Unit 10 Review Flashcards
2/3rds of body’s H2O is in …
intracellular fluid
electrolyte most prevalent inside of cells
K+ (also Ca++, Mg++, PO4)
4 physiologic mechanisms that contribute to edema formation
- increased capillary hydrostatic pressure
- decreased plasma oncotic pressure
- increased capillary membrane permiability
- lymphatic obstruction
the ________ pressure between _____________ and _____________ compartments is trying to stay in ____________
osmotic
extracellular
intracellular
equilibrium
fluid shifts between intracellular and extracellular compartments r/t osmotic pressure changes cause…
third-spacing
lots of Na+ transported into cell, osmotic pressure in cell increases or decreases?
increases
When Na+ increases in cell, what happens to H2O?
it follows Na+ into cell to balance osmotic pressure and cell swells
abnormal accumulation of fluid in extracellular compartment can be caused by:
hypoproteinemia
lyphatic obstruction
increased venous pressure
increased capillary permeability
the ECF volume is divided between the _________ and the ____________ fluid compartments
vascular
interstitial
the ICF volume is regulated by ____________ and organic compounds in the ICF and by ____________ that move freely between the ICF and ECF
proteins
solutes
the transfer of H2O between the vascular and interstitial compartments happens at what level?
cellular
excessive accumulation of fluid within the interstitial spaces
edema
edema is a problem of __________ _______________ and does not necessarily indicate a __________ _________.
fluid distribution
fluid excess
reasons for increased capillary hydrostatic pressure
venous obstruction salt or water retention thrombophlebitis hepatic obstruction tight clothing around extremities prolonged standing CHF renal failure cirrhosis
reasons for decreased plasma oncotic pressure
liver disease protein malnutrition glomerular disease serous drainage from open wounds hemorrhage burns cirrhosis
reasons for increased capillary membrane permiability
inflammation or immune response trauma burns crush injuries neoplastic diseases allergic reactions
reasons for lymphatic obstructions
infection
tumor
proteins and fluid accumulating in interstitial spaces
lymphedema
the effects of edema are determined largely by _________
location
edema to brain, larynx, or lungs would be considered
an acute life-threatening condition
treatment of edema…
treat underlying cause reduce Na+ diuretics compression stockings elevate legs
what is the most abundant cation in the body
Ca++
positive ions
cations
Ca++ ions combine with _____________ ______ to for ___________ _____________ which increases the rigidity and hardness of bones and teeth enamel
phosphate ions
calcium phosphate
how does Na+ enter the body
consumed in food, drink, medications, etc…
How does Na+ leave the body
urine, sweat, tears, primarily
which organ is the main regulator of Na+?
kidneys (adrenals are 2nd to kidneys)
total body water varies with __________ and _________ and these differences can be explained by differences in body __________________
gender
weight
composition
what are two main physiologic mechanisms that assist in regulating body water?
urination and sweating
where is anti-diuretic hormone produced?
hypothalamus and secreted by pituitary
how does ADH exert its influence in the reabsorption of water
ADH acts on the vasopressin 2 receptors in the renal tubular cells to increase permiability which leads to an increase in H2O absorption into the bloodstreams and the production of more concentrated urine
insufficiency of ADH resulting in polyurea and polydipsea
Diabetes insipidus
two forms of DI
neurogenic and nephrogenic
What is the most common form of DI?
neurogenic diabetes insipidus
Neurogenic DI results when any lesion on the _____________, ____________ _________, or _________ _________ interferes with the ADH _______, _________, or __________.
hypothalamus pituitary stalk posterior pituitary synthesis transport release
insensitivity of the renal collecting tubules to ADH
nephrogenic diabetes insipidus
6 causes of hyponatremia
- inadequate intake of Na+
- diuretics
- vomiting, diarrhea, GI suctioning
- burns
- renal failure
- SIADH
inadequate H2O intake, too much hypertonic saline solution & oversecretion of aldosterone cause
hypernatremia
other causes of hypernatremia
Cushings Syndrome excessive H2O loss impaired thirst water loss due to fever or respiratory infxn DI or DM high amounts of sodium in diet (rare)
what is the major cation in the ICF
K+
10 causes of hypokalemia
ETOH, anorexia, alkalosis, tx of pernicious anemia with B12, genetic, laxative abuse, diarrhrea, intestinal drainage tubes, vomiting, NG tubes, diuretics, excessive aldosterone drainage from adrenal adenoma, antibiotics
treatment for hypokalemia
K+ replacement
40-80 meq/day
causes of hyperkalemia
metabolic acidosis
decreased kidney function
insulin deficiency, hyperglycemia, hyperosmolality
blood transfusion
divalent cations
Ca++, Phos, and Mag
cation missing two electrons compared to a neutral cation
divalent
positively charged ion with two electrons in outer shell
cation
three manifestations of hypoparathyroidism
muscle spasms
chvostek sign: tap on cheek & the upper lip twitches
Trousseau sign: painful carpal spasm after prolonged inflation of BP cuff
low phosphate
where is parathyroid hormone produced
parathyroid gland
where does parathyroid hormone exert influence
acts on kidneys and bones
regulates serum Ca++
describe action of parathyroid hormone
in kidneys PTH increases Ca++ absorption, decreases phos and bicarb reabsorption,
also stimulates synthesis of biologically active Vit D
(1,25-dihydroxy vitamin D3)
in the bones, PTH mobilizes Ca++ from bones during times of hypCa++
importance of ionized Ca++
free, active form can move from ECF to ICF in muscle contraction
s/sx of hypCa++
tetany
important fxns of Ca++
necessary for metabolic processes
major cation for structure of bone and teeth
enzymatic cofactor for blood clotting
transmission of nerve impulses and contraction of muscles
required for hormone secretion
plasma membrane stability and permeability
can cause partial depolarization of nerves and muscles
hypoCa++
s/sx of partial depolarization of nerves and muscles
confusion, paresthesias around mouth, carpopedal spasm, hyperreflexia, convultions and tetany,
continuous muscle spasm can interfere with breathing & cause death
tetany
provides the form of ATP for energy and acts as intra and extracellular buffer in the regulation of acid-base balance
phosphate
what happens with hypophasphatemia
reduced capacity for O2 transport by RBCs
disturbed energy metabolism
decreased release of O2 to tissues causing hypoxia, bradycardia, and heart block
common cause of hypophosphatemia
intestinal malabsorption and increased renal excretion of phosphate vit D deficiency use of antacids ETOH abuse (chronic) respiratory alkalosis
which organ is the principal organ of magnesium regulation
kidneys (also small intestine)
cardiovascular manifestations of hypermagnesemia
depress muscle contraction & nerve function
hypotension
bradycardia
N/V, muscle weakness, respiratory depression
volatile acide
carbonic acid (in the lungs)
three ways pH is regulated
short term (w/in seconds) - buffers in blood medium (w/in minutes) - lungs or rate/depth of respiration long term (hours to days) - kidneys - bicarb - uptake and excretion
largest buffer systems in body
intracellular buffers (inside cells)
extracellular buffers (blood, ISF, CSF, urine)
respiratory (lungs)
renal (kidneys)
increase in noncarbonic acids or loss of bicarbonate from extracellular fluid
metabolic acidosis
increase in bicarbonate usually caused by loss of metabolic acids from conditions like vomiting, diarrhea, GI suctioning, excessive bicarb intake,
metabolic alkalosis
decrease of alveolar ventilation and increase in levels of CO2 which causes hypercapnea
respiratory acidosis
occurs with hyperventilation and excessive reduction of CO2 or hypocapnia
respiratory alkalosis
two common types of metabolic acidosis
lactic acidosis - from poor perfusion, hypoxemia, CA, over exercising, liver failure, hypoglycemia, ETOH, meds like ASA diabetic acidosis (DKA) - build up of ketone bodies
untreated of uncontrolled Type I DM - increased ketones in blood,
DKA
formed during breakdown of fatty acids in order to transform them into energy
ketones
DKA is caused by several factors, the most common are:
infection, illness, skipping insulin therapy, trauma, stress, drug abuse, ETOH abuse
causes of respiratory acidosis
brainstem trauma, over sedation, respiratory muscle paralysis, kyposcoliosis, flail chest, pneumonitis, pulmonary edema, emphysema, asthma, bronchitis
common cause of respiratory alkalosis
hyperventilation (other causes: anxiety, fever, any lung disease that prompts hyperventilation)
