Noninvasive respiratory support for acute respiratory failure due to COVID-19

Purpose of review Noninvasive respiratory support has been widely applied during the COVID-19 pandemic. We provide a narrative review on the benefits and possible harms of noninvasive respiratory support for COVID-19 respiratory failure. Recent findings Maintenance of spontaneous breathing by means of noninvasive respiratory support in hypoxemic patients with vigorous spontaneous effort carries the risk of patient self-induced lung injury: the benefit of averting intubation in successful patients should be balanced with the harms of a worse outcome in patients who are intubated after failing a trial of noninvasive support. The risk of noninvasive treatment failure is greater in patients with the most severe oxygenation impairment (PaO2/FiO(2) < 200 mmHg). High-flow nasal oxygen (HFNO) is the most widely applied intervention in COVID-19 patients with hypoxemic respiratory failure. Also, noninvasive ventilation (NIV) and continuous positive airway pressure delivered with different interfaces have been used with variable success rates. A single randomized trial showed lower need for intubation in patients receiving helmet NIV with specific settings, compared to HFNO alone. Prone positioning is recommended for moderate-to-severe acute respiratory distress syndrome patients on invasive ventilation. Awake prone position has been frequently applied in COVID-19 patients: one randomized trial showed improved oxygenation and lower intubation rate in patients receiving 6-h sessions of awake prone positioning, as compared to conventional management. Noninvasive respiratory support and awake prone position are tools possibly capable of averting endotracheal intubation in COVID-19 patients; carefully monitoring during any treatment is warranted to avoid delays in endotracheal intubation, especially in patients with PaO2/FiO(2) < 200 mmHg.

Automated summary

This narrative review discusses the benefits and possible harms of noninvasive respiratory support for COVID-19 respiratory failure. Maintaining spontaneous breathing in hypoxemic patients with vigorous effort carries the risk of patient self-induced lung injury. The risk of noninvasive treatment failure is higher in patients with severe oxygenation impairment. High-flow nasal oxygen (HFNO) is the most widely applied intervention, but noninvasive ventilation (NIV) and continuous positive airway pressure (CPAP) with different interfaces have also been used with varying success rates. Prone positioning and awake prone position have shown potential in avoiding endotracheal intubation, but careful monitoring is necessary, especially in patients with severe hypoxemia.