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135 Cards in this Set

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diffusion
particles move from higher concentration to lower concentration. Smoke. Particles are in constant motion, providing energy for diffusion.
osmosis
movement of water across a semipermiable membrane
osmotic pressue
the pressure to oppose osmosis
tonicity
the tension or effect that the effective osmotic pressure of a solution with impermeable solutes exerts on a cell size because of water movement across the cell membrane.
Isotonic
Hypotonic
hypertonic
nothing (maintainance)
swell (dehydration)
shrink (swelling-cerebral edema)
edema
palpable swelling produced by expansion of interstitial fluid volume
effects of edema
interfere with movement by limiting joint motion
increases the distance for oxygen, nutrients and waste.
3rd space accumulations
when fluids accumulate in the transcellular space, such as the pericardial sac, the pleural sac, or peritoneal cavity.
where are 3rd space locations
serous cavity, pericardial sac, peritoneal cavity (ascites), and the pleural cavity.
Mechanisms in which sodium is gained or lost
fever-metabloci rate increases-greater demand for water

respiratory rate increases-additional loss of water vapor through the lungs.

Oral intake

gi absorption and IV fluids
What causes isotonic fluid volume deficit
when water and electrolytes are lost in isotonic proportions

Almost always caused by a loss of body fluids

often accompanied by a decrease in fluid intake

vomiting, diarreha, excessive sweating
Signs and symptoms of isotonic fluid volume deficit
thirst
water conservation by the kidney
loss of body weight
impaired temperature regulation
signs of reduced interstitial and vascular volume
postural hypotension
dehydration
sunken eyeballs
dry mucous membranes
isostonic fluid excess
Can be pathological or compensatory.

Increase in total body sodium that is accompanied by a proportionate increase in body water

Excessive sodium intake

Most commonly caused by a decrease in sodium and water elimination by the kidney
isotonic fluid excess manifestations
weight gain over short amount of time
edema
jugular vein distention
BUN and hematocrit decreased
edema-lungs
shortness of breath, difficulty breathing, respiratory crackles,
and productive cough
Who is most at risk for hyponatremia and why?
the elderly b/c they have a decrease in renal function

They have a more difficult time maintaining body fluid homestasis
hyponatremia
fluid volume excess. cells swell
HYPERNATREMIA
causes celullar dehydration (fluid volume deficit)
Causes of hypernatremia
net gain of sodium or net loss of water

defect in thirst or inability to drink water

rapid infusion of sodium with insufficient time for water ingestion
hyponatremia
Decrease in renal function
Difficulty to maintain body fluid homeostasis

Fluid Volume Excess

lethargy
headache
disorientation
confusion
motor weakness
seizure
coma
loss of appetite

muscle cramps
weakness
fatigue

GI: nausea vomiting abdominal cramps, diarrhea, anorexia
Dibetes Insipidus
Deficiency of or a decreased response to ADH.

Results in polyuria. Usu. balanced by excess thirst.

Hypernatria (fluid excreted leaving a higher concentration of sodium

dehydration
Syndrome of inappropriate ADH (SIADH)
too much ADH is released; negative feedback system fails. Results in marked water retention and dilutional hyponatremia
Manifestations of SIADH
stress or chronic conditions
dilutional hyponatremia (retaining too much fluid-lowers concentration of sodium

Urine output decreases
urine osmolality high

serum osmolality low

hematocrit and serum sodium decreases

BUN levels decrease
hypovolemia
when the effective circulating blood is compromised
Where is most of the body's sodium?
In the extra cellular fluid compartment
calcium is a
membrane stabilizer
What could you give a pt with hyperkalemia?
insulin
#1 issue with potassium problems
heart-conducting nerve/ muscular impulses
PTH regulation on serum calcium
1) Promotes the release of calcium from the bone
2) Increases the activation of Vitamin D
3) Stimulates calcium retention and phosphate elimination from the kidneys

DOES NOT INCREASE HUNGER FOR CALCIUM PRODUCTS
hypoparathyroidism can result in
hypocalcemia
If one goes up the other goes down---BUT, if there is never enough PTH the body will not function well and be low in calicum.
hyperparathyroidism can result in
hypercalcemia

Too much PTH causing a release of too much Ca+
fluids are in three major compartments, what are they?
intracellular, plasma, and interstitial
within a solution, positive and _________ must balance regardless of the number of ions present
negative
Major Postive ions
Na
K
Ca
MG
Major negative IOns
Cl
HCO3 (bicarbonate)
Phospahate ions (HPO4)
Sulfate SO4
functions of electrolytes
cofactors for enzymes
action potentials in neuron and muscle cells
secretion of hormones and neurotransmitters
muscle contraction
capillary hydrostatic (filtration) pressure (CHP)
pushes water out of the capillary and into the interstitial spaces
movement of water through capillary pores because of a mechanical force
A rise in the arterial or venous pressure idependent parts of the body.
Results from the weight of the water-hydrostatic pressure
Capillary Colloidal Osmotic Pressure
Pulls water back up into the capillary. The osmotic pressure generated by lasma proteins that are too large to pass through the pores of the capillary wall
o Because plasma proteins do not normally penetrate the capillary pores and because their concentration is greater in the plasma than in the interstitial fluids, it is the capillary colloidal osmotic pressure that pulls fluid back into the capillary
Interstitial hydrostatic pressure (THP)
Force of fluid in the interstitial spaces. The interstitial pressure is slightly negative, contributing to the outward movement of fluid from the capillary
Tissue cuboidal osmotic pressure (TCOP)
o Pulls water out of the capillary into the interstitial spaces
o Reflects the small amount of plasma proteins that normally escape into the interstitial spaces from the capillary
o Also pulls water out of the capillary into the tissue spaces
Increased Capillary Filtration Pressure:
o The movement of vascular fluid into the interstitial spaces increase
o Factors that increase capillary pressure:
 A decrease in the resistance to flow through precapillary sphincters
 An increase in venous pressure or resistance to outflow at the postcapillary sphincters
 Capillary distension caused by increased vascular volume
Causes-
Increased vascular volume, such as
 Heart failure
 Kidney disease
 Premenstrual sodium retention
 Pregnancy
 Environment
 Heat stress
Venous obstruction, such as
Liver disease with portal vein obstruction
Acute pulmonary edema
Venous thrombosis (thrombo phlebitis)
Decreased Capillary Colloidal Osmotic Pressure
o If there is a decrease, there are less Protein-pulling magnets tking fluid out of the capilaries.

This causes inadequate osmotic force

Increased loss of plasma proteins, such as
 Protein-losing kidney disease
 Extensive burns
Decreased production of plasma proteins, such as
 Liver disease
 Starvation
 Malnutrition
Increased Capillary Permeability:
o The capillary pores become enlarged or the integrity of the capillary wall is damaged, capillary permeability is increased
o Plasma proteins and other osmotically active particles leak into the interstitial spaces, increasing the tissue colloidal osmotic pressure and contributing to the accumulation of interstitial fluid
Causes-
 Inflammation
 Allergic reactions
 Malignancy
 Tissue injury and burns
Obstruction of Lymphatic Flow:
Obstruction of Lymphatic Flow:
o Osmotically active plasma proteins and other large particles that cannot be reabsorbed through the pores in the capillary membrane rely on the lymphatic system for movement back to the circulatory system
o Fluid in the interstitial spaces is not being returned to the circulatory system properly
Causes-
 Malignant obstruction of lymphatic structures
 Surgical removal of lymph nodes
Normally, sodium and water changes are equivalent. True or false?
True
The concentration of sodium controls the ECF osmolality, so changes in sodium are accompanied by proportionate changes in _____________
water volume
Who has more body water: men or women?
men
What does obesity do to total body water?
Reduces amount of body water
What age group has the highest total body water?
Infants, but premature infants are even greater
Identify the mechanisms by which water is gained and lost
 What happens with fever?
o Metabolic rate increases-greater demand for water
o Respiratory rate increases-additional loss of water vapor through the lungs
 What is the main source of water gain?
o Oral intake and metabolism of nutrients
 GI absorption and IV
 What organ is responsible for the largest water loss?
o Kidneys
 GI tract and sweating
 What is obligatory urine output? What is the volume?
o The urine production required to eliminate metabolic wastes
o 300-500mL/day
 What is insensible water loss?
o Evaporative water losses from the respiratory tract and skin-occur without a person’s awareness
Most of the body’s sodium is in the __________ compartment.
extra cellular fluid
Sodium regulates extracellular fluid volume through....
osmotic activity, involved in acid-base balance, and contributes to function of the nervous system and other excitable tissues.
How is sodium lost?
Kidneys-regulating sodium output
The physiological mechanisms that regulate sodium excretion/conservation
 Sympathetic Nervous System
o Responds to changes in arterial pressure and blood volume by adjusting the glomerular filtration rate and the rate at which sodium is filtered from the blood
o Regulates tubular reabsorption of sodium and renin release
 Renin-angiotensin-aldosterone System
o Angiotensisn II
 Acts directly on the renal tubules to increase sodium reabsorption
 Acts to constrict renal blood vessels, thereby decreasing the glomerular filtration rate and slowing renal blood flow so that less sodium is filtered and more is reabsorbed
 Regulator of aldosterone
o Aldosterone
 Acts at the level of the cortical collection tubules of the kidney to increase sodium reabsorption while increasing potassium elimination
What are the 2 stimuli for true thirst based on water need?
 Cellular dehydration caused by an increase in extracellular osmolarity
 A decrease in blood volume which may or may not be associated with a decrease in serum osmolality
Hypodipsia
is a decrease in the ability to sense thirst while polydipsia represents excessive thirst.
ADH levels are controlled by what?
 Extracellular volume and osmolaltiy
 Osmoreceptors in the hypothalamus sense changes in extracellular osmolality and stimulate production and release of ADH
What can cause an abnormal increase in ADH synthesis?
 Stress situations
 Sever pain
 Nausea
 Trauma
 Surgery
 Certain anesthetic agents
 Some narcotics (morphine)
Diabetes insipidus (DI):
a deficiency of or a decreased response to ADH. Results in excretion of large volume of urine. Usually balanced by excessive thirst.
Manifestions of Diabetes insipidous
 Complaints of polyuria and intense thirst
 Hypernatremia (fluid excreted, higher concentration of sodium)
 Dehydration
Syndrome of inappropriate ADH (SIADH):
too much ADH is released; negative feedback system fails. Results in marked water retention and dilutional hyponatremia.
What are some causes and manifestations of SIADH?
 Stress or chronic conditions
 Dilutional hyponatremia (retaining too much fluid-lower concentration of sodium)
 Urine output decreases
 Urine osmolality-high
 Serum osmolality-low

 Hematocrit and serum sodium decreases due to blood dilution
 BUN (Blood, Urea, and Nitrogen) levels decrease due to blood dilution
DISORDERS OF SODIUM AND WATER BALANCE
isotonic fluid volume deficit and isotonic fluid volume excess.
Isotonic Fluid Volume Deficit
What is meant by isotonic fluid volume deficit?
 Differentiates this type of fluid deficit in which there are proportionate losses in sodium and water from water deficit and the hypersmolar state associated with hypernatremia
Define hypovolemia.
 When the effective circulating blood volume is compromised
What are the usual causes of isotonic fluid volume deficit?
 When water and electrolytes are lost in isotonic proportions
 Almost always caused by a loss of body fluids
 Often accompanied by a decrease in fluid intake
Manifestations. What are the signs and symptoms of isotonic fluid volume deficit?
 Thirst
 Signs of water conservation by the kidney
 Loss of body weight
 Impaired temperature regulation
 Signs of reduced interstitial and vascular volume
 Postural hypotension (reduced blood volume)
 Dehydration
Isotonic Fluid Volume Excess can be caused by
 Increase in total body sodium that is accompanied by a proportionate increase in body water
 Excessive sodium intake
 Most commonly caused by a decrease in sodium and water elimination by the kidney
Manifestations of Isotonic Fluid Volume Excess. What are the signs and symptoms?
 Weight gain over a short amount of time
 Presence of edema
 As vascular volume increases the jugular veins become distended, pulse becomes full and bounding, central venous pressure is elevated
 BUN and hematocrit decreased as a result of the expanded plasma volume
 Edema-lungs
o Shortness of breath, complaints of difficult breathing, respiratory crackles, and productive cough
Which population is most at risk for hyponatremia and why?
 Elderly
o Decrease in renal function-causing the kidney to fall behind on conserving sodium
o Difficulty to maintain body fluid homeostasis due to environmental, drug-related, and disease associated stress
hyponatremia:
 The sodium in ECF becomes diluted as water moves out of cells in response to the osmotic effects of elevated blood glucose levels
 Water retention
 Loss of water and sodium-excess sweating
 When water is used to replace fluids lost in sweating-should use electrolytes
 Loss of sodium in gastrointestinal tracts
 Retention of water with dilution of sodium in normal ECF volume
 Edema associated disorders…heart failure, cirrhosis, nephritic syndrome, and advanced renal disease
Manifestations hyponatremia
 Muscle
o Muscle cramps
o Depression of deep tendon reflexes
o Weakness
o Fatigue
 (Heavy exercise and hot water)
 Central Nervous
o Lethargy
o Headache
o Disorientation
o Confusion
o Gross motor weakness
o Seizure (severe)
o Coma (severe)
 Gastrointestinal
o Nausea
o Vomiting
o Abdominal cramps
o Diarrhea
o Anorexia

Causes. List some causes of hypernatremia.
 Net gain of sodium or net loss of water
 Rapid ingestion or infusion of sodium with insufficient time or opportunity for water ingestion-disproportionate gain in sodium
 Defect in thirst or inability to obtain or drink water-can interfere with water replacement

Most likely to occur in what age groups?
 Infants and people who cannot express their thirst or obtain water to drink
Hypernatremia causes...
Results in hypertonicity of the ECF and causes cellular dehydration.
Hypernatremia Causes:
 Net gain of sodium or net loss of water
 Rapid ingestion or infusion of sodium with insufficient time or opportunity for water ingestion-disproportionate gain in sodium
 Defect in thirst or inability to obtain or drink water-can interfere with water replacement
Hypernatremia, Most likely to occur in what age groups?
Infants and people who cannot express their thirst or obtain water to drink
Manifestations hypernatremia
Mostly associated with dehydration. What are they?
 Increased thirst
 Increased ADH with oliguria and high urine-specific gravity
 Dry skin and mucous membranes
 Decreased tissue turgor
 Decreased salivation and lacrimation
 Headache
 Disorientation and agitation
 Decreased reflexes
 Seizures (severe)
 Coma (severe)
 Weak, rapid pulse
 Impaired temperature regulation with fever
 Decreased blood pressure
 Vascular collapse (severe)
Potassium Balance. 98% of the body’s potassium is which…..intracellular or extracellular?
intracellular
The body stores most of the potassium where?
muscles
Describe the physiologic mechanisms that regulate potassium.
RENAL REGULATION:
What does aldosterone do to potassium?
 In the presence of aldosterone, sodium is transported back into the blood
 Potassium is secreted into the tubular filtrate for elimination in the urine

How does the potassium-hydrogen exchange system work?
 When serum potassium levels are increased, potassium is secreted into the urine and hydrogen is reabsorbed into the blood, producing a decrease in pH and metabolic acidosis
 When potassium levels are low, potassium is reabsorbed and hydrogen is secreted into the urine, leading to metabolic alkalosis

Extracellular-Intracellular Shifts:
Metabolic acidosis >>> H+ ions move into cells >>> potassium leaves the cells.
Metabolic alkalosis >>> H+ ions leave the cells >>> potassium enters the cells.
Serum osmolality increases cause potassium to move out of cells into the ECF.
Repeated muscle exercises causes potassium to what?
To be released into the ECF
Potassium is a super important electrolyte that does what?
REGULATES ELECTRICAL MEMBRANE POTENTIALS (esp important for Cardiac, Skeletal, and smooth muscles)

 Maintenance of the osmotic integrity of cells
 Acid-Base balance
 Kidney’s ability to concentrate urine
 Necessary for growth
 Contributes to the chemical reaction that transforms carbohydrates into energy
 Changes glucose into glycogen
 Convert amino acid and proteins
Since hypokalemia (decreased potassium) moves the resting membrane potential (RMP) further from the threshold for excitation, it requires a ___________ stimulus to reach the threshold.
greater
Hyperkalemia (increased potassium) moves the RMP closer to the threshold causing an initial increase in membrane _____________
excitability
3 causes of Hypokalemia
 Inadequate intake
o Inability to obtain or ingest food
o Diet that is low in potassium-containing foods
 Excessive losses through the kidney, skin, or gastrointestinal tract
o Diuretic use
o Metabolic alkalosis
o Magnesium depletion
o Trauma and stress
o Increased levels of aldosterone
o Vomiting
o Loss of protective skin surface
o Sweating
o Burns
 Redistribution between the ICF and ECF compartments
o β2-adrenergic agonist drugs (decongestants)
o Insulin
K+ has a critical role in conducting nerve impulses and the excitability of skeletal, cardiac, and smooth muscle … how does it do this? Describe the 3 ways:
o Regulates Resting Membrane Potential

 The opening of the sodium channels that control the flow of current during the action potential
o A decrease in serum potassium causes the resting membrane potential to become more negative(hyperpolarization), moving further from the threshold for excitation. Therefore, it would take a greater stimulus to reach threshold and open the sodium channels that are responsible for the action potential

o An increase in serum potassium has the opposite effect; it causes the resting membrane potential to become more positive (hypopolarized), moving closer to the threshold
 It would take a lesser stimulus to reach the threshold and open the sodium channels that are responsible for the action potential
• Persistent depolarization inactivates the sodium channels
 The rate of repolarization
Manifestations. Hypokalemia alters the membrane potentials and excitability on cardiovascular, neuromuscular, and gastrointestinal function. List these symptoms.
Notice … in general, things are sloooooowed down, right?
 Cardiovascular
o Postural hypotension
o Predisposition to digitalis toxicity
o Electrocardiogram changes
o Cardiac arrhythmias
 Neuromuscular
o Muscle weakness, flabbiness, fatigue
o Muscle cramps and tenderness
o Paresthesias
o Paralysis (severe)
 Gastrointestinal
o Anorexia, nausea, vomiting
o Abdominal distention
o Paralytic ileus (severe)
 Increased thirst
 Inability to concentrate urine
 Polyuria
 Urine with low specific gravity
Hyperkalemia is a serum potassium level greater than 5.0 mEq/L.
Causes. List the 3 categories of causes and give examples of each.
o ******Decreased renal function-renal failure******* (Most common cause)
 Decreased renal elimination
o Decrease in aldosterone-mediated potassium
o Depression of aldosterone release caused by a decrease in renin or angiotensin II
o Impaired ability of kidneys to respond to aldosterone
 Excessively rapid administration
o Kidneys control potassium elimination, therefore IV solutions should not be administered until urine output has been assessed and renal function is adequate
 Movement of potassium from the ICF to ECF compartments
o Tissue injury-causes release of intracellular potassium into the ECF-diminish renal function

o Decrease in aldosterone-mediated potassium
o Depression of aldosterone release caused by a decrease in renin or angiotensin II
o Impaired ability of kidneys to respond to aldosterone
 Excessively rapid administration
o Kidneys control potassium elimination, therefore IV solutions should not be administered until urine output has been assessed and renal function is adequate
 Movement of potassium from the ICF to ECF compartments
o Tissue injury-causes release of intracellular potassium into the ECF-diminish renal function
Manifestations. What are the effects of hyperkalemia on neuromuscular, gastrointestinal, and cardiovascular systems?
Notice things are slow again … one would think the effects would be the opposite of hypok+ and initially they are, but the later effects differ because persistent depolarization inactivates the sodium channels and produce a decrease in excitability (p. 124).
 Cardiovascular
o Electrocardiogram changes
o Risk of cardiac arrest (severe)
 Neuromuscular
o Weakness, dizziness
o Muscle cramps
o Paresthesias
o Paralysis (severe)
 Gastrointestinal
o Nausea, vomiting
o Intestinal cramps
o Diarrhea
 Transient hyperkalemia may be induced by exercise or seizures when muscle cells are permeable to potassium
Ionized calcium, which leaves the vascular space, serves what functions?
 Many enzyme reactions
 Exerts an important effect on membrane potentials and neuronal excitability
 Necessary for contraction of skeletal, cardiac, and smooth muscle
 Participates in the release of hormones, neurotransmitters, and other chemical messengers
 Influences cardiac contractibility and automaticity by way of slow calcium channels
 Essential for blood clotting
Describe the physiologic mechanisms that regulate calcium.
Calcium enters the body through the gastrointestinal tract, is absorbed from the intestine, thanks to Vitamin D. Calcium is stored in bone and is excreted by the kidney.

What hormone is the major regulator of serum calcium?
 Parathyroid Hormone (PTH)
Mechanisms involved in PTH’s regulation of serum calcium.
1. Promotes the release of calcium from the bone.
2. Increases activation of Vitamin D.
3. Stimulates calcium retention and phosphate elimination in the kidneys.
Describe the Renin-angiotensin, aldosterone system
Regulates sodium excretion and absorption.
What is Angiotensin II?
Acts directly on renal tubules to increase sodium reabsorption.

Acts to constrict renal blood vessels, thereby decreasing the glomerular filtration rate and slowing renal blood flow so that less sodium is filtered and more is reabsorbed.
Functions of Aldosterone
Acts at the level of the cortical collection tubules of the kidney to increase sodium reabsorption and while increaing potassium elimination.
Most of sodium in in the _____ compartment
extra cellular
dibetes insipidus
deficiency of or decreaed response to ADH.
Results in polyuria.
Intense thirst.
Hypernatremia (fluid excreted, higher concentraion of sodium).
Dehydration
SIADH
Marked water retention, and dilutional hyponatremia

Urine output decreases
Serum sodium decreases
BUN levels dcrease
Dilutional hyponatremia (retaining too much fluid, lower concentration of sodium)
Isotonic Fluid Volume deficit
proportionate loss of sodium and water
hypovolemia
when the effective circulating blood is compromised
Causes of isotonic fluid volume deficit
when water and electrolytes are lost in isotonic proportions.
Almost always accompanied by a loss of body fluids
Pften accompanied by a decrease in fluid intake.
Signs and symptoms of isotonic fluid volume deficit
dehydration and related symptoms
postural hypotension
shock
weak pulse
decreased blood pressure
signs of water conservation by the kidney
dry mucous membranes
skin turgur
Isotonic fluid volume excess
Can be pathological or compensatory
Most commonly caused by a decrease in sodium and water elimination by the kidney
Caused by proportional increase in sodium and water
Manifestations of Isotonic Fluid volume excess
weight gain over short time
edema
distended jugular veins
full pulse
elevated central venous pressure
BUN and hematocrit decreased
Lung edema-shortness of breath productive cough
For low sodium, think ________
brain (cerebral swelling)

Hyponatremia aka fluid volume excess

water retention

edema related disorders (conjestive heart failure)

DISORIENTATION
Seizure
Coma
headache
Lethargy
for high sodium (hypernatremia), think _______
dehydration
aka fluid volume deficit

Caused by rapid ingestion of sodium, defect in thirst, or inability to drink.

Most likely in infants and people who cannot express their thirst or obtain a drink
s/s hypernatremia
dehydration
decreased reflexes
seizures coma
weak rapid pulse
In metabolic acidosis, what happens to H+?
H+ ions move into cells >>>> potassium leaves the cell, making the cells more acidic
What happens to H+ in metabolic alkalosis
H+ ions leave the cells>>>> potassium enters the cells
Insulin and catecholamines
decrease serum potassium levels by increasing cellular uptake of potassium
What does aldosterone do to potassium?
In the presence of aldosterone, sodium is transported back into the blood

Potassium is secreted into tubular filtrate for elimination through the urine
How does thee Potassium hydrogen exchange system work?
When serum potassium levels are increased, potassium is secreted into the urine and hydrogen is reabsorbed into the blood, leading to a decrease pH and metabolic acidosis

When potassium levels are low, potassium is reabsorbed and hydrogen is secreted into the urine, leading to metabolic alkalosis
_________ __________ causes potassium to move out of cell into the ECF
serum osmolality
98% of the body's potassium is _____
intracellular
The body stores potassium where?
muscles
K+ critical role is...
assisting in nerve impulses and the excitability of skeletal, cardiac, and smooth muscle
3 ways potassium assists in nerve impulses
Regulates Resting Membrane Potential

Regulates the opening of the sodium channels that control the flow of current during an action potential

Regulates the rate of repolarization
Since hypokalemia moves the resting membrane potential further from the threshold for excitation , it requires a _______ stimulus to reach the threshold
greater
Hyperkalemia moves out of the RMP closer to the threshold causing an initial increase in membrane excitability, but with severe hyperkalemia, sodium channels become inactivated resulting in a net _________ in excitability
decrease
Hypokalemia ________ the rate of repolarization, whereas hyperkalemia ________ the rate of replarization
decreases

increases
When calcium goes up, ________ goes down
PHOSPHATE LEVELS and PTH
When PTH goes up, what goes down?
calcium
caused by increase in ADH
hyponatremia
caused by chronic renal failure
FVE
manifestations most resemble those of FVD
hypernatremia
most likely to be accompanied by hypotension and tachycardia
FVD

Hypernatremia
Most likely to affect brain cells and cause altered personality and behavior
hyponatremia and fluid volume excess
caused by an increase in aldosterone
FVE
Factors that can lead to SIADH
stress pain head injury HIV, certain drugs, certain cancers
SIADH involves....
over production of ADH, causing fluid retention and edema. Dilution of solutes such as sodium (which causes hyponatremia) and dilution of RBC, which leads to Anemia.
The hormone most likely to be involved if BOTH sodium and water (isotonic) is...
aldosterone
In DI, the kidneys do not respond to...
ADH
Hormones such as insulin and epipenephrine facilitate movement of K+ _________ the cells.
into
Severe excercise and cell trauma (burns, or excessive GI activity for example) can cause K+ to move ____ the blood.
into
Pt has conjestive heart failure, both pulmonary and generalized edema, and venous distention. What disorder does the Pt have?
FVE
The Pt has adrenal insufficiency (Addisons Disease), what does the Pt have?
FVD

dehydration, hypotension (decreased cardiac output)
Pt was in an extreme temperature at his home with no AC, his eyes were sunken and his skin turgor and capillary refill were both diminished. What does the PT have?
Hypernatremia

FVD