Helicopter Emergency Medical Service System Research Articles

A national multi centre pre-hospital ECPR stepped wedge study; design and rationale of the ON-SCENE study

BackgroundThe likelihood of return of spontaneous circulation with conventional advanced life support is known to have an exponential decline and therefore neurological outcome after 20 min in patients with a cardiac arrest is poor. Initiation of venoarterial ExtraCorporeal Membrane Oxygenation (ECMO) during resuscitation might improve outcomes if used in time and in a selected patient category. However, previous studies have failed to significantly reduce the time from cardiac arrest to ECMO flow to less than 60 min. We hypothesize that the initiation of Extracorporeal Cardiopulmonary Resuscitation (ECPR) by a Helicopter Emergency Medical Services System (HEMS) will reduce the low flow time and improve outcomes in refractory Out of Hospital Cardiac Arrest (OHCA) patients.MethodsThe ON-SCENE study will use a non-randomised stepped wedge design to implement ECPR in patients with witnessed OHCA between the ages of 18–50 years old, with an initial presentation of shockable rhythm or pulseless electrical activity with a high suspicion of pulmonary embolism, lasting more than 20, but less than 45 min. Patients will be treated by the ambulance crew and HEMS with prehospital ECPR capabilities and will be compared with treatment by ambulance crew and HEMS without prehospital ECPR capabilities. The primary outcome measure will be survival at hospital discharge. The secondary outcome measure will be good neurological outcome defined as a cerebral performance categories scale score of 1 or 2 at 6 and 12 months.DiscussionThe ON-SCENE study focuses on initiating ECPR at the scene of OHCA using HEMS. The current in-hospital ECPR for OHCA obstacles encompassing low survival rates in refractory arrests, extended low-flow durations during transportation, and the critical time sensitivity of initiating ECPR, which could potentially be addressed through the implementation of the HEMS system. When successful, implementing on-scene ECPR could significantly enhance survival rates and minimize neurological impairment.Trial registrationClinicaltyrials.gov under NCT04620070, registration date 3 November 2020.

Severity-Driven Trends in Mortality in a Large Regionalized Critical Care Transport Service

ObjectiveThe epidemiology accompanying helicopter emergency medical services (HEMS) transport has evolved as agencies have matured and become integrated into regionalized health systems, as evidenced primarily by nationwide systems in Europe. System-level congruence between Europe and the United States, where HEMS is geographically fragmentary, is unclear. In this study, we provide a temporal, epidemiologic characterization of the largest standardized private, nonprofit HEMS system in the United States, STAT MedEvac. MethodsWe obtained comprehensive timing, procedure, and vital signs data from STAT MedEvac prehospital electronic patient care records for all adult patients transported to UPMC Health System hospitals in the period of January 2012 through October 2021. We linked these data with hospital electronic health records available through June 2018 to establish length of stay and vital status at discharge. ResultsWe studied 90,960 transports and matched 62.8% (n = 57,128) to the electronic health record. The average patient age was 58.6 years ( 19 years), and most were male (57.9%). The majority of cases were interfacility transports (77.6%), and the most common general medical category was nontrauma (72.7%). Sixty-one percent of all patients received a prehospital intervention. Overall, hospital mortality was 15%, and the average hospital length of stay (LOS) was 8.8 days ( 10.0 days). Observed trends over time included increases in nontrauma transports, level of severity, and in-hospital mortality. In multivariable models, case severity and medical category correlated with the outcomes of mortality and LOS. ConclusionIn the largest standardized nonprofit HEMS system in the United States, patient mortality and hospital LOS increased over time, whereas the proportion of trauma patients and scene runs decreased.

Determining a Need for Point-of-Care Ultrasound in Helicopter Emergency Medical Services Transport

ObjectivePoint-of care-ultrasound (PoCUS) is useful in evaluating unstable emergency department patients. The portability of this technology increases its potential use in prehospital settings, including helicopter emergency medical services (HEMS) programs. Identifying useful applications may support implementing a PoCUS program that develops sonography skills for prehospital providers. The aim of this study was to determine the HEMS patient population that would benefit from prehospital PoCUS for hypotension and how commonly the extended focused assessment with sonography in trauma (E-FAST) for trauma patients or the rapid ultrasound in shock (RUSH) for medical patients could be used by HEMS. MethodsA retrospective chart review was performed over a 1-year period of adult patients transported by a midwestern HEMS system. Charts were reviewed for episodes of hypotension. ResultsThe chart review included 216 charts, of which 3 were excluded. Of the 213 cases, 100 were trauma patients, and 113 were medical patients. Of the trauma patients, 51% experienced hypotension, as did 73 of 113 medical patients. ConclusionFifty percent of HEMS patients may benefit from PoCUS to evaluate for hypotension in flight.

Factors That Contribute to Provider Decision Between Direct and Video Laryngoscopy in a Helicopter Emergency Medical Services System: A Survey

ObjectiveIn caring for critically ill patients in the prehospital setting, rapid, definitive airway management is a high-risk, crucial procedure. All helicopter emergency medical services (HEMS) providers must proficiently and safely perform this procedure. Little information is available about the preference and efficacy of video laryngoscopy (VL) compared with direct laryngoscopy (DL). Additionally, there is a paucity of research investigating which method of intubation is more successful in the HEMS setting. The objective of this study was to delineate factors that contribute to provider decision regarding the method of orotracheal intubation and compare the frequency of use for each method. MethodsAn anonymous online survey was distributed to all providers in a single HEMS program. The survey results were deidentified and blinded to the researchers. ResultsThe survey was sent to 40 HEMS providers; 29 responded, and 119 total intubations were reported. Method familiarity and patient condition were the most commonly cited reasons for choosing both DL and VL for intubation. DL accounted for 15 intubation attempts, whereas 104 attempts were completed by VL. ConclusionFor both laryngoscopy techniques, the top reasons cited for selecting an intubation technique were being comfortable with that technique and patient presentation. Further investigation with chart review would help confirm the reported data.

Intubation during a medevac flight: safety and effect on total prehospital time in the helicopter emergency medical service system

IntroductionThe Helicopter Emergency Medical Service (HEMS) commonly intubates patients who require advanced airway support prior to takeoff. In-flight intubation (IFI) is avoided because it is considered difficult due to limited space, difficulty communicating, and vibration in flight. However, IFI may shorten the total prehospital time. We tested whether IFI can be performed safely by the HEMS.MethodsWe conducted a retrospective cohort study in adult patients transported from 2010 to 2017 who received prehospital, non-emergent intubation from a single HEMS. We divided the cohort in two groups, patients intubated during flight (flight group, FG) and patients intubated before takeoff (ground group, GG). The primary outcome was the proportion of successful intubations. Secondary outcomes included total prehospital time and the incidence of complications.ResultsWe analyzed 376 patients transported during the study period, 192 patients in the FG and 184 patients in the GG. The intubation success rate did not differ between the two groups (FG 189/192 [98.4%] vs. GG 179/184 [97.3%], p = 0.50). There were also no differences in hypoxia (FG 4/117 [3.4%] vs. GG 4/95 [4.2%], p = 1.00) or hypotension (FG 6/117 [5.1%] vs. GG 5/95 [5.3%], p = 1.00) between the two groups. Scene time and total prehospital time were shorter in the FG (scene time 7 min vs. 14 min, p < 0.001; total prehospital time 33.5 min vs. 40.0 min, p < 0.001).ConclusionsIFI was safely performed with high success rates, similar to intubation on the ground, without increasing the risk of hypoxia or hypotension. IFI by experienced providers shortened transportation time, which may improve patient outcomes.

On the use of economic evaluation of new technology in helicopter emergency medical services

When evaluating new technology in helicopter emergency medical services (HEMS), economic evaluation is normally part of the assessment. The outcome of economic evaluation may provide fruitful insight for the decision-makers, but, due to the complexity of the HEMS system, it is challenging to perform such evaluations in this context. A change in the components affects the whole system, and a lack of consideration of system components and their interactions may lead to unintended economic consequences when implementing new technology. Ultimately, this may cause a negative contribution to overall patient safety. We propose a conceptual methodology, using a systems model as part of the economic evaluation. The article is a revised and expanded version of a conference article presented at ESREL 2017, Slovenia.

Transport of ventilated emergency patients from the air rescue service to the hospital destination (HOVER study) : Results of an online survey

In Germany more than 110,000 helicopter emergency medical service (HEMS) missions are carried out annually. Aconsiderable number of patients are ventilated during the flight. So far, structured surveys with respect to the ground transport from the helipad to the hospital facility and handover of ventilated patients in the emergency room (ER) are not available in the German-speaking HEMS system. The handover of ventilated HEMS patients in the ER (HOVERI study) explored the use of the helicopter ventilator and medical equipment during the transport from the hospital landing site to the ER. After approval by the HEMS operators, emergency medical doctors and HEMS technical crew members (HEMS-TC) of 145 German-speaking HEMS bases were invited to participate in an anonymous online survey (period: 1 February 2018-1 March 2018). Each participant was only allowed to submit the survey once. Data of 569 participants were completely analyzed, with responses from 429 emergency physicians and 140 HEMS-TC (75% from Germany, 13% Switzerland, 11% Austria, 1% Italy and Luxembourg). The most frequent type of aircraft used was the Eurocopter (EC)/Airbus helicopter(H) 135 (60.5%) followed by the EC/H 145 (33%). The majority of the respondents (53%) principally used the helicopter ventilator machine for patient transport from the helipad to the ER, 38% used it depending on the circumstances and 7% never used it. Of the participants 52% always took the emergency backpack for patient transport to the ER, 43% depending on the situation and 5% never took it along. The availability of oxygen or aventilator at the helipad was considered to be helpful (59% and 45%, respectively), obligatory (25% and 14%, respectively) but was also considered unnecessary by some participants (16% and 40%, respectively). The collection of the HEMS team by ahospital team at the helipad was rated as helpful (64%) or mandatory (19%), 12% considered it to be unimportant and 5% even disturbing. For most respondents (58.5%) the responsibility for the patient ended after astructured handover on reaching the internal hospital target area (e.g. the ER). The management of the handover of ventilated emergency patients in German-speaking HEMS is heterogeneously structured. Only approximately 50% of the participants frequently carried the helicopter ventilator and emergency equipment during patient transport to the ER. Depending on the situation, more than 90% of the respondents used the helicopter ventilator and emergency backpack during the transport. The collection of the HEMS team by ahospital team at the helipad was appreciated by the majority of participants. The use of the helicopter ventilator for patient transport to the ER needs to be explored in future studies. The study was registered at the Research Registry ( www.researchregistry.com ) under the following number: researchregistry2925.

Increasing complexity of medical technology in helicopter emergency medical services and consequences for patient safety

There is a trend for helicopter emergency medical services (HEMS) to rapidly adopt technologic advances from specialised healthcare within hospitals, ignoring other parts of the HEMS system. Using economic theory, we show that, when making investments in new technology, lack of consideration of system factors does not necessarily improve practice. The introduction of new technology may unintentionally add to work system complexity and workload. This can make a negative contribution to patient safety and healthcare quality.

Video Laryngoscopic Techniques Associated with Intubation Success in a Helicopter Emergency Medical Service System

Objectives. Video laryngoscopy (VL) is a technical adjunct to facilitate endotracheal intubation (ETI). VL also provides objective data for training and quality improvement, allowing evaluation of the technique and airway conditions during ETI. Previous studies of factors associated with ETI success or failure are limited by insufficient nomenclature, individual recall bias and self-report. We tested whether the covariates in prehospital VL recorded data were associated with ETI success. We also measured association between time and clinical variables. Methods. Retrospective review was conducted in a non-physician staffed helicopter emergency medical service system. ETI was typically performed using sedation and neuromuscular-blockade under protocolized orders. We obtained process and outcome variables from digitally recorded VL data. Patient characteristics data were also obtained from the emergency medical service record and linked to the VL recorded data. The primary outcome was to identify VL covariates associated with successful ETI attempts. Results. Among 304 VL recorded ETI attempts in 268 patients, ETI succeeded for 244 attempts and failed for 60 attempts (first-pass success rate, 82% and overall success rate, 94%). Laryngoscope blade tip usually moved from a shallow position in the oropharynx to the vallecula. In the multivariable logistic regression analysis, attempt time (p = 0.02; odds ratio [OR] 0.99), Cormack-Lehane view (p < 0.001; OR 0.23), bodily fluids obstructing the view (p = 0.01; OR 0.29), and VL equipment failure (p < 0.001; OR 0.14) were negatively associated with successful attempts. Bodily fluids obstructing the view (p < 0.001; hazard ratio [HR] 0.51), VL equipment failure (p = 0.003; HR 0.42), shallow placement of blade tip within 4 seconds (p < 0.001; HR 0.40), number of forward movements (p < 0.001; HR 0.84), trauma (p = 0.04; HR 0.65), and neurological diagnosis (p = 0.04; HR 0.60) were associated with longer ETI attempt time. Conclusions. Bodily fluids obstructing the view, equipment problems, higher Cormack-Lehane view, and longer ETI attempt time were negatively associated with successful ETI attempts. Initially shallow blade tip position may associate with longer ETI time. VL is useful for measuring and describing multiple factors of ETI and can provide valuable data.

ACN(AACN)とドクターヘリ事業(&lt;特集&gt;進化し続ける自動車の安全性能)

ACN(AACN)とドクターヘリ事業(&lt;特集&gt;進化し続ける自動車の安全性能)

In-Flight Breech Delivery in Finnish Lapland

Although medical crews may initially approach obstetric transport requests with (at least internal) trepidation, it has been shown that the risk of an in-flight delivery occurring is extremely low, even among patients considered high risk.1–4 Nevertheless, the greatest concern of helicopter emergency medical service (HEMS) personnel remains the potential for in-flight delivery.5Finland is a Northern European country, with a land area almost equivalent to that of the US state of New Mexico. The Finnish HEMS system is managed by FinnHEMS, and there are 6 HEMS units in Finland. The northernmost HEMS unit, FinnHEMS 51, is based at Rovaniemi Airport in Finnish Lapland, which is located within the Arctic Circle; it operates over a remote and sparsely habited area. Finnish Lapland accounts for almost 30% of Finland by area; however, the density of population is low (only 2.0 persons per square kilometer), and the average annual year-round temperature is only —1°C (30°F).6 So far, there has been only 1 reported in-flight delivery; in 1939, a baby girl was born in an airplane operated by the Finnish Border Guard.7

Physician staffed helicopter emergency medical service dispatch via centralised control or directly by crew – case identification rates and effect on the Sydney paediatric trauma system

BackgroundSevere paediatric trauma patients benefit from direct transport to dedicated Paediatric Trauma Centres (PTC). Parallel case identification systems utilising paramedics from a centralised dispatch centre versus the crew of a physician staffed Helicopter Emergency Medical Service (HEMS) allowed comparison of the two systems for case identification rates and subsequent timeliness of direct transfer to a PTC.MethodsPaediatric trauma patients over a two year period from the Sydney region with an Injury Severity Score (ISS) > 15 were retrospectively identified from a state wide trauma registry. Overall paediatric trauma system performance was assessed by comparisons of the availability of the physician staffed HEMS for patient characteristics, transport mode (direct versus indirect) and the times required for the patient to arrive at the paediatric trauma centre. The proportion of patients transported directly to a PTC was compared between the times that the HEMS service was available versus the time that it was unavailable to determine if the HEMS system altered the rate of direct transport to a PTC. Analysis of variance was used to compare the identifying systems for various patient characteristics when the HEMS was available.ResultsNinety nine cases met the inclusion criteria, 44 when the HEMS system was operational. Patients identified for physician response by the HEMS system were significantly different to those that were not identified with higher median ISS (25 vs 18, p = 0.011), and shorter times to PTC (67 vs 261mins, p = 0.015) and length of intensive care unit stays (2 vs 0 days, p = 0.045). Of the 44 cases, 21 were not identified, 3 were identified by the paramedic system and 20 were identified by the HEMS system, (P < 0.001). Direct transport to a PTC was more likely to occur when the HEMS dispatch system was available (RR 1.81, 95% CI 1.20-2.73). The median time (minutes) to arrival at the PTC was shorter when HEMS available (HEMS available 92, IQR 50-261 versus HEMS unavailable 296, IQR 84-583, P < 0.01).ConclusionsPhysician staffed HEMS crew dispatch is significantly more likely to identify cases of severe paediatric trauma and is associated with a greater proportion of transports directly to a PTC and with faster times to arrival.

Role of resuscitative emergency field thoracotomy in the Japanese helicopter emergency medical service system

Objective We investigated whether emergency thoracotomy (ET) performed in pre-hospital settings contributed to saving the lives of blunt trauma patients with impending or recent cardiac arrest. Methods Eighty-one consecutive cardiac arrest patients with blunt trauma were performed ET before or after arrival at the emergency department (ED). These were reviewed retrospectively and were classified into the following three groups: (1) an emergency field thoracotomy was performed (EFT group, n = 34); (2) a doctor dispatched to the scene, but the thoracotomy was performed in the ED (EDT-a group, n = 10); and (3) no doctor dispatched to the scene, and the thoracotomy was performed in the ED (EDT-b group, n = 37). The patients in the EFT and EDT-a groups were managed within the Japanese helicopter emergency medical service system with a doctor dispatched to the scene. Result The time between the arrival of the EMT at the scene and the start of the thoracotomy was significantly shorter in the EFT group than in the EDT-b group (19.2 ± 7.9 min vs. 30.7 ± 6.8 min, p < 0.001). In the EFT group, the “ICU admission” rate was significantly higher among the patients who experienced cardiac arrest after the EMT arrival than among the patients who experienced cardiac arrest before the EMT arrival (70% vs. 8%, p = 0.001). Unfortunately, however, there were no survivors in this series. Conclusion These findings indicate that “early access” to a doctor's expertise and the performance of an “emergency field thoracotomy” might be two important factors for improving the possibility of saving the lives of blunt trauma patients with impending or recent cardiac arrest.

The Future of Emergency Medical Service System Based on Prehospital Emergency Medical Care

Prehospital emergency medical care (PEMC) refers to events in which a medical crew, including emergency physicians and nurses, is dispatched to a prehospital scene to provide treatment for patients. The Japanese HEMS (Helicopter Emergency Medical Service) system, also known Doctor-Helicopter, has enabled the establishment of a PEMC system. The Hokusoh HEMS has been dispatched on 587 missions, representing 15.6% of all Japanese HEMS dispatches to emergency sites in 2008. Among 151 trauma patients with an Injury Severity Score greater than 15, the Revised Trauma Score at the time of arrival at the emergency department was significantly higher than that before the prehospital treatment provided by HEMS (6.57±1.63 vs. 6.16±1.65; p<0.001). The coronary angiography time was also significantly shorter in the HEMS group than in the ground ambulance group (98.8±29.2 minutes vs. 126.6±48.7 minutes; p<0.05). These results show that the Japanese HEMS system can help improve the emergency medical system, as have similar helicopter services in the United States and Europe. However, a rapid response ground-based system is also needed to compensate for limitations of the HEMS, such those arising from weather and night-time conditions. Furthermore, the PEMC system requires an early alert and over-triage of the helicopter or ground ambulance dispatch (THESE TERMS ARE STILL UNCLEAR). The HEMS should also be available to transport Disaster Medical Assistance Teams to disaster sites, such as major accidents or earthquakes. Thus, the efficient deployment and networking of the HEMS are needed for the practical use of Doctor Helicopters in disaster situations. The education and training of young physicians dispatched to the scenes of accidents is also essential for establishing the PEMC system. Such physicians must not only be able to treat patients but must also have the discretion and talent to control the accident site and assume a leadership position. Such skills should be fostered through on-the-job training involving actual missions onboard a helicopter or a ground ambulance while accompanied by a senior physician, rather than through lectures or simulations. The PEMC represents proactive, not reactive, medical care and may offer a solution to the present insufficiencies in emergency health care. The Hokusoh HEMS wishes to propose a new model for emergency medical services through the use of a PEMC system incorporating both helicopter and ground-based ambulances.

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 andgender, mechanism of injury, initial vital signs, Revised Trauma Score (RTS), andthe 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 and345 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 and14 (47.0% vs. 49.3%), andgreater 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 andinterhospital 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. Key words: triage; injury severity score; emergency medical services; air ambulances; transportation of patients; helicopters.

Rapid response car as a supplement to the helicopter in a physician-based HEMS system.

The purpose of this study was to describe the use of a rapid response car (RRC) as a supplement to the ambulance helicopter in a mixed urban/rural region in Norway. Data from all the requested missions were collected from standard flight records. Operational factors, patient characteristics, primary diagnosis, treatment and modes of transport were registered and analyzed retrospectively. In 1999-2001, a total of 4777 requests were included in the study, resulting in the initiation of 3172 helicopter and 752 RRC missions. In the RRC missions, 224 patients received advanced medical treatment that would otherwise not have been provided. For 181 patients, the availability of the RRC was crucial for receiving the treatment of the helicopter emergency medical services (HEMS). The cost of equipping the base with the RRC increased the annual budget by less than one percent. The RRC was essential for solving missions in periods of non-flying conditions. The RRC increased the availability of the advanced prehospital life support offered by the HEMS in this region. Taking the modest increase in cost into consideration, it seems reasonable that this HEMS, covering mixed urban and rural areas, is equipped with such a vehicle.

Prehospital ECG transmission: comparison of advanced mobile phone and facsimile devices in an urban Emergency Medical Service System

Objective: To compare the speed and reliability of electrocardiogram (ECG) transmissions from the prehospital setting to a conventional table facsimile device and to an advanced mobile phone in a Helicopter Emergency Medical Service System (HEMS). Methods: Eighteen authentic ECGs stored in the memory module of a monitor defibrillator were used. The ECGs were (1) sent directly from the monitor defibrillator to a table fax and an advanced mobile phone at the HEMS base; (2) printed out and sent from a mobile fax connected to an ordinary mobile phone to the table fax and the advanced mobile phone at the HEMS base; (3) printed out and sent from an ordinary table fax as well as from a table fax connected to a satellite phone system to the receiving devices at the HEMS base. Results: When the ECGs were sent from the table fax via satellite, the transmission times were longer to the advanced mobile phone than to the table fax at the HEMS base (1 min 54 s±0 min 21 s vs. 1 min 37 s±0 min 20 s, (mean±SD), ( P<0.01). Regarding transmission from the other fax devices, there were no differences in transmission times between the two receiving devices. The fastest way to transmit ECGs to the advanced mobile phone was to send it from conventional table fax (1 min 22 s±0 min 18 s) and the longest transmission times were with mobile fax connected to mobile phone (5 min 23 s±3 min 5 s). In all ECGs transmitted except one the cardiac rhythm and ST-changes could be recognised. Conclusion: An advanced mobile phone is as fast and reliable as a conventional table fax in receiving ECGs. A mobile phone with advanced features is a practical tool for HEMS physicians who need to evaluate ECGs in the prehospital setting.