APPENDIX 3

METHODOLOGICAL DEVELOPMENT FOR TEACHERS AND STUDENTS

TO THE TOPIC "GENERAL EXAMINATION OF THE PATIENT"

Criteria for assessing the general condition

2. Indications for emergency hospitalization, as well as the urgency and scope of therapeutic measures.

3. Nearest forecast.

The severity of the condition is determined by a complete examination of the patient.

1. during questioning and general examination (complaints, consciousness, position, skin color, swelling ...);

2. when examining systems (respiratory rate, heart rate, blood pressure, ascites, bronchial breathing or the absence of breath sounds over the lung area ...);

3. after additional methods (blasts in the blood test and thrombocytopenia, heart attack on the ECG, bleeding stomach ulcer on FGDS ...).

There are: a satisfactory condition, a moderate condition, a serious condition and an extremely serious condition.

Satisfactory condition

Functions are vital important organs compensated.

No need for emergency hospitalization.

There is no threat to life.

Does not need care (care for a patient due to functional insufficiency of the musculoskeletal system is not the basis for determining the severity of the condition).

A satisfactory condition occurs in many chronic diseases with relative compensation of vital organs and systems (clear consciousness, active position, normal or subfebrile temperature, no hemodynamic disturbances ...), or with a stable loss of function from the cardiovascular system, respiratory system, liver, kidneys, musculoskeletal system , nervous system but without progression, or with a tumor, but without significant dysfunction of organs and systems.

Wherein:

The functions of vital organs are compensated,

There is no immediate adverse prognosis for life,

There is no need for urgent therapeutic measures (receives planned therapy),

The patient serves himself (although there may be a limitation due to the pathology of the musculoskeletal system and diseases of the nervous system).

Moderate condition

2. There is a need for urgent hospitalization and medical measures.

3. There is no immediate threat to life, but there is a possibility of progression and development of life-threatening complications.

4. Motor activity is often limited (active position in bed, forced), but they can serve themselves.

Examples of symptoms detected in a patient with a moderate condition:

Complaints: intense pain, severe weakness, shortness of breath, dizziness;

Objectively: consciousness is clear or stunned, high fever, pronounced edema, cyanosis, hemorrhagic rashes, bright jaundice, HR over 100 or under 40, HR over 20, impaired bronchial patency, local peritonitis, repeated vomiting, severe diarrhea, moderate intestinal bleeding, ascites ;

Additionally: heart attack on the ECG, high transaminases, blasts and thrombocytopenia less than 30 thousand / µl in an. blood (may be a state of moderate severity even without clinical manifestations).

serious condition

1. Decompensation of the functions of vital organs and systems.

2. There is a need for emergency hospitalization and therapeutic measures (treatment in an intensive care unit).

3. There is an immediate threat to life.

4. Motor activity is often limited (active position in bed, forced, passive), they cannot take care of themselves, they need care.

Examples of symptoms seen in a severely ill patient:

Complaints: unbearable prolonged pain in the heart or abdomen, severe shortness of breath, severe weakness;

Objectively: consciousness may be impaired (depression, agitation), anasarca, severe pallor or diffuse cyanosis, high fever or hypothermia, thready pulse, severe arterial hypertension or hypotension, shortness of breath over 40, prolonged attack of bronchial asthma, incipient pulmonary edema, indomitable vomiting, diffuse peritonitis, massive bleeding.

Extremely serious condition

1. Severe decompensation of the functions of vital organs and systems

2. There is a need for urgent and intensive therapeutic measures (in intensive care)

3. There is an immediate threat to life in the next minutes or hours

4. Motor activity is significantly limited (the position is often passive)

Examples of symptoms seen in a critically ill patient:

- Objectively: the face is deathly pale, with pointed features, cold sweat, pulse and blood pressure are barely detectable, heart sounds are barely audible, respiratory rate up to 60, alveolar pulmonary edema, "silent lung", pathological Kussmaul or Cheyne-Stokes breathing ...

State examples

It is based on 4 criteria (in the rationale for the examples are indicated by numbers):

1. Decompensation of the functions of vital organs and systems (respiratory, CCC).

2. Indications for emergency hospitalization, as well as the urgency and volume of treatment

events.

3. Forecast.

4. Motor activity and the need for care.

Bilateral coxarthrosis III–IVst. FN 3.

Satisfactory condition (care of the patient due to functional insufficiency of the musculoskeletal system is not the basis for determining the severity of the condition).

Bronchial asthma, attacks 4-5 times a day, stops on its own, dry rales in the lungs.

Satisfactory condition.

Iron deficiency anemia, Hb100g/l.

Satisfactory condition.

IHD: stable angina. Extrasystole. NK II.

Satisfactory condition.

Diabetes mellitus with angiopathy and neuropathy, sugar 13 mmol/L, consciousness is not disturbed, hemodynamics is satisfactory.

Satisfactory condition.

Hypertonic disease. BP 200/100 mmHg But not a crisis. BP decreases with outpatient treatment.

Satisfactory condition.

Acute myocardial infarction without hemodynamic disturbances, according to ECT: ST above the isoline.

Condition of moderate severity (2.3).

Myocardial infarction, without hemodynamic disturbances, subacute period, according to ECG: ST on the isoline.

Satisfactory condition.

Myocardial infarction, subacute period, according to ECG: ST on the isoline, with normal blood pressure, but with a violation of the rhythm.

Moderate condition (2, 3)

Pneumonia, volume - segment, good health, subfebrile temperature, weakness, cough. There is no shortness of breath at rest.

Condition of moderate severity (2, 3).

Pneumonia, volume-lobe, fever, dyspnea at rest. The patient prefers to lie down.

Condition of moderate severity (1,2,4).

Pneumonia, volume - a fraction or more, fever, tachypnea 36 per minute, decreased blood pressure, tachycardia.

The condition is severe (1,2,3,4).

Cirrhosis of the liver. Feeling good. Enlargement of the liver, spleen. No ascites or slight ascites on ultrasound.

Satisfactory condition.

Cirrhosis of the liver. Hepatic encephalopathy, ascites, hypersplenism. The patient walks, serves himself.

Moderate condition (1.3)

Cirrhosis of the liver. Ascites, impaired consciousness and / or hemodynamics. In need of care.

The condition is severe (1,2,3,4).

Wegener's granulomatosis. Fever, lung infiltrates, shortness of breath, weakness, progressive decline in kidney function. Arterial hypertension is medically controlled. Prefers to be in bed but can walk and take care of himself.

Condition of moderate severity (1,2,3,4).

Wegener's granulomatosis. Deviations in blood tests persist, CRF IIst.

Satisfactory condition.

APPENDIX 4

Determination of medical age, significance for diagnosis .

1) Determination of medical age is of no small importance, for example, to forensic practice. A doctor may be asked to determine the age due to the loss of documents. This takes into account that the skin loses elasticity with age, becomes dry, rough, wrinkled, pigmentation, keratinization appears. At the age of about 20 years, frontal and nasolabial wrinkles already appear, about 25 years old - at the outer corner of the eyelids, by 30 years old - under the eyes, at 35 years old - on the neck, about 55 - in the area of ​​the cheeks, chin, around the lips.

On the hands of up to 55 years, the skin, taken in a fold, quickly and well straightens out, at 60 years old it straightens out slowly, and at 65 it no longer straightens out on its own. Teeth with age are erased on the cutting surface, darken, fall out.

By the age of 60, the cornea of ​​the eyes begins to lose transparency, whitishness / arcussenilis / appears along the edges, and by the age of 70 the senile arc is already clearly expressed.

It should be remembered that medical age does not always correspond to metric. There are eternally young subjects, on the other hand - prematurely aged. Patients with increased thyroid function look younger than their years - usually thin, slender, with delicate pink skin, sparkle in the eyes, mobile, emotional. Premature aging is caused by mexedema, malignant tumors and some long-term severe diseases.

Determination of age is also important because certain diseases are characteristic of each age. There is a group of childhood diseases that are studied in the course of pediatrics; on the other hand, gerontology is the science of diseases of the elderly and senile age /75 years and more/.

Age groups /Guide to gerontology, 1978/:

Children's age - up to 11 - 12 years.

Teenage - from 12 - 13 years to 15 - 16 years.

Youth - 16 - 17 years old to 20 - 21 years old.

Young - from 21 - 22 years old to 29 years old.

Mature - from 33 years to 44 years.

Medium - from 45 years to 59 years.

Elderly - from 60 years to 74 years.

Old - from 75 years to 89 years.

Long-livers - from 90 and more.

At a young age, they often suffer from rheumatism, acute nephritis, and pulmonary tuberculosis. In adulthood, the body is most stable, least prone to disease.

The patient's age must also be taken into account due to the fact that it has a significant impact on the course of the disease and the prognosis /outcomes/: at a young age, the disease mostly proceeds rapidly, their prognosis is good; in senile - the reaction of the body is sluggish, and those diseases that end in recovery at a young age, for example, pneumonia, in old people are often the cause of death.

Finally, in certain age periods, there are sharp shifts in both the somatic and neuropsychic spheres:

a) puberty /pubertal period/ - from 14 - 15 years to 18 - 20 years - characterized by increased morbidity, but relatively low mortality;

b) the period of sexual withering / menopause / - from 40 - 45 years to 50 years is marked by a tendency to cardiovascular, metabolic and mental diseases / there are functional disorders of the vasomotor, endocrine-nervous and mental nature /.

c) The period of aging - from 65 years to 70 years - during this period it is difficult to separate the purely age-related phenomena of wear and tear from the symptoms of a particular disease, in particular atherosclerosis.

The doctor determines the correspondence of gender and age to passport data already when questioning the patient, records deviations in the medical history if they are detected, for example: “the patient looks older than his years” or “medical age corresponds to the metric age”.

METASTABLE STATE- a state of incomplete macroscopic equilibrium. system corresponding to one of the minima thermodynamic. potential of the system for given ext. conditions. A stable (stable) state corresponds to the deepest minimum. Homogeneous system in M. with. satisfies the stability conditions thermodynamic equilibrium relatively small perturbations physical. parameters (entropy, etc.). For sufficiently large perturbations, the system goes into an absolutely stable state.

Large class M. s. associated with phase transitions 1st kind (crystal liquid gas). For single component system Gibbs energy Ф(Т, P) [or chem. potential-number of particles in the system] is represented by a surface with self-intersection. On the line of intersection of chem. potentials of two phases, equilibrium coexistence of phases is possible. Dot s in fig. 1 - the trace of such a line on the plane M. With. two phases correspond to plots . M. s. characterized by a finite lifetime.

In the absence of a competing (more stable) phase, the decay of M. s. begins with the emergence of viable nuclei as a result of fluctuations, for example, of liquid droplets in a supersaturated vapor or vapor bubbles in superheated liquid(cm. hypothermia, overheating).

Min. Work W, which needs to be spent to create a nucleus of radius r, consists of volume and surface contributions. Addiction W from r shown in fig. 2. The position of the maximum determines the size of the critical. germ. With increasing supersaturation, the values ​​decrease. The growth of the embryo is determined by thermodynamics. For spherical embryos, where is the coefficient. at the phase boundary, - pressure in the critical nucleus and in the external. phase. Instead of the pressure difference, you can enter the amount of subcooling (overheating) | T - T0 | at a given pressure or the difference in chemical. potentials Dm of the metastable and stable phases, is the specific volume of the stable phase.

In most real situations, the decay of M. s. occurs before reaching a noticeable rate of homogeneous nucleation, the theory belongs to Krom. The beginning of the phase transition is facilitated by the influence of the walls and the presence of decomp. inclusions, which significantly reduce the work of formation of viable nuclei of the stable phase. In this case, one speaks of heterogeneous nucleation. Specially designed experiments with superheated and supercooled liquids lead to results that are in agreement with the predictions of fluctuation theory. (homogeneous) nucleation. In experiments, an alternative to a slow change of state in a "pure" system is the mode of rapid creation of such a supersaturation, with Krom basic. the fraction of the phase transition is due to the fluctuation mass. nuclei, and the contribution of heterogeneous nucleation is insignificant.

Two phases that are metastable with respect to a third phase can coexist with each other. In this case, the usual phase equilibrium conditions are satisfied:

An example is a supercooled liquid and the vapor above it T tr - temp-pa triple point crystal - liquid - vapor. Dr. an example is the equilibrium of a crystal - liquid on the continuation of a line beyond the triple point, i.e. at. A similar technique for constructing extended ones is used for systems with polymorphic transformations (see. Polymorphism).This is due to the fact that MH. crystalline materials are obtained on the basis of metastable modifications. Great practical. the construction of the graphite-diamond phase diagram was important. In two- and multi-component systems, it is necessary to take into account the possibility of metastability caused by concentration. supersaturation.

M. s. - non-equilibrium state of thermodynamic. systems. For definiteness, it is usually assumed that the system located in the M. s. has pro-relaxed in all respects, except for those fluctuations. modes, to-rye lead to the emergence of viable embryos. In other words, the characteristic waiting time for the decay of M. s. longer than other relaxation times (temperature, concentration, etc.). In this case, there is a quasi-static continuation of the thermodynamic properties of an equilibrium system into the area of ​​M. s. If the formulas are not followed. the conditions of metastability and nonequilibrium of phases are related in a more complex way. For example, a vitrified (very viscous) liquid is metastable (at ), but its structure and properties depend on the history of the system (see Fig. glassy state).

With the existence of M. s. related phenomena during phase transitions, for example. with cyclic remagnetization of ferromagnets, in cloud chambers, in bubble chambers. MH. technically important materials, including steels, aluminum alloys, are metastable systems.

Lit.: Landau L. D., Lifshits E. M., Statisticheskaya, part 1, 3rd ed., M., 1976, p 21, 83, 162; Skripov V.P., Metastable liquid, M., 1972; Sivukhi n D.V., General course physics, 2nd ed., [vol. 2], M., 1979; Frenkel Ya. I., Kinetic theory liquids, L., 1975.

AT. P. Skripov.

1

Treatment in intensive care stressful situation for the patient. Indeed, in many intensive care centers there are no separate wards for men and women. Often patients lie naked, with open wounds. Yes, and you have to cope with the need without getting out of bed. The intensive care unit is represented by a highly specialized unit of the hospital. Patients are referred to the intensive care unit:

In critical condition; with serious illnesses; in the presence of severe injuries; after anesthesia; after a complex operation.

Intensive care unit, its features

Due to the severity of the condition of patients in the intensive care unit, round-the-clock monitoring is carried out. Specialists monitor the functioning of all vital organs and systems. The following indicators are monitored:

Level blood pressure; blood oxygen saturation; breathing rate; heart rate.

To determine all these indicators, a lot of special equipment is connected to the patient. For...

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2

Resuscitation - a set of measures aimed at restoring the functions of the body that have been disturbed or lost due to any factors.

Functions, the violation of which leads to the placement of the patient in intensive care (there may be one item or all at once):

Failures in cardiac activity; problems with independent breathing; impaired brain activity; failure in the metabolic system of the body; some others.

Important: if a person is in intensive care, his condition is already very serious, in this department, doctors are fighting to save the patient's life. However, it happens that the period of remission is replaced by an exacerbation, then a person from an ordinary ward ends up in intensive care.

Diagnostics: classification of conditions

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3

The severity of the general condition of the patient is determined depending on the presence and severity of decompensation of vital body functions. Treatment of critically ill patients general condition carried out in the intensive care unit.

Treatment in intensive care is a very stressful situation for the patient. Indeed, in many intensive care centers there are no separate wards for men and women. Often patients lie naked, with open wounds. Yes, and you have to cope with the need without getting out of bed. The intensive care unit is represented by a highly specialized unit of the hospital.

To determine all these indicators, a lot of special equipment is connected to the patient. Patients who are in the intensive care unit after the operation have temporary drainage tubes. The extremely serious condition of patients means the need to attach to the patient a large amount of special equipment necessary to monitor vital ...

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4

Girls, on one site today there were heated discussions about "What I will never do with the next repair." The topic turned out to be so relevant and interesting that I decided to bring it up here. Let's share our mistakes and successes in repairing and furnishing our nests. I'll start with myself.

Perhaps such posts have already been written, but I overlooked it, but I will write again, armed means warned. Yesterday I was at home in Moscow, I missed my granddaughter and my daughter, the granddaughter got sick, everything was as always, the granddaughter is recovering, the daughter was doing household chores, and we played, laughed with the granddaughter, everything was great. Nothing foreshadowed a storm and a spoiled mood until such an SMS came

Many of the photographs are touching to the core. Below are those that touched the strings of my soul. You can attach those photos that have affected you in some way.

My grandmother is 90 years old, she has 5 children. My grandfather has been gone for over 40 years. He cheated, there were even children in the next street. What am I for? To that...

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5

APPENDIX 3

METHODOLOGICAL DEVELOPMENT FOR TEACHERS AND STUDENTS

TO THE TOPIC "GENERAL EXAMINATION OF THE PATIENT"

Criteria for assessing the general condition

1. Decompensation of the functions of vital organs and systems (respiratory, CCC).

2. Indications for emergency hospitalization, as well as the urgency and scope of therapeutic measures.

3. Nearest forecast.

4. Motor activity and the need for care.

The severity of the condition is determined by a complete examination of the patient.

1. during questioning and general examination (complaints, consciousness, position, skin color, swelling ...);

2. when examining systems (respiratory rate, heart rate, blood pressure, ascites, bronchial breathing or the absence of breath sounds over the lung area ...);

3. after additional methods (blasts in the blood test and thrombocytopenia, heart attack on the ECG, bleeding stomach ulcer on FGDS ...).

There are: a satisfactory condition, a moderate condition, a serious condition and an extremely serious condition ....

0 0

6

Resuscitation - psychological and physical discomfort for the patient?

Treatment in intensive care

Misunderstanding by patients of the peculiarities of the treatment regimen of the intensive care unit often causes serious complications, sometimes representing a great danger to their lives. In addition, treatment in intensive care is a great psychological stress for patients. Reducing the level of anxiety and anxiety, as well as preventing the development of severe complications associated with violation of the resuscitation treatment regimen by patients are the main goals of this educational article. This article will be especially useful for patients preparing for major operations, after which further treatment is expected in the intensive care unit.

The intensive care unit is a highly specialized unit of the hospital. The main contingent of intensive care patients are critically ill patients with serious illnesses and injuries, as well as severe...

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Father (86 years old) is in intensive care with a stroke

Hello, Doctor.

Father (86 years old) is in intensive care with a stroke. It began with the fact that on Sunday evening he became ill, an hour later I returned home and measured the pressure. the top was 200+ and a strong arrhythmia. after which the ambulance was called. The doctors gave injections. but the pressure remained high, the cardiogram could not be taken, and it was decided to take him to the hospital. A cardiogram was taken there and placed in cardiology (upper pressure at that time was 220).

By the way, with a little help, my father got into the car himself, but he could no longer get out, his speech became slurred, his movements were like those of a very drunk person.

A drip was placed in the department. then they made an injection. After some time, he felt better, his speech and coordination of movements were completely restored, he even walked around the ward a little.

The morning began with the fact that at 04.00 he moved out of bed onto the floor, it was difficult to lift him back, his arms and legs were ...

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Currently, the prevalence of stroke is 3-4 cases per 1000 people in Russia, with the majority being patients with ischemic stroke - about 80% of cases, the remaining 20% ​​are patients with a hemorrhagic type of disease. For relatives and friends of the victim, an attack of acute cerebrovascular accident is often a surprise, and important issue What worries them is the question of how many are in intensive care after a stroke and how long the treatment in the hospital lasts in general.

Stroke treatment consists of several stages.

All treatment of acute cerebrovascular accident consists of several stages:

Prehospital stage. Treatment in the intensive care unit and intensive care unit. Treatment in the general ward.

The issue of the number of days of hospital stay for stroke is regulated by the treatment standards developed by the Ministry of Health. The length of stay of patients in hospital conditions is 21 ...

0 0

9

Terra_Nova, stop tormenting yourself.. If there was something bad, you would have already been invited to a conversation.
While they say that the state is stable - relax the rolls and calm down. Soon she will be transferred to the ward, apparently a chair is waiting.
If you're really worried, send dad, let him go looking for a surgeon.
Just such thoughts as you have, and such torment - why? If there is really just a recovery after the operation, maybe not as fast as in the young.

I don't know, no one has ever turned me down. Yes, I waited for doctors under the operating room, anesthesiologists, I waited for several hours. But I always received information. Ignorance is worse.

Again, resuscitators come out to talk about the condition of the patients. Put 500 rubles in your pocket, everyone will tell you how ...

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10

View full version: The condition is serious. What does it mean?

The husband was taken to the hospital by ambulance. The operation was performed at night, and he is now in intensive care. It makes no sense for me and the children from the suburbs to go in such weather, they said they would not let me in. In the help desk they say "he is in intensive care, his condition is serious, the pace is 36.7" and they hang up.
Please explain what "a serious condition" means?, ... and I can’t find out how he recovered from anesthesia ... For the first time I encounter this in such a way that it concerns me personally .....

24.12.2009, 14:25

well, after the operation, the condition is always serious,
You can’t just call it light .... or moderate)
and the fact that the temperature is normal is already GOOD!
don't worry, everything will be fine.
Peace to you, and a speedy recovery to your husband: 091:

24.12.2009, 15:42

In intensive care, there are always 2 statuses of the condition: extremely severe and severe. When it is stable, they will transfer to the department.

Husband soon...

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11

Svetlana asks:

January 27, 23:43, 2011

Hello. My grandmother is 86 years old, she is in the hospital for a planned examination, she always lies down in the winter. Yesterday she left the ward, and when she came back and went to her bed, she fell ill and hit her face on the bedside table. The doctors came running and said that she had an ischemic stroke. Eyes open but unresponsive. Damaged the right side. From the hospital where she lay she was transferred to neurosurgery, and then she became ill and began to vomit black. The doctors transferred her to the intensive care unit now she is in a coma. He is said to be in stable condition. My question is what are we preparing for? How long can a coma last? Will speech be restored with a favorable outcome, etc.

January 28 12:14, 2011

Unfortunately, in this situation, the prognosis is extremely unfavorable. Probably, the area of ​​brain damage is very large, so the risk of death is high. But even if your grandmother comes out of a coma, most likely she will have ...

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12

The severity of the general condition of the patient is determined depending on the presence and severity of decompensation of vital body functions. In accordance with this, the doctor decides on the urgency of the conduct and the necessary volume of diagnostic and therapeutic measures, determines the indications for hospitalization, transportability and the likely outcome (prognosis) of the disease.

In clinical practice, there are several gradations of the general condition:

Satisfactory moderate severe extremely severe (pre-agonal) terminal (atonal) state of clinical death.

The doctor gets the first idea about the general condition of the patient, getting acquainted with the complaints and data of the general and local examination: appearance, state of consciousness, position, fatness, body temperature, color of the skin and mucous membranes, the presence of edema, etc. The final judgment on the severity of the patient's condition is made on the basis of the results of the study of internal organs. The definition is of particular importance...

0 0

13

This has always been a stumbling block - determining the severity of the patient. The therapist sees that "Aunt Glasha" is difficult, the resuscitator - which is fully compensated. Even among colleagues there are often conflicting opinions. I've been thinking for a long time, maybe I "invented the wheel" in a new way, starting from such a stratification: (can be corrected)

Gradation of the severity of the general condition
Satisfactory condition: no violations of the vital functions of the body,
Moderate severity: no violations of the vital functions of the body, in the presence of symptoms characteristic of this disease,
Severe condition: moderate violations of vital functions in 1-2 indicators,
Extremely serious condition: gross violations of vital functions simultaneously in several parameters,
Terminal state: critical violations of vital functions.

central nervous system
Satisfactory condition: 15 GSC points: clear consciousness, active wakefulness, complete correct ...

0 0

(from meta ... and lat. stabilis - stable) in thermodynamics, the state of unstable equilibrium of a physical macroscopic system, in which the system can be for a long time. Examples. . superheated or supercooled liquid and supercooled (supersaturated) vapor can serve (see Superheating and Supercooling). A liquid, such as water, which has been thoroughly cleaned of foreign solid particles and gas bubbles (vaporization centers), can be heated to a temperature higher than the boiling point at a given pressure. If centers of vaporization appear in the superheated liquid (or they are introduced artificially), then the liquid will explosively turn into vapor - a state that is stable at a given temperature. In turn, steam in which there are no condensation centers (solid particles, ions) can be cooled to temperatures at which it is stable liquid state, and get supercooled (supersaturated) steam. In nature, supersaturated water vapor is formed, for example, during the rise of air masses heated near the earth's surface and their subsequent cooling caused by adiabatic expansion. M.'s emergence with. explained by the theory of thermodynamic equilibrium (see Thermodynamic equilibrium). A state of equilibrium closed system corresponds to the maximum entropy S. At constant volume V and temperature T equilibrium corresponds to a minimum free energy F (Helmholtz energy), and at constant pressure p and temperature T - minimum thermodynamic potential G (gibbs energy). However, certain values ​​of external parameters (p, V, T, etc.) may correspond to several extrema (maxima or minima) of one of the functions listed above (Fig.). Each of the relative minima of the function F or G corresponds to a state that is stable with respect to small impacts or fluctuations. Such states are called metastable. With a slight deviation from M. s. the system returns to the same state, however, with respect to large deviations from equilibrium, it is unstable and goes into a state with absolute minimum thermodynamic potential, which is stable with respect to finite deviations of the values ​​of physical parameters from equilibrium. Thus, although M. s. within certain limits, it is stable, sooner or later the system nevertheless passes into an absolutely stable, stable state. Possibility of M.'s implementation with. associated with the features of the transition of the system from one stable state to another (with the kinetics of phase transitions). The phase transition begins with the appearance of nuclei of a new phase: vapor bubbles in the case of a liquid-to-vapour transition, microcrystals in the case of a liquid transition to a crystalline state, etc. For the formation of nuclei, work is required to create interfaces between two phases. The growth of the nuclei formed is hindered by the significant curvature of their surface (see Capillary phenomena), which leads during crystallization to increased solubility of the nuclei of the solid phase, during liquid condensation - to the evaporation of tiny droplets, and during vaporization - to increased vapor elasticity inside small bubbles. These factors can make emergence and growth energetically unfavorable. M., Statistical physics, M., 1964; Shtrauf E.A., Molecular physics, M. - L., 1949; Samoilovich A . G., Thermodynamics and statistical physics, 2nd ed., M., 1955; Skripov. P., Metastable liquid, Moscow, 1972. . . Myakishev.

Metastable state(from Greek μετα "through" and lat. stabilis"stable"), a state of unstable equilibrium physical system, in which the system can be for a long time. What is a metastable state can be understood from the picture on the right: state 1: metastable- state, the stability of which is preserved under small perturbations; state 2: unstable- state, the stability of which is violated under infinitely small perturbations; state 3: stable- a state, the stability of which is preserved under large disturbances. Metastable states are widely found in nature and are used in science and technology. The existence of metastable states is associated, for example, with the phenomena of magnetic, electrical, and elastic hysteresis, the formation of supersaturated solutions, steel hardening, glass production, etc. Metastable states correspond to one of the minima of the thermodynamic potential of the system at given external conditions. A stable (stable) state corresponds to the deepest minimum. A homogeneous system in a metastable state satisfies the conditions for the stability of thermodynamic equilibrium C P >C V > 0, (dP / dV)T < 0, относительно малых возмущений физических параметров (энтропии, плотности и др.). При достаточно больших возмущениях система переходит в абсолютно устойчивое состояние. Большой класс метастабильных состояний связан с phase transitions 1st kind (crystal liquid gas). Critical state - a state of matter that occurs when the difference between phases that are in equilibrium with each other (for example, between a liquid and its vapor) disappears.

10.Internal energy of a real gas.

11. Joule-Thomson effect. Liquefaction of gases and obtaining low
temperatures. The Joule-Thomson effect is a change in gas temperature during adiabatic throttling - a slow flow of gas under the action of a constant pressure drop through a throttle (porous partition). This effect is one of the methods for obtaining low temperatures. Liquefaction of gases includes several stages necessary to transfer the gas to a liquid state. These processes are used for scientific, industrial and commercial purposes. Many gases can be reduced to a liquid state by simple cooling under normal atmospheric pressure, others, such as carbon dioxide, also require an increase in pressure. Liquefaction is used to study the fundamental properties of gas molecules (for example, intermolecular forces of interaction), to store gases. Gases are liquefied in special condensers that absorb the heat of vaporization and are converted into gaseous state in evaporators where the heat of vaporization is released. All substances, including those that are in the "normal terrestrial conditions" in a gaseous state, can be in three main states - liquid, solid and gaseous. each of the substances behaves according to its phase diagram, general form which is similar for all substances. According to this diagram, in order to liquefy a gas, either a decrease in temperature or an increase in pressure, or a change in both of these parameters is necessary. Liquefaction of gases is a complex process that includes many compressions and expansions of a gas to achieve high pressure and low temperatures, using, for example, expanders .Liquid oxygen is used in hospitals to be converted to a gaseous state and then used by patients with breathing problems. Liquid nitrogen is used in medicine in cryosurgery,

16The phenomenon of transfer is diffusion.The mass transfer process is called diffusion. Let us now consider two regions with different concentrations of the same substance or different substances. Spontaneous flows of molecules arise, leveling the concentration. Experimentally installed Fick's law: , where is the density (the law can be written in terms of concentration),
- diffusion coefficient, , the “-” sign indicates that diffusion goes from an area with a higher concentration towards an area with a lower concentration.

17. The phenomenon of transfer - thermal conductivityThe process of energy transfer is called heat conduction..It is observed if in one area of ​​the environment kinetic energy there are more molecules than in the other, i.e. . When molecules collide, their velocities of movement are aligned (heat is transferred). The amount of heat must be transferred from a heated body to a cold one.
- in proportion to the area through which the transfer occurs, time and temperature difference per unit length (temperature gradient): - experimentally established Fourier law. The sign “-“ indicates the direction of transfer, that heat is transferred from a more heated body to a less heated one, - the coefficient of thermal conductivity,