Tracheostomy is often performed in patients after or anticipated prolonged mechanical ventilation, who are usually required oxygen therapy after discontinuation of mechanical ventilation.

Tracheostomy is often performed in patients after or anticipated prolonged mechanical ventilation, who are usually required oxygen therapy after discontinuation of mechanical ventilation.The high-flow tracheal (HFT) oxygen therapy in tracheostomized patients has been shown that can improve oxygenation,but can not induce positive end-expiratory pressure and elevation of end-expiratory lung volume. A modified HFT system by increasing expiratory resistance might induce PEEP and consequently elevate EELV.

Inclusion Criteria:

• The tracheostomized patient requiring the convenient oxygen therapy.

Exclusion Criteria:

• Under 18 years;
• history of esophageal, gastric or lung surgery;
• The contraindication of using EIT (pacemaker, defibrillator, and implantable pumps).

The tracheostomized patient