Key research recommendations
| 1. Should HFNC or COT be used in patients with acute hypoxaemic respiratory failure? | More evidence is needed to identify patients at high risk of deterioration and therefore more likely to benefit from HFNC. Which treatment (HFNC or COT) results in aerosolisation of infectious particles in COVID-19, and what are the clinical implications of this? |
| 2. Should HFNC or NIV be used in patients with acute hypoxaemic respiratory failure? | More evidence is needed to assess the impact of HFNC versus NIV in COVID-19 and other viral illnesses, as well as in patients at different risk of induced lung injury and different PaO2/FiO2 ratio severity. More evidence is needed regarding effectiveness of HFNC versus NIV in both helmet and facemask forms. Which treatment (HFNC or COT) results in aerosolisation of infectious particles in COVID-19, and what are the clinical implications of this? |
| 3. Should HFNC or COT be used during breaks from NIV in patients with acute hypoxaemic respiratory failure? | More evidence is needed to identify patients who are likely to benefit from HFNC during breaks from NIV (hypoxic and hypercapnic populations). |
| 4. Should HFNC or COT be used in post-operative patients after extubation? | More evidence is needed to identify which patients (type of surgery, comorbidities, PaO2/FiO2 level) are most likely to benefit from HFNC over COT when used post-operatively according to different settings (high- versus low-intensity monitoring); however, it is likely that any such effects in low-risk groups will be small. |
| 5. Should HFNC or NIV be used in post-operative patients after extubation? | Further large RCTs are needed to compare NIV and HFNC in different subgroups of surgical patients according to different settings (high- versus low-intensity monitoring). Additional research is needed to identify the subgroups of post-operative patients at high risk of respiratory failure most likely to benefit from use of combination treatment (NIV plus HFNC) versus NIV alone. |
| 6. Should HFNC or COT be used in nonsurgical patients after extubation? | More evidence is needed to identify which patients (underlying disease, comorbidities, PaO2/FiO2 level) according to different settings (high- versus low-intensity monitoring) are most likely to benefit from post extubation HFNC over COT. |
| 7. Should HFNC or NIV be used in nonsurgical patients after extubation? | More evidence is needed to identify which patients (underlying disease, comorbidities, PaO2/FiO2 level) according to different settings (high- versus low-intensity monitoring) are most likely to benefit from post-extubation HFNC over COT are most likely to benefit from NIV over HFNC. |
| 8. Should HFNC or NIV be used in patients with acute hypercapnic respiratory failure? | More randomised data are required to determine populations where HFNC can be a first-line alternative to NIV (e.g. severity of COPD; patients with hypercapnic failure from causes other than COPD; hypersecretion, poor mask tolerance, agitation). More evidence needed to predict which patients are likely to successfully transition to HFNC from NIV. |
HFNC: high-flow nasal cannula; COT: conventional oxygen therapy; NIV: noninvasive ventilation; COVID-19: coronavirus disease 2019; PaO2: arterial oxygen partial pressure; FiO2: inspiratory oxygen fraction; RCT: randomised controlled trial.