Background Coronary heart disease (CHD) with COPD patients through the establishment of artificial airway,mechanical ventilation can maintain efficient gas exchange,correct the lack of oxygen and carbon dioxide retention,thus improving respiratory function and cardiac function.Strengthen artificial airway in patients with mechanical ventilation of wetting of nursing is to keep respiratory tract unobstructed,essential to the effective measures to prevent and reduce complications,in our study we will discuss CHD with COPD patients with mechanical ventilation of double humidifier wet airway care methods and the impact on patients sputum.