involves the study of functional or physiologic change in the body from disease processes. As a disease develops, the changes in the normal anatomy &/or physiology may be obvious or may be hidden, occurring at the cellular level. As such, pathophysiology includes some aspects of pathology.
Essential to identify any impact health care activities might have on a patient's condition, or how a patient's illness might complicate care.
Common cellular adaptations
a) atrophy, b) hypertrophy, c) hyperplasia, d) metaplasia, e) dysplasia, f) anaplasia, g) neoplasm
decrease in size. **CAUSES: reduced use, insufficient nutrition, decreased neurological or hormonal stimulation, and aging.
Increase in size. **CAUSES: additional work by tissue (EX enlarged heart), consistent exercise on skeletal muscle, and excessive hormonal stimulation.
Increased number. **CAUSES: compensatory mechanism, hormonal imbalance, increased risk of cancer possibility
One mature cell type replaced by different mature cell type. **CAUSES: Vitamin A deficiency, adaptive mechanism
Cells vary in size and shape, large nuclei, and rate of mitosis increased. **CAUSES: chronic irritation or infection, possibly pre-cancerous.
Cells are undifferentiated, have variable nuclei and cell structure, and numerous mitotic figures. **CAUSES: associated with malignancy, or cancer, tumor grades.
"New growth" tumor (benign, malignant) malignant=cancer.
Causes of cell damage
a) ischemia, b) physical agents, c) mechanical damage, d) chemical toxins, e) microorganisms, f) abnormal metabolites, g) nutritional deficits, h) fluid/electrolyte imbalance
death of a group of cells
Area of necrotic tissue that has been invaded by bacteria.
Used by the body to protect itself from anj injurous agent. may be specific or non-specific.
1st Line of defense
Skin or mucous membrane
2nd Line of defense
Phagocytosis and inflammation (non-specific)
3rd Line of defense
Immune system (specific)
Lack of oxygen
Excessive temperature or radiation
Bacteria, viruses, and parasites
Normal defense mechanism a) Localizes and removes injurous agent, b) removes cellular debris, c) initiates healing process, d) Allows restoration of structure and function, e) regeneration of damaged tissue must occur to have complete restoration of function.
Systemic affects of inflammation
a) mild fever, b) malaise, c) headache, d) anorexia
May follow an acute inflammation who's cause has not been completely sured OR a chronic irritation (smoking)
Develops immediately and lasts a short time
Cardinal Signs and Symptoms of Inflammation
a) erythema, b) heat, c) sweling, d) pain
1) Damaged tissues release histamines, increasing blood flow to the area. 2) Histamines cause cappillaries to leak, releasing phagocytes and clotting factors into the wound. 3) Phagocytes engulf bacteria, dead cells, and cellular debris. 4) Platelets move out of the cappillary to seal the wounded area.
Inflammation as it relates to PT
Plays a vital role in the healing process. PTA should support the healing process and encourage pts to do the same.
Healing by 1st intention
Healing by 2nd intention
large open wound (slower)
Healing process that occurs in damaged tissue in which cells are capable of mitosis. Damaged tissue is replaced.
1) Begins with blood clot, then inflammation. 2) After 3-4 days phagocytes, monocytes and macrophages have removed debris. 3) Granulation tissue grows in the gap. 4) Epithelial cells undergo mitosis extending across the wound. 5)Fibroblasts produce collagen (scar tissue).
Fills the defect or gap in tissue. Overgrowth of scar tissue can cause a) loss of ROM, b) contracture (fixation and deformity of joint), c) adhesions (band of scar tissue joining 2 surfaces that are normally separated), d) hypertrophy and ulceration.
Factors that affect tissue healing
1) growth factors, 2) health, 3) presence of comorbidalities, 4) tobacco and caffeine, 5) nutrition, 6) type of tissue, 7) local or systemic infection, 8) medical treatment
Effect of prolonged immobilization
Tissue dehydrates and becomes less elastic, less plastic, and more brittle. Capsular structures (ligaments) become stiff and weak.
1) specific defense, 2) Responds to specific substances, cells, toxins, or proteins, 3) Detects and destroys unknown material, 4) Demonstrates tolerance by ignoring self cells, 5) Recognizes specific antigens as foreign (develops specific response and stores response in memory for future reference).
Covers the study of all aspects of the immune system. a) physiological, b) immunological disorders, c) characteristics and components of immune system
Benefits of a properly working Immune system
decreases risk of infection, provides protection, reduces susceptibility to common everyday infectious agents
Person's own body develops antibodies, or T cells, in response to specific antigen introduced into body.
active natural immunity
direct antigen exposure **memory
active artificial immunity
Antibodies transferred from one person to another.
Passive natural immunity
invitro and breast milk **no memory
Passive artificial immunity
Rabies or anti-venom, immunoglobulin ** no memory
1st line of defense. Acts as barrier.
Tissue transplant rejection causes
Occurs when the immune system is responding to the foreign tissue resulting in destruction of the organ.
Tissue transplant rejection treatment
Involves immunosuppression techniques that reduce the immune response and prevent rejection. -drug intervention
Type I- Hypersensitivity
Allergic reactions, hay fever, food allergies, atopic dermatitis (eczema), asthma
Type II- Cytotoxic Hypersensitivity
Reaction to different blood type (Rh factor)
Type III- Immune Complex Hypersensitivity
Glomerulnephritis, rheumatoid arthritis
Type IV- Cell-mediated or Delayed Hypersensitivity
TB test, contact dermatitis, allergic skin rash
Severe life-threatening. Hypersensitivity reaction resulting in: 1) decreased BP, 2) airway obstruction, 3) severe hypoxia.
itching, tingling, coughing, difficulty in breathing, weakness, dizziness, fainting, fear/panic, edema in eyes, lips, tongue, hands, feet, hives, loss of conciousness
Occur when individuals develop antibodies to their own cells or cellular material and these antibodies then attack the individual's tissues (EX lupus)
HIV risk in healthcare professions
Great concern over, but little evidence of, transmission to healthcare workers from infected patients other than by accidental injury or the presence of open skin lesions. Should assume risk of some infection from contact with bodily fluids and follow universal precautions.
chronic infectious disease caused by HIV which destroys helper T-cell lymphocytes, causeing loss of the immune response and increase susceptibility to secondary infection and cancer. Prolonged latent period followed by period of active infection.
Fluids entering should equal fluids exiting to maintain balance