Pathophysiology Exam I Flashcards
Pathology
study of the change in body tissue and organs due to disease
Physiology
study of characteristics and function of a living organism
Pathophysiology
study of human physiologic function in disease; abnormal functioning of organs in disease
Symptom
a subjective indication of a disease or a change in condition as perceived by the client
Sign
an objective finding as perceived by the examiner
Etiology
cause of disease
Idiopathic
unknown cause
Homeostasis
main goal of the body, maintains stable equilibrium and regulates the body
three structures in the brain maintaining homeostasis
- medulla (respiratory and circulatory)
- pituitary gland (growth and reproduction
- reticular formation (brain stem)
Plasma Membrane
- “bouncer” of the cell
- controls the composition of the space or compartment they enclose
- controls movement of substances from one cell to another
- cellular mobility and maintenance of cellular shape
- exert a powerful influence on metabolic pathways
structure of plasma membrane
- cavolae – outer surface, serve as a storage site for receptors and provides route of transport into the cell
- lipids – bilayer of basic components, serve as a barrier but allows transport of oxygen and carbon dioxide
function of plasma membrane
- recognize and bind units
- pores of transport channels
- electrolytes and fluid balance
- cell surfaces markers identify a cell to another
- cell adhesion molecules that allow cells to join together and form attachments
- catalyst of chemical reactions
Endocytosis
plasma membrane “taking in” – bringing food into the cell
Pinocytosis
ingestion of fluid – drink the fluid brought in by the endocytosis
Phagocytosis
ingestion of large particles – eat the food brought in by endocytosis
Exocytosis
release intracellular substances into extracellular matrix – kicks out extra substances
Passive Transport
- small, uncharged molecules move easily through semipermeable membrane
- driven by osmosis, hydrostatic pressure, and diffusion
- DOES NOT REQUIRED ENERGY
Active Transport
Moving of large molecules requiring life, biologic activity and ENERGY
Diffusion
SOLUTES moves through a concentration gradient from an are of high concentration to an area of low concentration
Filtration
Movement of water and solutes through a membrane due to a pushing force on either side
Hydrostatic Pressure
- mechanical force of water pushing against cellular membranes
- PUSH PRESSURE
- counteracted by oncotic pressure to maintain homeostasis
Osmosis
movement of WATER down a concentration gradient across a semi-permeable membrane from high water concentration to lower water concentration
Osmotic Pressure
amount of hydrostatic pressure required to oppose the osmotic movement of water
Oncotic pressure
- PULL PRESSURE, opposes hydrostatic pressure
- example: hydrostatic pressure pushes water out to the body (causes edema) and oncotic pressure keeps the water in the blood stream
Isotonic
osmolality is the same as intracellular fluid
hypertonic
osmolality is high than intracellular fluid (shrinks)
Hypotonic
osmolality is lower than intracellular fluid (swells)
Cellular atrophy
- decrease in cellular size and function
- causes: disuse, nerve damage, impaired nutrition, aging, diminished blood supply, lack of endocrine stimulation
Cellular hypertrophy
- increased cellular size and function
- causes = excessive use of tissue
Cellular hyperplasia
- increased number of cells
- cells are dividing faster than dying off
Hypoxia
- single most common cause of cellular injury
- results from: reduced amount of oxygen in air, loss of hemoglobin or decreased efficacy of hemoglobin, decreased production of RBCs, diseases of the respiratory and cardiovascular system
- ischemia – most common cause of hypoxia
water accumulation
- malfunction of Na+/K+ pump
- cell swells with water
- enlargement of organs
- seen with almost all types of cellular injury
coagulative necrosis
- tissue hypoxia
- protein denature
- occurs primarily in kidneys, heart and adrenal glands
liquiefactive necrosis
- neurons and glial cells of the brain
- cells auto digested
- tissue liquefies and is walled off from healthy tissue
Caseous necrosis
- tuberculous pulmonary infection
- combination of coagulative and liquefactive necrosis
- necrotic debris surrounded by the wall of tissue
- “cheesy” debris
Fat necrosis
- breakdown of triglycerides
- occurs in breast, pancreas
- appears chalky, white
dry gangrene
tissue shrinks, definitive line between dead and alive tissue
wet gangrene
- cold, swollen tissue
- foul odor
- bacteria present
total body water
- intracellular fluid = 2/3 of total body water
- extracellular fluid = 1/3 of total body water
- interstitial fluid = tissue, outside of cell and blood vessel
- intravascular fluid – inside the blood vessel, outside the cell
capillary hydrostatic pressure
facilitates movement of water from capillary to interstitial space
capillary oncotic pressure
osmotically attracts water from interstitial back into capillary
interstitial hydrostatic pressure
facilitates inward movement of water from interstitial into capillary
interstitial oncotic pressure
osmotically attracts water from capillary into interstitial space
Atrial Natriuretic Peptide
- hormone increases rate of excretion of Na+ in urine
- hormone synthesized and stored in atrial muscle
- receptors in atria are stimulated in response to increased blood volume
Edema
- excessive accumulation of fluid within the interstitial spaces
- related to fluid filtration from capillaries or lymph channels into tissues
- causes = increase in capillary hydrostatic pressure, decrease in plasma oncotic pressure, increases in capillary permeability, lymph obstruction
localized edema
usually limited to a site of trauma to a site of trauma or within a particular organ system
generalized edema
more uniform distribution of fluid in interstitial space
Sodium, Chloride, and water balance
- water balance is regulated primarily by antidiuretic hormone (made in pituitary, hold onto fluid) also known as vasopressin
- secreted during low blood pressure or decrease in circulating blood volume
- sodium is regulated by renal effects of aldosterone
stimuli for thirst
- cellular dehydration – osmoreceptors
- decreased blood volume - baroreceptors
- angiotensin II
- make them crave salt to increase thirst
Antidiuretic Hormone
- holds onto fluid
- vasoconstriction effect – increases BP
- prevents excretion of water by kidneys
renal regulation
- kidneys are the primary organs of fluid and electrolyte balance
- water balance is maintained through urinary excretion
renal tubules are stimulated by ADH and aldosterone to control the concentration of urine
RAAS
- renin, agiotension, aldosterone system
- purpose is to increase sodium and water reabsorption
- can cause vasoconstriction to increase BP
isotonic alterations
- occur when changes in total body water are accompanied by proportional changes in electrolytes
- number of particle is equal on both sides of the membrane
- fluid will not move in or out of cells
isotonic fluid loss
- hemorrhage
- severe wound drainage
- excessive diaphoresis