The most serious postoperative complications are respiratory distress and asphyxia after thyroid surgery, which can often endanger patients’ lives if they are not rescued in time or handled decisively. The most common cause of postoperative dyspnea and asphyxia is post-thyroidal hemorrhage, which occurs within 24 hours after surgery. Common causes of bleeding: (1) Hemorrhage due to dislodgement of the superior and inferior thyroid vascular ligatures. (2) Severe bleeding from the residual surface of the gland after partial or subtotal thyroidectomy. (3) Dislodgement of the ligature at the laryngeal entry of the laryngeal nerve or reopening of a small vessel that was hemostatic by electrocoagulation. (4) Poor local drainage leading to blood accumulation. (5) Bleeding from the broken end of the strap muscle. (6) Bleeding from the anterior jugular vein, anterior jugular vein arch or under the skin flap. (2) Unskilled tracheal intubation technique by the anesthesiologist, rough intubation or repeated multiple intubations, resulting in traumatic edema of the patient’s larynx. 3, tracheal softening: long-term compression of the thyroid mass can lead to tracheal softening and collapse. 4, tracheospasm: when operating close to the trachea during surgery, the trachea can be strongly stimulated due to rough movements, which can induce tracheospasm and lead to airway obstruction. 5. Bilateral laryngeal nerve injury: Bilateral laryngeal nerve injury during thyroid surgery or thyroid cancer invading bilateral laryngeal nerves. 6.Side effects of drugs: When beta-blockers are used in hyperthyroidism or combined with heart disease, especially in patients with bronchial asthma or increased sympathetic excitability, beta-blockers may induce bronchial smooth muscle spasm and cause airway obstruction due to competition for adrenergic beta receptors and antagonism to the tracheal diastolic effect of catecholamines. 7.Postoperative complications of pulmonary infection and respiratory distress. 8. Long-term discontinuation of thyroxine tablets after near-total thyroidectomy for thyroid cancer may also induce respiratory distress. Preventive measures 1. Pre-operative comprehensive medical history should be taken to find out whether there are any contraindications to the application of insulin and other respiratory diseases; any inflammatory diseases of the respiratory system should be treated and controlled; find out whether the patient has a history of asthma and triggering factors. 2.Preoperative CT examination should be routinely performed for patients with large thyroid masses and long duration of disease to understand the tracheal pressure, and to fully assess the risk of anesthesia and the need for prophylactic tracheotomy before surgery. Preoperative vocal cord examination should be routinely performed. If one side of the vocal cord is found to be abnormal or paralyzed before surgery, great importance should be attached to the protection of the normal side of the recurrent laryngeal nerve during surgery. 4. Intraoperative emphasis should be placed on complete hemostasis, and all important vessels should be firmly ligated. 5.The cervical trauma should be compressed during anesthetic extubation to avoid bleeding induced by the severe cough caused by the extubation action. Solution steps and techniques 1. Be gentle during anesthesia intubation and surgery to avoid excessive trauma resulting in laryngeal edema, which generally improves after postoperative oxygenation and hormone application. 2, postoperative bleeding of the thyroid gland is in the closed gap of the deep cervical fascia, and a larger amount of accumulated blood (>100ml) can directly compress the trachea leading to asphyxia. If the above situation occurs, you should make a quick judgment, remove the sutures in time, open the incision, remove the hematoma, and release the compression on the trachea. If the patient’s respiratory function still does not improve, tracheotomy should be performed immediately. 3.Patients with softened or obviously collapsed trachea can be given tracheal suspension or prophylactic tracheotomy, or preoperative tracheal stents can be placed. 4.Injury to bilateral recurrent laryngeal nerve during thyroidectomy or invasion of bilateral recurrent laryngeal nerve by thyroid cancer may lead to acute respiratory obstruction due to paralysis of both vocal cords, so prophylactic tracheotomy must be performed; patients whose thyroid cancer has invaded unilateral recurrent laryngeal nerve and whose contralateral recurrent laryngeal nerve has been surgically exposed intact may not undergo tracheotomy for the time being, but hormones should be applied routinely during and after surgery to relieve laryngeal edema and to prepare for emergency tracheotomy. Preparation. Postoperative observation points A sterile tracheotomy kit and gloves should be routinely placed at the patient’s bedside for emergency use after surgery. Postoperative medical staff should regularly inspect the ward and pay attention to the changes in breathing, swelling and drainage of the patient’s incision, and strengthen postoperative observation is the key to early diagnosis and timely treatment.