Exam 1 lecture 5 Flashcards
CrCl formula
(SCR x 72)
That is for males. Multiply by 0.85* for females
When to use CrCl? when not to use CRCL?
Use for patients that have stable kidney function, never for AKI patients
IBW formula
IBW men- 50+2.3(inches over 60)
IBW women- 45.5 + 2.3 (inches over 60)
When to use adjusted body weight? Formula?
AdjBW= IBW + 0.4 (ABW-IBW)
Use is patient is >130% of IBW
What are the 4 functions of kidney
excretes waste products of metabolism from the blood (urea/uric acid)
regulates bodys concentration of water and salt
Maintains acid balance of plasma (secretes H+ ions)
synthesizes calcitrol
secretes hormones (erythropoietin)
What is uremia
Build up of waste products in blood.
Uremia monitoring parameters
(Increased BUN, pruritis, confusion, nausea)
How does the kidney maintain PH of plasma
secretes H+ ions
What are the 5 complications that could result when the functions of the kidney are compromised
- metabolism & excretion- uremia
- fluid regulation- edema
- Acid balance of plasma- acidosis, electrolyte imbalances
- calcitrol synthesis- Mineral and bone disorder
erythropoietin secretion- Anemia
What is uremia caused by
Accumulation of waste molecules in blood that are normally removed by kidney
What should we monitor in uremia pts
BUN
BUN normal range
Normal BUN< or = 15
effects of uremia on body
Encephalopathy
uremic factor (breath)
nausea
uremic frost on skin (itching)
how does kidney disease effect removal of fluid in body
Kidney disease leads to fluid retention. This will lead to edema and increased BP
How to treat patients with diuretic resistance
Use a loop diuretic with a thiazide
Where do loop diuretics exert effect
Loop of henle
Why is using thiazides and loop diuretics more effective than just using loop diuretics
loop diuretics block sodium in loop of henle.
eventually these sodium molecules pass loop and go to DCT.
Cells in DCT start uptaking Na and water goes with Na. Loop diuretics stop working. We can use thiazides to block DCT.
T/F if one loop diuretic stops working we can try using another loop diuretic
False, poor response to one means poor response to all.
Thiazides are ineffective when CRCL os
Less than 30
Loops work below 30
Loop diuretic that is not a sulfa type drug?
Ethacrynic acid
patients that have sulfa allergies can use this as loop diuretic
Loop diuretics examples that have sulfa
Furosemide, bumetadine, torsemide
Effect of kidney decline on electrolyte imbalance
patients hold on to sodium if their kidney declines.
What to do in patients that have electrolyte imbalances (K and Na)
There is no need to severely restrict sodium beyond a no salt added diet (<2 g sodium per day) or <5g NaCl)
Make outpatients aware of foods with high sodium (hotdogs, canned soup)
restrict K to <3gm/day
avoid high K foods (tomatoes, dried fruits, salt substitute)
We can use dialysis for hyperkalemia pts
How does progressive kidney disease affect phosphate excretion
PKD leads to impaired phosphate excretion. This leads to phosphate retention.
How does progressive kidney disease lead to osteoporosis and bone disorder
-Impaired PO4 excretion
-leads phosphate retention
- leads to hypocalcemia (due to formation of calcium phosphate in blood)
- leads to an increase in PTH production
- leads to hyperparathyroidism
-parathyroid hormone pumps out Ca into blood, gets Ca from bones
-leads to osteoporosis
How does phosphorous retention caused by progressive kidney disease cause hypocalcemia
Phosphate binds calcium in blood, forming calcium phosphate (soft tissue calcification), this leads to less free calcium. This calcium phosphate leads to formation of rocks that deposit in body.
How does hypocalcemia affect PTH
low calcium leads to increased PTH secretion, causing Ca to be pumped out of bones, leading to osteoporosis
Where is vit D activated
Kidney
what effect does kidney deterioration have of vit D and the body
Usually, vit D is activated in kidney, when kidney deteriorates, it does not activate vit D
This leads to decreased intestinal absorption of phosphorous and calcium, leading to hypocalcemia.
This causes the parathyroid gland to produce PTH
PTH pumps Ca out of blood, leads to osteoporosis
What are the 3 main factors that cause an increase of PTH leading to osteoporosis
increased PTH
Decreased Ca
decreased vit D
T/F hyperphosphatemia is a problem for all ESRD patients
True
What is a normal phosphorous range
2.5-4.5
Can we pull phosphorous out of the blood once it is in?
No
What is the only way to make phosphorous go down?
Being used in normal biologic activities
Two ways to manage phosphorous inside body
diet
phosphate binders
What are the two types of phosphate binders
Calcium containing phosphate binders
non-calcium containing phosphate binders
Name the calcium containing phosphate binders
Tums (calcium carbonate)
calcium acetate (phosLo)
mechanism behind calcium phosphate binders
Calcium binds phosphorous before it gets absorbed (may cause soft tissue calcification)
always give with food. absorbs phosphate from food
calcium carbonate mechanism
give with food to prevent absorption of of po4
What number must not be exceeded with tums (calcium carbonate)? why?
1500 mg/d of elemental calcium.
may get absorbed in blood and bind phosphate, soft tissue calcification.)
What percent elemental calcium is tums
40%
what percent elemental calcium is phosLo? What is the maximum amount to take per day?
25%
1500 mg/day
side effects of phoslo and tums
Constipation
do not exceed 1500 mg /day for either
What patients do we not use (calcium acetate) phoslo or tums in
Pts with high phosphate, could cause soft tissue calcification
how many g of elemental calcium in a tums
300
how many g of elemental calcium in phoslo
169
what are some non-calcium containing phosphate binders
sevelamer carbonate(renvela)
lanthanum carbonate (fosenrol)
sucroferric oxyhydroxide (velphoro)
Auryxia (ferric acetate)
which phosphate binder reduces LDL and uric acid
sevelamer carbonate
Is sevelamer absorbed?
No
dose of sevelamer
14gm/day x 8 days
ADR for sevelamer
NONE
maybe a little stomach upset
What is the unique thing about lanthanum
maintains efficacy over broad PH range
how is lanthanum eliminated
feces, does not cross BBB.
mechanism of sucroferric oxyhydroxide
Contains Iron, iron binds phosphate so strongly that it does not get absorbed into body.
Does sucroferric oxyhydroxide get absorbed in the body?
No, iron levels do not change
Which non calcium phosphate binder abxorbs iron in body (can be used for patients with low iron?
auryxia (ferric acetate)
why should we not use amphojel (aluminum hydroxide?
can cause kidney toxicity (Al eliminated by kidney)
dietary phosphorous intake should be restricted to
800-1000 mg/day
what are some foods high in phosphorous
meat, nut dairy, dried beans, colas, beer
