MEDEVAC: Une réanimation avancée rapporte

A review of the first 10 years of critical care aeromedical transport during operation iraqi freedom and operation enduring freedom: the importance of evacuation timing

Ingals N et Al. JAMA Surg. 2014 Aug;149(8):807-13

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Ce document est très intéressant car il met en avant l'intérêt du transport des blessés de guerre par des équipes maîtrisant toutes les facettes du damage control resusictation tant au niveau médical que paramédical. Une approche très similaire est celle des MERT-E

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Advances in the care of the injured patient are perhaps the only benefit of military conflict. One of the unique aspects of the military medical care system that emerged during Operation Iraqi Freedom and Operation Enduring Freedom has been the opportunity to apply existing civilian trauma system standards to the provision of combat casualty care across an evolving theater ofoperations.

OBJECTIVES:

To identify differences in mortality for soldiers undergoing early and rapid evacuation from the combat theater and to evaluate the capabilities of the Critical Care Air Transport Team (CCATT) and Joint Theater Trauma Registry databases to provide adequate data to support future initiatives for improvement of performance.

DESIGN, SETTING, AND PARTICIPANTS:

Retrospective review of CCATT records and the Joint Theater Trauma Registry from September 11, 2001, to December 31, 2010, for the in-theater military medicine health system, including centers in Iraq, Afghanistan, and Germany. Of 2899 CCATT transport records, those for 975 individuals had all the required data elements.

EXPOSURE:

Rapid evacuation by the CCATT.

MAIN OUTCOMES AND MEASURES:

Survival as a function of time from injury to arrival at the role IV facility at Landstuhl Regional Medical Center.

RESULTS:

The patient cohort demonstrated a mean Injury Severity Score of 23.7 and an overall 30-day mortality of 2.1%. Mortality en route was less than 0.02%. Statistically significant differences between survivors and decedents with respect to the Injury Severity Score (mean [SD], 23.4 [12.4] vs 37.7 [16.5]; P < .001), cumulative volume of blood transfused among the patients in each group who received a transfusion (P < .001), worst base deficit (mean [SD], -3.4 [5.0] vs -7.8 [6.9]; P = .02), and worst international normalized ratio (median [interquartile range], 1.2 [1.0-1.4] vs 1.4 [1.1-2.2]; P = .03) were observed. We found no statistically significant difference between survivors and decedents with respect to time from injury to arrival at definitive care.

CONCLUSIONS AND RELEVANCE:

Rapid movement of critically injured casualties within hours of wounding appears to be effective, with a minimal mortality incurred during movement and overall 30-day mortality. We found no association between the duration of time from wounding to arrival at Landstuhl Regional Medical Center with respect to mortality.

Transfusion en vol: Sécurité assurée

Risk Management Analysis of Air Ambulance Blood Product Administration in Combat Operations

Powell-Dunford Net Al. Aviat Space Environ Med. 2014 Nov;85(11):1130-5

 

BACKGROUND:

Between June-October 2012, 61 flight-medic-directed transfusions took place aboard U.S. Army Medical Evacuation (medevac) helicopters in Afghanistan. This represents the initial experience for pre-hospital blood product transfusion by U.S. Army flight medics.

METHODS:

We performed a retrospective review of clinical records, operating guidelines, after-action reviews, decision and information briefs, bimonthly medical conferences, and medevac-related medical records.

RESULTS:

A successful program was administered at 10 locations across Afghanistan. Adherence to protocol transfusion indications was 97%. There were 61 casualties who were transfused without any known instance of adverse reaction or local blood product wastage. Shock index (heart rate/systolic blood pressure) improved significantly en route, with a median shock index of 1.6 (IQR 1.2-2.0) pre-transfusion and 1.1 (IQR 1.0-1.5) post-transfusion (P < 0.0001). Blood resupply, training, and clinical procedures were standardized across each of the 10 areas of medevacoperations.

DISCUSSION:

Potential risks of medical complications, reverse propaganda, adherence to protocol, and diversion and/or wastage of limited resources were important considerations in the development of the pilot program. Aviation-specific risk mitigation strategies were important to ensure mission success in terms of wastage prevention, standardized operations at multiple locations, and prevention of adverse clinical outcomes. Consideration of aviation risk mitigation strategies may help enable other helicopter emergency medical systems to develop remote pre-hospital transfusion capability. This pilot program provides preliminary evidence that blood product administration by medevac is safe.

MEDEVAC hélico: + compliqué qu'on le croit

Interhospital Patient Transport by Rotary Wing Aircraft in a Combat Environment: Risks, Adverse Events, and Process Improvement

Lehmann R et Al. J Trauma. 2009 Apr;66(4 Suppl):S31-4

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Le transport secondaire de blessés de guerre peut s'envisager entre deux structures hospitalières ou bien à partir un role 1 distant vers un role 2/3. Le document présenté exprime que malgré un haut degré de préparation, un certain nombre de difficultés risque d'apparaître en vol. Ceci impose de professionaliser à un haut standard les équipes de convoyage (1) et tout particulièrement celles de longue durée.

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Background: Helicopter transport of injured or ill patients in Operation Iraqi Freedom is a necessary but often high-risk endeavor. Our facility initiated a thorough process improvement and standardization initiative after several adverse outcomes. This report describes the results after this initiative, and evaluates the applicability of a civilian transport risk assessment tool to the combat environment.

Methods: Review of all preflight, in-flight, and postflight records for helicopter medevac missions over a 7-month period. Adverse events included major equipment failures, clinical deterioration, or the need for urgent interventions on arrival. Transport risk scores (TRS) were calculated and assessed for correlation with adverse events.

Results: There were 149 patient transports identified, 95 (64%) for trauma (mean Injury Severity Score, 21) and 54 (36%) for medical illness. Major surgical intervention before the flight was required in 66 (44%), massive transfusion in 29 (20%), and the majority were transported within 8 hours of surgery. In-flight mechanical ventilation was required in 53%, and 20% required vasopressors or cardioactive medications. Adverse events included equipment failures in 17% of flights, in-flight clinical deterioration in 30%, and 9% required an urgent intervention on arrival. However, there were no deaths or significant flight-related morbidities identified. The mean TRS was significantly higher in patients with adverse events (9.1) versus those without (7.4, p < 0.05), but it showed only moderate discriminative ability (area under curve
0.65, p < 0.01).

"Documented adverse events included equipment failures in 17% of flights, in-flight clinical deterioration in 30%, and 9% required an urgent intervention on arrival. In-flight deteriorations included hypotension in 10%, oxygen desaturation in 7%, arrhythmia in 6%, and tachycardia or bradycardia (rate,
120 or 60 beats per minute) in 32%."

Conclusions: Helicopter transport in a combat environment carries significant risk of adverse events because of the patient characteristics and inherent limitations of the transport platform. Strict attention to standardization, training, and process improvement is necessary to achieve optimal outcomes. The civilian TRS had lower discriminative ability in this military setting.

Conditionner un blessé grave

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Un nouveau concept de triage ?

Medical evacuation and triage of combat casualties in Helmand Province, Afghanistan: October 2010-April 2011

Clarke JE et Al. Mil Med. 2012 Nov;177(11):1261-6

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Un article de synthèse sur l'organisation de la chaîne de prise en charge des blessés par nos confrères anglais, avec notamment l'emploi d'une évolution majeure pour le un système anglo-saxon (lire ce document): le recours à des EVASAN médicalisées par des personnels ayant une pratique régulière de la prise en charge de patients en état critique. Cet article est intéressant car il insiste sur l'importance du triage et le rôe prééminent que peuvent jouer les role 2 notamment si les élongations sont importantes.

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Medical evacuation of combat casualties in Operation Enduring Freedom-Afghanistan is achieved primarily by helicopter, because of distances involved as well as ground-based threats. In Helmand Province, evacuation from the point of injury may occur on a variety of helicopter evacuation platforms with disparate levels of attendant medical expertise. Furthermore, triage to a medical treatment facility may involve varying echelons of care before definitive management. Consequently, considerable differences in medical care may be encountered between point of injury and definitive treatment. We discuss the role of helicopter-based medical evacuation in Helmand, Afghanistan, as well as triage and timelines to the most appropriate medical facilities. Based on our experience and available evidence, we have made recommendations to regional commanders which favor the utilization of prehospital critical care teams aboard helicopter-based evacuation platforms and direct triage to the highest echelon of care available when feasible

Médecin EXPERIMENTÉ: Pronostic amélioré

Determining the composition and benefit of the pre-hospital medical response team in the conflict setting

Davis PR et Al. J R Army Med Corps. 2007 Dec;153(4):269-73

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La composition des équipes d'evasan tactique fait débat. La présence d'un médecin serait associée à une meilleure survie des blessés les plus graves, surtout si les délais de prise en charge par une équipe chirurgicales sont longs. Encore faut il que ce médecin ait de réelles compétences en matière de traumatologie et d'exercice de la médecine préhospitalière en situation isolée.

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Aim: To determine the optimal composition of the pre-hospital medical response team (MERT) and the value of prehospitalvcritical care interventions in a military setting, and specifically to determine both the benefit of including a doctor in the pre-hospital response team and the relevance of the time and distance to definitive care.

Method: A comprehensive review of the literature incorporating a range of electronic search engines and hand searches of key journals.

Results: There was no level 1 evidence on which to base conclusions. The 15 most relevant articles were analysed in detail. There was one randomized controlled trial (level 2 evidence) that supports the inclusion of a doctor on MERT. Several cohort studies were identified that analysed the benefits of specific critical care interventions in the pre-hospital setting.

Conclusions: A doctor with critical care skills deployed on the MERT is associated with improved survival in victims of major trauma. Specific critical care interventions including emergency endotracheal intubation and ventilation, and intercostal drainage are associated with improved survival and functional recovery in certain patients.

Doctors on board, utile ?

Doctor on board? What is the optimal skill-mix in military pre-hospital care?

Calderbank P et Al. Emerg Med J. 2011 Oct;28(10):882-3

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Le recul des MERT-E anglaise dans un contexte bien particulier  où le temps de vol moyen est de 3/4 d'heure. La présence d'un médecin n'est pas déterminante. Ce n'est pas du tout la même chose si les temps de vol sont longs (1).  

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BACKGROUNDS:  In a military setting, pre-hospital times may be extended due to geographical or operational issues. Helicopter casevac enables patients to be transported expediently across all terrains. The skill-mix of the pre-hospital team can vary.

AIM: To quantify the doctors' contribution to the Medical Emergency Response Team-Enhanced (MERT-E).

METHODS: A prospective log of missions recorded urgency category, patient nationality, mechanism of injury, medical interventions and whether, in the crew's opinion, the presence of the doctor made a positive contribution.

RESULTS: Between July and November 2008, MERT-E flew 324 missions for 429 patients. 56% of patients carried were local nationals, 35% were UK forces. 22% of patients were T1, 52% were T2, 21.5% were T3 and 4% were dead. 48% patients had blast injuries, 25% had gunshot wounds, 6 patients had been exposed to blast and gunshot wounds. Median time from take-off to ED arrival was 44 min. A doctor flew on 88% of missions. It was thought that a doctor's presence was not clinically beneficial in 77% of missions. There were 62 recorded physician's

INTERVENTIONS: The most common intervention was rapid sequence induction (45%); other interventions included provision of analgesia, sedation or blood products (34%), chest drain or thoracostomy (5%), and pronouncing life extinct (6%).

CONCLUSION: MERT-E is a high value asset which makes an important contribution to patient care. A relatively small proportion of missions require interventions beyond the capability of well-trained military paramedics; the indirect benefits of a physician are more difficult to quantify.

Medevac tactique:Médicalisation utile pour 30% des blessés

En-Route Care Capability From Point of Injury Impacts Mortality After Severe Wartime Injury

Morrison JJ et AL. Ann Surg 2013;257: 330–334

 

Il est difficile de se faire une idée de l'efficience de nos organisations de relève des blessés de guerre. En effet les 2/3 de ses derniers sont peu graves et ne nécessitent pas de pratiques avancées. Le conflit afghan a permis de confirmer la pertinence d'un certain nombre de faits: Une stratégie de conditionnement basé sur l'analyse des causes évitables de décès, l'importance de la mise en place d'un réseau structuré de prise en charge préhospitalière et hospitalière. Ce document confirme que la médicalisation avancée améliore la probabilité de survie des  blessés de gravité intermédiaire qui représentent tout de même près du  1/3 des cas rencontrés et qui justifient nos organisations. Ceci confirme que la maîtrise de pratiques de base de réanimation préhospitalière devrait donc être l'un des piliers de l'organisation des évacuations médicales tactiques. 

 

OBJECTIVE:

The objective of this study is to characterize modern point-of-injury (POI) en-route care platforms and to compare mortality among casualties evacuated with conventional military retrieval (CMR) methods to those evacuated with an advanced medical retrieval (AMR) capability.

BACKGROUND:

Following a decade of war in Afghanistan, the impact of en-route care capabilities from the POI on mortality is unknown.

METHODS:

Casualties evacuated from POI to one level III facility in Afghanistan (July 2008-March 2012) were identified from UK and US trauma registries. Groups comprised those evacuated by a medically qualified provider-led, AMR and those by a medic-led CMR capability. Outcomes were compared per incremental Injury Severity Score (ISS) bins.

RESULTS:

Most casualties (n = 1054; 61.2%) were in the low-ISS (1-15) bracket in which there was no difference in en-route care time or mortality between AMR and CMR. Casualties in the mid-ISS bracket (16-50) (n = 583; 33.4%) experienced the same median en-route care time (minutes) on AMR and CMR platforms [78 (58) vs 75 (93); P = 0.542] although those on AMR had shorter time to operation [110 (95) vs 117 (126); P < 0.001]. In this mid-ISS bracket, mortality was lower in the AMR than in the CMR group (12.2% vs 18.2%; P = 0.035). In the high-ISS category (51-75) (n = 75; 4.6%), time to operation was lower in the AMR than the CMR group (66 ± 77 vs 113 ± 122; P = 0.013) but there was no difference in mortality.

CONCLUSIONS:

This study characterizes en-route care capabilities from POI in modern combat. Conventional platforms are effective in most casualties with low injury severity. However, a definable injury severity exists for which evacuation with an AMR capability is associated with improved survival.

EVASAN: Médicalisé, c'est mieux

Performance improvement evaluation of forward aeromedical evacuation platforms in Operation Enduring Freedom

Apodaca A et All., J Trauma Acute Care Surg. 2013;75: S157YS

BACKGROUND: The following three helicopter-based medical evacuation platforms operate in Southern Afghanistan: the US Army emergency medical technician (basic)Yled DUSTOFF, US Air Force paramedic-led PEDRO, and UK physician-led medical emergency response team (MERT). Nearly 90% of battlefield deaths occur in the prehospital phase, comparative outcomes for these en route care platforms are unknown. The objective of this investigation was to characterize the nature of injuries in patients transported by three evacuation platforms. In addition, it aimed to compare observed versus predicted mortality among these provider groups.

METHODS: A performance improvement study involving 975 coalition patients injured in Southern Afghanistan, transported from the point of injury to a military hospital, was performed. All patients were alive on admission with prehospital documentation recorded in the US Department of Defense Trauma Registry from June 2009 to June 2011. The main outcome measure was in-hospital mortality and observed versus predicted (Trauma and Injury Severity Score [TRISS]) survival were the primary end points.

RESULTS: MERT transported more amputation and polytrauma casualties and included patients with higher mean Injury Severity Score (ISS) compared with PEDRO and DUSTOFF (16 [13] vs. 11 [10] and 10 [10] respectively; p G 0.001). DUSTOFF was excluded from the subgroup analysis owing to insufficient numbers of severely injured casualties with only one death. The overall mortality for MERT and PEDRO was similar (4.2% vs. 4.6%, p= 0.967). Stratifying by ISS, there was lower mortality in MERT compared with PEDRO in the range of 20 to 29 (4.8% vs. 16.2%, p = 0.021). The observed mortality among PEDRO casualties was as predicted with the exception of the range of 20 to 29, while mortality in MERTwas lower than predicted for all ISS groups with greater than 10.

 

CONCLUSION: MERT achieves greater than predicted survival, which may be related to the additional capabilities onboard. This supports the adoption of a versatile medical evacuation system with scalable crew and equipment configurations that adapt to meet the medical, tactical, and operational needs of future conflicts.

Mieux on est formé, plus on fait

Army flight medic performance of paramedic level procedures: Indicated vs performed

Bier SA et all. - J Emerg Med. 2013 May;44(5):962-9.

Of 984 interventions found to be indicated on the 406 charts that met inclusion criteria, 36% were rated as EMT-P level. Seventeen percent were indicated but not performed. EMT-Bs failed to perform indicated procedures 35% of the time vs. 3% in the EMT-P group (p < 0.001). For paramedic-level procedures, EMTBs failed to make 76% of appropriate interventions, compared to <1% in the EMT-P group (p < 0.001). Conclusions: There seems to be a substantial number of procedures beyond the scope of standard Army flight medic training being required for Army AMT missions. It seems that when advance interventions are indicated, those trained to the EMT-P level perform them significantly more often than those trained to Army standard. Conclusions: Based on the findings of this study, the authors suggest the Army consider adopting the standards required for civilian AMT

Commentaire:Notez la part de pédiatrie

Commentaire: EMT-B = Auxilaire sanitaire. EMT P = Technicien de niveau plutôt infirmiers formés exclusivement à la gestion de soins critiques. Pas d'équivalence avec la vision française (entre infirmier anesthésiste/réa ?)

Ceci milite pour la présence dans les vecteurs d'EVASAN notamment aériens de personnels paramédicaux spécifiques habitués à la mise en oeuvre de standards de soins critiques

MERT, PEDRO ou Dustoff ?

Pas simple de choisir les modalités d'intervention en zone de combat. Dans le document présenté une comparaison des moyens US et UK. Nous sommes entre la MERT-E UK et le PEDRO US ?

Medevac-Report-V1.2.pdf

Evasan hélico: Bien mieux avec du personnel compétent !

Impact of critical careYtrained flight paramedics on casualty survival during helicopter evacuation in the current war in Afghanistan
Mabry RL et all. J Trauma Acute Care Surg. 2012;73: S32YS37

On présente toujours les évacuations aériennes par hélicoptères conduites par les US comme très peu médicalisées du fait des compétences très limitées des combat medics habituellement embarqués.

Il faut réviser cette opinion, car outre le fait que le combat medic US peut être un vrai professionnel de l'urgence ( dès lors qu'il est EMT-P voire I, encore plus si il appartient à une unité comme le 75ème ranger ou les seals). C'est aussi le cas des médicalisations conduites par les unités qui dépendent de la garde nationale. Cette dernière semble en effet appliquer des standards civils armant ses hélicoptères d'au moins deux personnels flight medic dont l'un de niveau EMT-P, formés spécifiquement  et disposant d'une expérience professionnelle en médecine d'urgence de plus de 9 ans, et son binome de formation plus basique.

Une telle manière de procéder permet de réduire la mortalité à 48h des blessés transportés qui passe de 15% pour les blessés transportés par l'army à 8% pour les blessés transportés dans les hélicoptères de la garde nationale.

On voit là finalement l'esquisse d'une convergence enre nos modalités de transport de blessés, celles des anglais qui mettent en oeuvre les MERT-Enhanced et la garde nationale US.

Une exigence: Des professionnels expérimentés de l'urgence doivent être dans les vecteurs d'EVASAN, ce d'autant que les délais de transport sont longs supérieurs à 30 min.