The utility of helicopter transport of trauma patients from the injury scene in an urban trauma system

Factors Influencing Outcomes of Trauma Patients Transferred in Trauma Systems by Air or Ground Ambulance: A Systematic Review

OBJECTIVES

This systematic review aims to determine the effectiveness of ambulance transportation versus helicopter transportation on mortality for trauma patients.

METHODS

A systematic review of published and unpublished databases (to August 2023) was performed. Studies, reporting mortality, for people who experienced trauma and were transported to a trauma unit by ambulance or helicopter were eligible. The Newcastle-Ottawa scale was employed to evaluate study quality.

RESULTS

Of the 7,323 studies screened, 63 met the inclusion criteria. Thirty-two percent of these studies included patients with diverse injury types, while nine studies included patients across all age groups. The majority (92%) of the included data were retrospective in nature. Eighteen studies (28.57%) achieved the highest score on the Newcastle-Ottawa scale suggesting high-quality evidence. Seven studies examining 24-h mortality reported variable findings. Eighteen studies reported mortality without exact time points through adjusted analyses, 17 favored air transport. Air transport showed an advantage across all subgroups in the adjusted data, while the unadjusted data presented relatively similar outcomes between the two modes of transport.

CONCLUSIONS

This systematic review found that adjusted analyses consistently favored air transport over ground transport. Unadjusted analyses showed no significant difference between the two modes of transport, except in specific subgroups. Further subgroup analyses revealed notable disparities between the two modalities, suggesting that these differences may be influenced by multiple factors. These findings highlight the need for further research to clarify the true impact of transport modality on trauma outcomes.

Appropriate Air Medical Services Utilization and Recommendations for Integration of Air Medical Services Resources into the EMS System of Care: A Joint Position Statement and Resource Document of NAEMSP, ACEP, and AMPA

Air medical services involves providing medical care in transit while using either fixed wing (airplane) or rotor wing (helicopter) aircraft to move patients between locations. The modern use and availability of air medical services has expanded access to various health system resources, including specialty care. While this is generally beneficial, such expansion has also contributed to the complexity of health care delivery systems.(1, 2) Since the publication of the 2013 joint position statement Appropriate and Safe Utilization of Helicopter Emergency Medical Services,(3) research has shown that patient benefit is gained from the clinical care capabilities of air medical services independent of potential time saved when transporting patients.(4-6) Because the evidence basis for utilization of air medical services continues to evolve, NAEMSP, ACEP, and AMPA believe that an update regarding the appropriate utilization of air medical services is warranted, and that such guidance for utilization can be divided into three major categories: clinical considerations, safety considerations, and system integration and quality assurance considerations.

Identifying causes of delay in interfacility transfer of patients by air ambulance

OBJECTIVES

Population density can limit the level of care that can be provided in local facilities in Ontario, and as such, patients with severe illnesses often require interfacility transfers to access specialized care. This study aimed to identify causes of delay in interfacility transport by air ambulance in Ontario.

METHODS

Causes of delay were identified by manual review of electronic patient care records (ePCRs). All emergent interfacility transfers conducted by Ornge, the sole provider of air-based medical transport in Ontario, between January 1, 2016 and December 31, 2016 were included. The ePCRs were reviewed if they met one or more of the following: (1) contained a standardized delay code; (2) contained free text including "delay", "wait", or "duty-out"; (3) were above the 75th percentile in total transport time; or (4) were above the 90th percentile in time to bedside, time at the sending hospital, or time to receiving facility.

RESULTS

Our search strategy identified 1,220 ePCRs for manual review, which identified a total of 872 delays. Common delays cited included aircraft refueling (234 delays), waiting for land emergency medical service (EMS) escort (146), and staffing- or dispatch-related issues (124). Other delays included weather/environmental hazards (43); mechanical issues (36); and procedures, imaging, or stabilization (80).

CONCLUSIONS

Some common causes of interfacility delay are potentially modifiable: better trip planning around refueling and improved coordination with local EMS, could reduce delays experienced during interfacility trips. To better understand causes of delay, we would benefit from improved documentation and record availability which limited the results in this study.

Transferred Patients by Fars Province's Helicopter Emergency Medical Service (HEMS); A 2-Years Cross-Sectional Study in Southern Iran

Objective:

To investigate the patients transferred by helicopters, as well as an emergent medical services that were performed for them.

Methods:

In this retrospective cross-sectional study, all patients who were transferred by Fars province of Helicopter Emergency Medical Services (HEMS) to Shiraz hospitals, southern Iran (March 2017-March 2019) were investigated. Patients’ information was collected and analyzed includes age, gender, dispatch reason, trauma mechanisms, take hold of emergent medical services, as well as the air transportation time, time between dispatch from the origin hospital and starting the procedures, and patients’ outcome.

Results:

Eighty-three patients were enrolled with the mean±SD age of 36.9±19.47 years that 75.9% had trauma (p<0.0001). Mental status deterioration (25.3%) was the most dispatched indications. The mortality rate was 13.25% totally (11.11% in traumatic vs. 10% in non-traumatic). The mean±SD of air transportation time was significantly lower than ground transportation in both traumatic (p=0.0013) and non-traumatic (p<0.0001) patients. Also, the mean±SD of time between dispatch from the origin hospital and starting the procedures was statistically lower in air transportation in both traumatic (p=0.0028) and non-traumatic (p=0.0017) patients.

Conclusion:

Most of the patients transferred by HEMS were traumatic. The air transportation time as well as the time between dispatches from the origin hospital to the starting of the procedures were significantly lower in HEMS in comparison with ground transportation for both traumatic and non-traumatic patients.

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.

Transport Time and Mortality in Critically Ill Patients with Severe Traumatic Brain Injury

PURPOSE

Severe traumatic brain injury (TBI) is a major cause of morbidity and mortality in critically ill patients. Pre-hospital care and transportation time may impact their outcomes.

METHODS

Using the British Columbia Trauma Registry, we included 2,860 adult (≥18 years) patients with severe TBI (abbreviated injury scale head score ≥4), who were admitted to an intensive care unit (ICU) in a centre with neurosurgical services from January 1, 2000 to March 31, 2013. We evaluated the impact of transportation time (time of injury to time of arrival at a neurosurgical trauma centre) on in-hospital mortality and discharge disposition, adjusting for age, sex, year of injury, injury severity score (ISS), revised trauma score at the scene, location of injury, socio-economic status and direct versus indirect transfer.

RESULTS

Patients had a median age of 43 years (interquartile range [IQR] 26-59) and 676 (23.6%) were female. They had a median ISS of 33 (IQR 26-43). Median transportation time was 80 minutes (IQR 40-315). ICU and hospital length of stay were 6 days (IQR 2-12) and 20 days (IQR 7-42), respectively. Six hundred and ninety-six (24.3%) patients died in hospital. After adjustment, there was no significant impact of transportation time on in-hospital mortality (odds ratio 0.98, 95% confidence interval 0.95-1.01). There was also no significant effect on discharge disposition.

CONCLUSIONS

No association was found between pre-hospital transportation time and in-hospital mortality in critically ill patients with severe TBI.

Predictors of Inappropriate Helicopter Transport

Background

Helicopter transport (HT) is an efficient, but costly, means for injured patients to receive life-saving, definitive trauma care. Identifying the characteristics of inappropriate HT presents an opportunity to improve the utilization of this finite medical resource.

Methods

Trauma registry records of all HT for a 3-year period (2016-2018) to an urban Level I trauma center were reviewed. HT was defined as inappropriate for patients who were discharged home from the emergency department or had a hospital length of stay <1 day, and who were discharged alive. Chi-square analysis and Student’s t-test were used for univariate analysis. Predictors with a P value of less than .15 were subject to binary logistic regression analysis. A P value ≤.05 was considered significant.

Results

There were 713 patients who received HT during the study period. One-hundred and forty-eight (20.8%) patients met the criteria as an inappropriate HT. In univariate analysis, Glasgow Coma Scale >8, Shock Index <0.9, and fall mechanism were found to be significantly associated with inappropriate HT. Age >55 was found to be associated with an appropriate HT. The average Injury Severity Score of the inappropriate HT group was 3.86 (±3.85) compared with 16.80 (±11.23) ( P = .0001, Student’s t-test).

Discussion

Our findings suggest that there are evidence-based predictors of patients receiving inappropriate HT. Triage of HT using these predictors has the potential to decrease unnecessary deployments and reduce health care costs.

Trauma system resource preservation: A simple scene triage tool can reduce helicopter emergency medical services overutilization in a state trauma system

BACKGROUND

Helicopter emergency medical services improve survival in some injured patients but current utilization leads to significant overtriage with considerable numbers of transported patients discharged home from the emergency department or found to have non-time-sensitive injuries. Current triage models for utilization are complex and untested.

METHODS

Data from a state trauma registry were reviewed from 1987 to 1993 and from 2013 to 2015 and compared. Data from 2013 to 2015 were analyzed for field information found to influence mortality and a model for low mortality-risk patients designed.

RESULTS

Indexed to population, a major increase in numbers of injured patients transported directly to designated trauma centers (39.849-167.626/100,000/year) occurred with an increased portion transported by helicopter emergency medical services from 7.28% to 9.26%. A simple triage tool to predict low mortality rates was designed utilizing results from logistic regression. Nongeriatric adult patients (age, 16.0-69.9 years) with a blunt injury mechanism, normal Glasgow Coma Scale motor score, pulse rate of 60 bpm to 120 bpm and respiratory rate of 10 breaths per minute to 29 breaths per minute are at low risk for mortality. Cost for helicopter transportation was substantially higher than ground transportation based on available data. Cost differentials in transport mode increased patient financial risk when helicopter transportation was utilized.

CONCLUSION

Implementing a simple decision tool designating nongeriatric adult patients with a blunt injury mechanism, normal Glasgow Coma Scale motor score, systolic blood pressure greater than 90 mm Hg, pulse rate of 60 bpm to 120 bpm, and respiratory rate of 10 breaths per minute to 29 breaths per minute to ground transportation would result in substantial savings without an increase in mortality and reduce risk of patient financial harm.

LEVEL OF EVIDENCE

Prognostic/Epidemiological study, level IV. Economic and value based evaluation, level IV.

Defining geographic emergency medical services coverage in trauma systems

BACKGROUND

Geographic distribution of trauma system resources including trauma centers and helicopter bases correlate with outcomes. However, ground emergency medical services (EMS) coverage is dynamic and more difficult to quantify. Our objective was to evaluate measures that describe ground EMS coverage in trauma systems and correlate with outcome.

METHODS

Trauma system resources in Pennsylvania were mapped. Primary outcome was county age-adjusted transportation injury fatality rate. Measures of county EMS coverage included average distance to the nearest trauma center, number of basic life support and advanced life support units/100 square miles, distance differential between the nearest trauma center and nearest helicopter base, and nearest neighbor ratio (dispersed or clustered geographic pattern of agencies). Spatial-lag regression determined association between fatality rates and these measures, adjusted for prehospital time, Injury Severity Score, and socioeconomic factors. Relative importance of these measures was determined by assessing the loss in R value from the full model by removing each measure. A Geographic Emergency Medical Services Index (GEMSI) was created based on these measures for each county.

RESULTS

Median fatality rate was higher in counties with fewer trauma system resources. Decreasing distance to nearest trauma center, increasing advanced life support units/100 square miles, greater distance reduction due to helicopter bases, and dispersed geographic pattern of county EMS agencies were associated with lower fatality rates. The GEMSI ranged from -6.6 to 16.4 and accounted for 49% of variation in fatality rates. Adding an EMS agency to a single county that produced a dispersed pattern of EMS coverage reduced predicted fatality rate by 6%, while moving a helicopter base into the same county reduced predicted fatality rate by 22%.

CONCLUSION

The GEMSI uses several measures of ground EMS coverage and correlates with outcome. This tool may be used to describe and compare ground EMS coverage across trauma system geographies, as well as help optimize the geographic distribution of trauma system resources.

LEVEL OF EVIDENCE

Ecological study, level IV.

Competitive advantage gained from the use of helicopter emergency medical services (HEMS) for trauma patients: Evaluation of 1724 patients

OBJECTIVES

The aim of the study was to analyze helicopter emergency medical service (HEMS) in comparison to EMS, in respect to patient's mortality and morbidity.

DESIGN

From a cohort of traumatized patients (n = 1724) prospectively enrolled in the German trauma registry (DGU-R) at Frankfurt University Hospital from 2009 to 2013, 1646 could be analyzed for in-hospital mortality and short-term outcome (GOS) at discharge and compared between HEMS and EMS.

MEASUREMENTS AND MAIN RESULTS

129 patients (7.8%) died in the hospital. Unadjusted mortality was significantly lower in the HEMS group compared to EMS (p = 0.001). In a multiple logistic regression analysis after adjustment of variables including reanimation and age as the strongest predictors, in-hospital mortality was significantly reduced in HEMS (p = 0.014, OR = 0.21). Further predictors in the multiple logistic regression analysis were GCS > = 8 (p = 0.001), RRsys (p < 0.001), ISS at Head/Neck > = 3 (p = 0.003), and total ISS > = 9 (p < 0.001). Total rescue time and on scene time were associated with mortality (p < 0.001) but not included in the multiple logistic regression model. Without adjustment, short-term outcome (GOS) was significantly improved (p = 0.014). In a linear model, after adjusting for multiple variables including age, ISS Head/Neck > = 3, ISS Extremities > = 3, GCS > = 8, and RRsys as the strongest predictors (p < 0.001), the association remained significant (p = 0.043). Further predictors in the multiple linear regression analysis were total ISS > = 9 (p = 0.002), ISS abdomen (p = 0.001), and ISS Chest (p = 0.011).

CONCLUSIONS

A significant improvement for in-hospital survival for HEMS could be demonstrated. Especially in Germany, with a high number of secondary call outs (about 44%) after EMS has already reached the traumatized patient, HEMS must be the first choice for severely injured trauma patients. Dispatch criteria for immediate alarm of HEMS are recommended under practical considerations.

Current Status of helicopter emergency medical services in China: A bibliometric analysis

BACKGROUND

After nearly 20 years of development, China has realized some achievements in helicopter emergency medical services (HEMS). The purpose of this article is to introduce and evaluate the development and characteristics of HEMS in China by collecting and analyzing relevant literature and, in so doing, help this vital service to further develop.

METHOD

We conducted a Pubmed, Medline, Embase, ScienceDirect, Wanfang, CNKI, and VIP search of the literature on HEMS of China published between January 1950 and April 2017. The title, author name, number of authors, publishing date, country or region of origin, institution, type of article, study topic, funding source, and level of evidence of each article were recorded and analyzed.

RESULTS

There were 41 papers included in the analysis. All articles were published in Chinese. The selected articles were published between 2002 and 2017. The 41 articles originated from China, but 7 different regions were represented: East China (n = 14), followed by North China (n = 12), Central China (n = 8), Southwest China (n = 3), South China (n = 2), and Northwest China (n = 2). The articles included 18 clinical studies, 12 reviews, and 11 clinical guidelines. Among these, 22 articles were from public hospitals; 18 were from military units and 1 came from a private hospital. One article from the public hospitals was funded by public foundations (4.5%); 11 articles from the army units received support from Army funding (61.1%). Compared with the public and private hospitals, articles from military units were more likely to receive financial support (χ = 15.7 P <.01). All the articles were assigned a level of evidence from 1 to 5. Level 5 (78.0%) was the most frequent level of evidence. There were 7 studies at level 4. Only 2 articles were assigned to level 3. There were no articles at levels 1 or 2.

CONCLUSIONS

China's HEMS is a relatively new service. Its level of development is low, interregional development is uneven, and cooperation has been insufficient. We need to strengthen capital investment and develop a unified guideline to further enhance the development of HEMS in China.

Is It Safe to Fly Patients with Penetrating Trauma in a Rural State?

BACKGROUND

There is limited data pertaining to the triage and transportation of patients with penetrating trauma in rural states. Large urban trauma centers have found rapid transport to be beneficial even when done by nonemergency medical staff. However, there is limited application to a rural state with only a single level 1 trauma center.

MATERIALS AND METHODS

This a retrospective observational study of 854 trauma patients transported by helicopter emergency services between 2009 and 2015 to the state's only level 1 trauma center.

RESULTS

After excluding patients with other injuries or lack of data, 854 patients underwent final analysis. Compared with penetrating trauma, blunt trauma had a significantly different chance of survival (92.0% versus 81.2%, P = 0.002) and a significantly different injury severity score (17 ± 12 versus 12 ± 9, P = 0.002). After controlling for blunt injuries, age, gender, injury severity score, tachycardia, tachypnea, hypotension, glasgow coma scale, and dispatch to hospital arrival time in multivariate analysis, blunt trauma had higher odds of survival than penetrating trauma (OR, 5.97; 95% CI, 2.52-14.12; P = <0.001 = 1). Gender, tachycardia, tachypnea, and dispatch to arrival time did not impact a patient's likelihood of survival.

CONCLUSIONS

Penetrating trauma has a higher mortality when compared with blunt trauma in Helicopter Emergency Services transported patients in a rural state. Perhaps a new algorithm in the management of penetrating trauma would include hemorrhage control at a locoregional hospital before definitive care. Further study is required to understand the exact variables that lead to a higher mortality in penetrating trauma in a rural state.

When Minutes Fly by: What is the True “Golden Hour” for Air Care?

Air transport was developed to hasten patient transport based on the “golden hour” belief that delayed care leads to poorer outcome. The primary aim of our study was to identify the critical inflection point of increased nonsurvivors on total prehospital time. This was a multicenter review of adult trauma patients transported by air between November 2014 and August 2015. Primary outcome of interest was all-cause inhospital mortality. Total helicopter emergency medical services times of nonsurvivors were plotted to visualize the distribution of prehospital time. Of 636 patients included, 71 per cent were male and 86 per cent suffered blunt trauma. Among non-survivors, mortality doubled once total helicopter emergency medical services time exceeded 30 minutes (P < 0.001). Nonsurvivors presented with significantly lower median [interquartile range (IQR)] Glasgow Coma Score compared with survivors [3 (3–13) vs 15 (12–15), respectively; P < 0.001] as well as a significantly higher median (IQR) Injury Severity Score [26 (19–41) vs 12 (5–22); P < 0.001], increased incidence of penetrating mechanism of injury [21 vs 8%; P = 0.002], and higher median (IQR) shock index [0.84 (0.63–1.06) vs 0.71 (0.6–0.87); P = 0.023]. We identified an inflection point of doubling in mortality after 30 minutes. This suggests a possible threshold effect between time and mortality in severely injured patients. Revised field criteria for determining which injured patients would most benefit from helicopter transport are needed.

Mode of Transport and Clinical Outcome in Rural Trauma: A Helicopter versus Ambulance Comparison

Helicopter Emergency Medical Services (HEMS) is presumably an effective way of patient transport in rural trauma, yet the literature addressing its effectiveness is scarce. In this study, we compared the clinical outcome of rural trauma patients between Ground Emergency Medical Services (GEMS) and HEMS transportation from the beginning of 2006 to the end of 2012. Focus was placed on identifying factors associated with survival to discharge in these patients. Over the seven-year study period, 4492 patients met the inclusion criteria with 2414 patients (54%) being transferred by GEMS and 2078 patients (46%) being transferred by HEMS. In comparison with GEMS, patients transferred by HEMS were younger men who were admitted with a higher mean Injury Severity Score and a lower mean Glasgow Coma Score (all Ps < 0.0001). HEMS patients were more frequently intubated before arrival at the trauma center (32% vs 9%, P < 0.0001) and were more frequently transferred to the operating room from the emergency department (11% vs 5%, P < 0.0001). In multivariate analysis, transfer by HEMS was associated with a significant increase in survival to discharge (odds ratio: 1.57, 95% confidence interval: 1.03–2.40, P = 0.036). Blunt injury, no intubation, and Glasgow Coma Score >8 were also associated with significantly improved odds of survival to discharge (all P < 0.0001). These findings show that although patients transferred by HEMS arrived in less favorable clinical conditions, HEMS transfer was associated with significantly higher odds of survival in rural trauma.

In by helicopter out by cab: the financial cost of aeromedical overtriage of trauma patients

BACKGROUND

Helicopter transport of injured patients is controversial and costly. This study aims to show that a complex trauma algorithm leads to significant aeromedical overtriage at substantial cost. Our secondary outcomes were to compare adjusted mortality and outcomes between air and ground transport and determine predictors of overtriage.

MATERIALS AND METHODS

A 6-y retrospective analysis was conducted of all trauma activations at a Level I center. Patients were dichotomized by transportation method as well as trauma activation criteria. Overtriage was defined as those who were discharged from the emergency department, medically admitted without injuries, or admitted to observation status only. Overtriage and associated charges were calculated for each patient cohort, and multivariate regression models were created to derive adjusted mortality rates and predictors of overtriage.

RESULTS

A total of 4218 patients were treated with 28% arriving by helicopter. Overtriage increased significantly from 51% to 77% with lower tier activation criteria (P < 0.001). Median charges for air-evacuated patients was $10,478 (versus $1008 ground). Eliminating overtriage of air patients would result in a cost savings of $1,316,036 annually. Adjusted mortality between air and ground transport was not significantly different (8.5% versus 10.9%, P = 0.548). Predictors of overtriage included decreasing age, Injury Severity Score, Head Abbreviated Injury Score, nonoperative treatment, and lower tier activation criteria.

CONCLUSIONS

Significant overtriage (52%) and unnecessary air evacuation of minimally injured patients occurs at great financial cost. Revision of trauma activation protocols may result in more judicious air transport use and significant reductions in health care costs.

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.

Helicopter EMS and rapid transport for ST-elevation myocardial infarction: The HEARTS study

Background: Helicopter emergency medical services (HEMS) and ground EMS (GEMS) are both integral parts of out-of-hospital transport systems for patients with ST-elevation myocardial infarction (STEMI) undergoing emergency transport for primary percutaneous coronary intervention (PPCI). There are firm data linking time savings for PPCI transports with improved outcome. A previous pilot analysis generated preliminary estimates for potential HEMS-associated time savings for PPCI transports. Methods: This non-interventional multicenter study conducted over the period 2012–2014 at six centers in the USA and in the State of Qatar assessed a consecutive series of HEMS transports for PPCI; at one center consecutive GEMS transports of at least 15 miles were also assessed if they came from sites that also used HEMS (dual-mode referring hospitals). The study assessed time from ground or air EMS dispatch to transport a patient to a cardiac center, through to the time of patient arrival at the receiving cardiac unit, to determine proportions of patients arriving within accepted 90- and 120-minute time windows for PPCI. Actual times were compared to “route-mapping” GEMS times generated using geographical information software. HEMS' potential time savings were calculated using program-specific aircraft characteristics, and the potential time savings for HEMS was translated into estimated mortality benefit. Results: The study included 257 HEMS and 27 GEMS cases. HEMS cases had a high rate of overall transport time (from dispatch to receiving cardiac unit arrival) that fell within the predefined windows of 90 minutes (67.7% of HEMS cases) and 120 minutes (91.1% of HEMS cases). As compared to the calculated GEMS times, HEMS was estimated to accrue a median time saving of 32 minutes (interquartile range, 17–46). The number needed to transport for HEMS to get one additional case to PPCI within 90 minutes was 3. In the varied contexts of this multicenter study, the number of lives saved by HEMS, solely through time savings, was calculated as 1.34 per 100 HEMS PPCI transports. Conclusions: In this multicenter study, HEMS PPCI transport was found to be appropriate as defined by meeting predefined time windows. The overall estimate for lives saved through time savings alone was consistent with previous pilot data and was also generally consistent with favorable cost-effectiveness. Further research is necessary to confirm these findings, but judicious HEMS deployment for PPCI transports is justified by these data.

Helicopter emergency medical rescue for the traumatized: experience in the metropolitan region of Campinas, Brazil

OBJECTIVE

To analyze the profile of patients served by the air medical rescue system in the Metropolitan Region of Campinas, evaluating: triage and mobilization criteria; response time; on-site care and transport time; invasive procedures performed in the Pre-Hospital Care (PHC); severity of patients; morbidity and mortality.

METHODS

We conducted a prospective, descriptive study in which we analyzed medical records of patients rescued between July 2010 and December 2012. During this period, 242 victims were taken to the HC-Unicamp. Of the 242 patients, 22 were excluded from the study.

RESULTS

of the 220 cases evaluated, 173 (78.6%) were male, with a mean age of 32 years. Blunt trauma was the most prevalent (207 cases - 94.1%), motorcycle accidents being the most common mechanisms of injury (66 cases - 30%), followed by motor vehicle collisions (51 cases - 23.2%). The average response time was 10 ± 4 minutes and the averaged total pre-hospital time was 42 ± 11 minutes. The mean values of the trauma indices were: RTS = 6.2 ± 2.2; ISS = 19.2 ± 12.6; and TRISS = 0.78 ± 0.3. Tracheal intubation in the pre-hospital environment was performed in 77 cases (35%); 43 patients (19.5%) had RTS of 7.84 and ISSd"9, being classified as over-triaged. Of all patients admitted, the mortality was 15.9% (35 cases).

CONCLUSION

studies of air medical rescue in Brazil are required due to the investments made in the pre-hospital care in a country without an organized trauma system. The high rate of over-triage found highlights the need to improve the triage and mobilization criteria.

It's All About Location, Location, Location: A New Perspective on Trauma Transport

OBJECTIVE

To determine the effect of aeromedical transport on trauma mortality when accounting for geographic factors.

BACKGROUND

The existing literature on the mortality benefit of aeromedical transport on trauma mortality is controversial. Studies examining patient and injury characteristics find higher mortality, whereas studies measuring injury severity find a protective effect. Previous studies have not adjusted for the time and distance that would have been traveled had a helicopter not been used.

METHODS

Retrospective analysis of an institutional trauma registry. We compared mortality among adult patients (≥15 years) transported from the scene of injury to our level I trauma center by air or ground (January 1, 2000-December 31, 2010) using univariate comparisons and multivariable logistic regression. Regression models were constructed to incrementally account for patient demographics and injury mechanism, followed by injury severity, and, finally, by network bands for drive time and roadway distance as predicted by geographic information systems.

RESULTS

Of 4522 eligible patients, 1583 (35%) were transported by air. Patients transported by air had higher unadjusted mortality (4.1% vs 1.9%, P < 0.05). In multivariable modeling, including patient demographics and type of injury, helicopter transport predicted higher mortality than ground transport (odds ratio [OR] 2.4, 95% confidence interval [CI] 1.2-4.0). After adding validated injury severity measures to the model, helicopter transport predicted lower mortality (OR 0.7, 95% CI 0.3-0.9). Finally, including geographic covariates found that helicopter transport was not associated with mortality (OR 1.1, 95% CI 0.6-2.3).

CONCLUSIONS

Helicopter transport does not impart a survival benefit for trauma patients when geographic considerations are taken into account.

Helicopter emergency medical services for adults with major trauma

BACKGROUND

Although helicopters are presently an integral part of trauma systems in most developed nations, previous reviews and studies to date have raised questions about which groups of traumatically injured people derive the greatest benefit.

OBJECTIVES

To determine if helicopter emergency medical services (HEMS) transport, compared with ground emergency medical services (GEMS) transport, is associated with improved morbidity and mortality for adults with major trauma.

SEARCH METHODS

We ran the most recent search on 29 April 2015. We searched the Cochrane Injuries Group's Specialised Register, The Cochrane Library (Cochrane Central Register of Controlled Trials; CENTRAL), MEDLINE (OvidSP), EMBASE Classic + EMBASE (OvidSP), CINAHL Plus (EBSCOhost), four other sources, and clinical trials registers. We screened reference lists.

SELECTION CRITERIA

Eligible trials included randomized controlled trials (RCTs) and nonrandomized intervention studies. We also evaluated nonrandomized studies (NRS), including controlled trials and cohort studies. Each study was required to have a GEMS comparison group. An Injury Severity Score (ISS) of at least 15 or an equivalent marker for injury severity was required. We included adults age 16 years or older.

DATA COLLECTION AND ANALYSIS

Three review authors independently extracted data and assessed the risk of bias of included studies. We applied the Downs and Black quality assessment tool for NRS. We analyzed the results in a narrative review, and with studies grouped by methodology and injury type. We constructed 'Summary of findings' tables in accordance with the GRADE Working Group criteria.

MAIN RESULTS

This review includes 38 studies, of which 34 studies examined survival following transportation by HEMS compared with GEMS for adults with major trauma. Four studies were of inter-facility transfer to a higher level trauma center by HEMS compared with GEMS. All studies were NRS; we found no RCTs. The primary outcome was survival at hospital discharge. We calculated unadjusted mortality using data from 282,258 people from 28 of the 38 studies included in the primary analysis. Overall, there was considerable heterogeneity and we could not determine an accurate estimate of overall effect.Based on the unadjusted mortality data from six trials that focused on traumatic brain injury, there was no decreased risk of death with HEMS. Twenty-one studies used multivariate regression to adjust for confounding. Results varied, some studies found a benefit of HEMS while others did not. Trauma-Related Injury Severity Score (TRISS)-based analysis methods were used in 14 studies; studies showed survival benefits in both the HEMS and GEMS groups as compared with MTOS. We found no studies evaluating the secondary outcome, morbidity, as assessed by quality-adjusted life years (QALYs) and disability-adjusted life years (DALYs). Four studies suggested a small to moderate benefit when HEMS was used to transfer people to higher level trauma centers. Road traffic and helicopter crashes are adverse effects which can occur with either method of transport. Data regarding safety were not available in any of the included studies. Overall, the quality of the included studies was very low as assessed by the GRADE Working Group criteria.

AUTHORS' CONCLUSIONS

Due to the methodological weakness of the available literature, and the considerable heterogeneity of effects and study methodologies, we could not determine an accurate composite estimate of the benefit of HEMS. Although some of the 19 multivariate regression studies indicated improved survival associated with HEMS, others did not. This was also the case for the TRISS-based studies. All were subject to a low quality of evidence as assessed by the GRADE Working Group criteria due to their nonrandomized design. The question of which elements of HEMS may be beneficial has not been fully answered. The results from this review provide motivation for future work in this area. This includes an ongoing need for diligent reporting of research methods, which is imperative for transparency and to maximize the potential utility of results. Large, multicenter studies are warranted as these will help produce more robust estimates of treatment effects. Future work in this area should also examine the costs and safety of HEMS, since multiple contextual determinants must be considered when evaluating the effects of HEMS for adults with major trauma.

Helicopter transport improves survival following injury in the absence of a time-saving advantage

BACKGROUND

Although survival benefits have been shown at the population level, it remains unclear what drives the outcome benefits for helicopter emergency medical services (HEMS) in trauma. Although speed is often cited as the vital factor of HEMS, we hypothesized a survival benefit would exist in the absence of a time savings over ground emergency medical services (GEMS). The objective was to examine the association of survival with HEMS compared with GEMS transport across similar prehospital transport times.

METHODS

We used a retrospective cohort of scene HEMS and GEMS transports in the National Trauma Databank (2007-2012). Propensity score matching was used to match HEMS and GEMS subjects on the likelihood of HEMS transport. Subjects were stratified by prehospital transport times in 5-minute increments. Conditional logistic regression determined the association of HEMS with survival across prehospital transport times strata controlling for confounders. Transport distance was estimated from prehospital transport times and average HEMS/GEMS transport speeds.

RESULTS

There were 155,691 HEMS/GEMS pairs matched. HEMS had a survival benefit over GEMS for prehospital transport times between 6 and 30 minutes. This benefit ranged from a 46% increase in odds of survival between 26 and 30 minutes (adjusted odds ratio [AOR], 1.46; 95% CI, 1.11-1.93; P < .01) to an 80% increase in odds of survival between 16 and 20 minutes (AOR, 1.80; 95% CI, 1.51-2.14; P < .01). This prehospital transport times window corresponds to estimated transport distance between 14.3 and 71.3 miles for HEMS and 3.3 and 16.6 miles for GEMS.

CONCLUSION

When stratified by prehospital transport times, HEMS had a survival benefit concentrated in a window between 6 and 30 minutes. Because there was no time-savings advantage for HEMS, these findings may reflect care delivered by HEMS providers.

Ankle Fractures and Modality of Hospital Transport at a Single Level 1 Trauma Center: Does Transport by Helicopter or Ground Ambulance Influence the Incidence of Complications?

In an era of concern over the rising cost of health care, cost-effectiveness of auxiliary services merits careful evaluation. We compared costs and benefits of Helicopter Emergency Medical Service (HEMS) with Ground Emergency Medical Service (GEMS) in patients with an isolated ankle fracture. A medical record review was conducted for patients with an isolated ankle fracture who had been transported to a level 1 trauma center by either HEMS or GEMS from January 1, 2000 to December 31, 2010. We abstracted demographic data, fracture grade, complications, and transportation mode. Transportation costs were obtained by examining medical center financial records. A total of 303 patients was included in the analysis. Of 87 (28.71%) HEMS patients, 53 (60.92%) had sustained closed injuries and 34 (39.08%) had open injuries. Of the 216 (71.29%) GEMS patients, 156 (72.22%) had closed injuries and 60 (27.78%) had open injuries. No significant difference was seen between the groups regarding the percentage of patients with open fractures or the grade of the open fracture (p = .07). No significant difference in the rate of complications was found between the 2 groups (p = 18). The mean baseline cost to transport a patient via HEMS was $10,220 + a $108/mile surcharge, whereas the mean transport cost using GEMS was $976 per patient + $16/mile. Because the HEMS mode of emergency transport did not significantly improve patient outcomes, health systems should reconsider the use of HEMS for patients with isolated ankle fractures.

The excess cost of interisland transfer of intracerebral hemorrhage patients

BACKGROUND

Currently, intracerebral hemorrhage (ICH) patients from neighbor islands are air transported to a higher-level facility on Oahu with neuroscience expertise. However, the majority of them do not receive subspecialized neurosurgical procedures (SNP) upon transfer. Hence, their transfer may potentially be considered as excess cost.

METHODS

Consecutive ICH patients hospitalized at a tertiary center on Oahu between 2006 and 2013 were studied. Subspecialized neurosurgical procedure was defined as any neurosurgical procedure or conventional cerebral angiogram. Total excess cost was estimated as the cost of interisland transfer multiplied by the number of interisland transfer patients who did not receive any SNP.

RESULTS

Among a total of 825 patients, 100 patients (12%) were transferred from the neighbor islands. Among the neighbor-island patients, 69 patients (69%) did not receive SNP, which translates to $1035000 of excess cost over an 8-year period (approximately $129375/y). Multivariable analyses showed age (odds ratio [OR], 0.95; 95% confidence interval [CI]: 0.94-0.96), lack of hypertension (OR, 1.62; 95% CI: 1.002-2.61), initial Glasgow Coma Scale (OR, 0.94; 95% CI: 0.89-0.98), lobar hemorrhage (OR, 2.74; 95% CI: 1.59-4.71), cerebellar hemorrhage (OR, 5.47; 95% CI: 2.78-10.76), primary intraventricular hemorrhage (OR, 4.40; 95% CI: 1.77-10.94), and any intraventricular hemorrhage (OR, 2.47l 95% CI: 1.53-3.97) to be independent predictors of receiving SNP.

CONCLUSION

Approximately two-thirds of ICH patients who were air transferred did not receive SNP. Further study is needed to assess the cost-effectiveness of creating a triage algorithm to optimally select ICH patients who would benefit from air transport to a higher-level facility.

The Effectiveness Evaluation of Helicopter Ambulance Transport among Neurotrauma Patients in Korea

Objective

Helicopter ambulance transport (HAT) is a highly resource-intensive facility that is a well-established part of the trauma transport system in many developed countries. Here, we review the benefit of HAT for neurosurgical patients in Korea.

Methods

This retrospective study followed neurotrauma patients who were transferred by HAT to a single emergency trauma center over a period of 2 years. The clinical benefits of HAT were measured according to the necessity of emergency surgical intervention and the differences in the time taken to transport patients by ground ambulance transport (GAT) and HAT.

Results

Ninety-nine patients were transferred to a single university hospital using HAT, of whom 32 were taken to the neurosurgery department. Of these 32 patients, 10 (31.3%) needed neurosurgical intervention, 14 (43.8%) needed non-neurosurgical intervention, 3 (9.4%) required both, and 11 (34.4%) did not require any intervention. The transfer time was faster using HAT than the estimated time needed for GAT, although for a relatively close distance (<50 km) without ground obstacles (mountain or sea) HAT did not improve transfer time. The cost comparison showed that HAT was more expensive than GAT (3,292,000 vs. 84,000 KRW, p<0.001).

Conclusion

In this Korean-based study, we found that HAT has a clinical benefit for neurotrauma cases involving a transfer from a distant site or an isolated area. A more precise triage for using HAT should be considered to prevent overuse of this expensive transport method.

Geographic information software programs' accuracy for interfacility air transport distances and time

INTRODUCTION

This study aimed to evaluate consistency/predictability of interfacility flight times (IFFTs) and accuracy of geographical information system (GIS) software packages for estimating IFFT.

METHODS

This retrospective study conducted by a program using a Bell 206 assessed the first 1000 IF transports occurring on 137 "runs" (ie, referring-receiving hospital pairings) made at least twice. GIS IFFT estimates using Google Earth™ (GE) and ArcGIS™ (AG) were compared against actual IFFT using linear regression; univariate analysis included assessment of medians with 95% binomial exact confidence intervals (CIs). Interrater agreement for GIS was assessed with κ.

RESULTS

GE and AG estimates fell, respectively, within 1 mile of actual in 136/137 runs (99%, 95% CI 96%-100%) and 130/137 runs (95%, 95% CI 90%-98%). GE- and AG-predicted IFFT strongly (P < .001) correlated with, underestimating by about 2 minutes, actual IFFT (GE: r2 0.93, coefficient 0.98, 95% CI .97-1.00; AG: r2 0.93; coefficient 0.98, 95% CI .96-1.0). GE and AG had statistically equivalent (κ > .8), "almost-perfect," interrater agreement.

CONCLUSION

IFFTs for same-run helicopter EMS transports in our rural state setting are characterized by little variability. GIS is highly accurate in predicting IF logistics, with public-domain GE performing as well as more expensive AG.

Retrospective review of injury severity, interventions and outcomes among helicopter and nonhelicopter transport patients at a Level 1 urban trauma centre

BACKGROUND

Air ambulance transport for injured patients is vitally important given increasing patient volumes, the limited number of trauma centres and inadequate subspecialty coverage in nontrauma hospitals. Air ambulance services have been shown to improve patient outcomes compared with ground transport in select circumstances. Our primary goal was to compare injuries, interventions and outcomes in patients transported by helicopter versus nonhelicopter transport.

METHODS

We performed a retrospective 10-year review of 14 440 patients transported to an urban Level 1 trauma centre by helicopter or by other means. We compared injury severity, interventions and mortality between the groups.

RESULTS

Patients transported by helicopter had higher median injury severity scores (ISS), regardless of penetrating or blunt injury, and were more likely to have Glasgow Coma Scale scores less than 8, require airway control, receive blood transfusions and require admission to the intensive care unit or operating room than patients transported by other means. Helicopter transport was associated with reduced overall mortality (odds ratio 0.41, 95% confidence interval 0.33-0.39). Patients transported by other methods were more likely to die in the emergency department. The mean ISS, regardless of transport method, rose from 12.3 to 15.1 (p = 0.011) during our study period.

CONCLUSION

Patients transported by helicopter to an urban trauma centre were more severely injured, required more interventions and had improved survival than those arriving by other means of transport.

Helicopter transport effectiveness of patients for primary percutaneous coronary intervention

BACKGROUND

For patients with ST-elevated myocardial infarction (STEMI), time to primary percutaneous coronary intervention (PCI) is an important factor in saving myocardium. Helicopter emergency medical service (HEMS) has become a vital component in regionalized cardiac care. The objective of this study is to assess the logistics of HEMS and ground EMS for interfacility transport of STEMI patients for primary PCI and to determine the effectiveness of HEMS transports in terms of the number of lives saved per 100 flights.

METHODS

This is a retrospective database and records review of interfacility transports of STEMI patients for primary PCI to a single medical center. The study period consisted of 18 months (January 2010 through June 2011).

RESULTS

Ninety-seven of 120 patients met the criteria for review. Of these, 66% were transported by HEMS. The pretransport patient handling times were similar for the HEMS and ground EMS groups. Door-to-PCI in < 120 minutes was achieved in 35.5% (11 of 31) of ground EMS and 24.2% (16 of 66) of HEMS. Patients transported by ground EMS were more likely to get to PCI in < 90 minutes (9.7%, 3 of 31). HEMS patients traveled significantly farther distances, 51 miles (IQR 43-68) than ground EMS, 37 miles (IQR 18-51). This equates to a 38% longer distance for patients transported by HEMS. An estimate of the driving time for HEMS-transported patients suggests HEMS transports saved a median of 41 minutes (IQR 33-48). The proportion of HEMS flights saving more than 30 minutes was 78.8% (95% CI 67.0-87.9%).

CONCLUSION

The results did not show a time savings for HEMS- versus ground EMS-transported patients. When estimates of time spent for ground EMS of actual HEMS transported patients are analyzed, HEMS provides a median savings of 41 minutes, with a savings of at least 30 minutes in 78.8% of the HEMS patients. Based on estimates used in this study, conservative calculations arrived at a time-based mortality effectiveness of HEMS of about 1.2 lives saved per 100 flights.

Multi-institutional Comparison of Helicopter Transfers Directly to the Operating Room versus the Pit Stop in the Emergency Department

Presented September 24, 2011, at the 92nd annual meeting of the New England Surgical Society, September 23–25, 2011, Mt. Washington, New Hampshire.

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.

Helicopter emergency medical service inTehran, Iran: a descriptive study

OBJECTIVE

The study provides descriptive information regarding missions performed by Tehran helicopter emergency medical services (HEMS) during a 1-year period.

METHODS

All patients transferred by Tehran HEMS between March 2006 and March 2007 were enrolled in this descriptive study. Based on HEMS records, information was gathered on flight time, the number of patients transferred in each flight, and mission outcomes.

RESULTS

During the 1-year study, a total of 353 patients were transported via 138 helicopter flights to 4 medical care centers in Tehran. The mean flight time, the time from the initial call until the patient was delivered to a medical facility, was 36.56 ± 18.44 minutes.

CONCLUSION

Tehran HEMS is still far from attaining optimal values, particularly regarding flight time. More efforts are needed to improve the timing as a component of care and the quality of care provided by this system.

The effect of prehospital time related variables on mortality following severe thoracic trauma

OBJECTIVES

The aims of this study is firstly to analyse the impact of prehospital time related variables on mortality, in a specific subset of HEMS patients and secondly to demonstrate any interactions between time related variables and factors taking place in the prehospital setting.

METHODS

Retrospective analysis of 688 consecutive London HEMS transfers with severe thoracic trauma and mean injury severity score (ISS) of 35, during a 9-year period (1994-2002). We have analysed the effect of the following time related variables on mortality: activation time, arrival on scene time (AoS), stay on scene time (SoS), total time (ToT), rush-hour time (RhT) and leisure-hour time (LhT). We have also investigated the interaction of the above mentioned variables with observations and interventions taken place on scene and at accident and emergency department (A&E) following adjustment for type and severity of injury. For statistical analysis the time variables were grouped into quintiles.

RESULTS

Six hundred eighty eight victims (510 males) with mean age of 38.5 ± 17.5 had total survival rate of 59.6%. The mean AoS and SoS were 11.6 ± 5.8 min and 36.6 ± 16.8 min, respectively. ToT>65 min, as in quintiles III, IV and V with mean ToT of 65.3 min, 74.9 min and 102.7 min respectively, had an influence on mortality with calculated adjusted OR of 1.37 (95%CI=0.47-3.94), 3.36 (95%CI = 1.22-9.23) and 1.43 (95%CI = 0.52-3.92) respectively with concomitant adjustment for type of injury, severity of injury, age, physiological variables on scene and on scene emergency thoracotomy (ET). ET on scene was an independent predictor for mortality (OR 3.94, 95%CI = 1.03-15.06). SoS of more than 34 min can lead to harmful changes on patients' pathophysiological status. ISS has no significant effect on AoS or SoS. RhT and LhT have no significant effect on mortality and they did not influence the AoS and SoS.

CONCLUSION

This study suggests that time related variables have a complex and heterogeneous effect on mortality. Thoracic trauma victims usually have high ISS, in such population, ToT <65 min may be associated with lower possibility of death. Neither AoS nor SoS was influenced by time of incident or severity of injury.

Is Helicopter Evacuation Effective in Rural Trauma Transport?

Helicopter transport for trauma remains controversial because its appropriate utilization and efficacy with regard to improved survival is unproven. The purpose of this study was to assess rural trauma helicopter transport utilization and effect on patient survival. A retrospective chart review over a 2-year period (2007–2008) was performed of all rural helicopter and ground ambulance trauma patient transports to an urban Level I trauma center. Data was collected with regard to patient mortality and Injury Severity Score (ISS). Miles to the Level I trauma center were calculated from the point where helicopter or ground ambulance transport services initiated contact with the patient to the Level I trauma center. During the 2-year period, 1443 rural trauma patients were transported by ground ambulance and 1028 rural trauma patients were transported by helicopter. Of the patients with ISS of 0 to 10, 471 patients were transported by helicopter and 1039 transported by ground. There were 465 (99%) survivors with ISS 0 to 10 transported by helicopter with an average transport distance of 34.6 miles versus 1034 (99.5%) survivors with ISS 0 to 10 who were transported by ground an average of 41.0 miles. Four hundred and twenty-one patients with ISS 11 to 30 were transported by helicopter an average of 33.3 miles with 367 (87%) survivors versus a 95 per cent survival in 352 patients with ISS 11 to 30 who were transported by ground an average of 39.9 miles. One hundred and thirty-six patients with ISS >30 were transported by helicopter an average of 32.8 miles with 78 (57%) survivors versus a 69 per cent survival in 52 patients with ISS > 30 who were transported by ground an average of 33.0 miles. Helicopter transport does not seem to improve survival in severely injured (ISS > 30) patients. Helicopter transport does not improve survival and is associated with shorter travel distances in less severely injured (ISS < 10) patients in rural areas. This data questions effective helicopter utilization for trauma patients in rural areas. Further study with regard to helicopter transport effect on patient survival and cost-effective utilization is warranted.

Helicopter transport: help or hindrance?

PURPOSE OF REVIEW

Traumatic injury continues to be a significant cause of morbidity and mortality in the year 2011. In addition, the healthcare expenditures and lost years of productivity represent significant economic cost to the affected individuals and their communities. Helicopters have been used to transport trauma patients for the past 40 years, but there are conflicting data on the benefits of helicopter emergency medical service (HEMS) in civilian trauma systems. Debate persists regarding the mortality benefit, cost-effectiveness, and safety of helicopter usage, largely because the studies to date vary widely in design and generalizability to trauma systems serving heterogeneous populations and geography. Strict criteria should be established to determine when HEMS transport is warranted and most likely to positively affect patient outcomes. Individual trauma systems should conduct an assessment of their resources and needs in order to most effectively incorporate helicopter transport into their triage model.

RECENT FINDINGS

Research suggests that HEMS improves mortality in certain subgroups of trauma patients, both after transport from the scene of injury and following interfacility transport. Studies examining the cost-effectiveness of HEMS had mixed results, but the majority found that it is a cost-effective tool. Safety remains an issue of contention with HEMS transport, as helicopters are associated with significant safety risk to the crew and patient. However, this risk may be justified provided there is a substantial mortality benefit to be gained.

SUMMARY

Recent studies suggest that strict criteria should be established to determine when helicopter transport is warranted and most likely to positively affect patient outcomes. Individual trauma systems should conduct an assessment of their resources and needs in order to most effectively incorporate HEMS into their triage model. This will enable regional hospitals to determine if the costs and safety risks associated with HEMS are worthwhile given the potential benefits to patient morbidity and mortality.

Incidents, accidents and fatalities in 40 years of German helicopter emergency medical system operations

CONTEXT

Currently, approximately 100 000 helicopter emergency medical service (HEMS) missions for patients are undertaken in Germany each year. Compared to the early years, risk has reduced significantly, but is still higher than commercial aviation or other airborne operations.

OBJECTIVE

The aim of the present study was to evaluate helicopter accidents and fatalities related to HEMS operations.

DESIGN

Retrospective study of HEMS accidents in Germany.

SETTING

Analysis of accidents in the published flight accident reports of the German Federal Agency for Flight Accident Investigation (40-year period from 1970 to 2009). Data were collected by telephone interview with the operators, manual search of publications and by supplemental internet information.

MAIN OUTCOME MEASURES

Data were analysed per 10 000 missions. For statistical analysis, Fisher[Combining Acute Accent]s exact test was used. A P value less than 0.05 was considered significant.

RESULTS

During the period analysed, a total of 1.698 million HEMS missions (1970 vs. 2009: 61 vs. 98 471) were flown by a mean of 50 ± 27 (1 vs. 81) helicopters. To date, missions resulted in a total of 99 accidents with a mean of 2.4 ± 1.7 accidents per year (range 0-7). The accident rate was 0.57 (0-11.4) per 10 000 missions and the fatal accident rate was 0.11 (0-0.5). Some 64% of missions did not result in any injuries to occupants, whereas 19.2% were fatal. From the accidents analysed, 43.4% were due to collision with an obstacle during landing, take-off or hovering. Landing was the phase of flight most often associated with accidents (44.4%).

CONCLUSION

The present study is the largest on HEMS accidents and the only one analysing an entire 40-year time course beginning with inception. In comparison to previous data, a significantly lower accident rate per 10 000 missions was found. Gathering data on the early years is nearly impossible, and further analysis is required to calculate the risk of fatality or identify injury patterns.

Association of direct helicopter versus ground transport and in-hospital mortality in trauma patients: a propensity score analysis

OBJECTIVES

Helicopter emergency medical services (HEMS) transport of trauma patients has been used for decades. Its use, however, is still a subject of debate, including issues such as high costs, increasing numbers of crashes, and conflicting results regarding effectiveness in reducing mortality. The aim of this study was to examine whether mode of transport (HEMS vs. ground EMS) is independently associated with mortality among trauma patients transported directly from the scene of injury to definitive care.

METHODS

All trauma patients transported directly to a Level I or Level II trauma center by either air or ground EMS over a 4-year period were selected from the Oklahoma State Trauma Registry. Multivariable logistic regression was used to develop propensity scores based on variables measured at the scene of injury. The propensity scores represented the predicted probabilities of a patient being transported by HEMS given a specific set of characteristics and were used as a composite confounding variable in subsequent models of the association of mortality and mode of transport. Along with the propensity scores, Injury Severity Scores (ISS), initial Revised Trauma Score (RTS), and distance from the trauma center were included in a Cox proportional hazards model of the association of mode of transport and 24-hour and 2-week mortality.

RESULTS

Overall, the hazard ratio (HR) for 2-week mortality in patients transported by HEMS was 33% lower (HR = 0.67, 95% confidence interval [CI] = 0.54 to 0.84) than in patients transported by ground EMS from the scene of injury, after adjustment for the propensity score and other covariates. In subanalyses, the apparent association of a reduction in the hazard of early mortality among patients transported by HEMS was most evident for patients with an RTS based on injury scene vital signs of 3 to 7 (HR = 0.61, 95% CI = 0.46 to 0.82). The point estimate of the HR was similar (HR = 0.65 95% CI = 0.34 to 1.2) in the 75% of cases who had normal vital signs at the scene of injury, although it was no longer statistically significant because crude mortality was very low (1.7%) in this group. Among those with a RTS of 3 or less at the scene, crude mortality was 58%, and mode of transport was not associated with mortality (HR = 1.02, 95% CI = 0.68 to 1.6).

CONCLUSIONS

Helicopter EMS transport was associated with a decreased hazard of mortality among certain patients transported from the scene of injury directly to definitive care. Refinements in scene triage and transport guidelines are needed to more effectively select patients that may benefit from HEMS transport from those unlikely to benefit.

Factors associated with trauma center use for elderly patients with trauma: a statewide analysis, 1999-2008

OBJECTIVES

To estimate the likelihood of trauma center admission for injured elderly patients with trauma, determine trends in trauma center admissions, and identify factors associated with trauma center use for elderly patients with trauma.

DESIGN

Retrospective analysis.

SETTING

Acute care hospitals in California.

PATIENTS

All patients hospitalized for acute traumatic injuries during the period from January 1, 1999, to December 31, 2008 (n = 430,081). Patients who had scheduled admissions for nonacute or minor trauma were excluded.

MAIN OUTCOME MEASURE

Likelihood of admission to level I or II trauma center was calculated according to age categories after adjusting for patient and system factors.

RESULTS

Of 430,081 patients admitted to California acute care hospitals for trauma-related diagnoses, 27% were older than 65 years. After adjusting for demographic, clinical, and system factors, compared with trauma patients aged 18-25 years, the odds of admission to a trauma center decreased with increasing age; patients aged 26-45 years had lower odds (odds ratio [OR], 0.75; 95% confidence interval [CI], 0.71-0.80) of being admitted to a trauma center for their injuries than did patients 46-65 years of age (OR, 0.57; 95% CI, 0.54-0.60), patients 66-85 years of age (OR, 0.35; 95% CI, 0.30-0.41), and patients older than 85 years (OR, 0.30; 95% CI, 0.25-0.36). Similar patterns were found when stratifying the analysis by trauma type and severity. Living more than 50 miles away from a trauma center (OR, 0.03; 95% CI, 0.01-0.06) and lack of county trauma center (OR, 0.17; 95% CI, 0.09-0.35) were also predictors of not receiving trauma care.

CONCLUSION

Age and likelihood of admission to a trauma center for injured patients were observed to be inversely proportional after controlling for other factors. System-level factors play a major role in determining which injured patients receive trauma care.

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.