How many minutes can the heart stop? Cardiac arrest and cerebral coma: clinical death from the point of view of medicine

The main causes of cardiac arrest
Symptoms of cardiac arrest
Cardiac arrest and clinical death
Risk groups and further life

Increasingly in the modern world there are people with a sick heart. Cardiac arrest has become a common occurrence in medical practice. This all happens for a number of reasons and is often not related to the main diagnosis, that is, it has nothing to do with diseases. Stress is a phenomenon that affects not only the heart, but also the brain and other organs, leading to irreversible changes in the body. In most cases, doctors are able to cope with cardiac arrest, there are many methods of emergency care. You can always identify factors and risk groups, but it is important to do everything in order to avoid unpleasant situations, and even more so death. In many sources, you can find information on how to provide first aid and what symptoms may be in case of cardiac arrest.

The main causes of cardiac arrest

The heart is a complex organ of the human body, which ensures the vital activity of a person, supplying blood and oxygen to all muscles and organs. This is also a muscle that works rhythmically and harmoniously. Well-coordinated work ensures not only the well-being of a person, but also the normal functioning of the whole organism and each organ separately. This well-coordinated work can be disrupted by the following factors:

failure of the ventricles (fibrillation);
lack of bioelectric activity, its activity;
asistology;
tachycardia.

The above factors are direct causes. The most common of these is incorrect or chaotic work of the ventricles, in other words,. Simply put, each of them is a small feature associated with an overload or a violation in the rhythmic work of the heart muscle. Often, the upcoming stop can be indicated by breathing that does not correspond to normal, very rapid or with hoarseness.

Even before the moment of stopping, there may be a lack of oxygen in the tissues, especially due to a slow stop. In this case, the chances of a quick rescue are reduced, but the likelihood of preventing cardiac arrest itself increases. The main thing for both those around you and the one who is threatened is to pay attention to the changes in time and contact a specialist.

The reasons for this pathology can be different:

myocarditis;
ischemic diseases;
various metabolic processes;
sudden drop or rise in temperature.

All this is associated with lifestyle, if there are no pathological reasons for cardiac arrest. Smoking and alcohol affect the activity of the brain and heart, respectively, can cause cardiac arrest. This is very common among drug addicts. The most likely risk group after the age category is drug addicts. Drugs can affect the heart in a variety of ways. Treatment in such cases is useless, the only option for a drug addict is to get rid of addiction in all possible ways. Watching films, one can often observe how a patient's heart stops on the operating table during an operation. Manipulations in the body can, of course, lead to this, but this is most often affected by a change in temperature or a sharp blood loss, and, accordingly, a change in body temperature, a failure.

With low heart pressure, cardiac arrest is also possible. Often, a loss of consciousness can become a harbinger of this, and then, after 10 minutes, cardiac arrest.

Back to index

Symptoms of cardiac arrest

Influencing factors can become irreversible and lead to death. Symptoms of cardiac arrest can help you understand what exactly needs to be done to save a life and restore its work. Symptoms of cardiac arrest, detected in time, can often become an opportunity to save lives, since after a cardiac arrest, clinical death can occur, oxygen starvation of the organs begins.

Signs of cardiac arrest are convulsions, a gradual cessation of pulsation in the blood vessels, rare breathing and loss of breath, loss of consciousness, lack of reaction to light, a sharp change in complexion or skin in general. The symptoms are not easy, but with a cardiac arrest, a person stops his life, because not a single organ is able to function without a working heart.

The easiest way to track the symptoms in a person suffering from diabetes, coronary heart disease. Hoarseness and a change in complexion and skin for others can be the main signal that a person may experience cardiac arrest as a result of myocardial infarction. Using the example of those who suffer from drug addiction, we can say: dilated pupils also indicate that there is a reboot in the work of the heart muscle (this often causes it to stop). In this case, overwork due to irregular and unstable work of the heart can be eliminated by simple manipulations, as in first aid (indirect massage is done).

Cardiac arrest is the process by which an organ stops functioning. Various factors can cause this, and the result will be the clinical, and then the biological death of a person. It occurs due to the cessation of blood circulation, which leads to oxygen starvation of the body. If you do not help and do not make the heart beat in the first seven minutes, the victim's brain will die. A stop can occur in both young people and the elderly.

Heart disease

Causes of heart disease

Everyone can experience cardiac arrest, and its causes lie in heart disease and diseases of other organs. The following factors cause cardiac arrest:

Cardiac. This category of pathologies is the culprit of 90% of heart attacks. It includes:

rhythm disturbances;
Brugada syndrome;
ischemia;
heart attack;
thromboembolism of the arteries of the lungs;
rupture of an aneurysm in the aorta, acute heart failure;
arrhythmogenic and cardiogenic shock.

"Obstructive Sleep Apnea Syndrome" as an example. Because of this syndrome, a person experiences a short-term cardiac arrest at night. It is caused by abnormal heart activity.

The second reason is cardiac risk factors, which increase the likelihood of sudden stop in people with a diseased cardiovascular system. Factors include:

age from 50 years;
smoking;
frequent use of alcohol;
overweight;
physical exhaustion of the body;
stress, hypertension;
diabetes;
high cholesterol.

Extracardiac - non-cardiac pathologies and do not directly affect the heart, but they can cause a stop. Pathologies include:

asphyxia;
elderly age;
late stages of severe chronic pathologies;
various types of shock (caused by trauma or burns);
alcohol, drug or drug poisoning;
violence, drowning, injury, etc.

Reflex cardiac arrest is an example of a violent cause. Reflex cardiac arrest can be caused by a blow or happen with an electrical injury.

SIDS. This syndrome of sudden infant death requires separate consideration. It manifests itself when the child has not yet lived a year. It mostly happens at the age of 3 months. Cardiac arrest occurs during sleep at night. At the same time, the signs of cardiac arrest themselves do not appear in advance. There are factors that increase the risk of developing pathology:

how the baby lies on his stomach at night;
too soft bed;
sleep in a hot and stuffy room;
maternal smoking;
prematurity of the child;
multiple pregnancy;
intrauterine hypoxia;
the fetus has a developmental delay;
family predisposition;
in the first months after birth there was a severe infection.

These are the causes of cardiac arrest in humans.

heart attack

Heart attack symptoms

It is important to know the symptoms of cardiac arrest. Sudden cardiac arrest is an unpredictable pathology, as it is difficult to notice. With the development of pathology, the patient feels good, experiencing slight discomfort.

The condition worsens suddenly, the person grabs his heart and falls, losing consciousness. This is where it is important to know the symptoms, because they will distinguish cardiac arrest from ordinary fainting, which has similar symptoms.

Symptoms of pathology:

the pulse is not felt on the arteries;
there is no breathing or within 2 minutes it manifests itself in the form of convulsive wheezing;
the pupil does not constrict when exposed to light;
the body acquires an unnaturally pale, cyanotic color.

It is possible to determine cardiac arrest by symptoms if you know them and be able to notice them. In the aggregate, the condition looks like this: the patient falls, loses consciousness, turns pale, his lips turn blue, does not respond to braking and screams. If first aid is not provided to the victim within seven minutes, biological death will occur.

In a dream from cardiac arrest, death occurs in a different way. A person simply does not wake up and outwardly looks like he is sleeping.

Cardiac arrests such as sudden death and death in sleep are very dangerous. Both require attention, because otherwise first aid will not be provided in time and the person will die.

Sudden cardiac arrest

Diagnosis of pathologies

How to determine cardiac arrest? How to make a diagnosis? Most people do not know the answers to these questions. And this is bad, since almost 70% of these cardiac arrests occur outside the walls of medical facilities.

Mostly from cardiac arrest, people become ill at home, on the street or at work. Witnesses are ordinary people who do not have a medical education and are not able to provide qualified assistance.

However, knowing the basic actions, when every minute counts, a person will not be at a loss and will do everything right. The procedure is as follows:

If a person suddenly loses consciousness, you need to lightly hit him on the cheeks, shake him up and call loudly. This will allow you to understand what a person feels and whether he just fainted.
The next step is to check your breath. Attach your ear to the chest of the victim or throw back his head and push the jaw, then put your cheek to the patient's nostrils. This will allow you to feel and hear the breath, if any. Such methods are the most effective and allow you to do without improvised means and complex methods. For example: the use of a mirror brought to the mouth to recognize breathing.
Checking the pulse. To do this, locate the carotid artery located between the cervical muscle, larynx and angle of the mandible. If you do not feel a pulse, you need to start chest compressions.

Heartbeat

The arteries located on the wrist are not a reliable indicator. The severity of the patient's condition must be assessed during the first 20 seconds from the moment when cardiac activity stopped. Therefore, looking for a pulse on the wrist is not only useless, but also harmful.

Treatment

As soon as the diagnosis is made and an ambulance is called, you should begin to provide first aid. The victim should be laid on a hard surface. Then the resuscitation measures of the ABC algorithm come into play.

ABC consists of three items.

Ensure airway patency. To do this, the person's head is thrown back, and the lower jaw is pushed forward. After that, a finger wrapped in a cloth cleans the oral cavity from vomiting or mucus.
Create artificial lung ventilation. This is done in two ways: mouth-to-mouth and mouth-to-nose. For the first method, pinch the nose of the victim with two fingers and blow air into the mouth. In order not to come into contact with the patient's saliva, put on a scarf or napkin.
Perform a closed heart massage. However, the heart, as soon as it stops, must receive a precordial beat. It is applied from a distance of about 25 cm with a fist to the sternum, before starting a heart massage. It is effective only in the first half a minute after cardiac arrest and only with ventricular fibrillation.

These three points, performed correctly, will help save a human life. Particular attention should be paid to the order in which they are performed. The sequence is due to the fact that for the brain, blood supply is a priority, and not ventilation of the lungs.

Heart massage

In order for a heart massage to be effective, certain actions must be performed in the correct order.

First, locate the lower third of the sternum. Then measure up the distance from its lower edge, equal to two transverse fingers. Clasp your hands in a lock so that one hand is on top of the other. Straighten your arms to rest them on the lower third.

When pressing, it is important to keep your arms straight. This will avoid fractures of the ribs, and the pressure exerted will be optimal. To achieve a greater effect, it is recommended to bend the patient's legs and raise them 35 ° above the floor.

Massage

Ambulance

What drugs are administered to the patient first? The medical team uses special tools to start the heart. One such drug most commonly used in cardiac arrest is epinephrine. There are also several other means for this: Atropine, Norepinephrine and others. All of them stimulate cardiac activity.

Then heart contractions are diagnosed or an electrocardiogram is done. Then a defibrillator is used to start the heart. The defibrillator has electrodes that are applied to the patient's chest. An electric discharge is launched through them, which should start the heart.

The defibrillator is used already on the move in the ambulance. This is necessary for the patient to survive to the intensive care unit of the hospital. The defibrillator can also be used in the clinic.

Medicines for the heart

It is worth considering in detail the drugs (Lidocaine, Adrenaline and others), their purpose and properties. After all, even though the defibrillator takes on the main function of starting the heart muscle, a much greater result is achieved in combination with the necessary drugs.

Necessary drugs - Adrenaline, Atropine, Lidocaine, sodium bicarbonate, magnesium sulfate and calcium:

Adrenaline is used to make the heart beat faster and stronger.
Atropine is excellent for asystole.
Lidocaine helps fight arrhythmia.
Sodium bicarbonate is used in cases of prolonged stopping, especially if acidosis or hyperkalemia has occurred.
Magnesium sulfate stabilizes and stimulates heart cells.
Calcium helps to cope with hyperkalemia.

When used correctly, Atropine, Lidocaine and other drugs give an excellent result, multiplying the chances of the patient to survive.

Resuscitation and consequences

After delivering the patient by ambulance and injections (Lidocaine, Atropine, etc.), he must be in intensive care for a certain time. You may need surgery. In this case, during the operation, a pacemaker is implanted in the heart, which will maintain the heart rhythm.

Even after discharge, the patient must strictly follow the instructions of doctors: give up bad habits, drink the right pills and periodically undergo heart examinations.

By using glycosides and leading a healthy lifestyle, this situation can be avoided. And then the chance to live to a ripe old age will increase significantly.

The consequences of cardiac arrest are very serious. These are memory loss, hallucinations, convulsions, headaches, blurred vision and hearing.

Help

myths

Now on the Internet there are many myths associated with cardiac arrest. They feature cognac, SCP 001, a dream book, and the like. We will try to dispel at least some of them.

dreams

Let's start with the dream book. Many lovers of traditional medicine firmly believe that it is possible to predict and prevent cardiac arrest if you correctly interpret your dreams.

It is believed that a stop will occur if in a dream you see the heart from the side. And you can prevent it if you take control of sleep and present a different picture in accordance with the description in the book.

The result of such self-hypnosis is death. Therefore, you should not risk your health by relying on a book about dreams, but seek help from a doctor.

SCP 001

SCP 001 is a myth about a mysterious file containing terrible secrets. If you believe the data on the site, then by going to it, a person will face a unique protection. If you scroll down the page and read the text of SCP 001, then in a few seconds his heart will stop.

Many believe in SCP 001 and are seriously worried about it. However, there are no victims so far, and, apparently, this is another joke from a series of “damned chain letters”

Cognac and heart

The myth of cognac Many people who survived the shutdown love cognac. And many of them are sure that it is good for the heart. And therefore often use it more often than drugs.

Cognac does not cure, but can lead to a violation of cardiac activity. Therefore, its use leads to malfunctions that will cause cardiac arrest.

So people suffering from heart disease should refrain from using it.

You can find more information about cardiac arrest in the video:

What do you need to know to provide first aid for cardiac arrest?

Clinical death can quickly become biological if certain first aid steps are not taken. In order to provide this very help, you need to know the signs of cardiac arrest, their manifestations and coordination of actions to resuscitate a person. The importance of such knowledge is confirmed by statistics, according to which about 200 thousand people die from cardiac arrest per week worldwide, while 90% of deaths could be reversible with proper first aid.

Why does the heart stop beating

The cause of cardiac arrest is often a violation of the functional abilities of this organ. Medicine distinguishes two main ways leading to clinical death:

Ventricular fibrillation accounts for 90% of recorded cases of clinical death. In this condition, the heart muscles give in to rapid chaotic contraction, which is not accompanied by the release of blood flow.
Asystole accounts for only 5%, at which the heart muscles stop contracting completely. This leads to initial oxygen starvation of cells, after which to clinical death.
The remaining 5% includes electromechanical dissociations and damage to the muscles of the heart, which lead to its stop during an accident, surgery, etc.
It should be noted that the following factors significantly increase the risk of myocardial arrest:

elderly age;
bad habits (smoking, alcohol);
excess weight;
prolonged exposure to stress;
the presence of hypertension or hypotension;
diabetes.

More about cardiac arrest in sleep

It happens that there is a cardiac arrest in a dream. Often, pathologies of the cardiovascular system become the cause of clinical death in a dream, but it happens that the heart stops in healthy people. In medicine, this "microdeath" is called obstructive sleep apnea syndrome. According to studies that were conducted in the 70s, the duration of nighttime cardiac fading (in 68% of subjects with respiratory arrest) can reach up to 13 seconds, while the person does not show any signs of myocardial arrest, but the cells of the body experience oxygen starvation.

Particular attention should be paid to the syndrome of sudden infant mortality, which is commonly called "the lullaby death of an infant." The age contingent prone to such a syndrome is infants 2–4 months old, in whom the heart stops at night without the presence of previous health problems. Factors that increase the risk of developing such a tragedy include:

sleep of the baby in the position on the stomach;
fever and stuffiness in the room where a small child sleeps;
prematurity of the baby;
the presence of intrauterine hypoxia in a child;
transmission of an infectious disease in the first months of life.

Signs of cardiac arrest

Cardiac arrest is preceded by characteristic signs by which it can be determined that the body is amenable to irreversible processes.

The person faints. In an unconscious state, short convulsions of the whole body or limbs may occur.
Breathing becomes agonal (up to two minutes there are rare respiratory movements in the form of short, sharp, convulsive wheezing) or is completely absent.
The pulse is not felt on the main blood vessels.
No pupillary response to light stimulation. It is checked by shining a flashlight into the pupil, when the heart stops, they are expanded and do not narrow when exposed to direct light.
The skin of the face takes on a bluish-gray color as blood circulation stops.

Since only 5-7 minutes are allowed to restore the functioning of the myocardium, when seeing the first signs of cardiac arrest, it is necessary to quickly assess the person’s condition, for this you should:

call out, pat on the cheeks;
if there is no reaction, feel the heartbeat and pulse;
check for breathing
Be sure to call an ambulance.

What first aid should be provided in case of cardiac arrest and lack of breathing

If a person has the above signs that indicate the non-functioning of the myocardium, then first aid should be provided in case of cardiac and respiratory arrest. This assistance is divided into:

emergency pre-medical;
medical.

First aid for clinical death

If the person with you has fainted or is found unconscious, and checking the signs indicates clinical death, then the following resuscitation steps should be taken, since life can be saved only for 5-7 minutes after the end of the functioning of the heart muscles.

Lay the person on a hard, flat surface. Call an ambulance.
Monitor airway patency. To do this, you need to carefully throw the patient's head, but before that, check for vomit in the mouth, since it is quite possible that the loss of consciousness was preceded by a gag reflex.
Perform chest compressions. During its holding, the arms should be straightened, not bent at the elbows. On the chest on the right side, lay the left (the one that is weaker) hand palm down. Place the palm of the right hand perpendicularly. After establishing the hands with a “cross”, it is necessary to perform five pressures with straightened arms. You should not press hard, as there is a risk of breaking the ribs, which will further worsen the condition of the person. Normally, in 60 seconds, 100 clicks should be done.
Make artificial respiration. To do this, after ensuring the patency of the respiratory tract, you should put a clean cloth (handkerchief or napkin) on the mouth / nose of the victim. There are two procedures for the procedure: mouth-to-mouth and mouth-to-nose. Holding your mouth or nose (depending on the chosen method), blow air through your mouth into the lungs of a lying person.
Actions for pre-medical resuscitation involve the combination of artificial respiration and chest compressions. Ideally, they are performed by two people, one of whom inhales air into the lungs after the fifth pressure of the second person. If one person is engaged in resuscitation, then after making fifteen clicks, you need to take one breath into the lungs, then they will return to indirect massage again.

First aid

Resuscitation should continue until the ambulance arrives. Doctors will administer to the victim drugs that promote the "establishment" of the myocardium and try to cause a heartbeat through an electrical discharge. Further, the patient is taken to the ambulance with subsequent hospitalization and treatment.

Once a year, at least, the media report another death from sudden cardiac arrest: an athlete right on the field during a game or a schoolboy in physical education classes. But many people die for the same reason, falling asleep and not waking up. What is it, is cardiac arrest so sudden and can it be foreseen, MedAboutMe figured out

By "sudden death from cardiac arrest" is meant, in the absence of other options, the death of a person who was in a stable condition within the next hour. Cardiac arrest is not such a rare event, unfortunately. According to the Ministry of Health, only in Russia every year from 8 to 16 people die from sudden cardiac arrest for every 10 thousand of the population, which is 0.1-2% of all adult Russians. In the whole country, 300 thousand people die this way every year. 89% of them are men.

In 70% of cases, sudden cardiac arrest occurs outside the walls of the hospital. In 13% - in the workplace, in 32% - in a dream. In Russia, the chances of survival are low - only one person out of 20. In the US, the probability that a person will survive is almost 2 times higher.

The main cause of death most often is the lack of timely assistance.

Hypertrophic cardiomyopathy.

One of the most famous reasons why a person who does not complain about his health can die. Most often, the name of this disease flashes in the media in connection with the sudden death of famous athletes and little-known schoolchildren. So, in 2003, football player Marc-Vivier Foe died of hypertrophic cardiomyopathy right during the game, in 2004 - football player Miklós Feher, in 2007 - strongman Jesse Marunde, in 2008 - Russian hockey player Alexei Cherepanov, in 2012 - football player Fabrice Muamba, in January of this year - a 16-year-old schoolboy from Chelyabinsk... The list goes on.

The disease often affects young people under the age of 30. At the same time, despite the "sports" history of the disease, most of the deaths occur at the time of minor exertion. Only 13% of deaths occurred during a period of increased physical activity.

In 2013, scientists found a gene mutation that causes thickening of the myocardium (most often we are talking about the wall of the left ventricle). In the presence of such a mutation, the muscle fibers are not arranged in an orderly manner, but randomly. As a result, a violation of the contractile activity of the heart develops.

Other causes of sudden cardiac arrest include:

Ventricular fibrillation.

Chaotic and therefore hemodynamically inefficient contraction of individual sections of the heart muscle is one of the varieties of arrhythmia. This is the most common type of sudden cardiac arrest (90% of cases).

Ventricular asystole.

The heart simply stops working, its bioelectrical activity is no longer recorded. This condition causes 5% of cases of sudden cardiac arrest.

Electromechanical dissociation.

The bioelectrical activity of the heart is preserved, but there is practically no mechanical activity, that is, impulses go on, but the myocardium does not contract. Doctors note that this condition practically does not occur outside the hospital.

Scientists point out that most people who experience sudden cardiac arrest also had the following conditions:

mental disorders (45%);
asthma (16%);
heart disease (11%);
gastritis or gastroesophageal reflux disease (GERD) (8%).

Literally in a few seconds from its beginning, develop:

weakness and dizziness;
after 10-20 seconds - loss of consciousness;
after another 15-30 seconds, the so-called tonic-clonic convulsions develop,
breathing rare and agonal;
clinical death occurs at 2 minutes;
pupils dilate and stop responding to light;
the skin turns pale or becomes bluish (cyanosis).

The chances of survival are low. If the patient is lucky and there is a person nearby who is able to conduct an indirect heart massage, the likelihood of surviving the syndrome of sudden cardiac arrest increases. But for this it is necessary to "start" the heart no later than 5-7 minutes after it stopped.

Danish scientists analyzed cases of sudden death from cardiac arrest. And it turned out that the heart, even before it stopped, let know that something was wrong with it.

In 35% of patients with sudden death syndrome from arrhythmia, at least one symptom was observed that speaks of heart disease:

fainting or pre-syncope - in 17% of cases, and this was the most common symptom;
pain in the chest;
The patient has already undergone successful resuscitation of cardiac arrest.

As well as 55% of people who died from hypertrophic cardiomyopathy, more than 1 hour before their sudden death, experienced:

fainting (34%);
chest pain (34%);
shortness of breath (29%).

American researchers also point out that every second person who was overtaken by sudden cardiac arrest experienced manifestations of cardiac dysfunction - and not an hour or two, but in some cases several weeks before the critical moment.

Thus, 50% of men and 53% of women noted chest pain and shortness of breath 4 weeks before the attack, and almost all (93%) had both symptoms 1 day before sudden cardiac arrest. Only one in five of these people went to the doctors. Of these, only a third (32%) managed to escape. But from the group that did not seek help at all, even fewer survived - only 6% of patients.

The complexity of the prediction of sudden death syndrome lies also in the fact that not all of these symptoms appear at the same time, so it is impossible to accurately track the critical deterioration in health. 74% of people had one symptom, 24% had two, and only 21% had all three.

So, we can talk about the following main signs that may precede sudden cardiac arrest:

Chest pain: 1 hour to 4 weeks before attack.
Difficulty breathing, shortness of breath: from an hour to 4 weeks before an attack.
Fainting: shortly before the attack.

If these signs are present, you should contact a cardiologist and undergo an examination.

If you have chest pain and shortness of breath, you should immediately consult a doctor for a heart examination. Remember: Seeking medical attention in a timely manner increases a person's chance of life with sudden cardiac arrest by 6 times.
A person who has experienced sudden cardiac arrest needs immediate chest compressions.
Do not try to give the victim any medication, including the popular nitroglycerin. It may worsen the patient's condition.

Take the test

Do you know what your blood pressure is? But it is one of the main indicators of the state of health. We suggest taking a small test that will allow you to decide on this issue and figure out what should be done to maintain normal blood pressure.

Cardiac arrest is a complete cessation of ventricular contractions or a severe loss of pumping function. At the same time, electrical potentials disappear in myocardial cells, the pathways for conducting impulses are blocked, and all types of metabolism are quickly disrupted. The affected heart is unable to push blood into the vessels. Stopping blood circulation poses a threat to human life.

According to WHO statistics, 200,000 people around the world stop their hearts every week. Of these, about 90% die at home or at work before receiving medical care. This indicates a lack of public awareness of the importance of training in emergency measures.

The total number of deaths from sudden cardiac arrest is greater than from cancer, fires, traffic accidents, AIDS. The problem concerns not only the elderly, but also people of working age, children. Some of these cases can be prevented. Sudden cardiac arrest does not necessarily occur as a result of a serious illness. Such a defeat is possible against the background of full health, in a dream.

The main types of cessation of cardiac activity and the mechanisms of their development

The causes of cardiac arrest according to the mechanism of development are hidden in a sharp violation of its functional abilities, especially excitability, automatism and conductivity. Types of cardiac arrest depend on them. Cardiac activity can stop in two ways:

asystole (in 5% of patients);
fibrillation (in 90% of cases).

Asystole is the complete cessation of ventricular contraction in the diastolic phase (during relaxation), rarely in systole. The “order” to stop can come to the heart from other organs as a reflex, for example, during operations on the gallbladder, stomach, and intestines.

With reflex asystole, the myocardium is not damaged, has a fairly good tone

In this case, the role of the vagus and trigeminal nerves has been proven.

Another option is asystole against the background:

general oxygen deficiency (hypoxia);
elevated levels of carbon dioxide in the blood;
shifts in acid-base balance towards acidosis;
altered electrolyte balance (increase in extracellular potassium, decrease in calcium).

These processes, taken together, negatively affect the properties of the myocardium. The process of depolarization, which is the basis of myocardial contractility, becomes impossible, even if conduction is not impaired. Myocardial cells lose active myosin, which is necessary for obtaining energy in the form of ATP.

With asystole in the systole phase, hypercalcemia is observed.

fibrillation of the heart- this is a broken connection between cardiomyocytes in coordinated actions to ensure a general contraction of the myocardium. Instead of synchronous work that causes systolic contraction and diastole, there are many disparate areas that contract on their own.

The frequency of contractions reaches 600 per minute and above

In this case, the ejection of blood from the ventricles suffers.

Energy costs are much higher than normal, and there is no effective reduction.

If fibrillation captures only the atria, then individual impulses reach the ventricles and blood circulation is maintained at a sufficient level. Attacks of short-term fibrillation can end on their own. But such tension of the ventricles cannot provide hemodynamics for a long time, energy reserves are depleted and cardiac arrest occurs.

Other mechanisms of cardiac arrest

Some scientists insist on isolating electromechanical dissociation as a separate form of cessation of cardiac contractions. In other words, myocardial contractility is preserved, but not sufficient to ensure the pushing of blood into the vessels.

At the same time, there is no pulse and blood pressure, but the following are recorded on the ECG:

correct contractions with low voltage;
idioventricular rhythm (from the ventricles);
loss of activity of the sinus and atrioventricular nodes.

The condition is caused by inefficient electrical activity of the heart.

In addition to hypoxia, impaired electrolyte composition and acidosis, hypovolemia (a decrease in total blood volume) is important in pathogenesis. Therefore, more often such signs are observed with hypovolemic shock, massive blood loss.

Since the 70s of the last century, the term "Obstructive Sleep Apnea Syndrome" has appeared in medicine. Clinically, it was manifested by a short-term cessation of breathing and cardiac activity at night. To date, a lot of experience has been accumulated in the diagnosis of this disease. According to the Research Institute of Cardiology, nocturnal bradycardia was found in 68% of patients with respiratory arrest. At the same time, according to a blood test, pronounced oxygen starvation was observed.

The device allows you to record the respiratory rate and heart rate

The picture of heart damage was expressed:

in 49% - sinoatrial blockade and stop of the pacemaker;
19% - blockade with atrial fibrillation;
in 5% - a combination of different forms of bradyarrhythmias.

The duration of cardiac arrest was recorded for more than 3 seconds (other authors indicate 13 seconds).

During the waking period, none of the patients experienced fainting or any other symptoms.

Researchers believe that the main mechanism of asystole in these cases is a pronounced reflex effect from the respiratory organs, coming through the vagus nerve.

Causes of cardiac arrest

Among the causes can be distinguished directly cardiac (cardiac) and external (extracardial).

The main cardinal factors are:

ischemia and inflammation of the myocardium;
acute obstruction of the pulmonary vessels due to thrombosis or embolism;
cardiomyopathy;
high blood pressure;
atherosclerotic cardiosclerosis;
disturbances of a rhythm and conductivity at defects;
development of cardiac tamponade in hydropericardium.

Extracardiac factors include:

oxygen deficiency (hypoxia) caused by anemia, asphyxia (suffocation, drowning);
pneumothorax (the appearance of air between the layers of the pleura, unilateral compression of the lung);
loss of a significant amount of fluid (hypovolemia) with trauma, shock, incessant vomiting and diarrhea;
metabolic changes with a deviation towards acidosis;
hypothermia of the body (hypothermia) below 28 degrees;
acute hypercalcemia;
severe allergic reactions.

Pneumothorax of the right lung sharply displaces the heart to the left, with a high risk of asystole

Indirect factors that affect the stability of the body's defenses are important:

excessive physical overload of the heart;
elderly age;
smoking and alcoholism;
genetic predisposition to rhythm disturbances, changes in electrolyte composition;
suffered electrical injury.

A combination of factors greatly increases the risk of cardiac arrest. For example, alcohol intake by patients with myocardial infarction causes asystole in almost 1/3 of patients.

The negative impact of drugs

Drugs that cause cardiac arrest are used for treatment. In rare cases, intentional overdose has been fatal. This should be proven to the judicial authorities. When prescribing drugs, the doctor focuses on the age, weight of the patient, diagnosis, warns of a possible reaction and the need to re-see a doctor or call an ambulance.

The phenomena of overdose occur when:

non-compliance with the regimen (taking pills and alcohol);
intentionally increasing the dose (“I forgot to drink in the morning, so I’ll take two at once”);
in combination with folk methods of treatment (St.
carrying out general anesthesia against the background of incessant medication.

The use of St.

The most common causes of cardiac arrest are:

hypnotics from the group of barbiturates;
narcotic drugs for pain relief;
groups of β-blockers for hypertension;
drugs from the group of phenothiazines prescribed by a psychiatrist as a sedative;
tablets or drops of cardiac glycosides, which are used to treat arrhythmias and decompensated heart failure.

It is estimated that 2% of cases of asystole are drug related.

Only a specialist can determine which drugs have the most optimal indications and have the least properties for accumulation, addiction. Do not do this on the advice of friends or on your own.

Diagnostic signs of cardiac arrest

Cardiac arrest syndrome includes early signs of a near-death state. Since this phase is considered reversible during effective resuscitation, every adult should know the symptoms, since a few seconds are allowed for reflection:

Complete loss of consciousness - the victim does not respond to a shout, braking. It is believed that the brain dies 7 minutes after cardiac arrest. This is an average figure, but the time can vary from two to eleven minutes. The brain is the first to suffer from oxygen deficiency, the cessation of metabolism causes cell death. Therefore, there is no time to argue how long the brain of the victim will live. The sooner resuscitation is started, the greater the chance of survival.
The inability to determine the pulsation on the carotid artery - this symptom in diagnosis depends on the practical experience of others. In its absence, you can try to listen to heartbeats by putting your ear to the bare chest.
Impaired breathing - accompanied by rare noisy breaths and intervals of up to two minutes.
"Before our eyes" there is an increase in the change in skin color from pallor to blue.
The pupils dilate after 2 minutes of cessation of blood flow, there is no reaction to light (narrowing from a bright beam).
The manifestation of convulsions in individual muscle groups.

If an ambulance arrives at the scene, then asystole can be confirmed by an electrocardiogram.

What are the consequences of cardiac arrest?

The consequences of circulatory arrest depend on the speed and correctness of emergency care. Prolonged oxygen deficiency of organs causes:

irreversible foci of ischemia in the brain;
affects the kidneys and liver;
with vigorous massage in the elderly, children, fractures of the ribs, sternum, development of pneumothorax are possible.

The mass of the brain and spinal cord together is only about 3% of the total body weight. And for their full functioning, up to 15% of the total cardiac output is necessary. Good compensatory capabilities make it possible to preserve the functions of the nerve centers with a decrease in the level of blood circulation to 25% of the norm. However, even indirect massage allows you to maintain only 5% of the normal level of blood flow.

Consequences on the part of the brain can be:

partial or complete memory impairment (the patient forgets about the injury itself, but remembers what happened before it);
blindness accompanies irreversible changes in the visual nuclei, vision is rarely restored;
paroxysmal cramps in the arms and legs, chewing movements;
different types of hallucinations (auditory, visual).

Statistics show actual recovery in 1/3 of cases, but full recovery of brain and other organs functions occurs only in 3.5% of cases of successful resuscitation

This is due to the delay in assistance in a state of clinical death.

Prevention

Cardiac arrest can be prevented by following the principles of a healthy lifestyle, avoiding factors that affect blood circulation.

Rational nutrition, quitting smoking, alcohol, daily walks for people with heart disease are no less important than taking pills.

Control over drug therapy requires remembering about a possible overdose, slowing of the pulse. It is necessary to learn how to determine and count the pulse, depending on this, coordinate the dose of drugs with the doctor.

Unfortunately, the time to provide medical care in case of cardiac arrest is so limited that it is not yet possible to achieve full-fledged resuscitation in the community.