The common complications of chronic obstructive pulmonary disease mainly include: 1. Chronic respiratory failure: It often occurs during acute exacerbation of chronic obstructive pulmonary disease, with obvious aggravation of cough and shortness of breath, and clinical manifestations of hypoxia and carbon dioxide retention. It is common for patients to have cyanosis of the lips and mouth, or even blurred consciousness, and relevant examinations may suggest hypoxemia and hypercarbia; 2. Spontaneous pneumothorax: the main clinical manifestation is sudden aggravation of dyspnea with obvious cyanosis. The affected side of the chest is percussed with a drum sound, and the breath sounds are diminished or disappeared on auscultation; 3, pulmonary heart disease: pulmonary artery constriction and vascular remodeling caused by reduced pulmonary vascular bed and hypoxia due to pulmonary lesions of chronic obstructive pulmonary disease, resulting in pulmonary hypertension and right ventricular hypertrophy, and eventually right heart failure and right heart insufficiency.