What Is Advanced Cardiac Life Support?

Sudden cardiac death refers to natural deaths caused by loss of consciousness due to various cardiac causes, and the death occurs within 1 hour after the onset of symptoms. Sudden cardiac death is mainly manifested as: death within 1 hour after an acute attack of chest pain, shortness of breath, etc. caused by the heart; there is often no sign before discovery; once it occurs, the effective rescue time is short.

Basic Information

nickname: Sudden cardiac death

Visiting department: Emergency Department
Disease characteristics: Chest pain and shortness of breath caused by heart

Causes of sudden cardiac death

Organic heart disease

1) The occurrence of most sudden cardiac death is related to organic heart disease, such as coronary heart disease, cardiomyopathy, and valvular heart disease.

2) The other type of sudden cardiac death is caused by malignant arrhythmias. It occurs as a series of pathophysiological abnormalities caused by the interaction of factors such as coronary vascular events, myocardial damage, abnormal cardiac metabolism, and / or changes in autonomic nervous tension. result.

2. Hypertension with left ventricular hypertrophy

Hypertension combined with left ventricular hypertrophy is another major cause. Due to long-term hypertension, myocardial compensatory hypertrophy and secondary myocardial tissue damage lead to the formation of an electrophysiological basis for malignant arrhythmias. Ventricular hypertrophy is also the pathological basis of heart failure, and the incidence of sudden death is very high in patients with heart failure.

3. Other cardiovascular diseases that can cause sudden death

E.g:

1) Non-atherosclerotic coronary artery abnormalities;

2) Cardiomyopathy and heart failure, including arrhythmogenic right ventricular cardiomyopathy, hypertrophic cardiomyopathy, dilated cardiomyopathy, and myocardial densification;

3) Myocardial inflammation, infiltration, and degenerative changes;

4) cardiac tumors;

5) Congenital heart disease;

6) Primary ECG abnormalities, including severe bradycardia (sick sinus node syndrome, high or complete atrioventricular block), congenital or acquired long QT syndrome, short QT syndrome, bru Gada syndrome, etc .;

7) Electrolyte disorders, such as hypokalemia, hypomagnesemia;

8) Arrhythmias associated with neurohumoral or central nervous system effects;

9) Tumor at the atrioventricular node;

10) Aortic dissection;

11) Pulmonary embolism.

Clinical manifestations of sudden cardiac death

The clinical process that causes sudden cardiac death can be divided into 4 periods: prodromal phase, terminal event phase, cardiac arrest, and biological death. They are in different periods and have different performance.

Precursory period

There may be no obvious manifestations, and some patients may experience symptoms such as palpitation, shortness of breath, fatigue, and chest pain.

End event period

The main manifestations are: dizziness, darkening; sudden palpitation; rapid increase in breathing difficulties; severe chest pain.

3. cardiac arrest

Main manifestations are: sudden loss of consciousness; disappearance of aortic pulsation; accompanied by local or systemic convulsions; intermittent breathing until stopped; pale or cyanosis.

4. Biological death

If biological death occurs, that is, permanent loss of organ functions such as brain, heart, lung, liver, kidney, etc., it will no longer be possible to rescue successfully.

Sudden cardiac death

At different times, the examinations that need to be done are not the same. Doctors may do physical examinations, ECGs, ECG monitoring, echocardiography, laboratory examinations, and so on.

Physical examination

By touching the carotid or femoral pulse, the doctor can measure the blood pressure, observe the changes in breathing, skin color and pupil, and the nerve reflex, etc., to determine the period of the patient.

2. ECG

The waveform of the electrocardiogram can further determine the presence or absence of arrhythmia.

3. Echocardiography

By analyzing the echocardiogram, you can find abnormalities in the structure of the heart, assess cardiac function, and then identify the potential risk of sudden death.

4. Coronary angiography

Coronary angiography can clarify the condition of the coronary arteries and determine whether a myocardial infarction has occurred.

5. Blood routine, myocardial injury marker detection, blood electrolyte analysis

These tests can help doctors diagnose the cause and assess the heart and overall condition.

Sudden cardiac death diagnosis

Doctors will comprehensively consider the medical history, symptoms, and results of physical examination and electrocardiogram to determine whether sudden cardiac death has occurred.

1. Have a history of heart disease, such as coronary heart disease, myocarditis, and cardiomyopathy.

2. Sudden loss of consciousness.

3. Physical examination revealed no aortic (carotid or femoral) pulsation, no spontaneous breathing, undetectable blood pressure, and disappearance of heart sounds.

Differential diagnosis of sudden cardiac death

If there is a sudden loss of consciousness, it may be sudden cardiac death, or it may be sudden cardiac arrest.

Sudden cardiac death and cardiac arrest are different concepts. Sudden cardiac arrest is characterized by sudden loss of consciousness and disappearance of pulse. With timely and effective rescue, cardiac arrest may be reversed and recovered; however, delayed rescue or improper measures often lead to death. Cardiac arrest is the leading cause of sudden cardiac death, and sudden cardiac death indicates that death has occurred. Sudden cardiac death is an important factor threatening human health.

Sudden cardiac death treatment

Once a cardiac arrest is diagnosed, CPR should be performed immediately, including basic life support, advanced basic life support, and post-resuscitation management.

Drug treatment

(1) Antiarrhythmic treatment

Commonly used drugs include the following.

Amiodarone: used for recurrent ventricular tachycardia and ventricular fibrillation after cardioversion.

Lidocaine: the drug of choice for the treatment of ventricular arrhythmias, especially acute myocardial infarction with ventricular arrhythmias.

Adrenaline: used for ventricular fibrillation, cardiac arrest and electro-mechanical separation.

Atropine: used for the treatment of sinus bradycardia, high atrioventricular block and ventricular arrest with hemodynamic disorders.

Isoprenaline: Used for bradycardia or ventricular arrhythmias that are not effective with atropine.

Sodium bicarbonate: The therapeutic effect on cardiac arrest is unclear, and it should be applied after cardiopulmonary resuscitation, defibrillation, improved ventilation and medication.

(2) Increase cardiac output and maintain blood pressure

Commonly used drugs include epinephrine, norepinephrine, dopamine, dobutamine, alamin, and calcium preparations. Intravenous infusion, the drug dose and the infusion rate must be strictly controlled.

2. Surgical treatment

Artificial cardiac pacing is suitable for those with high AV block, severe bradycardia, or ventricular arrest.

3. Other treatments

(1) Basic life support

Open the airway: Once the cardiac arrest is confirmed, confirm the safety at the scene, perform CPR on the spot, and call for help at the same time.

Artificial Respiration: Quickly determine if breathing has stopped. If there is no spontaneous breathing, the mouth-to-mouth artificial respiration is performed.

Chest compressions: Check for carotid pulses. If the arterial pulses disappear, immediately apply chest compressions. Adults press the sternum at least 5 cm, but not more than 6 cm. Compression for children and infants is at least 1/3 of the anterior-posterior diameter of the chest (approximately 5 cm for children and approximately 4 cm for infants). The compression frequency is about 100 to 120 times / minute, and at the junction of the middle and lower 1/3 of the sternum.

Artificial respiration and chest compressions are performed at the same time: if a person is performing CPR, the ratio of chest compressions to artificial respiration is about 30: 2.

(2) Advanced Basic Life Support

Apply a simple respirator as early as possible: pressurize oxygen through a mask and prepare an intubation, simple respirator, and ventilator.

Establish venous access: timely infusion of various rescue drugs. In some patients, puncture is difficult due to the collapse of the surrounding veins, and bone marrow puncture, external jugular vein, or femoral vein cannula can be selected. Some drugs, such as lidocaine, atropine, and epinephrine, can be instilled through a tracheal cannula.

Early ECG monitoring and ECG examination.

As soon as necessary, cardioversion or electrodefibrillation treatment.

(3) Post-recovery treatment

Cardiopulmonary resuscitation needs to maintain effective circulation and breathing to prevent cerebral hypoxia and cerebral edema.

If blood pressure drops, in addition to symptomatic treatment, the cause should be analyzed and treated properly.

Those with conditions should perform hemodynamic monitoring to guide medication.

For refractory shock, attention should be paid to other complications after CPR, such as pneumothorax, pericardial tamponade or abdominal organ damage.

If left ventricular dysfunction occurs, appropriate cardiac, diuretic, and vasodilator treatments are appropriate.

Sudden cardiac death hazard

Sudden cardiac death is not only a loss of life, but also a huge blow to family and relatives.

Prognosis of sudden cardiac death

Cardiac arrest occurs before sudden cardiac death, and the survival rate after cardiac arrest is very low, and most of them cannot be successfully rescued, but active rescue is likely to save lives.

Sudden cardiac death prevention

The prevention of sudden cardiac death is a comprehensive measure. According to the patient's condition, it is divided into primary prevention and secondary prevention.

Primary prevention

1. Mainly control risk factors and underlying diseases. Patients with coronary heart disease, high-risk hypertension, cardiac insufficiency, and acute coronary syndrome should actively cooperate with their doctors for treatment.

2. Maintain a healthy lifestyle and exercise regularly to avoid overwork.

3. Avoid overeating, quitting smoking, limiting alcohol, healthy and reasonable diet.

4. Avoid excessive stress or excitement and maintain a good mood.

2. Secondary prevention

Implantable cardioversion defibrillator can also effectively prevent sudden cardiac death caused by arrhythmia.