What are the causes of cough syncope?

Generally, cough-induced shock may be caused by a sudden increase in thoracic pressure due to severe coughing, excessive vagal nerve reflex, acute bronchitis, chronic obstructive pulmonary disease (COPD), or cerebral vascular malformations. It is recommended to seek timely medical attention, identify the underlying cause, and receive symptomatic treatment under a doctor's guidance. A detailed analysis is as follows:

1. Sudden increase in thoracic pressure caused by severe coughing: During severe coughing, the intrathoracic pressure rises sharply, impeding venous blood return to the heart, leading to a sudden drop in cardiac output and cerebral ischemia, causing transient shock. This usually resolves after the coughing stops. Sitting or leaning forward while coughing can help reduce thoracic pressure.

2. Excessive vagal nerve reflex: Coughing stimulates the vagus nerve, causing a sudden drop in heart rate and blood vessel dilation, resulting in decreased blood pressure and cerebral hypoperfusion, leading to shock accompanied by dizziness and pallor. Severe coughing should be avoided, and medications such as atropine sulfate tablets, racemic anisodamine tablets, or scopolamine butylbromide capsules may be used as directed by a physician to suppress the vagus nerve. Slow breathing during coughing can reduce nerve stimulation.

3. Acute bronchitis: Bronchial inflammation causes severe coughing, and frequent coughing can trigger fluctuations in thoracic pressure and nerve reflexes, leading to shock accompanied by sputum production and sore throat. Patients may use antibiotics such as amoxicillin-clavulanate potassium tablets, cefuroxime axetil tablets, or ribavirin granules as directed by a physician to treat infection, along with dextromethorphan hydrobromide syrup for cough relief. As the inflammation subsides, the cough improves and the risk of shock decreases.

4. Chronic obstructive pulmonary disease (COPD): Long-term lung damage leads to reduced respiratory function; severe coughing further worsens hypoxia and circulatory impairment, causing shock accompanied by wheezing and chest tightness. Patients should use medications such as salbutamol aerosol, budesonide-formoterol powder inhaler, or cefoperazone sodium and sulbactam sodium injection as directed by a physician to improve breathing and control infection. Long-term home oxygen therapy is recommended, and strenuous activities that may trigger severe coughing should be avoided.

5. Cerebral vascular malformation: Individuals with abnormal cerebral vascular structures may experience sudden blood pressure elevation during severe coughing, leading to disordered blood flow in malformed vessels and interruption of cerebral perfusion, resulting in shock accompanied by headache and limb numbness. Immediate cessation of physical activity is necessary. As directed by a physician, nimodipine tablets or flunarizine hydrochloride capsules may be used to prevent cerebral vasospasm, and dextromethorphan hydrobromide tablets can be taken for cough suppression. If necessary, interventional embolization of the cerebral vessels may be performed to occlude malformed vessels and prevent recurrence.

In daily life, active prevention of respiratory infections is important, along with avoiding irritants such as smoke and dust to reduce triggers of severe coughing. Patients with underlying conditions should undergo regular treatment, carry emergency medications at all times, and bend forward slowly during coughing to reduce thoracic pressure and lower the risk of shock.