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DANYLO HALYTSKYI LVIV NATIONAL MEDICAL UNIVERSITY
DEPARTMENT OF PATHOPHYSIOLOGY
Methodical guide
for individual study of English speaking students of Medical Faculty for
preparing to practical classes on the theme
“HYPOXIAS”
on the discipline “Pathological Physiology”
Lviv - 2014
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DANYLO HALYTSKYI LVIV NATIONAL MEDICAL UNIVERSITY
DEPARTMENT OF PATHOPHYSIOLOGY
Methodical guide
for individual study of English speaking
students of Medical Faculty
for preparing to practical classes on the theme
“HYPOXIAS”
Subject
Module # 2
Thematic module # 2
Year of study
Faculty
Pathological Physiology
Pathology organs and systems
Pathology of organs and systems
3
Medical
Lviv - 2014
2
Methodical guide
has been complited by: prof. Regeda M. S., as prof.
Kachmarska M.O.,ass. Sementsiv N.G., ass. Baida M.L., ass. Kolichetska M,A.
In the methodical guide for individual study for English speaking students of
Medical Faculty for preparing to practical classes on the theme “Hypoxias”
containst basic theoretical information in full volume and according to the
curriculum educational “Pathological Physiology”.
Responsible for edition:
First vice-rector on scientific-and-academic work
of Danylo Halytski Lviv National Medical University
acad. Gzhegotsky M.R.
Reviewed by :
Associate professor
of the department of Pathological Anatomy
with the course of Forensic Medicine
of Danylo Halytskyi Lviv National Medical University
Vovk V.I.
Associate professor
of the department of Pharmacology
of Danylo Halytskyi Lviv National Medical University
Havryluk I.M.
Associate professor
head of the department of Foreign languages
of Danylo Halytskyi Lviv National Medical University
Isayeva O.S.
Approved and recommended for publication at the sitling of the Cycle Methodical
Commission in
Danylo Halytskyi Lviv National Medical University
Protocol 2 2014
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HYPOXIAS
I. ACTUALITY OF THE THEME
Tissue breathing is a process of consumption of oxygen by tissues. In providing
tissues with oxygen the following systems participate: cardiovascular, blood and
the apparatus of external breathing. Hence, violations which happen in these
systems reflect on the functions of tissue breathing. At the same time violation of
functioning one system is compensated by increasing functioning of the other one.
At deficiency of compensatory reactions and at violation of abilities of tissues to
utilize oxygen hypoxia arises. Hypoxia is an oxygen tissue starving, a state, which
emerges in the organism as a result of violation of oxygen delivery to tissues and
assimilation of it in tissues.
Division of hypoxias into hypoxic, breathing, circulating, bloody, tissue and mixed
reflects a vast circle of diseases, at which it can develop. Study of the pathogenesis
of hypoxias, adaptive-protective mechanisms and pathological changes at it is
essential for choosing pathogenetic therapy of hypoxic states.
II. STUDY AIM
1. To know general conformities to law of the arising, development, and
finishing of hypoxic states.
2. To be able to divide adaptive-compensatory phenomena at hypoxia and
adaptation in the system of oxygen utilization and its transporting.
3. On experimental models to assess state of reactivity of the organism, initial
level of metabolic processes in endurance of the organism in the terms of
oxygen starving.
4. To know that professional poisonings may be the reason of oxygen starving.
III. BASIC KNOWLEDGE AND SKILLS FOR PREPARATION TO THE
TOPIC (interdisciplinary integration)
Disciplines
Knowledge acquired
Structure of cell, tissues, tissue
breathing
Histological structure of respiratory
organs, heart, and blood
Anatomical structure of respiratory,
cardio-vascular systems and blood
Functions of the respiratory, cariovascular systems and blood
Biology
Histology
Normal Anatomy
Normal physiology
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IV. TASKS FOR SELF-PREPARATION
1. List of main concepts, parameters, characteristics, which a student must
master during preparation to a lesson
Concept
Definition
This is a typical pathological process,
which arises due to insufficient supply
of oxygen to tissues or as a result of its
insufficient utilization by tissues
This is an oxygen deprivation that arises
due to decrease partial oxygen pressure
in the air inhaled
This is an oxygen deprivation due to
disorder of haemodynamics or abnormal
local circulation
This is an oxygen deprivation due to
decrease in oxygen capacity in the blood
This is an oxygen deprivation that
emerges as a result of abnormal oxygen
utilization by cells
This is an oxygen deprivation due to
increased functional load
Hypoxia
Hypoxic hypoxia
Circulatory hypoxia
Blood hypoxia
Tissue hypoxia
Load hypoxia
2. Theoretical questions to lesson
1. Principles of hypoxic states classification.
2. Mechanisms of development of hypoxia.
3. Etiology and pathogenesis of hypoxic hypoxia.
4. Etiology and pathogenesis of breathing hypoxia.
5. Etiology and pathogenesis of circulating hypoxia.
6. Etiology and pathogenesis of bloody hypoxia.
7. Etiology and pathogenesis of tissue hypoxia.
8. Immediate and long-lasting adaptive reactions of the organism at hypoxia.
9. Mechanism of hypoxic injury of cell.
10.Oxygen therapy and toxic properties of oxygen. Hyperbaric oxygenation.
11.Resistance of some organs and tissues to hypoxia.
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3. Practical work (tasks) performed during practical lesson
#
1.
2.
Task
To reproduce in
experiment hypoxia at
frog
Indications to the task
Fix and form the results
of the experiment. Make
conclusions.
To reproduce in an
experiment on rats
model of acute cardiolungs insufficiency
Draw and describe shortly the changes, which are
observed.
Write down in a protocol the results received.
Fix and form the results
of the experiment. Make
conclusions.
Insert 3 ml of 10% solution of Na nitrate under the
skin of frog’s back. Perform dissection of thoracic
and abdominal cavities. Dissect the heart.
Inject 1 ml of 0.1% solution of adrenalin
intraabdominally to a rat. Observe after development
of cardio-lungs insufficiency
Draw and shortly describe the picture observed.
Write down in a protocol the results received.
Orientation chart for organization of students’ independent work with
educational literature
# Task
Indications to the task
1 Mechanisms of the
Indicate properties
development of
metabolism violation
during hypoxias
2
Ways of pharmacological
correction of the
breathing insufficiency
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Treatment:
Entering of oxygen
Stimulation of the systems of
oxygen transporting
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Compensation-adaptive reactions
In systems of oxygen
utilization
Specific antihypoxic cures
Intoxication with products of
metabolism
Glycolysis
Violations of matters
exchange
Stimulation of the systems of oxygen utilization
Bloody
Activation of freeradical oxidization
Disconnection of
oxidization and
phosphorylation
Inactivation of
tissue enzymes
As a result of
hemoglobin
deactivation
Anemic
Violation of
perfusion
Ischemic
Violation of
diffusion
ation
Breathing
Metabolic acidosis
Deficiency of energy
Strengthening of
glycolysis
Fight for O2
Increased number of
mitochondria
In systems of oxygen
transportation
Oxyhemoglobin
dissociation
Violation of
perfusion
Violation of
ventilation
Breathing with the
air with an
increased contents
of O2
Hypoxic
Activation of
breathing enzymes
Pathogenesis:
Oxyhemoglobin
dissociation
Polycythemia
Etiology:
Climbing on height
Types:
Increasing of blood
circulation
Hyperventilation
V. CONTENT OF THE TOPIC
Structurally-logical scheme of the theme’s content
HYPOXIA
Tissue
Pathological violations
Violations in organs and
systems
PATHOPHYSIOLOGY SINGS AND SYMPTOMS OF HYPOXIA
After mixing with water vapor and expired CO2 in the lungs, oxygen
diffuses down a pressure gradient to enter arterial blood where its partial pressure
is around 100 mmHg (13.3 kPa). Arterial blood flow delivers oxygen to the
peripheral tissues, where it again diffuses down a pressure gradient into the cells
and into their mitochondria. These bacteria-like cytoplasmic structures strip
hydrogen from fuels (glucose, fats and some amino acids) to burn with oxygen to
form water. The fuel's carbon is oxidized to CO2, which diffuses down its partial
pressure gradient out of the cells into venous blood to be exhaled finally by the
lungs. Experimentally, oxygen diffusion becomes rate limiting (and lethal) when
arterial oxygen partial pressure falls to 40 mmHg (5.3 kPa) or below.
If oxygen delivery to cells is insufficient for the demand (hypoxia),
hydrogen will be shifted to pyruvic acid converting it to lactic acid. This temporary
measure (anaerobic metabolism) allows small amounts of energy to be released.
Lactic acid build up (in tissues and blood) is a sign of inadequate mitochondrial
oxygenation, which may be due to hypoxemia, poor blood flow (e.g., shock) or a
combination of both.] If severe or prolonged it could lead to cell death.
The symptoms of generalized hypoxia depend on its severity and
acceleration of onset. In the case of altitude sickness, where hypoxia develops
gradually, the symptoms include headaches, fatigue, shortness of breath, a feeling
of euphoria and nausea. In severe hypoxia, or hypoxia of very rapid onset, changes
in levels of consciousness, seizures, coma, priapism, and death occur. Severe
hypoxia induces a blue discoloration of the skin, called cyanosis. Because
hemoglobin is a darker red when it is not bound to oxygen (deoxyhemoglobin), as
opposed to the rich red color that it has when bound to oxygen (oxyhemoglobin),
when seen through the skin it has an increased tendency to reflect blue light back
to the eye. In cases where the oxygen is displaced by another molecule, such as
carbon monoxide, the skin may appear 'cherry red' instead of cyanotic
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Structure-logical scheme 2
MECHANISMS OF RESPIRATORY HYPOXIA
Disorders of
regulation of the
external respiration
Disorders of the
osteomuscular
apparatus of the
thoracic cage
Inflammatory,
dystrophic and tumour
processes in the lungs
Chang
function
alveolarmemb
RESPIRATORY HYPOXIA
Disorders of
blood
oxygenation
↓ tension of
oxygen in the
tissues
↓ supply of
oxygen to the
tissues
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↓ shares of oxide
phosphorylation
in the metabolism
of cells
Structure-logical scheme 9
PRINCIPLES OF HYPOXIA TREATMENT
Oxygen therapy
with normal partial pressure of oxygen
in the gas mixture or oxygen-barotherapy
Administration of antihypoxic agents
that produce beneficial effects on the processes
of biological oxidation in the tissues
Administration of antihypoxic agents which inhibit
the processes of free-radical oxidation of the
membraneous lipids
Symptomatic therapy –
administration of pharmacological agents whose action is directed at the
recovery of impaired functions of physiological systems of the organism
(cardio-vascular, hematologic, respiratory, CNS etc.)
Transfusion of blood or mass of erythrocytes
in order to increase oxygen volume in the blood
in hemic type of hypoxia
Antidote therapy
in poisoning with cyanides and nitrates
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VI. MATERIAL FOR SELF-CONTROL
Situation tasks:
1. Alpinists slowly climbed the mountain slope. Behind them were 6 hours of
climbing. Because of general weakness every stem required a lot of efforts.
Breathing became very difficult, heart beating became intensive and reached 140
beats per min. Dizziness, head aches, depression, decrease of appetite, meteorism.
1.What is direct cause of these disarrangements in the alpinists?
2.What is the name of this syndrome?
3.What is the mechanism of accelerating the heart beating and breathing?
2. With the help of external cooling hypothermia of various rates was caused at
two experimental animals. In one animal decrease of temperature was 10 Co, and
in other the external cooling did not caused hypothermia yet (compensatory stage
of hypothermia).
1.Elucidate how the sensibility to oxygen starving will change in these animals in
these terms?
3. With the help of different methods the state of hypoxia was caused at two
experimental rabbits: at one rabbit – with help of altitude chamber, at the other –
with the help of experimental causing of lung swelling.
1.Which adaptive reactions are working at the rabbits?
2.What is the difference between them?
4. Coming from the pathogenesis of hypoxia, propose ways of artificial improving
of resistance of the organism to hypoxia, name the most perspective ways of
specific antihypoxic means.
5. The group of patients from sanatorium went to the mountains for excursion.
Tachycardia and breathlessness developed in part of them in two hours after
beginning of excursion.
1.Which type of hypoxia do those disturbances result from?
2.What is the mechanism developmenthypoxya
6. A driver slept in garage in a car with working engine. When he woke he had
headache and later vomiting began in him.
1.What compound formation in blood caused this state?
2.Which type of hypoxia do those disturbances result from?
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Tests:
1. A man constantly lives in mountains. What changes of blood test indices can
found in him?
A. Increased red blood cells number
B. Decreased reticulocytes count
C. Decreased color index
D. Appearance of erythroblasts in blood
E. Decreased hemoglobin content
2. After autopsy a forensic medical expert established that death of 20-year-old
woman resulted from cyanide poisoning. What process disorder caused the death?
A. Tissue respiration
B Oxygen transport by hemoglobin
C. Hemoglobin synthesis
D. Urea synthesis
E. Oxidative phosphorilation
3. Increased number of erythrocytes in blood test was revealed in people residing
in village, which is situated in mountains at the altitude of 3000 m. What is the
reason for changes in their blood?
A. Increased erythropoietin production
B. Blood clotting
C. Change of spleen function
D. Increased vitamin B12 synthesis
E. Increased circulating blood volume
4. Which sportsman will have highest content of lactic acid in the blood?
A.. Who just had run 5000 m
B. Who just had run 100 m
C. Weight-lifter
D. Who put the shot
E. Jumper with pole
5. A 40-years-old man took cyanic potassium by mistake. He died instantly. What
mitochondrial enzymes do cyanides block?
A. NAD-dependent Dehydrogenases
B Cytochrome Oxydase
C. Cytochrome B
D. Cytochrome C
E. FAD-dependent enzymes
6. Pain in muscles appears after physical exertion in people, who move a little
(have hypodynamia) for a long time. What is the possible reason for this?
A. Accumulation of lactic acid in muscles
B. Increased content of ATP in muscles
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C. Accumulation of creatinin in muscles
D Decreased content of lipids in muscles
E. Enhanced decay of muscle proteins
7. The number of erythrocytes in alpinist’s blood before going to mountains is
4,5x1012/L. What changes of erythrocytes number can develop at the altitude of
2500 m above sea level?
A. Absolute erythrocytosis
B. Absolute erythropenia
C. Relative erythropenia
D. Relative erythrocytosis
E. There won’t be any changes
8. Dyspnea, increased heart beat rate, weaken of attention, foolishness occurred in
sportsmen without acclimatization during the ascent to the altitude of 3000 m.
Then weakness and disturbance of muscular coordination occurred. What was the
reason for that condition?
A. Hypoxic hypoxia
B. Circulatory hypoxia
C. Respiratory hypoxia
D. Hemic hypoxia
E. Hypercapnia
9. Total respiratory insufficiency was noticed on examination of blood gases
partial pressure in a patient with bronchial asthma. What is the reason of
respiratory hypoxia in this case?
A. Decreased ventilation
B. Decreased diffusion
C. Increased ventilation
D. . Increased perfusion
E. Increased diffusion
10. Total respiratory insufficiency developed in a patient with lung disease. It
manifested by decreased pO2 and increased pCO2 in patient’s blood. What caused
development of respiratory hypoxia and pronounced respiratory insufficiency?
A. Frequent shallow respiration
B. Excessive hyperventilation
C. Oxygen deficit in inspired air
D. Uneven ventilation of the lungs
E. Functional blood shunting in the lungs
11. Disorders of oxyhemoglobin formation have led to development of hemic
hypoxia. What are the reasons for hemic hypoxia development?
A. Methemoglobin formation
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B. Inhibition of dehydrogenases
C. Pronounced polycytemia
D. Activation of Glutation Peroxidase
E. Deficiency of riboflavinum
12. Which factors increase hypoxic injury of a cell under hypoxic conditions?
A. Catecholamines
B. Inhibitors of proteolysis
C. Glucocorticoids
D Chinon derivations
E. Glutation-peroxidase
13. Symptoms of poisoning such as sharp weakness, dizziness, headache,
vomiting, dyspnea, tachycardia, cyanosis of lips, ears, distal phalanges of fingers
occurred in one child from group of children, who had eaten sweet juicy
watermelon. Laboratory test of watermelon showed high level of nitrates. What is
leading mechanism in pathogenesis of only one child poisoning?
A. Methemoglobin reductase deficiency
B. Cytochrome oxidase blockade
C. Glutathione peroxidase deficiency
D. Superoxide dismutase deficiency
E. Catalase deficiency
14. A man has been living high in mountains for a long time. What changes in his
blood would develop?
A. Increase in quantity of hemoglobin
B. Increase in diameter of blood vessels
C. Decrease in number of leukocytes
D. Increase in number of leukocytes
E. Rare pulse
15. Tachypnea and hypopnoe developed in tourists, which had climbed to the
altitude of 3000 m. These changes are consequence of stimulation of
A. Chemoreceptors of carotid sinus
B. Mechanoreceptors of pulmonary alveoli
C. Baroreceptors of arch of aorta
D. Neurons of the cerebral cortex
E. Motoneurons of spinal cord
All correct ansvers - A
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REFERENCE
Educational:
1) Pathological physiology. After redaction of A.I. Bereznyakova. Charkiv: Zoloti
storinky. 2003
2) Pathological physiology. After redaction of M.N. Zayka, Yu.V.Byts. Kyiv:
Vyshcha shkola, 1995.
3) Pathological physiology. After redaction of A.D. Ado, V.V. Novytsky, Tomsk:
Un-ta. 1994
4) Pathological physiology. The course of lectures. After redaction of P.F.
Letvitsky, M.:Medicina.1995
5) Agadganyan N.A. Organism and gas environment. M., 1972
6) Big medical encyclopedia.
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