What causes syncope?

Many people may not have experienced syncope, but they have also seen some people who have syncope. They suddenly faint to the ground and lose self-awareness in a short period of time. Many people think that syncope is related to diseases. Indeed, some diseases can cause syncope. So, what causes syncope? Let’s find out together!

1. Identification of common causes

Nerve-mediated reflex syncope:

(1) Vasovagal syncope: There are often triggers (such as pain, emotion Nervousness, fear, hemophobia, various punctures and minor surgeries, sudden changes in body position, etc.) are more likely to occur in hot weather, dirty air, fatigue, fasting, insomnia and pregnancy;

(2 ) Situational syncope: such as coughing, sneezing, gastrointestinal irritation (swallowing, defecation, abdominal pain), urination, after exercise, after meals or others (such as laughing, operating, weightlifting, etc.);

(3) Carotid sinus syncope: Common triggers include pressing the carotid sinus with hands, turning the head suddenly, too tight a collar, etc.;

(4) Atypical syncope (no obvious triggering factors and/or The behavior is not typical).

Postural hypotensive syncope:

(1) Primary autonomic nervous failure: simple autonomic nervous failure, multiple system atrophy, Parkinson's disease without autonomic abnormality , Lewy body dementia, etc.;

(2) Secondary autonomic nervous system failure: diabetes, amyloidosis, uremia, spinal cord injury, etc.;

(3) Drug-induced Orthostatic hypotension: alcohol, vasodilators, diuretics, phenothiazines, antidepressants, etc.;

(4) Hypovolemia: bleeding, diarrhea, vomiting, etc.

Cardiogenic syncope:

(1) Arrhythmic syncope: ①Bradycardia: such as sinus node dysfunction (including tachycardia syndrome), atrioventricular junction Regional dysfunction, implanted device dysfunction; ② Tachycardia: supraventricular (including atrial fibrillation with pre-excitation syndrome) and ventricular (idiopathic, secondary to organic heart disease); ③ Drug-induced cardiac arrest Bradycardia and tachycardia; ④ Hereditary arrhythmia syndrome (such as long QT syndrome, Brugada syndrome, short QT syndrome, catecholamine-sensitive ventricular tachycardia, etc.);

(2) Organic Syncope due to cardiovascular disease: ① Heart: valvular heart disease, acute myocardial infarction/ischemia, obstructive cardiomyopathy, cardiac tumors (atrial myxoma, tumors, etc.), pericardial disease/cardiac tamponade, congenital coronary artery anomalies, Abnormal artificial valve; ② Others: pulmonary embolism, acute aortic dissection, pulmonary hypertension, cyanotic congenital heart disease;

Cerebral syncope:

Relatively rare, such as severe cerebral artery occlusion , cerebral vasospasm (such as hypertensive encephalopathy), arteritis, aortic arch syndrome, subclavian steal syndrome, basilar artery migraine, etc.;

Others:

Such as Hypoglycemia, hyperventilation, severe anemia, plateau hypoxia, etc.

2. Medical history collection

(1) Clarify the patient's primary disease (the main cause of admission to the neurology department this time).

(2) Premonitory symptoms of syncope or whether there are any triggers.

(3) Characteristics of syncope attacks (speed of occurrence, duration, etc.) and whether there are any sequelae.

(4) Pay attention to accompanying symptoms and signs.

(5) Ask the patient about his past disease history, whether he has the same attack history and family history

(6) Understand the patient’s recent medication status.

3. Physical examination

Vital sign assessment (pay attention to blood pressure and pulse during an attack, and measure lying and standing blood pressure between attacks), focusing on the nervous system, heart and peripheral blood vessels. body.

4. Auxiliary examination

Blood routine, blood sugar, blood biochemistry, liver and kidney function, electrolytes, D-dimer, myocardial enzyme spectrum, electrocardiogram, ambulatory blood pressure, cardiac ultrasound, Carotid and vertebral artery B-ultrasound or neck CTA, cranial MRI and MRA, etc. are selected according to different situations.

5. Treatment principles

(1) Symptomatic treatment: immediately lie on your back or supine with your head down, loosen your collar, and keep your respiratory tract open;

(2 ) Treat the cause;

(3) Avoid triggers, strengthen exercise, and prevent recurrence;

(4) Identify prodromal symptoms early and take certain actions to terminate the attack (such as supine position );

(5) Avoid taking drugs that lower blood pressure;

(6) Consult with relevant departments if necessary.

6. How to deal with sudden syncope

1. If the patient appears pale or gray, yawns frequently, and sweats on the face, neck and hands, this is a sign of brain hypoxia. precursor.

2. If someone complains that he/she is about to faint, he/she should be asked to sit down, loosen the clothes and belt around the neck and waist, and let the head hang to the knees.

3. If the patient has fainted, lift the patient's feet so that the feet are higher than the head to accelerate blood circulation in the brain. The patient usually regains consciousness quickly, but needs to be checked for injuries to the body or head during the fall.

4. The patient can only be given food and drink after he is completely awake, and he can only be given some warm water first. Do not give the patient stimulating drinks such as spirits, because the ingredients in alcohol can reduce Function of physical activity in chronic patients.

5. If the patient's speech after waking up is different from that of ordinary people and he shows strange behavior, he should be sent to the hospital immediately for treatment.