Inclusion Criteria:  Newly admitted prolonged mechanical ventilation patients on tracheostomy tube ventilation (over 21 days, a minimum of 6 hours a day); Over 18 years of age; PEEP below 8 cm H2O; FiO2 below 60%;  Hemodynamically stable:  Alert and oriented (does not apply to patients in a vegetative state); Blood pressure at or above 80/50 mmHg; Body temperature - normal around 36.6°C; Heart rate - 40-140 beats per minute; Breath - 10-20 breaths per minute; No active infection (clinically stable patients receiving antibiotic treatment for more than 48 hours following an acute infection may be enrolled in the trial);  Exclusion Criteria:  Ventilated patients with PEEP values exceeding 8 cmH2O, which mandates the use of FiO2 values over 60%;  Hemodynamically unstable patients:  Blood pressure below 80/50 mmHg; Over 140 beats per minute, or less than 40 beats per minute in symptomatic patients; Newly diagnosed fever (over 38.0°C); Patients receiving antibiotics for an active infection, under 48 hours. Blood pH values below 7.3 due to metabolic abnormality; Patients with irreversible advanced musculoskeletal neurodegenerative disorders.