Accuracy of pre-hospital triage tools for major trauma: a systematic review with meta-analysis and net clinical benefit

Enhancing Performance of the National Field Triage Guidelines Using Machine Learning: Development of a Prehospital Triage Model to Predict Severe Trauma

BACKGROUND

Prehospital trauma triage is essential to get the right patient to the right hospital. However, the national field triage guidelines proposed by the American College of Surgeons have proven to be relatively insensitive when identifying severe traumas.

OBJECTIVE

This study aimed to build a prehospital triage model to predict severe trauma and enhance the performance of the national field triage guidelines.

METHODS

This was a multisite prediction study, and the data were extracted from the National Trauma Data Bank between 2017 and 2019. All patients with injury, aged 16 years of age or older, and transported by ambulance from the injury scene to any trauma center were potentially eligible. The data were divided into training, internal, and external validation sets of 672,309; 288,134; and 508,703 patients, respectively. As the national field triage guidelines recommended, age, 7 vital signs, and 8 injury patterns at the prehospital stage were included as candidate variables for model development. Outcomes were severe trauma with an Injured Severity Score ≥16 (primary) and critical resource use within 24 hours of emergency department arrival (secondary). The triage model was developed using an extreme gradient boosting model and Shapley additive explanation analysis. The model's accuracy regarding discrimination, calibration, and clinical benefit was assessed.

RESULTS

At a fixed specificity of 0.5, the model showed a sensitivity of 0.799 (95% CI 0.797-0.801), an undertriage rate of 0.080 (95% CI 0.079-0.081), and an overtriage rate of 0.743 (95% CI 0.742-0.743) for predicting severe trauma. The model showed a sensitivity of 0.774 (95% CI 0.772-0.776), an undertriage rate of 0.158 (95% CI 0.157-0.159), and an overtriage rate of 0.609 (95% CI 0.608-0.609) when predicting critical resource use, fixed at 0.5 specificity. The triage model's areas under the curve were 0.755 (95% CI 0.753-0.757) for severe trauma prediction and 0.736 (95% CI 0.734-0.737) for critical resource use prediction. The triage model's performance was better than those of the Glasgow Coma Score, Prehospital Index, revised trauma score, and the 2011 national field triage guidelines RED criteria. The model's performance was consistent in the 2 validation sets.

CONCLUSIONS

The prehospital triage model is promising for predicting severe trauma and achieving an undertriage rate of <10%. Moreover, machine learning enhances the performance of field triage guidelines.

Ready to launch: a cross-sectional study of field trauma triage and air-ambulance policies across Canada

PURPOSE

This study aimed to understand current prehospital trauma air-ambulance policies and triage guidelines across Canada. The research question centered on understanding the guidelines used by provinces and territories and identifying potential regional variations in air-ambulance triage.

METHODS

We conducted a cross-sectional survey from November 2022 to May 2023, involving trauma leaders from Canada's 13 provinces and territories. Participants were identified via the Trauma Association of Canada and professional networks. The survey, developed with expert input and pilot tested for clarity, focused on prehospital trauma-triage guidelines, level of adoption of Center for Disease Control and Prevention (CDC) triage guidelines, and auto-launch air-ambulance policies. Data were collected using an 18-item electronic survey. Potential response bias was considered, and confidentiality was maintained. A cross-sectional qualitative analysis was used to evaluate the guidelines' adoption and variations, with responses compared across regions.

RESULTS

The analysis revealed a nationwide adoption (11 of 11 respondents) of the CDC guidelines, indicating a standardized approach to patient transportation. Notably, many provinces and territories (5 of 11) endorse auto-launch protocols for air ambulances in specific scenarios. These policies offer advantages in geographically vast regions weighed against the cost of over-triage and inefficient resource allocation. Each province and territory tailors its approach based on factors such as geographic areas served, and available resources.

CONCLUSION

This study provides a snapshot of the current state of prehospital trauma-triage guidelines in Canada. With some differences in nomenclature, Canadian provinces and territories widely apply the CDC guidelines to serve their populations. There is some regional variation on how transport is initiated within their borders. The findings underscore the delicate balance required for optimizing air-ambulance policies, considering factors such as timely access, resource allocation, and the local application of guidelines.

Effectiveness of a two-tiered trauma team activation system at a level I trauma center

PURPOSE

Many trauma patients who are transported to our level I trauma center have minor injuries that do not require full trauma team activation (FTTA). Thus, we implemented a two-tiered TTA system categorizing patients into red and yellow code alerts, indicating FTTA and Limited TTA (LTTA) requirements, respectively. This study aimed to assess the effectiveness of this triage tool by evaluating its diagnostic parameters (sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), undertriage and overtriage) and comparing injury severity between the two groups.

METHODS

A retrospective cohort study of patients admitted to a Level I trauma center. Characteristics compared between the red and yellow code groups included demographics, injury severity, treatments, and hospital length of stay (LOS). Calculating the diagnostic parameters was based on Injury Severity Score (ISS) and the need for life-saving surgery or procedures.

RESULTS

Significant differences in injury severity indicators were observed between the two groups. Patients in the red code group had a higher ISS and New Injury Severity Score (NISS), a lower Glasgow Coma Score (GCS), Revised Trauma Score (RTS), and probability of survival. They had a longer hospital LOS, a higher Intensive Care Unit (ICU) admission rate and required more emergency operations. The Sensitivity of the triage tool was 85.2%, specificity was 55.6%, PPV was 74.2%, NPV was 71.5%, undertriage was 14.7%, and overtriage was 25.7%.

CONCLUSION

The two-tiered TTA system effectively distinguish between patients with major trauma who need FTTA and patients with minor trauma who can be managed by LTTA.

Feasibility and diagnostic accuracy of fast whole-body MRI in slightly to moderately injured trauma patients

OBJECTIVES

To determine the feasibility and diagnostic accuracy of fast whole-body magnetic resonance imaging (WB-MRI) compared to whole-body computed tomography (WB-CT) in detecting injuries of slightly to moderately injured trauma patients.

MATERIALS AND METHODS

In a prospective single-center approach, trauma patients from convenience sampling with an expected Abbreviated Injury Scale (AIS) score ≤ 3 at admission, received an indicated contrast-enhanced WB-CT (reference standard) and a plain WB-MRI (index test) voluntarily up to five days after trauma. Two radiologists, blinded to the WB-CT findings, evaluated the absence or presence of injuries with WB-MRI in four body regions: head, torso, axial skeleton, and upper extremity. Diagnostic accuracy was determined using sensitivity, specificity, positive predictive value, and negative predictive value by body region.

RESULTS

Between June 2019 and July 2021, 40 patients were assessed for eligibility of whom 35 (median age (interquartile range): 50 (32.5) years; 26 men) received WB-MRI. Of 140 body regions (35 patients × 4 regions), 31 true positive, 6 false positive, 94 true negative, and 9 false negative findings were documented with WB-MRI. Thus, plain WB-MRI achieved a total sensitivity of 77.5% (95%-confidence interval (CI): (61.6-89.2%)), specificity of 94% (95%-CI: (87.4-97.8%)), and diagnostic accuracy of 89.3% (95%-CI: (82.9-93.9%)). Across the four regions sensitivity and specificity varied: head (66.7%/93.1%), torso (62.5%/96.3%), axial skeleton (91.3%/75%), upper extremity (33.3%/100%). Both radiologists showed substantial agreement on the WB-MRI reading (Cohen's Kappa: 0.66, 95%-CI: (0.51-0.81)).

CONCLUSION

Regarding injury detection, WB-MRI is feasible in slightly to moderately injured trauma patients, especially in the axial skeleton.

CLINICAL RELEVANCE STATEMENT

Besides offering a radiation-free approach, whole-body MRI detects injuries almost identically to whole-body CT in slightly to moderately injured trauma patients, who comprise a relevant share of all trauma patients.

KEY POINTS

Whole-body MRI could offer radiation-free injury detection in slightly to moderately injured trauma patients. Whole-body MRI detected injuries almost identically compared to whole-body CT in this population. Whole-body MRI could be a radiation-free approach for slightly to moderately injured young trauma patients.

Prospective validation of a hospital triage predictive model to decrease undertriage: an EAST multicenter study

Background

Tiered trauma team activation (TTA) allows systems to optimally allocate resources to an injured patient. Target undertriage and overtriage rates of <5% and <35% are difficult for centers to achieve, and performance variability exists. The objective of this study was to optimize and externally validate a previously developed hospital trauma triage prediction model to predict the need for emergent intervention in 6 hours (NEI-6), an indicator of need for a full TTA.

Methods

The model was previously developed and internally validated using data from 31 US trauma centers. Data were collected prospectively at five sites using a mobile application which hosted the NEI-6 model. A weighted multiple logistic regression model was used to retrain and optimize the model using the original data set and a portion of data from one of the prospective sites. The remaining data from the five sites were designated for external validation. The area under the receiver operating characteristic curve (AUROC) and the area under the precision-recall curve (AUPRC) were used to assess the validation cohort. Subanalyses were performed for age, race, and mechanism of injury.

Results

14 421 patients were included in the training data set and 2476 patients in the external validation data set across five sites. On validation, the model had an overall undertriage rate of 9.1% and overtriage rate of 53.7%, with an AUROC of 0.80 and an AUPRC of 0.63. Blunt injury had an undertriage rate of 8.8%, whereas penetrating injury had 31.2%. For those aged ≥65, the undertriage rate was 8.4%, and for Black or African American patients the undertriage rate was 7.7%.

Conclusion

The optimized and externally validated NEI-6 model approaches the recommended undertriage and overtriage rates while significantly reducing variability of TTA across centers for blunt trauma patients. The model performs well for populations that traditionally have high rates of undertriage.

Level of evidence

2.

State of the art of trauma teams in Italy: A nationwide study

Trauma teams play a vital role in providing prompt and specialized care to trauma patients. This study aims to provide a comprehensive description of the presence and organization of trauma teams in Italy. A nationwide cross-sectional epidemiological study was conducted between July and October 2022, involving interviews with 137 designated trauma centers. Centers were stratified based on level: higher specialized trauma centers (CTS), intermediate level trauma centers (CTZ + N) and district general hospital with trauma capacity (CTZ). A standardized structured interview questionnaire was used to gather information on hospital characteristics, trauma team prevalence, activation pathways, structure, components, leadership, education, and governance. Descriptive statistics were used for analysis. Results showed that 53 % of the centers had a formally defined trauma team, with higher percentages in CTS (73 %) compared to CTZ + N (49 %) and CTZ (39 %). The trauma team activation pathway varied among centers, with pre-alerts predominantly received from emergency medical services. The study also highlighted the lack of formally defined massive transfusion protocols in many centers. The composition of trauma teams typically included airway and procedure doctors, nurses, and healthcare assistants. Trauma team leadership was predetermined in 59 % of the centers, with anesthesiologists/intensive care physicians often assuming this role. The study revealed gaps in trauma team education and governance, with a lack of specific training for trauma team leaders and low utilization of simulation-based training. These findings emphasize the need for improvements in trauma management education, governance, and the formalization of trauma teams. This study provides valuable insights that can guide discussions and interventions aimed at enhancing trauma care at both local and national levels in Italy.

Cutoff of the reverse shock index multiplied by the Glasgow coma scale for predicting in-hospital mortality in adult patients with trauma: a retrospective cohort study

BACKGROUND

Early identification of patients at risk of potential death and timely transfer to appropriate healthcare facilities are critical for reducing the number of preventable trauma deaths. This study aimed to establish a cutoff value to predict in-hospital mortality using the reverse shock index multiplied by the Glasgow Coma Scale (rSIG).

METHODS

This multicenter retrospective cohort study used data from 23 emergency departments in South Korea between January 2011 and December 2020. The outcome variable was the in-hospital mortality. The relationship between rSIG and in-hospital mortality was plotted using the shape-restricted regression spline method. To set a cutoff for rSIG, we found the point on the curve where mortality started to increase and the point where the slope of the mortality curve changed the most. We also calculated the cutoff value for rSIG using Youden's index.

RESULTS

A total of 318,506 adult patients with trauma were included. The shape-restricted regression spline curve showed that in-hospital mortality began to increase when the rSIG value was less than 18.86, and the slope of the graph increased the most at 12.57. The cutoff of 16.5, calculated using Youden's index, was closest to the target under-triage and over-triage rates, as suggested by the American College of Surgeons, when applied to patients with an rSIG of 20 or less. In addition, in patients with traumatic brain injury, when the rSIG value was over 25, in-hospital mortality tended to increase as the rSIG value increased.

CONCLUSIONS

We propose an rSIG cutoff value of 16.5 as a predictor of in-hospital mortality in adult patients with trauma. However, in patients with traumatic brain injury, a high rSIG is also associated with in-hospital mortality. Appropriate cutoffs should be established for this group in the future.

Review article: Pre-hospital trauma guidelines and access to lifesaving interventions in Australia and Aotearoa/New Zealand

The centralisation of trauma services in western countries has led to an improvement in patient outcomes. Effective trauma systems include a pre-hospital trauma system. Delivery of high-level pre-hospital trauma care must include identification of potential major trauma patients, access and correct application of lifesaving interventions (LSIs) and timely transport to definitive care. Globally, many nations endorse nationwide pre-hospital major trauma triage guidelines, to ensure a universal approach to patient care. This paper examined clinical guidelines from all 10 EMS in Australia and Aotearoa/New Zealand. All relevant trauma guidelines were included, and key information was extracted. Authors compared major trauma triage criteria, all LSI included in guidelines, and guidelines for transport to definitive care. The identification of major trauma patients varied between all 10 EMS, with no universal criteria. The most common approach to trauma triage included a three-step assessment process: physiological criteria, identified injuries and mechanism of injury. Disparity between physiological criteria, injuries and mechanism was found when comparing guidelines. All 10 EMS had fundamental LSI included in their trauma guidelines. Fundamental LSI included haemorrhage control (arterial tourniquets, pelvic binders), non-invasive airway management (face mask ventilation, supraglottic airway devices) and pleural wall needle decompression. Variation in more advanced LSI was evident between EMS. Optimising trauma triage guidelines is an important aspect of a robust and evidence driven trauma system. The lack of consensus in trauma triage identified in the present study makes benchmarking and comparison of trauma systems difficult.

Evaluating the impact of pre-hospital trauma team activation criteria

BACKGROUND

Little evidence exists studying the benefits of pre-hospital trauma team activation. Our study measured the impact of pre-hospital trauma team activation on 24-h survival. Our secondary objectives assessed the effects of pre-hospital trauma team activation on time to emergency procedure, computed tomography, blood transfusion, and critical administration threshold, as well as emergency department length of stay.

METHODS

We conducted a 40-month health records review on all trauma team activations at The Ottawa Hospital, a Level 1 Trauma Center. Outcomes were compared between pre-hospital and in-hospital trauma team activations. We used logistic and linear regression models to assess outcomes, while controlling for injury severity score, age, systolic blood pressure, and anti-coagulation use. A P value < 0.05 was considered statistically significant. A sensitivity analysis was also used to validate the primary outcome results.

RESULTS

Of the 1013 trauma team activations occurring during the study period, 762 patients were included. The mean age (41.3 vs. 43.8) and percentage of males (79.4% vs. 77.5%) for pre-hospital activations were similar to their counterparts. Pre-hospital activations did not have a statistically significant effect on 24-h mortality (14.4% vs. 4.5%; P = 0.30). However, pre-hospital activations did demonstrate a statistically significant reduction in time (minutes) to emergency procedure (18.0 vs. 27.0; P < 0.001), computed tomography (37.0 vs 42.0; P = 0.009), and blood transfusion (14.0 vs. 28.0; P < 0.001), as well as emergency department length of stay (101.0 vs. 171.0; P < 0.001).

CONCLUSION

When controlling for key covariates, pre-hospital trauma team activation did not have a significant effect on 24-h mortality, but did result in a significant reduction in time to emergency procedure, computed tomography, and blood transfusion, as well as emergency department length of stay. Our study demonstrates that pre-hospital trauma team activation can expedite patient intervention and disposition.

Pediatric vs Adult or Mixed Trauma Centers in Children Admitted to Hospitals Following Trauma: A Systematic Review and Meta-Analysis

Importance

Adult trauma centers (ATCs) have been shown to decrease injury mortality and morbidity in major trauma, but a synthesis of evidence for pediatric trauma centers (PTCs) is lacking.

Objective

To assess the effectiveness of PTCs compared with ATCs, combined trauma centers (CTCs), or nondesignated hospitals in reducing mortality and morbidity among children admitted to hospitals following trauma.

Data Sources

MEDLINE, Embase, and Web of Science through March 2023.

Study Selection

Studies comparing PTCs with ATCs, CTCs, or nondesignated hospitals for pediatric trauma populations (aged ≤19 years).

Data Extraction and Synthesis

This systematic review and meta-analysis was performed following the Preferred Reporting Items for Systematic Review and Meta-analysis and Meta-analysis of Observational Studies in Epidemiology guidelines. Pairs of reviewers independently extracted data and evaluated risk of bias using the Risk of Bias in Nonrandomized Studies of Interventions tool. A meta-analysis was conducted if more than 2 studies evaluated the same intervention-comparator-outcome and controlled minimally for age and injury severity. Subgroup analyses were planned for age, injury type and severity, trauma center designation level and verification body, country, and year of conduct. Grading of Recommendations Assessment, Development, and Evaluation (GRADE) was used to assess certainty of evidence.

Main Outcome(s) and Measure(s)

Primary outcomes were mortality, complications, functional status, discharge destination, and quality of life. Secondary outcomes were resource use and processes of care, including computed tomography (CT) and operative management of blunt solid organ injury (SOI).

Results

A total of 56 studies with 286 051 participants were included overall, and 34 were included in the meta-analysis. When compared with ATCs, PTCs were associated with a 41% lower risk of mortality (OR, 0.59; 95% CI, 0.46-0.76), a 52% lower risk of CT use (OR, 0.48; 95% CI, 0.26-0.89) and a 64% lower risk of operative management for blunt SOI (OR, 0.36; 95% CI, 0.23-0.57). The OR for complications was 0.80 (95% CI, 0.41-1.56). There was no association for mortality for older children (OR, 0.71; 95% CI, 0.47-1.06), and the association was closer to the null when PTCs were compared with CTCs (OR, 0.73; 95% CI, 0.53-0.99). Results remained similar for other subgroup analyses. GRADE certainty of evidence was very low for all outcomes.

Conclusions and Relevance

In this systematic review and meta-analysis, results suggested that PTCs were associated with lower odds of mortality, CT use, and operative management for SOI than ATCs for children admitted to hospitals following trauma, but certainty of evidence was very low. Future studies should strive to address selection and confounding biases.

Adherence to the transfer recommendations of the German Trauma Society in severely injured children: a retrospective study from the TraumaRegister DGU

Particularly for pediatric trauma patients, it is of utmost importance that the right patient be treated in the right place at the right time. While unnecessary interhospital transfers must be avoided, the decision against transfer should not lead to higher complication rates in trauma centers without added pediatric qualifications. We therefore identified independent predictive factors for an early transfer of severely injured patients and compared these factors with the current transfer recommendations of the German Trauma Society. Additionally, the quality of the self-assessment based on the mortality of children who were not transferred was evaluated. A national dataset from the TraumaRegister DGU® was used to retrospectively identify factors for an early interhospital transfer (< 48 h) to a superordinate trauma center. Severely injured pediatric patients (age < 16 years) admitted between 2010 and 2019 were included in this analysis. Adjusted odds ratios (OR) with 95% confidence intervals (CI) for early transfer were calculated from a multivariable model. Prognostic factors for hospital mortality in non-transferred patients were also analyzed. In total, 6069 severely injured children were included. Of these, 65.2% were admitted to a Level I trauma center, whereas 27.7% and 7.1% were admitted to Level II and III centers, respectively. After the initial evaluation in the emergency department, 25.5% and 50.1% of children primarily admitted to a Level II or III trauma center, respectively, were transferred early. Statistically significant predictors of an early transfer were: Serious traumatic brain injury (OR 1.76, 95% CI 1.28-2.43), Injury severity score (ISS) ≥ 16 points (ISS 16-24: OR 2.06, 95% CI 1.59-2.66; ISS 25-33: OR 3.0, 95% CI 2.08-4.31; ISS 34-75: OR 5.42, 95% CI 3.0-9.81, reference category: ISS 9-15), age < 10 years (age 0-1: OR 1.91, 95% CI 1.34-2.71; age 2-5: 2.04, 95% CI 1.50-2.78; age 6-9: 1.62, 95% CI 1.23-2.14; reference category: age 10-15). The most important independent factor for mortality in non-transferred patients was age < 10 years (age 0-1: 5.35, 95% CI 3.25-8.81; age 2-5: 2.46, 95% CI 1.50-4.04; age 6-9: OR 1.7, 95% CI 1.05-2.75; reference category: age 10-15). Knowing the independent predictors for an early transfer, such as a young patient's age, a high injury severity, serious traumatic brain injury (TBI), may improve the choice of the appropriate trauma center. This may guide the rapid decision for an early interhospital transfer. There is still a lack of outcome data on children with early interhospital transfers in Germany, who are the most vulnerable group.

Blood coagulation test abnormalities in trauma patients detected by sonorheometry: a retrospective cohort study

Background

Traumatic hemorrhage guidelines include point-of-care viscoelastic tests as a standard of care. Quantra (Hemosonics) is a device based on sonic estimation of elasticity via resonance (SEER) sonorheometry to assess whole blood clot formation.

Objectives

Our study aimed to assess the ability of an early SEER evaluation to detect blood coagulation test abnormalities in trauma patients.

Methods

We conducted an observational retrospective cohort study with data collected at hospital admission of consecutive multiple trauma patients from September 2020 to February 2022 at a regional level 1 trauma center. We performed a receiving operator characteristic curve analysis to determine the ability of the SEER device to detect blood coagulation test abnormalities. Four values on the SEER device were analyzed: clot formation time, clot stiffness (CS), platelet contribution to CS, and fibrinogen contribution to CS.

Results

A total of 156 trauma patients were analyzed. The clot formation time value predicted an activated partial thromboplastin time ratio of >1.5 with an area under the curve (AUC) of 0.93 (95% CI, 0.86-0.99). The AUC of the CS value in detecting an international normalized ratio of prothrombin time of >1.5 was 0.87 (95% CI, 0.79-0.95). The AUC of fibrinogen contribution to CS to detect a fibrinogen concentration of <1.5 g/L was 0.87 (95% CI, 0.80-0.94). The AUC of platelet contribution to CS to detect a platelet concentration of <50 G/L was 0.99 (95% CI, 0.99-1.00).

Conclusion

Our results suggest that the SEER device may be useful for the detection of blood coagulation test abnormalities at trauma admission.

Accuracy of a Prehospital Triage Protocol in Predicting In-Hospital Mortality and Severe Trauma Cases among Older Adults

Background: Prehospital trauma triage tools are not tailored to identify severely injured older adults. Our trauma triage protocol based on a three-tier trauma severity grading system (A, B, and C) has never been studied in this population. The objective was to assess its accuracy in predicting in-hospital mortality among older adults (≥65 years) and to compare it to younger patients. Methods: A retrospective multicenter cohort study, from 2011 to 2021. Consecutive adult trauma patients managed by a mobile medical team were prospectively graded A, B, or C according to the initial seriousness of their injuries. Accuracy was evaluated using sensitivity, specificity, positive and negative predictive values, and positive and negative likelihood ratios. Results: 8888 patients were included (14.1% were ≥65 years). Overall, 10.1% were labeled Grade A (15.2% vs. 9.3% among older and younger adults, respectively), 21.9% Grade B (27.9% vs. 20.9%), and 68.0% Grade C (56.9% vs. 69.8%). In-hospital mortality was 7.1% and was significantly higher among older adults regardless of severity grade. Grade A showed lower sensitivity (50.5 (43.7; 57.2) vs. 74.6 (69.8; 79.1), p < 0.0001) for predicting mortality among older adults compared to their younger counterparts. Similarly, Grade B was associated with lower sensitivity (89.5 (84.7; 93.3) vs. 97.2 (94.8; 98.60), p = 0.0003) and specificity (69.4 (66.3; 72.4) vs. 74.6 (73.6; 75.7], p = 0.001) among older adults. Conclusions: Our prehospital trauma triage protocol offers high sensitivity for predicting in-hospital mortality including older adults.

Prehospital Tranexamic Acid in Major Pediatric Trauma Within a Physician-Led Emergency Medical Services System: A Multicenter Retrospective Study

OBJECTIVES

Describe prehospital tranexamic acid (TXA) use and appropriateness within a major trauma pediatric population, and identify the factors associated with its use.

DESIGN

Multicenter, retrospective study, 2014-2020.

SETTING

Data were extracted from a multicenter French trauma registry including nine trauma centers within a physician-led prehospital emergency medical services (EMS) system.

PATIENTS

Patients less than 18 years old were included. Those who did not receive prehospital intervention by a mobile medical team and those with missing data on TXA administration were excluded.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Nine-hundred thirty-four patients (median [interquartile range] age: 14 yr [9-16 yr]) were included, and 68.6% n = 639) were male. Most patients were involved in a road collision (70.2%, n = 656) and suffered a blunt trauma (96.5%; n = 900). Patients receiving TXA (36.6%; n = 342) were older (15 [13-17] vs 12 yr [6-16 yr]) compared with those who did not. Patient severity was higher in the TXA group (Injury Severity Score 14 [9-25] vs 6 [2-13]; p < 0.001). The median dosage was 16 mg/kg (13-19 mg/kg). TXA administration was found in 51.8% cases ( n = 256) among patients with criteria for appropriate use. Conversely, 32.4% of patients ( n = 11) with an isolated severe traumatic brain injury (TBI) also received TXA. Age (odds ratio [OR], 1.2; 95% CI, 1.1-1.2), A and B prehospital severity grade (OR, 7.1; 95% CI, 4.1-12.3 and OR, 4.5; 95% CI, 2.9-6.9 respectively), and year of inclusion (OR, 1.2; 95% CI, 1.1-1.3) were associated with prehospital TXA administration.

CONCLUSIONS

In our physician-led prehospital EMS system, TXA is used in a third of severely injured children despite the lack of high-level of evidence. Only half of the population with greater than or equal to one criteria for appropriate TXA use received it. Conversely, TXA was administered in a third of isolated severe TBI. Further research is warranted to clarify TXA indications and to evaluate its impact on mortality and its safety profile to oversee its prescription.

Traumatic brain injury: progress and challenges in prevention, clinical care, and research

Traumatic brain injury (TBI) has the highest incidence of all common neurological disorders, and poses a substantial public health burden. TBI is increasingly documented not only as an acute condition but also as a chronic disease with long-term consequences, including an increased risk of late-onset neurodegeneration. The first Lancet Neurology Commission on TBI, published in 2017, called for a concerted effort to tackle the global health problem posed by TBI. Since then, funding agencies have supported research both in high-income countries (HICs) and in low-income and middle-income countries (LMICs). In November 2020, the World Health Assembly, the decision-making body of WHO, passed resolution WHA73.10 for global actions on epilepsy and other neurological disorders, and WHO launched the Decade for Action on Road Safety plan in 2021. New knowledge has been generated by large observational studies, including those conducted under the umbrella of the International Traumatic Brain Injury Research (InTBIR) initiative, established as a collaboration of funding agencies in 2011. InTBIR has also provided a huge stimulus to collaborative research in TBI and has facilitated participation of global partners. The return on investment has been high, but many needs of patients with TBI remain unaddressed. This update to the 2017 Commission presents advances and discusses persisting and new challenges in prevention, clinical care, and research.

In LMICs, the occurrence of TBI is driven by road traffic incidents, often involving vulnerable road users such as motorcyclists and pedestrians. In HICs, most TBI is caused by falls, particularly in older people (aged ≥65 years), who often have comorbidities. Risk factors such as frailty and alcohol misuse provide opportunities for targeted prevention actions. Little evidence exists to inform treatment of older patients, who have been commonly excluded from past clinical trials—consequently, appropriate evidence is urgently required. Although increasing age is associated with worse outcomes from TBI, age should not dictate limitations in therapy. However, patients injured by low-energy falls (who are mostly older people) are about 50% less likely to receive critical care or emergency interventions, compared with those injured by high-energy mechanisms, such as road traffic incidents.

Mild TBI, defined as a Glasgow Coma sum score of 13–15, comprises most of the TBI cases (over 90%) presenting to hospital. Around 50% of adult patients with mild TBI presenting to hospital do not recover to pre-TBI levels of health by 6 months after their injury. Fewer than 10% of patients discharged after presenting to an emergency department for TBI in Europe currently receive follow-up. Structured follow-up after mild TBI should be considered good practice, and urgent research is needed to identify which patients with mild TBI are at risk for incomplete recovery.

The selection of patients for CT is an important triage decision in mild TBI since it allows early identification of lesions that can trigger hospital admission or life-saving surgery. Current decision making for deciding on CT is inefficient, with 90–95% of scanned patients showing no intracranial injury but being subjected to radiation risks. InTBIR studies have shown that measurement of blood-based biomarkers adds value to previously proposed clinical decision rules, holding the potential to improve efficiency while reducing radiation exposure. Increased concentrations of biomarkers in the blood of patients with a normal presentation CT scan suggest structural brain damage, which is seen on MR scanning in up to 30% of patients with mild TBI. Advanced MRI, including diffusion tensor imaging and volumetric analyses, can identify additional injuries not detectable by visual inspection of standard clinical MR images. Thus, the absence of CT abnormalities does not exclude structural damage—an observation relevant to litigation procedures, to management of mild TBI, and when CT scans are insufficient to explain the severity of the clinical condition.

Although blood-based protein biomarkers have been shown to have important roles in the evaluation of TBI, most available assays are for research use only. To date, there is only one vendor of such assays with regulatory clearance in Europe and the USA with an indication to rule out the need for CT imaging for patients with suspected TBI. Regulatory clearance is provided for a combination of biomarkers, although evidence is accumulating that a single biomarker can perform as well as a combination. Additional biomarkers and more clinical-use platforms are on the horizon, but cross-platform harmonisation of results is needed. Health-care efficiency would benefit from diversity in providers.

In the intensive care setting, automated analysis of blood pressure and intracranial pressure with calculation of derived parameters can help individualise management of TBI. Interest in the identification of subgroups of patients who might benefit more from some specific therapeutic approaches than others represents a welcome shift towards precision medicine. Comparative-effectiveness research to identify best practice has delivered on expectations for providing evidence in support of best practices, both in adult and paediatric patients with TBI.

Progress has also been made in improving outcome assessment after TBI. Key instruments have been translated into up to 20 languages and linguistically validated, and are now internationally available for clinical and research use. TBI affects multiple domains of functioning, and outcomes are affected by personal characteristics and life-course events, consistent with a multifactorial bio-psycho-socio-ecological model of TBI, as presented in the US National Academies of Sciences, Engineering, and Medicine (NASEM) 2022 report. Multidimensional assessment is desirable and might be best based on measurement of global functional impairment. More work is required to develop and implement recommendations for multidimensional assessment. Prediction of outcome is relevant to patients and their families, and can facilitate the benchmarking of quality of care. InTBIR studies have identified new building blocks (eg, blood biomarkers and quantitative CT analysis) to refine existing prognostic models. Further improvement in prognostication could come from MRI, genetics, and the integration of dynamic changes in patient status after presentation.

Neurotrauma researchers traditionally seek translation of their research findings through publications, clinical guidelines, and industry collaborations. However, to effectively impact clinical care and outcome, interactions are also needed with research funders, regulators, and policy makers, and partnership with patient organisations. Such interactions are increasingly taking place, with exemplars including interactions with the All Party Parliamentary Group on Acquired Brain Injury in the UK, the production of the NASEM report in the USA, and interactions with the US Food and Drug Administration. More interactions should be encouraged, and future discussions with regulators should include debates around consent from patients with acute mental incapacity and data sharing. Data sharing is strongly advocated by funding agencies. From January 2023, the US National Institutes of Health will require upload of research data into public repositories, but the EU requires data controllers to safeguard data security and privacy regulation. The tension between open data-sharing and adherence to privacy regulation could be resolved by cross-dataset analyses on federated platforms, with the data remaining at their original safe location. Tools already exist for conventional statistical analyses on federated platforms, however federated machine learning requires further development. Support for further development of federated platforms, and neuroinformatics more generally, should be a priority.

This update to the 2017 Commission presents new insights and challenges across a range of topics around TBI: epidemiology and prevention (section 1 ); system of care (section 2 ); clinical management (section 3 ); characterisation of TBI (section 4 ); outcome assessment (section 5 ); prognosis (Section 6 ); and new directions for acquiring and implementing evidence (section 7 ). Table 1 summarises key messages from this Commission and proposes recommendations for the way forward to advance research and clinical management of TBI.

Prehospital triage tools in major trauma: a critical appraisal of a systematic review

Effective triage is critical to ensure patients suffering major trauma are identified and access a pathway to definitive major trauma care, typically provided in a major trauma centre as part of an established major trauma system. The pre-hospital triage of trauma patients often relies upon the use of major trauma triage tools; this commentary critically appraises a recent systematic review which sought to evaluate and compare the accuracy of pre-hospital triage tools for major trauma.

Machine Learning-Based Text Analysis to Predict Severely Injured Patients in Emergency Medical Dispatch: Model Development and Validation

Background

Early recognition of severely injured patients in prehospital settings is of paramount importance for timely treatment and transportation of patients to further treatment facilities. The dispatching accuracy has seldom been addressed in previous studies.

Objective

In this study, we aimed to build a machine learning–based model through text mining of emergency calls for the automated identification of severely injured patients after a road accident.

Methods

Audio recordings of road accidents in Taipei City, Taiwan, in 2018 were obtained and randomly sampled. Data on call transfers or non-Mandarin speeches were excluded. To predict cases of severe trauma identified on-site by emergency medical technicians, all included cases were evaluated by both humans (6 dispatchers) and a machine learning model, that is, a prehospital-activated major trauma (PAMT) model. The PAMT model was developed using term frequency–inverse document frequency, rule-based classification, and a Bernoulli naïve Bayes classifier. Repeated random subsampling cross-validation was applied to evaluate the robustness of the model. The prediction performance of dispatchers and the PAMT model, in severe cases, was compared. Performance was indicated by sensitivity, specificity, positive predictive value, negative predictive value, and accuracy.

Results

Although the mean sensitivity and negative predictive value obtained by the PAMT model were higher than those of dispatchers, they obtained higher mean specificity, positive predictive value, and accuracy. The mean accuracy of the PAMT model, from certainty level 0 (lowest certainty) to level 6 (highest certainty), was higher except for levels 5 and 6. The overall performances of the dispatchers and the PAMT model were similar; however, the PAMT model had higher accuracy in cases where the dispatchers were less certain of their judgments.

Conclusions

A machine learning–based model, called the PAMT model, was developed to predict severe road accident trauma. The results of our study suggest that the accuracy of the PAMT model is not superior to that of the participating dispatchers; however, it may assist dispatchers when they lack confidence while making a judgment.

A prospective study comparing two methods of pre-hospital triage for trauma

We conducted a prospective study comparing two different pre-hospital triage tools for trauma: the American College of Surgeons Committee on Trauma (ACS-COT) field triage decision scheme and the TRENAU score. The main objective was to evaluate which triage tool was more appropriate in the setting of Lombardy's trauma system. Data were collected from the population of trauma patients admitted to Niguarda hospital in Milan from January to June 2021. RStudio and Excel were used for data analysis. For each triage tool performance measures, Receiver Operating Characteristics (ROC) curves, and overtriage and undertriage rates were obtained. A total of 1439 injured patients admitted through 118 pre-hospital Emergency Medical Services (EMS) were included in the study. The ACS-COT triage tool showed a good accuracy but an excessive overtriage rate (59%). The TRENAU triage tool had a moderately good accuracy and a low overtriage rate (23%) while maintaining an acceptable undertriage rate (3.9%). The TRENAU triage tool proved to be efficient in optimizing the use of resources dedicated to trauma care while resulting safe for the injured patient. In a modern trauma system such as Lombardy's it would be more appropriate to adopt the TRENAU score over the ACS-COT field triage decision scheme.