The experience of high-flow nasal cannula in hospitalized patients with 2019 novel coronavirus-infected pneumonia in two hospitals of Chongqing, China

Abstract

Background: The outbreak of a novel coronavirus (2019-nCoV)-infected pneumonia (NCIP) is currently ongoing in China. Most of the critically ill patients received high-flow nasal cannula (HFNC) oxygen therapy. However, the experience of HFNC in this population is lacking. Methods:We retrospectively screened 318 confirmed patients with NCIP in two hospitals of Chongqing, China, from January 1st to March 4th, 2020. Among them, 27 (8.4%) patients experienced severe acute respiratory failure including 17 patients (63%) treated with HFNC as first-line therapy, 9 patients (33%) treated with noninvasive ventilation (NIV) and one patient (4%) treated with invasive ventilation. HFNC failure was defined by the need of NIV or intubation as rescue therapy. Results:Of the 17 HFNC patients, 7 (41%) experienced HFNC failure. The HFNC failure rate was 0% (0/6) in patients with PaO 2 /FiO 2 > 200 mm Hg vs. 63% (7/11) in those with PaO 2 /FiO 2 ≤ 200 mm Hg (p = 0.04). Compared with baseline data, the respiratory rate significantly decreased after 1-2 h of HFNC in successful group , p = 0.03]. However, it did not in the unsuccessful group. After initiation of NIV as rescue therapy among the 7 patients with HFNC failure, PaO 2 /FiO 2 significantly improved after 1-2 h of NIV under HFNC, p = 0.04]. However, two out of seven (29%) patients with NIV as rescue therapy ultimately received intubation. Among the 27 patients with severe acute respiratory failure, four patients were eventually intubated (15%). Conclusions:Our study indicated that HFNC was the most common ventilation support for patients with NCIP. Patients with lower PaO 2 /FiO 2 were more likely to experience HFNC failure.

High-Flow Nasal Cannula therapy: A Feasible Treatment in Vulnerable Older COVID-19 Patients on the Wards

“…Success rate of HFNC seems to be mostly dependent on the severity of pulmonary infection, with lower PaO2/FiO2 ratios resulting in a higher chances of therapy failure. Wang et al [9] described failure of HFNC in 63% when PaO2/FiO2 was below 200 mmHg, comparable with our group. Previous studies have shown that vulnerability is associated with worse clinical outcomes including mortality and duration of hospitalization in non-COVID patients [18,19].…”

“…We found an overall case rate survival much lower than most reported survival rates on the clinical wards [6,16,17].However, our cohort is a selection of frail patients with severe respiratory failure and high ARDS scores. Recently two other studies were published describing the successful use of HFNC in COVID-19 patients [8,9]. Contrary to these studies, we did not use HFNC therapy as an intermediate step-up between invasive mechanical ventilation and conventional oxygen therapy.…”

“…The median time in days between onset of symptoms and hospital admission was six (4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14). Nearly all patients reported cough (91%) and dyspnea (84%) on admission.…”

“…Nurses and staff were properly trained, and surveillance was done by continuous remote monitoring systems measuring heart frequency and respiratory rate. So far, only two studies [8,9] have described the clinical course of COVID-19 patients treated with HFNC. Large cohort studies assessing clinical outcomes are missing in this group.…”

Just the Facts: What are the roles of oxygen escalation and noninvasive ventilation in COVID-19?

“…2 This system has demonstrated utility in the management of patients with respiratory distress and COVID-19, with guidelines recommending its use as the firstline strategy for patients with acute hypoxemic respiratory failure, despite conventional oxygen therapy. 1,2,5 Even though high-flow nasal cannula provides flow rates at 40-60 liters per minute, a cough has flow rates approaching 400 liters per minute, and evidence suggests that high-flow nasal cannula is not associated with high risk of viral transmission when appropriately connected. 6,7 If used, the FiO2 should be set at 100% with an initial flow rate set to 20 liters per minute.…”