Refining the Trauma and Injury Severity Score (TRISS) to Measure the Performance of the UK Combat Casualty Care System

Effectiveness of Prehospital Critical Care Scene Response for Major Trauma: A Systematic Review

OBJECTIVES

Major trauma is a leading cause of morbidity and mortality worldwide. It is unclear if the addition of a critical care response unit (CCRU) with capabilities comparable to hospital emergency departments might improve outcomes following major trauma, when added to Basic or Advanced Life Support (BLS/ALS) prehospital care. This systematic review describes the evidence for a CCRU scene response model for major trauma.

METHODS

We searched Medline (Ovid), Embase (Ovid), Cochrane Central Register of Controlled Trials (Ovid), CINAHL (EBSCOhost), Science Citation Index Expanded (Web of Science), Conference Proceedings Citation Index - Science (Web of Science), LILACS (Latin American and Caribbean Health Sciences Literature) for relevant publications from 2003 to 2024. We included any study that compared CCRU and BLS/ALS care at the scene of major trauma, reported patient-focused outcomes, and utilized statistical methods to reduce bias and confounding. The risk of bias was assessed by two independent reviewers, using the ROBINS-I tool. Based on our a priori knowledge of the literature, a narrative analysis was chosen. The review was prospectively registered (PROSPERO ID CRD42023490668).

RESULTS

The search yielded 5243 unique records, of which 26 retrospective cohort studies and one randomized controlled trial met inclusion criteria. Sample sizes ranged from 308 to 153,729 patients. Eighteen of the 27 included studies showed associations between CCRUs and improved survival following trauma, which appear to be more consistently found in more critically injured and adult patients, as well as those suffering traumatic cardiac arrest. The remaining nine studies showed no significant difference in outcomes between CCRU and BLS/ALS care. Most studies demonstrated critical or severe risks of bias.

CONCLUSIONS

Current evidence examining CCRU scene response for major trauma suggests potential benefits in severely injury patients but is limited by overall low quality. Further high-quality research is required to confirm the benefits from CCRU scene response for major trauma.

ASA score is an independent predictor of 1-year outcome after moderate-to-severe traumatic brain injury

PURPOSE

This study aimed to investigate whether incorporating pre-injury health status, measured by the American Society of Anesthesiologists (ASA) score, improves outcome prediction models for moderate-to-severe traumatic brain injury (msTBI) patients.

METHODS

We conducted a retrospective single-center study of msTBI patients (2005-2021). The primary outcome was 1-year Glasgow Outcome Scale (GOS, dichotomized as GOS1-3 (unfavorable) vs. 4-5 (favorable)), and secondary outcome was 90-day mortality. Logistic regression evaluated the contribution of ASA score to the International Mission for Prognosis and Clinical Trials in Traumatic Brain Injury (IMPACT) core + CT outcome prediction model incorporating age, admission GCS, pupillary reactivity, Marshall CT classification, hypoxia, hypotension, epidural hematoma, and subarachnoid hemorrhage.

RESULTS

Among the 720 adult patients that were included 51% had an unfavorable GOS at 1 year. The 90-day mortality was 19%. ASA score and TRISS were independently associated with both outcomes (p < 0.001). Incorporating the ASA score to our IMPACT model significantly enhanced its explanatory value of dichotomized GOS (35% vs. 32% variance explained, p < 0.001) and improved the model's prognostic accuracy.

CONCLUSION

In this retrospective single-center cohort study, we found that ASA score improves existing prognostic models for msTBI. Incorporating this simple comorbidity measure could enhance outcome prediction and support more personalized acute management. Future prospective studies are needed to validate these results.

Understanding progressive tissue loss and wound burden in combat casualties: lessons learnt for future operational capability

Understanding tissue loss following injury is important due to its prevalence among the war-wounded and the impact it has on subsequent treatment and rehabilitation. Progressive tissue loss is a type of tissue loss that has complicated extremity injury in recent conflicts. It has resulted in more proximal residual limb lengths and has influenced rehabilitation. Quantifying wound burden in combat casualties remains a challenge due to poor quality of data sets that lack the capacity for detailed analysis. The aims of this article are to outline the current hurdles in attempting to quantify wound burden in combat casualties and to propose simple interventions to improve data capture for future analysis.

ASA-score is associated with 90-day mortality after complicated mild traumatic brain injury - a retrospective cohort study

PURPOSE

This study explores the association of the American Society of Anesthesiologists (ASA) score with 90-day mortality in complicated mild traumatic brain injury (mTBI) patients, and in trauma patients without a TBI.

METHODS

This retrospective study was conducted using a cohort of trauma patients treated at a level III trauma center in Stockholm, Sweden from January to December 2019. The primary endpoint was 90-day mortality. The population was identified using the Swedish Trauma registry. The Trauma and Injury Severity Score (TRISS) was used to estimate the likelihood of survival. Trauma patients without TBI (NTBI) were used for comparison. Data analysis was conducted using R software, and statistical analysis included univariate and multivariate logistic regression.

RESULTS

A total of 244 TBI patients and 579 NTBI patients were included, with a 90-day mortality of 8.2% (n = 20) and 5.4% (n = 21), respectively. Deceased patients in both cohorts were generally older, with greater comorbidities and higher injury severity. Complicated mTBI constituted 97.5% of the TBI group. Age and an ASA score of 3 or higher were independently associated with increased mortality risk in the TBI group, with odds ratios of 1.04 (95% 1.00-1.09) and 3.44 (95% CI 1.10-13.41), respectively. Among NTBI patients, only age remained a significant mortality predictor. TRISS demonstrated limited predictive utility across both cohorts, yet a significant discrepancy was observed between the outcome groups within the NTBI cohort.

CONCLUSION

This retrospective cohort study highlights a significant association between ASA score and 90-day mortality in elderly patients with complicated mTBI, something that could not be observed in comparative NTBI cohort. These findings suggest the benefit of incorporating ASA score into prognostic models to enhance the accuracy of outcome prediction models in these populations, though further research is warranted.

Injury scoring systems for blast injuries: a narrative review

Injury scoring systems can be used for triaging, predicting morbidity and mortality, and prognosis in mass casualty incidents. Recent conflicts and civilian incidents have highlighted the unique nature of blast injuries, exposing deficiencies in current scoring systems. Here, we classify and describe deficiencies with current systems used for blast injury. Although current scoring systems highlight survival trends for populations, there are several major limitations. The reliable prediction of mortality on an individual basis is inaccurate. Other limitations include the saturation effect (where scoring systems are unable to discriminate between high injury score individuals), the effect of the overall injury burden, lack of precision in discriminating between mechanisms of injury, and a lack of data underpinning scoring system coefficients. Other factors influence outcomes, including the level of healthcare and the delay between injury and presentation. We recommend that a new score incorporates the severity of injuries with the mechanism of blast injury. This may include refined or additional codes, severity scores, or both, being added to the Abbreviated Injury Scale for high-frequency, blast-specific injuries; weighting for body regions associated with a higher risk for death; and blast-specific trauma coefficients. Finally, the saturation effect (maximum value) should be removed, which would enable the classification of more severe constellations of injury. An early accurate assessment of blast injury may improve management of mass casualty incidents.

A Data Augmentation Method for War Trauma Using the War Trauma Severity Score and Deep Neural Networks

The demand for large-scale analysis and research of data on trauma from modern warfare is increasing day by day, but the amount of existing data is not sufficient to meet such demand. In this study, an integrated modeling approach incorporating a war trauma severity scoring algorithm (WTSS) and deep neural networks (DNN) is proposed. First, the proposed WTSS, which uses multiple non-linear regression based on the characteristics of war trauma data and the medical evaluation by an expert panel, performed a standardized assessment of an injury and predicts its trauma consequences. Second, to generate virtual injury, based on the probability of occurrence, the injured parts, injury types, and complications were randomly sampled and combined, and then WTSS was used to assess the consequences of the virtual injury. Third, to evaluate the accuracy of the predicted injury consequences, we built a DNN classifier and then trained it with the generated data and tested it with real data. Finally, we used the Delphi method to filter out unreasonable injuries and improve data rationality. The experimental results verified that the proposed approach surpassed the traditional artificial generation methods, achieved a prediction accuracy of 84.43%, and realized large-scale and credible war trauma data augmentation.

A Comparative Study Between Two Combat Injury Severity Scores

INTRODUCTION

In recent years, specific trauma scoring systems have been developed for military casualties. The objective of this study was to examine the discrepancies in severity scores of combat casualties between the Abbreviated Injury Scale 2005-Military (mAIS) and the Military Combat Injury Scale (MCIS) and a review of the current literature on the application of trauma scoring systems in the military setting.

METHODS

A cross-sectional, descriptive, and retrospective study was conducted between May 1, 2005, and December 31, 2014. The study population consisted of all combat casualties attended in the Spanish Role 2 deployed in Herat (Afghanistan). We used the New Injury Severity Score (NISS) as reference score. Severity of each injury was calculated according to mAIS and MCIS, respectively. The severity of each casualty was calculated according to the NISS based on the mAIS (Military New Injury Severity Score-mNISS) and MCIS (Military Combat Injury Scale-New Injury Severity Score-MCIS-NISS). Casualty severity were grouped by severity levels (mild-scores: 1-8, moderate-scores: 9-15, severe-scores: 16-24, and critical-scores: 25-75).

RESULTS

Nine hundred and eleven casualties were analyzed. Most were male (96.37%) with a median age of 27 years. Afghan patients comprised 71.13%. Air medevac was the main casualty transportation method (80.13). Explosion (64.76%) and gunshot wound (34.68%) mechanisms predominated. Overall mortality was 3.51%. Median mNISS and MCIS-NISS were similar in nonsurvivors (36 [IQR, 25-49] vs. [IQR, 25-48], respectively) but different in survivors, 9 (IQR, 4-17) vs. 5 (IQR, 2-13), respectively (P < .0001). The mNISS and MCIS-NISS were discordant in 34.35% (n = 313). Among cases with discordant severity scores, the median difference between mNISS and MCIS-NISS was 9 (IQR, 4-16); range, 1 to 57.

CONCLUSION

Our study findings suggest that discrepancies in injury severity levels may be observed in one in three of the casualties when using mNISS and MCIS-NISS.