Identifying patients with time-sensitive injuries: Association of mortality with increasing prehospital time

Prehospital time and mortality in pediatric trauma

PURPOSE

The "Golden Hour" of transportation to a hospital has long been accepted as a central principal of trauma care. However, this has not been studied in pediatric populations. We assessed for non-linearity of the relationship between prehospital time and mortality in pediatric trauma patients, redefining the threshold at which reducing this time led to more favorable outcomes.

METHODS

We performed an analysis of the 2017-2018 American College of Surgeons Trauma Quality Improvement Program, including trauma patients age < 18 years. We examined the association between prehospital time and odds of in-hospital mortality using linear, polynomial, and restricted cubic spline (RCS) models, ultimately selecting the non-linear RCS model as the best fit.

RESULTS

60,670 patients were included in the study, of whom 1525 died and 3074 experienced complications. Prolonged prehospital time was associated with lower mortality and fewer complications. Both models demonstrated that mortality risk was lowest at 45-60 min, after which time was no longer associated with reduced probability of mortality.

CONCLUSIONS

The demonstration of a non-linear relationship between pre-hospital time and patient mortality is a novel finding. We highlight the need to improve prehospital treatment and access to pediatric trauma centers while aiming for hospital transportation within 45 min.

Outcomes by time-to-OR for penetrating abdominal trauma patients

INTRODUCTION

Time-To-OR is a critical process measure for trauma performance. However, this measure has not consistently demonstrated improvement in outcome.

STUDY DESIGN

Using TQIP, we identified facilities by 75th percentile time-to-OR to categorize slow, average, and fast hospitals. Using a GEE model, we calculated odds of mortality for all penetrating abdominal trauma patients, firearm injuries only, and patients with major complication by facility speed. We additionally estimated odds of mortality at the patient level.

RESULTS

Odds of mortality for patients at slow facilities was 1.095; 95% CI: 0.746, 1.608; p = 0.64 compared to average. Fast facility OR = 0.941; 95% CI: 0.780, 1.133; p = 0.52. At the patient-level each additional minute of time-to-OR was associated with 1.5% decreased odds of in-hospital mortality (OR 0.985; 95% CI:0.981, 0.989; p < 0.001). For firearm-only patients, facility speed was not associated with odds of in-hospital mortality (p-value = 0.61). Person-level time-to-OR was associated with 1.8% decreased odds of in-hospital mortality (OR 0.982; 95% CI: 0.977, 0.987; p < 0.001) with each additional minute of time-to-OR. Similarly, failure-to-rescue analysis showed no difference in in-hospital mortality at the patient level (p = 0.62) and 0.4% decreased odds of in-hospital mortality with each additional minute of time-to-OR at the patient level (OR 0.996; 95% CI: 0.993, 0.999; p = 0.004).

CONCLUSION

Despite the use of time-to-OR as a metric of trauma performance, there is little evidence for improvement in mortality or complication rate with improved time-to-OR at the facility or patient level. Performance metrics for trauma should be developed that more appropriately approximate patient outcome.

Missingness matters: a secondary analysis of thromboelastography measurements from a recent prehospital randomized tranexamic acid clinical trial

Background

Tranexamic acid (TXA) has been hypothesized to mitigate coagulopathy in patients after traumatic injury. Despite previous prehospital clinical trials demonstrating a TXA survival benefit, none have demonstrated correlated changes in thromboelastography (TEG) parameters. We sought to analyze if missing TEG data contributed to this paucity of findings.

Methods

We performed a secondary analysis of the Study of Tranexamic Acid During Air Medical and Ground Prehospital Transport Trial. We compared patients that received TEG (YES-TEG) and patients unable to be sampled (NO-TEG) to analyze subgroups in which to investigate TEG differences. TEG parameter differences across TXA intervention arms were assessed within subgroups disproportionately present in the NO-TEG relative to the YES-TEG cohort. Generalized linear models controlling for potential confounders were applied to findings with p<0.10 on univariate analysis.

Results

NO-TEG patients had lower prehospital systolic blood pressure (SBP) (100 (78, 140) vs 125 (88, 147), p<0.01), lower prehospital Glascow Coma Score (14 (3, 15) vs 15 (12, 15), p<0.01), greater rates of prehospital intubation (39.4% vs 24.4%, p<0.01) and greater mortality at 30 days (36.4% vs 6.8%, p<0.01). NO-TEG patients had a greater international normalized ratio relative to the YES-TEG subgroup (1.2 (1.1, 1.5) vs 1.1 (1.0, 1.2), p=0.04). Within a severe prehospital shock cohort (SBP<70), TXA was associated with a significant decrease in clot lysis at 30 min on multivariate analysis (β=-27.6, 95% CI (-51.3 to -3.9), p=0.02).

Conclusions

Missing data, due to the logistical challenges of sampling certain severely injured patients, may be associated with a lack of TEG parameter changes on TXA administration in the primary analysis. Previous demonstration of TXA's survival benefit in patients with severe prehospital shock in tandem with the current findings supports the notion that TXA acts at least partially by improving clot integrity.

Level of evidence

Level II.

Dynamic ambulance relocation: a scoping review

OBJECTIVES

Dynamic ambulance relocation means that the operators at a dispatch centre place an ambulance in a temporary location, with the goal of optimising coverage and response times in future medical emergencies. This study aimed to scope the current research on dynamic ambulance relocation.

DESIGN

A scoping review was conducted using a structured search in PubMed, Scopus and Web of Science. In total, 21 papers were included.

RESULTS

Most papers described research with experimental designs involving the use of mathematical models to calculate the optimal use and temporary relocations of ambulances. The models relied on several variables, including distances, locations of hospitals, demographic-geological data, estimation of new emergencies, emergency medical services (EMSs) working hours and other data. Some studies used historic ambulance dispatching data to develop models. Only one study reported a prospective, real-time evaluation of the models and the development of technical systems. No study reported on either positive or negative patient outcomes or real-life chain effects from the dynamic relocation of ambulances.

CONCLUSIONS

Current knowledge on dynamic relocation of ambulances is dominated by mathematical and technical support data that have calculated optimal locations of ambulance services based on response times and not patient outcomes. Conversely, knowledge of how patient outcomes and the working environment are affected by dynamic ambulance dispatching is lacking. This review has highlighted several gaps in the scientific coverage of the topic. The primary concern is the lack of studies reporting on patient outcomes, and the limited knowledge regarding several key factors, including the optimal use of ambulances in rural areas, turnaround times, domino effects and aspects of working environment for EMS personnel. Therefore, addressing these knowledge gaps is important in future studies.

Direct Trauma Center Access by Helicopter Emergency Medical Services is Associated With Improved Survival After Severe Injury

OBJECTIVE

Evaluate the association of survival with helicopter transport directly to a trauma center compared with ground transport to a non-trauma center (NTC) and subsequent transfer.

SUMMARY BACKGROUND DATA

Helicopter transport improves survival after injury. One potential mechanism is direct transport to a trauma center when the patient would otherwise be transported to an NTC for subsequent transfer.

METHODS

Scene patients 16 years and above with positive physiological or anatomic triage criteria within PTOS 2000-2017 were included. Patients transported directly to level I/II trauma centers by helicopter were compared with patients initially transported to an NTC by ground with a subsequent helicopter transfer to a level I/II trauma center. Propensity score matching was used to evaluate the association between direct helicopter transport and survival. Individual triage criteria were evaluated to identify patients most likely to benefit from direct helicopter transport.

RESULTS

In all, 36,830 patients were included. Direct helicopter transport was associated with a nearly 2-fold increase in odds of survival compared with NTC ground transport and subsequent transfer by helicopter (aOR 2.78; 95% CI 2.24-3.44, P <0.01). Triage criteria identifying patients with a survival benefit from direct helicopter transport included GCS≤13 (1.71; 1.22-2.41, P <0.01), hypotension (2.56; 1.39-4.71, P <0.01), abnormal respiratory rate (2.30; 1.36-3.89, P <0.01), paralysis (8.01; 2.03-31.69, P <0.01), hemothorax/pneumothorax (2.34; 1.36-4.05, P <0.01), and multisystem trauma (2.29; 1.08-4.84, P =0.03).

CONCLUSIONS

Direct trauma center access is a mechanism driving the survival benefit of helicopter transport. First responders should consider helicopter transport for patients meeting these criteria who would otherwise be transported to an NTC.

Prehospital times and outcomes of patients transported using an ambulance trauma transport protocol: A data linkage analysis from New South Wales Australia

INTRODUCTION

Prehospital trauma systems are designed to ensure optimal survival from critical injuries by triaging and transporting such patients to the most appropriate hospital in a timely manner.

OBJECTIVES

We sought to evaluate whether prehospital time and location (metropolitan versus non-metropolitan) were associated with 30-day mortality in a cohort of patients transported by road ambulance using a trauma transport protocol.

METHODS

Data linkage analysis of routinely collected ambulance and hospital data across all public hospitals in New South Wales (NSW). The data linkage cohort included adult patients (age ≥ 16years) transported by NSW Ambulance, where a T1 Major Trauma Transport Protocol was documented by paramedic crews and transported by road to a public hospital emergency department in NSW for two years between January 2019 and December 2020. The outcomes of interest were prehospital times (response time, scene time and transport time) and 30-day mortality due to injury.

RESULTS

9012 cases were identified who were transported to an emergency department with T1 protocol indication. Median prehospital transport times were longer in non-metropolitan road transports [n = 3,071, 98 min (71-126)] compared to metropolitan transports [n = 5,941, 65 min (53-80), p < 0.001]. There was no significant difference in 30-day mortality between the two groups (1.24% vs 1.65%, p = 0.13). In the subgroup of patients with abnormal vital signs, the only predictors of mortality were increasing age, presence of severe injury (OR 24.87, 95%CI 11.02, 56.15, p < 0.001), and arrival at a non-trauma facility (OR 3.01, 95%CI 1.26, 7.20, p < 0.05). Increasing transport times were not found to increase the odds of 30-day mortality.

DISCUSSION

In the context of an inclusive trauma system and an established prehospital major trauma protocol, increasing prehospital transport times and scene location were not associated with increased mortality.

Association of Time to Definitive Hemostasis With Mortality in Patients With Solid Organ Injuries

Introduction The Golden Hour is a term used in the trauma setting to refer to the first 60 minutes after injury. Traditionally, definitive care within this period was believed to dramatically increase a patient's survival. Though the period of 60 minutes is unlikely to represent a point of distinct inflection in survival, the effect of time to definitive care on survival remains incompletely understood. This study aims to measure the association of time to definitive hemostasis with mortality in patients with solid organ injuries as well as the effect of survival bias and a form of selection bias known as indication by severity on the relationship between time to treatment and survival. Methodology This is a retrospective cohort study using data obtained from the American College of Surgeons National Trauma Data Bank (NTDB) from the years 2017 through 2019 selecting patients treated for blunt liver, spleen, or kidney injury who required angioembolization or surgical hemostasis within six hours. A Cox proportional hazards regression was used to analyze time to death. The association of probability of death with time was examined with a multivariate logistic regression initially treating the relationship as linear and subsequently transforming time to hemostasis with restricted cubic splines to model a non-linear association with the outcome. To model survival and indication by severity bias, we created a computer-generated data set and used LOESS regressions to display curves of the simulated data. Results The multivariate Cox proportional hazards analysis shows a coefficient of negative 0.004 for minutes to hemostasis with an adjusted hazard ratio of 0.9959 showing the adjusted hazard of death slightly diminishes with each increasing minute to hemostasis. The likelihood ratio chi-square difference between the model with time to hemostasis included as a linear term versus the model with the restricted cubic spline transformation is 97.46 (p<0.0001) showing the model with restricted cubic splines is a better fit for the data. The computer-generated data simulating treatment of solid organ injury with no programmed bias displays an almost linear association of mortality with increased treatment delay. When indications by severity bias and survival bias are introduced, the risk of death decreases with time to hemostasis as in the real-world data. Conclusion Decreasing mortality with increasing delay to hemostasis in trauma patients with solid organ injury is likely due to confounding due to indication by severity and survival bias. After taking these biases into account, the association of delayed hemostasis with better survival is not likely due to the benefit of delay but rather the delay sorts patients by severity of injury with those more likely to die being treated first. These biases are extremely difficult to eliminate which limits the ability to measure the true effect of delay with retrospective data. The findings may however be of value as a predictive model to anticipate the acuity of a patient after an interval of unavoidable delay such as with a long transfer time.

Physician-staffed prehospital units: a retrospective follow-up from an urban area in Scandinavia

BACKGROUND

The aim of this study was to determine when and how rapid response vehicles (RRVs) make a difference in prehospital care by investigating the number and kinds of RRV assignment dispatches and the prehospital characteristics and interventions involved.

METHODS

This retrospective cohort study was based on data from a quality assurance system where all assignments are registered. RRV staff register every assignment directly at the site, using a smartphone, tablet, or computer. There is no mandatory information requirement or time limit for registration. The study includes data for all RRVs operating in Region Stockholm, three during daytime hours and one at night - from January 1, 2021 to December 31, 2021.

RESULTS

In 2021, RRVs in Stockholm were dispatched on 11,283 occasions, of which 3,571 (31.6%) resulted in stand-downs. In general, stand-downs were less common for older patients. The most common dispatch category was blunt trauma (1,584 or 14.0%), which accounted for the highest frequency of stand-downs (676 or 6.0%). The second most common category was cardiac arrest (1,086 or 9.6%), followed by shortness of breath (691 or 6.1%), medical not specified (N/S) (596 or 5.3%), and seizures (572 or 5.1%).

CONCLUSION

The study findings confirm that RRVs provide valuable assistance to the ambulance service in Stockholm, especially for cardiac arrest and trauma patients. In particular, RRV personnel have more advanced medical knowledge and can administer medications and perform interventions that the regular ambulance service cannot provide.

Time to early resuscitative intervention association with mortality in trauma patients at risk for hemorrhage

BACKGROUND

Hemorrhage is the leading cause of preventable death after injury. Others have shown that delays in massive transfusion cooler arrival increase mortality, while prehospital blood product resuscitation can reduce mortality. Our objective was to evaluate if time to resuscitation initiation impacts mortality.

METHODS

We combined data from the Prehospital Air Medical Plasma (PAMPer) trial in which patients received prehospital plasma or standard care and the Study of Tranexamic Acid during Air and ground Medical Prehospital transport (STAAMP) trial in which patients received prehospital tranexamic acid or placebo. We evaluated the time to early resuscitative intervention (TERI) as time from emergency medical services arrival to packed red blood cells, plasma, or tranexamic acid initiation in the field or within 90 minutes of trauma center arrival. For patients not receiving an early resuscitative intervention, the TERI was calculated based on trauma center arrival as earliest opportunity to receive a resuscitative intervention and were propensity matched to those that did to account for selection bias. Mixed-effects logistic regression assessed the association of 30-day and 24-hour mortality with TERI adjusting for confounders. We also evaluated a subgroup of only patients receiving an early resuscitative intervention as defined above.

RESULTS

Among the 1,504 propensity-matched patients, every 1-minute delay in TERI was associated with 2% increase in the odds of 30-day mortality (adjusted odds ratio [aOR], 1.020; 95% confidence interval [CI], 1.006-1.033; p < 0.01) and 1.5% increase in odds of 24-hour mortality (aOR, 1.015; 95% CI, 1.001-1.029; p = 0.03). Among the 799 patients receiving an early resuscitative intervention, every 1-minute increase in TERI was associated with a 2% increase in the odds of 30-day mortality (aOR, 1.021; 95% CI, 1.005-1.038; p = 0.01) and 24-hour mortality (aOR, 1.023; 95% CI, 1.005-1.042; p = 0.01).

CONCLUSION

Time to early resuscitative intervention is associated with morality in trauma patients with hemorrhagic shock. Bleeding patients need resuscitation initiated early, whether at the trauma center in systems with short prehospital times or in the field when prehospital time is prolonged.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level III.

Failure-to-rescue and mortality after emergent pediatric trauma laparotomy: How are the children doing?

INTRODUCTION

Emergent trauma laparotomy is associated with mortality rates of up to 40%. There is a paucity of data on the outcomes of emergent trauma laparotomies performed in the pediatric population. The aim of our study was to describe the outcomes, including mortality and FTR, among pediatric trauma patients undergoing emergent laparotomy and identify factors associated with failure-to-rescue (FTR).

METHODS

We performed a one-year (2017) retrospective cohort analysis of the American College of Surgeons Trauma Quality Improvement Program dataset. All pediatric trauma patients (age <18 years) who underwent emergent laparotomy (laparotomy performed within 2 h of admission) were included. Outcome measures were major in-hospital complications, overall mortality, and failure-to-rescue (death after in-hospital major complication). Multivariate regression analysis was performed to identify factors independently associated with failure-to-rescue.

RESULTS

Among 120,553 pediatric trauma patients, 462 underwent emergent laparotomy. Mean age was 14±4 years, 76% of patients were male, 49% were White, and 50% had a penetrating mechanism of injury. Median ISS was 25 [13-36], Abdomen AIS was 3 [2-4], Chest AIS was 2 [1-3], and Head AIS was 2 [0-5]. The median time in ED was 33 [18-69] minutes, and median time to surgery was 49 [33-77] minutes. The most common operative procedures performed were splenectomy (26%), hepatorrhaphy (17%), enterectomy (14%), gastrorrhaphy (14%), and diaphragmatic repair (14%). Only 22% of patients were treated at an ACS Pediatric Level I trauma center. The most common major in-hospital complications were cardiac (9%), followed by infectious (7%) and respiratory (5%). Overall mortality was 21%, and mortality among those presenting with hypotension was 31%. Among those who developed in-hospital major complications, the failure-to-rescue rate was 31%. On multivariate analysis, age younger than 8 years, concomitant severe head injury, and receiving packed red blood cell transfusion within the first 24 h were independently associated with failure-to-rescue.

CONCLUSIONS

Our results show that emergent trauma laparotomies performed in the pediatric population are associated with high morbidity, mortality, and failure-to-rescue rates. Quality improvement programs may use our findings to improve patient outcomes, by increasing focus on avoiding hospital complications, and further refinement of resuscitation protocols.

LEVEL OF EVIDENCE

Level IV STUDY TYPE: Epidemiologic.

The impact of prehospital time intervals on mortality in moderately and severely injured patients

BACKGROUND

Modern trauma systems and emergency medical services aim to reduce prehospital time intervals to achieve optimal outcomes. However, current literature remains inconclusive on the relationship between time to definitive treatment and mortality. The aim of this study was to investigate the association between prehospital time and mortality.

METHODS

All moderately and severely injured trauma patients (i.e., patients with an Injury Severity Score of 9 or greater) who were transported from the scene of injury to a trauma center by ground ambulances of the participating emergency medical services between 2015 and 2017 were included. Exposures of interest were total prehospital time, on-scene time, and transport time. Outcomes were 24-hour and 30-day mortality. Generalized linear models including inverse probability weights for several potential confounders were constructed. A generalized additive model was constructed to enable visual inspection of the association.

RESULTS

We included 22,525 moderately and severely injured patients. Twenty-four-hour and 30-day mortality were 1.3% and 7.3%, respectively. On-scene time per minute was significantly associated with 24-hour (relative risk [RR], 1.029; 95% confidence interval, 1.018-1.040) and 30-day mortality (RR, 1.013; 1.008-1.017). We found that this association was also present in patients with severe injuries, traumatic brain injury, severe abdominal injury, and stab or gunshot wound. An on-scene time of 20 minutes or longer demonstrated a strong association with 24-hour (RR, 1.797; 1.406-2.296) and 30-day mortality (RR, 1.298; 1.180-1.428). Total prehospital (24-hour: RR, 0.998; 0.990-1.007; 30-day: RR, 1.000, 0.997-1.004) and transport (24-hour: RR, 0.996; 0.982-1.010; 30-day: RR, 0.995; 0.989-1.001) time were not associated with mortality.

CONCLUSION

A prolonged on-scene time is associated with mortality in moderately and severely injured patients, which suggests that a reduced on-scene time may be favorable for these patients. In addition, transport time was found not to be associated with mortality.

LEVEL OF EVIDENCE

Prognostic and Epidemiologic; level III.

Relationship Between Prehospital Time and 24-h Mortality in Road Traffic-Injured Patients in Laos

Background

Road traffic injury has long been regarded as a “time-dependent disease.” However, shortening the prehospital time might not improve the outcome in developing countries given the current quality of in-hospital care. We aimed to examine the relationship between the prehospital time and 24-h mortality among road traffic victims in Laos.

Methods

A prospective observational study was conducted using the trauma registry data on traffic-injured patients who were transported by ambulance to a trauma center in the capital city of Laos from May 2018 to April 2019. The analysis focused on patients with non-mild conditions, whose outcomes could be affected by the prehospital time. To examine the relationship between a prehospital time of <60 min and 24-h mortality, a generalized estimating equation model was used incorporating the inverse probability weights utilizing the propensity score for the prehospital time.

Results

Of 701 patients, 73% were men, 91% were riding 2- or 3-wheel motor vehicles during the crash, and 68% had a prehospital time of <60 min. A total of 35 patients died within 24 h after the crash. Compared with those who survived, individuals who died tended to have head and torso injuries. The proportions of 24-h mortality were 4.7% and 5.4% in patients whose prehospital time was <60 min and ≥60 min, respectively. No significant relationship was found between the prehospital time and 24-h mortality.

Conclusion

A shorter prehospital time was not associated with the 24-h survival among road traffic victims in Laos.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00268-022-06445-9.

Locating trauma centers considering patient safety

Trauma continues to be the leading cause of death and disability in the U.S. for those under the age of 44, making it a prominent public health problem. Recent literature suggests that geographical maldistribution of Trauma Centers (TCs), and the resultant increase of the access time to the nearest TC, could impact patient safety and increase disability or mortality. To address this issue, we introduce the Trauma Center Location Problem (TCLP) that determines the optimal number and location of TCs in order to improve patient safety. We model patient safety through a surrogate measure of mistriages, which refers to a mismatch in the injury severity of a trauma patient and the destination hospital. Our proposed bi-objective optimization model directly accounts for the two types of mistriages, system-related under-triage (srUT) and over-triage (srOT), both of which are estimated using a notional tasking algorithm. We propose a heuristic based on the Particle Swarm Optimization framework to efficiently derive a near-optimal solution to the TCLP for realistic problem sizes. Based on 2012 data from the state of Ohio, we observe that the solutions are sensitive to the choice of weights for srUT and srOT, volume requirements at a TC, and the two thresholds used to mimic EMS decisions. Using our approach to optimize that network resulted in over 31.5% reduction in the objective with only 1 additional TC; redistribution of the existing 21 TCs led to 30.4% reduction.

Driving the ambulance: an essential component of emergency medical services: an integrative review

Background

The transport of patients from one location to another is a fundamental part of emergency medical services. However, little interest has been shown in the actual driving of the ambulance. Therefore, this review aimed to investigate how the driving of the ambulance affects the patient and the medical care provided in an emergency medical situation.

Methods

A systematic integrative review using both quantitative and qualitative designs based on 17 scientific papers published between 2011 and 2020 was conducted.

Results

Ambulance driving, both the actual speed, driving pattern, navigation, and communication between the driver and the patient, influenced both the patient’s medical condition and the possibility of providing adequate care during the transport. The driving itself had an impact on prehospital time spent on the road, safety, comfort, and medical issues. The driver’s health and ability to manage stress caused by traffic, time pressure, sirens, and disturbing moments also significantly influenced ambulance transport safety.

Conclusions

The driving of the ambulance had a potential effect on patient health, wellbeing, and safety. Therefore, driving should be considered an essential part of the medical care offered within emergency medical services, requiring specific skills and competence in both medicine, stress management, and risk approaches in addition to the technical skills of driving a vehicle. Further studies on the driving, environmental, and safety aspects of being transported in an ambulance are needed from a patient’s perspective.

The contribution of helicopter emergency medical services in the pre-hospital care of penetrating torso injuries in a semi-rural setting

BACKGROUND

Although the merit of pre-hospital critical care teams such as Helicopter Emergency Medical Services (HEMS) has been universally recognized for patients with penetrating torso injuries who present with unstable physiology, the potential merit in patients initially presenting with stable physiology is largely undetermined. The ability to predict the required pre-hospital interventions patients may have important implications for HEMS tasking, especially when transport times to definitive care are prolonged.

METHODS

We performed a retrospective cohort study of patients who sustained a penetrating torso injury and were attended by the Air Ambulance Kent Surrey Sussex (AAKSS) over a 6-year period. Primary outcome was defined as the percentage of patients with penetrating torso injuries requiring HEMS-specific interventions anytime between HEMS arrival and arrival at hospital. Secondary outcomes were the association of individual patient- and injury characteristics with the requirement for HEMS interventions.

RESULTS

During the study period 363 patients met inclusion criteria. 90% of patients were male with a median age of 30 years. 99% of penetrating trauma incident occurred more than 10-min drive from a Major Trauma Centre (MTC). Presenting GCS was > 13 in 83% of patients. Significant hemodynamic- or ventilatory compromise was present in more than 25% of the patients. Traumatic cardiac arrest was present in 34 patients (9.4%), profound hypotension with SBP < 80 mmHg in 30 (8.3%) and oxygen saturations < 92% in 30 (8.3%). A total of 121 HEMS-specific interventions were performed. Although HEMS-specific interventions were associated with presenting physiology (TCA OR 1.75 [1.41-2.16], SBP < 80 mmHg (OR 1.40 [1.18-1.67] and SpO₂ < 92% (OR 1.39 [1.17-1.65], a minority of the patients presented initially with stable physiology but deteriorated on route to hospital and required HEMS interventions (n = 9, 3.3%).

CONCLUSION

HEMS teams provide potentially important contribution to the pre-hospital treatment of patients with penetrating torso injuries in rural and semi-rural areas, especially when they present with unstable physiology. A certain degree of over-triage is inevitable in these patients, as it is hard to predict which patients will deteriorate on route to hospital and will need HEMS interventions. The results of this study showing a potentially predictable geographical dispersion of penetrating trauma could inform multi-agency knife crime prevention strategy.

Injury and Mortality Profiles in Level II and III Trauma Centers

BACKGROUND

While the benefit of admission to trauma centers compared to non-trauma centers is well-documented and differences in outcomes between Level-I and Level-II trauma centers are well-studied, data on the differences in outcomes between Level-II trauma centers (L2TCs) and Level-III trauma centers (L3TCs) are scarce.

OBJECTIVES

We sought to compare mortality risk between patients admitted to L2TCs and L3TCs, hypothesizing no difference in mortality risk for patients treated at L3TCs compared to L2TCs.

METHODS

A retrospective analysis of the 2016 Trauma Quality Improvement Program (TQIP) database was performed. Patients aged 18+ years were divided into 2 groups, those treated at American College of Surgeons (ACS) verified L2TCs and L3TCs.

RESULTS

From 74,486 patients included in this study, 74,187 (99.6%) were treated at L2TCs and 299 (.4%) at L3TCs. Both groups had similar median injury severity scores (ISSs) (10 vs 10, P < .001); however, L2TCs had a higher mean ISS (14.6 vs 11.9). There was a higher mortality rate for L2TC patients (6.0% vs 1.7%, P = .002) but no difference in associated risk of mortality between the 2 groups (OR .46, CI .14-1.50, P = .199) after adjusting predictors of mortality. L2TC patients had a longer median length of stay (5.0 vs 3.5 days, P < .001). There was no difference in other outcomes including myocardial infarction (MI) and cerebrovascular accident (CVA) (P > .05).

DISCUSSION

Patients treated at L2TCs had a longer LOS compared to L3TCs. However, after controlling for covariates, there was no difference in associated mortality risk between L2TC and L3TC patients.

Optimizing Emergency Medical Service Structures Using a Rule-Based Discrete Event Simulation-A Practitioner's Point of View

Many studies in research deal with optimizing emergency medical services (EMS) on both the operational and the strategic level. It is the purpose of this method-oriented article to explain the major features of “rule-based discrete event simulation” (rule-based DES), which we developed independently in Germany and Switzerland. Our rule-based DES addresses questions concerning the location and relocation of ambulances, dispatching and routing policies, and EMS interplay with other players in prehospital care. We highlight three typical use cases from a practitioner’s perspective and go into different countries’ peculiarities. We show how research results are applied to EMS and healthcare organizations to simulate and optimize specific regions in Germany and Switzerland with their strong federal structures. The rule-based DES serves as basis for decision support to improve regional emergency services’ efficiency without increasing cost. Finally, all simulation-based methods suggest normative solutions and optimize EMS’ performance within given healthcare system structures. We argue that interactions between EMS, emergency departments, and public healthcare agencies are crucial to further improving effectiveness, efficiency, and quality.

A Tale of Two Cities: What’s Driving the Firearm Mortality Difference in Two Large Urban Centers?

Introduction

Per police data, the case fatality rate (CFR) of firearm assault in New Orleans (NO) over the last several years ranged between 27% and 35%, compared with 18%-22% in Philadelphia. The reasons for this disparity are unknown, and potentially reflect important system differences with broader implications for the reduction of firearm mortality.

Methods

A retrospective analysis of police and city-specific trauma databases between 2012 and 2017 was performed. Victims of firearm assaults within city limits were included. Univariate analysis was performed using chi-square for categorical and t-test for continuous variables. Bivariate analysis was conducted using logistic regression.

Results

Per police data, the CFR of firearm assault was 31% in NO and 20% in Philadelphia. However, per trauma registry data, the CFR of firearm assault was 14% in NO and 25% in Philadelphia. Patients in Philadelphia were older, had higher injury severity score, and lower blood pressure. Patients in NO had higher rates of head injury. 51% of patients in Philadelphia arrived via police compared to <1% in NO. There was no mortality difference between police and emergency medical service (EMS) transport. Longer EMS prehospital times were associated with increased mortality in NO but not Philadelphia. A much larger percentage of patients died on-scene in NO than Philadelphia.

Conclusions

Our findings suggest that the major driver of increased mortality following firearm assault in NO compared with Philadelphia is death prior to the arrival of first responders. Interventions that shorten prehospital time will likely have the greatest impact on mortality in NO. This should include the consideration of police transport.

A scoping review of worldwide studies evaluating the effects of prehospital time on trauma outcomes

BACKGROUND

Annually, over 1 billion people sustain traumatic injuries, resulting in over 900,000 deaths in Africa and 6 million deaths globally. Timely response, intervention, and transportation in the prehospital setting reduce morbidity and mortality of trauma victims. Our objective was to describe the existing literature evaluating trauma morbidity and mortality outcomes as a function of prehospital care time to identify gaps in literature and inform future investigation.

MAIN BODY

We performed a scoping review of published literature in MEDLINE. Results were limited to English language publications from 2009 to 2020. Included articles reported trauma outcomes and prehospital time. We excluded case reports, reviews, systematic reviews, meta-analyses, comments, editorials, letters, and conference proceedings. In total, 808 articles were identified for title and abstract review. Of those, 96 articles met all inclusion criteria and were fully reviewed. Higher quality studies used data derived from trauma registries. There was a paucity of literature from studies in low- and middle-income countries (LMIC), with only 3 (3%) of articles explicitly including African populations. Mortality was an outcome measure in 93% of articles, predominantly defined as "in-hospital mortality" as opposed to mortality within a specified time frame. Prehospital time was most commonly assessed as crude time from EMS dispatch to arrival at a tertiary trauma center. Few studies evaluated physiologic morbidity outcomes such as multi-organ failure.

CONCLUSION

The existing literature disproportionately represents high-income settings and most commonly assessed in-hospital mortality as a function of crude prehospital time. Future studies should focus on how specific prehospital intervals impact morbidity outcomes (e.g., organ failure) and mortality at earlier time points (e.g., 3 or 7 days) to better reflect the effect of early prehospital resuscitation and transport. Trauma registries may be a tool to facilitate such research and may promote higher quality investigations in Africa and LMICs.

Zero Preventable Deaths by 2020: Analysis of Prehospital and Emergency Department Deaths Following Penetrating Trauma Stratified by Anatomic Location

INTRODUCTION

Preventable deaths following trauma are high and unchanged over the last two decades. The objective of this study was to describe the location of death in patients with penetrating trauma, stratified by anatomic location of injury, in order to better tailor our approach to reducing preventable deaths from trauma.

METHODS

This retrospective analysis of a prospectively maintained trauma registry included consecutive adult trauma activations with penetrating trauma at a level 1 trauma center between 07/2012 and 03/2018. Injuries were categorized as extremity, junctional, and torso. Head and neck injuries were excluded. Patients injured in >1 defined location were categorized as "multiple." Location of death was defined as on-scene, emergency department (ED), or hospital. Two-sided χ² tests were used to compare groups. Multivariate analysis was performed using logistic regression.

RESULTS

A total of 1024 patients were included with an overall case fatality rate (CFR) of 7.8%. The CFR following extremity injury (3.0%) was significantly lower than all other injury sites (P = .02).There were no significant differences in CFR for junctional (10.4%), torso (8.3%), or multiple injuries (9.6%). Forty percent of fatalities following junctional injury occurred on-scene and an additional 20% occurred in the ED.

DISCUSSION

To our knowledge, this is the first study to describe location of death stratified by anatomic location of injury. There was no difference in the CFRs of junctional and torso injuries, and a large proportion of deaths occurred prior to reaching the hospital or in the trauma bay. These findings support reevaluating the classical algorithms and care pathways for patients with proximal penetrating trauma.

Using publicly available flight data to analyze health disparities in aeromedical retrieval

OBJECTIVES

Specialist healthcare cannot be provided in all locations. Helicopters can help to reduce the inherent geographical inequity caused by long distances or difficult terrain. However, the selective use of aeromedical retrieval could lead to other forms of health disparities. The aim of this project was to evaluate such inequities in access to helicopter transport.

METHODS

This was a geospatial analysis of publicly available flight tracking data for 18 emergency medical helicopters in the state of Alabama for a 90-day period between March 2019 and June 2019. Data are presented as the number of incidents attended per population, by population (total, insured, and uninsured), as funnel plots, by county. This method allows the identification of positive and negative outliers.

RESULTS

We identified 672 likely scene retrieval flights. Twelve counties were probable (outside of 99% confidence interval [CI]) high outliers (more helicopter retrievals than expected), and 4 were possible (outside of 95% CI) high outliers. There were 5 possible low outliers (fewer helicopter retrievals than expected) and 6 probable low outliers. Analysis by insurance status revealed similar results. However, there was no easily discernible geographic pattern to this variability.

CONCLUSION

There is considerable geographical variability in the number of helicopter retrievals, with no easily discernable pattern. Some of this variability may be due to differences in injury epidemiology, but others may be due to case selection. However, the present data are insufficient to come to firm conclusions, and additional study is warranted.

Mortality of trauma patients treated at trauma centers compared to non-trauma centers in Sweden: a retrospective study

Objective

The main objective was to compare the 30-day mortality rate of trauma patients treated at trauma centers as compared to non-trauma centers in Sweden. The secondary objective was to evaluate how injury severity influences the potential survival benefit of specialized care.

Methods

This retrospective study included 29,864 patients from the national Swedish Trauma Registry (SweTrau) during the period 2013–2017. Three sampling exclusion criteria were applied: (1) Injury Severity Score (ISS) of zero; (2) missing data in any variable of interest; (3) data falling outside realistic values and duplicate registrations. University hospitals were classified as trauma centers; other hospitals as non-trauma centers. Logistic regression was used to analyze the effect of trauma center care on mortality rate, while adjusting for other factors potentially affecting the risk of death.

Results

Treatment at a trauma center in Sweden was associated with a 41% lower adjusted 30-day mortality (odds ratio 0.59 [0.50–0.70], p < 0.0001) compared to non-trauma center care, considering all injured patients (ISS ≥ 1). The potential survival benefit increased substantially with higher injury severity, with up to > 70% mortality decrease for the most critically injured group (ISS ≥ 50).

Conclusions

There exists a potentially substantial survival benefit for trauma patients treated at trauma centers in Sweden, especially for the most severely injured. This study motivates a critical review and possible reorganization of the national trauma system, and further research to identify the characteristics of patients in most need of specialized care.

Helicopter Transport Has Decreased Over Time and Transport From Scene or Hospital Matters

OBJECTIVE

Several reports have found helicopter emergency medical services (HEMS) to be associated with a lower risk of mortality compared with ground emergency medical services (GEMS); however, most studies did not control for transport time or stratify interfacility versus scene. We hypothesize that the HEMS transport rate has decreased nationally and that the risk of mortality for HEMS is similar to GEMS when adjusting for transport time and stratifying by scene or interfacility.

METHODS

The Trauma Quality Improvement Program (2010-2016) was queried for adult patients transported by HEMS or GEMS. Multivariable logistic regression was used.

RESULTS

The HEMS transport rate decreased by 38.2% from 2010 to 2016 (P < .001). After controlling for known predictors of mortality and transport time, HEMS was associated with a decreased risk of mortality compared with GEMS for adult trauma patient transports (odds ratio = 0.74; 95% confidence interval [CI], 0.71-0.77; P < .001). Compared with GEMS, HEMS transports from the scene were associated with a decreased risk of mortality (OR = 0.63; 95% CI, 0.60-0.66; P < .001), whereas HEMS interfacility transfer was associated with an increased risk of mortality (OR = 1.22; 95% CI, 1.14-1.31; P < .001).

CONCLUSION

The rate of HEMS transports in trauma has decreased by nearly 40% over the past 7 years. Our results suggest that HEMS use for scene transports is beneficial for the survival of trauma patients.