Introduction to Study of Pathophysiology

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INTRODUCTION TO STUDY

OF PATHOPHYSIOLOGY

Prof. J. Hanacek, M.D., Ph.D.,

What the pathophysiology is

• Physiologia, ae, f.

gr. fysis = nature; logos = science

• Pathophysiologia, ae, f.

gr. pathos = disease, pain, suffering

Physiology Pathophysiology

Healthy

Life

Logic

Study

Diseased

The calligraphy done by the Korean artis Kim Hyun-Seung

Pathophysiology - definitions

/PaPhy/

 PaPhy is a biomedical science on the mechanisms related to development and elimination of pathological processes and diseases

 PaPhy is a biomedical science dealing with functional changes in diseased organism

 PaPhy deals with the dynamic aspects of pathological processes and diseases. It studies disordered or altered functions - the physiologic mechanisms altered by disease in the living organism

Pathophysiology deals with temporal and spatial dynamics in the intensity of pathological processes

Pathophysiology is devoted to study of protective and defensive mechanisms of body tissue, organs and systems, and their role in defence against noxae, in pathogenesis of disease, and in sanogenesis

Pathophysiology belongs to core subjects of undergraduate medical education

Pathophysiology deals with logic of life under pathological conditions

Pathophysiology help us to understand the logic of life during development of pathological processes

Pathophysiology creates a bridge between sciences and clinical subjects in undergraduate medical education

 Pathophysiology is a modern integrative biomedical science founded on basic and clinical research that is concerned with the mechanisms responsible for the initiation, development, and treatment of pathological processes in humans and animals.

I nternational Society for Pathophysiology (1998)

• Why pathophysiology is important for medical students and physicians

1. It helps them to find answers to important questions related to disease processes: a) What is the cause/causes of the disease, and why the disease is developing b) What are the mechanisms responsible for disease onset, progression, and recovery c) What are the mechanisms responsible for development of symptoms and signs of disease

2. If doctors are able to understand the causes and mechanisms of the disease, then they are able to find the way how to influence them rationally

Relation among pathophysiology and other subjects of unergraduate medical education

Biology – pathological processes begin frequently at the cell level

Anatomy and histology – macro- and microstructural properties of the human body is essential for understanding their pathology

Biochemistry – biochemical processes are changed under pathological condition

Biophysics – biophysical properties of cells, tissues and organs determine their structural and functional characteristics

Physiology – firstly, we have to understand the functions of the healthy tissues, organs and systems of the body, than we are able to distinguish pathological functions

Pathological anatomy – to understand the microstructural and macrostructural changes under pathological conditions helps to understand functional changes and vice versa

Microbiology and immunology – the subject help us to understand of the mechanisms involved in development of disease caused mainly by biologic noxas and disorders of immune system

Pharmacology – PaPhy enables the doctor to treat diseases rationally (causally)

Clinical subjects – PaPhy is a theory of disease, clinic is medical practice

Humanistic subjects (psychology, ethics, sociology, antropology...)

– psychologic and social factors play an important role in disease development

The position of Pathophysiology in undergraduate medical education

• It becomes an integrative biomedical subject

• It becomes a bridge between the subjects of sciences and clinical medicine

• It is an important part of undergraduate medical education

THE MAIN TASKS OF PATHOPHYSIOLOGY

• To teach mechanisms of diseases

• To help to understand the substance of health

● To help students to understand the logic of life under pathological conditions

Thanks to pathophysiology the medical student can understand the inner logic of the pathological processes, their relationships, and their biological significance.

On this basis student is able, as a result, to built an individual model of disease in a given patient

„House of Medicine“

Neurology

Gynekology and Obtetrics

Surgery

Internal medicine

P A T H O P H Y S I O L O G Y

Ceiling plate

Pathology Pharmacology Microbiology walls

P H Y S I O L O G Y

Base plate

Anat Biol Histol Bioch Chem Biophys

Foundations

Structure of pathophysiology

1. General pathophysiology

2. Special /organs, systems/ pathophysiology

1. General pathophysiology – content

It deals with general pathologic processes , and pathomechanisms: thay are involved in pathogenesis of more than one disease. It also contain explanation of some basic medical terms

● Examples of general pathological processes – inflammation, fever, hyperthermia, hypothermia, shock, stress, edemas, disturbances of control mechanisms, hyperreactivity, hyporeactivity, damage of genetic information....

● Defensive and adaptive mechanisms –

- non-specific and specific immunity, hypertrophy, atrophy, hyperfunction, hypofunction, homeostasis

● Incresed predisposition to onset of disease

(diathesis, athopy) – due to genetic or/and environmental factors

Essential terminology

a) Nosology /nosos = disease; logos = science/

Systematically describes the specific type of disease and this is the base for creation classification system of diseases b) Etiology of disease /aitiá = cause/

Deals with noxae (causes) which are involved in disease onset and with conditions under which the causes are able to induce disease processes

( Oposit - etiology of health: deals with factors which promote the health)

c) Pathogenesis /pathos = pain, suffering, distress, genesis - onset/

Deals with mechanisms involved in disease onset and diseases development ( pathomechanisms )

d) Sanogenesis /sanos = health/

Deals with mechanisms involved in recovery from disease to health

e) Semiology /sémeion = sign, symptom/

Deals with symptoms and signs of diseases

Symptoms – subjective feeling of disease

Signs – objective parameters of changed functions and structures of body systems

f) Tanatogenesis /thanatos = death/

Deals with processes leading to death

2. Special pathophysiology - is devoted to analysis and explanation of pathomechanisms involved in functional disturbances of the organs and systems of the organism:

Content of special pathophysiology:

• hematologic disorders

• disorders of cardiovascular system

• dysfunctions of respiratory system

• disorders of uropoietic system

• neurologic disorders

• dysfunctions of of endocrine system

• metabolic disorders

• disorders of reproductive system

• dysfunctions of of GIT

SPECIAL SECTIONS OF PATHOPHYSIOLOGY

Clinical pathophysiology

/clinical physiology/

Space pathophysiology

Experimental pathophysiology

Pathophysiology of extreme - events

Ocupational pathophysiology and PaPhy of sports

Adaptation pathophysiology

● Cellular and molecular pathophysiology

REMARKS TO PATHOGENESIS

● Pathogenesis of disease processes can not be reduced to only quantitative changes of structures, functions and mechanisms presenting in healthy people

● It is necessary to take into account development of qualitatively new processes, which are harmful for the body structure and functions

One example of such new pathologic mechanism is vicious circle

(a complex of events that reinforces itself through a feedback loop toward greater instability)

Examples of vicious circle

1st example: Development of LV insufficiency

Mitral stenosis decreased cardiac output of left ventricle activation of sympathetic n.s.

 arter resist vasoconstriction

(skin, splanchnic, kydney aa.) heart rate end – diastolic vol of LV shorter diastola of LV

2nd example: Development of edema during RV failure

Right ventricle failure volume overload hydrostatic pressure in venous system formation of edema

COLV activation sympathic

 fluid volume in venous system vasoconstriction blood flow in kydney resorbtion Na + activation of in kydney R - A- A system

HISTORY OF PATHOPHYSIOLOGY

Hippocrates (460-370 BC)- he was the first to construct theories of the causes of disease based on what he had observed in his patients

His fundamental truth: „there are two factors acting alone or in combination which cause illness – the intrinsic or constitutional make-up of the person, and an extrinsic or environmental agent “, is still valid.

 Once normal functions of the body had been described it was but a step to investigate states of disease (from the end of 16 th century)

HISTORY OF PATHOPHYSIOLOGY

C. Bernard (1813-1878)-Introduction to experimental medicine (1865)

Rudolf Wirchov - he introduces term „pathological physiology“ to medical terminology

Galliot /1819 / - author of„Manual in general pathology and pathological physiology“

A.F. Hecker / 1790/ -author„Textbook in pathophysiology

Excellent pathophysiologist from the past: J.E. Purkyne,

Prof. Pashutin, Prof. Pavlov /from Russia/, Prof. Hans

Selye /Canada-1907-1982/ -Stress theory; ...

Methods used in pathophysiological research

1. Observation

2. Animal experiment

3. Clinical – pathopysiological study

4. Elaboration of experimental to create models of pathological processes – animal's models, mathemathical models...

Research at the Dept. of Pathophysiology

It is devoted to research on PaPhy of respiratory system, especially to defensive mechanisms of the airways and lungs, and to visceral neurophysiology and PaPhy

The main aims of teaching pathohysiology

1. Students should understand fundamental general and specific pathomechanisms involved in onset, development and ending of diseases

To fulfil this aim is necessary: a) to know and understand pathophysiological terms b) to know and understand essential pathomechanisms c) to connect separate pathomechanizms to rational pathogenetic network characteristic for different pathological processes d) to understand a pathologic process as event which influence the whole body e) to understand pathomechanizms as dynamic events

The roles of studets and teachers in teaching prosess a) Student has to study, not simply memorise facts b) Individual study and seminars should be focused to obtain lasting knowledge on pathophysiology c) Teacher will help students with creation of complex view on pathogenesis of diseases

• The source of lasting knowledge is understanding of the pathomechanisms

(Understunding is a kind of ecstasy)

Textbooks and other sorces for study of PaPhy

● Sylvia Anderson Price, Lorraine Mc Carty Wilson,

Pathophysiology - Clinical concepts of disease processes

6th edition

Mosby Year Book, St.Luis, Baltimore, Boston, Chicago,

London, Sydny .

●Stefan Silbernagel, Florian Lang:

Color Atlas of Pathophysiology

Thieme, Stuttgart - New York, 2000, 406pp.

●S.J. McPhee, V.R. Lingappa, W.F. Ganong, J.D.Lang:

Pathophysiology of Disease An Introduction to Clinical

Medicine Prentice - Hall International Inc., 1995, 521pp.

● Tatar M, Hanacek J. Pathophysiology. Topics for seminars.

Comenius University 2001, 220pp.

● Handouts of lectures on Pathophysiology – from

Dept . of Pathophysiology JFM CU in Martin

Staff involved in teaching process

Head:

Professor M. Tatar, M.D., Ph.D.

Teaching staff:

Teachers: Prof. Jan Hanacek, M.D., Ph.D. - Vice-Head

Prof. Milos Tatar, M.D., Ph.D.

Assoc. Prof. R. Pecova, M.D., Ph.D.

Assoc. Prof. M. Brozmanova, RNDr., Ph.D.

Assoc. Prof. J. Plevkova, M.D., Ph.D.

Technicians: Mr. M. Vrabec,Ing., Ms. L. Mazurova, Mrs. K. Strbova

Mr. T. Zatko

PhD student: Mr. J. Halicka, M.D., Ms. S. Gavliakova, Ing.

Secretary: Mrs. M. Ilovska

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