Physician-based emergency medical service deployment characteristics in severe traumatic brain injury: a Dutch multicenter study

Treatment of pediatric patients with traumatic brain injury by Dutch Helicopter Emergency Medical Services (HEMS)

BACKGROUND

Sparse data are available on prehospital care by Helicopter Emergency Medical Service (HEMS) for pediatric patients with traumatic brain injury (TBI). This study focusses on prehospital interventions, neurosurgical interventions and mortality in this group.

METHODS

We performed a retrospective analysis of pediatric (0-18 years of age) patients with TBI treated by Rotterdam HEMS.

RESULTS

From January 2012 to December 2017 415 pediatric (<18 years of age) patients with TBI were included. Intubation was required in in 92 of 111 patients with GCS ≤ 8, 92 (82.9%), compared to 12 of 77 (15.6%) with GCS 9-12, and 7 of 199 (3.5%) with GCS 13-15. Hyperosmolar therapy (HSS) was started in 73 patients, 10 with a GCS ≤8. Decompressive surgery was required in 16 (5.8%), nine patients (56.3%) of these received HSS from HEMS. Follow-up data was available in 277 patients. A total of 107 (38.6%) patients were admitted to a (P)ICU. Overall mortality rate was 6.3%(n = 25) all with GCS ≤8, 15 (60.0%) died within 24 hours and 24 (96.0%) within a week. Patients with neurosurgical interventions (N = 16) showed a higher mortality rate (18.0%).

CONCLUSIONS

The Dutch HEMS provides essential emergency care for pediatric TBI patients, by performing medical procedures outside of regular EMS protocol. Mortality was highest in patients with severe TBI (n = 111) (GCS≤8) and in those who required neurosurgical interventions. Despite a relatively good initial GCS (>8) score, there were patients who required prehospital intubation and HSS. This group will require further investigation to optimize care in the future.

Improving ambulance dispatch triage to trauma: A scoping review using the framework of development and evaluation of clinical prediction rules

OBJECTIVE

Ambulance dispatch algorithms should function as clinical prediction rules, identifying high acuity patients for advanced life support, and low acuity patients for non-urgent transport. Systematic reviews of dispatch algorithms are rare and focus on study types specific to the final phases of rule development, such as impact studies, and may miss the complete value-added evidence chain. We sought to summarise the literature for studies seeking to improve dispatch in trauma by performing a scoping review according to standard frameworks for developing and evaluating clinical prediction rules.

METHODS

We performed a scoping review searching MEDLINE, EMBASE, CINAHL, the CENTRAL trials registry, and grey literature from January 2005 to October 2021. We included all study types investigating dispatch triage to injured patients in the English language. We reported the clinical prediction rule phase (derivation, validation, impact analysis, or user acceptance) and the performance and outcomes measured for high and low acuity trauma patients.

RESULTS

Of 2067 papers screened, we identified 12 low and 30 high acuity studies. Derivation studies were most common (52%) and rule-based computer-aided dispatch was the most frequently investigated (23 studies). Impact studies rarely reported a prior validation phase, and few validation studies had their impact investigated. Common outcome measures in each phase were infrequent (0 to 27%), making a comparison between protocols difficult. A series of papers for low acuity patients and another for pediatric trauma followed clinical prediction rule development. Some low acuity Medical Priority Dispatch System codes are associated with the infrequent requirement for advanced life support and clinician review of computer-aided dispatch may enhance dispatch triage accuracy in studies of helicopter emergency medical services.

CONCLUSIONS

Few derivation and validation studies were followed by an impact study, indicating important gaps in the value-added evidence chain. While impact studies suggest clinician oversight may enhance dispatch, the opportunity exists to standardize outcomes, identify trauma-specific low acuity codes, and develop intelligent dispatch systems.

Risk factors for cancellation after dispatch of rapid response cars for prehospital emergency care: a single-center, case-control study

Aim

The objective of this study is to identify the risk factors for cancellation after dispatch of rapid response cars (RRC) for prehospital emergency care.

Methods

We retrospectively extracted data from all RRC cases dispatched from our hospital between April 2017 and March 2019. A total of 1,440 cases were included in our study and divided into either the “cancelled” group (n = 723) or the “treated” group (n = 717), based on the occurrence of cancellation. The variables obtained from the request calls for RRC included patient characteristics, distance from the hospital to the scene, and reasons for RRC request. The variables were compared between the two groups and logistic regression analysis was carried out to identify the risk factors for RRC cancellation.

Results

Multivariable analysis showed that distance from the hospital to the scene (odds ratio [OR] 1.25; 95% confidence interval (CI), 1.21–1.28), suspicion of cardiopulmonary arrest with no witness information (OR 7.61; 95% CI, 4.13–14.00), dyspnea (OR 2.22; 95% CI, 1.19–4.11), and suicide by hanging (OR 3.49; 95% CI, 1.37–8.89) were independent risk factors for cancellation.

Conclusions

In our study, a greater distance from the hospital to the scene, suspicion of cardiopulmonary arrest with no witness information, dyspnea, and suicide by hanging were identified as independent risk factors for cancellation after dispatch of RRC. Evaluating the risk factors for cancellation at individual facilities could help hospitals adjust their dispatch criteria to allocate limited medical resources more effectively.

Face-to-Face Versus Telephonic Extended Glasgow Outcome Score Testing After Traumatic Brain Injury

OBJECTIVE

The Extended Glasgow Outcome Scale (GOS-E) is used for objective assessment of functional outcome in traumatic brain injury (TBI). In situations where face-to-face contact is not feasible, telephonic assessment of the GOS-E might be desirable. The aim of this study is to assess the level of agreement between face-to-face and telephonic assessment of the GOS-E.

SETTING

Multicenter study in 2 Dutch University Medical Centers. Inclusion was performed in the outpatient clinic (face-to-face assessment, by experienced neurologist), followed by assessment via telephone of the GOS-E after ±2 weeks (by trained researcher).

PARTICIPANTS

Patients ±6 months after TBI.

DESIGN

Prospective validation study.

MAIN MEASURES

Interrater agreement of the GOS-E was assessed with Cohen's weighted κ.

RESULTS

From May 2014 until March 2018, 50 patients were enrolled; 54% were male (mean age 49.1 years). Median time between trauma and in-person GOS-E examination was 158 days and median time between face-to-face and telephonic GOS-E was 15 days. The quadratic weighted κ was 0.79. Sensitivity analysis revealed a quadratic weighted κ of 0.77, 0.78, and 0.70 for moderate-severe, complicated mild, and uncomplicated mild TBI, respectively.

CONCLUSION

No disagreements of more than 1 point on the GOS-E were observed, with the κ value representing good or substantial agreement. Assessment of the GOS-E via telephone is a valid alternative to the face-to-face interview when in-person contact is not feasible.

Epidemiology, Prehospital Characteristics and Outcomes of Severe Traumatic Brain Injury in The Netherlands: The BRAIN-PROTECT Study

OBJECTIVE

A thorough understanding of the epidemiology, patient characteristics, trauma mechanisms, and current outcomes among patients with severe traumatic brain injury (TBI) is important as it may inform potential strategies to improve prehospital emergency care. The aim of this study is to describe the prehospital epidemiology, characteristics and outcome of (suspected) severe TBI in the Netherlands.

METHODS

The BRAIN-PROTECT study is a prospective observational study on prehospital management of patients with severe TBI in the Netherlands. The study population comprised all consecutive patients with clinical suspicion of TBI and a prehospital GCS score ≤ 8, who were managed by one of the 4 Helicopter Emergency Medical Services (HEMS). Patients were followed-up in 9 trauma centers until 1 year after injury. Planned sub-analyses were performed for patients with "confirmed" and "isolated" TBI.

RESULTS

Data from 2,589 patients, of whom 2,117 (81.8%) were transferred to a participating trauma center, were analyzed. The incidence rate of prehospitally suspected and confirmed severe TBI were 3.2 (95% CI: 3.1;3.4) and 2.7 (95% CI: 2.5;2.8) per 100,000 inhabitants per year, respectively. Median patient age was 46 years, 58.4% were involved in traffic crashes, of which 37.4% were bicycle related. 47.6% presented with an initial GCS of 3. The median time from HEMS dispatch to hospital arrival was 54 minutes. The overall 30-day mortality was 39.0% (95% CI: 36.8;41.2).

CONCLUSION

This article summarizes the prehospital epidemiology, characteristics and outcome of severe TBI in the Netherlands, and highlights areas in which primary prevention and prehospital care can be improved.

Do pre-hospital physicians improve mortality in major trauma patients? A systematic review

Background

Optimal pre-hospital care systems contribute to improvements in trauma survival. The presence of pre-hospital physicians (PHPs) is reported to increase survival in traumatic brain injury, yet the effects of PHPs on outcomes for all trauma patients is currently unreported. The objective of this systematic review was to compare trauma mortality for patients treated by a PHP with those treated by a non-medical pre-hospital practitioner (NMPHP).

Methods

A systematic literature search (Medline, Embase, and CINAHL) was performed, on 10th March 2020, to identify original studies comparing the mortality for trauma patients treated by a PHP with those treated by a NMPHP published between 1st January 2010 and 31st December 2019. Methodological quality of studies was assessed using Grade of Recommendations, Assessment, Development and Evaluation (GRADE).

Results

The search revealed 6,296 studies and 14 met the inclusion criteria, comprising a total of 42,479 patients. Unadjusted mortality suggested a higher mortality for the physician cohort in four studies and no difference in six. However, patients treated by physicians had higher Injury Severity Scores and where adjusted mortality was provided several studies showed a mortality benefit for physicians.

Conclusion

This systematic review did not demonstrate a mortality benefit from pre-hospital physicians attending major trauma patients. However, those with higher Injury Severity Scores may benefit from the presence of a PHP. Identifying this patient cohort in the pre-hospital setting to ensure appropriate resource use requires further evaluation.

Advanced Prehospital Trauma Resuscitation With a Physician and Certified Registered Nurse Anesthetist: The Shock Trauma "Go-Team"

OBJECTIVE

The R Adams Cowley Shock Trauma Center (STC) is Maryland's primary adult resource center for trauma care. The Shock Trauma "Go-Team" is a specialized component of Maryland's emergency medical system and is composed of a physician and certified registered nurse anesthetist. They are dispatched when advanced prehospital resuscitation is required. The purpose of this study is to describe the capabilities and historic epidemiology outcomes of the Go-Team.

METHODS

A retrospective case series review of recoverable Go-Team records was performed from 2011 to 2018. Go-Team call logs/records were identified from multiple sources. Medical records were reviewed for patient demographics, mechanisms of injury, and treatments in the field. There was a total of 61 activations, with 22 deployments to the scene of injury.

RESULTS

The majority of deployments were via helicopter (73%) and lasted 2 hours. The most common indications for deployment were motor vehicle entrapment (41%), trench collapse (14%), and building collapse (9%). Of the 22 patients treated by the Go-Team, 50% received at least 1 blood transfusion in the field, and 23% required an advanced airway. No field amputations were required.

CONCLUSION

The STC Go-Team is a unique multidisciplinary specialized component of a statewide emergency medical system.

Effect of Physician-Staffed Emergency Medical Services (P-EMS) on the Outcome of Patients with Severe Traumatic Brain Injury: A Review of the Literature

Introduction: Traumatic injury is the fourth leading cause of death in western countries and the leading cause of death in younger age. However, it is still unclear which groups of patients benefit most from advanced prehospital trauma care. A minimal amount is known about the effect of prehospital physician-based care on patients with specifically traumatic brain injury (TBI). The aim of this review is to assess the effect of physician-staffed Emergency Medical Services (EMS) on the outcome of patients with severe TBI. Methods: Literature searches have been performed in the bibliographic databases of PubMed, EMBASE and The Cochrane Library. Data concerning (physician-staffed) prehospital care for patients with severe TBI were only included if the control group was based on non-physician-staffed EMS. Primarily the mortality rate and secondarily the neurological outcome were examined. Additionally, data concerning hypotension, hypoxia, length of stay (hospital and intensive care unit) and the number of required early neurosurgical interventions were taken into account. Results: The overall mortality was decreased in three of the fourteen included studies after the implementation of a physician in the prehospital setting. One study found also a decrease in mortality only for patients with a Glasgow Coma Scale of 6-8. Strikingly, two other studies reported higher mortality, one for all the included patients and one for patients with GCS 10-12 only. Neurological outcome was improved in five studies after prehospital deployment of a physician. One study reported that more patients had a poor neurological outcome in the P-EMS group. Results of the remaining outcome measures differed widely. Conclusion: The included literature did not show a clear beneficial effect of P-EMS in the prehospital management of patients with severe TBI. The available evidence showed contradictory results, suggesting more research should be performed in this field with focus on decreasing heterogeneity in the compared groups.

Prehospital and Emergency Care in Adult Patients with Acute Traumatic Brain Injury

Traumatic brain injury (TBI) is a major healthcare problem and a major burden to society. The identification of a TBI can be challenging in the prehospital setting, particularly in elderly patients with unobserved falls. Errors in triage on scene cannot be ruled out based on limited clinical diagnostics. Potential new mobile diagnostics may decrease these errors. Prehospital care includes decision-making in clinical pathways, means of transport, and the degree of prehospital treatment. Emergency care at hospital admission includes the definitive diagnosis of TBI with, or without extracranial lesions, and triage to the appropriate receiving structure for definitive care. Early risk factors for an unfavorable outcome includes the severity of TBI, pupil reaction and age. These three variables are core variables, included in most predictive models for TBI, to predict short-term mortality. Additional early risk factors of mortality after severe TBI are hypotension and hypothermia. The extent and duration of these two risk factors may be decreased with optimal prehospital and emergency care. Potential new avenues of treatment are the early use of drugs with the capacity to decrease bleeding, and brain edema after TBI. There are still many uncertainties in prehospital and emergency care for TBI patients related to the complexity of TBI patterns.

Does prehospital management by doctors affect outcome in major trauma? A systematic review

BACKGROUND

There is substantial variation worldwide in prehospital management of trauma and the role of doctors is controversial. The objective of this review was to determine whether prehospital management by doctors affects outcomes in major trauma, including the prespecified subgroup of severe traumatic brain injuries when compared with management by other advanced life support providers.

METHODS

EMBASE, MEDLINE(R), PubMed, SciELO, Trip, Web of Science, and Zetoc were searched for published articles. HSRProj, OpenGrey, and the World Health Organization International Clinical Trials Registry Platform were searched for unpublished data. Relevant reference lists were hand-searched. There were no limits on publication year, but articles were limited to the English language. Authors were contacted for further information as required. Quality was assessed using the Downs and Black criteria. Mortality was the primary outcome, and disability was the secondary outcome of interest. Studies were subjected to a descriptive analysis alone without a meta-analysis due to significant study heterogeneity. All searches, quality assessment, data abstraction, and data analysis was performed by two reviewers independently.

RESULTS

Two thousand thirty-seven articles were identified, 49 full-text articles assessed and eight studies included. The included studies consisted of one randomized controlled trial with 375 participants and seven observational studies with over 4,451 participants. All included studies were at a moderate to high risk of bias. Six of the eight included studies showed an improved outcome with prehospital management by doctors, five in terms of mortality and one in terms of disability. Two studies found no significant difference.

CONCLUSION

There appears to be an association between prehospital management by doctors and improved survival in major trauma. There may also be an association with improved survival and better functional outcomes in severe traumatic brain injury. Further high-quality evidence is needed to confirm these findings.

LEVEL OF EVIDENCE

Systematic review, level III.

Impact of rapid response car system on ECMO in out-of-hospital cardiac arrest: A retrospective cohort study

INTRODUCTION

Extracorporeal life support (ECLS) has been reported to be more effective than conventional cardiopulmonary resuscitation (CPR). In ECLS, a shorter time from arrival to implantation of extracorporeal membrane oxygenation (ECMO; door-to-ECMO) time was predicted to be associated with better survival rates. This study aimed to examine the impact of the physician-based emergency medical services (P-EMS) using a rapid response car (RRC) on door-to-ECMO time in patients with out-of-hospital cardiac arrest (OHCA).

METHODS

In this retrospective cohort study, adult patients with OHCA who were admitted to a Japanese tertiary care hospital from April 2012 to December 2016 and underwent venoarterial ECMO were included. Patients were either transferred by emergency medical service (EMS only group) or RRC (RRC group). Primary outcome was door-to-ECMO time. Wilcoxon rank-sum test was used to compare the outcome between the two groups.

RESULTS

A total of 34 patients were included in this study, and outcome data were available for all patients. The door-to-ECMO time was significantly shorter in the RRC group than in the EMS only group (median, 23min vs. 36min; P=0.006). Additionally, the RRC was also associated with earlier successful intubation and intravenous adrenaline administration.

CONCLUSION

The physician-based RRC system was associated with a shorter door-to-ECMO time and successful advanced procedures in prehospital settings. Combination of the RRC system with ECLS may lead to better outcomes in patients with OHCA.

HEMS dispatch: A systematic review

Introduction

Helicopter emergency medical services dispatch is a contentious issue in modern prehospital services. Whilst the link between helicopter emergency medical services and improved patient outcome is well evidenced, allocation to the most appropriate incidents remains problematic. It is unclear which model of deployment is the most efficient at targeting major trauma and whether this can be improved with a change in dispatch process. The objective of this study was to have an overview of the evidence for dispatch models of helicopter emergency medical services to critically ill or injured patients.

Methods

This systematic review was conducted in accordance with a protocol developed from the PRISMA guidelines. MEDLINE, Embase, CINAHL and the Cochrane library were searched focusing on keywords involving dispatch of helicopter emergency medical services resources.

Results

Ninety-seven articles were screened and 14 articles were eligible for inclusion. Most were of low quality, with three of moderate quality. Heterogeneity in the methodology of included articles precluded meta-analysis, so a narrative review was performed.

Conclusions

This review demonstrates the lack of evidence surrounding helicopter emergency medical services dispatch models. Whilst it is not possible to identify a method of dispatch that will optimize helicopter emergency medical services allocation, common themes within the literature indicate that helicopter emergency medical services use is region specific and dispatch criteria should be designed to match specific systems. Additionally, mechanism of injury as well as physiological data from scene was shown to be the most accurate indicator for helicopter emergency medical services attendance.

The Effect of Prehospital Intubation on Treatment Times in Patients With Suspected Traumatic Brain Injury

OBJECTIVE

This study examines whether, in patients requiring intubation with moderate to severe traumatic brain injury (TBI), prehospital intubation compared with emergency department intubation leads to a reduction in treatment times and time to a computed tomographic (CT) scan.

METHODS

A retrospective cohort study compared adult patients with a Glasgow Coma Score of less than 14 with a suspected TBI who underwent intubation, either prehospital or on arrival to the emergency department.

RESULTS

Prehospital intubation was associated with a decreased time from emergency department arrival to CT scan compared with emergency department intubation (43 vs. 54 minutes, P < .001). The prehospital intubation group had a longer median scene time (42 vs. 17 minutes, P ≤ .001), longer median transport times (32 vs. 14 minutes, P ≤ .001), and longer total treatment times (90 vs. 73 minutes, P = .007).

CONCLUSIONS

Patients intubated in the prehospital setting spend a longer time at the scene but a shorter amount of time in the emergency department before brain imaging. Prehospital intubation may lead to earlier control of airway and ventilation. The minority of intubated TBI patients required urgent neurosurgical intervention. Overall prehospital intubation shows no significant survival advantage for the patients when compared with emergency department intubation.

Traumatic brain injury: physiological targets for clinical practice in the prehospital setting and on the Neuro-ICU

PURPOSE OF REVIEW

Over many years, understanding of the pathophysiology in traumatic brain injury (TBI) has resulted in the development of core physiological targets and therapies to preserve cerebral oxygenation, and in doing so prevent secondary insult. The present review revisits the evidence for these targets and therapies.

RECENT FINDINGS

Achieving oxygen, carbon dioxide, blood pressure, temperature and glucose targets remain a key goal of therapy in TBI, as does the role of effective prehospital care. Physician led air ambulance teams reduce mortality. Normobaric hyperoxia is dangerous to the injured brain; as are both high and low carbon dioxide levels. Hypotension is life threatening and higher targets have now been suggested in TBI. Both therapeutic normothermia and hypothermia have a role in specific groups of patients with TBI. Although consensus has not been reached on the optimal intravenous fluid for resuscitation in TBI, vigilant goal-directed fluid administration may improve outcome. Osmotherapeutic agents such as hypertonic sodium lactate solutions may also have a role alongside conventional agents.

SUMMARY

Maintaining physiological targets in several areas remains part of protocol led care in the acute phase of TBI management. As evidence accumulates however, the target values and therefore therapies may be set to change.

The inaugural European emergency medical dispatch conference--a synopsis of proceedings

The inaugural European Emergency Medical Dispatch conference was held in Stockholm, Sweden, in May 2013. We provide a synopsis of the conference proceedings, highlight key topic areas of emergency medical dispatch and suggest future research priorities.