INTRODUCTION TO 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 Life Logic Healthy 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 dynamics of pathological processes, with temporal and spatial characteristic, and with changes of intensity in 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, their role 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, and 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 Final definition 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 International 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 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 Relation among pathophysiology and other subjects of unergraduate medical education Sciences 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, medical ethics, sociology, antropology, phylosophy, demography...) – psychologic and social factors play an important role in pathogenesis of diseases Learning outcomes 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 Medical students construct their own virtual house of medicine „House of Medicine“ Neurology Gynekology and Obtetrics Surgery Internal medicine Ceiling plate PATHOPHYSIOLOGY Pathology Pharmacology walls Microbiology PHYSIOLOGY Base plate Anat Biol Histol Bioch Foundations Chem Biophys Structure of pathophysiology 1. General pathophysiology 2. Special /organs, systems/ pathophysiology General pathophysiology 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.... General pathophysiology also deals with ● 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 pathophysiological (clinical)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, and with symptoms and signs characteristic for dieing process 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 – e.g.: • 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 NOTES 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 also 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) In positive feedback a change in the homeostatic condition is detected by receptors and the information is transmitted to the control centre. The control centre activates effectors which generate a response which increases the stimulus further reinforcing the initial change. Therefore, positive feedback acts to reinforce or strengthen the stimulus or charge. 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 systemic venes formation of edema COLV fluid volume activation sympathic vasoconstriction in venous system 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 16th century) HISTORY OF PATHOPHYSIOLOGY • C. Bernard (1813-1878)-Introduction to experimental medicine(1865) • Rudolf Wirchov (1821-1902)-the father of modern pathology, he introduces also term „pathological physiology“ to medical terminology • Galliot (1819)-author of„Manual in general pathology and pathological physiology“ • A.F. Hecker (1763-1811) -author„Textbook in pathophysiology“ (1790) Excellent pathophysiologist from the past: J.E. Purkyne, Prof. Pashutin, Prof. Pavlov /from Russia/, Prof. Hans Selye /Canada1907-1982/ -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 Students should understand fundamental general and specific pathomechanisms involved in onset, development and ending of diseases For reaching this aims is necessary: a) to know and understand pathophysiological terms b) to know and understand essential pathomechanisms c) to connect separate factual knowledge and pathomechanisms to rational pathogenetic network characteristic for different pathological processes and diseses 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 best way how to obtain lasting knowledge is understanding of the pathomechanisms (Understunding is a kind of ecstasy) Textbooks and other sorces for study of PaPhy ● Silbernagel S, Lang F. Color Atlas of Pathophysiology Thieme, Stuttgart - New York, 2nd Edition 2010, 433pp. ISBN: 978-3-13-116552-7 ● McPhee SJ, Hammer GD. Pathophysiology of Disease – An Introduction to Clinical Medicine, Sixth Edition,2010, McGraw Hill Medical, New York-Toronto, 736pp. ISBN: 978-0-07-162167-0 ● Handouts of lectures on Pathophysiology – from Dept of Pathophysiology, JFM CU in Martin (yearly updated) ● Tatar M, Hanacek J. Pathophysiology. Topics for seminars. Comenius University 2001, 220pp. Huether SE, McCance KL. Understanding Pathophysiology, Fifth Edition, Elsevier Mosby 2012, 1159pp. ISBN:978-0-323-07891-7 Staff involved in teaching process Head of Department: Professor M. Tatar, M.D., Ph.D. Teaching staff: Teachers: Prof. J. Hanacek, M.D., Ph.D. - Vice-Head Prof. M. Tatar, M.D., Ph.D. Assoc. Prof. M. Brozmanova, RNDr., Ph.D. Assoc. Prof. R. Pecova, M.D., 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: J. Halicka, MD, Ms. S. Gavliakova, Ing. Secretary: Mrs. M. Ilovska