key: cord-0870421-2g2ictd1 authors: Turc, Jean; Dupre, Henri-Louis; Beaussac, Madeleine; Murris, Sophie; Koch, Lionel; Paris, Raphael; Filippo, Julia Di; Distinguin, Berangère; Muller, Violaine; Boutonnet, Mathieu title: Collective aeromedical transport of COVID-19 critically ill patients in Europe: a retrospective study date: 2020-11-21 journal: Anaesth Crit Care Pain Med DOI: 10.1016/j.accpm.2020.11.004 sha: 647465fc50c08b3e2c16f0d22157ef06c52e4287 doc_id: 870421 cord_uid: 2g2ictd1 Background: In early 2020, the coronavirus disease 2019 (COVID-19) pandemic outbreak has posed the risk of critical care resources overload in every affected country. Collective interhospital transport of critically ill COVID-19 patients as a way to mitigate the localised pressure from overloaded intensive care units at a national or international level has not been reported yet. The aim of this study was to provide descriptive data about the first six collective aeromedical evacuation (MEDEVAC) of COVID-19 patients performed within Europe. Methods: This retrospective study included all adult patients transported by the first six collective MEDEVAC missions for COVID-19 patients performed within Europe on the 18th, 21st, 24th, 27th, 31st of March and the 3rd of April 2020. Results: Thirty-six patients with acute respiratory distress syndrome (ARDS) were transported aboard six MEDEVAC missions. The median duration of mechanical ventilation in ICU before transportation was 4 days (3-5.25). The median PaO2/FiO2 ratio obtained before, during the flight and at Day 1 after the transport was 180 mmHg (156-202,5), 143 mmHg (118,75-184,75) and 174 mmHg (129,5-205,5), respectively, with no significant difference. The median norepinephrine infusion rate observed before, during the flight and at Day 1 after the transport was 0,08 µg/kg-1.min-1 (0,00-0,20), 0,08 (0,00-0,25), and 0,07 (0,03-0,18), respectively, with no significant difference. No life-threatening event was reported. Conclusion: Collective aero-MEDEVAC of COVID-19 critically ill patients could provide a reliable solution to help control the burden of the disease at a national or international level. In early 2020, the coronavirus disease 2019 (COVID- 19) pandemic outbreak has posed the risk of critical care resources overload in every affected country. Collective interhospital transport of critically ill COVID-19 patients as a way to mitigate the localised pressure from overloaded intensive care units at a national or international level has not been reported yet. The aim of this study was to provide descriptive data about the first six collective aeromedical evacuation (MEDEVAC) of COVID-19 patients performed within Europe. This retrospective study included all adult patients transported by the first six collective MEDEVAC missions for COVID-19 patients performed within Europe on the 18 th , 21 st , 24 th , 27 th , 31 st of March and the 3 rd of April 2020. Thirty-six patients with acute respiratory distress syndrome (ARDS) were transported aboard six MEDEVAC missions. The median duration of mechanical ventilation in ICU before transportation was 4 days (3-5.25 ). The median PaO2/FiO2 ratio obtained before, during the flight and at Day 1 after the transport was 180 mmHg (156-202,5), 143 mmHg (118, 75) and 174 mmHg (129, 5) , respectively, with no significant difference. The median norepinephrine infusion rate observed before, during the flight and at Day 1 after the transport was 0,08 µg/kg -1 .min -1 (0,00-0,20), 0,08 (0,00-0,25), and 0,07 (0,03-0,18), respectively, with no significant difference. No life-threatening event was reported. Collective aero-MEDEVAC of COVID-19 critically ill patients could provide a reliable solution to help control the burden of the disease at a national or international level. Caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the coronavirus disease 2019 (COVID-19) outbreak became established in France, as in much of mainland Europe, in early March 2020 [1] . As in other countries, the distribution of the disease among the territories was heterogeneous and most cases were initially located in the Grand Est French region where a sudden rise of intensive care unit admissions was observed [1]. A specific risk during the pandemic was the risk of saturation of some local facilities, especially regarding critical care facilities. Hence, the French Government made the decision to transport ICU patients with SARS-CoV-2 from the Grand Est region to other areas with ICU availability. The French Air Force and the French Military Health Service were engaged to organise and deploy their collective airborne medical evacuation (MEDEVAC) service, an Airbus A330 Multi-Role Tanker Transport plane equipped with the MoRPHEE (Module de Réanimation pour Patient à Haute Elongation d'Evacuation) system, which transforms the plane into an ICU for the long-distance transport of critically ill patients [2] . Aboard six flights, the French Ministry of the Armed Forces has carried out the medical transportation of 36 critically ill patients from hospitals in the north east of France. During the same period, more than 600 patients have been transported by road, train or helicopter in France. Medical transportation of critically ill has been considered in case of pandemics or disaster but to date, no pandemic had imposed to resort to this mean. [3] . Moreover, interhospital transport of critically ill patients is a known high-risk period [4, 5] . The transport of mechanically ventilated patients suffering from acute respiratory distress syndrome (ARDS) has been regularly reported, however always on an individual basis [6, 7, 8] . Little is known about the specific challenges and risks of the transport of multiple victims with ARDS, especially in a pandemic context. The aim of this study was to provide descriptive data about the first six MEDEVAC missions of SARS-CoV-2 patients that were performed within Europe. This retrospective cohort study included all of the adult patients transported by the first six The transported patients were selected the day before the flight in coordination with their ICU doctors and regional health agencies. Among the patients requiring invasive mechanical ventilation, several simple criteria were used to select those who would be most suitable for transport: confirmed SARS-CoV-2 pneumonia, body-weight < 120 kg, PaO2/FiO2 ratio >120 mmHg, no ongoing prone position ventilation, and moderate infusion rates of catecholamine (norepinephrine infusion rate < 0.5 g.kg -1 .min -1 ) Exclusion criteria were: age < 18 years, incapability, consent withdrawal after written information was provided to the patient or relatives. Collective, strategic MoRPHEE MEDEVACs were originally conceived by the French Air Force and the French Military Health Service to repatriate severely injured war casualties. The MoRPHEE system provides a "flying ICU" facility that also complies with international aviation security regulations [9] . The system is based on mission-tailored 'plug-and-play' modules that can be installed into non-dedicated aircraft, in this case, an Airbus A330, to allow the repatriation of up to six critically ill patients at a time over long distances. Onboard facilities included mechanical ventilation with the transport ventilator LTV 1200 (CareFusion, Yorba Linda, CA), continuous monitoring (Welch Allyn Propaq CS), drug infusion, echography (M-Turbo; Sonosite, Bothell, WA), and delocalised biology [2] . The intensive care modules were set as illustrated in Figure 1 . The medical crew, specifically trained to perform MEDEVACs, was composed of three ICU physicians, two flight surgeons, three anaesthetist nurses, three flight nurses, and two critical care nurses [9] . Due to the high risk of contagion posed by the COVID-19 disease, the teams were reinforced by four experts in the management of biological risk from two specialised units of the French Military Health Service, and the French Air Force. The specific management of the biological risk associated with COVID-19 during flights will be discussed in another publication. Due to regulatory reasons, a three days interval was imposed between the MEDEVACs. The patients' current healthcare teams were encouraged to maintain any ongoing sedation, to induce muscle relaxation with long acting muscle relaxant, and to use closed-suction J o u r n a l P r e -p r o o f devices in order to limit the risk of tracheal tube disconnection and cabin contamination. A protective ventilation strategy using a low tidal volume and high positive end-expiratory pressure (PEEP) was established in order to prevent alveolar collapse, hypoxemia, and to minimise the risk of ventilator-induced lung injury. Data were extracted from the medical records using a standardised data collection form and from the missions' detailed reportings. Demographics, chronic disease states, biologics and norepinephrine requirements were obtained during the doc-to-doc call the day before the transport. Onboard ventilator settings, acute physiologic data and arterial blood gas analysis were recorded after a stabilisation period of 10 minutes after the take-off. Follow-up was done in collaboration with receiving units. The Charlson comorbidity index [10] and the Sequential Organ Failure Assessment (SOFA) score [11] were calculated for each patient before transportation. ARDS was defined and graded according to the Berlin definition [12] . Predicted body weight (PBW) was calculated according to the ARDS Network predicted body weight calculator [13] . The Richmond Agitation-Sedation scale was used to assess each patient [14] . In order to estimate potential adverse effects of the transport, we recorded and compared the PaO2/FiO2 ratio as well as norepinephrine requirement before, during and the day after the transport. Onboard events requiring medical intervention were identified from continuous monitoring and medical records. Life-threatening events (e.g., cardiac arrest, refractory hypoxemia or hypotension, accidental extubation) were also recorded. Descriptive statistics were provided. Continuous and categorical variables were respectively presented as median (1 st -3 rd quartiles) and n (%). Given the small sample size, the PaO2/FiO2 ratio and norepinephrine infusion rates before, during and the day after the transport were compared with a non-parametric test (Friedman test) performed with GraphPad Prism 7 (GraphPad Software, USA). (58-72), and the age range was from 49 to 78 years. The male-to-female sex ratio was 2. The three most frequent comorbidities were hypertension (n = 18 (50%)), obesity (n = 17 (47%)) and diabetes (n = 13 (36%)) and the median Charlson comorbidity index was 1 (0-1,25). Baseline characteristics of all patients are shown in Table 1 as well as organ failures recorded before transportation and onboard ventilatory settings. All patients were placed in a semirecumbent position and received a neuromuscular blockade and protective ventilation. Tidal volume was 6.5 mL.kg -1 (PBW) (6.2-7.0) and PEEP was 13 cmH20 (12) (13) (14) . Arterial blood gas analysis data were obtained from arterial lines in 29 patients. The We have here reported the transport of 36 COVID-19 ARDS patients during 6 collective aero MEDEVAC operations. All the patients could be transported from overloaded ICUs in the Grand Est region to 9 other hospitals in France and Germany where the ICU availability was greater. To our knowledge, this is the first experience of collective aero-MEDEVAC of patients with ARDS. Our study has outlined the selection criteria that we used to select patients transport and their management onboard. We do not report any life-threatening event or significant respiratory or haemodynamic aggravation during flight. Comorbidities as assessed by Charlson comorbidities index, obesity, or diabetes were frequent in our population, which is consistent with other work on COVID-19 ARDS [15] or ICU [16] patients. Also in agreement with previous other published data in COVID-19 patients, half of our patients were aged over 64 years, and a majority of our study population was male [15, 16, 17, 18] . On the other hand, it is also important to note that the patients were carefully selected for MEDEVAC, based on pre-established criteria. As a consequence, all of them presented with ARDS and were under invasive mechanical ventilation when they boarded the flight, but no one suffered from severe ARDS or required high-dose of norepinephrine. Transportations between medical facilities are well-known periods of risk [4, 5] . Of note, we did not identify an aggravation of the PaO2/FiO2 ratio or an increase of the norepinephrine requirements throughout the follow-up of patients. These data have been monitored by other authors during interhospital transport of ARDS critically ill patients [19] . They appear as a good approach to assess the potential adverse effects of interhospital transport, even if they cannot provide certain information on long-term outcomes of these patients. Before these flights, the MEDEVAC crew had both received training about and had experience with strategies to minimise the occurrence of adverse events, such as checklists. Despite this, most patients still presented with an event that required medical intervention during the Page 8 of 12 J o u r n a l P r e -p r o o f flight. All were promptly managed and none was life threatening. The frequency of events was higher than previously reported [7, 19] . Some authors observed similar rate of events during intrahospital transport of critically ill patients [20] . Overall, the proportion of respiratory events was lower than expected, whereas we faced many cardiovascular events, mainly related to the changeover of norepinephrine infusion pumps. A standardisation of the infusion set-up with no more than three infusion pumps might have helped limiting these events, but in the very complicated situation that our colleagues were facing in the Grand Est region, we chose not to surimpose external constraints. The relative ease of patient management and the stability of clinical symptoms during the MEDEVAC, however, strongly support the feasibility and practical implementation of such evacuations, both in France and elsewhere. In summary, although no intervention of this scale can be without risk, we do believe that the in-flight events that our patients encountered did not outweigh the benefits of the evacuation, which should be assessed both at an individual and collective point of view. Our study has some limitations. First, it was a retrospective study and thus vulnerable to the inherent limitations of such study design, especially the risk of bias due to the small patient population and small dataset. Secondly, patients were selected before the transportation and our results may not be reproducible with other selection criteria. Third, we chose to design the study in order to describe the patient management during the flight and we limited the follow-up of subsequent outcomes at Day 1 after the transport. The data collection of subsequent aspects is still in progress, and the report will be of great interest, but we chose to rapidly share our experience with colleagues. Fourth, these results are not directly replicable and require a specific training program of the MEDEVAC team. Finally, the heterogeneous distribution of both the disease and the strain on ICU facilities was patent in France but this may not be reproducible in other countries or continents. However, the strain of the disease on critical care resources reveals to be critical all over the world. This is the first report about collective MEDEVAC of patients with ARDS in an epidemic context. We hope that this information will be useful to those colleagues around the world who need to organise similar evacuations as the COVID-19 pandemic progresses, especially as we encountered neither life-threatening events nor significant respiratory or haemodynamic exacerbations during the flight. In a pandemic context, collective aero-MEDEVAC of ARDS Map and data Collective air medical evacuation: the French tool Evacuation of the ICU: care of the critically ill and injured during pandemics and disasters: CHEST consensus statement Short-term outcomes and mortality after interhospital intensive care transportation: an observational prospective cohort study of 368 consecutive transports with a mobile intensive care unit Interhospital transfer: an independent risk factor for mortality in the surgical intensive care unit Interhospital transportation of patients with severe lung failure on pumpless extracorporeal lung assist Quality of inter-hospital transportation in 431 transport survivor patients suffering from acute respiratory distress syndrome referred to specialist centers Acute Respiratory Distress Syndrome in the forward environment. Retrospective analysis of ARDS cases among French Army war casualties Ten Years of En Route Critical Care Training A new method of classifying prognostic comorbidity in longitudinal studies: development and validation The SOFA (Sepsis-related Organ Failure Assessment) score to describe organ dysfunction/failure. On behalf of the Working Group on Sepsis-Related Problems of the European Society of Intensive Care Medicine Acute respiratory distress syndrome: the Berlin Definition Monitoring sedation status over time in ICU patients: reliability and validity of the Richmond Agitation-Sedation Scale (RASS) Risk Factors Associated with Acute Respiratory Distress Syndrome and Death in Patients With Coronavirus Disease Clinical course and outcomes of critically ill patients with SARS-CoV-2 pneumonia in Wuhan, China: a single-centered, retrospective, observational study Clinical features of patients infected with 2019 novel coronavirus in Wuhan, China Clinical course and risk factors for mortality of adult inpatients with COVID-19 in Wuhan, China: a retrospective cohort study Short-term outcomes and mortality after interhospital intensive care transportation: an observational prospective cohort study of 368 consecutive transports with a mobile intensive care unit List of COVID-19: coronavirus disease 2019 ICU: intensive care unit MEDEVAC: medical evacuation MoRPHEE: Module de Réanimation pour Patient à Haute Elongation d'Evacuation PEEP: positive end-expiratory pressure PBW: predicted body weight SARS-CoV-2: severe acute respiratory syndrome coronavirus SOFA: Sequential Organ Failure Assessment The authors acknowledge the patients, all the health professionals who participated to the management of the patients before, during and after the aeromedical evacuations, and all the colleagues from French Air Force and French Military Health Service without whom these collective MEDEVACs could not be performed.