A rapid decrease in pulmonary arterial pressure by noninvasive positive pressure ventilation in a patient with chronic obstructive pulmonary disease

The natural history of chronic obstructive pulmonary disease (COPD) is characterized by progressive decrements in expiratory airflow, increments in end-expired pulmonary volume, hypoxaemia, hypercapnia and the progression of pulmonary arterial hypertension (PAH). Noninvasive positive pressure ventilation (NPPV) treatment is increasingly used for the treatment of acute and chronic respiratory failure in patients with COPD. NPPV can increase PaO 2 and decrease PaCO2 by correcting the gas exchange in such patients. The acute effect of NPPV on decreasing PAP is seen in patients with respiratory failure, probably due to the effect on cardiac output. Here, a case with COPD whose respiratory acidosis and PAH rapidly improved by NPPV was presented and therefore we suggested to perform an echocardiographic assessment to reveal an improvement of PAH as well as respiratory acidosis, hypercapnia and hypoxemia with that treatment.