Derivation and validation of a risk-stratification model for patients with probable or proven COVID-19 in EDs: the revised HOME-CoV score.

BACKGROUND: The HOME-CoV (Hospitalisation or Outpatient ManagEment of patients with SARS-CoV-2 infection) score is a validated list of uniquely clinical criteria indicating which patients with probable or proven COVID-19 can be treated at home. The aim of this study was to optimise the score to improve its ability to discriminate between patients who do and do not need admission. METHODS: A revised HOME-CoV score was derived using data from a previous prospective multicentre study which evaluated the original Home-CoV score. Patients with proven or probable COVID-19 attending 34 EDs in France, Monaco and Belgium between April and May 2020 were included. The population was split into a derivation and validation sample corresponding to the observational and interventional phases of the original study. The main outcome was non-invasive or invasive ventilation or all-cause death within 7 days following inclusion. Two threshold values were defined using a sensitivity of >0.9 and a specificity of >0.9 to identify low-risk and high-risk patients, respectively. The revised HOME-CoV score was then validated by retrospectively applying it to patients in the same EDs with proven or probable COVID-19 during the interventional phase. The revised HOME-CoV score was also tested against original HOME-CoV, qCSI, qSOFA, CRB65 and SMART-COP in this validation cohort. RESULTS: There were 1696 patients in the derivation cohort, of whom 65 (3.8%) required non-invasive ventilation or mechanical ventilation or died within 7 days and 1304 patients in the validation cohort, of whom 22 (1.7%) had a progression of illness. The revised score included seven clinical criteria. The area under the curve (AUC) was 87.6 (95% CI 84.7 to 90.6). The cut-offs to define low-risk and high-risk patients were <2 and >3, respectively. In the validation cohort, the AUC was 85.8 (95% CI 80.6 to 91.0). A score of <2 qualified 73% of patients as low risk with a sensitivity of 0.77 (0.55-0.92) and a negative predictive value of 0.99 (0.99-1.00). CONCLUSION: The revised HOME-CoV score, which does not require laboratory testing, may allow accurate risk stratification and safely qualify a significant proportion of patients with probable or proven COVID-19 for home treatment.

Overcrowding in the Dispatching Centre During the COVID-19 Crisis: Are Medical Students a Resource?

INTRODUCTION: In February, the emergence of COronaVIrus Disease 2019 (COVID - 19) in France made it necessary to rapidly adapt emergency and SAMU services in order to take care of many infected patients. To respond to the increase in the number of calls in the dispatch centers, reinforcements were necessary on the fronts of the Medical Regulation Assistants (ARM). The aim of this study was to assess the relevance of medical students' responses to first calls exclusively concerning COVID-19. METHODS: This prospective, observational cohort study was carried out at the University Hospital Centre (CHU) in Angers. Twenty medical students mostly in the 5th year were voluntarily enrolled in the first line COVID-19 call taker team. Calls on the 1st, 3rd, and 5th starting day for each medical student, and randomly selected calls from the experienced first-line call taker were listened to by a medical expert to assess the adequate level of prioritization and orientation (emergency physician or general practitioner). The percentage of agreement between the expert, students, and experienced first-line call handlers were assessed. All participants gave their free consent to participate. The study was approved by the Ethics Committee of Angers (N° 2020-48). RESULTS: From March 18 to April 23, 2020, 302 calls from medical students (n = 20 students) and 40 calls from experienced first-line call handlers were analyzed. The average prioritization agreement rate between the expert and students was 76.16% (95% Confidence Interval: 71.04 to 80.62%) (n = 230/302) compared to 87.50% (95% CI: 73.9 to 94.5%) (n = 45/50) for the experienced first-line call handlers (P = 0.15). Medical students took more time per call with an absolute difference of 2 minutes 16 seconds (P < 0.001). CONCLUSION: The lessons to be observed from this COVID-19 crisis are that in the early days of increasing calls heralding a strain on the healthcare system, support by medical students must be considered.

Impact of piperaquine resistance in Plasmodium falciparum on malaria treatment effectiveness in The Guianas: a descriptive epidemiological study.

BACKGROUND: Plasmodium falciparum is an apicomplexan parasite responsible for lethal cases of malaria. According to WHO recommendations, P falciparum cases are treated with artemisinin-based combination therapy including dihydroartemisinin-piperaquine. However, the emergence of resistant parasites against dihydroartemisinin-piperaquine was reported in southeast Asia in 2008 and, a few years later, suspected in South America. METHODS: To characterise resistance emergence, a treatment efficacy study was performed on the reported patients infected with P falciparum and treated with dihydroartemisinin-piperaquine in French Guiana (n=6, 2016-18). Contemporary isolates collected in French Guiana were genotyped for P falciparum chloroquine resistance transporter (pfCRT; n=845) and pfpm2 and pfpm3 copy number (n=231), phenotyped using the in vitro piperaquine survival assay (n=86), and analysed through genomic studies (n=50). Additional samples from five Amazonian countries and one outside the region were genotyped (n=1440). FINDINGS: In field isolates, 40 (47%) of 86 (95% CI 35·9-57·1) were resistant to piperaquine in vitro; these phenotypes were more associated with pfCRTC350R (ie, Cys350Arg) and pfpm2 and pfpm3 amplifications (Dunn test, p<0·001). Those markers were also associated with dihydroartemisinin-piperaquine treatment failure (n=3 [50%] of 6). A high prevalence of piperaquine resistance markers was observed in Suriname in 19 (83%) of 35 isolates and in Guyana in 579 (73%) of 791 isolates. The pfCRTC350R mutation emerged before pfpm2 and pfpm3 amplification in a temporal sequence different from southeast Asia, and in the absence of artemisinin partial resistance, suggesting a geographically distinctive epistatic relationship between these genetic markers. INTERPRETATION: The high prevalence of piperaquine resistance markers in parasite populations of the Guianas, and the risk of associated therapeutic failures calls for caution on dihydroartemisinin-piperaquine use in the region. Furthermore, greater attention should be given to potential differences in genotype to phenotype mapping across genetically distinct parasite populations from different continents. FUNDING: Pan American Health Organization and WHO, French Ministry for Research, European Commission, Santé publique France, Agence Nationale de la Recherche, Fundação de Amparo à Pesquisa do Estado do Amazonas, Ministry of Health of Brazil, Oswaldo Cruz Foundation, and National Institutes of Health. TRANSLATIONS: For the French and Portuguese translations of the abstract see Supplementary Materials section.

Comparison of chest compression quality between the overlapping hands and interlocking hands techniques: A randomised cross-over trial.

BACKGROUND: Performing quality chest compressions is fundamental to the management of cardiopulmonary arrest. The aim of this study was to compare the efficacy of two hand positions: overlapping versus interlocking for performing chest compressions during cardiopulmonary arrest. METHODS: The HP2C (for Hands Position and Chest Compression) was a prospective, randomised, open-label, cross-over, single-centre study. Participants were recruited from the Emergency Medical Service (EMS) teams and the prehospital firefighter teams. They were randomised to start chest compressions either with overlapping or interlocking hands and then performed the other technique after a washout period. The judgement criteria were the overall chest compressions success score generated by software in accordance with ILCOR recommendations, the quality of compression, release, rate and subjective intensity measured with the Borg scale. RESULTS: A total of 100 participants were included in the study. The mean age of the caregivers was 38 ± 9.3 years. The median CPR score was 79.5% IQR [48.5-94.0] in the overlapping hands group and 71% IQR [38.0-92.8] in the interlocking hands group (p-value = 0.37). There was no significant difference for the other criteria, especially no difference in term of intensity of effort. However, there was a trend towards better results with overlapping hands. CONCLUSIONS: This study failed to demonstrate a difference in effectiveness between overlapping and interlocking hand chest compressions during cardiopulmonary resuscitation.

A new reservoir-based CPAP with low oxygen consumption: the Bag-CPAP.

BACKGROUND: Several noninvasive ventilatory supports rely in their design on high oxygen consumption which may precipitate oxygen shortage, as experienced during the COVID-19 pandemic. In this bench-to-bedside study, we assessed the performance of a new continuous positive airway pressure (CPAP) device integrating a large reservoir ("Bag-CPAP") designed to minimize oxygen consumption, and compared it with other CPAP devices. METHODS: First, a bench study compared the performances of Bag-CPAP and four CPAP devices with an intensive care unit ventilator. Two FiO2 targets (40-60% and 80-100%) at a predefined positive end expiratory pressure (PEEP) level between 5 and 10 cm H2O were tested and fraction of inspired oxygen (FiO2) and oxygen consumption were measured. Device-imposed work of breathing (WOB) was also evaluated. Second, an observational clinical study evaluated the new CPAP in 20 adult patients with acute respiratory failure in two hospitals in France. Actual FiO2, PEEP, peripheral oxygen saturation, respiratory rate, and dyspnea score were assessed. RESULTS: All six systems tested in the bench study reached the minimal FiO2 target of 40% and four reached at least 80% FiO2 while maintaining PEEP in the predefined range. Device-delivered FiO2/consumed oxygen ratio was the highest with the new reservoir-based CPAP irrespective of FiO2 target. WOB induced by the device was higher with Bag-CPAP. In the clinical study, Bag-CPAP was well tolerated and could reach high (> 90%) and moderate (> 50%) FiO2 with an oxygen flow rate of 15 [15-16] and 8 [7-9] L/min, respectively. Dyspnea score improved significantly after introduction of Bag-CPAP, and SpO2 increased. CONCLUSIONS: In vitro, Bag-CPAP exhibited the highest oxygen saving properties albeit had increased WOB. It was well accepted clinically and reduced dyspnea. Bag-CPAP may be useful to treat patients with acute respiratory failure in the field, especially when facing constraints in oxygen delivery.

Point-of-care ultrasonography for risk stratification of non-critical suspected COVID-19 patients on admission (POCUSCO): A prospective binational study.

BACKGROUND: Lung point-of-care ultrasonography (L-POCUS) is highly effective in detecting pulmonary peripheral patterns and may allow early identification of patients who are likely to develop an acute respiratory distress syndrome (ARDS). We hypothesized that L-POCUS performed within the first 48 hours of non-critical patients with suspected COVID-19 would identify those with a high-risk of worsening. METHODS: POCUSCO was a prospective, multicenter study. Non-critical adult patients who presented to the emergency department (ED) for suspected or confirmed COVID-19 were included and had L-POCUS performed within 48 hours following ED presentation. The lung damage severity was assessed using a previously developed score reflecting both the extension and the intensity of lung damage. The primary outcome was the rate of patients requiring intubation or who died within 14 days following inclusion. RESULTS: Among 296 patients, 8 (2.7%) met the primary outcome. The area under the curve (AUC) of L-POCUS was 0.80 [95%CI:0.60-0.94]. The score values which achieved a sensibility >95% in defining low-risk patients and a specificity >95% in defining high-risk patients were <1 and ≥16, respectively. The rate of patients with an unfavorable outcome was 0/95 (0%[95%CI:0-3.9]) for low-risk patients (score = 0), 4/184 (2.17%[95%CI:0.8-5.5]) for intermediate-risk patients (score 1-15) and 4/17 (23.5%[95%CI:11.4-42.4]) for high-risk patients (score ≥16). In confirmed COVID-19 patients (n = 58), the AUC of L-POCUS was 0.97 [95%CI:0.92-1.00]. CONCLUSION: L-POCUS performed within the first 48 hours following ED presentation allows risk-stratification of patients with non-severe COVID-19.

Cardiac Arrest Management in the Workplace: Improving but Not Enough?

The aim was to describe out-of-hospital cardiac arrest (OHCA) occurring in the workplace of a large emergency network, and compare the evolution of their management in the last 15 years. A retrospective study based on data from the Northern Alps Emergency Network compared characteristics of OHCA between cases in and out the workplace, and between cases occurring from January 2004 to December 2010 and from January 2011 to December 2017. Among the 15,320 OHCA cases included, 320 occurred in the workplace (2.1%). They were more often in younger men, and happened more frequently in an area with access to public defibrillation, had more often a shockable rhythm, had a cardiopulmonary resuscitation started by a bystander more frequently, and had a better outcome. Cardiopulmonary resuscitation started by a bystander was the only chain of survival link that improved for cases occurring after December 2010. Workplace OHCA seems to be managed more effectively than others; however, only a slight survival improvement was observed, suggesting that progress is still needed.

Prevalence and characterization of forgoing care: comparison of two prospective multicentre cohorts between pre-COVID-19 era and a lockdown period.

BACKGROUND: Little is known about patients who forego healthcare, although it is an important provider of unfavorable health-related outcomes. Forgoing healthcare characterizes situations in which people do not initiate or interrupt a care process, even though they perceive the need for it, whether or not this need is medically proven. The aims of this study were to assess the prevalence and the determinants of patients who forego healthcare. The second aim was to compare the characteristics of patients who gave up healthcare during the French lockdown due to COVID-19. METHODS: We conducted two multicenter cross-sectional studies in 2017 and 2020 carried out in French patients presenting to the emergency departments. Patients who gave their consent to participate were interviewed with a standardized questionnaire. It consisted of two parts: epidemiological characteristics and health care refusal. A third part concerning the renunciation of care during the COVID-19 period was added to the second study period. RESULTS: A total of 1878 patients had completed the questionnaire during the interview with the physicians, 900 during the first period in 2017 (47.9%) and 978 (52.1%) during the second period. A total of 401/1878 patients reported not seeking care in the last 12 months (21.4% [95%CI: 19.5-23.3%]). In 2020, patients forewent care more during the confinement period than outside with different characteristics of the foregoing care populations. CONCLUSION: Forgoing care is common in a universal health care system such as France's and increased during the pandemic. Key public health messages targeted at the reasons for not seeking care must now be disseminated in order to combat this.

Impact of Specific Emergency Measures on Survival in Out-of-Hospital Traumatic Cardiac Arrest.

INTRODUCTION: The management of out-of-hospital traumatic cardiac arrest (TCA) for professional rescuers entails Advanced Life Support (ALS) with specific actions to treat the potential reversible causes of the arrest: hypovolemia, hypoxemia, tension pneumothorax (TPx), and tamponade. The aim of this study was to assess the impact of specific rescue measures on short-term outcomes in the context of resuscitating patients with a TCA. METHODS: This retrospective study concerns all TCA patients treated in two emergency medical units, which are part of the Northern French Alps Emergency Network (RENAU), from January 2004 through December 2017. Utstein variables and specific rescue measures in TCA were compiled: fluid expansion, pelvic stabilization, tourniquet application, bilateral thoracostomy, and thoracotomy procedures. The primary endpoint was survival rate at Day 30 with good neurological status (Cerebral Performance Category [CPC] score CPC 1 and CPC 2). RESULTS: In total, 287 resuscitation attempts in TCA were included and 279 specific interventions were identified: 262 fluid expansions, 41 pelvic stabilizations, five tourniquets, and 175 bilateral thoracostomies (including 44 with TPx). CONCLUSION: Among the standard resuscitation measures to treat the reversible causes of cardiac arrest, this study found that bilateral thoracostomy and tourniquet application on a limb hemorrhage improve survival in TCA. A larger sample for pelvic stabilization is needed.

Risk of symptomatic venous thromboembolism in mild and moderate COVID-19: A comparison of two prospective European cohorts.

BACKGROUND: Severely ill patients with SARS-CoV-2 have an increased risk of venous thromboembolism (VTE) i.e., deep vein thrombosis and pulmonary embolism. However, the VTE risk in patients with mild and moderate COVID-19, hospitalized or managed at home, remain uncertain. The aims of this study were to assess the rate and the risk factors symptomatic VTE, in patients with mild and moderate COVID-19 and to compare them to a cohort of similar patients without COVID-19. METHODS: Patients presenting to the emergency department (ED) of participating centers for confirmed or probable mild or moderate COVID-19 and not having acute VTE were included. This COVID-19 cohort was retrospectively compared to a prospective cohort of similar ED patients using propensity score matching. The main outcome was the rate of symptomatic VTE within the 28 days after ED presentation. RESULTS: A total of 2292 patients were included in the COVID-19 cohort. The 28-day incidence of symptomatic VTE was 1.3% (n = 29/2292, 95%CI: 0.9 to 1.8), 2.3% (n = 20/866, 95%CI: 1.5 to 3.5) in moderate COVID-19 patients and 0.6% (n = 9/1426; 95%CI: 0.3 to 1.2) in mild COVID-19 patients managed as outpatients. An age over 65 years and hospitalization were independent risk factors of VTE. After adjustment, patients in the COVID-19 cohort had an absolute increase in over symptomatic VTE risk of +1.69% (95%CI, 0.88 to 2.51) versus patients in the comparison cohort (n = 1539). CONCLUSIONS: Patients with moderate COVID-19 presenting to the ED had a high risk of subsequent VTE. TRIAL REGISTRATION: Ethics committee of the CHU of Angers (N°2020/87).

Interhospital transfer of COVID-19 patients treated with high-flow nasal oxygen therapy.

At the start of the COVID-19 pandemic, early intubation was recommended on the basis of worldwide observations of severe hypoxemia. However, some patients were ultimately able to benefit from high-flow nasal cannula (HFNC) and thus avoid intubation. During the "second wave" (September to December 2020 in France), some emergency departments implemented HFNC in patients with severe COVID-19. The question then arose regarding the transfer of these most serious patients to intensive care units (ICU) and of the respiratory modalities to be used during this transfer. To assess the feasibility of interhospital transfers of COVID-19 patients needing HFNC, we conducted a bi-centric prospective observational study of all medical transfers of patients needing HFNC with the Chambéry and Angers (France) mobile emergency and intensive care service (SMUR) during the "second wave" of the COVID-19 pandemic in France. Analysis of these 42 patients showed no significant variation in the respiratory requirements during the transfer. Overall, 52% of patients were intubated during their stay in ICU, including three patients intubated before or during transfer. Interhospital transfer with HFNC is very high-risk, and intubation remains indicated in the most unstable patients. However, 48% of patients benefited from HFNC and were thus able to avoid intubation during their transfer and ICU stay; for these patients, intubation would probably have been indicated in the absence of available HFNC techniques.

Adaptation of ED design layout during the COVID-19 pandemic: a national cross-sectional survey.

BACKGROUND: The aim was to describe the organisational changes in French EDs in response to the COVID-19 pandemic with regard to architectural constraints and compare with the recommendations of the various bodies concerning the structural adjustments to be made in this context. METHODS: As part of this cross-sectional study, all heads of emergency services or their deputies were contacted to complete an electronic survey. This was a standardised online questionnaire consisting of four parts: characteristics of the responding centre, creation of the COVID-19 zone and activation of the hospital's emergency operations plan, flow and circulation of patients and, finally, staff management. Each centre was classified according to its workload related to COVID-19 and its size (university hospital centre, high-capacity hospital centre and low-capacity hospital centre). The main endpoint was the frequency of implementation of international guidelines for ED organisation. RESULTS: Between 11 May and 20 June 2020, 57 French EDs completed the online questionnaire and were included in the analysis. Twenty-eight EDs were able to separate patient flows into two zones: high and low viral density (n=28/57, 49.1%). Of the centres included, 52.6% set up a specific triage area for patients with suspected COVID-19 (n=30/57). Whereas, in 15 of the EDs (26.3%), the architecture made it impossible to increase the surface area of the ED. CONCLUSION: All EDs have adapted, but many of the changes recommended for the organisation of ED could not be implemented. ED architecture constrains adaptive capacities in the context of COVID-19.

Acting on the potentially reversible causes of traumatic cardiac arrest: Possible but not sufficient.

INTRODUCTION: Traumatic cardiac arrest (TCA) guidelines emphasize specific actions that aim to treat the potential reversible causes of the arrest. The aim of this study was to measure the impact of these recommendations on specific rescue measures carried out in the field, and their influence on short-term outcomes in the resuscitation of TCA patients. METHODS: We conducted a retrospective study of all TCA patients treated in two emergency medical units, which are part of the Northern Alps Emergency Network, from January 2004 to December 2017. We categorised cases into three periods: pre-guidelines (from January 2004 to December 2007), during guidelines (from January 2008 to December 2011), and post-guidelines (from January 2012 to December 2017). Local guidelines, a physician education programme, and specific training were set up during the post-guidelines period to increase adherence to recommendations. Utstein variables, and specific rescue measures were collected: advanced airway management, fluid administration, pelvic stabilisation or tourniquet application, bilateral thoracostomy, and thoracotomy procedures. The primary endpoint was survival rate at day 30 with good neurological status (cerebral performance category scores 1 & 2) in each period, considering the pre-guidelines period as the reference. RESULTS: There were 287 resuscitation attempts in the TCA cases included, and 279 specific interventions were identified with a significant increase in the number of fluid expansions (+16%), bilateral thoracostomies (+75%), and pelvic stabilisations (+25%) from the pre- to post-guidelines periods. However, no improvement in survival over time was found. CONCLUSION: Reversible measures were applied but to a varying degree, and may not adequately capture pre-hospital performance on overall TCA survival.

Outpatient Management of Patients With COVID-19: Multicenter Prospective Validation of the Hospitalization or Outpatient Management of Patients With SARS-CoV-2 Infection Rule to Discharge Patients Safely.

BACKGROUND: The Hospitalization or Outpatient Management of Patients With SARS-CoV-2 Infection (HOME-CoV) rule is a checklist of eligibility criteria for home treatment of patients with COVID-19, defined using a Delphi method. RESEARCH QUESTION: Is the HOME-CoV rule reliable for identifying a subgroup of COVID-19 patients with a low risk of adverse outcomes who can be treated at home safely? STUDY DESIGN AND METHODS: We aimed to validate the HOME-CoV rule in a prospective, multicenter study before and after trial of patients with probable or confirmed COVID-19 who sought treatment at the ED of 34 hospitals. The main outcome was an adverse evolution, that is, invasive ventilation or death, occurring within the 7 days after patient admission. The performance of the rule was assessed by the false-negative rate. The impact of the rule implementation was assessed by the absolute differences in the rate of patients who required invasive ventilation or who died and in the rate of patients treated at home, between an observational and an interventional period after implementation of the HOME-CoV rule, with propensity score adjustment. RESULTS: Among 3,000 prospectively enrolled patients, 1,239 (41.3%) demonstrated a negative HOME-CoV rule finding. The false-negative rate of the HOME-CoV rule was 4 in 1,239 (0.32%; 95% CI, 0.13%-0.84%), and its area under the receiver operating characteristic curve was 80.9 (95% CI, 76.5-85.2). On the adjusted populations, 25 of 1,274 patients (1.95%) experienced an adverse evolution during the observational period vs 12 of 1,274 patients (0.95%) during the interventional period: -1.00 (95% CI, -1.86 to -0.15). During the observational period, 858 patients (67.35%) were treated at home vs 871 patients (68.37%) during the interventional period: -1.02 (95% CI, -4.46 to 2.26). INTERPRETATION: A large proportion of patients treated in the ED with probable or confirmed COVID-19 have a negative HOME-CoV rule finding and can be treated safely at home with a very low risk of complications. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT04338841; URL: www.clinicaltrials.gov.

Continuous positive airway pressure for respiratory support during COVID-19 pandemic: a frugal approach from bench to bedside.

BACKGROUND: We describe a frugal approach (focusing on needs, performance, and costs) to manage a massive influx of COVID-19 patients with acute hypoxemic respiratory failure (AHRF) using the Boussignac valve protected by a filter ("Filter Frugal CPAP", FF-CPAP) in and out the ICU. METHODS: (1) A bench study measured the impact of two filters with different mechanical properties on CPAP performances, and pressures were also measured in patients. (2) Non-ICU healthcare staff working in COVID-19 intermediate care units were trained with a video tutorial posted on a massive open online course. (3) A clinical study assessed the feasibility and safety of using FF-CPAP to maintain oxygenation and manage patients out of the ICU during a massive outbreak. RESULTS: Bench assessments showed that adding a filter did not affect the effective pressure delivered to the patient. The resistive load induced by the filter variably increased the simulated patient's work of breathing (6-34%) needed to sustain the tidal volume, depending on the filter's resistance, respiratory mechanics and basal inspiratory effort. In patients, FF-CPAP achieved pressures similar to those obtained on the bench. The massive training tool provided precious information on the use of Boussignac FF-CPAP on COVID-19 patients. Then 85 COVID-19 patients with ICU admission criteria over a 1-month period were studied upon FF-CPAP initiation for AHRF. FF-CPAP significantly decreased respiratory rate and increased SpO2. Thirty-six (43%) patients presented with respiratory indications for intubation prior to FF-CPAP initiation, and 13 (36%) of them improved without intubation. Overall, 31 patients (36%) improved with FF-CPAP alone and 17 patients (20%) did not require ICU admission. Patients with a respiratory rate > 32 breaths/min upon FF-CPAP initiation had a higher cumulative probability of intubation (p < 0.001 by log-rank test). CONCLUSION: Adding a filter to the Boussignac valve does not affect the delivered pressure but may variably increase the resistive load depending on the filter used. Clinical assessment suggests that FF-CPAP is a frugal solution to provide a ventilatory support and improve oxygenation to numerous patients suffering from AHRF in the context of a massive outbreak.