Patients with Bronchiectasis experience exacerbations with hypercapnic respiratory failure associated with an increased respiratory workload that may require intensive care unit (ICU) admission due to the inability of the respiratory muscles to compensate for increased demand. These exacerbations are frequently treated with noninvasive ventilation (NIV).

NIV has been shown to unload the respiratory muscles, increase alveolar ventilation and gas exchange and reverse the rapid and shallow breathing pattern commonly adopted by bronchiectasis patients with advanced lung disease.

NIV is a cornerstone therapy for hypercapnic acute respiratory failure. Still, there is also an increasing interest in high-flow nasal cannula (HFNC) as a potential alternative treatment in this indication. HFNC delivers an actively heated and fully humidified gas mixture with flow rates up to 60 L/min and adjustable FiO2 from 21 to 100%. The high flow rates generate small amounts of positive end-expiratory pressure (PEEP) that may help counterbalance the effects of intrinsic PEEP (PEEPi) on the work of breathing and might act by washing out of the physiological dead space. Furthermore, it could help to facilitate secretion clearance from the humidified gas.

Studies have demonstrated the benefits of HFNC in acute hypoxemic respiratory failure, after cardiothoracic surgery, and in preventing post-extubation failure among unselected cohorts of critically ill patients during weaning from invasive mechanical ventilation.

However, the current evidence of using HFNC in patients with hypercapnic acute respiratory failure is limited. We aime to spotlight this research area.

Inclusion Criteria:

• Patients will be eligible for enrolment if diagnosed with bronchiectasis and admitted to the respiratory intensive care unit (RICU), requiring ventilator support without invasive mechanical ventilation.

Exclusion Criteria:

• Age: less than 18 years. Patients with post-arrest encephalopathy. Patient with the previous tracheotomy. Patients who received invasive ventilatory support. Patients with end-organ failure.

Patients will be eligible for enrolment if diagnosed with bronchiectasis and admitted to the respiratory intensive care unit (RICU), requiring ventilator support without invasive mechanical ventilation.