High flow nasal cannula oxygen therapy has been widely used in critically ill patients. Despite effectiveness of high flow nasal cannula as a treatment, optimal methods to withdrawal high flow nasal cannula after recovery from preexisting conditions has not been investigated to date. In this study, we will evaluate the efficacy and safety of three different weaning methods in patients with high flow nasal cannula oxygen therapy.

Comparison of three weaning strategies: flow reduction first versus fraction of inspired oxygen (FiO2) first versus simultaneous reduction

Inclusion Criteria:

• The patients applying high flow nasal cannula and satisfying the following weaning criteria.

  1. Patient who has recovered from the underlying condition
  2. No signs of respiratory distress like agitation, diaphoresis or anxiety
  3. Arterial pH ≥ 7.35, SpO2 > 90% on FiO2 ≤ 0.5
  4. Respiratory rate ≤ 25/min, Heart rate ≤120/min, Systolic blood pressure ≥ 90mmHg

Exclusion Criteria:

• Severe hypercapnia (pH <7.25)
• Respiratory arrest requiring tracheal intubation
• Cardiac arrest, acute coronary syndrome or life threatening arrhythmias
• Failure of more than two organs
• Recent trauma or burns of the neck and face
• Non- cooperation
• Pregnancy
• Refusal of treatment