The purpose of sputum aspiration is mainly to remove the sputum from the patient’s airway, keep the airway unobstructed, and prevent the obstruction of the airway leading to sputum asphyxia, and it is generally used for patients in critical condition, coma and other patients with poor ability to excrete sputum on their own, and sputum can be aspirated through the mouth and nose, tracheal intubation, and tracheotomy, but improper operation of sputum aspiration can also stimulate the airway, lead to airway spasm, induce or aggravate respiratory distress, and make the patient’s oxygen saturation drop; because of the The negative pressure during aspiration may also damage the respiratory mucosa, leading to bleeding and inducing infection; it may also lead to cardiac arrhythmias, such as paroxysmal atrial tachycardia and ventricular prematureness, which may endanger patients’ lives. In aspiration, pay attention to effective aspiration and on-demand aspiration, don’t be too frequent, generally need to interval 1-2 hours, adjust the number of aspiration according to the sputum volume and sputum excretion of the patient, stimulate the throat as much as possible, make the patient cough up the deep sputum, in order to reduce the airway damage caused by too deep aspiration.