Guidelines for air medical dispatch

Maternal Transport, What Do We Know: A Narrative Review

Objective

This review examines the initial development of a transport system for neonates, followed by a subsequent evolution of a transportation system for the maternal/fetal unit, and then a maternal transport system (antepartum, intrapartum, and postpartum) to specifically address maternal morbidity/mortality.

Methods

A literature search was undertaken using the electronic databases PubMed, Embase, and CINAHL. The search terms used were "maternal transport" AND "perinatal care" OR "labor" "obstetrics" OR "delivery". The years searched were 1960-2023.

Results

There were 260 abstracts identified and 52 of those are the basis of this review. The utilization of a transportation system with the regionalization of levels of care has resulted in a significant reduction in neonatal, perinatal, and maternal morbidity and mortality. Although preterm delivery remains a concern in women transported, the number of deliveries that have occurred during transport is relatively small. Reimbursement for transportation continues to be a problem in several states.

Conclusion

A state-of-the-art transportation system has evolved that transfers neonates, maternal/fetal dyad, and pregnant women (antepartum, intrapartum, postpartum) to the appropriate level of care facility to ensure the best maternal/fetal/neonatal outcomes.

Geospatial assessment of helicopter emergency medical service overtriage

BACKGROUND

Despite evidence of benefit after injury, helicopter emergency medical services (HEMS) overtriage remains high. Scene and transfer overtriage are distinct processes. Our objectives were to identify geographic variation in overtriage and patient-level predictors, and determine if overtriage impacts population-level outcomes.

METHODS

Patients 16 years or older undergoing scene or interfacility HEMS in the Pennsylvania Trauma Outcomes Study were included. Overtriage was defined as discharge within 24 hours of arrival. Patients were mapped to zip code, and rates of overtriage were calculated. Hot spot analysis identified regions of high and low overtriage. Mixed-effects logistic regression determined patient predictors of overtriage. High and low overtriage regions were compared for population-level injury fatality rates. Analyses were performed for scene and transfer patients separately.

RESULTS

A total of 85,572 patients were included (37.4% transfers). Overtriage was 5.5% among scene and 11.8% among transfer HEMS (p < 0.01). Hot spot analysis demonstrated geographic variation in high and low overtriage for scene and transfer patients. For scene patients, overtriage was associated with distance (odds ratio [OR], 1.03; 95% confidence interval [CI], 1.01-1.06 per 10 miles; p = 0.04), neck injury (OR, 1.27; 95% CI, 1.01-1.60; p = 0.04), and single-system injury (OR, 1.37; 95% CI, 1.15-1.64; p < 0.01). For transfer patients, overtriage was associated with rurality (OR, 1.64; 95% CI, 1.22-2.21; p < 0.01), facial injury (OR, 1.22; 95% CI, 1.03-1.44; p = 0.02), and single-system injury (OR, 1.35; 95% CI, 1.18-2.19; p < 0.01). For scene patients, high overtriage was associated with higher injury fatality rate (coefficient, 1.72; 95% CI, 1.68-1.76; p < 0.01); low overtriage was associated with lower injury fatality rate (coefficient, -0.73; 95% CI, -0.78 to -0.68; p < 0.01). For transfer patients, high overtriage was not associated with injury fatality rate (p = 0.53); low overtriage was associated with lower injury fatality rate (coefficient, -2.87; 95% CI, -4.59 to -1.16; p < 0.01).

CONCLUSION

Geographic overtriage rates vary significantly for scene and transfer HEMS, and are associated with population-level outcomes. These findings can help guide targeted performance improvement initiatives to reduce HEMS overtriage.

LEVEL OF EVIDENCE

Therapeutic, level IV.

Association Between Mode of Transportation and Outcomes in Penetrating Trauma Across Different Prehospital Time Intervals: A Matched Cohort Study

BACKGROUND

National guidelines do not provide recommendations concerning optimal dispatch time for helicopter emergency medical services (HEMS) in the United States.

OBJECTIVES

This study describes the association between mode of transport (ground vs. helicopter) and survival of patients with penetrating injury across different prehospital time intervals and proposes evidence-based time-related dispatch criteria for HEMS.

METHODS

A retrospective matched cohort study was conducted using the 2015 National Trauma Data Bank. Adult patients (age ≥ 16 years) with penetrating injuries were included. Patients transported via HEMS were selected and matched (1 to 1) for 17 variables to patients transported by ground ambulance (GEMS). Bivariate analyses were conducted to compare characteristics and outcomes (survival to hospital discharge) of patients across different prehospital time intervals.

RESULTS

Each group consisted of 949 patients. Overall survival rate was similar in both groups (90.6% for HEMS vs. 87.9% for GEMS, p = 0.054). Patients transported by HEMS had significantly higher survival compared with those transported by GEMS (92.5% for HEMS vs. 87.0% for GEMS, p = 0.002) in the 0-60-min time interval from dispatch to arrival to hospital, and more specifically, in the 31-60-min interval (92.2% vs. 85.2%, p = 0.001). No difference in survival between the two groups was observed in the shortest (0-30 min) or in the extended prehospital time intervals (>60 min).

CONCLUSION

In adult patients with penetrating trauma, HEMS transport was associated with improved survival in a specific total prehospital time interval (31 to 60 min). This finding can help emergency medicine service administrators develop evidence-based HEMS dispatch criteria.

Association Between Mode of Transportation and Outcomes of Adult Trauma Patients With Blunt Injury Across Different Prehospital Time Intervals in the United States: A Matched Cohort Study

BACKGROUND

Helicopter Emergency Medical Services (HEMS) dispatch currently depends on predefined protocols, on first responders' initial assessment, or on medical direction decision in some states. National guidelines do not provide recommendations concerning prehospital time criteria.

OBJECTIVE

Our aim was to investigate the association between the mode of transportation (HEMS vs. ground EMS [GEMS]) and survival of adult patients with blunt trauma across different prehospital time intervals.

METHODS

This retrospective matched cohort study was carried out using the 2015 National Trauma Data Bank (NTDB) dataset. Adult patients with blunt injuries transported via HEMS were selected and matched (1 to 1) for 13 variables to those who were transported by GEMS. Survival rates were calculated for the two groups across different prehospital time intervals.

RESULTS

Patients transported by HEMS (n = 16,269) were compared with those transported by GEMS (n = 16,269). Most patients were aged 16 to 64 years (84.0%), male (69.4%), and white (88.0%). Overall survival rate to hospital discharge was significantly higher in the HEMS group (96.8% vs. 96.2%; p = 0.002). Patients transported by HEMS had higher survival rates in the ≤ 30-min interval (97.7% vs. 93.2%; p = 0.004); GEMS patients had higher survival rates in the 61- to 90-min interval (97.4% vs. 96.5%; p = 0.038). No difference in survival rates between the two groups was observed in intervals > 90 min.

CONCLUSIONS

In adult patients with blunt trauma, HEMS transport was associated with overall improved survival rates mainly in the first 30 min after injury. GEMS transport, however, had a survival advantage in the 61- to 90-min total prehospital time interval.

Disparities in Inter-hospital Helicopter Transportation for Hispanics by Geographic Region: A Threat to Fairness in the Era of Thrombectomy

BACKGROUND AND PURPOSE

Mechanical thrombectomy (MT) is a time-dependent therapy that is only available at a limited number of hospitals. As such, patients that live at a considerable distance of those specialized centers often require rapid interhospital emergent evacuation with Helicopter Emergency Medical Services (HEMS) to be considered for MT. It is not known whether the use of HEMS is equitable across different groups of patients.

METHODS

Acute ischemic stroke patients emergently transferred to another facility were identified in a retrospective review of a large Medicare claims database. Mode of transportation (HEMS, advanced, or basic ground ambulances) was determined by CPT codes. Distance from patient's residence to the closest center with MT capabilities was calculated. Generalized linear mixed logit models were used to determine the odds of HEMS relative to ground services for Hispanic and non-Hispanic black (NHB) patients relative to non-Hispanic white (NHW) patients while controlling for confounders.

RESULTS

A total of 8027 patients that underwent emergent interhospital transportation were analyzed. HEMS utilization was 18.1% for NHB, 20.6% for Hispanics, and 21.6% for NHW (P = .054). In adjusted analyses for confounders, including distance to a MT-capable hospital, Hispanic patients were less likely than NHWs to be transported by HEMS. While that association had marginal significance for the whole United States (OR = .76; 95% CI, .57-1.01; P = .055), it was statistically significant for patients living in the southern region of the United States (OR = .6; 95% CI, .40-.92; P = .019).

DISCUSSION

Our findings suggest there is a disparity in the use of HEMS in Hispanic stroke patients compared to NHW. Such a disparity may delay arrival to a MT-capable hospital, delay treatment times, or lead to ineligibility for MT altogether. Given the known benefit of MT and known existing disparities in stroke treatment and outcomes, it is important to further investigate and address disparities in mode of interhospital transportation.

The mission characteristics of a newly implemented rural helicopter emergency medical service

Background

Physician-staffed helicopter emergency services (HEMS) can provide benefit through the delivery of specialist competence and equipment to the prehospital scene and through expedient transport of critically ill patients to specialist care. This paper describes the integration of such a system in a rural Swedish county.

Methods

This is a retrospective database study recording the outcomes of every emergency call centre dispatch request as well as the clinical and operational data from all completed missions during this service’s first year in operation.

Results

During the study period, HEMS completed 478 missions out of which 405 (84,7%) were primary missions to prehospital settings and 73 (15,3%) were inter-hospital critical care transfers. A majority (55,3%) of primary missions occurred in the regions furthest from our hospitals, in municipalities housing only 15,6% of the county’s population. The NACA (IQR) score on primary and secondary missions was 4 (2) and 5 (1), respectively.

Conclusions

This study describes the successful integration of a physician-based air ambulance service in a Scandinavian rural region. Municipalities distant from our hospitals benefitted as they now have access to early specialist intervention and expedient transport to critical hospital care. Our hospitals and most populated areas benefitted from HEMS secondary mission capability as they gained a dedicated ICU transport service that could provide specialist intensive care during rapid inter-hospital transfer.

Clinical predictors of outcomes in patients undergoing emergency air medical transport from Kinmen to Taiwan

Emergency air medical transport (EAMT) is indispensable for acutely or critically ill patients in remote areas. We determined patient-level and transport-specific factors associated with all-cause mortality after EAMT.We conducted a population-based, retrospective cohort study using a prospective registry consisting of clinical/medical records. Study inclusion criteria consisted of all adults undergoing EAMT from Kinmen hospital to the ED of Taipei Veterans General Hospital (TVGH) between January 1, 2006 and December 31, 2012. The primary outcome assessments were 7-day and 30-day mortality.A total of 370 patients transported to TVGH were enrolled in the study with a mean age of 54.5 ± 21.5 (SD) years and with a male predominance (71.6%). The average in-transit time was 1.4 ± 0.4 hours. The 7-day, 30-day, and in-hospital mortality rates were 10.3%, 14.1%, and 14.9%. Among them 33.5% (124/370) were categorized under neurological etiologies, whereas 24.9% (90/370) cardiovascular, followed by 16.2% (60/370) trauma patients. Independent predictors associated with 7-day all-cause mortality were age (odds ratio [OR] 1.043, 95% confidence interval [CI] 1.016-1.070), Glasgow Coma Scale (GCS) (OR 0.730, 95% CI 0.650-0.821), and hematocrit level (OR 0.930, 95% CI 0.878-0.985). Independent predictors associated with 30-day all-cause mortality were age (OR 1.028, 95% CI 1.007-1.049), GCS (OR 0.686, 95% CI 0.600-0.785), hematocrit (OR 0.940, 95% CI 0.895-0.988), hemodynamic instability (OR 5.088 95% CI 1.769-14.635), and endotracheal intubation (OR 0.131 95% CI 0.030-0.569). The 7-day and 30-day mortality were not significantly related to transport-specific factors, such as length of flight, type of paramedic crew on board, or day and season of transport. Clinical patient-level factors, as opposed to transport-level factors, were associated with 7- and 30-day all-cause mortality in patients undergoing interfacility EAMT from Kinmen to Taiwan.

External validation of the Air Medical Prehospital Triage score for identifying trauma patients likely to benefit from scene helicopter transport

BACKGROUND

The Air Medical Prehospital Triage (AMPT) score was developed to identify injured patients who may benefit from scene helicopter emergency medical services (HEMS) transport. External validation using a different data set is essential to ensure reliable performance. The study objective was to validate the effectiveness of the AMPT score to identify patients with a survival benefit from HEMS using the Pennsylvania Trauma Outcomes Study registry.

METHODS

Patients 16 years or older undergoing scene HEMS or ground EMS (GEMS) transport in the Pennsylvania Trauma Outcomes Study registry 2000-2013 were included. Patients with 2 or higher AMPT score points were triaged to HEMS, while those with less than 2 points were triaged to GEMS. Multilevel Poisson regression determined the association of survival with actual transport mode across AMPT score triage assignments, adjusting for demographics, mechanism, vital signs, interventions, and injury severity. Successful validation was defined as no survival benefit for actual HEMS transport in patients triaged to GEMS by the AMPT score, with a survival benefit for actual HEMS transport in patients triaged to HEMS by the AMPT score. Subgroup analyses were performed in patients treated by advanced life support providers and patients with transport times longer than 10 minutes.

RESULTS

There were 222,827 patients included. For patients triaged to GEMS by the AMPT score, actual transport mode was not associated with survival (adjusted relative risk, 1.004; 95% confidence interval, 0.999-1.009; p = 0.08). For patients triaged to HEMS by the AMPT score, actual HEMS transport was associated with a 6.7% increase in the relative probability of survival (adjusted relative risk, 1.067; 95% confidence interval, 1.040-1.083, p < 0.001). Similar results were seen in all subgroups.

CONCLUSIONS

This study is the first to externally validate the AMPT score, demonstrating the ability of this tool to reliably identify trauma patients most likely to benefit from HEMS transport. The AMPT score should be considered when protocols for HEMS scene transport are developed and reviewed.

LEVEL OF EVIDENCE

Epidemiologic/prognostic study, level III; therapeutic/care management study, level IV.

Development and Validation of the Air Medical Prehospital Triage Score for Helicopter Transport of Trauma Patients

OBJECTIVE

The aim of this study was to develop and internally validate a triage score that can identify trauma patients at the scene who would potentially benefit from helicopter emergency medical services (HEMS).

SUMMARY BACKGROUND DATA

Although survival benefits have been shown at the population level, identification of patients most likely to benefit from HEMS transport is imperative to justify the risks and cost of this intervention.

METHODS

Retrospective cohort study of subjects undergoing scene HEMS or ground emergency medical services (GEMS) in the National Trauma Databank (2007-2012). Data were split into training and validation sets. Subjects were grouped by triage criteria in the training set and regression used to determine which criteria had a survival benefit associated with HEMS. Points were assigned to these criteria to develop the Air Medical Prehospital Triage (AMPT) score. The score was applied in the validation set to determine whether subjects triaged to HEMS had a survival benefit when actually transported by helicopter.

RESULTS

There were 2,086,137 subjects included. Criteria identified for inclusion in the AMPT score included GCS <14, respiratory rate <10 or >29, flail chest, hemo/pneumothorax, paralysis, and multisystem trauma. The optimal cutoff for triage to HEMS was ≥2 points. In subjects triaged to HEMS, actual transport by HEMS was associated with an increased odds of survival (AOR 1.28; 95% confidence interval [CI] 1.21-1.36, P < 0.01). In subjects triaged to GEMS, actual transport mode was not associated with survival (AOR 1.04; 95% CI 0.97-1.11, P = 0.20).

CONCLUSIONS

The AMPT score identifies patients with improved survival following HEMS transport and should be considered in air medical triage protocols.

Inter-hospital and intra-hospital patient transfer: Recent concepts

The intra- and inter-hospital patient transfer is an important aspect of patient care which is often undertaken to improve upon the existing management of the patient. It may involve transfer of patient within the same facility for any diagnostic procedure or transfer to another facility with more advanced care. The main aim in all such transfers is maintaining the continuity of medical care. As the transfer of sick patient may induce various physiological alterations which may adversely affect the prognosis of the patient, it should be initiated systematically and according to the evidence-based guidelines. The key elements of safe transfer involve decision to transfer and communication, pre-transfer stabilisation and preparation, choosing the appropriate mode of transfer, i.e., land transport or air transport, personnel accompanying the patient, equipment and monitoring required during the transfer, and finally, the documentation and handover of the patient at the receiving facility. These key elements should be followed in each transfer to prevent any adverse events which may severely affect the patient prognosis. The existing international guidelines are evidence based from various professional bodies in developed countries. However, in developing countries like India, with limited infrastructure, these guidelines can be modified accordingly. The most important aspect is implementation of these guidelines in Indian scenario with periodical quality assessments to improve the standard of care.

Helicopter transportation in the era of thrombectomy: The next frontier for acute stroke treatment and research

Purpose

Many patients suffer a stroke at a significant distance from a specialized center capable of delivering endovascular therapy. As a result, they require rapid transport by helicopter emergency medical services, sometimes while receiving a recombinant tissue plasminogen activator infusion (drip and ship). Despite its critical role in the new era of reperfusion, helicopter emergency medical services remains a poorly evaluated aspect of stroke care.

Method

Comprehensive narrative review of all published articles of helicopter emergency medical services related to acute stroke care in the inter-hospital and pre-hospital settings, including technical aspects and physical environment implications.

Findings

Helicopter emergency medical services transports are conducted during a critical early time period when specific interventions and ancillary care practices may have a significant influence on outcomes. We have limited knowledge of the potential impact of the unusual physical factors generated by the helicopter on the ischemic brain, which affects our ability to establish rational guidelines for ancillary care and the delivery of specific interventions.

Discussion

Unlike the pre-hospital and hospital settings where stroke interventions are delivered, the inter-hospital helicopter emergency medical services transfer setting remains a "black box" for acute stroke care and research. This gap is particularly relevant for many patients living in rural areas, or in congested urban areas, that depend on helicopter emergency medical services for rapid access to a tertiary stroke center.

Conclusion

Addressing the helicopter emergency medical services stroke gap in clinical trials and acute care delivery would homogenize capabilities through all care settings, thus minimizing potential disparities in research access and outcomes based on geographical location.

A retrospective comparison of helicopter transport versus ground transport in patients with severe sepsis and septic shock

Background

Helicopter emergency medical services (HEMS) extend the reach of a tertiary care center significantly. However, its role in septic patients is unclear. Our study was performed to clarify the role of HEMS in severe sepsis and septic shock.

Methods

This is a single-center retrospective cohort study. This study was performed at Mayo Clinic, Rochester, MN, in years 2007–2009. This study included a total of 181 consecutive adult patients admitted to the medical intensive care unit meeting criteria for severe sepsis or septic shock within 24 h of admission and transported from an acute care facility by a helicopter or ground ambulance. The primary predictive variable was the mode of transport. Multiple demographic, clinical, and treatment variables were collected and analyzed with univariate analysis followed by multivariate analysis.

Results

The patients transported by HEMS had a significantly faster median transport time (1.3 versus 1.7 h, p < 0.01), faster time to meeting criteria for severe sepsis or septic shock (1.2 versus 2.9 h, p < 0.01), a higher SOFA score (9 versus 7, p < 0.01), higher incidence of acute respiratory distress syndrome (38 versus 18 %, p = 0.013), higher need for invasive mechanical ventilation (60 versus 41 % p = 0.014), higher ICU mortality (13.3 versus 4.1 %, p = 0.024), and an increased hospital mortality (17 versus 30 %, p = 0.04) when compared to those transported by ground. Distance traveled was not an independent predictor of hospital mortality on multivariate analysis.

Conclusions

HEMS transport is associated with faster transport time, carries sicker patients, and is associated with higher hospital mortality compared with ground ambulance services for patients with severe sepsis or septic shock.

Prehospital Helicopter Air Ambulances Part 2: Utilization Criteria and Training

OBJECTIVES

The decision to request a helicopter air ambulance (HAA) is critical and complex. Emergency medical service (EMS) professionals must know how to appropriately and safely use HAA resources. We sought to describe important criteria for using HAA and the prevalence of HAA-related training among EMS professionals. Then, we identified characteristics associated with receiving training.

METHODS

We sent an electronic questionnaire to all nationally certified EMS professionals. We performed descriptive analyses and multivariable logistic regression modeling.

RESULTS

We received 15,366 responses. Nearly all respondents reported that time to nearest trauma center and mechanism of injury were important in their last decision to use a HAA. About two thirds received HAA safety training (66.7%), whereas 69.0% received HAA utilization training within the past 24 months. Nearly three fourths (74.2%) received training in at least 1 HAA-related topic. Providers working at advanced life support levels, fire-based services, agencies providing 911 response, or in rural communities had greater odds of having received HAA training, whereas women, members of minority ethic/racial groups, and those with higher weekly call volumes had decreased odds.

CONCLUSION

Although their decision-making criteria appear to include the major factors recommended within current evidence-based guidelines, many nationally certified EMS professionals had not received recent HAA training.

When place and time matter: How to conduct safe inter-hospital transfer of patients

Inter-hospital transfer (IHT) of patients is often needed for diagnostic or therapeutic interventions. However, the transfer process carries its own risks as a poorly and hastily conducted transfer could lead to adverse events. In this article, we have reviewed literature on the key elements of IHT process including pre-transfer patient stabilization. We have also discussed various modes of transfer, physiological effects of transfer, possible adverse events and how to avoid or mitigate these. Even critically ill-patients can be transported safely by experienced and trained personnel using appropriate equipment. The patient must be maximally stabilized prior to transfer though complete optimization may be possible only at the receiving hospital. Ground or air transport may be employed depending on the urgency, feasibility and availability. Meticulous pre-transfer check and adherence to standard protocols during the transfer will help keep the entire process smooth and event free. The transport team should be trained to anticipate and manage any possible adverse events, medical or technical, during the transfer. Coordination between the referring and receiving hospitals would facilitate prompt transfer to the definitive destination avoiding delay at the emergency or casualty. Documentation of the transfer process and transfer of medical record and investigation reports are important for maintaining continuity of medical care and for medico-legal purposes.

Flight vibrations and bleeding in helicoptered patients with pelvic fracture

Depending on their amplitude and frequency, vibrations may facilitate bleeding and worsen the prognosis of patients with pelvic fractures transported by helicopter emergency medical services (HEMS). We measured the range of frequencies and amplitudes of forced vibrations produced by the helicopter used by the HEMS of the Italian Friuli Venezia Giulia region on the pelvis of transported persons. We performed 3 flight tests with 3 different volunteers (mass 70, 80, and 90 kg, respectively) loaded on the helicopter's stretcher and recorded the amplitudes and frequencies of vibrations through a triaxis sensor placed on the HEMS stretcher in the pelvis area. The flight profile planned was identical for each of the 3 iterations. Over the whole flight, the frequencies of vibration were between 26.4 and 53.5 Hz, and the greastest amplitude was 0.035 mm. The vibrations recorded in the helicopter may facilitate bleeding in unstable fractures. In the management of patients with pelvic fractures, HEMS crews should provide prehospital care that includes the use of specific splinting devices in addition to the spinal board, which allows an early immobilization of fractures and the limitation of pelvic motion.

Cost-effectiveness of helicopter versus ground emergency medical services for trauma scene transport in the United States

STUDY OBJECTIVE

We determine the minimum mortality reduction that helicopter emergency medical services (EMS) should provide relative to ground EMS for the scene transport of trauma victims to offset higher costs, inherent transport risks, and inevitable overtriage of patients with minor injury.

METHODS

We developed a decision-analytic model to compare the costs and outcomes of helicopter versus ground EMS transport to a trauma center from a societal perspective during a patient's lifetime. We determined the mortality reduction needed to make helicopter transport cost less than $100,000 and $50,000 per quality-adjusted life-year gained compared with ground EMS. Model inputs were derived from the National Study on the Costs and Outcomes of Trauma, National Trauma Data Bank, Medicare reimbursements, and literature. We assessed robustness with probabilistic sensitivity analyses.

RESULTS

Helicopter EMS must provide a minimum of a 15% relative risk reduction in mortality (1.3 lives saved/100 patients with the mean characteristics of the National Study on the Costs and Outcomes of Trauma cohort) to cost less than $100,000 per quality-adjusted life-year gained and a reduction of at least 30% (3.3 lives saved/100 patients) to cost less than $50,000 per quality-adjusted life-year. Helicopter EMS becomes more cost-effective with significant reductions in patients with minor injury who are triaged to air transport or if long-term disability outcomes are improved.

CONCLUSION

Helicopter EMS needs to provide at least a 15% mortality reduction or a measurable improvement in long-term disability to compare favorably with other interventions considered cost-effective. Given current evidence, it is not clear that helicopter EMS achieves this mortality or disability reduction. Reducing overtriage of patients with minor injury to helicopter EMS would improve its cost-effectiveness.

Does helicopter transport impact outcome following trauma?

Helicopter transport (HT) has evolved from military roots into a critical component of trauma systems throughout the world. Concerns over cost and safety continue to challenge the role of HT in the civilian setting. Despite this, recent evidence has demonstrated a survival advantage for trauma patients undergoing HT. For patients transported from the scene of injury, improved survival has been shown in several multicenter studies as well as evaluation of large national databases. Issues of overtriage, however, remain problematic for scene HT and represent a prime area for future research in helicopter emergency medical systems (EMS). Patients undergoing inter-facility transfer have also been shown to have improved outcomes over ground transport in terms of shorter transfer times and increased survival particularly in more severely injured patients. The benefits seen are likely a result of a combination of rapid transport, advanced medical capabilities, and accessibility to remote terrain. Several subgroups of patients undergoing HT have been the subject of study as well. Patients with severe head injury have consistently been shown to have superior outcomes over ground ambulance, attributable to improvements in airway management early in the course of their injury. Conversely, HT for urban and penetrating injury has not seen similar benefits, likely due to proximity of trauma centers and recent advancements in urban EMS systems. The benefits of including physicians in helicopter crews are less clear and vary by region and system. Helicopter transport for trauma does appear to improve outcomes for trauma patients, and optimizing utilization of this valuable resource will be key as the role of helicopter EMS continues to develop within trauma systems.

Trauma-related dispatch criteria for Helicopter Emergency Medical Services in Europe

INTRODUCTION

Helicopter Emergency Medical Services (HEMS) are used worldwide in order to provide potentially life-saving pre-hospital medical support to trauma patients at the accident scene. It is currently unclear how much overlap exists regarding the number and type of dispatch criteria used by individual HEMS organisations. The aim of the current study was to provide an overview of dispatch criteria for trauma cases used by HEMS organisations within Europe, and search for similarities and differences, between countries and HEMS stations.

MATERIALS AND METHODS

HEMS dispatch criteria related to trauma care were obtained from the literature and divided into four groups of criteria and processed in a questionnaire. HEMS providing organisations were identified and contacted by telephone and via email.

RESULTS

Fifty-five of the 65 organisations (85%) that were contacted completed the questionnaire. The criteria "Fall from height", "Lengthy extrication and significant injury" and "Multiple casualty incidents" were used most frequently. Criteria from the subgroup "Patient Characteristics-Co-morbidities and Age" were used the least. In 44 of the organisations the Central Dispatch Centre (CDC) was primarily responsible for HEMS dispatch.

CONCLUSION

This overview demonstrates the lack of uniformity in the use of dispatch criteria for trauma assistance on a national and international level. Furthermore, the activation of HEMS is not only depending on dispatch criterion protocols, but is also influenced by organisational factors like the education of the dispatcher, the training of the EMS personnel, the familiarity with the dispatch criteria, and the responses of bystanders. Future research should aim to identify a general set of criteria with the highest discriminating potential.

Helicopter evacuation of trauma victims in Los Angeles: does it improve survival?

BACKGROUND

The purpose of this study was to investigate the relationship between the method of transport after injury and survival among trauma patients admitted to a Level 1 trauma facility in Los Angeles, California.

METHODS

The trauma registry of LAC+USC Medical Center was reviewed to identify all injured patients evacuated by emergency medical service (EMS) from the injury scene from 1998 to 2007. The study population was divided into those who were airlifted (HEMS) and those who were transported by ground emergency medical service (GEMS) with transportation time that exceeded 30 minutes (GEMS > 30 minutes).

RESULTS

During the 10-year study period, 1,836 patients were airlifted (helicopters for emergency medical service (HEMS)) and 1,537 patients were ground transported (GEMS > 30 minutes). HEMS patients suffered more frequently a penetrating injury (19% vs. 11%, p < 0.001), presented more often hypotensive to the emergency department (4% vs. 1%, p < 0.001), had more frequently a Glasgow Coma Scale (GCS) < or = 8 (9% vs. 3%, p < 0.001) and required more often an intubation at the injury scene (1.6% vs. 0.4%, p < 0.001). However, the transportation time and the total prehospital time were significantly shorter for airlifted patients. After multivariable analysis, the difference in mortality between the two transport modalities was not significant (adjusted odds ratio (95% confidence interval, 0.72 (0.22, 2.35); p = 0.596).

CONCLUSIONS

In a metropolitan Los Angeles trauma system, EMS helicopter transportation of injured patients does not appear to improve overall adjusted survival after injury. There is however a potential benefit for severely injured subgroups of patients due to the shorter prehospital times.

Air medical transport curriculum provides education for medical students

INTRODUCTION

Increased regionalization of healthcare will most likely result in greater utilization of air medical transport (AMT). Education of providers regarding the utilization and capabilities of AMT will be important. This study was undertaken to determine whether our curriculum in AMT provided a useful and satisfying educational experience for medical students

METHODS

The curriculum included three 6-hour fly-along sessions, 2 hours of lectures, 2 hours of case review, an 80-page syllabus listing articles and position papers, and a 3-page writing assignment. The study was a review of the participants' (1st- and 2nd-year medical students) test scores and postelective evaluation for 1 year. The setting was a two-helicopter AMT program based at an urban, university-affiliated level 1 trauma center. Twelve students (1/month) participated in the month-long elective. The students took a 20-item test before and after the elective and a 15-item postelective evaluation (5-point scale: very dissatisfied, dissatisfied, neutral, satisfied, very satisfied). A paired t-test was used to compare the mean pre-test and mean post-test scores. The evaluation data were analyzed descriptively.

RESULTS

The mean number of correct responses on the post-test (M = 18.67, SD = 1.61) was significantly higher than the mean number of correct responses on the pretest (M = 13.83, SD = 2.17), P < .001. All students were either satisfied (56%) or very satisfied (44%) with the lectures and case review. Eleven (91%) were very satisfied with interaction with the crew, and nine (75%) were very satisfied overall (25% satisfied). Seven (58%) were very likely to use AMT in their career, two (16.7%) likely, two (16.7%) unsure, and one (8.3%) unlikely.

CONCLUSIONS

Our curriculum in AMT provided a useful and satisfying educational opportunity for medical students. Their knowledge of AMT increased, and all were satisfied or very satisfied with the didactics and the crew interaction. Most thought that they would use AMT in their career.

Management of suspected myocarditis during critical-care transport

Myocarditis and malignant dysrhythmias are unusual presentations in pediatric patients. We report a series of 4 patients with myocarditis and arrhythmia who presented to community emergency departments and were transported to a pediatric tertiary-care center. Three of the patients required extracorporeal life support. We discuss considerations for stabilization and transport: airway and ventilation, hemodynamic support, induction and sedation medication choices, transport decisions, and the traits of an ideal receiving center.

Replantation versus revision of amputated fingers in patients air-transported to a level 1 trauma center

PURPOSE

To assess the rate of replantation versus revision of amputated fingers in patients air-transported to a tertiary care hand trauma center.

METHODS

We included 40 consecutive subjects (70 digits) who were transported via air after digit(s) amputation distal to the metacarpophalangeal joint. The primary outcome measure was type of surgery (attempted replantation vs revision of the amputation). Data were collected prospectively.

RESULTS

We identified 3 groups of patients. In group 1 (15 patients, 23 digits), replantation of one or more digits was attempted. In group 2 (6 patients, 8 digits), replantation was not elected. In group 3 (19 patients, 39 digits), no digits were suitable for replantation. The mean age was 36.2 years (range, 5-69 years) and mean time of transport was 5.15 hours (range, 1-24 hours). Mechanisms of finger injury were crush (n = 34), followed by clean cut (n = 15), avulsion/crush (n = 15), and gunshot (n = 6). No significant differences were found between groups for age or time elapsed from injury to hospital arrival. Most patients (n = 25; 65%) transported via air did not undergo replantation surgery. Injury characteristics (n = 18 patients, 72%) were the main reason not to replant. The most common reason for the refusal of replantation was inability to return to work immediately. The most common reasons for surgeon's decision to not to replant were single digit amputations proximal to flexor digitorum superficialis attachment (7 patients), and crush/avulsion type injuries (7 patients), followed by health status and age (5 patients).

CONCLUSIONS

This study shows that a considerable portion of patients transported via air do not undergo replantation surgery. Further studies are needed to establish whether this is an overused service.

The UK helicopter ambulance tasking study

INTRODUCTION

Helicopter ambulances are a scarce and expensive resource and their use carries significant risk for crew and patients.

AIMS

To establish and compare the tasking criteria, dispatch arrangements and crew configuration for all helicopter ambulance services in the United Kingdom.

METHODS

Structured telephone interview of all helicopter ambulance services in the United Kingdom.

RESULTS

Replies were received from all 16 UK air ambulance services. Crew configuration varies between services. Nine services had paramedic only crew, 3 had physician/paramedic crew and 4 had a paramedic crew with variable physician input. Only 2 of the 16 services used a paramedic in the dispatch process. There were 67 different tasking criteria used for air ambulance dispatch across all air ambulances with a range from 4 to 23 for individual air ambulance services.

CONCLUSION

Given the financial burden and physical risk of air ambulance use, there should be a more standardised approach to the tasking, dispatch and crew configuration of air ambulances in the UK.

On-site hospital helipads: resource document for the NAEMSP position paper on on-site hospital helipads

The purpose of this article is to address the question of helipad location for hospitals using helicopter emergency medical services (HEMS). A helipad is defined as off-site, or remote, if a ground ambulance is required for patient transport between the helicopter and the hospital's patient care area. On-site helipads are those for which no ground ambulance transport is required between the hospital and the helicopter. The article describes the attributes of on-site helipads, which include elimination of the inherent risks of additional patient transfers, enhanced availability of emergency medical services (EMS) resources that would otherwise be used for extra transfer, and decreased time to arrival at the receiving treatment site. It is acknowledged that helipad placement decisions are informed by non-patient care issues and a paucity of research. Nevertheless, when the choice is viewed from a patient care perspective, there is a clear preference for on-site helipad location.

What risk managers should know about air medical patient transport

The use of air medical services (AMS) has become an essential component of the healthcare system. Appropriately used air medical critical care transport can save lives and reduce the cost of healthcare. It does so by minimizing the time the critically ill and injured spend out of a hospital, by bringing more medical capabilities to the patient than are normally provided by ground emergency medical services, and by helping get the patient to the appropriate specialty care quickly. Risk managers should be aware of the everyday decisions made in critical care transport to ensure the most appropriate utilization of resources to benefit the patient.

EMS andEmergency Department Physician Triage:

BACKGROUND

Many trauma patients who are not severely injured arrive at trauma centers via helicopter emergency medical services (HEMS).

OBJECTIVE

To compare the injury severity of patients sent to trauma centers by HEMS from community emergency departments (EDs) with the injury severity of those triaged by prehospital providers to HEMS directly from accident scenes.

METHODS

All records were reviewed from trauma-related missions during 1997for a single HEMS system, extracting information on location, time of day, patient age and gender, mechanism of injury, initial vital signs, Revised Trauma Score (RTS), and the extent of care required during transport. These records were then matched with outcome information routinely supplied to the HEMS system by affiliated trauma centers. Information from patients flown directly from scenes was then compared with that for patients flown from community EDs.

RESULTS

Information was obtained for 658 patients flown from scenes and 345 flown from community EDs. There were similar proportions of patients in the two groups, with Injury Severity Scale (ISS) scores less than 6 (11.0% vs. 13.5%), between 6 and 14 (47.0% vs. 49.3%), and greater than 15 (42.0% vs. 37.1%); these were not statistically different (p > 0.05). There was also no significant difference between the groups in the RTS, mean ISS score, intensive care unit length of stay, hospital length of stay, or disposition.

CONCLUSIONS

Scene and interhospital HEMS trauma missions in this system involve patients of similar injury severities. Prehospital providers may triage trauma patients to HEMS transport with proficiency similar to that of community ED physicians.

Air Medical Transport of Trauma Patients

This report reviews the current status of air medical transportation of trauma patients. Aspects reviewed include patient care, dispatch, safety, and possible future directions in air medical patient care.

Helicopter emergency medical services and stroke care regionalization: measuring performance in a maturing system

This study retrospectively analyzed 123 patients undergoing helicopter emergency medical services transport for ischemic stroke (ischemic cerebrovascular accident) to the Massachusetts General Hospital during 2000-2004. To assess for system improvements over time, data were analyzed between the 2 consecutive 30-month periods comprising the 5-year study. Patients transported during the latter 30 months were transported from lesser distances (P = .002), were more likely to be younger than 65 years (P = .005), and were more likely to have documented symptom onset time (P = .03) and National Institutes of Health Stroke Scale (odds ratio, 3.6; 95% confidence interval, 1.7-7.6; P = .001). Time end points analysis found no significant improvements in any intervals compared across the 2 study eras. Age older than 65 years was the only covariate associated with a more rapid arrival at the Massachusetts General Hospital (odds ratio, 2.4; 95% CI, 1.1-5.4; P = .03). This study of our stroke transport system identified both areas of good performance and also areas for focusing further improvement efforts.

Medically appropriate use of helicopter EMS: the mission acceptance/triage process

INTRODUCTION

Appropriate use of helicopter emergency medical services (HEMS) ensures the maximum impact of a limited resource on improved health outcomes. Overtriage increases real and opportunity costs and may unjustifiably expose the program to small but inherent safety risks. The purpose of this study is to describe the mission acceptance process for an integrated, provincially based HEMS program and determine its utilization patterns.

METHODS

This is a retrospective review of patient care and administrative databases. All missions were reviewed to determine whether they were medically appropriate. "Appropriateness" was defined a priori as requiring admission to a critical care unit, death during transportation or in first 24 hours, or in the case of trauma, an injury severity scale (ISS) score > or = 12. Overtriage was defined as not meeting these a priori definitions.

RESULTS

Five hundred eighty-four missions were reviewed from March 31, 2003 through December 31, 2004. Our mission acceptance process consists of three distinct but complementary phases: ongoing outreach education, scanning by dispatchers in an integrated dispatch center, and a clinician to online physician discussion about each case. The overall overtriage rate was 13.1%.

CONCLUSION

The rate of medically appropriate missions in this system is relatively high. Prospective research is required to improve HEMS triage systems.

Helicopter Scene Transport of Trauma Patients with Nonlife-Threatening Injuries: A Meta-Analysis

BACKGROUND

Helicopters have become a major part of the modern trauma care system and are frequently used to transport patients from the scene of their injury to a trauma center. While early studies reported decreased mortality for trauma patients transported by helicopters when compared with those transported by ground ambulances, more recent research has questioned the benefit of helicopter transport of trauma patients. The purpose of this study was to determine the percentage of patients transported by helicopter who have nonlife-threatening injuries.

METHODS

A meta-analysis was performed on peer-review research on helicopter utilization. The inclusion criteria were all studies that evaluated trauma patients transported by helicopter from the scene of their injury to a trauma center with baseline parameters defined by Injury Severity Score (ISS), Trauma Score (TS), Revised Trauma Score (RTS), and the likelihood of survival as determined via Trauma Score-Injury Severity Score (TRISS) methodology.

RESULTS

There were 22 studies comprising 37,350 patients that met the inclusion criteria. According to the ISS, 60.0% [99% confidence interval (CI): 54.5-64.8] of patients had minor injuries, According to the TS, 61.4% (99% CI: 60.8-62.0) of patients had minor injuries. According to TRISS methodology, 69.3% (99% CI: 58.5-80.2) of patients had a greater than 90% chance of survival and thus nonlife-threatening injuries. There were 25.8% (99% CI: -1.0-52.6) of patients discharged within 24 hours after arrival at the trauma center.

CONCLUSIONS

The majority of trauma patients transported from the scene by helicopter have nonlife-threatening injuries. Efforts to more accurately identify those patients who would benefit most from helicopter transport from the accident scene to the trauma center are needed to reduce helicopter overutilization.

Auto launch/early activation: a survey of AAMS members and literature review

BACKGROUND

Rapid access to definitive care is a fundamental tenet of trauma care and forms the basis for current emergency medical and trauma systems. Helicopters offer expedited transport to trauma centers and can deliver advanced practice personnel to the scene of injury, but many systems do not dispatch air medical crews until after assessment by ground providers.

OBJECTIVES

Here we report data from the AAMS Auto Launch Survey and perform a literature review.

METHODS

A 7-question survey was developed by the AAMS Research Committee and approved by the board. An invitation to participate in the survey was sent by electronic mail to all current members. A link to an online survey was included. Results were presented descriptively. Some respondents were willing to share auto launch protocols, which were categorized into patient-related factors, event-related factors, and geographic considerations.

RESULTS

A total of 86 usable responses were recorded, which represented about a third of the 240 total AAMS members. Of these, 38 respondents (44.2%) routinely use auto launch. Just over half of those using early activation reported using a combination of event- and patient-related considerations; most also incorporating geographic criteria. About one-third of respondents auto launch only at the request of ground personnel, and about one-quarter use geographic criteria alone. Threshold distances ranged from 20 to 25 miles or 20 to 30 minutes by ground.

CONCLUSIONS

About half of respondents routinely use auto launch, although protocols are not consistent. Auto launch appears to offer a mechanism for decreasing EMS response times, but additional research is needed to help define optimal dispatch criteria.

The 2003 Air Medical Leadership Congress: findings and recommendations

To address important concerns facing the air medical community, 149 air medical transport leaders, providers, consultants, and experts met September 4-6, 2003, in Salt Lake City, Utah, for a 3-day summit-the Air Medical Leadership Congress: Setting the Health Care Agenda for the Air Medical Community. Using data from a Web-based survey, top air medical transport issues were identified in four core areas: safety, medical care, cost/benefit, and regulatory/compliance. This report reviews the findings of previous congresses and summarizes the discussions, findings, recommendations, and proposed industry actions to address these issues as set forth by the 2003 congress participants.