Pathophysiology Flashcards
Pathophysiology
Study of the functioning of an organism in presence of disease
Cell
Basic self sustaining unit of the human body
Three Main Parts of Cell
Cell Membrane
Cytoplasm
Nucleus
Cell Membrane
Consists of fat and protein
-surrounds dell and protects nucleus and organelles
Organelles
Functional structure within the cells cytoplasm
Inside of Organelle
Ribosomes, ER, Golgi Complex, Lysosomes, Peroxisomes, Mitochondria, Nucleus
Ribosomes
Contain RNA and protein
- Responsible for controlling cellular activities
- interact with other amino chains to form proteins
- when attached to ER they for, rough ER
ER
Network of tubules, vesicles and sacs
- Smooth ER builds fats
- Rough builds proteins
Golgi Complex
Synthesis and packaging of various carbohydrates and complex protein molecules such as enzymes
Lysosomes
Membrane bound vesicles that contain digestive enzymes
-intracellular digestion that breaks down organic debris, (bacteria) that have been taken into the cell
Peroxisomes
Found in high concentrations in liver and neutralize toxins such as alcohol
Mitochondria
Metabolic center of cell no produce ATP, major energy source in the cell
Nucleus
Contains DNA in the chromosomes and RNA
Epithelium
Covers external surfaces and lines hollow organs such as intestines, blood vessels and bronchial tubes
- absorb nutrients
- secrete body substances (sweat)
Endothelial Cells
Epithelial cells that line vessels
-help regulate blood flow and have a role in blood clotting
Connective Tissue
Binds other types of tissue to one another
- separated by non living extracellular matrix consisting of protein fibers and fluid
- collagen main protein in fluid
- adipose tissue is a connective tissue mainly made of large amounts of lipids (fats)
- blood is connective
Muscle Tissue
Characterized by ability to contract -Enclosed by fascia, envelope of fibrous material Skeletal: striated volunTary Cardiac: striated involuntary Smooth: nonstriated involuntary
Nerve Tissue
Transmit nerve impulses
Central and Peripheral
Homeostasis
Same and steady
Apoptosis
Normal cell death in which old cells are replaced by new cells
Cell Signaling
Way that the cells communicate electrochemically to each other by releasing molecules (such as hormones) that bind to protein receptors on the cell surface.
In result, a triggered chemical reaction occurs and initiates a biological reaction
Baroreceptors
Respond to changes in pressure usually within heart or main arteries
Chemoreceptors
Sense changes in chemical composition of the blood, especially reduced oxygen levels and elevated CO levels
Five Primary Ways to Release Heat
Convection, conduction, evaporation, radiation and respiration
Ligand
“To tie or bind”
Are molecules that bind to receptor sites to form more complex structures
-Endogenous or Exogenous Ligands: produced by body or given into body
Hormones
Substances found in tiny amounts by one specialized group of cells and then carried to another organ or group of cells and then carried to another organ or group to perform regulatory functions
Endocrine Hormones
(Thyroid hormones and adrenal) carried to their target by the blood
Exocrine Hormone
Reach target by a specific duct that opens into an organ (stomach acids and perspiration)
Paracrine Hormones
(Histamines) diffuse through intracellular spaces to reach their target
Electrolytes
Dissolved mineral salts that dissociate in a solution yielding ions (sodium, potassium, clalcium, chloride)
-have important role in cell signaling and in generating the Nervous System action potential
Ions
Positive charge: cation
Negatively charged: anion
Body fluids are suppose to be electrically neutral
Atrophy
Decrease in cell size due to loss of sub cellular components which results in a decrease in the size of the organ or tissue
- actual number of cells remain unchanged but decrease in an attempt to cope with a new steady state
- coasted immobilized limb loses muscle and shrinks in size
Hypertrophy
Increase in the size of the cells due to synthesis of more subcellular components which creates an increase in size of a tissue or organ
-left ventricle may hypertrophy from increased pressure
Hyperplasia
Increase in actual number of cells in an organ or tissue usually resulting in increase in size of organ or tissue
-a callus is hyperplasia of the keratinized layer of the epidermis in response to increase friction or trauma
Dysplasia
Alteration of size shape and organization of cells is most often found in epithelial cells where they have undergone atypical, irregular inflammation or irritation.
-development of cervical dysplasia in women is strongly associated with exposure to certain viruses
Metaplasia
Reversible cellular adaptation in which one or more cell type is replaced by another adult cell type.
-the airway of smokers and cilia may be replaced by meta plastic epithelium after burned away
Body Weight
50-70% is fluid
Intracellular Fluid
75% of body weight in fluid
Extracellular Fluid
25% of body weight in fluid
- interstitial and intravascular
- interstitial: surrounds tissue cells and includes cerebrospinal, and synovial fluid
- intravascular: found within blood vessels but outside the cells
Solvent and Solute
Water and Salt
Passive Transport
Movement of substance by diffusion from area of high concentration to area of low concentration
Active Transport
Movement via transport molecules, or pumps, that require energy to move substances from an area of low concentration to area of high concentration
Osmosis - how water moves between ICF and EXF
Movement of a solvent from an area of low solute concentration to an area of high solute concentration through a selectively permeable membrane to equalize solute to solvent
Hypertonic Solution
Higher osmotic pressure due to having a higher solute concentration
Hypotonic Solution
Lower osmotic pressure due to having a lower solute concentration
Isotonic Solutions
Normal Saline e.g and lactate ringers
Intracellular Fluid controlled In two ways
By proteins and compounds that cannot escape and the sodium potassium pump
-most intracellular charges are negatively charged so they attract positively charged ions like potassium and because potassium is osmotically active, they can pull water into the cell. Even until it ruptures.
Sodium Potassium Pump
Responsible for checks and balances of water being brought in by continuously removing three sodium ions from the cell for every two potassium cells that are moved back into the cell
- if Pump is damaged due insufficient potassium, sodium accumulates and causes the cells to swell
- ATP used to make the exchange happen
Plasma
Makes up 55% of blood
91% water and 9% plasma proteins
-plasma proteins: albumin which maintains osmotic pressure; and fibrinogen and prothrombin which assist with clotting
Capillary Hydrostatic Pressure
Pushes water out of capillary into interstitial space. Cause pressures differ, more water is pushed out of arterial end and more is absorbed through venous end.
Tissue Colloidal Pressure
Draws fluid into the interstitial space
Edema
Occurs when excess fluid builds up in interstitial spaces -Many causes: increased capillary hydrostatic pressure from Allergic Reactions Venous Obstruction Increased vascular volume Increase adrenocorticol hormones Sodium retention Pregnancy Gravity from long sitting
ADH
Antidiuretic Hormone or “vasopressin”
RAAS
Renin-angiotensin-aldosterone system
- complex feedback mechanism responsible for kidneys regulation of sodium in the body
- high it is secreted, low it is reabsorbed
Osmoreceptors
Monitor extracellular fluid osmolarity
- located primarily in Hypothalmus
- when extrcellular osmolarity is too high they stimulate production of ADH
Blood Osmolarity
When increased pituitary gland secretes ADH which stimulates the kidneys to reabsorb water decreasing the osmolarity of the blood
Renin
Protein that released by kidneys into blood stream as a response of changes in blood pressure, blood flow, and globular filtration rate.
When renin is released, it converts plasma protein angiotensinogen to angiontensin 1.
In the lungs, angiotensin 1 is rapidly converted to angiotensin 2 by Agiontensin-Converting Enzyme.
Angiotensin 2 then stimulates sodium resorption by renal tubules and constricts renal blood vessels, slowing kidney blood flow and decreasing the glomerular filtration rate.
In result, less sodium is reabsorbed in the blood
RAAS
Renin + plasma protein angiotensinogin = agiontensin 1 => lungs + ACE => angiotensin 2 + renal tubules = sodium reasorption
Baroreceptors
Monitor hydration and are located in the carotid artery, kidneys, and aorta
Volume sensitive receptors
Located in the atria so when intravascular pressure increases, the atria stretches and causes a release of atrial natriuretic proteins
Natriuretic Proteins
Increase when the body contains too much sodium and water which inhibit the ADH and promote excretion of sodium and water by the kidneys
Sodium and Chloride
Where sodium goes, Chloride follows
-together they make table salt but when in water they dissasociate
Tonicity
Tension exerted on a cell as a result of water movement across the cell membrane
Hyponatremia
Low sodium level caused by sweating, exercise, vomiting, diarrhea
Potassium
Major intracellular cation necessary for muscle control, regulation of all muscles, acid base balance, and maintain osmolarity in cells
- hypokalemia: from fluid loss, shifts into cells from insulin, Epi and others. Causes, muscle weakness, fatigues, muscle cramps,
- hyperkalemia: renal failure, ace inhibitors, nsaids inhibit secretion. Causes, peaked t waves can administer calcium, Albuterol, fluids, and bicarbonate
Calcium
98% found in bones
- provides strength and stability for collagen and ground substances.
- calcium enters through GI tract and is absorbed in the blood
- hypocalcemia: hypoparathyroidism, alcoholism, diuretic Therapy. Causes, spasm of skeletal muscles, cramps, laryngospasm, seizures, prolongation of QT interval
- hypercalcemia: excess ingestion, hyperparathyroidism, cancers. Causes, constipation and frequent urination. Give fluid of NaCl.
PTH
Parathyroid Hormone, regulates uptake of calcium in intestines, kidneys, and works with calcitirol to stimulate osteoclasts activity
Acid
Can give up hydrogen ion
- less than 7 ph
- H+
Base
Can accept hydrogen ion
- OH-
- greater than 7 ph
Acidosis
Kidneys secrete H+ and retain K+
Alkolosis
Kidneys secrete K+ and retain H+
Buffers
Molecules that modulate changes in pH by neutralizing excessive buildup of acids and bases
Bone Buffer
Bone acts as buffer to absorb excess acids and release calcium into the circulation
Strong or Weak
Depends on how it disassociates in water
Buffers
Proteins, phosphate ions, and bicarbonate
Eliminate Acid
Excess acids are given off in the form of gas from the lungs
Eliminate Base
Mainly give excess base off from kidneys
Three primary buffers
Bicarbonate in blood, respiratory, and renal system
Bicarbonate
Forms with H+ To from carbonic acid and disassociates in water to form carbon dioxide to be exhaled
Four types of OF presentations of acid base imbalance
Respiratory alkalosis/acidosis
Metabolic alkalosis/acidosis
Respiratory Acidosis
Hypoventilation
Causes: Signs and Symptoms
airway obstruction. Red skin
Cardiac arrest. CNS depression
Opiate OD. Bradypnea
Drowning. Nausea vomiting
CHF
Head Injury
Chest Trauma
CO poisioning
-can cause fatal disrhythmias due to accumulation of potassium
-COPD causes acidosis over time as inhibition of gas exchange occur
Respiratory Alkalosis
Caused by hyperventilation
Causes: S&S:
Drug overdose, aspirin. loc
Fever. Light headed ness
BVM. Carpalpedal spasm
Hypocalcemia. Tingling face lips
Nausea Vomiting. Chest pain
Anxiety. Blurred vision
Metabolic Acidosis
Any acidosis not caused by respiratory
-Lactic Acidosis: anaerobic metabolism from hypoperfusion of tissues
-Ketoacidosis: develops when cells are forced to switch to use fatty acids as energy
-Acetlysalicylic OD: aspirin, 10-30g, is overdose, stimulates brain to hyperventilate and renal compensatory
-Alchoholic Keto: anti freeze and wood alcohol
Causes: vasodilation, CNS depression, headaches, hot skin, tachypnea, nausea vomiting
Metabolic Alkalosis
Excessive loss of acid from increased urine output or from acid in stomach
-Stomach loses acids
-Drinking large amounts of water
-Alkaline substances such as atacids
Causes: confusion, tremors and cramps, bradypnea, hypotension
Hypoxia Injury
Caused from air, CO, red blood cell loss, or cyanide poisoning
- when hypoxia for more than minutes, cells produce mediators that are harmful to other tissues
- free radicals produced as mediator: are missing an electron so the attack cells to find missing electron
Infectious Injury
Virulence: measures Disease causing ability of a microorganism
Bacteria
Phagocytes: white blood cells that engulf and consume foreign material such as cellular debris and microorganisms
Pyrogens
Released by white blood cells when they attach to a cell to destroy causing a fever
Apoptosis
Normal cell death
Necrosis
Result of morphologic changes that occur following cell death in living tissues
Long QT Syndrome
Cardiac conduction system abnormality characterized by prolongation of the QT interval on ECG
-Causes syncope, death
Gout
Abnormal accumulation of Uris acid due to a defect in metabolism
Kidney Stones
Small amounts of Uris acid or calcium salts that accumulates
Cardiogenic Shock
Occurs when heart can not circulate enough blood to maintain adequate peripheral oxygen delivery.
-Causes: MI, Large Ventricular Defect, Dysrhythmias
Obstructive Shock
Blood flow becomes blocked in heart or great vessels
-Causes: tamponade, tumor, PE
Hypovolemia Shock
Circulating blood Volume is not enough to deliver adequate oxygen and nutrients to the body
-Causes: fluid loss, vomiting/diarrhea, blood loss
Distributive Shock
Wide Spread of dilation of vessels
-Causes: anaphylactic, sepsis, neurogenic ( spinal cord injury)
Lymphatic system
Network of capillaries and ducts that help maintain fluid environment of the body
Lymph
Thin watery substance that bathes tissues of the body
Five Types of Leukocytes
- Basophils: histamine granules released during inflammation
- Eosinophils: damage or kill invaders and can trigger bronchospasm
- Neutrophils: most abundant ,55-70% of leukocytes, protect body against invasion, and infection. They are readily attracted to foreign antigens and eat them by phagocytosis
- Monocytes: produce macrophages which scavengers for the tissues
- Lymphocytes: mediate acquired immune response
Antigen
Foreign substance
Antibody
Binds to an antigen to hopefully destroy it
Cell Mediated Immune Response
Characterized by the formation of a population of lymphocytes that can attack and destroy foreign material
T-cell Lymphocytes
Recognize antigens and contribute to the immune response in two ways
1: by secreting cytokines that attract other cells
2: by becoming cytotoxic and killing infected or abnormal cells
Killer T Cells
Destroy the antigen
Help rid the body of cells that have been infected by viruses and cells that have been transformed into cancer cells
Helper T Cells
Activate many immune cells
Suppressor T Cells
Suppress the activity of other lymphocytes so they do not destroy normal tissue
Memory T Cells
Remember the reaction for the next time it is needed
Lymphokine-producing cells
Work to damage cells, they destroy cells that have been infected by virus
Active Hyperemia
Causes increased vascular pressure which causes the blood vessel to expand in an inflammatory response
- when the wall expands it becomes thinner causing fluid to leak from the vessel causing edema
- results in warm to touch because the vessels dilate and are closer to the skin
Mast Cells
During inflammation they degranulate and release a variety of substances
-primary stimuli is trauma, chemical agents, and immunologic substances ( antigen )
Mast Cells cont.
Following degranulation, mast Cells release vasoactivamines which increase vascular permeability, vasodilator, and can cause bronchoconstriction, nausea, vomiting
-histamine and serotonin: released quickly
Prostoglandins
Mast Cells synthesize these
- comprise about 20 lipids that are composed of fatty acids.
- found in vertebra tissue and act as messengers in reproduction, inflammatory response and pain from trauma
- aspirin and nsaids inhibit prostaglandin synthesis which leads to reduced inflammation and pain
Coagulation System
Vital role in formation of blood clots in the body and facilitates repair
Coagulation cont.
Inflammation triggers the coagulation cascade initiating a series of complex reactions that encourage fibrin formation
-simultaneously the fibronolysis cascade is activated to dissolve the fibrin and create fibrin split products
Fibrin
Is the protein that bonds to form the fibrous compound of a blood clot
Kinin System
Leads to formation of The vasoactive protein bradykinin from kallikrein.
Kallikarein found in plasma, urine, and tissue inactive but when active can cause dilation, change BP, modulate salt and water excretion by kidneys
Polymorphonuclear Neutrophils
Inflammatory cells that involve both an intravascular and extravascular phase
Intravascular
Move to the sides of blood vessels and attach to endothelial cells
Extravascular
Leukocytes move to the site of inflammation and kill organism
Margination
Loss of fluid from blood vessels into inflamed or infected tissue gives blood remaining in vessels more viscosity which slows the flow of blood and produces stasis
Activaton
Mediators of inflammation trigger the appearance of selectins which stimulates bone marrow to produce more WBC and increase Leukocytes count
Adhesion
PMN’s attach to endothelial cells by selections and integrins
Transmigration
The pmn’s permeate the vessel wall, passing into interstitial spaces
Chemotaxis
PMN’s move toward inflammation
Hypersensitivity
Response of the body to any substance to which a patient has increased sensitivity
Allergy
Hypersensitivity reaction to presence of an allergen
Autoimmunity
Production of antibodies or T cells that work against the tissues of ones own body producing hypersensitivity reactions or autoimmune diseases
Isoimmunity
Formation of T cells in response to others tissues
-seen with rejection of t cells
Rh Factor
Antigen present in the red blood cells of about 85% of population
Must be Rh positive or negative to receive that type of blood along with ABO
Type A
Contains type A surface antigens and plasma containing B antibodies
Type B
Contains type B surface antigens and plasma containing A antibodies
Type O
Have neither A or B surface antigens but have type A and B antibodies
Stress
General Adaptation Syndrome
Stage 1
Alarm:
Release catecholamines
Stage 2
Resistance:
Body adapts to release of catecholamines by releasing corticosteroids hormones that increase the blood glucose and maintain blood pressure
-Glucocorticoid and Mineralcorticoid
Body also increases metabolism to compensate
Stage 3
Exhaustion:
Adrenal Glands become depleted giminishing level of glucose resulting in mental and physical exhaustion
Hypothalamic-adrenal-pituitary axis
Major part of the neuron doctrine system that controls reaction to stress
