Extreme condition



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EXTREME CONDITION

During the life of a person can be exposed to various exogenous and endogenous factors of extreme force, duration and / or unusual, unusual character. The action of extreme factors leading to the development of an emergency or to adapt to this factor, or extreme, critical, urgent status.

Urgent adaptation is characterized by limiting the body's stress adaptation mechanisms that prevents the shift of the most important parameters and constants of its life beyond the normal range. The content of the state of emergency is the first stage adaptation of the adaptation process. Upon termination of the emergency factor, eliminate or compensate for its effects to normal body condition.

Extreme, critical, urgent condition characterized by significant impairment of vital activity, in spite of the limit activation mechanisms of adaptation. Independent exit the body of such a state, as a rule, is not possible. In such cases it is necessary to provide timely and effective medical care.


EXTREME and terminal states

Extreme conditions - severe general condition of the body, developing under the influence of extreme factors of the external or internal environment characterized by significant disturbances of vital activity, fraught with death.

Extreme conditions occur, as a rule, limiting the activation and subsequent depletion of coping mechanisms, rude disorders of functions of organs and physiological systems.

Extreme conditions require emergency medical care.

The most common and clinically important urgent conditions include collapse, shock, coma and poisoning.

From extreme is necessary to distinguish the terminal state, which represent the final stages of life of the organism, the borderline state between life and death.

terminal states

By the terminal states include all the stages of dying - preagonia, agonia, clinical death, as well as the initial stage of the state after a successful resuscitation.

Terminal states are usually the result of unfavorable course of extreme conditions. If the terminal is not able to carry out intensive medical measures or they are ineffective, it comes, and then the clinical - biological death.

The pathogenic factor → Extreme condition → terminal condition → Clinical Death → biological death

Extreme and terminal condition have both similar and radically distinguish their features.

The similarity of extreme and terminal states

Extreme and terminal states have a number of common features:

- Common causes.

- Similar key pathogenesis.

- Borderline situation between life and death.

- Lead to the death of the organism.

- Require urgent medical care.

Although there were similarities, the two states are qualitatively different groups from each other.

Differences extreme and terminal states



criteria

Extreme state

Terminal state

Intensity of the specificity of the causal factor

Increase

Low or absent

The specificity of pathogenesis links

Increase

Low or absent

The effectiveness of adaptation

Increase

Low

reversibility

High: spontaneous, under the influence of treatment

Spontaneously usually impossible; in the treatment of relatively low

Effectiveness of treatment

Increase

relatively low

At the heart of the terminal states are much more severe and therefore prognostically unfavorable processes. If not carried out emergency remedial measures, the terminal state of becoming progressive, irreversible flow, leading to death. In contrast, under certain extreme conditions (collapse, and sometimes - in the early stages of shock) can activate the processes of adaptation, reducing the degree of deviation of homeostasis parameters, improving the body's ability to live in and out of these states.

When development terminal state gradually lost its importance of nature caused the causal factor. Pathogenic effects of his actions are so great that the specific reasons for the state of the terminal loses its meaning.

Specificity is low and terminal states of development mechanisms. When different types of these states key links of their pathogenesis are hypoxia, abnormalities of acid-base balance, blood gases, toxemia, and others. In contrast, under extreme conditions identified as the specifics of the calling their agent, and especially their development mechanisms. In this regard, for specific causal and pathogenetic therapy of extreme conditions can block their development and normalize the functioning of the organism.


General etiology of extreme conditions

Extreme factors different from other pathogenic agents that provide the data and the specific conditions under the action of the body is very high, very intense, often devastating effect.


Types of extreme factors.

Extreme factors are divided into exogenous and endogenous.

1. extreme exogenous factors may be physical, chemical or biological nature.

- Factors of the physical nature: mechanical, electrical, thermal, barometric, radiation, gravity.

- Chemical factors: limiting the deficit / surplus of oxygen, metabolic substrates, liquid; expressed intoxication of drugs, industrial poisons, acids, alkalis.

- Biological factors: significant deficit / surplus of exogenous bioactive substances; bacteria, parasites and fungi (toxins, metabolic products thereof, and / or decay).

2. Endogenous (adverse, severe course of disease and disease states).

- Severe impairment of functions of organs and physiological systems.

- A significant blood loss.

- Massive bleeding in the organs.

- Excess food or allergic immune responses.

- A significant deficiency / excess of BAS and / or their effects.

- Mental surge injury.

Conditions that contribute to extreme conditions.

1. Factors potentiating effects extreme agents.

For example, the state of sensitizing the body can lead to a more severe course of anaphylactic shock by the action of the allergen, the effects of blood loss are compounded at elevated temperature, heart failure when performing excessive exercise can lead to cardiogenic shock, etc.

2. The reactivity of the organism.

Often it is a decisive condition for the action of extreme factors. Unlike normergic response hypo - or hyperergic condition of the body facilitates the occurrence, course and outcomes exacerbating extreme condition.


Pathogenesis of extreme conditions

Extreme conditions are characterized, as a rule, dynamic stage development. In most cases (except for acute and quickly developing situations caused by extreme superstrong factors leading to rapid death of the body) in the dynamics of increasing severity of extreme conditions can be divided into three stages: the activation of adaptive mechanisms, exhaustion and lack of them, extreme regulation of the body's vital functions.


Stages of extreme conditions.

Stage 1: Activation of adaptive mechanisms

The reason - the alarm action:

1) damaging factor,

2) deviations of the parameters of homeostasis



Stage 2: Failure of adaptive mechanisms

Causes:


1) increase the degree and extent of damage of the organism,

2) stress and exhaustion of adaptive processes



Stage 3: Extreme regulation of vital activity

Causes:


1) a further increase in the extent and scale of the body damage,

2) progressive failure of adaptive mechanisms.


Stage activation of adaptive mechanisms of the organism

This stage is characterized by a generalized activation of the legitimate functions of tissues, organs and systems. This is the basis of development of adaptive reactions of varying degrees of severity and specificity. Essentially all of these reactions can be divided into two categories:

- Providing specific adaptation to the particular extreme factors;

- Implement the non-specific, standard processes, developing under the influence of any extreme effects, ie stress reaction.


Stage failure of adaptive mechanisms

The main feature of this stage: the lack of efficiency of adaptive responses and growth of the damaging effect of extreme agent.



1. Pathogenesis

- Increasing the efficiency of reduction reaction devices, compensation, protection and reparation.

- Progressive disorder of the physiological functions and the collapse of the functional systems of the body.

- Metabolic disorders and physical-chemical processes.

- Damage to the structural elements of organs, tissues and cells

- Braking plastic processes them.

As a result of these changes most homeostasis parameters deviates beyond the normal range, and often significantly. Vital functions of the whole organism is disturbed significantly.

2. Vicious circles

With all the extreme states, albeit with a different frequency, can form a vicious circle. This phenomenon lies in the fact that an initial pathogenetic factor causes a closed complex by increasing the degree of violation. Consequences of them, in turn, potentiate the action of an initial pathogenic factor based on positive feedback.

- Education pathogenetic vicious circle leads to growth disorders in the body, "weighting" extreme conditions up to move it to the terminal, even in the termination of extreme factors.

examples:

- During the collapse, shock and coma observed blood flow redistribution. A large amount of blood is collected in the extended venous and arterial vessels of the abdomen, lungs, subcutaneous tissue. This significantly reduces the bcc and hence the blood flow to the heart. The consequent decrease in cardiac ejection of blood leads to an even greater decrease in VCB and exacerbate the patient's condition.

- Activation phenomenon lipoperoxide processes in tissues. Hypoxia, growing in all types of extreme conditions, results in the suppression of the activity of non-enzymatic and enzymatic antioxidant defense system tissue. This leads to intensification of education in which reactive oxygen species and lipoperoxide processes that damage the enzymes of tissue respiration, glycolysis, the pentose phosphate shunt. The latter is even more aggravated hypoxia - a vicious circle and potentiating its development.

In general, at the stage of failure of adaptation mechanisms in various extreme states is developing a set of regular stereotypical interrelated changes in the body. For chief among them are the characteristic triad of disorders.

- Frustration and lack of functions of organs and physiological systems: the neuro-humoral, respiratory, cardiovascular, blood, hemostasis, and others.

- Significant abnormalities of homeostasis parameters, including essential and critical.

- Damage to the subcellular structures, cells and disruption of intercellular interaction.

Manifestations.

1. Disorders of the nervous system. They are characterized by different degrees of sensitivity and character disorders, motion control, integration of activity of bodies, tissues and systems, VNS.

- In the collapse (due to significant violations of perfusion of organs, including the brain) develops a condition characterized by indifference to events, the oppressed and the deep anguish.

- When shock conditions (in the braking phase) showed a significant inhibition, detachment, "leaving a" loss of contact with others.

- In a coma consciousness violated. First, there is confusion and drowsiness, and soon - loss of consciousness, combined with hyporeflexia. At the same time revealed significant disorders of blood circulation, breathing and other vital functions. The latter is a result of integrating function disorder of the nervous system.

2. Violation of the CVS activities. Manifested arrhythmias and signs of coronary heart disease, various disorders of the central, organ, and microcirculation. This leads to the development of capillarotrophic failure in various organs. This in turn potentiates the failure of their functions - heart, kidneys, liver, lungs, and others.

3. Variations in the blood system and hemostasis. Causes a violation of the volume, viscosity and flow of blood; forming units of its formed elements, the phenomenon of sludge, blood clots. A frequent consequence of hemostasis disorders are trombohemorragic state, often leading to death of the organism.

4. Disorders of external respiration. Exacerbate extreme conditions due to the potentiation of hypoxemia, hypercapnia and hypoxia. At the stage of failure of adaptation mechanisms, tend to develop so-called periodic breathing forms (Biota, Cheyne-Stokes, Kussmaul), while during heavy - its complete cessation - apnea.

5. The lack of kidney function. It appears oligo - or anuria, filtration disorder, excretion, secretion and other processes in them. This often leads to varying degrees of severity of uremia.

6. Violation of the liver. Causes the disorder of protein, carbohydrate and lipid metabolism, metabolism of bile pigments, the inactivation process of toxic metabolic products, potentiates hemostatic disorders. At the duration of the current extreme conditions (eg, coma), severe liver failure can significantly speed up the transition to the terminal.

7. Disorders of the functions of the digestive tract. Develop, as a rule, in case of severe during these extreme conditions such as shock and coma. They manifest violations of the secretory and motor functions of the stomach and intestines (until his paresis), cavity and membrane digestion. Therefore patients often develop autoinfection intestinal syndromes, auto-intoxication and malabsorption.

8. Significant deviations from the normal range of homeostasis parameters. It is a natural manifestation of the failure of functions of organs and systems. The most significant variations:

a) Reduction of the partial voltage and the oxygen content in the blood. This indicates the development of hypoxia, which is on the rise as well as severity of the condition progresses.

- Hypoxia in almost all varieties of extreme conditions plays a very important, and in many cases - a major pathogenic role, being one of the key and obligatory links of their pathogenesis.

- The origin of hypoxia, is usually mixed. It is caused by disorders of the central, organ, tissue and microcirculation, external and tissue breathing process of oxygenation of hemoglobin in the lungs and its dissociation in the tissues, as well as deficiency of substrate oxidation.

- During the development of the state of extreme hypoxia causes or potentiating factor cascade of disorders defined by it: acidosis, the intensification of the processes of generation of reactive oxygen species and lipoxide, imbalance and other ions.

b) Reduction of the pH of blood plasma and other biological fluids (acidosis development). Acidosis may be a gas (respiratory) and non-gas (metabolic and excretory).

c) Abnormal content of different ions. The breakdown of biological oxidation in the tissues and as a result - their energy and acidosis cause a violation of physico-chemical state of cell membranes and enzymes. This leads to the intracellular accumulation. Na +, Ca2 + and other ions exit the cell K +, Mg2 +, H +, trace elements. Therefore the optimal ratio of the ions is disturbed between cells and body fluids. Excess hydrophilic Na + in cells causes their overhydration, swelling and, frequently, the membranes rupture.

d) Changes in the value of the MP and PD characteristics of the surface charge of cells, their colloidal state plasmolemma and cytosol, the osmotic pressure of blood plasma.

9. Changes in the body at the stage of failure of adaptation and reaction mechanisms of extreme conditions may differ significantly for different kinds of (collapse, shock, coma) and even with the same form, but in different patients. The reason is that the original disorder functions, metabolism, plastic processes and structures cause a cascade of secondary violations.


Stage extreme regulation of vital activity

The main characteristics of the stage of extreme regulation of the body's vital functions.

Hypo - and deafferentation:

- Central nervous structures,

- Organs and tissues.

Lack of functions and the collapse of the physiological and functional systems



Minimization:

- The functions of organs and tissues,

- Energy expenses,

- Plastic processes.

Metabolic regulation of the functions of organs and tissues



The terminal condition


The reasons: the growth of the degree and extent of damage to the body, progressive failure of adaptation mechanisms.

Pathogenesis

Key pathogenesis:

- Increasing (with a significant energy shortage, acidosis, disorders of the ion balance and other changes in the body), hypo - and deafferentation of the central and peripheral nervous structures, as well as the executive organs and tissues.

- The collapse of functional systems that maintain the body's vital parameters.

- The transition to elementary - level metabolic regulation of vital functions of organs and tissues.

With an increase of these changes is developing a terminal condition and death occurs. However, holding on extreme control stage effective treatment can block the progression of the disorder, restore and even normalize the condition of the victim.
PRINCIPLES OF TREATMENT OF EXTREME CONDITIONS

Immediate therapeutic measures when extreme conditions are based on the implementation of the four basic principles: etiotrop, pathogenetic, and symptomatic sanogenetic.


Etiological treatment

Causal treatment is designed to stop or decrease the strength and scale of pathogenic action adventure agent. This is achieved by different methods depending on the type of emergency conditions.

For example:

- Stop the bleeding;

- Termination of the low or high temperature;

- Normalization of the oxygen content in the inspired air;

- Elimination of failure, organ function, hormone deficiency or their effects;

- The use of antitoxic means.


Pathogenetic treatment

Pathogenetic therapy aims to block the development of mechanisms for extreme conditions. This objective is usually achieved by acting on the key or key binding pathogenesis. These include circulatory disorders, respiratory depression, hypoxia development, shifts AAR, ion imbalance, activation processes lipoxigenic and others.


Sanogenetic therapy

Sanogenetic therapy aims to activate and / or potentiation of defense mechanisms, compensation, adaptation and compensation for lost or damaged structures and functions of the body. Ensured by stimulation of the heart function, respiratory, kidney, liver and other organs and tissues; activation of repair processes of detoxification systems, the elimination of excess oxygen radicals and lipid; potentiation of plastic and other reactions.


Symptomatic treatment

Symptomatic therapy involves the removal of unpleasant, painful, aggravating the condition of the patients symptoms and sensations: headaches, fear of death, causalgia, hypo- or hypertensive reactions and others.

In addition to the implementation of the general principles of the above-described treatment of extreme conditions, in each patient carried a set of individual measures, taking into account the specific characteristics of extreme exposure, especially to respond to him of the victim, the dynamics of life and severity of disorders, moreover, a particular version of an extreme condition.
Collapse

Collapse - general, developing acute condition that occurs as a result of significant discrepancies bcc capacity of the vascular bed. It is characterized by circulatory failure, the primary circulatory hypoxia, a disorder of functions of tissues, organs and systems.




Species origin collapse

Cardiogenic

Hypovolemic

vasodilatory

- Myocardial

- posthemorrhagic

- hyperthermal

- Arrhythmic

- dehydration

- toxic

- cardiomiopathic

- toxic and infectious

- orthostatic

- orthostatic


ETIOLOGY

The immediate cause of the collapse is a rapidly developing significant excess capacity of the vascular bed in comparison with VCB.

The reasons for the collapse of

1. By reducing the value of blood ejected from the heart ventricles in the vascular bed develops cardiogenic collapse. This occurs when:

- Acute heart failure (caused by ischemia and myocardial infarction, significant Brady - or tachycardia);

- Conditions that impede the flow of blood to the heart (with stenosis of the valve hole, embolism or vascular stenosis of the pulmonary artery system);

- There are obstacles to eject blood from the left ventricle (the most common in stenosis of the valve opening of the aorta).

2. When reducing the BCC develops hypovolemic collapse. By this result:

- Acute massive bleeding;

- Rapid and significant dehydration (with profuse diarrhea, poisoning, sweating, uncontrollable vomiting);

- The loss of a large volume of blood plasma (for example, extensive burns);

- Redistribution of blood from the deposit large amounts of it in the venous blood vessels, blood capillaries and sinuses (eg, in shock, gravitational overloads, some intoxication).

3. By reducing the total peripheral vascular resistance develops vasodilatory collapse. This can occur in severe infections, intoxication, hyperthermia, endocrinopathy (with hypothyroid conditions, acute and chronic adrenal insufficiency), incorrect use of drugs (eg, sympatholitic, ganglioblockage, drugs, calcium channel blockers), hypocapnia, blood excess adenosine, histamine, kinins, profound hypoxia and a number of others.
Risk factors

Collapse development is largely dependent on a number of specific conditions (risk factors):

- Physical characteristics of the environment (low or high temperature, level barometric pressure, humidity);

- The state of the body (the presence or absence of a disease, pathological process, psycho-emotional status, etc.).

These and other conditions can both promote and impede the emergence collaptoid nature, as well as a significant effect on the severity of its course and outcome.




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