Thermoregulation pathology. (Lecture 6)

Июль 31, 2022

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Thermoregulation pathology. (Lecture 6)

Содержание

2. Human thermoregulation
3. The sources of heat production Body BMR (Basal Metabolic Rate) Increased Metabolic Rate: muscle activity (shivering);
4. The ways of heat loss Heat conduction to the objects Heat conduction to the air (convection).
5. Thermoregulation mechanisms
6. The causes of fever Primary pyrogens Infectious pyrogens (from bacteria, viruses, protozoa, fungi). polysaccharides and lipopolysaccharides
7. The causes of fever Primary pyrogens Non-infectious pyrogens foreign proteins, lipids or nuclear acids; products of
8. The causes of fever Secondary pyrogens cytokines: IL-1, IL-6, TNF, gamma-interpherone (produced and released by phagocytes)
9. Fever stages Temperature increase stage – stadium incrementi High temperature standing stage – stadium fastigii Temperature
10. Temperature increase stage Secondary pyrogens Thermoregulatory neurons Activation of phospholipase Increased AA metabolism Increased PG E2
11. Heat loss decreases due to: skin periphery vessels constriction sweat secretion inhibition decrease of evaporation. pilomotor
12. Temperature increase stage Peripheral vessels constriction shivering, pilomotor reflex, feeling of cold Irritation of skin cold
13. Temperature increase stage Heat production increases due to: contractive thermogenesis (increased tone of muscles and shivering).
14. High temperature standing stage no further temperature increase heat loss increases (in comparison with 1st stage)
15. The types of temperature curves Febris continua - temperature fluctuation within 1 C0 range (abdominal typhus,
16. The level of temperarure increase Subfebrile temperature up to 38 C Febrile temperature – 38 -
17. Temperature descent stage Decrease of pyrogenic cytokines synthesis Adjusting point of heat regulation center returns to
18. Metabolic changes in fever BMR in the 1st and 2nd fever stage is increased. In the
19. Metabolic changes in fever Water metabolism 1st stage – increased water loss (due to increased diuresis).
20. Changes in organs function in fever Nervous system – insomnia, high irritability, high sensitivity of skin
21. Changes in organs function in fever GIT - loss of appetite, decrease of salivation, decreased secretion
22. The role of fever POSITIVE Bacteriostatic and bactericidal effects on microbes Activation of immune system (innate
23. The causes of hyperthermia Exogenous – hot climate, hot workshops, heat-isolated cloth, air high humidity, insufficient
24. The causes of hyperthermia Endogenous increase of heat production intensive muscular loading pathologic contractive thermogenesis –
25. Hyperthermia compensation stage Increase of heat loss –dilating of skin arterioles, increase of skin temperature, increased
26. Changes in the organism due to body’s temperature 38°C - Sweating. 39°C - Severe sweating, redness
27. Hyperthermia decompensation stage cardiovascular disturbances – progressive tachycardia, decrease of heart stroke volume, microcirculation disorders, increased
28. The biochemical effects of long exposure to high temperature Denaturation of proteins – blocking of all
29. The biochemical effects of long exposure to high temperature Increase of peroxidative oxidation of lipids –
30. Heat stroke manifestation Body temperature >40 C CNS depression (the most important sign of heat stroke).
31. Thermotherapy (pyrotherapy) General thermotherapy - injection of bacterial lipopolysaccride (primary pyrogens). Aims: to increase adaptive and
32. Thermotherapy (pyrotherapy) Local thermotherapy may be used in cancer treatment: tumor cells have difficulty dissipating heat.
33. Differences between fever and hyperthermia
34. Differences between fever and hyperthermia
35. When fever treatment is needed when fever is accompanied with high pyretic temperature (more than 38,5
36. The causes of hypothermia not effective thermoregulation (infants, babies and aged people); too long exposure to
37. Hypothermia compensation stage Behavioral thermoregulation Reduction of heat loss - peripheral blood vessels constriction. Increase of
38. Changes in the organism due to body’s temperature 35°C - Intense shivering, numbness and bluish /
39. Hypothermia decompensation stage slowing of biochemical reactions (inhibition of metabolism); increase of blood viscosity, slowing of
40. Vicious circles during hypothermia Low body temperature Metabolic circle Metabolism inhibition Low heat production
41. Vicious circles during hypothermia Low body temperature Vascular circle Dilation of peripheral vessels Increased heat loss
42. Vicious circles during hypothermia Low body temperature Neuro-muscular circle Decreased excitability of nervous centres Absence of
43. Controlled hypothermia Systemic controlled hypothermia is used in surgical operations on the organs with stopped bloodflow
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Слайд 2

Human thermoregulation

Слайд 3

The sources of heat production
Body BMR (Basal Metabolic Rate)
Increased Metabolic

Rate:
muscle activity (shivering);
effect of thyroxin on the cells;
effects of epinephrine, norepinephrine and sympathetic stimulation on the cells.

Слайд 4

The ways of heat loss
Heat conduction to the objects
Heat conduction to

the air (convection).
Heat irradiation.
Evaporation.

Слайд 5

Thermoregulation mechanisms

Слайд 6

The causes of fever
Primary pyrogens
Infectious pyrogens (from bacteria, viruses, protozoa, fungi).

polysaccharides and lipopolysaccharides of the microbial cell membrane.

Слайд 7

The causes of fever
Primary pyrogens
Non-infectious pyrogens
foreign proteins, lipids or nuclear acids;
products

of tissue decay (burns, mechanical traumas, surgical operations, internal hemorrhages, infarcts, allergic reactions, autoimmune processes, etc.)

Слайд 8

The causes of fever
Secondary pyrogens
cytokines: IL-1, IL-6, TNF, gamma-interpherone (produced

and released by phagocytes)
Pyrogenic cytokines are synthesized in every case of primary pyrogens appearance.

Слайд 9

Fever stages
Temperature increase stage – stadium incrementi
High temperature standing stage –

stadium fastigii
Temperature descent stage -stadium decrementi

Слайд 10

Temperature increase stage
Secondary
pyrogens
Thermoregulatory neurons
Activation of phospholipase
Increased AA metabolism
Increased PG E2

synthesis

Accumulation of cAMP

Decrease of
cold neurons
excitation
threshold

Adjusting point
of thermoregulation
becomes higher

Primary
pyrogens

Слайд 11

Heat loss decreases due to:
skin periphery vessels constriction
sweat secretion inhibition
decrease of

evaporation.
pilomotor reflex - “goose-flesh”

Temperature increase stage

Слайд 12

Temperature increase stage
Peripheral vessels
constriction
shivering,
pilomotor reflex,
feeling of cold
Irritation of skin
cold

receptors

thermoregulation
center
excitation

Activation of heat
production

RIGOR

Слайд 13

Temperature increase stage
Heat production increases due to:
contractive thermogenesis (increased tone of

muscles and shivering).
noncontractive thermogenesis (increased metabolism of inner organs).

Слайд 14

High temperature standing stage
no further temperature increase
heat loss increases

(in comparison with 1st stage)
thermoregulation is normal (heat production and heat loss are in normal balance)

Слайд 15

The types of temperature curves
Febris continua - temperature fluctuation within 1

C0 range (abdominal typhus, croupous pneumonia).

Febris remittens - daily fluctuation exceeds the 1 C0 range, temperature is high (exudative pleuritis).

Febris intermittens - daily fluctuation exceeds the 1 C0 range, temperature may reverse to normal (malaria, infectious endocarditis).

Febris hectica - temperature fluctuation is 3 to 5 degrees (sepsis)

Слайд 16

The level of temperarure increase
Subfebrile temperature up to 38 C
Febrile

temperature – 38 - 39 C
Pyretic temperature –39 - 41C
Hyperpyretic – temperature is higher than 41C

Слайд 17

Temperature descent stage
Decrease of pyrogenic cytokines synthesis
Adjusting point of

heat regulation center returns to the normal physiological level
Heat loss is prevailing
The decrease of fever may be lytical (slow) or critical (fast).

Слайд 18

Metabolic changes in fever
BMR in the 1st and 2nd fever stage

is increased. In the 3rd stage - decreases.
Carbohydrate and lipids metabolism – prevalence of catabolic processes in the 1st and 2nd fever stage. In the 3rd stage – normal.
Protein metabolism is disturbed in the case of long lasting fever – proteolysis will increase.

Слайд 19

Metabolic changes in fever
Water metabolism
1st stage – increased water loss (due

to increased diuresis).
2nd stage - accumulation of water in the organism.
3rd stage - increased water loss (increase of diuresis and sweating)

Слайд 20

Changes in organs function in fever
Nervous system – insomnia, high irritability,

high sensitivity of skin and mucous covers.
Endocrine system – increase of ACTH, catecholamines, TSH, thyroid hormones.
Heart – tachycardia.
Lungs – increased alveolar ventilation and gas diffusion.

Слайд 21

Changes in organs function in fever
GIT - loss of appetite, decrease

of salivation, decreased secretion and motoric functions.
Liver and pancreas - decreased synthesis of digestive enzymes.
Kidneys – increased diuresis in the 1 and 3 stage of fever and accumulation of water in the second stage.

Слайд 22

The role of fever
POSITIVE
Bacteriostatic and bactericidal effects on microbes
Activation

of immune system (innate and specific immunity)
Increased liver function (detoxication, protein and vitamins synthesis)
Active excretion of toxins (due to increased sweating and diuresis).

NEGATIVE
Functional overload of organs (lungs, heart, endocrine glands)
Hypohydration (cholera) and blood hemolysis (malaria) may lead to disturbances of blood clotting
Disturbances of GIT function due to increased level of toxic substances

Слайд 23

The causes of hyperthermia
Exogenous – hot climate, hot workshops, heat-isolated cloth,

air high humidity, insufficient ventilation.
Endogenous disturbances of heat regulation, without pyrogens formation
heat regulation center violations (cerebral traumas, encephalitis, cerebral edema)
fever caused by psychical diseases, nervous excitation, stresses

Слайд 24

The causes of hyperthermia
Endogenous increase of heat production
intensive muscular loading
pathologic

contractive thermogenesis – tetanus spasms.
disconnection of oxidation and phosphorylation processes which increases heat production (poisoning by 2,4-dinitrophenolum, hyperthyroidism).
Endogenous decrease of heat loss
sweat secretion decrease under poisoning by cholinolytic medicines (Atropinum);
skin vessels spasms (adrenimimetic overdose and adrenali increased rejection).

Слайд 25

Hyperthermia compensation stage
Increase of heat loss –dilating of skin arterioles, increase

of skin temperature, increased perspiration.
Changes in organism’s functions:
increase of heart rate and BP;
centralization of bloodflow;
decrease of alveolar ventilation;
decrease of working capacity, weakness, drowse, high irritability.

Слайд 26

Changes in the organism due to body’s temperature
38°C - Sweating.

39°C - Severe sweating, redness of the skin, fast heart rate and breathlessness.
40°C - + Fainting, dehydration, weakness, vomiting, headache and dizziness, profuse sweating.
41°C - + hallucinations, delirium, drowsiness.
42°C - + severe delirium and vomiting, coma, convulsions.
43°C - + serious brain damage, continuous convulsions and shock, cardio-respiratory collapse will occur.
44°C or more - almost certainly death will occur.

Compensation

Decompensation

Слайд 27

Hyperthermia decompensation stage
cardiovascular disturbances – progressive tachycardia, decrease of heart stroke

volume, microcirculation disorders, increased blood clotting.
acidosis due to hypoxia.
hypohydration (du to profound sweating) leads to increased blood viscosity
metabolic violations

Слайд 28

The biochemical effects of long exposure to high temperature
Denaturation of proteins

– blocking of all enzyme pathways
Liquefaction of lipid membrane – destroying cell walls
Damage of mitochondrial membranes - paralysis of energy production
Increase of Na+ leak

Слайд 29

The biochemical effects of long exposure to high temperature
Increase of peroxidative

oxidation of lipids – accumulation of high toxic suboxidized lipid metabolism products
Carbohydrate metabolism and other energy pathways are disrupted.
The loss of energy in the cell reduces normal cellular functions and thermoregulation fails.

Слайд 30

Heat stroke manifestation
Body temperature >40 C
CNS depression (the most important

sign of heat stroke).
bizarre behavior
amnesia
collapse, delirium, stupor, and coma.
The skin color may be ashen, implying circulatory collapse, or pink.
Symptoms of autonomic nervous system dysfunction, miosis, decreased pain response, and dehydration symptoms

Слайд 31

Thermotherapy (pyrotherapy)
General thermotherapy - injection of bacterial lipopolysaccride (primary pyrogens).

Aims:
to increase adaptive and innate immunity in chronic infectious diseases (arthritis, syphilis)
to intensify reparative processes in bones and other tissues after their damage, trauma, surgical operations.

Слайд 32

Thermotherapy (pyrotherapy)
Local thermotherapy may be used in cancer treatment:
tumor cells have

difficulty dissipating heat.
local increase of temperature brake mitoses in cancer cells, cause denaturation of cancer cell membrane proteins.
Even if the cancerous cells do not die, they become more susceptible to ionizing radiation treatments or to certain chemotherapies.

Слайд 33

Differences between fever and hyperthermia

Слайд 34

Differences between fever and hyperthermia

Слайд 35

When fever treatment is needed
when fever is accompanied with high pyretic

temperature (more than 38,5 C);
when fever is observed in the patient with cardio-vascular failure, diabetes mellitus or other endocrine diseases;
in newborns (0-2 months), infants (2 months till 1 year) and aged people.

Слайд 36

The causes of hypothermia
not effective thermoregulation (infants, babies and aged people);
too

long exposure to the cold surroundings;
disturbances of nervous system function (drugs, alcohol, toxic substances, parkinson disease);
disturbances of endocrine system function (hypothyroidism, hypopituitarism, adrenal insufficiency) that lead to decreased heat production.

Слайд 37

Hypothermia compensation stage
Behavioral thermoregulation
Reduction of heat loss - peripheral blood

vessels constriction.
Increase of heat production - activation of bloodflow in inner organs, induction of contractive thermogenesis (shivering).
Heart and lungs: tachycardia, increase of BP and heart stroke volume, increased ventilation of lungs.

Слайд 38

Changes in the organism due to body’s temperature
35°C - Intense shivering,

numbness and bluish / greyness of the skin.
34°C - Severe shivering, loss of movement of fingers, blueness and confusion.
33°C + sleepiness, depressed reflexes, progressive loss of shivering, slow heart beat, shallow breathing.
32°C + Hallucinations, delirium, comatose. Shivering and nervous reflexes are absent.
31°C + shallow breathing and slow heart rate. Possibility of serious heart rhythm problems.
28°C + Severe heart rhythm disturbances, problems with breathing.
24-26°C or less - Death due to irregular heart beat or respiratory arrest.

Compensation

Decompensation

Слайд 39

Hypothermia decompensation stage
slowing of biochemical reactions (inhibition of metabolism);
increase of blood

viscosity, slowing of blood flow, increase of blood coagulation;
development of tissue’s hypoxia.
Cold core temperature (below 250C) causes the depression of brain respiratory, vascular and thermoregulation centers, the violation of heart contraction.

Слайд 40

Vicious circles during hypothermia
Low
body temperature
Metabolic circle
Metabolism
inhibition
Low
heat production

Слайд 41

Vicious circles during hypothermia
Low
body temperature
Vascular circle
Dilation of
peripheral
vessels
Increased
heat loss

Слайд 42

Vicious circles during hypothermia
Low
body temperature
Neuro-muscular circle
Decreased excitability
of nervous centres
Absence of

contractive
thermogenesis

Слайд 43

Controlled hypothermia
Systemic controlled hypothermia is used in surgical operations on

the organs with stopped bloodflow – heart, brain, large vessels.
Cells and tissues in the controlled hypothermia decrease their functional activity.
It prevents disturbances of ABB, water and ion metabolism, increase tissue’s resistance to hypoxia and other pathogenic stimuli.
Local induced hypothermia (brain, kidneys, liver, prostate etc.) is provided complex surgical operations.

Thermoregulation pathology. (Lecture 6)

Содержание

Human thermoregulation

The sources of heat production Body BMR (Basal Metabolic Rate)Increased Metabolic

The ways of heat lossHeat conduction to the objectsHeat conduction to

Thermoregulation mechanisms

The causes of feverPrimary pyrogensInfectious pyrogens (from bacteria, viruses, protozoa, fungi).

The causes of feverPrimary pyrogensNon-infectious pyrogensforeign proteins, lipids or nuclear acids;products

The causes of feverSecondary pyrogens cytokines: IL-1, IL-6, TNF, gamma-interpherone (produced

Fever stagesTemperature increase stage – stadium incrementiHigh temperature standing stage –

Temperature increase stage SecondarypyrogensThermoregulatory neuronsActivation of phospholipaseIncreased AA metabolismIncreased PG E2

Heat loss decreases due to:skin periphery vessels constrictionsweat secretion inhibitiondecrease of

Temperature increase stagePeripheral vesselsconstrictionshivering, pilomotor reflex,feeling of coldIrritation of skin cold

Temperature increase stageHeat production increases due to:contractive thermogenesis (increased tone of

High temperature standing stage no further temperature increase heat loss increases

The types of temperature curvesFebris continua - temperature fluctuation within 1

The level of temperarure increaseSubfebrile temperature up to 38 C Febrile

Temperature descent stage Decrease of pyrogenic cytokines synthesis Adjusting point of

Metabolic changes in feverBMR in the 1st and 2nd fever stage

Metabolic changes in feverWater metabolism1st stage – increased water loss (due

Changes in organs function in feverNervous system – insomnia, high irritability,

Changes in organs function in feverGIT - loss of appetite, decrease

The role of feverPOSITIVE Bacteriostatic and bactericidal effects on microbes Activation

The causes of hyperthermiaExogenous – hot climate, hot workshops, heat-isolated cloth,

The causes of hyperthermiaEndogenous increase of heat production intensive muscular loadingpathologic

Hyperthermia compensation stageIncrease of heat loss –dilating of skin arterioles, increase

Changes in the organism due to body’s temperature 38°C - Sweating.

Hyperthermia decompensation stagecardiovascular disturbances – progressive tachycardia, decrease of heart stroke

The biochemical effects of long exposure to high temperatureDenaturation of proteins

The biochemical effects of long exposure to high temperatureIncrease of peroxidative

Heat stroke manifestationBody temperature >40 C CNS depression (the most important

Thermotherapy (pyrotherapy) General thermotherapy - injection of bacterial lipopolysaccride (primary pyrogens).

Thermotherapy (pyrotherapy)Local thermotherapy may be used in cancer treatment:tumor cells have

Differences between fever and hyperthermia

Differences between fever and hyperthermia

When fever treatment is neededwhen fever is accompanied with high pyretic

The causes of hypothermianot effective thermoregulation (infants, babies and aged people);too

Hypothermia compensation stageBehavioral thermoregulation Reduction of heat loss - peripheral blood

Changes in the organism due to body’s temperature35°C - Intense shivering,

Hypothermia decompensation stageslowing of biochemical reactions (inhibition of metabolism);increase of blood

Vicious circles during hypothermiaLow body temperatureMetabolic circleMetabolism inhibitionLow heat production

Vicious circles during hypothermiaLow body temperatureVascular circleDilation of peripheralvesselsIncreased heat loss

Vicious circles during hypothermiaLow body temperatureNeuro-muscular circleDecreased excitabilityof nervous centresAbsence of

Controlled hypothermia Systemic controlled hypothermia is used in surgical operations on

Похожие презентации

The sources of heat production
Body BMR (Basal Metabolic Rate)
Increased Metabolic

The ways of heat loss
Heat conduction to the objects
Heat conduction to

The causes of fever
Primary pyrogens
Infectious pyrogens (from bacteria, viruses, protozoa, fungi).

The causes of fever
Primary pyrogens
Non-infectious pyrogens
foreign proteins, lipids or nuclear acids;
products

The causes of fever
Secondary pyrogens
cytokines: IL-1, IL-6, TNF, gamma-interpherone (produced

Fever stages
Temperature increase stage – stadium incrementi
High temperature standing stage –

Temperature increase stage
Secondary
pyrogens
Thermoregulatory neurons
Activation of phospholipase
Increased AA metabolism
Increased PG E2

Heat loss decreases due to:
skin periphery vessels constriction
sweat secretion inhibition
decrease of

Temperature increase stage
Peripheral vessels
constriction
shivering,
pilomotor reflex,
feeling of cold
Irritation of skin
cold

Temperature increase stage
Heat production increases due to:
contractive thermogenesis (increased tone of

High temperature standing stage
no further temperature increase
heat loss increases

The types of temperature curves
Febris continua - temperature fluctuation within 1

The level of temperarure increase
Subfebrile temperature up to 38 C
Febrile

Temperature descent stage
Decrease of pyrogenic cytokines synthesis
Adjusting point of

Metabolic changes in fever
BMR in the 1st and 2nd fever stage

Metabolic changes in fever
Water metabolism
1st stage – increased water loss (due

Changes in organs function in fever
Nervous system – insomnia, high irritability,

Changes in organs function in fever
GIT - loss of appetite, decrease

The role of fever
POSITIVE
Bacteriostatic and bactericidal effects on microbes
Activation

The causes of hyperthermia
Exogenous – hot climate, hot workshops, heat-isolated cloth,

The causes of hyperthermia
Endogenous increase of heat production
intensive muscular loading
pathologic

Hyperthermia compensation stage
Increase of heat loss –dilating of skin arterioles, increase

Changes in the organism due to body’s temperature
38°C - Sweating.

Hyperthermia decompensation stage
cardiovascular disturbances – progressive tachycardia, decrease of heart stroke

The biochemical effects of long exposure to high temperature
Denaturation of proteins

The biochemical effects of long exposure to high temperature
Increase of peroxidative

Heat stroke manifestation
Body temperature >40 C
CNS depression (the most important

Thermotherapy (pyrotherapy)
General thermotherapy - injection of bacterial lipopolysaccride (primary pyrogens).

Thermotherapy (pyrotherapy)
Local thermotherapy may be used in cancer treatment:
tumor cells have

When fever treatment is needed
when fever is accompanied with high pyretic

The causes of hypothermia
not effective thermoregulation (infants, babies and aged people);
too

Hypothermia compensation stage
Behavioral thermoregulation
Reduction of heat loss - peripheral blood

Changes in the organism due to body’s temperature
35°C - Intense shivering,

Hypothermia decompensation stage
slowing of biochemical reactions (inhibition of metabolism);
increase of blood

Vicious circles during hypothermia
Low
body temperature
Metabolic circle
Metabolism
inhibition
Low
heat production

Vicious circles during hypothermia
Low
body temperature
Vascular circle
Dilation of
peripheral
vessels
Increased
heat loss

Vicious circles during hypothermia
Low
body temperature
Neuro-muscular circle
Decreased excitability
of nervous centres
Absence of

Controlled hypothermia
Systemic controlled hypothermia is used in surgical operations on