sudden death (in medicine, sporting competitions etc)



Overview

Sudden death can be preceded by chest pain, dyspnea, blackouts, dizziness, etc. About 90% of sudden cardiac deaths are cardiac arrests, while the rest are caused by other major acute illnesses. Patients with a family history of sudden death have a higher rate of sudden death.

What is Sudden Death?

Definition

Sudden death is defined by the World Health Organization as “the sudden death of a normally healthy or seemingly healthy person from a natural cause within an unexpectedly short period of time”.

Sudden death consists of three elements:

Already dead: Sudden death is a terminal diagnosis, a disease that can only be prevented, not treated.

Death due to disease: death due to all external factors are not considered sudden death, such as drowning, car accidents and poisoning.

Unforeseen, sudden death: the patient died without signs, no one predicted the upcoming attack of the disease. Death due to terminal illness is not considered sudden death.

Classification

Sudden death is categorized according to the time of death

Instantaneous death: death occurs within minutes of the onset of the disease.

Very sudden death: within 1 hour of the onset of the disease.

Sudden death: within 24 hours of the onset of the disease.

Non-sudden death: Death occurs 24 hours after the onset of the disease.

Sudden death by cause

Sudden cardiac death: The most common cause is coronary artery disease, followed by organic heart disease (abnormalities in the shape and structure of the heart) and myocardial ion channel defective diseases.

Non-cardiac sudden death: including pulmonary infarction, bronchial asthma, cerebral hemorrhage, acute hemorrhagic necrotizing pancreatitis, aortic coarctation, and endogenous hyperkalemia.

Morbidity

Data from the American Heart Association in 2015 showed that the survival rate for out-of-hospital cardiac arrest was only 10.6%, some of which had neurologic damage, with a higher incidence in men than in women.

Sudden cardiac death, i.e., deaths due to heart disease, account for about 90% of deaths; non-cardiac sudden death, i.e., deaths due to other causes, account for about 20%.

The age distribution of sudden cardiac death is bimodal, i.e., the first peak occurs in the first 6 months of life (called sudden infant death syndrome), and the second peak mostly occurs between the ages of 45 and 75, which coincides with the age distribution of coronary heart disease.

The temporal distribution of sudden death shows a clear biological rhythm, i.e., between 6:00 a.m. and 12:00 p.m. is the time of high incidence of sudden death.

The risk of sudden death is higher in people with a family history than in the general population.

Questions you may have

What are the precursors to sudden death?

Some of the symptoms that can be felt before sudden death are listed below:

A few hours to a few days before the onset of the illness, some patients may feel symptoms such as tightness in the chest, shortness of breath, fatigue, and palpitations.

During an attack of the disease, symptoms such as severe chest pain, difficulty in breathing, sudden panic, and persistent dizziness may occur.

If you experience any of these symptoms, you must go to the emergency department of the hospital immediately for prompt treatment.

Who is prone to sudden death?

Patients with coronary heart disease: This is the highest risk factor for sudden death, and many patients have heart disease before sudden death.

Patients with “three highs”: high blood pressure and high blood lipids, diabetes, there is a potential risk of sudden cardiac death.

Unhealthy dietary habits: too much high-fat, high-protein food, such as animal meat, can lead to obesity, hyperlipidemia or hypertension.

Attention should be paid to prevention in daily life by actively treating underlying diseases and establishing healthy living habits to reduce the risk of sudden death.

Can sudden death be prevented?

Sudden death can be prevented in the following ways:

Regular medical checkups: Regular medical checkups can detect hidden diseases that may lead to sudden death.

Active treatment of underlying diseases: If heart disease or other diseases that may cause sudden death are already present, they should be treated as soon as possible.

Lifestyle modification: Stop smoking and limit alcohol consumption, exercise regularly and eat a healthy diet.

Causes

Causes

There are many causes of sudden death, which are broadly categorized into two types: one is due to problems with the heart itself, called sudden cardiac death, which accounts for about 90% of sudden deaths; the other is due to other causes, called non-cardiac sudden death, which accounts for about 20% of sudden deaths.

Sudden cardiac death

Organic heart disease

Diseases such as coronary artery disease, acute coronary syndrome, ischemic cardiomyopathy, various valvular diseases, acute severe myocarditis, and acute pulmonary embolism can lead to sudden cardiac death.

Ion channel diseases or abnormal myocardial electrical activity

Such as Brugada syndrome, long QT or short QT syndrome, ventricular tachycardia with short intervals, catecholamine-sensitive ventricular tachycardia, preexcitation combined with atrial fibrillation, and severe bradyarrhythmia.

Others

Severe electrolyte or acid-base balance disorders, severe myocardial ischemia or exacerbation of heart failure, severe stress or mood swings may induce malignant arrhythmias leading to sudden cardiac death.

Non-cardiac sudden death

The causes of non-cardiac sudden death are more varied and mainly include:

Respiratory diseases such as pulmonary embolism and bronchial asthma.

Neurologic diseases of the acute cerebrovascular disease, such as cerebral hemorrhage.

Digestive system diseases, such as acute hemorrhagic necrotizing pancreatitis.

Aortic coarctation aneurysm.

Severe electrolyte disorders, such as endogenous hyperkalemia or hypokalemia.

Pathogenesis

Sudden cardiac death

Sudden cardiac arrest is caused by malignant arrhythmia such as ventricular tachycardia, ventricular fibrillation, cardiac arrest, etc., resulting in the heart’s inability to pump normally, the effective blood circulation stops, and the organs of the body suffer from a lack of blood supply and oxygenation, with severe acidosis and lactic acid accumulation.

If it cannot be corrected in time to restore the effective contraction of the heart, the patient will die soon.

Non-cardiac sudden death

Sudden non-cardiac death, regardless of the cause, is the result of severe dysfunction of vital organs such as the heart, brain and lungs. A sharp stimulus causes the organs to suddenly terminate their activity, directly resulting in death.

Risk factors

Emotional arousal

Emotional excitement may induce coronary artery spasm, leading to acute myocardial ischemia and malignant arrhythmia, triggering sudden death.

Extreme emotional changes (e.g., sudden excitement, agitation, anger, etc.) and mental stimulation in daily life may lead to sudden death.

Excessive physical activity

Under normal circumstances, moderate exercise in patients with coronary heart disease can prevent sudden death, but strenuous exercise may trigger sudden cardiac death.

In adults, 11% to 17% of cardiac arrests occur during or immediately after strenuous exercise and are associated with the occurrence of ventricular fibrillation.

The risk of sudden death is elevated during strenuous exercise in people who do not exercise regularly.

Unhealthy lifestyle and mental factors

Smoking, drinking alcohol, staying up late, and lack of exercise are poor lifestyle habits that can easily lead to adverse effects on the cardiovascular system.

Emotional depression caused by excessive mental stress, loneliness and overburdened life is also closely related to the occurrence of sudden death.

Disease factors

Common cardiovascular disease risk factors such as hypertension, hyperlipidemia and diabetes are also risk factors for sudden death.

If you have one or more of the above risk factors, you should actively communicate with your doctor, strengthen medical checkups, and adjust your lifestyle to reduce the probability of sudden death.

Symptoms

Early Warning Symptoms

Many sudden deaths occur without warning symptoms, with sudden cardiac arrest and loss of consciousness. In some cases, some patients may experience symptoms that signal the onset of sudden death, which are called “warning symptoms”.

A few hours to a few days before the onset of the disease, some patients may feel symptoms such as tightness in the chest, shortness of breath, fatigue, and palpitations.

During an attack, before the heart stops, there may be severe chest pain, rapidly increasing breathlessness, sudden panic attacks, blackouts, and persistent dizziness.

Patients who are undergoing strenuous exercise may experience nausea, vomiting, and dizziness.

Main Symptoms

Blood stops circulating immediately after sudden death occurs, and the patient will experience a series of symptoms such as loss of consciousness, dilated pupils, loss of arterial pulsation, and respiratory arrest.

Medical treatment

Department of Medicine

Emergency Department

If you experience sudden onset of severe chest pain, difficulty breathing, panic, blackness, dizziness, etc., it is recommended that you call “120” or go to the hospital immediately, or ask someone close to you for help if you are not alone.

Preparation for medical treatment

Preparing for medical treatment: registration, preparation of documents, and common problems.

Tips for seeking medical treatment

If you find someone around you who has lost consciousness, stopped breathing, or whose heart has stopped, call the emergency number immediately.

Perform CPR immediately.

If there is an AED (Automated External Defibrillator) in the vicinity, rapid defibrillation can be performed.

Medical Preparation Checklist

Symptom Checklist

Particular attention needs to be paid to the time of symptom onset, special manifestations, etc.

Did the patient feel any discomfort such as chest tightness, shortness of breath, palpitations, etc. before he/she fell unconscious?

Medical history checklist

What was the patient doing at the onset of illness, before the onset of illness, and whether he/she was eating?

Has there been any recent late night, work stress, emotional excitement, strenuous exercise, etc.?

Is there any hypertension, dyslipidemia, diabetes mellitus, and coronary heart disease, and do relatives have these diseases?

Does the patient have smoking and drinking habits?

Are there any other diseases in the past?

Diagnosis

Diagnostic basis

Physical examination: The doctor will quickly perform a physical examination to check for signs such as loss of consciousness, pulse arrest, respiratory arrest, and loss of heart sounds.

Electrocardiogram: Electrocardiogram (ECG) monitoring can be used to see if the patient has an arrhythmia that requires defibrillation, or to determine from the ECG if the patient is dead. If the ECG suggests cardiac arrest, no further defibrillation is necessary.

Differential Diagnosis

Sometimes syncope caused by other illnesses can be mistaken for sudden death by bystanders. A simple diagnosis can be made by palpating the carotid artery to determine if there is a pulse or by checking the chest to see if there is a rise and fall.

If respiration and carotid artery pulsation are present, it is possible that the fainting was caused by poisoning or hypoglycemia, and you can call the emergency number for help.

If there is no chest rise and fall, but there is carotid artery pulsation, it may be apnea, make sure there is no foreign body in the patient’s mouth, if necessary, remove it as soon as possible, and call the emergency number for help.

Treatment

Principles of treatment

Principle of out-of-hospital treatment: The probability of resuscitation is very low when the precursor of sudden death occurs outside the hospital, and foreign data show that it is only about 10%. If there are witnesses to give CPR, AED treatment and other rescue measures in a timely manner, it is possible to save the patient’s life.

Principles of in-hospital treatment: In-hospital treatment is not only limited to cardio-cerebral and pulmonary resuscitation, but also advanced life support, correction of internal environment disorders, prevention and treatment of complications and other aspects of life-saving, reducing disability and improving the quality of survival.

Treatment Methods

Out-of-hospital treatment

70.0% to 87.8% of sudden deaths occur outside the hospital, such as at home and in public places.

People with a history of heart disease who are unwell should remain calm, do not walk around, call the emergency number and then take a prone, semi-prone or sitting position to rest, and those with no contraindications can take nitroglycerin under the tongue immediately.

If someone close to you shows signs of sudden death, you should help him or her to call the emergency number and make sure whether there is an AED or professional first-aiders around to prepare for first aid.

If the patient experiences loss of consciousness, respiratory arrest, or cardiac arrest, CPR should be performed immediately: undo clothing and perform 30 chest compressions and 2 artificial respirations alternately until the patient is revived.

If an AED is available at the scene, it should be fetched immediately and used according to the instructions.

Refresh

In-hospital treatment

In-hospital resuscitation involves close multidisciplinary collaboration under the unified direction of an experienced physician.

First Aid Measures

In the event of cardiac arrest, physicians will quickly perform cardiopulmonary resuscitation (CPR) and electrical defibrillation to help restore the patient’s voluntary heartbeat.

Advanced Cardiovascular Life Support

Advanced Cardiovascular Life Support (ACLS) is performed by specialized emergency medical personnel.

Mechanically Assisted Ventilation: i.e. the use of a ventilator to assist breathing.

Circulatory assist devices: external counterpulsation, temporary or permanent cardiac pacing, etc.

Drug resuscitation: application of cardiac drugs such as cediran, antiarrhythmic drugs such as verapamil, amiodarone, etc., vasoactive drugs such as epinephrine, isoprenaline, etc..

Intravenous fluids, correct acid-base balance disorders, etc., such as according to blood gas analysis, timely application of alkaline fluid sodium bicarbonate to correct acidosis.

Correcting the cause of sudden death

Doctors will quickly get to know the patient’s medical history, conduct physical examination and laboratory tests, etc., to clarify the cause of the patient’s illness through the history and examination results, correct the cause of sudden death, and at the same time, keep the airway open to avoid recurrence of cardiac arrest.

Managing coronary artery problems

If the patient has coronary ischemic heart disease, problems with the coronary arteries need to be dealt with as soon as possible after the return of spontaneous heartbeat. If ST-segment elevation is present, pharmacologic reperfusion or emergency coronary catheterization may be performed.

Mitigation of brain damage

Prompt rehydration therapy should be administered to keep blood pressure stable, and dehydration should be used as appropriate to reduce cerebral edema and avoid brain damage due to cerebral ischemia. Positive inotropic and vasopressor drugs (e.g. vasopressin and epinephrine) can be used, and subcold therapy can be administered to protect brain tissue.

Other

If there is a secondary acid-base balance imbalance, electrolyte disturbances, or other complications, they need to be corrected promptly. Possible complications include bronchospasm, airway obstruction, gastrointestinal bleeding, and tension pneumothorax.

Treatment of survivors

An electrocardiogram, chest X-ray, echocardiogram, electrolyte and myocardial markers, and invasive blood pressure monitoring should be performed as soon as possible and as soon as possible after resuscitation.

Assess for neurologic damage.

Patients with possible recurrent arrhythmias require subcutaneous implantation of a cardioverter-defibrillator.

Prognosis

Cure

Sudden death is sudden in onset, often lacking prompt assistance at the time of onset, and is rapidly fatal. Cardiac arrest lasting more than 4 to 6 minutes results in irreversible cell death in the brain, followed by biological death in the next few minutes, at which point survival is virtually impossible.

Currently, the survival rate of sudden death is extremely low, reported to be about 10.6% in foreign countries, and the survival rate of sudden death in China is only 1% to 4%.

The survival rate of sudden death in China is only 1% to 4%. Early administration of effective AED or cardiopulmonary resuscitation (CPR) can effectively improve the survival rate of sudden death.

Hazard

Death in a short period of time.

Some of the patients who are saved back will also suffer from ischemic and hypoxic cerebral nerve damage, such as vegetative survival (vegetative) and cerebral dysfunction.

Daily

Daily management

Sudden death does not usually involve daily management outside the hospital; survivors may be managed on a daily basis according to the primary condition that caused the sudden death.

Prevention

There are no signs before the onset of sudden death and the consequences caused by the onset of the disease are serious. Therefore, attention should be paid to prevention in daily life, mainly through regular medical checkups to screen for diseases, active treatment of underlying diseases, and adjustment of lifestyles.

Regular medical checkups

Regular medical checkups can detect hidden diseases that may lead to sudden death. People with risk factors for sudden death, such as pre-existing heart disease or a family history of sudden death, should have more frequent checkups.

Active treatment of underlying diseases

If heart disease or other diseases that may lead to sudden death are already present, they should receive treatment as soon as possible. For example, patients with coronary heart disease need to be actively treated and take medication regularly; if there are clear indications, implantation of a cardioverter defibrillator should be recommended by a doctor.

Lifestyle Adjustment

Quit smoking and limit alcohol: Smoking will greatly increase the probability of cardiovascular and cerebrovascular system diseases.

Exercise regularly: regular exercise can better control weight. The intensity of exercise should be adapted to one’s own ability to exercise, avoiding strenuous exercise without a foundation.

Healthy diet: Do not consume too much fat and sugar. It is recommended to control the total calorie intake and consume more fresh vegetables and fruits.

Maintain a good lifestyle: avoid staying up late and get enough sleep.

First aid preparation