The critical state in which all the vital systems of an organism die out is called the terminal state preceding biological death. The terminal state is a reversible process, which is characterized by profound metabolic and gas exchange disorders, as well as an emergency drop in blood pressure.
In the process of life, the human body can be in a state of health, illness or in a terminal state, which has its own characteristics. The terminal state is always the result of some kind of trauma or disease, cannot be stopped by the forces of the body and, in the absence of help, leads to death.
The main pathophysiological mechanism is oxygen deficiency in the body (hypoxia), which leads to many compensatory-adaptive and pathological changes.
There are four stages of terminal states:
- Predagonia.
- A terminal pause is a transitional state.
- Agony.
- Clinical death.
Predagonia is an optional stage, which may be completely absent, for example, with cardiac arrest. This condition is characterized by systolic blood pressure of 60 mm Hg and below, tachycardia, which is replaced by bradycardia, respiratory instability (first frequent and deep, then superficial and rare), as well as confusion, inhibition, and seizures. At the beginning of the pre-agony stage, a state of short-term excitement may occur, due to reflex attempts by the body to fight for its life. In addition, there is a lack of excretion of urine by the body (oligoanuria) and a change in the color of visible mucous membranes and skin integuments, which become pale with a cyanotic hue. The duration of the pre-agony stage depends on the capabilities of the body and can range from several minutes to a day.
The transition from pre-agony to agony occurs through the stage of a terminal pause. This stage is characterized by a sudden stop of breathing, accompanied by a slowing of the pulse and even its complete absence, dilated pupils and a sharp inhibition of cardiac activity. The duration of this stage is from several seconds to five minutes.
In the stage of agony, blood pressure is absent, the pulse is felt only on the carotid artery, bradycardia and bradypnea are observed, and consciousness is absent. Usually the agony is short-term, its duration is from several minutes to six hours.
The final stage of the terminal state is clinical death, which is recorded from the moment of complete cessation of cardiac activity and complete respiratory arrest. If within five to seven minutes there is no restoration and stabilization of vital functions, then the death of the cells of the cerebral cortex occurs, and biological death ensues, which excludes the possibility of recovery.
The terminal state requires urgent assistance from the outside. There is a whole range of measures that are used to revive (resuscitate) the patient and remove him from the state of clinical death. The success of these events is more dependent on the time factor.
The state of an organism that is resuscitated after resuscitation is also called terminal (“terminalis” - borderline, referring to the end, lat.), I.e. borderline between life and death. The terminal state of this type has a complex pathophysiological nature, since the combination of reoxygenation and recirculation against the background of deep hypoxic changes in organs and tissues plays the main role in its etiology. The terminal terminal state is characterized by the instability of all life functions due to the complete disorganization of the homeostasis maintenance system during the dying period and the very slow, gradual, insufficiently coordinated restoration of this system after recovery.