General teaching about disease

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 REWORKS – every Monday at 4 p.m. (till last student)

Terminology
 Pathology – focus on physical changes in diseased
organs and tissues
 Pathophysiology – abnormal functioning of
diseased organs and how it applies to medical
treatment and patient care

Pathological physiology is the science, which studies the
general law fullness of disease genesis, development and
the end.
This is the science about the vital activity of sick organism.
Pathological physiology is the study of the most common
options of the disease genesis and development, while
clinical sciences study specific items of disease prevention,
diagnostics and treatment.

Pathological physiology, as a science, solves the following
problems:
 illness essence establishment;
 disease causes and it’s beginning conditions study;
 illness development, display, course and the convalescence
mechanisms separate explanation;
 diseases prevention and cure general principles
determination.

The pathological physiology is related to the other
sciences. The following connections are:
a) to the sciences, which study illness causing environmental factors
(physics, chemistry, biology, microbiology, the social sciences), they
are necessary for etiology studying;
b) to the sciences, which study the organism properties and its vital
functions (cytology, embryology, histology, the normal physiology,
biochemistry, immunology, genetics), they create a base for
pathogenesis study;
c) to general theoretic sciences, which study an the disease (pathological
anatomy, pharmacology), in common with pathological physiology
create a total picture of the illness;
d) to the clinical sciences, helping to
determine the basic etiological and
pathogenic principles of disease
prevent, diagnostics and cure.
The clinic arises the problems and
gives the necessary material for their
solvation to pathophysiologists.

The connect between the pathophysiology
and other disciplines

Methods of
Pathophysiolog y
1. Clinical
2. Epidemiological
3. Anatomic
4. Experimental
 The peculiarity of pathophysiological
experiment is the reproducing of the
experimental disease models upon
laboratory animals with the purpose to
establish the mechanisms of their genesis,
development and in human organism.

• The experimental disease model is the artificial reproducing of disease up
the laboratory animals, which has the same lines of the proper human
disease.
• Though an experiment up animals does not give us the full picture of the
proper human disease, it enables to observe and to study the disease
course the beginning to its completion, that is impossible in clinics. During
the experiment one can control the environmental conditions, which
influence upon the illness course and have the objective material for the
scientific theories construction.
• The experiment can be divided into the acute and the chronic one.
• The acute experiment is based on the surgical intervention in animal
organism. It examines the acute disorders in organism (shock, collapse,
sharp breathing insufficiency, blood circulation insufficiency, etc).
• The chronic experiment is a protracted one, shows the illness
development dynamics. It is used for chronic diseases modeling (diabetes,
atherosclerosis, arterial hypertension, ulcerous disease etc).

 Pathological physiology consists of such parts:
► the general pathology and
► the pathophysiology of the organs and systems.
 The general pathology unites such parts:
► nosology,
► pathogenic environmental factors action,
► inner factors role in pathology,
► typical pathological processes,
► the typical metabolic disturbances.
 The pathophysiology of organs and systems
studies the general development of pathological
processes in separate functional systems; the most
widespread nosological forms are etiology and
pathogenesis .

The general nosology
includes such notions:
health
disease
pathological process
pathological state
pathological reactions

Nosology
► Nosology (fr. Gk nosos, disease + logos, science) is a general
science of diseases including the basic concepts and categories of
pathology, classification and nomenclature of diseases, social aspects
of pathology.
► Nosology deals with many problems: building basic scientific terms,
used in medicine: Health and Disease, pathological processes,
conditions, pathological reactions, stages of a disease, its
complications, and other terms which are of medical importance.
► Development of nomenclature of diseases and their conditions.
► Building a classification of diseases.
► Laying the foundations for the general study of diseases.
► Developing a theoretical conception of medicine.
► Basic concepts of nosology:
► Health, disease, normal, pathological reaction, pathological process
and pathological conditions.

TERMINOLOGY
• Etiology (fr. Gk aetia, reason + logos, science) is the science of
causes and conditions of disease occurrence. Etiology studies
general properties of pathogenic factors, basic categories of
pathogenic factors, significance of conditions in occurrence of
diseases, principles of etiotropic prophylaxis and etiotropic
therapy.
• Pathogenesis (fr. Gk pathos, disease + genesis, origin) is the
science of mechanisms of development, course and outcome of
diseases. The science of pathogenesis includes: mechanisms of
stability of organism to the action of pathogenic factors, general
mechanisms of development of diseases, mechanisms of
recovery, mechanisms of dying, principles of pathogenetic
prophylaxis and pathogenetic therapy.
• Biological modeling is an artificial reproduction of disease
processes in a living organism (in a cell, organ, entire organism).

TERMINOLOGY
• A pathological reaction (fr. Gk pathos, affliction, disease; Lat. re- -
against, actio - action) is an organism response to extraordinary irritant,
which is sometimes a symptom of disease.
• A pathological process is a complex of pathological and protective-
adaptative reactions as a response to a damaging effect of a
pathological factor.
• A typical pathological process is a pathological process developing in
accordance with the same rules, irrespective of reasons and localization.
• A pathological function (fr. Gk pathos, affliction, disease; Lat. functio,
activity) is a disorder of function of a cell, tissue, organ, system of organs
and vital activity of organism).
• A pathological reflex (fr. Gk pathos, affliction, disease; Lat. reflexus,
reflected) is a disorder of functional activity of organs, tissues or
systems, occurred with participation of CNS in response to pathogenic
irritation of receptors and manifested as pathological reactions of
organism.
• A pathological condition (status pathological) is a stable abnormality of
organism functions, a sluggish pathological process or the consequence
of an earlier suffered pathological process.

Health is the condition of complete
physical, psychic and social well-
doing, but not only diseases or the
physical defects absence (WHCO –
World Health Care Organization).
In doctor’s practical activity determination is used,
according to which health is the condition of a norm. There
is a question: what is the norm?
There are two approaches to this notion determination: the
statistic and the general physiologic one.
According to the first one, the norm is the condition, which
is the most frequently observed among people.
According to the second one, the norm is the biological
optimum of the organism functioning and development.
The second determination reflects the scientific approach
to the notion which is “a norm”. However this approach
remains still unrealized because of our knowledge and
possibilities limitation.

Disease – loss of
homeostasis, or when physical
or mental capacities cannot be
fully utilized (interuption,
cessation or disorder in the
function of an organ or
system).

 The disease is disturbance of human
organism vital activity under the influence of
extraordinary factors of external or inner
environment which is characterized by
lowering of capacity for work and adaptation
with simultaneous mobilization of protective
forces.

• Stages of a Disease.
1. The latent period or incubation period of an infectious disease.
The incubation period of a disease lasts from some hours to
some days or years. The patient must be isolated or
hospitalized.
2. Prodromal period of a disease. The patient develops
generalized clinical symptoms of a disease (complaints of a
headache, slight malaise, chills, rheumatic pains in his joints as
well as muscular pains). The doctor can make a preliminary
diagnosis in this period of disease development.
3. Dromal period of a disease. It is marked by all clinical
characteristics of a disease. In the dromal period the patient
develops all specific clinical symptoms. The doctor has to make
the final, basic diagnosis in this period of disease
development.
4. Outcome of a disease will be favorable or unfavorable.
– recovery - complete or incomplete
– recurrence
– chronic disease –remission and exacerbation
• Terminal state
• preagonal state
• agonal state
• clinical death
• biological death.

 The diseases endings are following: convalescence ( complete
and incomplete), recurrence, into chronic form transition, the death.
 The convalescence is the process, which conduces to the
violations liquidation, caused by an disease, and normal relations with
the environment restoration, for human beings – foremost the ability
to work restoration. The full convalescence is the state when all the
disease signs disappear and organism restores its adaptation
possibilities completely. When the convalescence is incomplete the
disease consequences are expressed. They remain for a long time or
forever. The convalescence is provided by the urgent (emergency)
and lasting protectively-compensational reactions of the organism.
 The remission is the temporal state improvement of the human
being, which is displayed by the disease progressing slowing down or
cessation, the partial reverse development or the disappearance of
the pathological process clinical signs.
 The recurrence is the new disease display after its seeming or
incomplete cessation.
 The complication is secondary as for reference to the disease
pathological process.
 The transition in the chronic form signifies that disease courses
slowly with the protracted remission periods (months and even
years). So, many diseases acquire chronic nature in old age (chronic
pneumonia, chronic colitis).

The terminal states are the boundary ones between life
and death. This is also the dying, which include a few stages:
pre-agony, agony, clinical death, biological death.
► The preagony is characterized by the diverse duration (during hours, days) of
deep violations of the vitally important organism functions. The dyspnea, the
decreasing of the arterial pressure, the darkening down of the consciousness,
which are observed in this period. Gradually the pre-agony gets across in the
agony.
► The agony is characterized by the gradual turning down of all organism
functions. The agony lasts 2-4 minutes, sometimes more.
► The clinical death is such condition when all of the visible sparks of life have
already disappeared (the breathing and the heart work are ceased, however the
metabolism still continues). The life can be restored on this stage.
► The biological death is characterized by the irreversible changes in the
organism.
► The reanimation of the organism includes number of measures which are
directed foremost to blood circulation and breathing renewal: heart massage,
artificial lungs ventilation, heart defibrillation. The indirect heart massage is
widely used for the renewal of blood circulation, it can be used at once after the
clinical death setting in any conditions and even not by specialist. The artificial
ventilation of the lungs also must be started as soon as possible. The heart
fibrillation is observed in the terminal period ordinary. In such cases the electric
defibrillation is used. A single digit to 6000 V removes the fibrillation and
promotes the renewal of the blood circulation.

Cause of a Disease
• One of the most important and difficult
questions is the problem of establishing the
cause of a disease. The tactics of the
physician and the success of treatment of
various diseases depend on the correct
solution of this problem. Pavlov believed
that a problem of etiology is the least
investigated problem of medicine. In the
course of development of natural history the
theory of etiology of diseases has been
changing. Each etiological theory was
influenced by the dominant ideas of the
time it was formed at. The old theory could
not account for new facts. There were two
ways of doing research: either to deny the
facts or to change theories interpreting
them.
• The ancient medicine gave rise to the idea
of a causative agent as a major etiological
factor. XVII –XVIII centuries witnessed the
development of a new doctrine known as
mechanical determinism.

Theories
•The mechanical determinism of XVII-XVIII
centuries was of great significance for the
development of the theory of pathology. Within a
framework of mechanical determinism some basic
methods of establishing causal connection (method
of isolation, method of similarity, method of
differences, method of attendant changes, method Louis Paster
of remainder) were elaborated. These methods are
still of great importance nowadays.
• The important stage in the development of this scientific
trend was elaboration of the theory of mechanical
monocausalism.
• The origin of this theory was prompted by discoveries of
infectious pathology. Within a short period of time the
causative agents of most widespread infectious diseases
were discovered which was inspired by Paster’s idea that
diseases may be caused by infectious agents. Many
scientists overestimated the importance of microbes in the
development of diseases.

Theories
• Monocausalism was most fully reflected in the conception of Genle -
Kock:
• A certain microbe causes a certain disease, it can be found neither in
healthy people nor in people suffering from other diseases.
• A microbe can be isolated in a pure culture.
• Pure microbial culture will cause the disease whose causative agent it is
supposed to be in experiment.
• This conception was of great importance as it channeled the research into
discovering numerous microbes.
• However, there was some clinical evidence which contradicted this
conception. Firstly, the study of severe epidemics revealed that not all
people get infected and develop a disease. Nor all of those infected die.
Secondly, there was experimental evidence that a hen which is not subject
to anthrax in ordinary conditions dies if its legs are kept in cold water for a
while. Thirdly, milkmaids that had had cowpox did not catch smallpox
during epidemics.
• Finally, in 1884 Lefler discovered the fact of carriage of bacilli. He found
virulent streptococci and pneumococci on the mucous membranes of the
pharynx and on the tonsils of healthy people.

Theories
Later a new theory of conditionalism gained popularity.
The founder of that theory was Ferworn. He formulated
five principles of this conception.

1. The first of them is as follows. There are no isolated and absolute
things. All processes or states are conditioned by other processes or
states.
2. There are no processes or states which are determined by a single
factor. All processes or states are conditioned by a large number of
factors (doctrine of multiple conditions).
3. Every process or state is unequivocally determined by the sum of their
conditions
4. Every process or state is identical to the sum of their conditions.
5. All conditions of any process or state are equally significant.
• Conditionalism is a subjective idealism theory. Microbes alone can not
account for the origin of infectious processes. But we should not
underestimate the role of microbes in this process.

Theories
• Another step in the development of the doctrine of
etiology is constitutionalism. The founders of this
theory believed that diseases may be caused by a
constitution type. These types are as follows: normal,
asthenic or hyperstenic constitution. Each type of
constitution has its own peculiarities. People of asthenic
constitution are subject to stomach ulcer and
tuberculosis. People of hyperstenic constitution are likely
to suffer from myocardial infarction or bronchial cancer.
This theory is based on the theses of formal genetics
and on genotype invariability. However, a genotype can
change under the influence of many exogenous and
endogenous factors. Therefore, this theory can not be
considered true.

Theories
The next theory was elaborated by Zigmund Freud.
This author distinguished three main systems in the
psychic (mental) structure of a person: the conscious,
the subconscious and the unconscious. The latter is the
home for sexual instincts.
• The conscious constantly suppresses these instincts. Freud believed that a
daughter’s love for her father, a son’s love for his mother are manifestations of
sexual instincts. Human consciousness constantly suppresses these sexual
instincts. But having a high power charge they tend to struggle their way to
consciousness. This results in the development of numerous diseases such as
schizoprenia, epilepsy, neurosis, etc.
• Zigmund Freud's conception had a great effect on the western medical science.
It also gave rise to a new branch of medicine, i.e. psychosomatic medicine. The
supporters of this branch of medical science suppose that diseases may be
caused by psychological conflicts in childhood. Different pathological processes
are conditioned by different stages of children’s development when disorders
occur.
• Under 6 months of age an infant seeks for his mother’s love and has a food
instinct. Disorders at this age lead to bronchial asthma or ulcer. Under 3 years of
age a child has an inclination for analysis. They often break their toys and other
things. If parents forbid to do this a child gets aggressive and spasms of the
muscular system occur. From 3 to 6 years a child develops a sense of self and
sexual feelings. Disturbances at that age will result in hysteria and in various
sexual disorders.

• Thus, we have outlined the main theories of etiology in medicine. Nowadays
etiology is a theory of causes and conditions of a disease development.
• A cause determines specificity and quality of the bodily reaction to a
pathological process. A cause also determines connections and regularities
of the processes. For example, tuberculosis is caused by Micobacterium
tuberculosisIt is responsible for specific and morphological changes typical
of it.
• The following these underlie the modern idea of causality:
• All natural phenomena have their own cause, there are no causeless
phenomena.
• The cause is material, it is independent of our existence.
• The cause interacts with the organism. Changing the body, the cause
changes itself.
• The cause gives a new quality to a process. It is the cause that makes a
pathological process special and unique.
• Classification of causes:
• Exogenous: physical, chemical, biological, psychic/mental and social.
• Endogenous.
• Conditions.
• Psychic/mental conditions in childhood.
• Urbanisation.
• Industrialisation.
• War.
• Unemployment.

The diseases classifications are
based on the following criterias:
• 1. The etiological classification is founded on the cause community for
the diseases group. For example, there are the infectious and uninfectious
diseases. According to the same principle one can group the diseases
caused by an intoxication (food, professional), genes violations and
chromosomal mutations (hereditary diseases) etc.
• 2. The topography-anatomic classification is based on the organ
principle: the cardiovasculars diseases, diseases kidneys, diseases of
nervous system etc. It is comfortable for practice. Besides, it corresponds to
the modern specialization of the medical help. It combines with the
classification of the functional systems: blood system, digestive system,
musculosceletal apparatus diseases etc.
• 3. The age and sex disease classification. There are the children’s
diseases, the senile age diseases. The female genitals diseases are studied
by the gynecology.
• 4. The ecological diseases classification proceeds from the human
dwelling conditions: the air temperature, the atmospheric pressure, the sun
illumination.
• 5. The classification according to the pathogens commonness: allergic
and inflammatory diseases, neoplasms, shock, hypoxia.

The general etiology
• The etiology is the learning of disease
beginning causes and conditions. The notions
of causality and determinism are base of
etiology.
• A causality reflects an objectively existent
phenomenas connection, when one
phenomenon (cause) inevitably causes
beginning of the other phenomenon (result)
by the definite conditions. Any disease just
like a phenomenon has its own cause. The
beginning and the development of the disease
are not by chance but subordinated to the
definite lawfullness.

Classification of etiological factors
 They are exogenous (external) and endogenous (internal).
The exogenous factors:
 a) physical – mechanical influence, radiation, high and low
temperature, electric current, overloading, zero-gravity and
others
 b) chemical – the inorganic and organic compound; c) biological
– viruses, rickettsias, bacterias, Protozoas, helmints, Arthropodes
 d) psychic – a word
 e) social – society development level, traditions and others
The endogenous factors:
 heredity
 constitution
 age
 sex
 organism reactivity

Categories of etiology
Genetic disease– genes are responsible for a structural
or functional defect
Congenital disease– genetic information is intact, but
the intrauterine environment interferes with normal
development
Acquired disease – disease is caused by factors
encountered after birth (biological agents, physical
forces, and chemical agents)
Clinical manifestations – indications that the person is
sick
Symptoms – unobservable effects of a disease reported
by the patient
Signs – observable or measurable traits
Syndrome - a characteristic combination of signs and
symptoms associated with a particular disease.

Pathogenesis - sequence of events in the of development of a disease
Sequelae – lesions or impairments resulting from a disease
Acute conditions – rapid onset, develop quickly, usually of short
duration
Chronic conditions – longer duration onset may be sudden or
insidious
Distribution of lesions may be:
Local – confined to one area of the body
Systemic – widely distributed throughout the body
Within an organ damage can be:
Focal if there are only one or more distinct sites of damage
Diffuse if the damage is uniformly distributed
Diagnosis – identification of the specific disease
Therapy – the treatment of the disease to either effect a cure or
reduce the patient’s signs and symptoms
Prognosis – prediction of a disease’s outcome

Risk Factors
The risk factors are the factors
combinations, the presence of which in
people population statistically increases
morbidity by definite diseases. The
belonging of these or those conditions to
the risk factors is determined
by epidemiological methods, which envelop
the large people contingent.
So it was established, that the violation of
blood plasma lipid composition, arterial
hypertension, the age, belonging to male,
obesity, hypodynamia, hereditary factors,
stress are the atherosclerosis risk factors.

Adaptation and compensation
 The base of adaptation and compensation are the
same mechanisms which are named protective
-adaptation or protective-compensatory. The distinction
between these notions: is adaptation develops in
augmentation of the action intensity of usual factors
environmental. The damage hasn’t happed yet, and the
homeostasis indexes are coming to the extreme norm
borders. The compensation develops in the action of
the pathogenic factors when a damage takes place and
the homeostasis indexes are beyond the extreme
borders norms.

Adaptation and compensation in disease
development
 1. The stage of immediate adaptation and compensation. The
mobilization of existing mechanisms and reserves begins and as a
result of loading on functioning system unit increases, its
hyperfunction develops. On this stage the events develop according
to such scheme: the action of pathogenic factors → the violation of
homeostasis → the perception of homeostasis violation → regulatory
centers → immediate protective reactions (specific and unspecific)
→ the hyperfunction of proper structures, supporting homeostasis.
 2. The stage of the long duration adaptation and compensation. The
augmentation of systems power, responsible for adaptation and
compensation is its base. It is reached by the augmentation of the
structures amount, providing a hyperfunction, so hypertrophy
develops. The hyperfunction → violation of intracellular homeostasis
→ activation of genomes → decrease of the proteins synthesis →
cell hypertrophy.

The general pathogenesis
• The pathogenesis is the study about the mechanisms of the
development, the course and the end of disease. The pathogens
studies everything taking place after the cause action.
• It is necessary to mention the following questions in disease pathogenesis
consideration:
1) the role of etiological factor in disease development;
2) the organism reactivity significance for the disease beginning and the course;
3) the significance of the general and local changes and their correlation;
4) the basic link of pathogens and causally-investigation intercourses;
5) the significance of functional and morphological changes and their correlation in
disease;
6) the significance of nervous system functional changes for disease development.
There are three variants of connections between a
cause and a pathogens:
1) Etiological factor initiates the pathologic process and then disappears, so the
pathogenesis develops without etiological factor (trauma, radiation).
2) The cause continues its action throughout all the period of the development of
the disease (infectious disease), as consequence the etiological factor
penetrates into pathogenesis, exist in it and influence it.
3) Persistence of the cause agent, which causes the disease, is delayed in
organism (healthy bacilli-carrier).

How does pathogenesis divide?
(four periods of pathogenesis)
• The pathogenesis is a new complicated process in the
organism with the two quite opposite processes:
• 1) "the measure against the disease" (by I.Pavlov) — it
means the compensatory and protective reactions
• 2) "pathologic process proper"
• So, the pathogenesis is a unity of opposites, which always
fight (law of dialectics). The doctor must find out pathologic
process the proper and stimulate the protection. There are
four stages of pathogenesis:
• 1) latent period (incubation period of the infectious
diseases); 2) prodromal one; 3) the period of expressed
manifestations; 4) the outcome of the disease.

Local and Systemic in Pathogenesis

• The study of pathogenesis of diseases proved that hare
are neither purely local nor purely systemic diseases.
The effectiveness of treatment depends on the correct
understanding of this idea.
• All diseases are local and systemic at the same time,
which determines the development of processes. Dental
caries can be treated using a stopper. If caries results
from a systemic disorder of mineral and albumin
exchange it requires a general treatment.
• The correlation between local and systemic changes
must be timely considered.
• A local process, for example, a furuncle can develop as
a result of the impairment of defense mechanisms of the
organism which limits this process and makes it local.

Local and Systemic in Pathogenesis

Causally-investigation
Relations
 The changes in organism which arise during disease development are in definite
causally-investigation relations, it means that the same phenomenon of
pathogens is the result of violations and cause of other. Such type of causally-
investigation relations when the definite links the pathogens over violation
sequence bring to their heightening over so called “the vicious round ”. It
supports itself the pathogens of the disease and redoubles its course. So, in
pathogens of any shock lowering of arterial pressure has big significance that
becomes cause of anoxaemia. The cerebral hypoxia brings to the oppression of
vasomotor centre and greater lowering of arterial pressure (a circle locked).
 The main link of pathogens is the process which is necessary for a development
of all the rest. The liquidation of the main link in time brings to removal of
pathological process as a whole. The main principle of pathogenetic diseases
cure is founded on it. So, in diabetes mellitus the insulin lack is the main link of
pathogens. Its liquidation (the introduction of hormone) brings to disappearance
of other displays (hyperglycemia, glucosuria, polydipsia, ketonemia, comas).
 In pathogens specific and unspecific processes and mechanisms are always
combined. The specific ones depend on the cause properties and determine the
basic disease descriptions. A search of the specific signs lays in base of
diseases recognition (diagnostics).

Vicious circle
Causes and consequences
constantly change their
places. The cause
(etiological factor) causes
the pathologic reactions
(process) and than these
reactions return to the first
agent (etiological factor)
and intensify it. So "vicious
circle" is formed m
pathogenesis For example,
if arterial pressure decrease
it causes the hypoxia and
than vasomotor center
depresses. It leads to the
prolonged decrease of
arterial pressure.

Nonspecific and Specific
Signs
 Every disease can have its signs that are typical of this
disease only (for example, irradiation of the pain in
angina pectoris), while other signs are typical of many
diseases or even for all. This common nonspecific
aspect of pathogenesis depends on the reactions of the
organism developing in the course of evolution and is
hereditary. There are five nonspecific reactions:
 Parabiosis. This is stable, non-spreading excitation,
which occurs in damaged excitable tissues. It is
important in pathogenesis of some forms of cardiac
blocade.
 Dominant reaction. This is a condition of a stable rise of
excitability of the group of nerve centers, which regulates
the overall activities of the body. The dominating
motivation gives rise to other dominants such as
nutritional, sexual, etc.

Negative effect of changes of atmospheric pressure
 A man feels the effect of decreased atmospheric pressure during ascent on plane or in mountains, or the
pilots flying in nonhermetically sealed cabin.
 The pathologic changes, occurring in it, are caused by two main factors:
 a) decrease of partial pressure of oxygen in inspired air;
 b) decrease of atmospheric pressure (decompression).
 The clinical signs of decompression syndrome are: pain in the ears and frontal sinuses because of expansion
of air in these cavities, nasal bleeding, because of bursts of small vessels. Bursting of alveoli and vessels
causes the gas bubbles to into the blood circulatory system (gas embolism, hypoxia, boiling of blood and
other liquids, especially at the height of 1900 m).
 A man feels the effect of increased atmospheric pressure in water during diver’s or caisson works.
 The most important is the fact if of quick increase of atmospheric pressure (hyperbaria) so the rupture of
lung alveoli occurs and additional quantity of gases dissolves in blood and tissues (saturation). Nitrogen plays
a key-role in breathing with the compressed air. The quantity of nitrogen in the body can sometimes increase,
especially in the organs, which contain a lot of lipids (nervous system).
 The first manifestation is a light excitement, like euphoria, the next are the phenomena of narcosis and
intoxication.
 Not only nitrogen is toxic, but also oxygen (hyperoxia) realizes its toxic effect a little later. The hemoglobin
molecule is blocked by oxygen and loses its ability to carry out carbon dioxide. The result is that
oxygemoglobin practically does not dissociate and carbon dioxide is not removed.
 Toxic effect of high concentration of oxygen is similar to the effect of radiation. In both cases the formation
of free radicals and peroxides with strong exudative abilities causes affection of DNA and tissue enzymes.
 The antioxidant therapy must be used, such as tocopherols, glutathione, ubiquinone and others, which
suppress free radical oxidation. Decompression can be used which is a method of returning of the man into
the conditions of normal atmospheric pressure and the excretion of the excess quantity of dissolved gases
via blood and lungs (desaturation).

Pathogenic influence of electric current

• Mechanism:
• Electric energy is transformed into:
• 1. Mechanical tearing off tissues and bones and even part of the body
• 2. Thermal – temperature in place of penetration may be 120 °C and
more – than burns arise
• 3. Chemical – electrolysis may cause changes of biological potential of
the different cells.

The effect of ionizing radiation
• The rays of high energy (X- and γ rays), α and β-particles, proton possesses
the ability to penetrate into the radiated environment and produce ionization.

The Effect of the Thermal Factors
1. The effect of the high temperature (when the air
temperature elevation varies from 33 °C to 37°C, it is
equal to the body temperature) is the development of
the overheating (local effect – burn), or the effect of
the low temperature – hypothermia.
2. Characterize overheating.
 There are two stages:

1) Compensation stage, when normal temperature is
preserved.
2) Decompensation stage, when overtension of
thermoregulation leads to its exhaustion.
3. Describe hypothermia.
 The effect of the low temperature on the body may
result in the decrease of the body temperature and the
development of pathological condition – hypothermia.
There are two stages of overcooling:
1. Compensation stage is directed at limitation of the
heat emission.
2. Decompensation stage or hypothermia proper.

Crush Syndrome
 Crush syndrome (CS) is a variant of
traumatic disease. The main pathogenic
factors in CS are:
1) Pain syndrome
2) Intoxication
3) Psychoemotional stress
4) Hypovolemia
 Characterize the clinical course of
crush syndrome.
 There are three periods in the clinical
course of crush syndrome:
1. Early (to 3 days, with compression and
decompression phases)
2. Intermediate (from 8 to 12 days) with the
prominence of acute renal insufficiency
(ARI)
3. Late (from 12 days to 1-2 months — the
period of recovery with the prevalence of
local syndromes.

Literature
 Basic:
1. General and clinical pathophysiology / Edited by Anatoliy V. Kubyshkin –
Vinnytsia: Nova Knuha Publishers – 2011.
2. Pathophysiology, N.K. Symeonova. Kyiv, AUS medicine Publishing, 2010.
3. Gozhenko A.I., Gurcalova I.P. General and clinical pathophysiology/ Study
guide for medical students and practitioners.-Odessa, 2003.
4. Essentials of Pathophysiology: Concepts of Altered Health States (Lippincott
Williams & Wilkins), Trade paperback / Carol Mattson Porth, Kathryn J.
Gaspard. – 2003.
 Additional:
5. Robbins basic pathology, 7/e / Kumar et al. – Indian reprint, 2004.
6. Pathological physiology / Yu.I. Bondarenko, M.R. Khara, V.V. Faifura, N. Ya.
Potikha. ‑ Ternopil: Ukrmedkniga, 2006.
7. Pathophysiology, Concepts of Altered Health States, Carol Mattson Porth,
Glenn Matfin.- New York, Milwaukee- 2009 p.
8. Stephen J. McPhee. Pathophysiology of Disease. An introduction to Clinical
Medicine / Stephen J. McPhee, William F. Ganong // Lunge Medical
Books/McGraw-Hill. – 5th edition. – 2006.
9. http://testcentr.org.ua/
10. http://kroktest.org.ua/kroki/krok-1/foreign-tests/examination-tests-or-booklets-
foreign-students-englishstep-1
11. http://online.kroktest.org.ua/

General teaching about disease

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