The most reliable sign of biological death is. Clinical and biological death concept of clinical and biological death

A living organism does not die simultaneously with the cessation of breathing and cessation of cardiac activity, therefore, even after they stop, the body continues to live for some time. This time is determined by the brain’s ability to survive without oxygen supplied to it; it lasts 4–6 minutes, on average 5 minutes.

This period, when all the extinct vital processes of the body are still reversible, is called clinical death. Clinical death can be caused by heavy bleeding, electrical trauma, drowning, reflex cardiac arrest, acute poisoning, etc.

Clinical death

Signs of clinical death:

1) absence of pulse in the carotid or femoral artery;
2) lack of breathing;
3) loss of consciousness;
4) wide pupils and their lack of reaction to light.

Therefore, first of all, it is necessary to determine the presence of blood circulation and breathing in the patient or victim.

Determination of signs of clinical death:

1. Absence of pulse in the carotid artery is the main sign of circulatory arrest;

2. Lack of breathing can be checked by visible movements of the chest during inhalation and exhalation, or by placing your ear to the chest, hearing the sound of breathing, feeling (the movement of air during exhalation is felt by the cheek), and also by bringing a mirror, a piece of glass or a watch glass, or a cotton swab to your lips or thread, holding them with tweezers. But it is precisely on the determination of this characteristic that one should not waste time, since the methods are not perfect and unreliable, and most importantly, they require a lot of precious time for their determination;

3. Signs of loss of consciousness are a lack of reaction to what is happening, to sound and pain stimuli;

4. The victim’s upper eyelid is raised and the size of the pupil is determined visually, the eyelid lowers and immediately rises again. If the pupil remains wide and does not narrow after lifting the eyelid again, then we can assume that there is no reaction to light.

If one of the first two of the 4 signs of clinical death is determined, then you need to immediately begin resuscitation. Since only timely resuscitation (within 3–4 minutes after cardiac arrest) can bring the victim back to life. Resuscitation is not performed only in the case of biological (irreversible) death, when irreversible changes occur in the tissues of the brain and many organs.

Biological death

Signs of biological death:

1) drying of the cornea;
2) the “cat’s pupil” phenomenon;
3) decrease in temperature;.
4) body cadaveric spots;
5) rigor mortis

Determination of signs of biological death:

1. Signs of drying out of the cornea are the loss of the iris of its original color, the eye appears to be covered with a whitish film - a “herring shine”, and the pupil becomes cloudy.

2. The thumb and forefinger squeeze the eyeball; if the person is dead, then his pupil will change shape and turn into a narrow slit - a “cat’s pupil.” This cannot be done in a living person. If these 2 signs appear, this means that the person died at least an hour ago.

3. Body temperature drops gradually, by about 1 degree Celsius every hour after death. Therefore, based on these signs, death can only be confirmed after 2–4 hours or later.

4. Purple cadaveric spots appear on the underlying parts of the corpse. If he lies on his back, then they are identified on the head behind the ears, on the back of the shoulders and hips, on the back and buttocks.

5. Rigor mortis is a post-mortem contraction of skeletal muscles “from top to bottom,” i.e. face – neck – upper limbs – torso – lower limbs.

Full development of signs occurs within 24 hours after death.

Clinical death- this is when there are no signs of life, but all organs and tissues of the body are still alive. Clinical death is a reversible condition. Biological death- this is when the main human organs die: the brain, heart, kidneys, lungs. Biological death is an irreversible condition.

Without resuscitation, biological brain death occurs 5 minutes after cardiac arrest - in the warm season, or ~15 minutes - in cold weather. Against the background of artificial respiration and chest compressions, this time increases to 20-40 minutes.

The only reliably detectable sign of clinical death is the absence of a pulse in the carotid artery. That is, if you approach a “broken” participant and find that there is no pulse in the carotid artery, the participant is dead and you need to immediately begin resuscitation according to the ABC scheme.

Don't waste time determining how your pupils react to light. Firstly, you need to be able to carry out the test correctly, and secondly, on a sunny day you will not be able to determine anything reliably.

Similar do not try to check for breathing using fluff, threads, a mirror, etc. If you find that there is no pulse, begin resuscitation.

In case of biological death, resuscitation is not performed. If signs of biological death appear during resuscitation, resuscitation is stopped.

Among the early reliable signs of biological death, one should check for the presence of cadaveric spots and (sometimes) the “cat's eye” sign.

Cadaveric spots- this is a change in skin color to bluish/dark red/purple-red in those places that face down. For example, on the lower part of the neck, the lower edge of the ears, the back of the head, shoulder blades, lower back, buttocks. Cadaveric spots begin to appear 30-40 minutes after death. With blood loss, as well as in the cold, their appearance slows down, or they may not exist at all. The appearance of cadaveric spots is probably the most reliable and actually detectable early sign of biological death.

"Cat's Eye"- this is a reliable sign of death (if checked correctly), which is determined 30-40 minutes after dying. To check, you need to squeeze hard enough (!) from the sides eyeball of the deceased. In this case, the pupil, which is normally round, becomes oval and does not return to its original shape. This sign should be checked only when it is completely unclear to you whether the person has died or not. Usually it is enough to detect the emerging cadaveric spots.

Reanimation

Resuscitation should be carried out on the most horizontal, level and hard surface possible. Hanging on a wall or in a crack, you will not be able to perform effective resuscitation. Therefore, the first step is to place the participant on a (if possible) flat, hard surface. If resuscitation occurs on a slope, then the victim’s head should be at the level of his feet or slightly lower.

Just before the start of resuscitation, it is necessary to at least approximately determine the mechanism of injury and the cause of death - the caution in handling the person, the ability to move him again, and the decision to administer/not administer any drugs will depend on this.

So, the dead participant lies with his back on the ground, on skis placed under his back, on rocks, on a glacier, on a shelf in a steep slope. The safety of rescuers is ensured.

A- restore patency of the airway by tilting the victim’s head back and raising the neck with your hand. Clean his mouth of saliva, blood, water, snow or any other foreign objects.

IN- start artificial respiration: with the fingers of the hand you press on the forehead, pinch the victim’s nose. Cover your lips with a scarf (if you have one) and take two full, slow exhalations with a pause of 3...5 seconds between them. If you were unable to breathe air into the victim’s lungs due to strong resistance, tilt his head back further before the second breath. If artificial respiration is carried out correctly, then in response to inhalation the victim’s chest rises, and after inhalation a passive “exhalation” occurs.

WITH- Open the victim's chest as much as possible. Usually it is enough to unbutton the down jacket and lift up the thick polar/fleece, but if this is difficult to do, work through a minimum of clothing. Find (feel) a point on the victim’s sternum between its middle and lower third. Place your palm across the sternum, fingers on the left side, and wrist at the found point. Place the second palm across the first, with maximum contact in the wrist area (you can clasp the wrist with the thumb of the “upper” palm). The participant performing the cardiac massage must bend over the victim and apply pressure to the sternum with all his weight. The frequency of pressure is 100 per minute.

Signs of correct performance of chest compressions:

Fingers do not touch ribs.
The arms at the elbows are absolutely straight while pressing.
The sternum is “pressed” 4-5 cm deep.
The second person, placing his fingers on the victim's carotid artery, feels a pulsation in response to your pressure.
It is possible, but not necessarily, that a slight “crunch” will appear during pressing. This is the tearing of the thin tendon fibers running from the ribs to the sternum.

During resuscitation, breaths and compressions on the heart area alternate: one person performs two artificial breaths, then the second makes 30 compressions on the heart area (in about 20 seconds). Once every two minutes, resuscitation is stopped and the pulse in the carotid artery is quickly (5-10 seconds) checked. If there is no pulse, resuscitation is resumed. If there is, monitor the pulse and breathing, administer drugs if necessary (see below), and organize the fastest possible rescues.

During resuscitation, it may be necessary to change the person performing chest compressions. It is difficult to resuscitate, and often people cannot stand it for longer than 10 minutes out of habit. You need to be prepared for this, this is normal.

How long to carry out resuscitation?

During resuscitation, every 2 minutes you need to stop for 10 seconds and check for a pulse and spontaneous breathing in the victim. If they are present, then indirect cardiac massage is stopped, but the pulse and breathing are constantly monitored. If there is a pulse, but spontaneous breathing has not been restored, perform artificial respiration and monitor the pulse.

If resuscitation lasts 30 minutes, and it was not possible to revive the person, resuscitation measures are stopped. Make sure there is no pulse. It is advisable to examine the body for the appearance of cadaveric spots.

The person’s body is laid flat, arms along the body or on the chest. The eyelids are covered. If necessary, the jaw is fixed with a bandage or a roller placed under the chin. If possible, they transport the body themselves, tightly wrapping it in mats. If this is not possible, or living victims are descended on priority, then the body is hidden from the sun's rays and (possible) wild animals, the place is marked with clearly visible markers, and the group goes down for help.

Can drugs be administered during resuscitation?

There are medications that increase the chances of success of resuscitation. And you need to be able to use these drugs in a timely manner.

The most effective drug available is adrenaline. During resuscitation measures, the first aid kit appears at 3...5 minutes of active resuscitation, and if by this moment the heart has not been started, you can inject 1 ml of adrenaline into the soft tissues under the tongue (through the mouth). To do this, the head is thrown back and the mouth is opened (as during artificial respiration), and one ml of adrenaline solution is injected under the victim’s tongue using a 2-ml syringe. Due to the fact that the tongue has a very rich blood supply, part of the adrenaline will reach the heart with venous blood. The only condition is continuous resuscitation measures.

After reviving a person, it makes sense to inject 3 ml of dexamethasone into an accessible muscle (shoulder, buttock, thigh) - this drug will begin to act in 15-20 minutes and will maintain pressure and reduce the severity of cerebral edema in case of injury.

If necessary, after revival, an anesthetic drug is administered: Ketanov 1-2 ml intramuscularly, analgin 2 ml intramuscularly, or Tramadol - 1 ml intramuscularly.

Signs of properly performed resuscitation measures:

After 3-5 minutes of proper resuscitation, the skin color becomes closer to normal.
During chest compressions, the second resuscitator feels the pulsation of the victim’s carotid artery.
While performing artificial respiration, the second resuscitator sees the victim's chest rise in response to inspiration.
Constriction of the pupils: when examining the eyes of the person being resuscitated, the pupils have a diameter of 2-3 mm.

Typical problems and mistakes during resuscitation:

Unable to give artificial breath. Causes: foreign objects in the mouth, or insufficient tilting of the head, or insufficient exhaling efforts.
During artificial respiration, the abdomen swells or the victim begins to vomit. The reason is insufficient tilting of the head and, as a result, inhalation of air into the victim’s stomach.
There is no pulsation in the carotid artery in response to chest compressions. The reason is the incorrect position of the hands on the sternum, or weak pressure on the sternum (for example, when bending the elbows when pressing).
Placing a cushion or an improvised “pillow” under the victim’s head makes independent breathing almost impossible. The cushion can only be placed under the victim’s shoulder blades, so that the head seems to “hang” back a little.
Attempts to find out whether the victim is breathing or not (searching for feathers, threads, mirrors, pieces of glass, etc.) take up precious time. You need to focus mainly on your pulse. Performing artificial respiration on a person who is barely breathing on their own will not cause any harm.

Resuscitation for severe, combined trauma:

The participant has a spinal injury, a broken jaw or other injuries that prevent him from throwing his head back. What to do?

All the same, the ABC algorithm is followed to the maximum extent possible. The head still tilts back, the jaw opens - you just need to do all this as carefully as possible.

The participant has a fractured rib(s) or a rib fracture occurred during cardiac massage.

If one or two ribs are broken, this usually does not lead to any terrible consequences. Indirect massage is carried out in the same way, paying special attention to ensuring that the fingers do not touch the ribs (!). If there are multiple rib fractures, this sharply worsens the prognosis, since the sharp edges of the ribs can damage the lungs (pneumothorax will develop), cut through large arteries (internal bleeding will occur), or damage the heart (cardiac arrest will occur). Resuscitation is carried out as carefully as possible according to the same rules.

The human eye has a complex structure, its components are connected to each other and function according to a single algorithm. Ultimately, they form a picture of the world around us. This complex process works thanks to the functional part of the eye, the basis of which is the pupil. Before or after death, the pupils change their qualitative state, therefore, knowing these features, you can determine how long ago a person died.

Anatomical features of the pupil structure

The pupil looks like a round hole in the central part of the iris. It can change its diameter, adjusting the area of absorption of light rays entering the eye. This opportunity is provided to him by the eye muscles: sphincter and dilator. The sphincter surrounds the pupil, and when it contracts, it narrows. A dilator, on the contrary, expands, connecting not only with the pupillary opening, but also with the iris itself.

The pupillary muscles perform the following functions:

The diametrical size of the pupil is changed under the influence of light and other stimuli entering the retina.
The diameter of the pupillary opening is set depending on the distance at which the image is located.
They converge and diverge on the visual axes of the eyes.

The pupil and surrounding muscles work according to a reflex mechanism that is not associated with mechanical irritation of the eye. Since impulses passing through the nerve endings of the eye are sensitively perceived by the pupil itself, it is capable of reacting to the emotions experienced by a person (fear, anxiety, fright, death). Under the influence of such strong emotional arousal, the pupillary openings dilate. If excitability is low, they narrow.

Causes of narrowing of the pupillary openings

During physical and mental stress, people's eye openings can narrow to ¼ of their usual size, but after rest they quickly recover to their usual levels.

The pupil is very sensitive to certain drugs that affect the cholinergic system, such as cardiac drugs and hypnotics. This is why the pupil temporarily contracts when taking them. There is professional deformation of the pupil in people whose activities involve the use of monocles - jewelers and watchmakers. With eye diseases, such as a corneal ulcer, inflammation of the blood vessels of the eye, drooping eyelid, internal hemorrhage, the pupillary opening also narrows. Such a phenomenon as a cat's pupil at death (Beloglazov's symptom) also occurs through mechanisms inherent in the eyes and muscles around them.

Pupil dilation

Under normal circumstances, enlarged pupils occur in the dark, in low light conditions, with the manifestation of strong emotions: joy, anger, fear, due to the release of hormones, including endorphins, into the blood.

Strong expansion is observed with injuries, drug use and eye diseases. A constantly dilated pupil may indicate intoxication of the body associated with exposure to chemicals and hallucinogens. With traumatic brain injuries, in addition to headaches, the pupillary openings will be unnaturally wide. After taking atropine or scopolamine, temporary dilation may occur - this is a normal side effect. In diabetes mellitus and hyperthyroidism, the phenomenon occurs quite often.

Dilation of the pupils during death is a normal reaction of the body. The same symptom is characteristic of comatose states.

Classification of pupillary reactions

The pupils in a normal physiological state are round and of the same diameter. When the light changes, a reflex expansion or contraction occurs.

Constriction of pupils depending on reaction

What do pupils look like when dying?

The reaction of the pupils to light during death occurs first through the mechanism of field expansion, and then through their narrowing. The pupils of biological death (final) have their own characteristics when compared with the pupils of a living person. One of the criteria for setting up a post-mortem examination is checking the eyes of the deceased.

First of all, one of the signs will be “drying” of the cornea of the eyes, as well as “fading” of the iris. Also, a kind of whitish film is formed on the eyes, called “herring shine” - the pupil becomes cloudy and matte. This occurs because after death, the lacrimal glands, which produce tears that moisturize the eyeball, stop functioning.
In order to fully ensure death, the victim’s eye is gently squeezed between the thumb and forefinger. If the pupil turns into a narrow slit (a symptom of “cat’s eye”), a specific reaction of the pupil to death is stated. Such symptoms are never detected in a living person.

Attention! If the above symptoms were found in the deceased, it means that death occurred no more than 60 minutes ago.

During clinical death, the pupils will be unnaturally wide, without any reaction to lighting. If resuscitation is successful, the victim will begin to pulsate. After death, the cornea, white membranes of the eyes and pupils acquire brownish-yellow stripes called Larche spots. They are formed if the eyes remain slightly open after death and indicate severe drying of the mucous membrane of the eyes.

Pupils at death (clinical or biological) change their characteristics. Therefore, knowing these features, you can accurately state the fact of death or immediately begin rescuing the victim, or rather, cardiopulmonary resuscitation. The popular phrase “The eyes are the reflection of the soul” perfectly describes the human condition. By focusing on the reaction of the pupils, in many situations it is possible to understand what is happening to a person and what actions to take.

Video

The concept and causes of clinical and biological death. Difference, signs.

People live as if the hour of their death will never come. Meanwhile, everything on planet Earth is subject to destruction. Everything that is born will die after a certain period of time.

In medical terminology and practice, there is a gradation of stages of the dying of the body:

predagonia
agony
clinical death
biological death

Let's talk in more detail about the last two conditions, their signs and distinctive features.

The concept of clinical and biological death: definition, signs, causes

photo of resuscitation of people from a state of clinical death

Clinical death is a borderline state between life and biological death, lasting 3-6 minutes. Its main symptoms are the absence of activity of the heart and lungs. In other words, there is no pulse, no breathing process, no signs of body activity.

In medical terms, signs of clinical death are called coma, asystole and apnea.
The reasons that caused its onset are different. The most common are electrical trauma, drowning, reflex cardiac arrest, heavy bleeding, acute poisoning.

Biological death is an irreversible state when all vital processes of the body have ceased and brain cells die. Its symptoms in the first hour are similar to clinical death. However, then they become more pronounced:

herring shine and veil on the iris of the eyes
cadaveric purple spots on the lying part of the body
dynamics of temperature decrease - every hour by a degree
stiffening of the muscles from top to bottom

The causes of biological death are very different - age, cardiac arrest, clinical death without attempts at resuscitation or their late use, injuries incompatible with life received in an accident, poisoning, drowning, falling from a height.

How clinical death differs from biological death: comparison, difference

The doctor makes notes in the card of a patient in a coma

The most important difference between clinical death and biological death is reversibility. That is, a person can be brought back to life from the first state if resuscitation methods are promptly resorted to.
Signs. In clinical death, cadaveric spots on the body, rigor, narrowing of the pupils to “cat-like”, and clouding of the irises do not appear.
Clinical is the death of the heart, and biological is the death of the brain.
Tissues and cells continue to live without oxygen for some time.

How to distinguish clinical death from biological death?

a team of intensive care doctors is ready to return a patient from clinical death

At first glance, it is not always easy for a person far from medicine to determine the stage of dying. For example, spots on the body, similar to cadaveric ones, can form in the person being observed while still alive. The reason is circulatory disorders, vascular diseases.

On the other hand, the absence of pulse and breathing is inherent in both species. Partly it will help to distinguish clinical death from the biological state of the pupils. If, when pressed, they turn into a narrow slit like a cat's eyes, then biological death is evident.

So, we looked at the differences between clinical and biological death, their signs and causes. The main difference and vivid manifestations of both types of dying of the human body have been established.

Video: what is clinical death?

Numerous studies have established that irreversible changes in the body that occur during biological death are preceded by clinical death lasting 3-5 minutes after cardiac and respiratory arrest. Revitalization measures begun at this time can lead to a complete restoration of body functions. Resuscitation methods can be used in any setting, without special equipment. The success of revival depends, first of all, on the time the revival begins, as well as on the strict execution of actions in a certain order.

Signs of biological death are: 1) cadaveric spots (blue-red coloring of parts of the body in sloping places; parts of the body located on top remain light). They appear 30-60 minutes after death; 2) rigor mortis. Starts from the face and hands and moves to the torso and lower limbs,

Clearly expressed 6 hours after death. Relaxation of this state is observed after 24 hours in the same sequence; 3) decomposition - a specific odor, green coloring of the skin, swelling and decay.

Diagnostic signs of clinical death are: lack of breathing, pulse in the carotid and femoral arteries and consciousness; dilation of the pupils and lack of reaction of the pupils to light; cyanotic or gray color of the skin.

Lack of breathing. To find out whether a patient or injured person is breathing, you need to look at the movement of the chest or, by placing your hand on the chest, check whether breathing movements are felt. In case of doubt, it should be assumed that there is no breathing. Shallow and infrequent breathing (5-8 breaths per minute) can also lead to cardiac arrest. With such breathing, it is necessary to begin measures to ensure normal breathing.

Absence of pulse in the carotid and femoral arteries. When breathing and heart stop, the pulse in the arteries disappears. It is easier to determine the pulse on the carotid artery. It should be borne in mind that the person providing first aid can sometimes (especially when nervous) feel his own pulse.

Lack of pupillary response to light. This is the most reliable sign of clinical death. When blood circulation stops and breathing stops, the pupil dilates, occupies almost the entire iris and does not react to light, while in a living person, when the eyes are opened and there is good lighting, the pupils should narrow. In an unconscious state, an unnatural pupil width is a signal of disaster.

Changes in the color of the skin and visible mucous membranes. In a state of clinical death, the skin and mucous membranes acquire a bluish or gray tint. The most pronounced changes in the color of the lips and nail bed.