PULMONARY-HYPERTENSION DURING SLEEP

During sleep patients with chronic obstructive lung disease develop - especially during REM-sleep - hypoxemic episodes with an increase of pulmonary artery pressure. The increase of the pulmonary artery pressure is dependant on the degree of O2-desaturation. The meaning of an increase in the lesser circulation concerning life-expectancy is still unclear. The pulmonary artery mean pressure can be lowered by continuous application of oxygen. The peaks can also be eliminated. In patients with sleep-apnea syndrome O2-desaturations can also be found. They are paralleled by an increase of the pulmonary artery pressure. There is still the question of cyclical variations of the pulmonary artery pressure may lead to a cor pulmonale. Pulmonary hypertension in patients with sleep-apnea syndrome is perhaps due to a reduced chemosensitivity and to an associated ventilatory disturbance.