Introduction to Pathophysiology

1. Introduction to Pathophysiology Dr. Mohamad Nidal Khabaz Assistant Professor of Pathology, Pathology Department, Faculty of Medicine, Jordan University of Science and Technology

2. Learning Outcomes 1. Define and use the key terms listed in this lectures. 2. Recognize the value of knowledge gained in prerequisite science courses as a base for learning pathophysiology. 3. Compare and contrast the terms “health” and “illness” with the term “disease.” 4. Communicate effectively with others by using accurate pathophysiologic terminology. 5. Explain the conceptual approach to learning general health alterations and applying them to specific disease conditions.

3. Foundations of Pathophysiology • This foundation focuses on human cells and, ultimately, on human structure and function. • Structureis the formation of the parts in the body; that is, how the body is put together. • Functionis the action or workings of the various properties of the body. • What happens when structure or function is altered? • The study of pathophysiology focuses on that question and becomes the next step in the study of human health.

4. Definition of Pathophysiology • Pathophysiologyis the physiology of altered health states; specifically, the functional changes that accompany a particular injury, syndrome, or disease. This definition has two components. • First, it relies on the understanding of human physiology. A person must first understand how something works before grasping what occurs when something goes wrong. • Second, the core of pathophysiology is based on functional changes in the body. This relates to how the body responds to unexpected or undesired changes.

5. Related Sciences • Pathophysiology must be differentiated from other disease-related fields. • Pathologyis the study of the structural and functional changes in cells and tissues as a result of injury. • Pathophysiology is basically a combination of pathology and physiology; that is, structural and functional changes at a cellular and tissue level that impact the entire body. • Histologyis a branch of anatomy that deals with the minute structure of cells and tissues, which are visible with a microscope. • Pathophysiology builds on an understanding of the basic structure of cells and tissues.

6. Related Sciences • Morphologyis a branch of biology that deals with the form and structure. Morphology looks more specifically at how cells and tissues change in form after encountering disease. • Microbiologyis a section of biology dealing specifically with the study of microscopic forms of life. • All of these sciences and others are integrated into the study of pathophysiology

7. Sciences that support the understanding of pathophysiology.

8. Are you healthy or ill? • How do you know ? • What characteristics describe someone who is healthy ? • When does a person become labeled as ill ?

9. Health–Illness Continuum • This text is based on three major assumptions regarding health and illness: • The terms health and illness are on a continuum. This means that health and illness are not two exclusive categories. • The health–illness continuum is a dynamic entity (understanding of health and illness can change from day to day, or month to month). • Human health includes dimensions of not only physical, but also spiritual, emotional, and psychological well-being.

10. Health & Illness • Healthis the condition of being normal in body, mind, and spirit. Health can refer to life balance, (homeostasis). • Homeostasisis a dynamic steady state representing a constant balance that depends on communication between cells, body tissues, hormones, chemicals, and organ systems. • Illnessis a state that results in suffering or distress. Illness is often estimated by the presence of physical disease symptoms, (pain).

11. Disease • Diseaseis an impairment of cell, tissue, organ, or system functioning. Disease is a term often used synonymously with illness, sickness, or syndrome. • Disease is the result of altered body functions and poses a challenge to homeostasis. • The impact of disease can range from mildly irritating to totally debilitating. • The presence or absence of disease is often marked by specific signs and symptoms. • Disease can often be identified through various laboratory and diagnostic tests.

12. Remember that the overall goal in understanding altered body functions is to provide a high quality of care. Health care professionals care for the person and not the disease.

13. Using PathophysiologicTerminology to Communicate • Essential to the study of pathophysiology is the ability to use the appropriate pathophysiologic terminology. • The ability to effectively use this terminology can facilitate clear communication across the different health care disciplines. For example, (patient record).

14. Pathophysiologic Terminology • When considering an alteration in health, the pathogenesis describes how the disease starts, proceeds, and resolves. It explores factors relating to the human condition that allowed the disease to develop. • Questions that illustrate the pathogenesis include: • What risk factors were present to increase the chances that the disease may occur? • What precipitating factors, or triggers, led to the onset of disease? • What was the etiology, or cause, of the disease ? • What facilitated the disease progression? • What led to the resolution of the disease?

15. Examples of risk factors for coronary artery disease

16. Examples of precipitating factors for asthma

17. Using PathophysiologicTerminology to Communicate • The goal in studying the pathogenesis of illness is often to: • prevent diseases from occurring, • facilitate early diagnosis, • facilitate intervention to avoid complications. • The etiology focuses on the cause of the disease. • When a health condition does not have a clear etiology it is called idiopathic. • In many cases, the etiology of a health alteration is not well understood, or it is multifactorial.

18. Medical Terminology

19. Concepts of Medical Terminology • Special vocabulary used by health care professionals for effective and accurate communication • Based on Latin and Greek words • Consistent and uniform throughout the world

20. Word Parts • Root • Fundamental unit of each medical word • Establishes basic meaning of word • Part to which prefixes and suffixes are added

21. The Greek root nephr and the Latin root ren areused to refer to the kidney, an organ of the urinary system.

22. Word Parts (cont’d) • Suffix • Short word part or parts added to the end of a word • Modifies the meaning of the root • Indicated by a dash before the suffix (-itis) • Prefix • Short word part added before a root • Modifies the meaning of the root • Followed by a dash (pre-)

23. Word Parts (Examples) • Begin with “learn” • Learn + -er = one who learns • Re + learn = to learn again • Greek word for heart is kardia • Forms word root cardi • Latin word for lung is pulmo • Forms word root pulm

24. Combining Forms • Insert an ‘o’ before a suffix beginning with a consonant when added to a root [-logy = “study of”] [Neur = “nerve or nervous system”] • Neur + o + logy = neurology (study of the nervous system) • Roots shown with a combining vowel are called combining forms (Neur/o). • Combining vowel omitted if suffix begins with a vowel • Neur + it is = neuritis (inflammation of a nerve)

25. Words Ending in x • Change x to c or g when adding a suffix • Pharynx (throat) becomes pharyngeal (fa-RIN-je-al) (pertaining to the throat) • Thorax (chest) becomes thoracotomy (thor-a-KOT-o-me) (an incision into the chest)

26. Suffixes beginning with rh • Double the r in suffixes beginning with rh • Hem/o (blood) + -rhage (bursting forth) = hemorrhage (a bursting forth of blood) • Men/o (menses) + -rhea (flow, discharge) = menorrhea (menstrual flow)

27. Key Terms

28. Suffixes

29. Suffixes • Suffix = word ending that modifies a root • May indicate a noun or adjective • Often determines how word begins • Myel/o (bone marrow) + -oid = meyloid (like or pertaining to bone marrow) • Myel/o + -oma = myeloma (tumor of the bone marrow)

30. Suffixes That Mean “Condition Of”

31. Suffixes for Medical Specialties

32. Adjective Suffixes • Adjective endings meaning “pertaining to” or “resembling” include: • -ac as in cardiac • -form as in muciform • -ory as in respiratory • No rules for which ending to use with a given noun

33. Suffixes That Mean “Pertaining to or Resembling”

34. Prefixes

35. Prefixes • Prefix = short word part added before a word root to modify the meaning • Uni- (one) + lateral = unilateral (affecting or involving one side) • Contra- (against) + lateral = contralateral (opposite side)

36. Prefixes for Numbers • Prim/i- = first • primitive (occurring first in time) • Bi-= two, twice • bicuspid (a tooth with two points) • Tetra- = four • tetrahedron (a figure with four surfaces)

37. Prefixes for Colors • Cyan/o- = blue • cyanosis (bluish discoloration of the skin due to lack of oxygen) • Leuk/o-= white, colorless • leukoplakia (white patches in the mouth) • Xanth/o- = yellow • xanthodermia (yellow discoloration of the skin)

38. Negative Prefixes • A-, an- = not; without • aseptic (free of infectious organisms) • Dis-= absence, removal, separation • dissect (to separate tissues for anatomical study) • Non- = not • noninfectious (not able to spread disease)

39. Prefixes for Direction • Ad- = toward; near • adhere (to attach or stick together) • Per-= through • percutaneous (through the skin) • Trans-= through • transfusion (introduction of blood or blood components into the blood stream)

40. Prefixes for Degree • Hyper- = over, excess, abnormally high • hyperventilation (excess breathing) • Hypo-= under; below • hypoxia (decreased oxygen in the tissues) • Super- = above, excess • supernumerary (in excess number)

41. Prefixes for Size and Comparison • Iso- = equal, same • isograft (graft between two genetically identical individuals) • Micro-= small • microscopic (extremely small; visible only through a microscope) • Re- = again; back • regurgitation (backward or return flow)

42. Prefixes for Time and/or Position • Ante- = before • antenatal (before birth) • Pro-= before, in front of • prodrome (symptom that precedes a disease) • Post- = after, behind • postmenopausal (after menopause)

43. Prefixes for Position • Ec-, ecto- = out; outside • excise (to cut out) • End/o= in; within • endoscope (device for viewing the inside of a cavity or organ) • Mes/o- = middle • mesencephalon (midbrain)

44. Body Structure

45. Planes of Division • Frontal plane • Coronal plane • Divides body into anterior and posterior parts

46. Planes of Division • Sagittal plane • Divides body into right, left portions • If plane cuts midline, called midsagittal or medial plane

47. Planes of Division • Transverse plane • Divides body into superior, and inferior parts

48. Anatomical Directions • Anterior (ventral): toward front of body • Posterior (dorsal): toward back of body • Medial = toward midline of body • Lateral = toward side of body • Proximal = nearer to reference point • Distal = farther from reference point

49. Body Cavities • Dorsal cavity contains: • Cranial cavity and Spinal cavity • Ventral cavity contains: • Thoracic cavity • Diaphragm • Separates thoracic and abdominal cavity • Abdominopelvic cavity: • Abdominal cavity • Pelvic cavity • Peritoneum

50. Body Regions Imaginarily divided into 9 regions • Midline sections: • Epigastric = above stomach • Umbilical = umbilicus or navel • Hypogastric = below the stomach • Lateral sections: • Right and left hypochondriac • Positioned near ribs, specifically cartilages • Right and left lumbar • Positioned near small of back (lumbar region) • Right and left iliac • Named for upper bone of hip (ilium) • Also called inguinal region (referring to groin)