Temperature practical cum theory part by Pandian M, From DYPMCKOP. This PPT f...Pandian M
INTRODUCTION
HOMEOTHERMIC ANIMALS
POIKILOTHERMIC ANIMALS
BODY TEMPERATURE
Normal Body Temperatures
VARIATIONS OF BODY TEMPERATURE
Pathological Variations
HEAT GAIN OR HEAT PRODUCTIONIN THE BODY
HEAT LOSS FROM THE BODY
Regulation of Body Temperature
Hypothalamus has two centers which regulate the body temperature:
Applied
Body temperature by Pandian M, Tutor Dept of Physiology, DYPMCKOP, this PPT f...Pandian M
BODY TEMPERATURE
HEAT BALANCE
Mechanisms of heat gain
Mechanisms of heat loss
VARIATIONS OF BODY TEMPERATURE
REGULATION OF BODY TEMPERATURE
Thermoreceptors
Hypothalamus: the thermostat
Thermoregulatory effector mechanisms
ABNORMALITIES OF BODY TEMPERATURE
Temperature practical cum theory part by Pandian M, From DYPMCKOP. This PPT f...Pandian M
INTRODUCTION
HOMEOTHERMIC ANIMALS
POIKILOTHERMIC ANIMALS
BODY TEMPERATURE
Normal Body Temperatures
VARIATIONS OF BODY TEMPERATURE
Pathological Variations
HEAT GAIN OR HEAT PRODUCTIONIN THE BODY
HEAT LOSS FROM THE BODY
Regulation of Body Temperature
Hypothalamus has two centers which regulate the body temperature:
Applied
Body temperature by Pandian M, Tutor Dept of Physiology, DYPMCKOP, this PPT f...Pandian M
BODY TEMPERATURE
HEAT BALANCE
Mechanisms of heat gain
Mechanisms of heat loss
VARIATIONS OF BODY TEMPERATURE
REGULATION OF BODY TEMPERATURE
Thermoreceptors
Hypothalamus: the thermostat
Thermoregulatory effector mechanisms
ABNORMALITIES OF BODY TEMPERATURE
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different.
Have you ever wondered why you sweat when you get too hot from running or shiver on a cold winter's day in this video we are going to explain why your body behaves like this.
Humans are endotherms and this means we are warm blooded we keep our body operating at thirty seven degrees Celsius regardless of the external conditions however this is a real challenge as our environment changes all the time depending on the weather, our clothes, if we are inside by the fire or outside having a snowball fight. So how does this work?
It's quite similar to the heating system in a house. in a house is a thermostat that measures the temperature if the house gets cold the thermostat will tell the radiators to turn on and heat it up if it's too hot they will be told to switch off simple.
Your body works in just the same way here in your brain as a special area called the hypothalamus and it measures the temperature of the blood flowing through it and also it collects information from temperatures senses around the body. it then decides if the temperature is too hot or too cold and we'll try and bring it back to thirty seven degrees Celsius. If you are too hot the hypothalamus can then send signals out to the body by the nervous system that can cause barriers to fact. It can send a signal to your skin and cool sweat glands to secrete the sweat on to the surface of the skin the sweat itself is not cold but it works because it takes the heat away from your body in order to evaporate it.
Another way of losing is vasodilation let kind of these blood vessels narrows this. That said the skin open white and allow blood to flow through them. They heat is radiated from the blood into the air and the blood cools down. If you get too cold you can do the opposite with these blood vessels and place them on keeping the blood away from the surface of the skin this is called vasoconstriction this is when your muscles contract in order to make. Another fact you may have noticed when you are cold against them. If you look more place the at least the Bulls what you realized is that each of the little bugger has a has to hit out at.
These has stood up on and struck a layer of air around the skin air is a fantastic insulate of heat and this will keep you nice and warm.
Patho-physiology of Fever : Dr Faisal AbdullahFaisal Abdullah
Find the lecture on Approach to a patient with Fever (in Bangla) by Dr. Faisal Abdullah. This Powerpoint presentation describes the mechanism of Fever, How body temperature is maintained, Normal body temperature, Concept of Set Point, Role of pyrogens etc. The difference between Fever, Hyperpyrexia & Hyperthermia is clearly explained here.
https://youtu.be/uqqIH6OfX4o
For any queries, please contact:
faisalabdullah@platform-med.org
facebook.com/faisalization.17
youtube.com/faisalization
faisalization.wordpress.com
Fever is an elevation of body temperature that exceeds
normally daily variation and occurs in conjunction with an
increase in the hypothalamic set point for e.g. 37⁰C-
39⁰C.
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Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different.
Have you ever wondered why you sweat when you get too hot from running or shiver on a cold winter's day in this video we are going to explain why your body behaves like this.
Humans are endotherms and this means we are warm blooded we keep our body operating at thirty seven degrees Celsius regardless of the external conditions however this is a real challenge as our environment changes all the time depending on the weather, our clothes, if we are inside by the fire or outside having a snowball fight. So how does this work?
It's quite similar to the heating system in a house. in a house is a thermostat that measures the temperature if the house gets cold the thermostat will tell the radiators to turn on and heat it up if it's too hot they will be told to switch off simple.
Your body works in just the same way here in your brain as a special area called the hypothalamus and it measures the temperature of the blood flowing through it and also it collects information from temperatures senses around the body. it then decides if the temperature is too hot or too cold and we'll try and bring it back to thirty seven degrees Celsius. If you are too hot the hypothalamus can then send signals out to the body by the nervous system that can cause barriers to fact. It can send a signal to your skin and cool sweat glands to secrete the sweat on to the surface of the skin the sweat itself is not cold but it works because it takes the heat away from your body in order to evaporate it.
Another way of losing is vasodilation let kind of these blood vessels narrows this. That said the skin open white and allow blood to flow through them. They heat is radiated from the blood into the air and the blood cools down. If you get too cold you can do the opposite with these blood vessels and place them on keeping the blood away from the surface of the skin this is called vasoconstriction this is when your muscles contract in order to make. Another fact you may have noticed when you are cold against them. If you look more place the at least the Bulls what you realized is that each of the little bugger has a has to hit out at.
These has stood up on and struck a layer of air around the skin air is a fantastic insulate of heat and this will keep you nice and warm.
Patho-physiology of Fever : Dr Faisal AbdullahFaisal Abdullah
Find the lecture on Approach to a patient with Fever (in Bangla) by Dr. Faisal Abdullah. This Powerpoint presentation describes the mechanism of Fever, How body temperature is maintained, Normal body temperature, Concept of Set Point, Role of pyrogens etc. The difference between Fever, Hyperpyrexia & Hyperthermia is clearly explained here.
https://youtu.be/uqqIH6OfX4o
For any queries, please contact:
faisalabdullah@platform-med.org
facebook.com/faisalization.17
youtube.com/faisalization
faisalization.wordpress.com
Fever is an elevation of body temperature that exceeds
normally daily variation and occurs in conjunction with an
increase in the hypothalamic set point for e.g. 37⁰C-
39⁰C.
263778731218 Abortion Clinic /Pills In Harare ,sisternakatoto
263778731218 Abortion Clinic /Pills In Harare ,ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group ABORTION WOMEN’S CLINIC +27730423979 IN women clinic we believe that every woman should be able to make choices in her pregnancy. Our job is to provide compassionate care, safety,affordable and confidential services. That’s why we have won the trust from all generations of women all over the world. we use non surgical method(Abortion pills) to terminate…Dr.LISA +27730423979women Clinic is committed to providing the highest quality of obstetrical and gynecological care to women of all ages. Our dedicated staff aim to treat each patient and her health concerns with compassion and respect.Our dedicated group of receptionists, nurses, and physicians have worked together as a teamof receptionists, nurses, and physicians have worked together as a team wwww.lisywomensclinic.co.za/
Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Ve...kevinkariuki227
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
TEST BANK for Operations Management, 14th Edition by William J. Stevenson, Verified Chapters 1 - 19, Complete Newest Version.pdf
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
These lecture slides, by Dr Sidra Arshad, offer a quick overview of physiological basis of a normal electrocardiogram.
Learning objectives:
1. Define an electrocardiogram (ECG) and electrocardiography
2. Describe how dipoles generated by the heart produce the waveforms of the ECG
3. Describe the components of a normal electrocardiogram of a typical bipolar leads (limb II)
4. Differentiate between intervals and segments
5. Enlist some common indications for obtaining an ECG
Study Resources:
1. Chapter 11, Guyton and Hall Textbook of Medical Physiology, 14th edition
2. Chapter 9, Human Physiology - From Cells to Systems, Lauralee Sherwood, 9th edition
3. Chapter 29, Ganong’s Review of Medical Physiology, 26th edition
4. Electrocardiogram, StatPearls - https://www.ncbi.nlm.nih.gov/books/NBK549803/
5. ECG in Medical Practice by ABM Abdullah, 4th edition
6. ECG Basics, http://www.nataliescasebook.com/tag/e-c-g-basics
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Title: Sense of Taste
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the structure and function of taste buds.
Describe the relationship between the taste threshold and taste index of common substances.
Explain the chemical basis and signal transduction of taste perception for each type of primary taste sensation.
Recognize different abnormalities of taste perception and their causes.
Key Topics:
Significance of Taste Sensation:
Differentiation between pleasant and harmful food
Influence on behavior
Selection of food based on metabolic needs
Receptors of Taste:
Taste buds on the tongue
Influence of sense of smell, texture of food, and pain stimulation (e.g., by pepper)
Primary and Secondary Taste Sensations:
Primary taste sensations: Sweet, Sour, Salty, Bitter, Umami
Chemical basis and signal transduction mechanisms for each taste
Taste Threshold and Index:
Taste threshold values for Sweet (sucrose), Salty (NaCl), Sour (HCl), and Bitter (Quinine)
Taste index relationship: Inversely proportional to taste threshold
Taste Blindness:
Inability to taste certain substances, particularly thiourea compounds
Example: Phenylthiocarbamide
Structure and Function of Taste Buds:
Composition: Epithelial cells, Sustentacular/Supporting cells, Taste cells, Basal cells
Features: Taste pores, Taste hairs/microvilli, and Taste nerve fibers
Location of Taste Buds:
Found in papillae of the tongue (Fungiform, Circumvallate, Foliate)
Also present on the palate, tonsillar pillars, epiglottis, and proximal esophagus
Mechanism of Taste Stimulation:
Interaction of taste substances with receptors on microvilli
Signal transduction pathways for Umami, Sweet, Bitter, Sour, and Salty tastes
Taste Sensitivity and Adaptation:
Decrease in sensitivity with age
Rapid adaptation of taste sensation
Role of Saliva in Taste:
Dissolution of tastants to reach receptors
Washing away the stimulus
Taste Preferences and Aversions:
Mechanisms behind taste preference and aversion
Influence of receptors and neural pathways
Impact of Sensory Nerve Damage:
Degeneration of taste buds if the sensory nerve fiber is cut
Abnormalities of Taste Detection:
Conditions: Ageusia, Hypogeusia, Dysgeusia (parageusia)
Causes: Nerve damage, neurological disorders, infections, poor oral hygiene, adverse drug effects, deficiencies, aging, tobacco use, altered neurotransmitter levels
Neurotransmitters and Taste Threshold:
Effects of serotonin (5-HT) and norepinephrine (NE) on taste sensitivity
Supertasters:
25% of the population with heightened sensitivity to taste, especially bitterness
Increased number of fungiform papillae
2. Introduction
• The normal body temperature range is 97°F (36°C) to 99°F (37.4°C) i.e. on an
average 98.8°F (37°C) when measured orally by a thermometer (0.5-1°F higher
if measured rectally).
• This body temperature is actually the core temperature which remains
constant except for when the person is suffering from febrile illness.
• There is also the skin temperature which in contrast to the core rises and falls
with the temperature of the surroundings.
• The temperature of the scrotum is as carefully regulated at 32°C.
3. Why is temperature regulation necessary?
• As we are warm blooded animals, the body temperature remains
within a limited constant value 37°C (±1°C).
• The internal temperature is independent of the environmental
temperature.
• Body maintains this temperature because-
• Speed of reactions in our body varies with temperature
• Enzymes in our body have a narrow range for optimum
functioning.
4. The body (core) temperature homeostasis is
controlled by balancing heat gain and the heat loss.
5. Heat Gain
Heat can be gained from the surrounding by radiation and conduction.
It can also be produced as a by-product of metabolism.
Main factors for production are -
• BMR of all the cells of the body.
• Hormonal effect, mainly by Thyroxin (to lesser extent by GH and testosterone).
• extra rate of metabolism due to muscle activity and work.
• extra rate of metabolism for food digestion, absorption and storage.
• sympathetic stimulation by the effect of epinephrine and norepinephrine.
6. Heat Loss
• Heat is primarily lost from the exposed body surface.
• Body heat is lost by-
• Radiation ~ 70%
• Vaporization of sweat ~27%
• Respiration ~2%
• Urination and defecation ~1%
7. Role Of Hypothalamus
• The temperature of the body is regulated almost entirely by nervous
feedback mechanisms.
• The anterior hypothalamic-preoptic area contains large numbers of
heat-sensitive neurons, as well as about one-third as many cold-
sensitive neurons.
• The heat-sensitive neurons increase their firing rate 2 to 10 fold in
response to a 10°C increase in body temperature.
• When the preoptic area is heated, the skin all over the body sweats
profusely, whereas the skin blood vessels become greatly dilated.
• Any excess heat production is also inhibited.
8. • Additional peripheral temperature receptors are present in the skin and in a
few specific deep tissues (the spinal cord, abdominal viscera, and in or around
the great veins) of the body.
• Deep receptors function differently from the skin receptors because they are
exposed to the body core temperature rather than the body surface
temperature. Yet, both temperature receptors, detect mainly cold rather than
warmth.
• It is probable that peripheral receptors are concerned primarily with preventing
hypothermia.
• The temperature sensory signals from the central and the peripheral receptors
are transmitted into posterior hypothalamus for integration and regulation.
9. Temperature-Decreasing Mechanisms When the Body Is Too Hot
• Vasodilation
• Sweating
• Decrease in thermogenesis
Temperature-Increasing Mechanisms When the Body Is Too Cold
• Vasoconstriction
• Piloerection
• Increased in thermogenesis
• Increased secretion of Epinephrine
10. Thermogenesis
• Heat production by the body to increase the temperature.
• By following means-
1. Shivering thermogenesis
2. Chemical or Nonshivering thermogenesis
a) Brown fat
b) Thyroxin (Long term)
11. Brown Fat
• Also known as brown adipose tissue (BAT).
• It produces heat to help maintain the body temperature in cold
conditions.
• It contains special mitochondria where uncoupled oxidation occurs.
• It is richly supplied with sympathetic nerves that release
norepinephrine, which causes expression of mitochondrial
uncoupling protein 1 (UCP1, also called thermogenin) and increases
thermogenesis.
• Most abundant in infants and decreases with age.
12. Thyroxine
• Cooling the anterior hypothalamic-preoptic area also increases
production of thyrotropin-releasing hormone by the hypothalamus.
• This stimulates anterior pituitary to produce TSH, which acts on Thyroid
to produce Thyroxine.
• This increased amount of thyroxine activates uncoupling protein and
causes thermogenesis.
• This increase in metabolism does not occur immediately but requires
long term (weeks) exposure to cold to make the thyroid gland
hypertrophy and reach its new level of thyroxine secretion.
13. Temperature elevated by as much as 0.5°C when the metabolic rate is
high, as in hyperthyroidism, and lowered when the metabolic rate is
low, as in hypothyroidism
14. Set Point for temperature control
• The critical body core temperature i.e. 37°C (98.8°F) is called the “set
point”.
• All the temperature control mechanisms continually attempt to bring
the body temperature back to this set point level.
• Temperature signals from the peripheral receptors, also contribute
slightly to body temperature regulation by altering the set point of
the hypothalamic temperature control center.
15.
16. When the skin temperature is high, sweating begins at a lower hypothalamic
temperature than normal i.e. set point changes.
17. A 16-year-old high school student is brought to the emergency department
after being found lying in the front yard of a neighbour’s house, where he was
mowing the lawn. The patient has a part-time yard service and has been
mowing for several months without problems. The patient was finishing his
sixth yard for the day during a summer month with temperatures exceeding
100°F. His mowing partner noticed that the patient had been complaining of
fatigue, light-headedness, nausea, and profuse sweating in the previous yard.
While mowing the last yard, he became very confused and behaved oddly
before finally losing consciousness. In the emergency department, he is
tachycardic, with a temperature of 106°F. He is lethargic, and his skin is dry.
Case
18. Heatstroke
It is the most severe form of hyperthermia in which body temperature
rises beyond the critical range upto 105-108°F.
Symptoms include-
1. Dizziness
2. Abdominal distress
3. Delirium
4. Loss of consciousness (eventually)
These symptoms are often worsened by a degree of circulatory shock due
to excessive loss of fluid and electrolyte in sweat.
19. Fever
Increase in body temperature due to chemical substances that affect the
hypothalamus from an infection or due to abnormality (lesion) in the brain.
Fever due to brain lesions
Also know as non infectious fever.
Any brain tumor that compresses the hypothalamus can affect regulation.
In NICUs whenever a surgeon operates in the region of hypothalamus, severe
fever almost always sets in.
More frequent in patients with Subarachnoid haemorrhage.
20. Infectious fever and its Mechanism of action
Substances that cause rise in temperature of the body are called pyrogens.
Bacteria and its breakdown substances
(lipopolysaccharide toxin) in body fluid
Phagocytosis by neutrophils,
macrophages and killer lymphocytes
Release of cytokines after digestion
mainly interleukin-1 (IL-1)
Formation of prostaglandins mainly
PGE2 which acts on Hypothalamus
21. Since at higher temperature the activity of infection causing micro-organism is
reduced and antibody production is increased therefore hypothalamus raises
the value of set point.
Once the set point value increases all the mechanisms for raising the body
temperature by heat conservation and increased heat production become
active.
Fever above 105°F can extremely harmful as it causes local haemorrhages
and cellular degeneration, specially to the brain.
Antipyretic drugs like Aspirin and Ibuprofen reduce/prevent fever by impeding
the formation of prostaglandins from arachidonic acid
22. Hypothermia
• The ability of the hypothalamus to regulate temperature is greatly
impaired when the body temperature falls below about 94°F.
• At rectal temperatures of about 82.5°F (28°C), the ability to
spontaneously return the temperature to normal is lost.
• The individual continues to survive and if rewarmed with external
heat, returns to a normal state.
23. Artificial Hypothermia
• Used during heart surgery so that the heart can be stopped
artificially for many minutes at a time.
• First there is administration of a strong sedative to depress the
reactivity of the hypothalamic temperature controller.
• Then cooling the person with ice or cooling blankets until the
temperature falls.
• Cooling to this extent does not cause tissue damage, but it does
slow the heart and greatly depresses cell metabolism.