CKD and ESRD Lecture Flashcards
Major causes of CKD
Diabetes; HTN; Glomerulonephritis
KDIGO definition of CKD
abnormalities of kidney structure present for more than 3 months with implications of health
KDIGO classifies CKD by what categories?
Cause, GFR, and albuminuria cateogry
What level does GFR have to be at to be considered CKD
GFR has to be below 60 mL/min/1.73 m^2
Kidney Failure has a GFR of _____ and has the category name of ____
< 15; G5
Albuminuria levels for CKD
normal - mild < 30
moderate: 30 - 300
severe: > 300
(units: mg/24 hours)
Normal GFR level
above 90 mL/min/1.73 m^2
Cockroft Gault Equation is an equation for what?
finding CrCl
What is the Cockroft Gault equation
If male: CrCl =
(140 - age) IBW/ (SCr x 72)
If female - same thing but x .85
Cockroft gault formula tends to _______ renal function in moderate to severe kidney impairment
overestimate
MDRD is used for what?
measure GFR and it is used to stage kidney disease
Components of MDRD equation
Age; Sex; Race
What does MDRD stand for
modification of Diet in renal disease
IBW equations
male: 50 kg + (2.3 x inches of 60 in)
Female: 45.5 + (2.3 x inches of 60 in)
Main functions of Kidney
- excrete waste products
- regulates body’s concentration of water and salt
- maintain acid balance of plasma
- secrete hormones
- synthesize calcitriol
What waste products does the kidney get rid of from the blood
urea, ammonia, bilirubin, uric acid
If the kidney cannot get rid of waste products - the waste products build up and cause
UREMIA: increase in BUN; pruritis; confusion; nausea; vomiting; anorexia
If the body cant regulate the bodys water and salt concentrations - what happens
edema; fluid overload; CV complications
what happens if the kidney cant maintain acid balance of plasma
metabolic acidosis - because it CANT EXCRETE H+ ions
what hormones does the kidney secrete
erythropoeitin, rennin, PGAs
what happens if the kidneys cant secrete hormones
Anemia - erythropoeitin is needed to make RBCs
What happens if the kidney cant make synthesize calcitriol
mineral and bone disorder/ increased levels of PTH
another name for calcitriol
active form of Vit.D
Common effects of Uremia
- Uremic fetor (urine breath)
- encephalopathy (confusion)
- Uremic frost (uric acid crystals on skin)
- Nausea and Vomiting
- Edema
- Mineral and bone disorder
- Anemia
How to regulate fluid retention in a CKD patient
regulate Na intake!!! not so much fluid restriction - but AVOID lots of free water
Do diuretics work when a patient does NOT make urine?
no they do not work
Explain Diuretic Resistance
When Loop diuretics are used - Distal tubule is exposed/”bathed” in lots of Na - which makes the distal tubule reabsorb more Na and therefore more water is absorbed too - thus making the loop less effective
How to treat diuretic resistane
give a thiazide diuretic to work at the Distal tubule to stop the NaCl transporter to stop absorbing Na (and water)
How to treat fluid overload when on dialysis
just adjust settings on dialysis machine
Electrolyte imbalance cautions for CKD
Na and K
K amount is restricted to _____
3 gm/day
Steps on how to treat hyperkalemia
1) calcium gluconate
2) insulin/D5W
2) albuterol
3) sodium polystyrene sulfonate
3) dialysis
What are high potassium foods
tomatoes; dried fruits; salt substitutes; fresh fruits
Sodium bicarbonate - not used for what kind of patients?
ESRD
Key Points of Mineral and Bone Disorder
1 - hyperphosphatemia
2 - decrease in (activated) Vit. D
3 - hypocalcemia
Why does hyperphosphatemia happen with kidney disease
Kidney cannot excrete it - therefore phosphorous accumulates
Why does decreased Vit. D happen with CKD
kidney is messed up - therefore cant make calcitriol
2 major classes of drugs to help treat Hyperphosphatemia
Phosphate binders -
Calcium containing OR Non-Calcium Containing
Overall Effect of Mineral - Bone Disorder (CKD)
increased iPTH - which leads to the bones being broken down to release more calcium form the bones
Renvela/ Sevelamer carbonate - facts about it
- little bit of GI issues;
- Not absorbed = low risk of toxicity
- decrease uric acid serum concentrations
- decreases LDL levels
is a NON CALCIUM CONTAINING PHOSPHATE BINDER
Drugs that are NON-CALCIUM CONTAINING PHOSPHATE BINDER
Sevelamer Carbonate (Renvela) Lanthanum Carbonate (Fosrenol) Sucroferric Oxyhydroxide (Velphoro) Auryxia (ferric citrate) Aluminum Hydroxide (Amphojel)
Drugs that are calcium containing phosphate binders
Tums (Calcium Carbonate) and Calcium acetate (PhosLo)
Important facts about Auryxia
- contains iron that can be absorbed to affect TSAT and ferritin
- is a non calcium containing phosphate binder
- darken stool bc iron
important facts about lanthanum carbonate (fosrenol)
- is eliminated in feces - no worry about accumulation of lanthanum long term
- keeps it efficacy regardless of pH of stomach (3 - 5)
- does not cross blood brain barrier
Two iron containing phosphate binders
Auryxia and Sucroferric oxyhydroxide
Dietary Restriction for Phosphate
800 - 1000 mg/ day
Foods that contain high amounts of phosphorus
meat, nuts, dry beans, dairy, cola, beets
Caution of Phosphate binders and TPN patients
phosphate binders work in GI tract - if TPN being used - GI tract is not being used - therefore no need to use phosphate binders in TPN
Stage 3/4 CKD pts vs Stage 5 (ESRD) pts -
Vitamin D supplementation
if 3 or 4 - give INACTIVE FORM - Ergocalciferol (Calciferol) - Vit D2 or Cholecalciferol - Vit D3
if 5 - give ACTIVE FORM (bc kidney cant make inactive form into active)
active forms of Vit. D to give ESRD pts
Calcitriol; Paricalcitol; Dexercalciferol
Inactive forms of Vit. D to give to CKD stage 3/4 pts
Ergocalciferol; Cholecalciferol
Out of the Active forms of Vit. D to give to a patient - which one has the biggest risk of hypercalcemia
Calcitriol
out of the active forms of Vit. D to give a patient - which one has least risk of causing hypercalcemia
Paricalcitol and Doxercalciferol
Which active form of Vit. D is a PRO-HORMONE
Doxercalciferol
Importnat note to Doxercalciferol
its a pro-hormone - must be metabolized by LIVER
also gives more even serum concentrations
Why is important for Vit. D supplements to have a LOW CALCEMIC activity
because patients already have high phos levels - if too much Ca = more risk for precipitation
Which active form of Vit. D has a higher risk of hyperphosphatemia
Doxercalciferol
What drug should be avoided in patients that are alcoholics or have multi organ failure?
the Pro-hormone drug - Doxercalciferol
Name for calcimimetic agent for treating calcium homeostasis
Cinacalcet (Sensipar)
Mechanism of Cinacalcet
it mimics action of calcium by binding to calcium sensing receptor on parathyroid - causes conformational change of receptor to send signal to parathyroid to decrease PTH production
Cinacalcet is contraindicate in patients with what?
hypocalcemia
Hypocalcemia is a contraindication for what drug
cinacalcet (if Calcium is less 7.5 mg/dL)
Possible mechanisms for anemia in ESRD pts
1 - DECREASED PRODUCTION OF ERYTHROPOIETIN
2- uremia causes decreased half life span of RBCs
3- vitamin losses during dialysis (folate, B12, B6)
4- dialysis - loss of blood through dialyzer
What is MCV
mean corpuscular volume - average size of RBCs
what are the 3 main types of anemia (related to MCV)
microcytic, normocytic, macrocytic
Iron deficiency causes what kind of anemia (micro, normo, macro - cytic)
micro!
Vitamin deficiencies (folate, B12) cause what kind of anemia (micro, normo, macro - cytic)
macro!
GI bleed or Erythropoetin deficiency can cause what kind of anemia (micro, normo, macro - cytic)
normocytic
what is RDW?
red cell distribution width -
when is RDW important?
if pt has both macrocytic and microcytic anemia - the blood cell volume range is much larger
what is the average value for RDW
11.5 -14.5%
What is the preferred way to assess anemia
Hemoglobin (not hematocrit)
why is Hgb preferred over Hct for anemia monitoring parameters
Hgb is more stable
Hemoglobin Levels to see if a patient is Anemic
Females: ?
Males: ?
Females: < 12 g/dL
Males: < 13 g/dL
What is erythropoiesis and what does it require
makes RBCs - need IRON!!
When to recommend iron supplementation
TSAT: < 30%
and
serum ferritin < 500 ng/mL
when to give oral iron vs IV iron?
oral - stage 3 or 4 CKD patient
IV - stage 5 CKD patient
Iron is best absorbed in what kind of environment?
acidic! (therefore avoid eating with it or taking antacids/PPIs/H2 antagonists)
what drugs should be avoided/separated from iron supplements
antacids/H2 antagonists/PPIs - because they decrease acidity of stomach and therefore absorption
Note about enteric coated iron tablets
enteric = absorbed in small intestine - but less acidic = less absorption
iron and ___ should be separated from each other by about 2 hours due to _______
Calcium; tight binding
Low molecular vs High Molecular weight IV iron
high = higher chance of anaphylactic reaction
Which IV iron needs a test dose
iron dextran
two kinds of Iron dextran and why they are different
Infed - low molecular weight
Dexferrum - high molec weight
Heme iron qualities
absorbed in a different site - NOT relevant to the 200 mg elemental iron rule
Oral iron: need ______ of elemental iron per day - at least!
200 mg
If iron doesn’t work - start using ______
erythropoesis stimulating agents
When to start use ESAs?
If stage 3/4 vs stage 5
3/4: if Hb < 10 g/dL
5: when Hb is b/w 9 and 10
Do not use ESA to push Hb above _____ g/dL
11.5
2 kinds of ESAs
Recombinant human erythropoietin and Darbepoetin alfa
Difference between the 2 ESAs
Darbepoetin alfa - has a longer half life!
ESA adverse effects
Pure Red cell aplasia (PRCA) = antibodies develop to erythropoietin
AND
HTN
Common reasons ESA fails
lack of IRON (and vitamins)
active bleed
Protein Requirement for CKD and then ESRD
CKD: 0.8 g/kg/day (if GFR is < 30 mL/min)
ESRD: 1.2 g/kg/day
What types of vitamins should be replaced when on dialysis
water soluble - B and C
Two types of vascular access for Hemodialysis
AV fistula and AV graft
Differences b/w AV fistula and graft
fistula - sew an artery into a vein to make it more strong
graft - “foreign body”/plastic put into body to make vein and artery connected
AV graft or AV fistula?
Fewer complications
fistula
AV graft or AV fistula?
Poses a problem for diabetics (due to PVD - weak veins)
Fistula
AV graft or AV fistula?
Has the shortest time to “mature”
graft
AV graft or AV fistula?
Hast the longest time to “mature”
fistula
AV graft or AV fistula?
uses a synthetic material to
graft
AV graft or AV fistula?
has higher infection rate
graft
KEY NOTE about the ACESS ARM once a AV fistula or graft is made
NO needle pricks on that arm AND NO BP cuff on that arm
What kind of substances are not removed by a dialysis machine
- high molecular weight
- high volume of distribution molecules (because a lot in tissue - not blood)
- high lipophilicity (because blood deals with water like solutions)
- highly protein bound (not free to be excreted)
Ways to measure the effectiveness of dialysis sesssions
Kt/V and URR (urea reduction rate)
what is Kt/V / what do the variables stand for
a way to measure the effectiveness of a dialysis session
K - clearance of urea
t - time on dialysis
V - volume of distribution of urea
Goal Kt/V value
1.4 (and above)
If Kt/V value is 0.9 - good or bad?
bad! - adjust the time on dialysis… to increase value
what is URR measuring
measuring the reduction of BUN
what is the goal URR
> 70%
(example of good session of dialysis:
BUN starts: 100
after dialysis BUN = 30)
Types of Peritoneal Dialysis
CAPD; CCPD; NIPD; TPD
Signs and Symptoms of Peritonitis
cloudy effluent (fluid coming out is cloudy = infection); fever, nausea; abdominal pain
Different ways to treat peritonitis
1st and 3rd generation Cephs; Aminoglycosides
Best way to give an antibiotic for peritonitis
intraperitoneal
Why is intraperitoneal route the best route for peritonitis infectoins?
1 - pt probably has N/V - cant do oral
2 - probably has vasular issues because they are periotneal (therefore no IV)
3 - infection usually isnt too deep - intraperitoneal is just fine
when to use CRRT (continuous renal replacement therapy)
- in ACUTE renal failure
- for patients that cannot handle normal dialysis sessions
3 main kinds of CRRT
hemofiltration; hemodialysis; hemodiafiltration
Hemofiltration (CAVH or CVVH) as a CRRT - key points about it
NO DIALYSATE bag; uses CONVECTION; ultrafiltrate added to keep BP up
CVVHD - hemodialysis as a CRRT - key points about it
regular dialysis but all day long; uses DIFFUSION (works better than convection)
CVVDHF - hemodiafiltration as a CRRT - key points about it
use diffusion AND convection; just like CRRT hemodialysis but the rate is increased (to create the convection)
The decline of kidney function based on SCr values is a ________ curve
sigmoidal
where is the biggest drop in kidney function when SCr increases
1 - 2
How do you measure CrCl for AKI?
PSYCHE! YOU DONT! Its changing too much to calculate it
Types of AKI (and how they are acquired)
Community (self inflicted) OR Hospital (hospital did it to ya)
Since we can’t use SCr for AKI - what do we look at as monitoring parameters?
- pts weight
- BP
- urine output
- urinalysis (Specific gravity, hematuria/proteinuria; microscopic exam)
Types of Urine Output Categories (related to AKI parameters)
anuria; oliguria; non-oliguria
what is oliguria
less than 400 mL of urine production in a 24 hr period
what is non-oliguria
more than 400 mL of urine production in a 24 hr period
If specific gravity is high - what kind of AKI could it be?
pre-renal or functional AKI
If Hematuria or proteinuria is present - what kind of AKI?
some kind of injury…. (?)
what can be seen in a microscopic examination
RBCs and Casts (of RBCs)
What is fractional excretion of Sodium?
- way to differentiate b/w prerenal/functional renal failure and intrinsic renal failure
- also means “can kidney still make concentrate urine”
Preventing AKI/AKI management
- Avoid ________ agents
- __________ - if nephrotoxic agent has to be used - make sure to use this kind of therapy to increase urine output and flush out the toxin
- _____ loading
- identify at risk patients
nephrotoxic; hydration; Na;
Patient groups that are at risk for AKI
Older pts; pts w/ abnormal renal function; diabetic pts; volume depleted pts
Main Goals of treating AKI
- remove primary cause
- limit further nephrotoxic exposure
- accelerate therapy
Two ways to control volume with AKI patients
CRRT (the 3 diff. kinds) and diuretics (loops)
List the common nephrotoxins
- NSAIDs/Cox II inhibitor
- Acetaminophen
- Aminoglycosides
- ACE inhibitors/Angiotensin II receptor blockers
- PROTON PUMP INHIBITORS (caution bc OTC)
(- Amphotericin B - Contrast Media
- Cisplatin/Carboplatin
- cyclosporine/tacrolimus
- lithium)
If filtration in the kidney decrease, _____ will increase
SCr
General Rule to start hemodialysis:
If BUN is > ______
or
SCr is > ______
100; 10
When starting a patient on an ACE inhibitor or ARB - what should be monitored closely
SCr - if it increase over 30% - dc the drug
NSAIDs increase SCr because of what mechanism?
afferent arteriole (to the glomerulus) will VASOCONSTRICTION - causes decreases renal perfusion and filtration pressure
ACEIs and ARBs increase SCr by what mechanism?
vasodilation of the efferent arterioles decrease the filtration pressure
Definition of ultrafiltrate
waste products removed during continuous renal replacement therapy
Most common reason that ESA treatment fails
lack of vitamins and iron
