Oxygen Therapy Management in COVID-19 Patients
Initial Oxygenation Strategy
- The American Thoracic Society suggests starting oxygen therapy if the SpO2 is < 92%, and imperatively if the SpO2 is < 90% 1
- Maintaining the SpO2 between 90-96%, without exceeding 96% to avoid hyperoxia, is recommended by the European Respiratory Society 1, 2
- Close monitoring of vital signs, respiratory status, and changes in the oxygenation index is advised by the Military Medical Research 2, 3
Progression to High-Flow Nasal Cannula (HFNC) Oxygen Therapy
- The European Respiratory Society recommends using HFNC if conventional oxygen therapy via standard nasal cannula is insufficient 4, 5, 6
- HFNC delivers a high flow of humidified and heated gas (30-60 L/min) with controlled oxygen concentration, as stated by the European Respiratory Journal 4, 5
- HFNC has shown a reduction in 90-day mortality and an increase in the number of ventilator-free days compared to standard oxygen therapy, according to the European Respiratory Journal 4, 5
Indications for Therapeutic Escalation
- If there is no improvement or deterioration in the patient's condition or oxygenation index ≤ 150 mmHg within a short period (1-2h) under HFNC or non-invasive ventilation, rapid intubation and invasive mechanical ventilation should be performed, as recommended by the Military Medical Research 2, 3
- The European Respiratory Society advises not to delay mechanical ventilation in patients who do not respond to treatment 4, 5
Important Precautions
- HFNC and CPAP are classified as aerosol-generating procedures and should be administered in a secure environment with personnel wearing appropriate personal protective equipment, as stated by the European Respiratory Journal 4, 5
- Limiting the oxygen flow to the minimum necessary (preferably < 5 L/min) to maintain arterial oxygen saturation and reduce the risk of aerosolization is recommended by the Anaesthesia journal 8
- For patients requiring invasive mechanical ventilation, a lung-protective ventilation strategy should be adopted: low tidal volume (4-6 ml/kg) and low plateau pressure (< 30 cmH2O), as advised by the Military Medical Research 2, 3