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Open accessJournal ArticleDOI: 10.1186/S13613-021-00828-2

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

02 Mar 2021-Annals of Intensive Care (SpringerOpen)-Vol. 11, Iss: 1, pp 38-38
Abstract: 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. (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. 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). 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.

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5 results found

Open accessJournal ArticleDOI: 10.3390/JCM10122738
Abstract: Patients with severe lung injury usually have a high respiratory drive, resulting in intense inspiratory effort that may even worsen lung damage by several mechanisms gathered under the name "patient-self inflicted lung injury" (P-SILI). Even though no clinical study has yet demonstrated that a ventilatory strategy to limit the risk of P-SILI can improve the outcome, the concept of P-SILI relies on sound physiological reasoning, an accumulation of clinical observations and some consistent experimental data. In this review, we detail the main pathophysiological mechanisms by which the patient's respiratory effort could become deleterious: excessive transpulmonary pressure resulting in over-distension; inhomogeneous distribution of transpulmonary pressure variations across the lung leading to cyclic opening/closing of nondependent regions and pendelluft phenomenon; increase in the transvascular pressure favoring the aggravation of pulmonary edema. We also describe potentially harmful patient-ventilator interactions. Finally, we discuss in a practical way how to detect in the clinical setting situations at risk for P-SILI and to what extent this recognition can help personalize the treatment strategy.

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Topics: Lung injury (66%), Transpulmonary pressure (55%)

Open accessPosted ContentDOI: 10.1101/2021.06.17.21258809
22 Jun 2021-medRxiv
Abstract: Introduction Covid19 Acute Respiratory Distress Syndrome (CARDS) poses a challenge in management particularly due to limited capacity of ventilated intensive care beds and staffing, and this is exacerbated in resource poor settings with poor patient outcomes. Within this context CPAP has been trialled for CARDS although mainly in resource rich settings. Methods This study retrospectively analyses the survival outcomes and characteristics of a cohort of patients with moderate to severe CARDS were treated exclusively with CPAP in a rural secondary level hospital in Pakistan with limited previous critical care expertise. Results 32 out of the 41 patients (78%) who were treated with CPAP survived overall (30/37 (81%) who were treated according to protocol). Discussion Results suggest non inferiority to CARDS outcomes of critical care units employing Intubation and Mechanical Ventilation (IMV) in resource rich settings. CPAP should be promoted as an efficacious and cost-effective method for treating CARDS within the context of the pandemic surge of Covid19 in resource poor settings. Key Messages What is the key question? Is Continuous Positive Airway Pressure (CPAP) an effective treatment for Covid19 Acute Respiratory Distress Syndrome (CARDS) in a resource poor setting in a pandemic surge context? What is the bottom line? Survival rate for CARDS on CPAP in our single centre retrospective cohort study is 78% which is similar to outcomes from critical care centres in resource rich settings employing Intubation and Mechanical Ventilation (IMV) and better than outcomes in many critical care centres in resource poor settings. This suggests CPAP should be promoted as an efficacious and cost-effective method for managing the pandemic surge of CARDS in resource poor settings. Why read on? The current surge of Covid19 CARDS in resource poor settings poses a significant challenge in terms of effective management given cost and resource restraints, reflected by poor outcomes in overwhelmed critical care centres employing IMV. This is the largest study so far documenting the survival outcomes and characteristics of patients with CARDS treated exclusively with CPAP within a resource poor setting.

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Topics: Intensive care (55%)

Open accessJournal ArticleDOI: 10.1016/S2213-2600(21)00414-8
Abstract: Non-invasive respiratory support (NIRS) has increasingly been used in the management of COVID-19-associated acute respiratory failure, but questions remain about the utility, safety, and outcome benefit of NIRS strategies. We identified two randomised controlled trials and 83 observational studies, compromising 13 931 patients, that examined the effects of NIRS modalities-high-flow nasal oxygen, continuous positive airway pressure, and bilevel positive airway pressure-on patients with COVID-19. Of 5120 patients who were candidates for full treatment escalation, 1880 (37%) progressed to invasive mechanical ventilation and 3658 of 4669 (78%) survived to study end. Survival was 30% among the 1050 patients for whom NIRS was the stated ceiling of treatment. The two randomised controlled trials indicate superiority of non-invasive ventilation over high-flow nasal oxygen in reducing the need for intubation. Reported complication rates were low. Overall, the studies indicate that NIRS in patients with COVID-19 is safe, improves resource utilisation, and might be associated with better outcomes. To guide clinical decision making, prospective, randomised studies are needed to address timing of intervention, optimal use of NIRS modalities-alone or in combination-and validation of tools such as oxygenation indices, response to a trial of NIRS, and inflammatory markers as predictors of treatment success.

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32 results found

Open accessJournal ArticleDOI: 10.1016/S2213-2600(20)30076-X
Zhe Xu1, Lei Shi1, Yijin Wang, Ji-Yuan Zhang1  +14 moreInstitutions (1)
Abstract: bPortuguese Abstract:O surto do novo coronavírus (COVID-19) em Wuhan, China, iniciado em dezembro de 2019, evoluiu para se tornar uma pandemia global A

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5,215 Citations

Open accessJournal ArticleDOI: 10.1056/NEJMOA2004500
Abstract: Background Community transmission of coronavirus 2019 (Covid-19) was detected in the state of Washington in February 2020. Methods We identified patients from nine Seattle-area hospitals w...

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1,696 Citations

Open accessJournal ArticleDOI: 10.1001/JAMA.2020.4326
Matt Arentz1, Eric Yim, Lindy Klaff, Sharukh Lokhandwala  +3 moreInstitutions (1)
28 Apr 2020-JAMA
Abstract: This case series describes the clinical presentation, characteristics, and outcomes of patients with coronavirus disease 2019 (COVID-19) admitted to the intensive care unit at a public hospital in Washington State in February 2020, including initial reports of cardiomyopathy in one-third of the patients.

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Topics: Intensive care unit (52%)

1,487 Citations

Journal ArticleDOI: 10.1056/NEJMOA1503326
Abstract: BACKGROUND Whether noninvasive ventilation should be administered in patients with acute hypoxemic respiratory failure is debated. Therapy with high-flow oxygen through a nasal cannula may offer an alternative in patients with hypoxemia. METHODS We performed a multicenter, open-label trial in which we randomly assigned patients without hypercapnia who had acute hypoxemic respiratory failure and a ratio of the partial pressure of arterial oxygen to the fraction of inspired oxygen of 300 mm Hg or less to high-flow oxygen therapy, standard oxygen therapy delivered through a face mask, or noninvasive positive-pressure ventilation. The primary outcome was the proportion of patients intubated at day 28; secondary outcomes included all-cause mortality in the intensive care unit and at 90 days and the number of ventilator-free days at day 28. RESULTS A total of 310 patients were included in the analyses. The intubation rate (primary outcome) was 38% (40 of 106 patients) in the high-flow–oxygen group, 47% (44 of 94) in the standard group, and 50% (55 of 110) in the noninvasive-ventilation group (P = 0.18 for all comparisons). The number of ventilator-free days at day 28 was significantly higher in the high-flow–oxygen group (24±8 days, vs. 22±10 in the standard-oxygen group and 19±12 in the noninvasive-ventilation group; P = 0.02 for all comparisons). The hazard ratio for death at 90 days was 2.01 (95% confidence interval [CI], 1.01 to 3.99) with standard oxygen versus high-flow oxygen (P = 0.046) and 2.50 (95% CI, 1.31 to 4.78) with noninvasive ventilation versus high-flow oxygen (P = 0.006). CONCLUSIONS In patients with nonhypercapnic acute hypoxemic respiratory failure, treatment with high-flow oxygen, standard oxygen, or noninvasive ventilation did not result in significantly different intubation rates. There was a significant difference in favor of high-flow oxygen in 90-day mortality. (Funded by the Programme Hospitalier de Recherche Clinique Interregional 2010 of the French Ministry of Health; FLORALI number, NCT01320384.)

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Topics: Fraction of inspired oxygen (69%), Oxygen therapy (64%), Nasal cannula (62%) ... show more

1,185 Citations

Open accessJournal ArticleDOI: 10.1016/S0140-6736(20)31189-2
06 Jun 2020-The Lancet
Abstract: Background Over 40 000 patients with COVID-19 have been hospitalised in New York City (NY, USA) as of April 28, 2020. Data on the epidemiology, clinical course, and outcomes of critically ill patients with COVID-19 in this setting are needed. Methods This prospective observational cohort study took place at two NewYork-Presbyterian hospitals affiliated with Columbia University Irving Medical Center in northern Manhattan. We prospectively identified adult patients (aged ≥18 years) admitted to both hospitals from March 2 to April 1, 2020, who were diagnosed with laboratory-confirmed COVID-19 and were critically ill with acute hypoxaemic respiratory failure, and collected clinical, biomarker, and treatment data. The primary outcome was the rate of in-hospital death. Secondary outcomes included frequency and duration of invasive mechanical ventilation, frequency of vasopressor use and renal replacement therapy, and time to in-hospital clinical deterioration following admission. The relation between clinical risk factors, biomarkers, and in-hospital mortality was modelled using Cox proportional hazards regression. Follow-up time was right-censored on April 28, 2020 so that each patient had at least 28 days of observation. Findings Between March 2 and April 1, 2020, 1150 adults were admitted to both hospitals with laboratory-confirmed COVID-19, of which 257 (22%) were critically ill. The median age of patients was 62 years (IQR 51-72), 171 (67%) were men. 212 (82%) patients had at least one chronic illness, the most common of which were hypertension (162 [63%]) and diabetes (92 [36%]). 119 (46%) patients had obesity. As of April 28, 2020, 101 (39%) patients had died and 94 (37%) remained hospitalised. 203 (79%) patients received invasive mechanical ventilation for a median of 18 days (IQR 9-28), 170 (66%) of 257 patients received vasopressors and 79 (31%) received renal replacement therapy. The median time to in-hospital deterioration was 3 days (IQR 1-6). In the multivariable Cox model, older age (adjusted hazard ratio [aHR] 1·31 [1·09-1·57] per 10-year increase), chronic cardiac disease (aHR 1·76 [1·08-2·86]), chronic pulmonary disease (aHR 2·94 [1·48-5·84]), higher concentrations of interleukin-6 (aHR 1·11 [95%CI 1·02-1·20] per decile increase), and higher concentrations of D-dimer (aHR 1·10 [1·01-1·19] per decile increase) were independently associated with in-hospital mortality. Interpretation Critical illness among patients hospitalised with COVID-19 in New York City is common and associated with a high frequency of invasive mechanical ventilation, extrapulmonary organ dysfunction, and substantial in-hospital mortality. Funding National Institute of Allergy and Infectious Diseases and the National Center for Advancing Translational Sciences, National Institutes of Health, and the Columbia University Irving Institute for Clinical and Translational Research.

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Topics: Cohort study (52%), Prospective cohort study (51%), Hazard ratio (51%) ... show more

1,089 Citations