● | PaO2< 7.3 KPa (55 mmHg, SaO2< 88%) in stable phase and during optimal therapeutic regime |
● | PaO2 between 7.3 and 7.8 kPa (55-59 mmHg, SaO2< 89%) in the presence of pulmonary hypertension, pulmonary heart, declivity edema, erythrocytosis (hematocrit > 55%), cognitive deficit |
● | Patients with manifest hypoxemia during exercise or at night |