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 SpO 2 . 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. Supplementary Information The online version contains supplementary material available at 10.1186/s13613-021-00828-2.
【저자키워드】 COVID-19, Acute hypoxemic respiratory failure, Continuous Positive Airway Pressure, Frugal innovation, 【초록키워드】 Respiratory failure, feasibility, intubation, ICU, outbreak, healthcare, Patient, ICU admission, assessment, information, Care, patients, COVID-19 patients, clinical study, CPAP, COVID-19 patient, respiratory rate, Oxygenation, criteria, Respiratory mechanics, ventilatory support, clinical assessment, Volume, Inspiratory effort, AHRF, supplementary material, log-rank test, indication, hypoxemic, Work of breathing, approach, effective, IMPROVE, cumulative probability, Course, Result, significantly, the patient, provided, maintain, not affect, Adding, Bench, 【제목키워드】 Respiratory Support, positive airway pressure, approach, Continuous,