The impact of helicopter emergency medical service on acute ischemic stroke patients: A systematic review

Association between helicopter medical services for pediatric trauma patients and mortality: Systematic review and meta-analysis

BACKGROUND

Helicopter emergency medical services (HEMS) have become widespread around the world. However, previous studies of the influence of HEMS on mortality were limited to adult patients only and showed inconsistent and heterogeneous results. This study aimed to examine the association between HEMS and mortality among pediatric emergencies compared to ground emergency medical service (GEMS).

METHODS

We searched relevant databases (MEDLINE, EMBASE, The Cochrane Central Register of Controlled Trials) and included articles in any language. The most recent search was on January 4th, 2024. We included prospective observational cohort studies or clinical trials that compared HEMS with GEMS in pediatric patients. We excluded any study that did not compare two or more groups of participants. Two pairs of researchers blindly screened studies and evaluated risk of bias using the Risk of Bias in Nonrandomized Studies of Interventions tool. We conducted this systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. Data were extracted by four independent reviewers. We calculated the odds ratio using the random-effects model. The primary outcome was mortality.

RESULTS

Our search strategy yielded 1454 results. Of these, seven observational studies met our eligibility criteria; no RCT met the criteria. All studies targeted trauma patients only. HEMS was associated with lower mortality (Odds ratio 0.66, 95 % CI 0.59 to 0.74). Inconsistency between trials was determined to be low due to low heterogeneity (I2 = 0 %). In a subgroup analysis conducted with and without physicians on the HEMS staff, we found no significant differences (I2 = 0 %, p = 0.71).

CONCLUSION

Our systematic review and meta-analysis, which was limited to trauma pediatric trauma patients, revealed that HEMS deployment correlated with decreased mortality. Further research is necessary to more effectively measure the potential influence and applicability of HEMS for pediatric emergencies.

AHN LifeFlight, 45 Years in the Making: Current Condition and Capabilities of Air Medical Transport

In Pittsburgh, Pennsylvania, the skies have become a battleground against time in a world where every second counts. Since its inception in 1978, a revolution has occurred in emergency medical services, with LifeFlight Helicopters soaring to new heights in emergency treatment and transport. This article will explore the transformation of helicopter emergency medical services through the decades, where every rotor blade spins with a mission to save lives and rewrite the rules of survival. Allegheny Health Network's LifeFlight is a rotor-wing (helicopter) aeromedical transport service that provides rapid emergent transport for critically ill and injured persons. The program hub of operations is primarily in Western Pennsylvania. Since its inception in 1978, the program has grown and transformed into the sophisticated, highly technical, expanded scope of practice, critical care transport service it is today. The crews spend a significant portion of clinical care focusing on preparing the patient to survive the transport and ensure stability during transit; this phase of transport is equally crucial as the patient care during the actual flight. This article introduces the evolution and innovations that LifeFlight's medical crews and aviation practices have undergone since the program started.

Air Medical Transport for Acute Ischemic Stroke Patients: A Retrospective Cohort Study of National Trends Over an 8-Year Period

OBJECTIVE

Optimal management of ischemic stroke is time dependent. An understanding of patterns of air medical transport may identify disparities that could affect patient care.

METHODS

In this 8-year (2007-2014) observational, retrospective, cohort study, we abstracted a 20% national sample of Medicare data from patients ≥ 66 years of age hospitalized with a primary diagnosis of acute ischemic stroke who presented to the emergency department by ambulance (air or ground).

RESULTS

Among 149,751 hospitalized stroke patients who arrived by ambulance, the mean age was 81.6 years (standard deviation = 8.0 years), 62.1% were female (n = 93,007), and 86.3% were White (n = 129,268). Of these, 5,534 patients (3.7%) used any form of air ambulance. Air ambulance use (2007: 2.5%, 2014: 4.9%; P < .001) and arrival at certified stroke centers (2007: 40.3%, 2014: 63.2%; P < .001) increased over time. Air ambulance use was less likely among older patients (76-85 years and >85 years vs. 66-75 years; odds ratio [OR] = 0.68; 95% confidence interval [CI], 0.64-0.72 and OR = 0.34; 95% CI, 0.32-0.37, respectively) and all racial minorities except American Natives (OR = 2.07; 95% CI, 1.57-2.73) and more likely among sicker patients (Charlson Comorbidity Index ≥ 2 vs. 1, OR = 1.23; 95% CI, 1.09-1.38) and rural residents (OR = 1.34; 95% CI, 1.09-1.64). After adjustment for covariates, air ambulance use was associated with higher odds of thrombolysis (adjusted OR = 2.57; 95% CI, 2.38-2.79).

CONCLUSION

Air ambulance use is independently associated with increased thrombolysis use for stroke, but disparities exist in both air ambulance and thrombolysis use. Further research into underlying causes for these disparities would be beneficial for systems and public health-based interventions for improving outcomes for ischemic stroke.

The Development of Helicopter Emergency Medical Services in the Republic of Ireland

Helicopter emergency medical services (HEMS) have formed an integral component of the Irish health care system for the past decade; yet, the factors leading their commencement, their evolutions over this time, and the current model of service delivery have not been widely published. Aeromedical service provision may vary significantly from country to country and may also vary regionally within countries. A health system's necessities; capacity and maturity; the level of state, corporate, private, or community investment; and the capacity of the contracted service provider are all factors that influence the service provision. This research article describes the historic factors leading to a military and health system collaboration to HEMS during an era of health care reform. Over the past decade, the Irish health system has undergone significant reconfiguration and centralization of services, leading to increased demands on emergency medical ground and air medical services. Future advancements in aeromedical service provision require an innate understanding of the current model. This article adds to the knowledge base, informs policy makers, and supports decision making surrounding HEMS provision and the potential to explore military and health system collaborations and enhanced overall service provision.

Prehospital Stroke Care Part 1: Emergency Medical Services and the Stroke Systems of Care

Acute stroke care begins before hospital arrival, and several prehospital factors are critical in influencing overall patient care and poststroke outcomes. This topical review provides an overview of the state of the science on prehospital components of stroke systems of care and how emergency medical services systems may interact in the system to support acute stroke care. Topics include layperson recognition of stroke, prehospital transport strategies, networked stroke care, systems for data integration and real-time feedback, and inequities that exist within and among systems.

Community socioeconomic and urban-rural differences in emergency medical services times for suspected stroke in North Carolina

OBJECTIVE

Our objectives were to describe time intervals of EMS encounters for suspected stroke patients in North Carolina (NC) and evaluate differences in EMS time intervals by community socioeconomic status (SES) and rurality.

METHODS

This cross-sectional study used statewide data on EMS encounters of suspected stroke in NC in 2019. Eligible patients were adults requiring EMS transport to a hospital following a 9-1-1 call for stroke-like symptoms. Incident street addresses were geocoded to census tracts and linked to American Community Survey SES data and to rural-urban commuting area (RUCA) codes. Community SES was defined as high, medium, or low based on tertiles of an SES index. Urban, suburban, and rural tracts were defined by RUCA codes 1, 2-6, and 7-10, respectively. Multivariable quantile regression was used to estimate how the median and 90th percentile of EMS time intervals varied by community SES and rurality, adjusting for each other; patient age, gender, and race/ethnicity; and incident characteristics.

RESULTS

We identified 17,117 eligible EMS encounters of suspected stroke from 2028 census tracts. The population was 65% 65+ years old; 55% female; and 69% Non-Hispanic White. Median response, scene, and transport times were 8 (interquartile range, IQR 6-11) min, 16 (IQR 12-20) min, and 14 (IQR 9-22) minutes, respectively. In quantile regression adjusted for patient demographics, minimal differences were observed for median response and scene times by community SES and rurality. The largest median differences were observed for transport times in rural (6.7 min, 95% CI 5.8, 7.6) and suburban (4.7 min, 95% CI 4.2, 5.1) tracts compared to urban tracts. Adjusted rural-urban differences in 90th percentile transport times were substantially greater (16.0 min, 95% CI 14.5, 17.5). Low SES was modesty associated with shorter median (-3.3 min, 95% CI -3.8, -2.9) and 90th percentile (-3.0 min, 95% CI -4.0, -2.0) transport times compared to high SES tracts.

CONCLUSIONS

While community-level factors were not strongly associated with EMS response and scene times for stroke, transport times were significantly longer rural tracts and modestly shorter in low SES tracts, accounting for patient demographics. Further research is needed on the role of community socioeconomic deprivation and rurality in contributing to delays in prehospital stroke care.