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Patho Midterm 1
Question | Answer |
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pathophysiology | the study of the underlying changes in body physiology that results from or is caused by disease or injury. |
etiology | cause of disease |
idiopathic | disease of unknown cause |
iatrogenic | disease as a result of medical/surgical treatment |
nosocomial | disease that results from being in a hospital environment |
diagnosis | naming or identification of a disease |
clinical manifestations | evidence of disease |
sign | objective alterations that can be observed or measured by another person |
symptom | subjective experience by the patient |
prognosis | expected outcome of a disease |
acute disease | sudden appearance of signs or symptoms of disease(short time period) |
chronic disease | slow development, long time period of signs or symptoms of disease |
remissions | periods when symptoms disappear or diminsh significantly |
exacerbations | periods when symptoms are much worse/severe |
complication | onset of another disease in a person who is already coping with a pre-existing disease |
sequelae | unwanted outcomes of having disease or result of trauma |
prodrome/prodromal period | time(usually at illness start) when patient has vague symptoms before onset of specific disease signs and symptoms |
insidious | slow, vague, nonspecific feelings of change in the body |
latent period | time during which no symptoms are apparent, but disease is present |
syndrome | group of symptoms and/or signs that occur together that may be caused by interrelated problems or a specific disease |
disorder | abnormality of function |
risk factors/predisposing factors | increase probability that disease will occur (but are not causes) |
precipitating factor | a condition or event that causes a pathologic event or disorder |
purpose of DNA | synthesis of proteins- genetic code |
mutation | any alteration of genetic material |
pyrimidines | cytosine and thymine |
purines | adenine and guanine |
transcription | RNA is synthesized from the DNA template, results in formation of mRNA, RNA Polymerase binds to promoter and txn continues until termination sequence |
translation | process by which RNA directs the synthesis of a polypeptide |
Chromosomes | condensed DNA and protein(chromatin) into dark staining organelles. Contain genes |
genes | basic units of inheritance |
somatic cells | all cells besides gametes. Contain 46 chromosomes(23 pairs). Diploid Cells |
Gametes | sperm and egg cells. Contain 23 chromosomes. Haploid Cells. Contain one member of each chromosome pair |
autosomes | the first 22 of the 23 pairs of chromosomes in males and females. Homologous |
Homologous Chromosomes | identical chromosomes |
sex chromosomes | remaining pair of chromosomes(23rd pair). In females it is XX and in males it is XY |
karyotype | ordered display of chromosomes |
Euploid Cells | have a multiple of the normal number of chromosomes |
Polyploid Cell | when a euploid cell has more than the diploid number |
Triploidy | a zygote having 3 copies of each chromosome (69 total) - polyploid |
tetraploidy | a zygote having 4 copies of each chromosome (92 total)- polyploid |
aneuploidy | a somatic cell that does not contain a multiple of 23 chromosomes |
Trisomy | a cell containing 3 copies of one chromosome |
monosomy | presence of only one copy of any chromosome (lethal) |
nondisjunction | Failure of homologous chromosomes or sister chromatids to seperate normally during meiosis or mitosis. Usually the cause of aneuploidy |
partial trisomy | only an extra portion of a chromosome is present in each cell |
chromosomal mosaics | trisomies occurring only in some cells of the body |
Down Syndrome | Trisomy 21. Mentally retarded, low nasal bridge, epicanthal folds, protruding tongue, poor muscle tone |
Trisomy X | female that has 3 X chromosomes. "Metafemales". Variable symptoms: sterility, menstrual irregularity, mental retardation |
Turner Syndrome | females with only one X chromosome. Absence of ovaries, sterile, short stature, webbed neck. edema, underdeveloped breasts, wide nipples, usually inherited from mother |
Klinefelter Syndrome | At least 2 X's and one Y. Can be XXY or XXXY. Male appearance, female like breasts, small testes, sparse body hair, long limbs |
Cri du Chat Syndrome | rare genetic disorder. Deletion of short arm of chromosome 5. Low birth weight, mental retardation, microcephaly |
deletions | broken chromosomes and lost DNA |
fragile sites | areas on chromosomes that develop distinctive breaks or gaps when cells are cultured |
fragile X syndrome | fragile site on long arm of the X chromosome. Associated with mental retardation. Higher incidence in males b/c they dont have another X to compensate. Females can be carriers. Caused by CGG repeats |
genetics | mechanisms by which an individuals set of paired chromosomes produces traits |
locus | position of a gene along a chromosome |
allele | a different form of a particular gene at a given locus |
homozygous | loci on a pair of chromosomes have identical genes/alleles |
heterozygous | loci on a pair of chromosomes have different genes/alleles |
genotype | the genetic makeup of an organism. "What the have" |
phenotype | the observable, detectable, or outward appearance of the genetics of an organism. "What they demonstrate" |
dominant allele | Allele with observable effects in a heterozygote. Capital Letter |
recessive allele | Allele with hidden effects in a heterozygote. Lowercase Letter. |
carrier | an individual who has a disease gene but is phenotypically normal |
pedigrees | summarizes family relationships and shows which members of a family are affected by a genetic disease |
proband | first person in the family diagnosed or seen in a clinic |
autosomal dominant disorder | abnormal allele is dominant, normal allele is recessive, and the genes exist on a pair of autosomes |
recurrence risk | the probability that parents of a child with a genetic disease will have yet another child with the same disease. Same for each subsequent child |
penetrance | the percentage of individuals with a specific genotype who also express the expected phenotype |
expressivity | variation in a phenotype associated with a particular genotype |
autosomal recessive disorder | abnormal allele is recesssive and a person must be homozygous for the abnormal trait to express the disease |
Sex Linked(X-linked) disorders | usually expressed in males because females have other X to mask abnormal gene. Recessive. Males have only one X chromosome so they are hemizygous for genes on the X chromosome. If they inherit a recessive gene, on Xm he will be affected |
polygenic | variation in traits caused by the effects of multiple genes |
multifactorial trait | variation in traits caused by genetic and environmental or lifestyle factors |
quantitative traits | traits that are measured on a continuous numeric scale |
5 types of adaptations | atrophy, hypertrophy, hyperplasia, metaplasia, dysplasia |
atrophy | decrease or shrinkage in cellular size(can lead to entire organ shrinkage). Most common in skeletal muscle, heart, secondary sex organs, brain. |
physiologic atrophy | occurs with early development (ex. thymus glad during childhood) |
pathologic atrophy | occurs as a result of decreases in workload, pressure, use, blood supply, nutrition, hormones, and nervous stimulation |
hypertrophy | increase in size of cells (and affected organ); most common in heart and kidneys. Due to protein accumulation |
triggers for hypertrophy | 1) Mechanical- stretch 2) Trophic- growth factors, hormones, vasoactive agents |
physiologic hypertrophy | occurs in response to heavy work; diminishes with lighter workload. Occurs when kidney adapts to removal of part of damaged kidney and during pregnancy with mammary glands and uterus |
pathologic hypertrophy | example is in the heart due to hypertension |
hyperplasia | increase in number of cells resulting form an increased rate of cellular division |
Compensatory Hyperplasia (Physiologic) | enables certain organs to regenerate . example is regeneration of liver cells. |
Hormonal Hyperplasia(Physiologic) | occurs chiefly in estrogen dependent organs such as uterus and breast. Hyperplasia(along with hypertrophy) allows these to enlarge. |
Pathologic Hyperplasia | abnormal proliferation of normal cells, usually in response to excessive hormonal stimulation or growth factors on target cells |
dysplasia | abnormal changes in the size, shape, and organization of mature cells; not a true adaptive process, often occurs in epithelial tissue of the cervix and respiratory tract |
metaplasia | reversible replacement of one mature cell type by another, sometimes less differentiated cell type. |
cellular injury | occurs if the cell is unable to maintain homeostasis. Can be reversible/recovery or irreversible/death. |
4 common biochemical themes of cell injury | ATP depletion, oxygen and oxygen-derived free radicals, calcium alterations, defects in membrane permeability |
ATP depletion | loss of mitochondrial ATP and decreased ATP synthesis; results in cellular swelling, decreased protein synthesis, decreased membrane transport, lipogenesis, loss of integrity of plasma membrane |
Oxygen and Oxygen derived free radicals | lack of oxygen leads to injury, free radicals(O2-,H2O2, OH.) cause destruction of cell membrane/structure |
Calcium Alterations | normally intracellular Ca concentrations are low; ischemia and chemicals cause an increase in cytosolic Ca++ concentrations. Causes intracellular damage |
Defects in membrane permeability | early loss of selective membrane permeability is found in all forms of cell injury |
3 common forms of cell injury | Hypoxia, free radicals/reactive oxygen species injury, chemical injury |
hypoxia | lack of sufficient oxygen; single most common cause of cell injury |
ischemia | reduced blood supply, not enough oxygen |
anoxia | total lack of oxygen |
Cellular Responses to Hypoxic Injury | decrease in ATP production, increased anaerobic metabolism, decreased glycogen, failure of sodium potassium pump and sodium calcium exchange, cellular swelling vacuolation, damage to membrane |
Free Radicals/Reactive Oxygen Species Injury (oxidative stress) | occurs when excess ROS overwhelms endogenous antioxidant systems. Cause damage by lipid peroxidation, membrane damage, increased permeability, attacking proteins, fragmenting DNA, and damaging mitochondria |
free radical | electrically uncharged atom or group of atoms that has an unpaired electron. To stabilize, they give up or steal an electron. When the attacked molecule loses its electron, it becomes a free radical. Hard to control |
antioxidants | SOD, glutathione peroxidase, catalase, vitamin E. ROS overwhelm them |
chemical injury | biochemical interaction between toxic substance and the cell's plasma membrane(leads to increased permeability); CCl4, lead, CO, ethanol, mercury, drugs |
lead | a heavy metal in the environment, hazardous mostly for children and pregnant mothers; affects nervous system, hematopoietic system, and kidneys. |
effects of lead | Alters calcium, interferes neurotransmitters, inhibits enzymes involved in hemoglobin synthesis, causes anemia, convulsions, delirium, paralysis, nausea, weight loss, etc |
carbon monoxide | odorless, colorless, undetectable gas produced by incomplete combustion of fuels. Produces hypoxic injury- affinity for hemoglobin is higher than oxygen so oxygen cant bind |
ethanol | causes nutritional disorders and liver injury |
4 Unintentional and Intentional Injuries | blunt force injuries, sharp force injuries, gunshot wounds, asphyxial injuries |
blunt force injuries | application of mechanical energy to the body resulting in the tearing, shearing, or crushing of tissues |
contusion | bruise; bleeding into skin or underlying tissues as a result of a blow that squeezes or crushes the soft tissues and ruptures blood vessels without breaking the skin. Color changes (red/purple->blue/black-> yellow/green/brow) reflect healing process |
hematoma | collection of blood in soft tissue or an enclosed space |
subdural hematoma | collection of blood between inner surface of dura mater and brain resulting in shearing of small veins that bridge the subdural space |
epidural hematoma | collection of blood between inner surface of the skull and the dura. Caused by a torn artery |
abrasion | scrape; results from removal of the superficial layers of skin that was caused by friction between skin and injuring object |
laceration | tear or rip resulting when the tensile strength of the skin or tissue is exceeded. Jagged or irregular |
avulsion | wide area of tissue pulled away, creating a large skin flap |
sharp force injuries | cutting and piercing injuries |
incised wound | cut that is longer than it is deep. sharp, distinct edges without abrasion |
stab wounds | a penetrating sharp force injury that is deeper than it is long; depths of wound are clean and distinct, no underlying or associated crush injury; a lot of internal bleeding |
puncture wounds | caused by instruments or objects with sharp points but without sharp edges |
chopping wounds | combo of sharp and blunt force; axes, hatchets, etc |
gunshot wounds | can be penetrating(bullet retained in body) or perforating(bullet exits) |
contact range entrance wounds | occur when gun is held so the muzzle rests on or presses into the skin surface |
blowback | occur in hard contact wounds of the head; gas and explosive energy sent into wound causes severe tearing and disruption of tissues, giving the wound a large, gaping and jagged appearance |
muzzle imprint | patterned abrasion that mirrors the features of the weapon |
intermediate range entrance wound | surrounded by gunpowder tattooing or stippling |
indeterminate range entrance wound | occurs when the only thing striking the body is the bullet |
exit wounds | shape can be round or slit like to completely irregular |
ashpyxial injuries | caused by failure of cells to receive or use oxygen |
suffocation | oxygen failing to reach the blood; results from lack of oxygen in environment or blockage of airways. Includes choking asphyxiation- obstruction of internal airways |
strangulation | caused by compression and closure of the blood vessels and air passages resulting from external pressure on the neck; results in stop of blood flow to brain; hanging, ligature, manual strangulation |
chemical asphyxiants | cyanide and hydrogen sulfide |
drowning | alteration of oxygen delivery to tissues resulting from breathing of fluid/water. |
dry lung drowning | in as many as 15% of drownings, little or no water enters lungs because of vagal nerve mediated laryngospasms |
Infectious injury | when a microorganism has disease producing potential(can invade and destroy cells, produce toxins and produce hypersensitivity reactions) |
Immunologic and Inflammatory Injury | cellular membranes are injured by direct contact with cellular and chemical components of the immune and inflammatory responses |
complement | responsible for many of membrane alterations that occur during immunologic injury (causes leakage of K+ out of cell and rapid influx of water) |
cellular accumulations(infiltrations) | occur in normal and injured cells;WATER, lipids, carbs, glycogen, proteins, etc |
cellular swelling | most common degenerative change;caused by shift of extracellular water into cells.(Hypoxia-> decreased ATP->Na and water move into cell and K diffuses out-> increased osmotic pressure->more water moves into cell->vacuolation->ONCOSIS/VACUOLAR DEGENERATION |
hemosiderin | yellow brown pigment derived from hemoglobin. How iron is stored in tissue cells when iron levels are high. |
hemosiderin accumulation | accumulates in areas of bruising and hemorrhage and in lungs and spleen after congestion from heart failure. Skin appears red-blue and then lysis of escaped rbcs occurs, causing hemoglobin to be transformed to hemosiderin |
calcium accumulation | causes cellular calcification- influx of extracellular calcium in injured mitochondria. Also can be caused by excretion of acid which leads to OH- ions which leads to precipitation of calcium hydroxide and hydroxyapatite |
dystrophic calcification | occurs in dying and dead tissue |
metastatic calcification | consists of mineral deposits that occur in undamaged normal tissues as a result of hypercalcemia |
necrosis | cellular death leading to cellular dissolution; the sum of cellular changes after local cell death and the process of cellular self digestion |
autolysis | process of cellular self digestion known as autodigestion |
karyolyisis | nuclear dissolution and chromatin lysis |
pyknosis | nucleus shrinks and becomes a small dense mass of genetic material |
karyorrhexis | fragmentation of the nucleus into smaller particles or "nuclear dust" |
4 major types of necrosis + 2 other types | coagulative, liquefactive, caseous, fatty, gangrenous,gas gangrene |
coagulative necrosis | occurs in kidneys, heart, and adrenal glands; commonly results from hypoxia caused by ischemia or chemical injury,; caused by PROTEIN DENATURATION |
liquefactive necrosis | commonly results from ischemic injury to neurons and glial cells in the brain. Brain cells are rich in digestive hydrolytic enzymes and lipids. The cells are digested by their own hydrolases. Tissue becomes soft, liquefies, walled off from healthy tissue. |
caseous necrosis | usually results from tuberculosis pulmonary infection. Combination of coagulative and liquefactive necroses. Tissues resemble clumped cheese |
fat necrosis | cellular dissolution caused by lipases that occur in the breast, pancreas, and abdominal organs. Necrotic tissue appears opaque and chalk white |
lipase | break down triglycerides, releasing free fatty acids, which combine with calcium, magnesium and sodium ions, creating soaps(saponification) |
gangrenous necrosis | death of tissue from sever hypoxic injury (b/c of arteriosclerosis, blockage of arteries) usually in lower leg |
dry gangrene | usually the result of coagulative necrosis. skin becomes dry and shrinks, color changes to dark brown or black |
wet gangrene | develops when neutrophils invade site, causing liquefactive necrosis. Ususally occurs in internal organs. Site becomes cold, swollen, black, foul odor, |
gas gangrene | special type of gangrene caused by infection of injured tissue by Clostridium sp. Death caused by shock |
Clostridium | anaerobic bacteria that produce hydrolytic enzymes and toxins that destroy connective tissue and cellular membranes and cause bubbles of gas to form in muscle soft tissue. |
apoptosis | "dropping off"; programmed cellular death. Affects scattered, single cells |
physiologic apoptosis | important in development of body tissue |
pathologic apoptosis | result of intracellular events or adverse exogenous stimuli (example: viral hepatitis induces apoptosis). Includes increase in apoptosis or the absence of apoptosis(leads to proliferation/accumulation of cells) |
characteristics of cellular aging | atrophy, decreased function, loss of cells, . |
tissue and systemic aging | progressive stiffness and rigidity, sarcopenia(loss of skeletal muscle mass and strength) |
frailty | mobility, balance, muscle strength, motor activity, cognition, nutrition, endurance, falls, fractures, bone density |
somatic death | death of an entire person. followed by postmortem changes |
algor mortis | postmortem reduction of body temperature |
livor mortis | pooling of blood in most dependent/lowest tissues which develop a purple discoloration |
rigor mortis | without ATP, detachment of myosin from actin is compromised and the muscles remain in a contracted position |
postmortem autolysis | release of enzymes and lytic dissolution |
total body water | the sum of fluids within all body compartments |
intracellular fluid | all the fluid within cells (2/3 of TBW and 40% of body weight) |
extracellular fluid | all the fluid outside the cells; interstitial fluid and intravascular fluid (1/3 of TBW and 20% of body weight) |
interstitial fluid | between cells an outside blood vessels(15% of body weight) |
intravascular fluid | blood plasma(5% of body weight) |
effect on aging to TBW | elderly have less TBW because of increase adipose tissue/decrease muscle mass, renal decline results in less retention of water and diminished thirst perception leads to dehydration |
antidiuretic hormone | secreted by the posterior pituitary gland in response to increased osmolality, decreased blood volume, or decreased blood pressure. Increases water retention by the kidney |
osmoreceptors | stimulated by hyperosmolality. Stimulate thirst and signals posterior pituitary to release ADH |
baroreceptors | nerve endings that are sensitive to changes in volume and pressure. When there is a decrease in blood volume and blood pressure, they stimulate ADH |
Sodium | accounts for 90% of the ECF cations. Regulates extracellular osmotic forces and regulates water balance |
Chloride | the major anion in the ECF and provides electroneutrality in relation to sodium. Passive transport following active transport of sodium. Maintains acidity of gastric secretions |
aldosterone | a mineralocorticoid secreted form the adrenal cortex that increases the reabsorption of sodium and the secretion of potassium. |
RAA Mechanism(Renin Angiotensin Aldosterone) | When blood volume and bp are reduced Renin is secreted by kidney, combines with angiotensinogen to make Angiotensin I. Angiotensin I is converted to Angiotensin II in the lungs by ACE. Angiotensin II stimulates vasoconstriction and stimulates aldosterone |
Atrial Natriuretic Factor | functions in renal elimination of sodium to control sodium and water balance. Blocks the effects of aldosterone. Also reduces blood pressure. |
Hypovolemia | fluid volume deficit; fluid loss, reduced fluid intake, fluid shift out of vascular space(3rd spacing). Caused by hemmorhage, polyuria, vomiting, diarrhea, fistulas, fever, nasogastric suctioning, etc |
1 L of water lost is equal to ??? lbs | 2.2 lbs is equal to ??? L of water lost |
detecting dehydration | thirst, poor skin turgor, dry mucous membranes, tachycardia, weak pulse, postural hypotension. shock, decreased urinary output, elevated hematocrit and serum sodium, skin tenting, |
electrolytes | substances whose molecules dissociate into ions when placed in water |
simple diffusion | movement of molecules from areas of high concentration to areas of low concentration; requires no external energy. |
facilitated diffusion | movement of molecules from areas of high concentration to low concentration; combine with a carrier molecule. Passive(requires no external energy) |
active transport | passage of ions or molecules across a cell membrane by an energy consuming pricess ; takes place against an electrochemical gradient(low-->high). Example: sodium potassium pump |
osmosis | movement of fluid through a semipermeable membrane; from area of low solute concentration to area of higher solute concentration until equilibrium is reached. Requires no external energy. Stops when conc. differences disappear or hydrostatic pressure inc. |
osmolality | osmotic force of solute per unit weight of solvent (describes fluids inside the body) |
osmolarity | total milliosmoles of solute per unit of total volume of solution (describes fluids outside of the body) |
isotonic/iso-osmolar solutions | have same osmotic pressure as blood (same amount of solutes); Normal Saline (0.9%), Lactated Ringers Solution, 5% dextrose in water(D5W). |
hypotonic/hypo-osmolar solution | lower osmotic pressure than blood/fewer solutes; 1/2 normal saline(.45% NaCl) or 2.5% dextrose in water (D2.5W)--> fluid moves into cell to compensate |
hypertonic/hyper-osmolar solution | higher osmotic pressure than blood/more solutes; hypertonic saline (>5% NaCl), 5% dextrose in NS(D5NS) or 5% dextrose in lactated Ringers solution (D5LR).-->fluid moves out of cell to compensate |
hydrostatic pressure | force within a fluid compartment that pushes water out. "pushes" |
oncotic pressure (colloidal osmotic pressure) | osmotic pressure from colloids in solution. Wants to keep water inside. "pulls" |
What pushes water out of capillaries? | capillary hydrostatic pressure and interstitial oncotic pressure |
What pulls water into capillaries? | plasma oncotic pressure and interstitial hydrostatic pressure |
filtration | movement of water and solutes by forces of pressure |
forces favoring filtration | capillary hydrostatic pressure and interstitial oncotic pressure |
forces favoring reabsorption | plasma oncotic pressure and interstitial hydrostatic pressure |
edema | accumulation of fluid in the interstitial spaces. Caused by an increase in plasma hydrostatic pressure, lowering of plasma oncotic pressure, increased capillary membrane permeability, and lymphatic channel obstruction. |
symptoms of edema | weight gain, swelling, puffiness, limited movement of affected joints, pitting of skin when pressed, |
second spacing | abnormal accumulation of interstitial fluid (edema) |
third spacing | fluid accumulation trapped and unavailable for functional use (ascites and edema associated with burns) |
ascites | accumulation of fluid in the peritoneal space |
hypothalamus | contains osmoreceptors that sense increases in plasma osmolality. Stimulates thirst and ADH release (ADH is syntehsized here) |
Pituitary region | releases ADH in response to increased plasma osmolality, decrease in blood volume, stress, nausea, nicotine, morphine |
Syndrome of Inappropriate Antidiuretic Hormone Secretion | occurs when factors other than hyperosmolality or hypovolemia stimulate secretion of ADH. Causes water to be retained in excess (decrease renal excretion of water) |
Renal Regulation (function of kidneys) | primary organ for regulating fluid and electrolytes, ADH and aldosterone work on its tubules, impairment causes edema, potassium and phosphorus retention, acidosis |
ways of losing water | vaporization from lungs and skin, increased body temp/exercise, excessive sweating |
hypovolemia | fluid volume deficit; fluid loss, reduced fluid intake, fluid shift out of vascular space(3rd spacing). Caused by hemmorhage, polyuria, vomiting, diarrhea, fistulas, fever, nasogastric suctioning |
clinical manifestations of hypovolemia | restlessness, drowsiness, lethargy, confusion, thirst, dry mouth, decreased skin turgor, dizziness, postural hypotension, weakness, weight loss, increased respiratory rate, seizures, coma, etc |
hypervolemia | fluid volume excess; caused by excessive isotonic/hypotonic IV fluids, renal/heart failure, polydipsia, SIADH, etc. |
clinical manifestations of hypervolemia | headache, confusion, lethargy, peripheral edema, distended neck veins, bounding pulse, increased BP and CVP, polyuria, muscle spasms, weight gain, seizures, coma |
osmotic pressure | pressure needed to oppose the movement of water across the membrane |
Hypernatremia | excess of serum sodium; caused by a loss of water or a gain in sodium intake. Leads to cellular dehydration. |
Causes of hypernatremia | deficiency in synthesis/release of ADH, decrease in kidney response to ADH, primary aldosteronism, too rapid infusion of hypertonic saline, sodium bicarb, or isotonic saline, drinking salt water, high salt intake, diarrhea, diabetes insipidus, dehydration |
clinical manifestations of hypernatremia | intracellular dehydration, convulsions, pulmonary edema, hypotension, tachycardia, etc. Thirst, fever, dry mucous membranes, restlessness |
Treating Acute Hypernatremia | if it occurs in a period of 48 hours or less, correct it rapidly |
Treating chronic hypernatremia | corrected more slowly due to risks of brain edema( if extracellular tonicity is decreased to quickly, water will move into brain cells) |
Hyponatremia | deficit of serum sodium; cause plasma hypo-osmolalty and cellular swelling |
Dilutional Hyponatremia | occur when proportion of TBW to total body sodium is excessive |
Hypo-osmolar Hyponatremia | When renal excretion of water is impaired and TBW and sodium are increased, but the retention of water exceeds increase in sodium |
Hypertonic Hyponatremia | increases in plasma lipids and proteins displace water volume and decrease sodium concentration(hyperglycemia attracts ICF and increase in ECF dilutes concentration of sodium) |
clinical manifestatins of hyponatremia | decreased osmolality, free water excess, ECF goes into cells and causes hypovolemia, free water excess can also cause hypervolemia/water intoxication; lethargy, confusion, decreased reflexes, seizures, coma |
causes of hyponatremia | excessive diuresis, excessive sweating, GI loss, adrenocortical insufficiency, excess IV fluids, SIADH |
Hyperchloremia | excess of chloride, occurs with hypernatremia or deficit in bicarbonate. Manifestations include metabolic acidosis, stupor, deep rapid respirations, weakness, coma |
hypochloremia | deficit in serum chloride, result of hyponatremia or elevated bicarbonate. Develops as a result of vomiting and loss of HCL. Manifestations include metabolic alkalosis, muscle hypertonicity, depressed respirations, tetany |
potassium | major intracellular cation. regulates intracellular osmolality, excreted by kidneys, concentration maintained by Na+/K+ pump, regulate intracellular electrical neutrality, essential for action potentials, normal cardiac rhythm, muscle contraction |
things that affect potassium levels | changes in pH(H+ ions accumulate in ICF during acidosis. K+ shifts out to balance), aldosterone, insulin, epinephrine, alkalosis(all make K+ move into cells) |
hyperkalemia | elevation of ECF potassium above 5.5 mEq/L. |
causes of hyperkalemia | increased intake of K+, shift of K+ from the ICF to the ECF, decreased renal secretion, insulin deficiency, or cell trauma |
ECG changes with hyperkalemia | tall peaked T wave, wide QRS complex, ventricular fibrillation, cardiac arrest |
clinical manifestations of hyperkalemia | mild: neuromuscular irritability; severe:cell cant repolarize, muscle weakness, loss of muscle tone, flaccid paralysis |
hypokalemia | decrease in the ECF potassium concentration below 3.5 mEq/L. |
causes of hypokalemia | reduced intake of potassium, increased intracellular entry of potassium, increased loss of potassium, alcoholism, alkalosis, DIURETICS/ PROLONGED VOMITING/DIARRHEA, aldosterone, laxative abuse, etc.--> K+ shifts from ECF to ICF |
ECG changes with hypokalemia | flattened T wave, prolonged PR interval, large U wave |
clinical manifestations of hypokalemia | decrease in neuromuscular excitability, skeletal muscle weakness, smooth muscle atony, and cardiac dysrhythmias |
calcium | essential cation, widely distributed, 99% is found in bone as hydroxyapatite, necessary for bone, clotting, hormone secretions, neuromuscular function, muscle contraction, maintenance of membrane permeability |
parathyroid hormone | released by low serum Ca2+ (raises Calcium levels in blood--> stimulates bone to release Ca). Also helps excrete phosphate. |
calcitonin | stimulated by high serum Ca2+(lower calcium levels in blood--> stimulates take up of Ca by bones) |
vitamin D | reabsorbs Ca2+ from GI tract |
hypercalcemia | excess of serum calcium. Increases the block of Na+ into cell |
causes of hypercalcemia | hyperparathyroidism, cancer, vitamin D overdose, hypophosphatemia, thyrotoxicosis, acromegaly, renal failure |
clinical manifestations of hypercalcemia | decreased neuromuscular excitability, muscle weakness, cardiac arrest, constipation, kidney stones, anorexia, nausea, vomiting, decrease in heart rate, confusion |
hypocalcemia | deficit of serum calcium. Decreases block of Na+ into cell |
causes of hypocalcemia | hypoparathyroidism, hyperphosphatemia, vitamin D deficiency, hypoalbuminemia |
manifestations of hypocalcemia | numbness, muscle crams, increased neuromuscular excitability, weakness, hypotension, Chvostek and Trousseaus signs, tetany, seizures, emotional instability, etc |
chvostek's sign | contraction of facial muscles in response to light tap over the facial nerve in front of ear |
trousseau's sign | carpal spasm induced by inflating a blood pressure cuff above systolic pressure for a few minutes |
Calcium's relationship to Phosphate | inverse relationship; if concentration of one increases, the other decreases |
phosphate | major intracellular anion, essential to muscle function, RBCs, and nervous system; most is located in bone. Needed for ATP. |
pH | the inverse logarithm of the H+ concentration; ranges from 0-14. H+ high means low pH(acidic) and H+ low means high pH(basic) |
3 organs involved in regulation of acid base balance | bones, lungs, kidneys |
pH of blood | 7.35-7.45 |
functions of acids | byproducts of energy metabolism(carbonic acid, lactic acid), digestion(HCl), food for brain(ketoacids) |
volatile acid | carbonic acid (H2CO3); can be eliminated as CO2 |
nonvolatile acid | lactic acid, sulfuric, phosphoric acids; eliminated through kidneys |
An increase in CO2 will cause: | increase in CO2, increase in H+, increase in bicarbonate |
buffer | absorb excessive hydrogen (H+) or hydroxyl (OH-) and prevent significnant change in pH. |
important buffering systems | carbonic acid- bicarbonate system and hemoglobin |
carbonic acid bicarbonate buffer system | CO2+H2O<-->H2CO3<-->H+ + HCO3- . The greater the partial pressure of carbon dioxide, the more carbonic acid is formed. |
respiratory acidosis | increased pCO2, increased carbonic acid, increased H+(low pH), increased bicarbonate. Result of ventilation depression |
respiratory alkalosis | decreased pCO2, decreased carbonic acid, decreased H+(high pH), decreased bicarbonate. Result of hyperventilation |
metabolic acidosis | increased levels of ketoacids, lactic acid. Decreased bicarbonate levels, increased H+(low pH)--> heavier breathing causes decreased pCO2 |
metabolic alkalosis | decreased H+ levels, increased bicarbonate levels--> lighter breathing causes increased pCO2 |
compensations | renal and respiratory adjustments to changes in pH . (Production of acidic or alkaline urine, or change in ventilation) |
protein buffering | proteins have negative charges, so they can serve as buffers for H+ |
renal buffering | secretion of H+ in the urine and reabsorption of HCO3- |
cellular ion exchange | exchange of K+ for H+ in acidosis and alkalosis |
anion gap | the difference between the plasma concentration of major cation (Na+) and sum of measured anions (Cl- and HCO3-). Represents concentration of unmeasured anions. Na- (Cl+HCO3-). Normal is 8-12. Increased in lactic acidosis, ketoacidosis |
Abnormal anion gap (indications) | abnormal anion gap is a result of an increased level of an abnormal unmeasured anion. Examples: diabetic ketoacidosis, lactic acidosis |
Respiratory System as regulator of acid base balance | eliminates CO2, medulla controls breathing. Increased respirations lead to decreased CO2(hyperventilations). |
Renal System as a regulator of acid base balance | eliminates H+ and reabsorbs HCO3-. Also reabsorbs/secretes electrolytes. Kidneys decrease/increase urine pH |
Respiratory Acid base Imbalances | affect carbonic acid concentration (CO2) |
metabolic acid base imbalances | affect bicarbonate |
Respiratory Acidosis Causes | hypoventilation(slow breathing gives a carbonic acid/CO2 excess), respiratory failure(raises CO2) |
Respiratory Acidosis Compensation | kidneys conserve HCO3- and secrete H+ into urine(metabolic alkalosis) |
Respiratory Alkalosis Causes | hyperventilation(causes deficit in carbonic acid/CO2), hypoxemia from acute pulmonary disorders |
Respiratory Alkalosis Compensation | rarely occurs due to aggressive treatment of causes of hypoxemia. |
Metabolic Acidosis Causes | bicarbonate deficit caused by ketoacidosis, lactic acid accumulation, severe diarrhea, kidney disease |
Metabolic Acidosis Compensation | increased CO2 excretion by lungs (respiratory alkalosis) |
Metabolic Alkalosis Causes | bicarbonate excess caused by prolonged vomiting and gain of HCO3- |
Metabolic Alkalosis Compensation | decreased respiratory rate to increase CO2, renal excretion of HCO3-(respiratory acidosis) |
main sign of dehydration | weight loss (1 L=1 kg=2.2 lbs) |
Diagnostic criteria for dehydration | a BUN/creatine ratio of >25:1,OR orthostasis, OR a pulse of >100 beats/minute, OR a pulse change of 10-20 beats/minabove baseline with a change in position |
orthostasis | drop in systolic BP >20 mmHg upon a change of position |
Hypertonic Dehydration | primarily fluid deficit; more water than salt is being lost |
Hypotonic Dehydration | primarily sodium deficit; more salt than water is being lost |
isotonic Dehydration | combined water and sodium deficit; both salt and water are lost proportionately |
formula for fluid replacement therapy in hypernatremia | calculate free water deficit: .6 x body weight(kg) x [(plasma Na/140) -1] OR Change in serum sodium= (infusate sodium-serum sodium)/(TBW+1) |
electrolytes lab tests | usually provides info about serum Na, K, Cl, HCO3- |
BUN and Cr lab tests | indication of renal perfusion; elevated BUN reflects intravascular depletion; Cr indicates acute renal failure |
CBC lab test | info on hemoconcentration secondary to dehydration; WBCs and differential indicators of infection; platelets can elevate as acute phase reactants |
UA lab test | specific gravity of urine related to hydration state; in renal disease, can help classify condition; urine ions aid in determining if Na is being retained or not |
total protein lab test | indirect measures of live function, dietary protein intake, and renal loss. |
arterial blood gas test | aids in classification of acidosis and alkalosis. Give info on bicarbonate levels |
Interpretation of ABGs (5 steps) | 1) evaluate pH (tells you if its alkalosis or acidosis). 2) Analyze pCO2. 3) Analyze HCO3-. 4) Determine if CO2 or HCO3- matches the pH alteration (respiratory vs. metabolic). 5) Decide if the body is trying to compensate (is pH normal or not?) |
ROME | Respiratory Opposite= up pH down CO2(alkalosis) and down pH up CO2(acidosis). Metabolic equal= up pH up CO2 (alkalosis) and down pH down CO2(acidosis) |
partial compensation | after HOURS of acid bas imbalance, the lungs or kidneys will try to bring pH back to normal. ALL parameters will be outside of normal range |
full compensation | after days or months of untreated acid base imbalance, the pH will be back to normal range, but all other parameters will be abnormal |
acidemia | more acidic than normal (pH is acidic compared to normal pH of 7.4 but pH still doesnt tell us if it is a respiratory or a metabolic problem) |
bicarbonate levels as an indicator for acid base imbalance | bicarbonate levels measure metabolic acidosis when a patient has no respiratory abnormality |
alkalemia | more basic than normal (when the pH rises above 7.45) |