Hypertonic, isotonic and hypotonic hyperhydration. Overhydration: causes of pathology, symptoms, treatment Consequences and manifestations

Isotonic overhydration is characterized by an excess of water and solutes at normal plasma osmotic pressure (isotonic excess). With isotonic overhydration, it is mainly the extracellular space that suffers (especially interstitial tissue; see.

Edema diseases

Reasons (Fig. 40)

Rice. 40. Complex of causes of isotonic overhydration.

Excessive administration of saline solutions, usually parenterally, less often enterally, especially in cases of impaired renal function after surgery or injury to an adrenal tumor

Edema diseases

Heart disease with edema

Liver cirrhosis with ascites

Kidney diseases (eg, glomerulonephritis, nephrotic syndrome).

Symptoms (Fig. 41)

Rice. 41. Leading symptoms of isotonic overhydration

It manifests itself as a result of an increase in the extracellular space, especially its interstitial part

Edema formation

Clinically, edema appears only when a larger amount of fluid is retained; doughy edema of the skin; pulmonary edema

swelling of the gastric mucosa

rapid increase in body weight due to the accumulation of fluid ascites

Circulation

Circulatory parameters strongly depend on the underlying disease Pathophysiological data

Since plasma osmotic pressure fluctuates within normal limits, only the extracellular space, especially the interstitial space (“third space”) increases. The saturation of cells with water is normal.

Generalized edema formation can be caused by a number of factors, for example (Mertz):

Hemodynamic influence;

Decrease in colloid osmotic pressure,

Increased capillary permeability,

Hormonal imbalance

Any formation of general edema is accompanied mainly by sodium retention by the kidneys (the influence of aldosterone). In this case, hyperaldosteronism is detected only during the formation of edema, but not in its stable stage.

Secondary aldosteronism causes not only higher sodium reabsorption, but also increased potassium excretion, aggravated by diuretics (see Therapy). This may adversely affect the underlying disease (for example, with cardiac glucoside therapy, etc.).

In the presence of edema, although the body is oversaturated with water, this water is not used directly.

Diagnostics

The history and clinical picture allow us to make a conclusion about organ disorders in which there is a tendency to retain water and sodium. Subsequent swelling indicates overhydration. Plasma osmotic pressure is within normal limits.

A reliable indicator of the beginning accumulation of fluid in the lungs is the PaO2 value.

The first priority is treatment of the underlying disease (for example, heart failure).

Along with this, there are a number of measures with which they try to eliminate edema:

Table 11. Table salt content in various diets

Natural content in regular food without added salt:

3 g table salt/day" 51 mEq sodium

Regular food, but with special unsalted bread:

1 g table salt/day = 17 mEq sodium

Rice-fruit diet:

practically salt-free" 10 mEq/day

Establishing a negative sodium and water balance by limiting the delivery of sodium and water (Table 11). Plasma electrolyte levels should be determined frequently. With very strict restriction of salt in the diet and drug-stimulated natriuresis, sodium deficiency can develop. In this case, the diet needs to be expanded, and sodium even added;

Compensation of protein deficiency (human serum albumin), especially for the treatment of edema in liver cirrhosis, nephrotic or starvation edema;

Stimulation of salts and water with osmodiuretics (infusion solutions of sorbitol and mannitol) and diuretics (Table 12, Fig. 42).

Table 12. Single doses, dosage limits, time of maximum action, duration of action and special side effects of some diuretics (according to Kruck, Leppla, Werning und Siegenthaler)

Rice. 42. Effect of diuretics on the nephron (according to Sherlock).

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Water is a necessary condition for the existence of any living organism. In the human body, its volume on average is 70-80% of the total body weight, with 30% of the total amount located in the intercellular space, and 70% inside the cells.

Violation of this ratio leads to a failure of metabolic processes and the development of serious pathology. In addition, pathogenic microbes and toxins can enter the body with water and cause poisoning. You need to know about this and be able to provide first aid.

Overhydration - what is it?

Let's take a closer look at how you can become poisoned by water. Despite its irreplaceability, water can pose a danger to the body and cause poisoning in the following cases:

In the first case, the cause of poisoning is microbial toxins that are released during the development of corresponding infectious diseases - cholera, typhoid fever, escherichiosis, dysentery. In the second case, pesticides, heavy metal salts, mineral fertilizers and other toxic substances can enter the body. Once in the body, they cause intoxication and damage to internal organs.

Excessive amount of water in the body is called overhydration. It can develop when fluid excretion is impaired due to heart or kidney failure, or due to excessive fluid intake.

And although such cases are called poisoning only figuratively, because it is not associated with toxins, in essence it is true poisoning directly from the water itself, without any other agents, when serious and often life-threatening changes occur in the body.

There are 3 main types of overhydration:

• Extracellular When the amount of fluid in the interstitial space exceeds 30%, this occurs when salts are retained in the body.
• Intracellular when the amount of intracellular water reaches 80% or more, it develops with excessive water consumption.
• General or mixed When excess water in the entire body is the result of excess water intake and insufficient excretion from the body - this is the case when they talk about “water poisoning”.

Symptoms of water poisoning and overhydration

If water intoxication occurs due to the ingestion of microbes, a picture of a corresponding infectious disease develops: nausea, vomiting, diarrhea, increased body temperature.

In case of chemical poisoning, the liver, central nervous system, kidneys are affected, and vision is impaired– depending on the nature of the substance, vomiting is also typical. But in both cases, the body loses fluid through vomiting and diarrhea, resulting in dehydration.

In case of true water poisoning, it accumulates in organs, body cavities, and in the vascular bed. This leads to a decrease in the concentration of electrolytes, the development of cardiac weakness, increased blood pressure, swelling of tissues and organs, including the lungs, brain, and such dangerous symptoms:

• Strong headache.
• Excessive drooling.
• Feelings of heat alternating with chills.
• Nausea, vomiting, diarrhea.
• General lethargy.
• Confusion.
• Dyspnea.
• Cramps.

If help is not provided in a timely manner, pulmonary edema, cerebral edema, convulsions develop, and the patient falls into a coma, which has a high mortality rate.

First aid

In any case, in case of poisoning, you must call an ambulance. If it is associated with infection or chemicals, you need to immediately rinse the stomach, give sorbents, drink plenty of fluids, and cleanse the intestines.

In case of overhydration, these measures are not only ineffective, but can also harm the patient. But you can still provide first aid to alleviate his condition:

• Place in a semi-sitting position to reduce the load on the lungs and brain.
• Provide fresh air flow.

• Give a diuretic to drink.
• Give a tablet of the drug with potassium (panangin, potassium orotate).
• Put cold on your forehead.

If possible, do inhalation through a damp cloth with oxygen from a first aid bottle or pillow. You need to constantly monitor your condition - pulse, blood pressure, and provide a container for urination. All further measures are carried out in such cases only in a hospital setting.

Treatment and recovery

If the poisoning is of an infectious nature, the patient undergoes comprehensive treatment, usually in the infectious diseases department, where antibacterial and detoxification therapy is carried out, replenishment of loss of fluid, salts, vitamins, and normalization of the digestive tract.

Chemical poisoning is treated in toxicology departments, in severe cases - in intensive care units, detoxification of the body and symptomatic treatment are carried out to normalize the functioning of organs.

Overhydration poses a great danger; such patients are hospitalized in the intensive care unit or resuscitation department, with round-the-clock observation and constant monitoring of vital functions, control of water and electrolyte balance.

The level of electrolytes in the blood - sodium, potassium, calcium - is corrected by introducing balanced salt solutions, and diuretics are prescribed to eliminate excess water. Drugs are prescribed to lower blood pressure, improve heart function, stimulate breathing, relieve brain swelling and improve brain function. In case of overload and development of renal failure, hemodialysis is activated.

In the future, a special diet is prescribed to restore the body. with the inclusion of foods containing microelements (seafood, dried apricots, dates, bananas), limiting fluid intake and drinking mineralized water. The body gradually returns to normal if all recommendations are followed.

Consequences and complications

True water poisoning - overhydration is fraught with complications that can cause severe health problems and even death:

The consequences of water poisoning can be tissue swelling, weight gain, the development of hypokalemia and, as a consequence, heart failure. Lack of sodium (hyponatremia) is also a dangerous condition that can lead to a decrease in the excretory function of the kidneys, disruption of the central nervous system, and the development of convulsive syndrome.

What happens if you drink a lot of water?

Promoters of a healthy lifestyle everywhere call for drinking 2-3 liters of water daily to maintain health, and drink it both on an empty stomach and before bedtime. There are also such extreme diets for weight loss, in which it is recommended to only drink a lot of water all day long, without holding “poppy dewdrops” in your mouth.

Such recommendations should be taken critically, especially when it comes to “starvation” diets. Taking an excess amount of water at one time or per day will inevitably lead to the development of overhydration syndrome. The exception is when a person has lost a lot of fluid through sweat. Then you need to drink not plain water, but mineral water, because salts are also lost with sweat.

Medical science has determined the average rate of water consumption per day for a person; it ranges from 2 to 3.5 liters per day, depending on weight.

It is important that this volume includes tea, coffee and other drinks, liquid dishes and juicy fruits. During the hot season, the need for water increases.

Eastern wisdom says: “There is nothing softer in the world than water, but it can destroy even a stone.”

Overhydration is a condition of the body characterized by excess water content in certain parts or throughout the body, and manifested by swelling in the legs, face, ascites, swelling of the brain and lungs. Overhydration is a form of disruption of water-salt metabolism.

This condition develops in the presence of heart, kidney, or liver failure.

Depending on the reasons, there are different types of overhydration.

Treatment of overhydration comes down to treatment of the underlying disease that causes this condition and dehydration therapy.

Causes of overhydration

This condition occurs when more water enters the body than it is able to remove. Its excess content leads to a decrease in sodium levels in the blood.

As a rule, excessive drinking of water does not lead to overhydration if the heart, kidneys, and pituitary gland are working normally.

Most often, the state of overhydration of the body occurs in people with impaired kidney function. Overhydration can occur with congestive heart failure, renal failure, liver cirrhosis, or excess production of antidiuretic hormone by the body.

If, with renal failure, a patient drinks more than three liters of water in an hour, uremic intoxication will develop and he may die from pulmonary edema or cerebral edema.

Therefore, people with the above diseases need to control the intake of water and salt into the body.

Video: Anatomy

Classification and symptoms of overhydration

The following types of overhydration are distinguished:

Video: ATRAUMATIC FACIAL CLEANING LASERHOUSE. Kyiv, KHARKOV, ODESSA, LVIV, Krivoy Rog, DNEPR

• extracellular – interstitial tissue or the entire extracellular space is subject to hydration. Associated with the retention of electrolytes in the body. The main clinical sign of extracellular hyperhydration is edema, which appears with an increase in hydration of more than 5-6 liters. The most dangerous are swelling of internal organs, abdominal edema;
• cellular (intracellular edema) – associated with the accumulation of fluid in the cells. This type of overhydration of the body develops when an excessive volume of water or hypotonic solution is administered. Occurs in nephropathy, which is accompanied by an increase in the effective osmotic pressure of the interstitial fluid and the release of water from the cells. The main symptom of overhydration in this case is thirst and severe weight loss caused by the loss of large amounts of water;
• hyperosmotic or hyperosmolar – associated with an increase in the osmotic pressure of fluids in the body. This condition is associated with the intake of large volumes of saline solutions into the body, especially in combination with the cessation or limitation of the excretion of water and salts by the kidneys, digestive tract, and skin. Symptoms of overhydration in this case are associated with extracellular overhydration (pulmonary edema, cardiac edema, increased cardiac output, circulating blood, blood pressure, central venous pressure, cerebral edema, respiratory failure, neuropsychiatric disorders, thirst) and intracellular hypohydration due to mobilization intracellular fluid (thirst, hypoxia, neuropsychic disorders, general agitation, convulsions, anxiety, which are replaced by the progression of lethargy, decreased reflexes and loss of consciousness with the subsequent development of hyperosmotic coma);
• hypoosmotic or hypoosmolar – associated with a decrease in the osmotic pressure of liquids. This type of overhydration occurs when the intake of water into the body prevails over its excretion (with repeated intake of excess volumes of liquids with a reduced salt content, prolonged consumption of salt-free foods, long-term pathological processes, peritoneal dialysis, infusions of large volumes of glucose). Symptoms of overhydration in this case are associated with a rapid increase in the volume of water in all sectors of the body and are manifested by progressive weight gain, the development and increase of edema, increasing weakness, deterioration of general condition, rapid fatigue, a feeling of weakness. Next, there is the development and intensification of neuropsychic disorders, confusion with subsequent loss of consciousness, convulsions and hypoosmotic coma, which in some cases ends in death;
• general overhydration of the body or “water intoxication - when the entire body is exposed to overhydration. Occurs when an increased intake of water into the body is combined with insufficient excretion. Typically, this is hypoosmotic hyperhydration;
• Normoosmotic or isotonic. It is characterized by a positive water balance with normal osmolality. There is no redistribution of fluid between the extra- and intracellular sectors. This type of hyperhydration is associated with the introduction of large volumes of isotonic solutions into the body, the development of pathologies accompanied by hypoproteinemia (liver failure, nephrotic syndrome), increased permeability of the vascular walls, and the development of blood and lymph circulation failure. Clinical manifestations of isotonic overhydration are: hypervolemia, increased cardiac output, blood volume, blood pressure, peripheral vascular resistance, and later the development of heart failure and edema.

Diagnosis of overhydration

When diagnosing this condition, it is important to establish the type of overhydration, since each of them requires appropriate therapy.

The goal of diagnosis is to determine whether overhydration or increased blood volume is occurring. When overhydration is present, excessive amounts of water are found around and within cells. As blood volume increases, excess sodium is observed and water is unable to move into the intracellular cavity. Distinguishing between increased blood volume and overhydration can be difficult because both processes can occur simultaneously.

To diagnose overhydration, the following are used: ultrasound of the kidneys, intravenous urography, cystography.

Treatment of overhydration

The choice of treatment method depends on the cause that caused the state of overhydration. But in any case, they try to limit the flow of fluid into the body. Drinking no more than one liter of fluid per day improves the patient's condition.

In case of severe overhydration, the patient is prescribed drug treatment, usually with the use of diuretics, which aims to restore water and electrolyte balance. Sometimes symptomatic therapy and hemodialysis are prescribed.

Overhydration is a condition of the body associated with the presence of a certain pathology, which leads to an imbalance in the water balance in the body. The goal of therapy for this condition is to treat the underlying disease and break the links in the pathogenesis of this condition.

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Overhydration

Overhydration is characterized by a positive water balance: the predominance of water intake into the body compared to its excretion and losses. Depending on the osmolality of the extracellular fluid, hypoosmolal, hyperosmolal and isosmolal hyperhydration are distinguished.

Hypoosmolal hyperhydration

Hypoosmolal hyperhydration is characterized by an excess of extracellular fluid in the body with reduced osmolality. Hypoosmolal hyperhydration is characterized by an increase in fluid volume both in the extra- and intracellular sectors, because excess extracellular fluid enters the cells along a gradient of osmotic and oncotic pressure.

Causes

Excessive introduction into the body of fluids with a reduced salt content or lack thereof.

Increased levels of ADH in the blood due to its hyperproduction in the hypothalamus (for example, in the syndrome Parhona).

Renal failure (with a significant decrease in renal excretory function).

Severe circulatory failure with the development of edema.

Consequences and manifestations

Increased blood volume (hypervolemia) and hemodilution.

Hypervolemia and hemodilution are caused by the transport of water into the vascular bed due to the higher osmotic and oncotic pressure of the blood compared to the intercellular fluid.

Polyuria is increased urine output due to increased filtration pressure in the renal corpuscles. Polyuria may be absent at the hypo- or anuric stage of renal failure.

Hemolysis of red blood cells.

The appearance of intracellular components (for example, enzymes and other macromolecules) in the blood plasma due to damage and destruction of cells of various tissues and organs.

Vomiting and diarrhea due to intoxication of the body (due to the release of excess ions, metabolic products, enzymes and other substances from damaged and destroyed cells).

Psycho-neurological disorders: lethargy, apathy, disturbances of consciousness, often convulsions. These disorders are the result of damage to brain cells due to their swelling.

Hypoosmolal syndrome. It develops when the osmolality of blood plasma decreases to 280 mOsm/kg H 2 O and below, usually as a result of hyponatremia (this syndrome can be observed both with hypo- and overhydration of the body).

Reasons for the development of the syndrome

† Hypoaldosteronism, which develops when the production of aldosterone by the adrenal cortex or the sensitivity of the receptors of the kidney tubules to it decreases. In both cases, the level of Na + in the body is reduced.

† Significant loss of sodium by the body (for example, with intense sweating, vomiting, diarrhea).

† Hemodilution with liquids with a reduced (compared to the required) Na + content (for example, with excessive introduction into the body of solutions with a low Na + concentration during detoxification of the body. This is possible in the absence of ongoing monitoring of the ion content and osmolality of the patient’s blood plasma). A drop in blood plasma osmolality below 250 mOsm/kg H 2 O is fraught with the development of irreversible changes in the body and its death.

Hyperosmolal hyperhydration

Hyperosmolal hyperhydration is characterized by increased osmolality of the extracellular fluid, exceeding that in the cells.

Causes

Forced drinking of sea water. It is observed, as a rule, during a long-term absence of fresh water (for example, during disasters on the seas and oceans, when aircraft fall into them).

Introduction into the body of solutions with a high content of salts without monitoring their content in the blood plasma (for example, when carrying out therapeutic measures in patients with iso‑ or hypo-osmolal hypohydration, in case of thyroid hormone replacement disorders).

Hyperaldosteronism, leading to excessive reabsorption of Na + in the kidneys.

Renal failure, accompanied by a decrease in salt excretion (for example, with renal tubulo‑and/or enzymopathies).

These (and some other) reasons cause an increase in the volume and osmolality of extracellular fluid. The latter leads to hypohydration of cells (as a result of the release of fluid from them into the extracellular space along the osmotic pressure gradient). Thus, mixed (associated) dyshydria develops: extracellular hyperhydration and intracellular hypohydration.

Consequences and manifestations

Hypervolemia.

Increase in BCC.

An increase in cardiac output followed by a decrease in the event of heart failure.

Increase in blood pressure.

Increased central venous blood pressure.

All of the above signs of hyperosmolar overhydration are a consequence of an increase in blood plasma volume.

Brain swelling.

Pulmonary edema.

The last two manifestations develop as a result of intracellular hyperhydration, as well as an increase in the volume of intercellular fluid (edema) due to heart failure.

Hypoxia caused by the development of heart failure, circulatory and respiratory disorders.

Neuropsychiatric disorders caused by brain damage due to edema, increasing hypoxia and intoxication of the body.

Severe thirst, developing due to hyperosmolality of blood plasma and hypohydration of cells. Additional intake of water into the body under these conditions aggravates the severity of the patient's condition.

Hyperosmolar syndrome. It is observed when the osmolality of blood plasma increases (most often due to excess Na + and/or glucose) above 300 mOsm/kg H 2 O (both with hyper- and hypohydration of the body). In this case, signs of cell hypohydration are revealed.

The most common causes of the syndrome

† Hyperaldosteronism (both primary, for example, with tumors of the adrenal cortex, and secondary, for example, with renal hypertension, hypokalemia, heart failure).

† Renal failure (for example, against the background of diffuse glomerulonephritis) with impaired excretion of Na +, K + and some others.

† Excessive intake of sodium salts from food.

† Long-term use of mineralo- or glucocorticoids.

† Diabetes mellitus (accompanied by hyperosmia due to hypernatremia and hyperglycemia).

Isoosmolal hyperhydration

Isoosmolal hyperhydration is characterized by an increase in the volume of extracellular fluid with normal osmolality.

Causes

Infusion of large quantities of isotonic solutions (eg, sodium chloride, potassium, sodium bicarbonate).

Circulatory failure, leading to an increase in the volume of extracellular fluid as a result of:

† increase in hemodynamic and filtration pressure in arterioles and precapillaries,

† reducing the efficiency of fluid reabsorption in postcapillaries and venules.

Increasing the permeability of the walls of microvessels, which facilitates the filtration of fluid in precapillary arterioles (for example, during intoxication, some infections, toxicosis of pregnant women).

Hypoproteinemia, in which fluid is transported along an oncotic pressure gradient from the vascular bed into the intercellular space (for example, during general or protein starvation, liver failure, nephrotic syndrome).

Chronic lymphostasis, in which there is inhibition of the outflow of intercellular fluid into the lymphatic vessels.

The mentioned and some other factors cause an increase in the volume of blood volume and intercellular fluid. Developing hyperhydration can be quickly eliminated provided that the water metabolism regulation system is in optimal condition.

Ticket 37.

1. Hyperthermia, types and mechanisms of development, consequences.

2. Ischemia, types, etiology and pathogenesis. Factors determining the consequences of ischemia.

3. Modern ideas about the pathogenesis of extrasystoles. The concept of ectopic rhythms.

4. Types, etiology and pathogenesis of alkalosis. Compensation mechanisms.

2. Ischemia- a phenomenon of local anemia in various organs, caused by narrowing or blockage of the arteries supplying this organ. Long-term I. can lead to necrosis of organ tissue. Ischemia (local anemia) is a condition characterized by reduced blood supply to organs, tissues or their parts.

Ischemia is characterized by the following signs:

1. Reducing the caliber of arterial vessels.

2. Reducing the number of visible arteries, since part of the arterial trunks, due to reduced blood flow, collapses and ceases to function.

3. Pallor of the area of ​​ischemic tissue due to a decrease in the amount of blood in it.

4. Lowering the temperature of the ischemic area due to a decrease in the flow of warm blood and a decrease in the intensity of redox processes in conditions of lack of oxygen (in this case we are talking about superficially located areas of tissue).

5. The occurrence of pain due to irritation of tissue receptors by under-oxidized metabolic products.

6. A slight decrease in the ischemic area in volume, because the amount of blood in it decreases.

For reasons The following types of ischemia are distinguished:

1. Neurogenic, resulting from arterial spasm when the tone of vasoconstrictors becomes higher than the tone of vasodilators.

2. Compression(when the artery is compressed from the outside by a tumor, scar, edema, ligature, etc.).

3. Obstructive(when an artery is closed from the inside by a thrombus, embolus, or atherosclerotic plaque).

4. Redistributive(for example, cerebral ischemia with arterial hyperemia of the mesenteric vessels, with massive bleeding, etc.).

Ischemia is a process that is harmful to organs and tissues, since it disrupts the delivery of nutrients and oxygen, which can ultimately lead to the death of their ischemic areas. However, the outcome of ischemia is not unambiguous, but depends on the degree of development collateral circulation.

Collaterals- these are vascular branches that flow into the same vessel in which they begin. Normally, they do not function, since the blood supply to the organ is carried out through the main vessel, and they open only when the main vessel is closed. The opening of collaterals during ischemia is caused by two factors. Firstly, a pressure difference arises above and below the site of obstruction in the vessel and blood tends to flow to an area of ​​lower pressure, thereby opening the collaterals. In this case, the role of reducing the pressure distal to the place of compression or obstruction plays a role, and not increasing it above this area, since elastic arteries can stretch, which will practically not lead to an increase in the level of pressure above the obstruction. Secondly, in the ischemic area, under-oxidized metabolic products accumulate, which irritate tissue chemoreceptors, resulting in a reflex opening of collaterals.

There are three degrees of severity of collaterals.

1. Absolute sufficiency of collaterals. In this case, the sum of the lumens of the collaterals is either equal to the lumen of the closed artery or exceeds it, and the collaterals open quickly. When the main vessel is closed, blood flow through the collaterals resumes immediately and the amount of blood delivered through them does not decrease. Under these conditions, the state of ischemia is quickly eliminated and no harmful consequences for the body occur.

2. Relative sufficiency (insufficiency) of collaterals. In this case, the sum of the lumens of the collaterals is less than the lumen of the closed artery and (or) the collaterals open slowly. In this situation, blood flow to the ischemic area will either be reduced or normalized not immediately, but some time after the closure of the main vessel. In this case, damage associated with hypoxia will develop in the tissues. The degree of their severity depends on the duration of ischemia and the degree of compensation of blood circulation through collaterals.

3. Absolute insufficiency of collaterals, which is characterized by the fact that the collaterals are poorly expressed and even with full disclosure they are not able to compensate for impaired blood circulation to any significant extent. This poor expression of collaterals is observed, in particular, in the heart and brain. In the case of absolute insufficiency of collaterals, tissue infarction develops with subsequent dysfunction of the corresponding organ.

In case of relative insufficiency of collaterals associated with their slow opening, in the case when during an operation it is necessary to ligate the main vessel (for example, during operations to remove vascular aneurysms or in order to prevent massive bleeding), preliminary training of the collaterals is carried out for several days using special devices, narrowing the lumen of the main artery for some time. The state of mild ischemia that develops in this case, which does not have harmful consequences for the organ, reflexively causes the collaterals to open. After such training, ligation of the main vessel will lead to rapid opening of collaterals and the blood supply to the organ will not be disrupted.

3.1. theory of repeated excitation entry. It is assumed that there is a local blockade of impulse conduction, which causes later excitation of a certain, small area of ​​the myocardium, where the impulse enters in a roundabout way. 2. The theory of increasing the amplitude of trace potentials remaining after the previous excitation. 3. theory of non-simultaneous repolarization of individual myocardial structures. 4. theory of increased automaticity of “latent pacemakers”. 5. theory of parasystoles type. It is assumed that there are ectopic foreign centers that produce impulses at a certain frequency.

4. alkalosis - a violation of CBS, in which there is an excess of bases and a lack of acids. Class: 1. gas, 2. non-gas, 3. excretory.

Metabolic alkalosis - usually occurs as a result of increased acid excretion through the gastrointestinal tract or kidneys. However, the excretion of bicarbonate at its high level in the plasma normally proceeds so quickly that alkalosis will be short-lived - until the reabsorption of bicarbonate increases or alkaline substances begin to form continuously at high speed. In clinical practice, metabolic alkalosis is most often maintained by increasing the process of bicarbonate reabsorption, caused by a reduction in the volume of liquid media or a decrease in the amount of chloride. When the volume of liquid media is reduced, the kidneys inhibit sodium excretion, which prevails over other homeostatic mechanisms, for example, the mechanism aimed at correcting alkalosis. Since during alkalosis most of the plasma sodium ions are combined with bicarbonate, complete reabsorption of sodium filtered in the glomeruli entails the reabsorption of bicarbonate. Alkalosis continues until the decrease in the volume of liquid media is eliminated by introducing a sodium chloride solution. This reduces the renal tubular appetite for sodium and chloride becomes an alternative ion for reabsorption along with sodium. Subsequently, excess bicarbonate can be excreted with sodium.

Respiratory alkalosis is a consequence of hyperventilation due to traumatic brain injury, fever, pain syndrome, hyperammonemia, anemia, infection (encephalitis, sepsis, pneumonia, etc.), transient thyrotoxicosis, irrationally performed mechanical ventilation (although sometimes this is a conscious decision of the doctor - as a therapeutic measure). Pathogenesis. During respiratory alkalosis, sodium or potassium bicarbonate accumulates in the cells, hydrogen ions are lost, which somewhat compensates for the increase in the pH of the extracellular fluid and slightly reduces the concentration of plasma bicarbonate. The main mechanism of compensatory decrease in plasma bicarbonate during respiratory alkalosis is a weakening of bicarbonate reabsorption by the kidneys.

TICKET No. 38

1. Outcomes of the disease. The outcomes of the disease can be, depending on the severity and nature of the disease, as well as on the reserve capabilities of the body and the effectiveness of therapeutic measures and means, very different, in particular, the following:

Recovery (convalescence) is the restoration of normal functioning of the body. It can be complete (with complete restoration of structure, metabolism and functions) and incomplete, or partial (with incomplete restoration of structure, metabolism and functions), - transition to another disease, - transition to a pathological state, - transition to a pathological process, - death (death), which is first clinical (represents a terminal condition, still reversible with timely qualified medical care), and then biological (irreversible cessation of the vital activity of the organism as a whole). Recovery is the restoration of the impaired functions of a sick organism, its adaptation to existence in the environment and (for a person) a return to work. In this sense, recovery is called rehabilitation (from the Latin re - again and abilitas - fitness). This means both the return of a recovered person to his previous work activity, and his retraining in connection with a change in the state (new quality) of health. With complete recovery, no traces of the disorders that were present during the illness remain in the body. With incomplete recovery, dysfunctions of individual organs and their regulation persist to varying degrees of severity. One of the expressions of incomplete recovery is a relapse (return) of the disease, as well as its transition to a chronic state.

2. Violation of mineral metabolism. Minerals participate in the construction of structural elements of cells and tissues and are part of enzymes, hormones, vitamins, pigments, and protein complexes. They are biocatalysts, participate in many metabolic processes, play an important role in maintaining the acid-base state and largely determine the normal functioning of the body. Causes of disturbances in mineral metabolism in the body: - living in large cities, - busy life, stress, - exposure to unfavorable environmental factors, - unhealthy diet, frequent “diets”, - nervousness, - smoking, - alcohol abuse, etc.

Chronic imbalance of essential microelements leads to serious changes in body functions (deviations in the metabolism of proteins, fats, carbohydrates, vitamins and the production of enzymes, weakened immunity, failure of the endocrine and nervous systems) and causes neuropsychiatric disorders, cancer, inflammatory damage to organs and tissues.

Consequences of mineral metabolism disorders. Deficiency of microelements is observed primarily in children and adolescents during periods of intensive growth, in pregnant women and during feeding, in people with increased emotional and physical stress, in people prone to frequent colds, etc.

Calcium is associated with the processes of cell membrane permeability. Excitability of neuromuscular devices, blood coagulation, regulation of acid-base status, skeletal formation, etc. Disorders of calcium metabolism are called calcinosis. It is based on the precipitation of calcium salts from a dissolved state and their deposition in cells or intercellular substance. The matrix of calcification can be mitochondria and lysosomes of cells, glycosaminoglycans of the main substance, collagen or elastic fibers. In connection with these, intracellular and extracellular calcification are distinguished. Calcification may be systemic or local. Depending on the predominance of general or local factors in the development of cadcinosis, there are three forms of calcification: metastatic, dystrophic and metabolic. Metastatic calcification (calcareous metastases) are widespread. The main cause of its occurrence is hypercalcemia, associated with increased release of calcium salts from the depot, reduced excretion from the body, and disruption of the endocrine regulation of calcium metabolism. The occurrence of calcareous metastases is noted with the destruction of bones, osteomalacia and hyperparathyroid osteodystrophy, lesions of the colon and kidneys, excessive administration of vitamin D to the body, etc.

There are systemic and limited calcinosis. With interstitial systemic calcinosis, lime deposits in the skin, subcutaneous tissue, along the tendons, fascia and aponeuroses. In muscles, nerves and blood vessels; sometimes the localization of deposits is the same as with calcareous metastases.

Interstitial limited calcification, or calcareous gout, is characterized by the deposition of lime in the form of plates in the skin of the fingers, less often the feet.

The meaning of calcium metabolism disorders. The prevalence, localization and nature of calcifications matter. Thus, the deposition of lime in the vessel wall leads to functional disorders and can cause a number of complications. The deposition of lime in a caseous tuberculosis lesion indicates its healing, i.e., it is reparative in nature. Disorders of copper metabolism are most clearly manifested in Wilson's disease. With this disease, the excretion of copper into the bile is impaired, which leads to an increase in the copper content in the body with its accumulation in the cells. Copper deposition in hepatocytes is due to reduced formation of ceruloplasmin in the liver, which is capable of binding copper in the blood. The liver and basal ganglia of the brain are the most frequently damaged tissues, therefore Wilson's disease is also called hepato-cerebral dystrophy. An increase in the amount of potassium in the blood (hyperkalemia) and in tissues is observed in Addison's disease and is associated with damage to the adrenal cortex, the hormones of which control the balance of electrolytes. In some adrenal adenomas, hypokalemia may also be observed (aldosteroma with the development of Conn's syndrome). Potassium deficiency underlies a hereditary disease called periodic paralysis. The disease is accompanied by attacks of weakness and the development of motor paralysis

3. Violations of selective and generalized absorption of nutrients in the intestine. Digestive disorders in the intestine are caused by a violation of its main functions: digestive, absorption, motor and barrier-protective.

Overhydration- a phenomenon opposite to dehydration - if during dehydration the body loses water, then during overhydration the body becomes oversaturated with water.

Isotonic hyperhydration

With isotonic overhydration, an increase in the volume of interstitial fluid occurs against the background of a proportional retention of sodium and water in the body, while the osmotic pressure of the plasma does not change.

Causes of isotonic overhydration:

• chronic heart failure;
• toxicosis of pregnancy;
• excessive administration of isotonic saline solutions;
• cirrhosis of the liver;
• kidney diseases.

Clinical manifestations of isotonic overhydration:

• arterial hypertension;
• rapid increase in body weight;
• development of edematous syndrome;
• decrease in blood concentration parameters.

Treatment of isotonic overhydration consists of targeted action on the pathogenic factor, as well as the use of treatment methods aimed at reducing the volume of interstitial space (intravenous 10% albumin, diuretics). In extreme cases, hemodialysis with blood ultrafiltration.

Hypotonic overhydration

With hypotonic overhydration, or water poisoning (plasma sodium less than 130 mmol/l), a decrease in plasma osmolarity occurs, as a result of which water enters the cells, causing the appearance of neurological symptoms.

Causes of hypotonic overhydration:

• simultaneous intake of large quantities of water (10 liters or more);
• long-term intravenous administration of salt-free solutions;
• swelling due to chronic heart failure;
• liver cirrhosis, acute renal failure, overproduction of antidiuretic hormone.

Clinical manifestations of hypotonic overhydration:

• vomiting, frequent loose, watery stools;
• damage to the central nervous system: weakness, weakness, fatigue, sleep disturbance, delirium, disturbances of consciousness, convulsions, coma.

Treatment of hypotonic overhydration consists of targeted action on the pathogenic factor, as well as the fastest possible removal of excess water from the body. Diuretics are prescribed, and in extreme cases, hemodialysis with ultrafiltration of blood.

Hypertensive overhydration

With hypertensive overhydration (plasma sodium more than 150 mmol/l), the osmolarity of the fluid in the interstitial space increases, followed by dehydration of the cellular sector and increased release of potassium from it.

Causes of hypertensive overhydration:

• introduction of large quantities of hypertonic solutions into the body with preserved renal excretory function;
• administering large quantities of isotonic solutions to patients with impaired renal excretory function.

Clinical manifestations of hypertensive overhydration:

• thirst;
• skin redness;
• increased body temperature;
• increased blood pressure and central venous pressure;
• As the disease progresses, signs of central nervous system damage are observed: mental disorders, convulsions, coma.

Treatment of hypertensive overhydration consists of targeted action on the pathogenic factor, the use of infusion therapy with the replacement of saline solutions with native proteins and glucose solutions, as well as the use of osmodiuretics and saluretics. In extreme cases, hemodialysis.

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