PHS 4300 Pathophysiology Final Exam Study Guide 2020 | PHS4300 Pathophysiology Final Exam Review

PHS 4300 Pathophysiology Final Exam Study Guide 2020 PHS4300 Pathophysiology Final Exam Review LAB VALUES: ▪ RBC: 4,200,000-5,400,000 4,800-10,800 ▪ Platelet: 150,000-400,000 12-16.5 37-50% ▪ K+: 3.5-5.0 ▪ Na+: 135-145 ▪ Ca+: 8.5-10.5 1.8-3.0 98-106 8-20 ▪ Creatinine: 0.6-1.2 7.35-7.45 Urine Specific Gravity- CELLULAR INJURY ▪ Hypoxia: an inadequate supply of oxygen to tissue that is below physiologic levels despite adequate perfusion of the tissue by blood; cells revert to anaerobic metabolism, causing the accumulation of lactic acid and dropping of pH. Affects all the cells in the body. Causes power failure in the cell, with effects on the cell’s functional and structural components. When Aerobic stops, less ATP is produced causing the Na/K pump to not run fast enough, this is return keeps Na in the cell and K out of the cell causing it to swell. Anaerobic metabolism produces lactic acid, the acid damages cell membranes, intracellular structures, and DNA. w/out O2 = loose ability to have ATP = death need to have ATP to run Na/K pump Ischemia: decreased blood supply to a body organ or part, usually due to functional constriction or actual obstruction of a blood vessel; can cause necrosis if not corrected. Characterized by impaired removal of metabolic end products such as lactic acid as well as impaired blood supply. Decreased blood flow is caused by circulatory disorders. Affects blood flow through small numbers of blood vessels and produces local tissue injury. Changes: Gangrene – large area of necrotic tissue o Dry – lack of arterial blood supply but venous flow can carry fluid out of tissue. From heart to extremities o Wet – lack of venous flow lets fluid accumulate in tissue. From extremities to heart. Tissue tends to liquefy and infection is likely – foul odor o Gas – clostridium infection produces toxins and H2S bubbles (hydrogen sulfide) – from soil Risk factors for cellular changes: Physical agents: o Mechanical forces: causes injury or trauma that split and tear tissue, fracture ones, injure blood vessels, disrupt blood flow; examples: car accident o Extremes of temperature: causes damage to the cell, its organelles, and its enzyme systems Low intensity heat- causes cell injury by inducing vascular injury, accelerating cell metabolism, inactivating temp-sensitive enzymes, and disrupting cell membranes. Intense heat- causes coagulation of blood vessels and tissue protein occurs. Cold- Increases blood viscosity and indueces vasoconstriction by direct action on blood vessels and through reflex activity of the SNS. Freezing temps- Results from a combination of ice crystal formation and vasoconstriction. The decreaed blood flow leads to capillary stasis and arteriolar and capillary thrombosis. o Electrical: electrical current. Affects the body through extensive tissue injury and disruption of neural and cardiac impulses. The effect is determined by voltage, type of current, amperage, resistance of intervening tissue, pathway of current and duration of exposure. Chemical agents and drugs Can injure cell membrane, block enzymatic pathways, coagulate cell proteins, and disrupt the osmostic & ionic balance of the cell. Biologic agents: viruses and parasites. The only agent that is able to replicate and continue to produce injury. Ionizing radiation. Causes ionization of molecules and atoms in the cell, directly hitting the target molecule of cells, or produces free radicals that interact with critical cell components. Manifestations result from acute cell injury, dose-dependent changes in the vessels that supply the irradiated tissue and fibrotic tissue replacement. Nutritional imbalances o Excess: Obesity and diets high in fats- predispose pesons to atherosclerosis. o Deficiencies: Starvation- deficiency of all nutrients and vitamins which causes tissue damage. Cellular changes: Atrophy: a wasting of size, often accompanied by a decrease in function, or a cell, tissue, or organ; occurs in normally formed organs; adaptive and reversible. A decrease in size of a tissue organ resulting from a decrease in cell size of the individual cells or in the number of cells. o General causes: disuse(related to workload, which causes decreased oxygen and protein synthesis), reduced functional demand, loss of trophic stimuli, insufficient nutrients, decreased blood flow, persistent cell injury(most commonly cause by chronic inflammation), and aging • Example: wearing a cast o Denervation atrophy is a form of atrophy in paralyzed limbs that results from lost of nervous system stimulation. o One of the hallmarks of aging, particularly in non republic cells such as the brain and heart, is cell atrophy. o Alzheimers: atrophy of cerebral cells. Non reversible. Hypertrophy: the enlargement or overgrowth of an organ that is due to an increase in the size of its cells. Results from an increase work load imposed on an organ or body part. Most commonly seen in cardiac and skeletal muscle tissue which cannot adapt to the increase in workload. Normal example: an increase in uterus size during pregnancy. Also caused by chronic exercise. Abnormal example: an increase in heart size to compensate for low heart rate or low blood pressure. o Physiologic hypertrophy: the increase in muscle mass associated with exercise o Pathologic hypertrophy: occurs as the result of disease conditions and may be adaptive or compensatory o Compensatory hypertrophy: is the enlargement of a remaining organ or tissue after a portion has been surgically removed or rendered inactive o Adaptive hypertrophy- Ex: the thickening of the urinary bladder from pro-longed obstruction. Hyperplasia: an abnormal multiplication or increase in the number of normal cells of a body part; occurs in tissues with cells that are capable of mitotic division; adaptive and reversible. Is an important response of connective tissue in wound healing which contributes to wound repair. Hyperplasia is a controlled process that occurs in response to an appropriate stimulus and ceases after the stimulus has been removed. o Physiological hyperplasia: can occur as the result of hormonal stimulation or increased functional demands, or as a compensatory mechanism • Example: breast and uterus during pregnancy. Result from estrogen stimulation. • Example of compensatory hyperplasia: the regeneration of the liver that occurs after partial hepatectomy. o Nonphysiologic hyperplasia: due to excessive hormonal stimulation or the effects of growth factors on target tissues • Example: excessive estrogen production causes endometrial hyperplasia. And also the increase of the prostate glands in BPH. Dysplasia: the alternation in size, shape, organization, and appearance of adult cell types; minor degrees of dysplasia are associated with chronic irritation or inflammation; adaptive; precursor of cancer, but can revert to their former structure and function, so they do not always cause cancer o Strongly implicated as a precursor of cancer, but dysplasia is an adaptive process and as such does not necessarily lead to cancer in many cases, dysplastic cells revert to their former structure and function. o Example: pap smear – can be meta or dysplasia Metaplasia: represents a reversible change in which one adult cell type (epithelial and mesenchymal) is replaced by another aduly cell type. usually occurs in response to chronic irritation and inflammation and allows for substitution of cells that are better able to survive under circumstances in which a more fragile cell type might succumb. The conversion cell types never overstep the boundaries of the primary group of tissue. For example, 1 type of epithelial cell may convert to another type of epithelial cell but cannot convert to connective tissue cell. o Example: the adaptive substitution of stratified squamous epithelial cells for the ciliated columnar epithelial cells in the trachea and large airways in habitual smokers o Example: acid reflux STRESS AND DISEASE* Stress decreases the immune response. Encompasses 3 basic concepts: homeostasis, stress & stress response, and adaptation to stress. Sympathetic Nervous System: “fight or flight” response; increases with stress. The most rapid stress response. Epinephrine and Norepinephrine (from adrenal medulla) are both released, and attach to the adrenergic receptors on cells. Norepi and epi – catecholamines - decrease insulin release and increase glucagon release resulting in increased glycogenolysis, gluconeogenesis, lipolysis, proteolysis, decreased glucsose uptake, increased HR, vascular smooth muscle contraction, relaxation of bronchial smooth muscle, BP restores, blood flow to skin, guts, and kidneys restored, skin becomes pale, urine production decreases, GI activity decreases.