Severity of respiratory failure and outcome of patients needing a ventilatory support in the Emergency Department during Italian novel coronavirus SARS-CoV2 outbreak: Preliminary data on the role of Helmet CPAP and Non-Invasive Positive Pressure Ventilation

Abstract

Background: Novel Coronavirus SARS-CoV-2 pandemic is spreading around the world. At the end of February, the outburst of the pandemic has hit hard on northern Italian's hospitals. As of today, no data have been published regarding the severity of respiratory failure of patients presenting to the Emergency Departments. Moreover, the outcome the patients forced to undergo Continuous Positive Airway Pressure (CPAP) or Non-Invasive Positive Pressure Ventilation (NIPPV) due to lack of Intensive Care resources is unknown. "Papa Giovanni XXIII" hospital (HPG23) of Bergamo is one of the largest hospitals in the Country, with an Emergency Department (ED) managing over 100,000 patients per year. Methods: This is a retrospective observational study based on chart review of patients presenting to the Emergency Department of HPG23 from 29/02/2020 to 10/03/2020 with a clinical condition highly suspicious for COVID-19 infection. Registration of admission rates, severity of respiratory failure (ARDS classification), need of respiratory support, SARS-CoV-2 PCR test and outcome of patients treated with a ventilatory support were registered on 10th of May 2020. Findings: From 29/02 to 10/03 611 patients with a suspected diagnosis of COVID-19 infection were evaluated in our ED; 320 (52%) met the criteria for hospital admission and 99 (31%) needed to be immediately started on ventilatory support (81% CPAP, 7% NIPPV, 12% Invasive Mechanical Ventilation). Eighty-five (86%) of the 99 patients needing a ventilatory support eventually had SARS-CoV-2 infection confirmed by PCR test on nasal-pharyngeal swab. Their median PO2/FiO2 ratio was 128 (IQR 85À168), with 23 patients (29.5%) classified as severe ARDS. Mortality rate as of 10th of May was 76.5%, ranging from 44.4% within patients <60 years old to 85% within those older than 60 years (p = 0.001). NIPPV/CPAP failure occurred in 91.5% of patients. Interpretation: The population of patients suspected for COVID-19 infection presenting at our ED showed a very high rate of severe respiratory failure, with urgent need of a large amount of intensive care resources. Mortality rates of critically ill patients with confirmed COVID-19 (76.5%) are similar to previously reported studies with similar population. CPAP/NIPPV could be a valid strategy to treat severely hypoxic patients that cannot be intubated in the ED due to lack of intensive care resources. Funding: No funds were received for this research project.

Continuous Positive Airway Pressure (CPAP) face-mask ventilation is an easy and cheap option to manage a massive influx of patients presenting acute respiratory failure during the SARS-CoV-2 outbreak: A retrospective cohort study

“…While CPAP in cardiogenic pulmonary oedema has been shown to reduce intubation rate [ 12 ], a randomized trial in acute hypoxemic respiratory failure, showed no effect of CPAP in reducing intubation rate and mortality, despite improved oxygenation [ 13 ]. However, during the Chinese and European COVID-19 outbreaks, a number of critical care teams proposed using high flow oxygen through nasal cannula (HFONC) or NIV at least for initial management [ 14 – 18 ]. Optimal respiratory support for COVID-19 patients presenting with acute hypoxemic respiratory failure, however, remains unknown.…”

Helmet CPAP&nbsp;to Treat Hypoxic Pneumonia Outside the ICU: An Observational Study During the COVID-19 Outbreak

“…[11] When treating COVID-19 affected patients, the use of helmets might bear the additional advantage of reducing virus environment contamination. [12,13] Recent reports suggest that helmet CPAP can be effective for COVID-19 treatment, [14][15][16] possibly combined with prone or lateral position. [17][18][19] In a multicenter cohort study Aliberti et al showed that helmet CPAP signi cantly increased PaO2/FiO2 from oxygen administration alone, but that treatment failure was frequent, occurring in 44% of patients who required intubation and invasive ventilation.…”

The variation of FiO2 with circuit type and peak inspiratory flow rate during non-invasive respiratory support using domiciliary ventilators and its significance during the COVID-19 pandemic

“…However, outcomes reported from CPAP therapy have been variable with mortality rates of 76% reported in one series. 5 Breathing circuits for NIV and CPAP use a viral filter placed at the patient end of the breathing circuit to allow scavenging of SARS-CoV-2 and reduce transmission to staff and other patients. This has been the subject of national UK guidance.…”

“…However, outcomes reported from CPAP therapy have been variable with mortality rates of 76% reported in one series. 5 …”

“… 8 This may in part explain poor outcomes with CPAP therapy delivered by domiciliary ventilators. 5 There have been several reports on social media platforms during the COVID-19 pandemic which have suggested that high FiO 2 (up to 0.85) is achievable with non-invasive CPAP and NIV. However these experiments are often conducted whilst breathing comfortably.…”