High flow nasal oxygen therapy to avoid invasive mechanical ventilation in SARS-CoV-2 pneumonia: a retrospective study

Abstract

Background The efficacy of high flow nasal canula oxygen therapy (HFNO) to prevent invasive mechanical ventilation (IMV) is not well established in severe coronavirus disease 2019 (COVID-19). The aim of this study was to compare the risk of IMV between two strategies of oxygenation (conventional oxygenation and HFNO) in critically ill COVID 19 patients. Methods This was a bicenter retrospective study which took place in two intensive care units (ICU) of tertiary hospitals in the Paris region from March 11, to May 3, 2020. We enrolled consecutive patients hospitalized for COVID-19 and acute respiratory failure (ARF) who did not receive IMV at ICU admission. The primary outcome was the rate of IMV after ICU admission. Secondary outcomes were death at day 28 and day 60, length of ICU stay and ventilator-free days at day 28. Data from the HFNO group were compared with those from the standard oxygen therapy (SOT) group using weighted propensity score. Results Among 138 patients who met the inclusion criteria, 62 (45%) were treated with SOT alone, and 76 (55%) with HFNO. In HFNO group, 39/76 (51%) patients received IMV and 46/62 (74%) in SOT group (OR 0.37 [95% CI, 0.18–0.76] p = 0.007). After weighted propensity score, HFNO was still associated with a lower rate of IMV (OR 0.31 [95% CI, 0.14–0.66] p = 0.002). Length of ICU stay and mortality at day 28 and day 60 did not significantly differ between HFNO and SOT groups after weighted propensity score. Ventilator-free days at days 28 was higher in HNFO group (21 days vs 10 days, p = 0.005). In the HFNO group, predictive factors associated with IMV were SAPS2 score (OR 1.13 [95%CI, 1.06–1.20] p = 0.0002) and ROX index > 4.88 (OR 0.23 [95%CI, 0.008–0.64] p = 0.006). Conclusions High flow nasal canula oxygen for ARF due to COVID-19 is associated with a lower rate of invasive mechanical ventilation.

Evaluation of the ROX index in SARS-CoV-2 Acute Respiratory failure treated with both High-Flow Nasal Oxygen (HFNO) and Continuous Positive Airway Pressure (CPAP)

“…We document improved mortality with HFNO compared with face mask CPAP like numerous others 10,13,14,21,26,27 . The ranges of measurements for the ROX were similar for HFNO and CPAP in SARS-CoV-2 ARF.…”

“…A benchmark for success of non-invasive respiratory support will enable easier comparison but has yet to emerge 24,25 . The ROX index, a ratio of oxygenation and respiratory rate, has been validated in SARS-CoV-2 for HFNO 10,11,13,14,26 . It’ s use in CPAP is reported in small studies with conflicting results 11,27 .…”

Similar Rates of AKI during the First Two Waves of COVID-19 in Northern Italy: a single-center study

“…During the second wave, we noted a minor rate of ICU admissions and mechanical ventilation; conversely, this tendency was balanced by a compensative increase in non-invasive ventilation such as high-flow nasal oxygen (HFNO) and non-invasive ventilation (NIV), reflecting the prevalent opinions of that period of postponing invasive ventilation. [19,20] According to the insights on the inflammatory pathway in COVID-19 [21][22][23][24], a higher number of patients were treated with steroids during the wave-2, but the beneficial effects of steroids and immunomodulators in the prevention and mitigation of AKI remained unproved in our study. AKI was associated with classical risk factors such as diuretic and cardiovascular disease, suggesting dehydration or hemodynamic instability as a predisposing condition for kidney injury.…”

Cardiopulmonary Pathophysiological Aspects in the Context of COVID-19 and Obesity

“…Identifying excessive respiratory effort is essential to adapt supportive oxygen therapy. High-flow nasal cannulas can be used as first-line therapy in patients with respiratory insufficiency since they may prevent invasive intubation [ 78 ]. Severe patients with obstructive sleep apnea and chronic obstructive pulmonary disease may benefit from noninvasive positive pressure ventilation [ 79 ].…”