Temperature curves. Types, types of fevers and the course of febrile syndrome Types of fevers according to the degree of temperature increase

Fever is assessed by duration, degree of increase in body temperature and the nature of the change in the temperature curve.

By duration Fever can be ephemeral (from several hours to two days), acute (up to 15 days), subacute (up to 45 days) and chronic (over 45 days).

According to the degree of temperature increase bodies distinguish between subfebrile (not higher than 38 C), moderate (from 38 to 39 C), high (from 39 to 40 C), excessively high (from 40 to 41 C) and hyperpyretic (above 41 C) fever.

In its turn low-grade fever can be low (up to 37.5 C) and high (above 37.5 C). Taking into account the pathogenesis of increased body temperature, low-grade fever in most cases is also regarded as fever.

Types of fever curve

By the nature of the temperature curve change The following types of fever are distinguished:

constant(f. continua) - temperature exceeds 39 C with daily variations of less than one degree; occurs with typhoid infection, lobar pneumonia, erysipelas;
relapsing-remitting(f. remittens) - daily fluctuations in body temperature exceed 1 C, it can drop below 38 C, but does not reach normal numbers; a similar type of fever is observed in bronchopneumonia, viral diseases, rheumatism, tuberculosis, etc.;
intermittent or intermittent(f. intermittens), - normal (apyrexia period) or subnormal body temperature (1-2 days) alternates with increased body temperature with daily fluctuations of several degrees; inherent in malaria, pyelonephritis, pleurisy, sepsis;
debilitating or hectic(f. hectica), - the temperature curve resembles that of remitting fever, but its daily fluctuations are 4-5 C; may occur in severe forms of tuberculosis and sepsis. An increase in body temperature is associated with abundant absorption of pyrogenic substances;
returnable(f. recurrens) - high fever, alternating with periods of normal body temperature, lasting several days. The febrile period begins suddenly and ends just as suddenly. This type of reaction is observed in relapsing fever and depends on the entry of spirochetes into the blood;
wavy(f. undulans) - a gradual increase in temperature from day to day to high numbers, followed by a decrease in it and the repeated formation of individual waves; occurs in lymphogranulomatosis and brucellosis;
perverted(f. inversa) - higher body temperature in the morning than in the evening, occurs in patients with tuberculosis, sepsis, with tumor processes, etc.;
wrong(f. irregularis) - a moderate or high increase in body temperature without any patterns with various and incomplete daily fluctuations; may occur with meningitis, influenza, etc.

The severity and nature of the temperature reaction depend on the nature of the pathological process, its severity and form, as well as on the reactivity of the body. The age of the patient, his constitutional characteristics, the state of the endocrine, immune, central nervous systems and other factors are of certain importance.

Due to the early use of antibiotics, antipyretics or etiotropic therapy, the types of fever curves are now of relative importance. Their shape can vary significantly and is rarely typical. This makes it difficult to use the temperature curve for diagnostic purposes.

More often, febrile syndrome is only an indicator of “trouble” in the body. And yet, in infectious diseases, clinical variants or types of fever curve are one of the reference symptoms for differential diagnosis.

On the page "Etiology of fever" it was already said that there are two types of fever: infectious and non-infectious.

By degree temperature rise fevers are divided into:

subfebrile - up to 38°C;
moderate febrile - over 38°C and up to 39°C;
high febrile - over 39°C and up to 41°C;
hyperpyretic - over 41°C.

By type of temperature curve fevers are divided into:

By time febrile process:

chronic fever - more than 45 days;
subacute fever - up to 15-45 days;
acute fever - up to 15 days;
ephemeral fever - several hours or days.

General classification of fevers:

psychogenic fever is associated with emotional experiences;
drug fever is caused by taking medications;
neurogenic fever is associated with diseases of the central nervous system;
post-traumatic fever is observed after various injuries or surgical interventions;
false fever - simulation of an increase in temperature, usually by children;
fever of unknown origin - the cause of the increase in temperature cannot be determined.

By mechanism of action fevers are divided into:

pink fever- the body maintains a balance between heat production and heat transfer (the patient’s skin is warm, moist, slightly pink, the general condition is satisfactory);
white fever- the heat production of the patient’s body does not correspond to the possibility of its heat transfer due to spasm of the skin vessels and a sharp decrease in heat transfer (the patient’s skin is cold, pale with a bluish or marbled tint). Here we can draw an analogy with a car whose thermostat has not opened, as a result of which the engine begins to “boil”, since the coolant does not have access to the radiator through which it is cooled. There are a great many reasons for the occurrence of spasms, but in any case white fever is a good reason to immediately call an ambulance or a local therapist at home.

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The hyperthermic reaction in patients occurs in 3 periods:

1st period - rise in body temperature (chill period) - heat production prevails over heat transfer. Heat transfer is reduced due to the narrowing of skin blood vessels.

Problems: weakness, malaise, headache, muscle pain, “ache” throughout the body (symptoms of general intoxication). An increase in body temperature and spasm of peripheral vessels causes chills and trembling in the patient, he cannot warm up. The patient is pale, the skin is cold to the touch.

Nursing interventions:

1) put to bed, create peace;

2) warm the patient with heating pads, a warm blanket, hot drinks (tea or milk with honey, herbal teas);

3) monitor the external condition of the patient, conduct thermometry, monitor physiological indicators - pulse, blood pressure, respiratory rate.

2nd period - relative constancy of high body temperature (fever period, stabilization of the febrile state). Duration from several hours to several days. Skin vessels are dilated, heat transfer increases and balances the increased heat production. Stopping further increase in body temperature, stabilizing it.

Problems: fever, headache, weakness, loss of appetite, dry mouth, thirst. Objectively: facial hyperemia, skin hot to the touch, cracks on the lips. At high temperatures, disturbances of consciousness, hallucinations, and delirium are possible.

Nursing interventions:

1) monitor the patient’s adherence to strict bed rest (individual nursing station);

2) to enhance heat transfer, cover the patient with a light sheet, wipe the skin with a solution of vinegar or alcohol, provide an ice pack, and apply a cold compress;

3) soften lips with a cosmetic product;

4) provide at least 1.5-2 liters of fortified drinks (tea with lemon, juices, fruit drinks, mineral waters, rosehip infusion);

5) feed liquid, semi-liquid and easily digestible food in small portions 5-6 times a day (dietary table No. 13);

6) monitoring body temperature, pulse, blood pressure, respiratory rate;

7) control of physiological functions (especially diuresis - the amount of urine excreted);

8) assessment of behavioral response.

3rd period - decrease in body temperature (period of weakness, sweating). Heat production is reduced compared to heat transfer. The period proceeds in different ways: favorable and unfavorable.

Favorable option- gradual decrease in body temperature over several days. This drop in temperature reaction is called lytic - lysis.

83. Hyperthermia.

52. The concept of fever. Types and periods of fever.

Hypothermia.

Hyperthermia.

This is a violation of the body's thermal balance, characterized by an increase in body temperature above normal values.

Hyperthermia can be exogenous and endogenous. Exogenous - occurs at high ambient temperatures, especially if heat transfer is simultaneously limited and heat production increases during physical work (intense). Endogenous - occurs due to excessive psycho-emotional stress, the action of certain chemical agents that enhance the oxidation process in mitochondria and weaken the accumulation of energy in the form of ATP.

Three stations:

I. Compensation stage - despite the increase in ambient temperature, body temperature remains normal, the thermoregulation system is activated, heat transfer increases and heat production is limited.

2. Stage of relative compensation - heat production prevails over heat transfer and, as a result, body temperature begins to rise. A combination of thermoregulation disorders is characteristic: a decrease in heat radiation, an increase in oxidative processes, general agitation while maintaining some protective and adaptive reactions: increased sweating, hyperventilation of the lungs.

3. Decompensation stage - inhibition of the thermoregulation center, sharp inhibition of all heat transfer pathways, increased heat production as a result of a temporary increase in oxidative processes in tissues under the influence of high temperature. At this stage, external respiration occurs, its character changes, it becomes frequent, superficial, blood circulation is disrupted, arterial hypotension, tachycardia, and then rhythm inhibition. In severe cases, hypoxia appears and convulsions occur.

What is the difference between fever and hyperthermia? It would seem that in both cases there is an increase in body temperature, however, fever and hyperthermia are fundamentally different conditions.

Fever is an active reaction of the body, its thermoregulation system to pyrogens.

Hyperthermia is a passive process - overheating due to damage to the thermoregulatory system. Fever develops regardless of the ambient temperature, and the degree of hyperthermia is determined by the external temperature. The essence of fever is the active restructuring of the thermoregulatory system; temperature regulation is maintained. With hyperthermia, due to disruption of the thermoregulatory system, the regulation of body temperature is disrupted.

Hypothermia.

This is a violation of heat balance, accompanied by a decrease in body temperature below normal conditions. Can be exogenous and endogenous. There are three stages of development:

1. Compensation stage.

2. Stage of relative compensation.

3. Stage of decompensation.

The property of hypothermia is to reduce the body's need for oxygen and increase its resistance to pathogenic influences. Used in practical medicine. During severe surgical operations, general or local (craniocerebral) hypothermia is used. The method is called “artificial hibernation.” Along with general and local cooling of the brain, such operations use medications that weaken protective and adaptive reactions aimed at maintaining body temperature at a normal level. These drugs reduce the body's need for oxygen. Mild hypothermia is used as a method of hardening the body.

Date of publication: 2015-02-03; Read: 35958 | Page copyright infringement

STAGES AND TYPES OF FEVER

Lecture 8

Topic: Violation of thermoregulation

Plan

1.Hyperthermia.

2. Hypothermia.

3. Fever, its causes, stages, types.

4. The meaning of fever.

Thermoregulation carries out a balance between heat generation and heat release. There are two main types of thermoregulation: chemical (its main mechanism is increased heat generation during muscle contractions - muscle tremors) and physical (increased heat transfer due to the evaporation of fluid from the surface of the body during sweating). In addition, the intensity of metabolism and the narrowing or dilation of skin vessels have a certain significance for heat production and heat transfer.

The functioning of the thermoregulation system can be disrupted under the influence of various pathogenic influences, as a result of which the body temperature deviates from the norm, and this can lead to disruptions in vital functions. Thermoregulation disorders are manifested by overheating (hyperthermia) and hypothermia (hypothermia).

HYPERTHERMIA

Hyperthermia- disturbance of the body’s thermal balance, characterized by an increase in body temperature above normal values. Distinguish exogenous and endogenous hyperthermia. Exogenous hyperthermia occurs at high environmental temperatures (hot workshops in production), especially if heat transfer is simultaneously limited (warm clothing, high humidity and low air mobility). The development of hyperthermia is also facilitated by increased heat production, for example, during intense physical work. Some forms of exogenous hyperthermia can be acute and extremely life-threatening. They received a special name - heatstroke And sunstroke. Endogenous hyperthermia can occur with excessive prolonged psycho-emotional stress and endocrine diseases.

In typical cases, hyperthermia develops in three stages. The first is compensation stage, in which, despite the increase in ambient temperature, the body temperature remains at a normal level (36.5-36.7 ° C). This is due to the activation of the thermoregulation system, as a result of which heat transfer significantly increases and heat production is limited.

Subsequently, if the ambient temperature is excessively high or the thermoregulation system is disrupted, relative compensation stage. During this period, there is a predominance of heat production over heat transfer, as a result of which body temperature begins to rise. Characteristic of this stage is a combination of thermoregulation disorders (decreased heat radiation, increased oxidative processes, general excitation) while maintaining some protective-adaptive reactions (increased sweating, hyperventilation).

The third stage of hyperthermia - decompensation. At this time, due to inhibition of the thermoregulation center, sharp limitation of all heat transfer paths and an increase in heat production as a result of a temporary increase in oxidative processes in tissues under the influence of high temperature. During the decompensation stage, the body temperature becomes the same as the ambient temperature. External respiration is depressed, its character changes, it becomes frequent, superficial or even periodic. Blood circulation is also disrupted - arterial hypotension and tachycardia develop, which turns into depression of the heart rhythm.

Topic 11. Types, types and periods of fever educational objectives

In severe cases, due to damage to these systems, hypoxia appears and convulsions occur. Patients lose consciousness, which is typical for hyperthermic coma.

Heatstroke- acute exogenous hyperthermia. This state is essentially the third stage of hyperthermia, the stage of decompensation. Heat stroke usually occurs when the ambient temperature is high, when heat transfer is sharply limited,(for example, on a march among military personnel in the southern regions, among workers in hot shops). In this case, the first and second stages of hyperthermia do not appear, which is associated with a rapid disruption of thermoregulation. Body temperature rises to ambient temperature. External respiration is impaired, heart function weakens and blood pressure drops. Consciousness is lost.

Sunstroke is a peculiar acute form of local hyperthermia and occurs as a result direct action of the sun's rays on the head. Overheating of the brain and thermoregulation centers leads to disruption of the entire system of maintaining body temperature, which, as a result, increases a second time. The symptoms of sunstroke are similar to those of heatstroke. In case of heat and sunstroke, immediate pre-medical and medical assistance is required.

HYPOTHERMIA

Hypothermia- disturbance of thermal balance, accompanied by a decrease in body temperature below normal values.

Highlight exogenous and endogenous hypothermia. Exogenous hypothermia occurs when the ambient temperature decreases (during the cold season, during operations using ice, cold water, chilled air). The aggravating factor is increased heat transfer, what is promoted, for example, drinking alcohol, inappropriate clothing etc. The development of hypothermia is also facilitated by reduced heat production (low physical activity).Endogenous hypothermia occurs with prolonged immobilization, endocrine diseases (hypothyroidism, insufficiency of the adrenal cortex).

Hypothermia also has three stages of development. The first is compensation stage when, despite the low ambient temperature, the body temperature remains at a normal level. This is achieved, first of all, limitation of heat transfer- heat radiation, evaporation and convection with a decrease in air movement at the surface of the body.

Of significant importance in limiting heat transfer is the activation of the sympathetic-adrenal system, which causes spasm of the micro-vessels of the skin, thereby limiting the pathways for heat transfer. Along with this, as a rule, there is an increase in heat production due to increased motor activity, contraction of smooth muscles of the skin (“goose bumps”) and increased oxidative processes in tissues. Subsequently, at low ambient temperatures, or weakness of the thermoregulation system, the stage begins relative compensation, which is characterized by a combination thermoregulation disorders(dilation of skin microvessels and increased heat transfer) and some protective and adaptive reactions (increased oxidative processes in tissues). During this transitional stage, heat transfer prevails over heat production, as a result of which body temperature begins to decrease. With increasing severity of thermoregulation disorders, the third stage of hypothermia develops - stage of decompensation. It is characterized by the development of hypoxia, which increases in severity due to weakening of external respiration, depression of cardiac activity, and microcirculation disorders. All this leads to a weakening of oxidative processes in tissues. Mild hypothermia is used in the same way as a method of hardening the body.

Fever - a protective-adaptive reaction of the body that occurs in response to the action of pyrogenic stimuli and is expressed in the restructuring of thermoregulation to maintain a higher than normal body temperature. It is manifested by a temporary increase in body temperature, regardless of the ambient temperature, and is accompanied by changes in metabolism, physiological functions and protective and adaptive capabilities of the body. Fever occurs in many diseases, but it always occurs in a stereotypical manner, therefore it is classified as a typical pathological process.

CAUSES OF FEVER

STAGES AND TYPES OF FEVER

Fever occurs in stages. Identify the stage rise temperature, stage of it relative standing And temperature drop stage. During the rising stage, the temperature can increase quickly (over several tens of minutes) or slowly (over days, weeks). The duration of the temperature can also be different and amount to several hours or even years. According to the degree of maximum temperature rise during stage of standing fever is divided into mild (low-grade) - up to 38 °C, moderate (febrile)- 38.0-39.0 °C, high (low-grade fever) -39.0-41.0°C and very high (hyperpyretic)- above 41.0 °C. In the falling temperature stage may decline quickly (crisis) or slowly (lysis). With fever, the minimum body temperature is usually observed in the morning (at about 6 o'clock) and the maximum in the evening (at about 18 o'clock).

According to the degree of daily fluctuation and some other features of temperature during fever, various types are distinguished temperature curves. The type of temperature curve depends on the nature of the factor that caused the fever, and therefore the type of curve is of significant importance in the diagnosis of diseases, especially infectious ones. In addition, the type of temperature curve is determined by the properties of the body and its reactivity. In particular, a person’s age plays a significant role in the development of fever.

Highlight persistent fever, at which daily temperature fluctuations do not exceed 1.0 °C. Such fever is observed, for example, with lobar pneumonia, typhoid fever and a number of other diseases. Exists laxative, or remitting, fever. In this case, temperature fluctuations are 1.0-2.0 °C. It occurs with pneumonia, tuberculosis and other infections. Highlight intermittent fever, in which there are large temperature ranges and the morning temperature drops to normal or even below it, for example, with malaria, tuberculosis, etc. With severe infectious diseases accompanied by the development of sepsis, g e c tical fever. Body temperature in this case reaches 41.0 °C, and its fluctuations are 3.0-5.0 °C. In addition to these types of temperature curves, it is sometimes observed perverted and relapsing fever. The first is characterized by a morning rise and evening drop in temperature, for example with tuberculosis and some types of sepsis. For the second, periods of rising temperature are typical, lasting several days with short intervals of normal body temperature. This phenomenon can occur with relapsing fever. There are some other types of temperature curves (Fig. 1).

During the development of fever, a significant change occurs in the body's heat balance, i.e., the ratio of heat transfer and heat production.

The severity of the febrile process is determined by the height of the rise in body temperature. According to the level of increase in body temperature in stage II, they are distinguished:

Low-grade fever - temperature rise to 38°C;

Moderate (febrile) - from 38°C to 39°C;

High (pyretic) - from 39°C to 41°C;

Excessive (hyperpyretic) - temperature above 41 ° C.

Hyperpyretic fever can pose a threat to the patient's life, especially if the febrile process is accompanied by intoxication and dysfunction of vital organs.

The level of rise in body temperature during a febrile state is determined by a combination of factors: the type of pyrogens, the intensity of the processes of their formation and entry into the bloodstream, the functional state of thermoregulatory structures, their sensitivity to temperature and the action of pyrogens, the sensitivity of effector organs and thermoregulation systems to nervous influences coming from thermoregulation centers . In children, high and rapidly developing fever is most common. In elderly and exhausted people, body temperature rises gradually, to low values, or does not rise at all. In febrile diseases, fluctuations in high temperature obey the daily rhythm of fluctuations in body temperature: the maximum rise in temperature is at 5-7 o'clock in the evening, the minimum is at 4-6 o'clock in the morning. In some cases, the body temperature of a febrile patient, having reached a certain level, remains within these limits for a long time and fluctuates slightly during the day; in other cases this fluctuation exceeds one degree, in others the fluctuation between evening and morning temperatures is significantly more than one degree. Based on the nature of temperature fluctuations in the second stage, the following main types of fever or types of temperature curves are distinguished (Fig. 10):

1. A constant type of fever (febris continua) is observed in many infectious diseases, such as lobar pneumonia, typhoid and typhus. The constant type of fever is characterized by a prolonged increase in body temperature, which remains fairly stable and the fluctuation between morning and evening measurements does not exceed one degree. This type of fever depends on the massive intake of pyrogenic substances into the blood, which circulate in the blood throughout the entire period of elevated temperature.

2. A laxative or remitting type of fever (febris remittens) is observed with catarrhal inflammation of the lungs and bronchi, with pulmonary tuberculosis, suppuration, etc. The laxative type of fever is characterized by significant daily temperature fluctuations (1-2°C). These fluctuations, however, do not reach the norm. Temperature fluctuations during tuberculosis, suppuration, etc. depend on the entry of pyrogenic substances into the bloodstream. When significant amounts of pyrogenic substances enter, the temperature rises, and after a decrease in intake, it decreases.

3. Intermittent fever (febris intermittens) occurs in various forms of malaria, liver diseases, and septic conditions. It is characterized by the correct alternation of short-term attacks of fever with fever-free periods - periods of normal temperature (apyrexia). Intermittent fever is characterized by a rapid, significant increase in temperature that lasts for several hours, as well as a rapid drop to normal values. The period of apyrexia lasts about two (for three-day fever) or three days (for four-day fever).

Types of fever

Then, after the 2nd or 3rd day, an increase in temperature is observed again with the same pattern.

4. Debilitating fever (febris hectica) is characterized by large (3°C or more) rises in temperature with a rapid decrease, sometimes repeating two or three times during the day. Occurs in sepsis, severe tuberculosis, in the presence of cavities and decay of lung tissue. The rise in temperature is associated with the abundant absorption of pyrogenic substances from products of microbial origin and tissue decay.

5. Relapsing fever (febris recurrens) is characterized by alternating periods of increased temperature (pyrexia) with periods of normal temperature (apyrexia), which last for several days. During an attack, temperature rise, fluctuations between the evening rise and morning fall do not exceed 1°C. This temperature curve is typical for relapsing fever. The increase in temperature with this type of fever depends on the entry of spirochetes into the blood, and the period of apyrexia is associated with their disappearance from the blood.

6. Perverted fever (febris inversa) is characterized by perversion
circadian rhythm with higher temperature rises in the morning. Occurs in septic processes, tuberculosis.

7. Atypical fever (febris athypica) occurs in sepsis and is characterized by the absence of certain patterns in fluctuations in body temperature during the day.

Fig.10. Main types of temperature curves

The indicated types of temperature curves do not exhaust their diversity. It should be noted that although temperature curves are to a certain extent specific for different diseases, the type of temperature curve depends both on the form and severity of the disease, and on the reactivity of the body, which in turn is determined by the constitutional and age characteristics of the patient, his immune status, and functional state CNS and endocrine system. The characteristic features of temperature curves have long had diagnostic and prognostic significance. The types of temperature curves today provide the doctor with information about the patient’s condition and have differential diagnostic value. However, with modern methods of treating diseases accompanied by fever, due to the widespread use of antibacterial agents and antibiotics, the doctor does not often see the typical shapes of temperature curves.

Date of publication: 2014-11-02; Read: 10907 | Page copyright infringement

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Fever is a typical protective-adaptive reaction of the body to the action of specific molecules (pyrogens). An increase in body temperature above 37 °C occurs as a result of a temporary restructuring of thermoregulation centers to a new level. Hyperthermia accompanies infectious and oncological diseases and develops as a result of extensive injuries, overheating, and in some cases for unknown reasons. Depending on the nature of the pathological changes, the tactics for managing a febrile patient are chosen.

Origin

Thermoregulatory structures are located in the limbic regions of the central nervous system. In the hypothalamus, there are areas responsible for the perception of information about the temperature level, a set point (“thermal relay”), as well as zones of heat transfer and heat production. Under the influence of biologically active substances, high concentrations of prostaglandin E begin to be produced in the anterior parts of the hypothalamus. An increase in the content of this mediator is a signal for switching the temperature set point to an increased level.

The body begins to readjust to maintain new thermoregulation values. Heat transfer decreases, and heat production increases. After reaching certain indicators, the nervous and endocrine systems continue to maintain the temperature in the given setting range.

There are several triggers that contribute to the appearance of fever:

foreign antigens of bacteria and viruses;
substances produced by tumor cells;
mediators of activated immune representatives, immunoglobulins;
taking certain medications (medicinal low-grade fever);
hormonal disorders (for example, hyperthyroidism);
damage to the hypothalamic region;
overheating.

Meaning of Fever

An increase in temperature within reasonable limits leads to the activation of the body's protective factors. With a fever below 41 °C, metabolic and recovery processes improve. Antibodies and intracellular enzymes work more productively. The movement of macrophages and leukocytes to the area of inflammation or damage is accelerated. In conditions of fever, a more effective response of antibiotics was revealed. There is a post-immunization rise in temperature that accompanies the body's familiarization with the vaccine antigens. The most common post-vaccination fever is post-vaccination fever, reflecting the activity of the production of immunoglobulins against dangerous diseases.

A nonspecific temperature reaction allows for faster and better elimination of the infectious agent and promotes wound healing in the early postoperative period.

However, if the adaptive mechanisms fail, the set point is adjusted to a level of values above 41.1 °C. The condition begins to get out of control. Defense mechanisms are losing ground. A critical situation arises that requires an urgent change in tactics.

State Variability

Fever is classified according to several parameters. Depending on the measured temperature indicators, the following are distinguished:

The nature of the febrile reaction is of particular clinical importance. A rise in temperature accompanied by redness of the skin (red type) is considered favorable. The patient's limbs are hot to the touch. There is increased sweating.

Pale fever with high thermometry readings is a reason to prescribe additional drugs that help change the functioning of thermoregulation. The patient has chills and muscle tremors. A characteristic symptom of such a fever is pallor and coldness of the hands and feet. Body skin is dry and hot. There is a progressive increase in heat production against the background of a significant decrease in heat transfer. The condition may progress to hyperpyretic fever. Young children have an increased risk of rapidly developing a critical situation.

Against the background of intoxication, a person with a high fever often experiences severe headache, heaviness in the eyebrows and pulsation in the temples.

The febrile state has several stages of development. At the very beginning, an increase in temperature to certain values is determined. During this period, thermogenesis increases. At the cellular and tissue level, metabolic processes intensify, the breakdown of proteins, fats and carbohydrates increases. The patient experiences chills, sweating decreases, and blood vessels spasm.

When the values corresponding to the set point are reached, the state stabilizes somewhat. The patient notes fever, weakness, and lethargy. After a natural decrease in the concentration of pyrogens or under the influence of antipyretics, the central nervous system is adjusted to a lower temperature level. The blood is perceived as hot, requiring “cooling”. The fever begins to decline: lytic (smooth) or critical (sharp). At this stage, heat transfer prevails over heat production. The blood vessels dilate and the skin becomes excessively moist. The patient's well-being improves. A previously absent appetite appears.

Types of temperature curves

The rise and fall of temperature can occur repeatedly and be observed over varying periods of time. With regular recording of thermometry indicators, it is possible to identify one of the types of febrile reaction:

Name	Characteristic	A condition in which it occurs
Constant	Daily temperature fluctuations are within 1 °C. Typically 38–39 °C	Acute infectious diseases. Often with pneumonia and ARVI
Laxative (remitting)	Over the course of a day, the temperature ranges from 1 to 2 °C	Purulent pathology
Intermittent (intermittent)	A sudden increase in temperature to 39–40 °C with a sharp decline after a few hours to normal and even subnormal values. Repeats after 1–3 days
Relapsing fever	The temperature rise to high values persists for several days. After a temporary decline, it rises again	Rickettsial diseases. Relapsing fever
Hectic (exhausting, debilitating)	Daily temperature fluctuations are 3–5 °C	Septic conditions
wavy	Gradually increases over several days, then gives the same long decline and repeats	Brucellosis
Incorrect	There is no pattern	Rheumatism. Dysentery
Perverted	The temperature rises mainly in the morning. Night and evening measurements reveal lower readings	Tuberculosis. Prolonged sepsis

Infectious and inflammatory processes, as a rule, are accompanied by a predominance of temperature values in the second half of the day over morning thermometry.

Associated manifestations

A rise in temperature may be preceded by a dry, sore throat. Patients with ARVI experience nasal congestion. The flu condition is accompanied by a feeling of aching joints.

Fever in specific infections develops against the background of characteristic symptoms. Skin rashes and enlargement of different groups of lymph nodes may be present. Hemorrhagic fevers (Ebola, Marburg, etc.) are accompanied by bleeding. In such severe patients, blood leakage from the gums, stomach and intestines, and metrorrhagia are detected.

A rise in temperature is observed with meningitis and encephalitis. Patients attract attention with special postures, specific motor and speech disorders.

Long-term low-grade fever without obvious deviations in health often accompanies tuberculosis, cancer, and endocrine pathology. But there are also benign forms of a slight increase in temperature that cannot be explained.

How can I help you?

The presence of fever below 38–38.5 °C with relatively normal tolerance, which has a clear connection with an acute viral infection, does not require the use of antipyretics. Depending on the patient’s well-being, he is covered with a blanket or unwrapped. Plenty of warm drinks, room ventilation and bed rest are recommended.

If the condition worsens or pyrexia develops, taking Paracetamol or Ibuprofen is indicated (10 mg/kg for children, 1 tablet for adults). If a patient experiences a spasm of peripheral vessels, accompanied by a progression of temperature rise, cold extremities, an antispasmodic is added to the antipyretics (mainly Papaverine, for a child at the rate of 0.1 ml per year of life) under the cover of an antihistamine (Suprastin, Diphenhydramine 0.1 ml/year ). Patient care includes additional physical cooling techniques. Cold is applied through the material near the vessels of the neck and around the head. Rubbing with vodka improves heat transfer from the surface of the skin. A similar scheme is applicable for all types of hyperthermic reactions.

Reducing the temperature during bacterial inflammation is facilitated by the competent use of antibiotics prescribed by a doctor.

The appearance of high thermometry readings in children, lack of response to antipyretic measures and deterioration of the condition for more than three days require seeking specialized help. It must be remembered that the appearance of dangerous symptoms (stellate hemorrhagic rash, shortness of breath, cyanosis, bleeding) becomes a reason to urgently call doctors.

Classification and etiology of fevers

Analysis of the temperature response allows us to assess the height, duration and types of temperature fluctuations, as well as the nature of the accompanying clinical manifestations of the disease.

Types of fevers

The following types of fevers in children are distinguished:

· short-term fever (up to 5-7 days) with a suspected localization, in which the diagnosis can be made on the basis of clinical history and physical findings, with or without laboratory tests;

· fever without a focus, for which the history and physical examination are not suggestive of a diagnosis, but laboratory tests can reveal the etiology;

fever of unknown origin (FUO);

low-grade fever

Feverish reactions are assessed depending on the level of temperature rise, the duration of the febrile period and the nature of the temperature curve.

Types of febrile reactions depending on the degree of increase in body temperature

Only some diseases manifest themselves with characteristic, pronounced temperature curves; however, it is important to know their types for differential diagnosis. It is not always possible to accurately correlate typical changes with the onset of the disease, especially with early antibiotic therapy. However, in some cases, the nature of the onset of fever can suggest a diagnosis. Thus, a sudden onset is characteristic of influenza, meningitis, malaria, subacute (2-3 days) - for typhus, psittacosis, Q fever, gradual - typhoid fever, brucellosis.

Based on the nature of the temperature curve, several types of fevers are distinguished

Persistent fever(febris continua) – temperature exceeds 390C, the differences between morning and evening body temperature are insignificant (maximum 10C). Body temperature remains uniformly high throughout the day. This type of fever occurs in untreated pneumococcal pneumonia, typhoid fever, paratyphoid fever and erysipelas.

Laxative(remitting) fever(febris remittens) – daily temperature fluctuations exceed 10C, and it can drop below 380C, but does not reach normal numbers; observed in pneumonia, viral diseases, acute rheumatic fever, juvenile rheumatoid arthritis, endocarditis, tuberculosis, abscesses.

Intermittent(intermittent) fever(febris intermittens) – daily fluctuations in maximum and minimum temperatures of at least 10C, periods of normal and elevated temperatures often alternate; a similar type of fever is inherent in malaria, pyelonephritis, pleurisy, and sepsis.

Exhaustive, or hectic, fever(febris hectica) - the temperature curve resembles that of a laxative fever, but its daily fluctuations are more than 2-30C; a similar type of fever can occur with tuberculosis and sepsis.

Relapsing fever(febris recurrens) – high fever for 2-7 days, alternating with periods of normal temperature lasting several days. The febrile period begins suddenly and also ends suddenly. A similar type of febrile reaction is observed in relapsing fever and malaria.

Undulating fever(febris undulans) - manifests itself as a gradual increase in temperature from day to day to high numbers, followed by a decrease in it and the repeated formation of individual waves; a similar type of fever occurs with lymphogranulomatosis and brucellosis.

Perverted(inverse) fever(febris inverse) – there is a distortion of the daily temperature rhythm with higher temperature rises in the morning; a similar type of fever occurs in patients with tuberculosis, sepsis, tumors, and is characteristic of some rheumatic diseases.

Incorrect or atypical fever(irregularis or febris atypical) - fever in which there are no patterns of rise and fall in temperature.

Monotonous type of fever - with a small range of fluctuations between morning and evening body temperature;

It should be noted that at present, typical temperature curves are rare, which is associated with the use of etiotropic and antipyretic drugs.

Fever is a general reaction of the body to any irritation, characterized by an increase in body temperature due to a violation of thermoregulation.

Fever(Latin “febris”) is an increase in body temperature that occurs as an active protective-adaptive reaction of the body in response to a variety of pathogenic stimuli.

So, fever is an increase in body temperature caused by disruption and restructuring of thermoregulation processes. Fever is a leading symptom of many infectious diseases.

During fever, heat generation prevails over heat transfer.

The main cause of fever is infection. Bacteria or their toxins, circulating in the blood, cause disruption of thermoregulation. It can be assumed that this disorder also occurs as a reflex from the site of infection.

Various protein substances, so-called foreign proteins, can also cause an increase in body temperature. Therefore, the infusion of blood, serums and vaccines sometimes causes a rise in temperature.

At elevated body temperatures, metabolism increases, and the number of leukocytes often increases. It must be assumed that a febrile state contributes to the formation of immunity in many infectious diseases, creating conditions for more favorable elimination of infection.

Thus, a feverish reaction, like an inflammatory one, should be considered as a reaction of the body’s adaptation to new pathological conditions.

Depending on the type of disease, the strength of the infection and the reactivity of the body, increases in body temperature can be very diverse.

Types of fever according to the degree of rise in body temperature:
- Subfebrile- body temperature 37-38°C
- Febrile (moderate)- body temperature 38-39°C
- Pyretic (high)- body temperature 39-41°C
- Hyperpyretic (excessive)- body temperature more than 41°C - life-threatening, especially in children

Hypothermia is a temperature below 36°C. The nature of the febrile reaction depends not only on the disease that caused it, but also to a large extent on the reactivity of the body. Thus, in elderly people and weakened patients, some inflammatory diseases, such as acute pneumonia, can occur without severe fever. In addition, patients subjectively tolerate fever differently. Some patients experience severe malaise even at low-grade fever, while others tolerate even significant fever quite satisfactorily.

With a long-term course of a febrile illness, different types of fever can be observed according to the nature of fluctuations in body temperature during the day or types of temperature curves. These types of temperature curves, proposed back in the last century, retain a certain diagnostic value today, but not in all cases of febrile diseases. The widespread use of antibacterial and antipyretic drugs, starting from the first days of the disease, leads to the fact that the temperature curve quickly loses the shape that it would retain during the natural course of the disease.

Types of fever according to the nature of fluctuations in body temperature during the day:

1. Persistent fever- fluctuations in body temperature during the day do not exceed 1°C, usually within 38-39°C. This fever is characteristic of acute infectious diseases. With pneumonia and acute respiratory viral infections, body temperature reaches high values quickly - within a few hours, with typhus - gradually, over several days.

2. Remitting, or laxative, fever- prolonged fever with daily fluctuations in body temperature exceeding 1°C (up to 2°C), without decreasing to normal levels. It is characteristic of many infections, focal pneumonia, pleurisy, purulent diseases.

3. Hectic or wasting fever- daily fluctuations in body temperature are very pronounced (3-5 °C) with a drop to normal or subnormal values. Such fluctuations in body temperature can occur several times a day. Hectic fever is characteristic of sepsis, abscesses - ulcers (for example, lungs and other organs), miliary tuberculosis.

4. Intermittent or intermittent fever- body temperature quickly rises to 39-40°C and within a few hours (i.e. quickly) decreases to normal. After 1 or 3 days, the rise in body temperature repeats. Thus, there is a more or less correct change between high and normal body temperature over the course of several days. This type of temperature curve is characteristic of malaria and the so-called Mediterranean fever.

5. Relapsing fever- unlike intermittent fever, a rapidly increased body temperature remains at an elevated level for several days, then temporarily decreases to normal, followed by a new increase, and so on many times. This fever is characteristic of relapsing fever.

6. Perverted Fever- with such a fever, the morning body temperature is higher than the evening. This type of temperature curve is characteristic of tuberculosis.

7.Wrong fever- fever of indefinite duration with irregular and varied daily fluctuations. It is characteristic of influenza and rheumatism.

8.Undulating fever- note the alternation of periods of gradual (over several days) increase in body temperature and its gradual decrease. This fever is characteristic of brucellosis.

Types of fever during illness can alternate or transform into one another. The most severe toxic forms of some infectious diseases, as well as infectious diseases in elderly patients, weakened people, and young children often occur with almost no fever or even hypothermia, which is an unfavorable prognostic sign.

Types of fever by duration:

1. Fleeting - up to 2 hours

2. Acute - up to 15 days

3. Subacute - up to 45 days

4. Chronic - over 45 days

Periods of fever

Fever goes through three periods in its development:

I - period of rising body temperature;

II - period of relative constancy of body temperature;

III - period of decrease in body temperature.

During the first period of fever there is a limitation of heat transfer, as indicated by a narrowing of the blood vessels of the skin and, in connection with this, a limitation of blood flow, a decrease in skin temperature, a decrease or cessation of sweating. At the same time, heat generation increases and gas exchange increases. Usually these phenomena are accompanied by general malaise, chills, nagging muscle pain, and headache.

With the cessation of the rise in body temperature and the transition of fever in the second period heat transfer increases and is balanced with heat production at a new level. Blood circulation in the skin becomes intense, pale skin gives way to hyperemia, and skin temperature rises. The feeling of cold and chills disappear, sweating increases. The patient complains of feeling hot, headache, dry mouth, and restless. Increased breathing (tachypnea), rapid heartbeat (tachycardia) and decreased blood pressure (hypotension) often develop. At the height of fever, confusion, delirium, hallucinations, and subsequent loss of consciousness are sometimes observed.

Third period of fever characterized by a predominance of heat transfer over heat production. The blood vessels of the skin continue to dilate and sweating increases. Depending on the nature of the decrease in body temperature, there are lysis(Greek “lysis” - dissolution) - a slow drop in body temperature over several days and a crisis(Greek “krisis” - turning point) - a rapid drop in body temperature within 5-8 hours. A critical drop in body temperature is accompanied by profuse sweating, general weakness, pale skin, and may develop collapse(acute vascular insufficiency). The most important diagnostic sign of collapse is a drop in blood pressure. Systolic, diastolic and pulse (the difference between systolic and diastolic) pressure decreases. We can talk about collapse when systolic blood pressure decreases to 80 mmHg. Art. and less. A progressive decrease in systolic blood pressure indicates an increase in the severity of collapse. With a lytic decrease in temperature, the patient's condition gradually improves, he sleeps a lot, and his appetite appears.