Talk about the mood of sudden fainting

Sudden fainting is caused by many reasons:

First, nerves are common in simple syncope, such as sudden syncope due to compression of jugular sinus, vasodecompression syncope, and sudden syncope in upright position. Abdominal pressure will decrease after urination and emptying, and neuroreflex syncope will occur.

The second is cardiogenic syncope, which is common in arrhythmia, paroxysmal supraventricular tachycardia, rapid atrial fibrillation and bradycardia, including sick sinus node block and myocardial infarction. Some congenital diseases, such as tetralogy of Fallot, can also cause sudden hypoxia and fainting. Head causes include hypertension, arteriosclerosis, cerebral blood supply insufficiency, cerebral hemorrhage, brain injury, etc. Other causes include hyperventilation, hypoglycemia, hyperglycemia and severe anemia.