Criteria for level 1 and level 2 trauma codes: Are pelvic ring injuries undertriaged?

AIM: To determine the association of unstable pelvic ring injuries with trauma code status.

METHODS: A retrospective review of all pelvic ring injuries at a single academic center from July 2010 to June 2013 was performed. The trauma registry was used to identify level 1 and level 2 trauma codes for each injury. The computed tomography scans in all patients were classified as stable or unstable using the Abbreviated Injury Scale. Pelvic injury classifications in level 1 and level 2 groups were compared. Patient disposition at discharge in level 1 and level 2 groups were also compared.

RESULTS: There were 108 level 1 and 130 level 2 blunt trauma admissions. In the level 1 group, 67% of pelvic injuries were classified as stable fracture patterns and 33% were classified as unstable. In the level 2 group, 62% of pelvic injuries were classified as stable fracture patterns and 38% were classified as unstable. level 1 trauma code was not associated with odds of having an unstable fracture pattern (OR = 0.83, 95%CI: 0.48-1.41, P = 0.485). In the level 1 group with unstable pelvic injuries, 33% were discharged to home, 36% to a rehabilitation facility, and 32% died. In the level 2 group with unstable pelvic injuries, 65% were discharged to home, 31% to a rehabilitation facility, and 4% died. For those with unstable pelvic fractures (n = 85), assignment of a level 2 trauma code was associated with reduced odds of death (OR = 0.07, 95%CI: 0.01-0.35, P = 0.001) as compared to being discharged to home.

CONCLUSION: Trauma code level assignment is not correlated with severity of pelvic injury. Because an unstable pelvis can lead to hemodynamic instability, these injuries may be undertriaged.

Clinical Outcomes of Surgical Stabilization of Flail Chest Injury

INTRODUCTION

Recent reported success in surgical stabilization of flail chest has been described in small series, but scant evidence exists for this procedure in the orthopaedic literature.

METHODS

We reviewed 88 consecutive patients who underwent surgical stabilization of flail chest, along with 88 consecutive patients with flail chest who underwent traditional closed management before initiation of our algorithm change to surgical management.

RESULTS

Surgical stabilization of flail chest injuries led to statistically significant decreases in hospital length of stay, ventilator-dependency time, pneumonia, tracheostomy, and mortality rate. In addition, the presence of pulmonary contusion did not eliminate the significant improvements in the aforementioned variables.

DISCUSSION

Surgical stabilization of flail chest with modern techniques and implants provides significant improvements in both mortality and short-term outcomes. Although pulmonary contusion decreased overall outcomes across both cohorts, this factor did not alter the ability of rib fixation to improve outcomes.

Misclassification of Pelvic Ring Injuries in the National Trauma Data Bank

BACKGROUND

The American College of Surgeons has advocated for all trauma centers to participate in the National Trauma Data Bank (NTDB); however, no previous study has evaluated the accuracy of coding included in this data bank. The purpose of this study was to determine whether pelvic ring injuries are coded accurately in the NTDB and, if not, how they were misclassified.

METHODS

A retrospective review of all pelvic ring injuries based on Abbreviated Injury Scale (AIS) codes was performed at a single level I academic trauma center from July 2010 to June 2013. Thin-section computed tomography (CT) scans in all patients were reviewed and classified using AIS codes: posterior arch intact, incomplete posterior arch, or complete posterior arch. The surgeon was blinded to the AIS code from the registry. These CT-based classifications were then compared with the pelvic ring injury codes designated in the trauma registry for each patient to evaluate agreement.

RESULTS

Two hundred thirty-five patients with a mean age of 42 years had pelvic ring injuries in our registry. The agreement between trauma registry codes and CT reclassification was 24% in the intact group, 43% in the incomplete group, and 59% in the complete group. Using only the trauma registry codes, injuries were underclassified in 48% of the incomplete group and 76% of the intact group.

CONCLUSIONS

Many pelvic ring injuries are miscoded and misclassified in the NTDB. The etiology of this misclassification is unclear, but any research data mined from these databases should be regarded cautiously.

Outcome after red trauma alarm at an urban Swedish hospital: implications for prevention

AIMS

We applied the new injury severity scoring system and studied mechanisms of injury and risk factors for mortality, in order to find potential preventive measures, in the present Scandinavian trauma cohort triaged through red trauma alarm according to the Medical Emergency Triage and Treatment System.

METHODS

Individuals were identified in hospital and forensic records. New injury severity scoring system >15 was defined as major trauma. Inter-rater reliability of new injury severity scoring system was expressed as intra-class correlation coefficient with 95% confidence intervals.

RESULTS

There were 125 major and 303 minor traumas. The intra-class correlation coefficient was 0.83 (95% confidence intervals 0.58-0.94) for major trauma and intra-class correlation coefficient was 0.96 (95% confidence intervals 0.89-0.98) for minor trauma. Traffic (37%) and fall (31%) accidents were the leading mechanisms of injury. Elderly (aged ⩾65 years) were at an increased risk of fall accidents (p<0.001). The overall 3 month mortality rate was 10.3% (2% for new injury severity scoring system 16-24, 39% for new injury severity scoring system 25-40 and 68% for new injury severity scoring system >40). A higher new injury severity scoring system score (p<0.001), higher age (p<0.001), shock at admission (p<0.001), intensive care unit stay (p<0.004) and administration of massive red blood cell transfusion (p<0.048) were associated with mortality. Thirty-three patients underwent forensic autopsy and were tested positive for one or multiple drugs in 52% and 33%, respectively.

CONCLUSIONS

The high prevalence of detected drugs among those undergoing forensic toxicological examination suggests that toxicology screening should be integrated into all red trauma alarm admissions, which may have implications on prevention of future trauma morbidity and mortality.

Expanding pedestrian injury risk to the body region level: how to model passive safety systems in pedestrian injury risk functions

OBJECTIVE

Assessment of the effectiveness of advanced driver assistance systems (ADAS) plays a crucial role in accident research. A common way to evaluate the effectiveness of new systems is to determine the potentials for injury severity reduction. Because injury risk functions describe the probability of an injury of a given severity conditional on a technical accident severity (closing speed, delta V, barrier equivalent speed, etc.), they are predestined for such evaluations.

METHODS

Recent work has stated an approach on how to model the pedestrian injury risk in pedestrian-to-passenger car accidents as a family of functions. This approach gave explicit and easily interpretable formulae for the injury risk conditional on the closing speed of the car. These results are extended to injury risk functions for pedestrian body regions. Starting with a double-checked German In-depth Accident Study (GIDAS) pedestrian-to-car accident data set (N = 444) and a functional-anatomical definition of the body regions, investigations on the influence of specific body regions on the overall injury severity will be presented. As the measure of injury severity, the ISSx, a rescaled version of the well-known Injury Severity Score (ISS), was used. Though traditional ISS is computed by summation of the squares of the 3 most severe injured body regions, ISSx is computed by the summation of the exponentials of the Abbreviated Injury Scale (AIS) severities of the 3 most severely injured body regions. The exponentials used are scaled to fit the ISS range of values between 0 and 75.

RESULTS

Three body regions (head/face/neck, thorax, hip/legs) clearly dominated abdominal and upper extremity injuries; that is, the latter 2 body regions had no influence at all on the overall injury risk over the range of technical accident severities. Thus, the ISSx is well described by use of the injury codes from the same body regions for any pedestrian injury severity. As a mathematical consequence, the ISSx becomes explicitly decomposable into the 3 body regions and so are the risk functions as body region-specific risk functions. The risk functions for each body region are stated explicitly for different injury severity levels and compared to the real-world accident data.

CONCLUSIONS

The body region-specific risk functions can then be used to model the effect of improved passive safety systems. These modified body region-specific injury risk functions are aggregated to a new pedestrian injury risk function. Passive safety systems can therefore be modeled in injury risk functions for the first time. A short example on how the results can be used for assessing the effectiveness of new driver assistance systems concludes the article.

[Retrospective computation of the ISS in multiple trauma patients: Potential pitfalls and limitations of findings in full body CT scans]

INTRODUCTION

The Injury Severity Score (ISS) is a well-established anatomical scoring system for polytraumatized patients. However, any inaccuracy in the Abbreviated Injury Score (AIS) directly increases the ISS impreciseness. Using the full body computed tomography (CT) scan report, ISS computation can be associated with certain pitfalls. This study evaluates interpretation variations depending on radiological reports and indicates requirements to reliably determine the ISS.

MATERIALS AND METHODS

The ISS of 81 polytraumatized patients was calculated based on the full body CT scan report. If an injury could not be attributed to a precise AIS cipher, the minimal and maximal ISS was computed. Real ISS included all conducted investigations, intraoperative findings, and final medical reports. The differences in ISS min, ISS max, and ISS real were evaluated using the Kruskal-Wallis test (p<0.05) and plotted in a linear regression analysis.

RESULTS

Mean ISS min was 24.0 (± 0.7 SEM) points, mean ISS real 38.6 (±1.3 SEM) and mean ISS max was 48.3 (±1.4 SEM) points. All means were significantly different compared to one another (p<0.001). The difference between possible and real ISS showed a distinctive variation. Mean deviation was 9.7 (±0.9 SEM) points downward and 14.5 (±1.1 SEM) points upward. The difference between deviation to ISS min and ISS max was highly significant (p<0.001).

CONCLUSION

Objectification of injury severity in polytraumatized patients using the ISS is an internationally well-established method in clinical and scientific settings. The full body CT scan report must meet distinct criteria and has to be written in acquaintance to the AIS scale if intended to be used for correct ISS computation.

Missing patients in a regional trauma registry: incidence and predictors

BACKGROUND

Trauma systems have data registries in order to describe and evaluate (the quality of) trauma care. If results between centres and countries (benchmarking) are to be compared, data has to be accurate, reliable and complete. All trauma registries deal with incompleteness. A contributor to incompleteness of the data is failure to include patients that fulfil the criteria; the so-called missing patients. The aim of this study is to assess the number of missing patients in our regional trauma registry and to identify predictors for being missing from the trauma registry.

METHODS

A random sample was taken. Four calendar weeks from 2012 were selected and medical files of all consecutive presentations to the emergency department or trauma room during those weeks were studied. Patients who were already correctly included in the trauma registry were assigned to the 'included' group and patients who should have been but were not to the 'missing' group. Multivariable logistic regression analysis was performed to identify predictors for being missed from the trauma registry.

RESULTS

Of a total of 338 patients, 50 (15%) were identified as missing. Characteristics of the missing patients did not differ substantially from the included patients. Transfer to another hospital after initial assessment and presentation in a Level 3 hospital compared to a Level 1 hospital were independent predictors for being missed from the trauma registry, with an adjusted odds ratio of 5.86 (95% CI: 2.08-16.52) and 6.64 (95% CI: 1.86-23.78), respectively.

CONCLUSIONS

Overall, 15% of the patients who met the inclusion criteria of the trauma registry were not included in the registry. Special attention should be paid to patients who are transferred to other hospitals in the network after initial assessment and to registration in Level 3 hospitals.

Developing templates for uniform data documentation and reporting in critical care using a modified nominal group technique

BACKGROUND

Clinical practice in trauma and critical care is predominantly derived from quantitative observational cohort studies based on data retrospectively collected from medical records. Such data create uncontrolled bias and influence external and internal validity, thereby hindering systematic reviews. Templates or standards for uniform documenting and scientific reporting may result in high quality and internationally standardised data being collected on a regular basis, enhance large international multi-centre studies, and increase the quality of evidence. Templates or standards may be developed using multidisciplinary expert panel consensus methods.We present three consensus processes aimed at developing templates for documenting and scientific reporting. We discuss the advantages, limitations, and possible future improvements of our method.

METHODS

The template preparation was based on expert panel consensus derived through a modified nominal group technique (NGT) method that combined the traditional Delphi method with the traditional NGT method in a four-step process.

RESULTS

Standard templates for documenting and scientific reporting were developed for major trauma, pre-hospital advanced airway handling, and physician-staffed pre-hospital EMS. All templates were published in scientific journals.

CONCLUSION

Our modified NGT consensus method can successfully be used to establish templates for reporting trauma and critical care data. When used in a structured manner, the method uses recognised experts to achieve consensus, but based on our experiences, we recommend the consensus process to be followed by feasibility, reliability, and validity testing.