CKD/Hemodialysis Flashcards
Major causes of kidney disease
-Diabetes mellitus
-Hypertension
-Glomerulonephritis
Physiologic functions of the kidney
-Excrete waste products of metabolism from the blood (i.e., urea, ammonia, bilirubin, uric acid etc.)
-Regulates body’s concentration of water and salt
-Maintains acid balance of plasma (secretes H+ ions)
-Synthesizes calcitriol (active from of vitamin D)
-Secretes hormones (erythropoietin, rennin, PGAs)
Complications associated with CKD and ESRD
-Uremia
-Fluid retention
-Electrolyte imbalances
-Mineral and bone disorder
-Anemia
Considerations when using diuretics
-Diuretics will not work in patients with no kidney function
-Thiazides are ineffective when CrCl < 30 ml/min
-Loops will work when CrCl < 30 ml/min
-Avoid potassium-sparing diuretics
-Thiazide may be added to loop diuretic as renal function declines to overcome diuretic resistance
Sodium considerations/counseling for CKD patients
-No salt diet
-Use saline containing IV solutions
-Make outpatients aware of hidden high-sodium-content foods
-Less than 2g sodium/day or 5g NaCl
Potassium considerations/counseling for CKD patients
-Restrict to 3 gm/day
-Goal for ESRD patient is a pre-dialysis K concentration of 4.5 – 5.5 mEq/L
-Avoid high potassium foods
Mechanism of action for phosphate binders
These agents bind dietary phosphate which is ingested in the food and the chelate is eliminated in the feces
MUST BE GIVEN WITH EVERY MEAL
Tums drug class
Calcium containing phosphate binder
(Calcium carbonate)
PhosLo drug class
Calcium containing phosphate binder
(Calcium acetate)
Main difference between Tums and PhosLo
Calcium acetate will bind twice as much phosphate compared to calcium carbonate. Calcium acetate may produce fewer hypercalcemic events when compared to calcium carbonate
Renvela drug class
Non-calcium containing phosphate binder
(Sevelamer carbonate)
Fosrenol drug class
Non-calcium containing phosphate binder
(Lanthanum carbonate)
Velphoro drug class
Non-calcium containing phosphate binder
(Sucroferric oxyhydroxide)
Auryxia drug class
Non-calcium containing phosphate binder
(Ferric citrate)
Renvela considerations/counseling
-Side effects: mild GI upset, nausea, vomiting, diarrhea
-Decreases LDL 15-30%
-Not absorbed
-Decreases uric acid
-Very hard to overdose
Fosrenol considerations/counseling
-Binds very well in acidic pH
-Excreted in feces
-No long term accumulation
-Does not cross BBB
-Mild GI upset
Difference between Velphoro and Auryxia
Auryxia increases iron levels while Velphoro does not
When should Amphojel (aluminum hydroxide) be used?
Never
Dietary restrictions for patients with hyperphosphatemia
Dietary phosphorous should be restricted to 800 to 1000 mg per day if:
-Phos >4.6 mg/dL (CKD stage 3 and 4)
-Phos >5.5 mg/dL (CKD stage 5)
-PTH > 55
Inactive form of vitamin D in the body
25-hydroxyvitamin D [25(OH)D]
Active form of vitamin D created by the kidney
1,25-dihydroxyvitamin D [1,25(OH)2D3]
Enzyme in the kidney that converts inactive vitamin D to active form
1-alpha-hydroxylase
Calciferol drug class
Inactive vitamin D compound
(Ergocalciferol)
(Vitamin D2)
Cholecalciferol drug class
Inactive vitamin D compound
(Vitamin D3)
Rocaltrol/Calcijex drug class
Activated vitamin D compound
(Calcitriol)
Zemplar drug class
Activated vitamin D compound
(Paricalcitol)
Hectorol Drug class
Activated vitamin D compound
(doxercalciferol)
Sensipar drug class
Type II calcimimetic agent
(Cinacalcet)
Parsabiv drug class
Type II calcimimetic agent
(Etelcalcetide)
Inactive calcium vs. active calcium
-Inactive vitamin D is used for patients with stage 3 and 4 CKD while active vitamin D is used for patients with stage 5 CKD
-Inactive is better to use than activated
Difference between Rocaltrol and Calcijex
Rocaltrol is oral and calcijex is IV
Calcitriol considerations/counseling
-Monitor signs and symptoms of hypercalcemia
-Approved for pediatric use
-Greatest risk of hypercalcemia
Paricalcitol considerations/counseling
-30% reduction in iPTH
-Most favorable adverse drug reaction profile
-Less calcemic activity compared to calcitriol
-Monitor signs and symptoms of hypercalcemia
Doxercalciferol considerations/counseling
-Produces a more even serum concentration than calcitriol
-30% reduction of iPTH
-Lower incidence of hypercalcemia compared to calcitriol
-Higher incidence of hyperphosphatemia
-Prodrug and must be activated by the liver
What are calcimimetics contraindicated in?
Hypocalcemia (Ca <7.5 mg/dL, withhold cinacalcet/etelcalcetide until Ca is = or > 8 mg/dL)
Mechanism of action of calcimimetics
Mimics the action of calcium but does so by binding to the calcium sensing receptor and inducing a conformational change to the receptor, triggering the parathyroid gland to decrease PTH secretion
The four ways ESRD patients can develop anemia
-Decreased production of erythropoietin
-Uremia causes a decreased life span of red blood cells
-Vitamin losses during dialysis – folate, B12, B6
-Dialysis – loss of blood through dialyzer
Low MCV
Microcystic
Increased MCV
Macrocystic
MCV is normal but RDW is increased
Normocystic
Characteristics of microcystic
-Iron deficiency
-Aluminum toxicity
Characteristics of normocystic
-Anemia of chronic disease
-Gastrointestinal bleed
-Erythropoietin deficiency
Characteristics of macrocystic
-Folate deficiency
-B12 deficiency
When to use oral iron vs iv iron
Oral iron cannot be absorbed by patients on hemodialysis
Oral iron considerations/counseling
-causes upset stomach
-Best absorbed in acidic environment
-Take with orange juice to increase absorption
-Will not work as well on patients taking meds that lower pH
-Separate from calcium by 2 hours
InFed or Dexferrum drug class
IV Iron
(Iron dextran)
Ferriclit drug class
IV Iron
(Sodium ferric gluconate)
Venofer drug class
IV Iron
(Venofer)
Injectafer drug class
IV Iron
(Ferric carboxymaltose)
Feraheme drug class
IV Iron
(Ferumoxytol)
IV Iron considerations/counseling
-Preferred route for CKD 5D patients
-Straight iron can kill the patient
-Flushing, dizziness, hypotension are possible with IV iron products
InFed, Dexferrum considerations/counseling
-Can be allergic to dextran
-Requires 25mg test dose
-Oldest and cheapest
Venofer considerations/counseling
Can be used on patients not on dialysis
Feraheme considerations/counseling
Feraheme interferes with magnetic resonance imaging for up to 3 months after the second injection. MR imaging should be completed prior to starting Feraheme
Order the three ESAs from shortest to longest half life
-Aranesp
-rHuEPO, epoetin alfa, Epogen, Procrit, EPO
-Micera
-Recombinant human erythropoietin (Procrit)
-Darbepoetin alfa (Aranesp)
-Methoxy polyethylene glycol (Mircera)
Causes of ESA therapy failure
-Lack of vitamins or iron
-Aluminum toxicity
-Active bleed
New therapy for anemia of chronic kidney disease
Hypoxia inducible factor (HIF) Prolyl hydroxylase inhibitors (PHI) or HIF-PHIs:
-Daprodustat (Jesduvroq)
-Indication: for the treatment of anemia due to chronic kidney disease in patients who have been on dialysis for at least 4 months
Indications for RRT
-Acid/base balance
-Electrolyte disturbances
-Intoxication
-Overload of fluid
-Uremia
Goals of dialysis
-General rule is to initiate when BUN >100, SCr >10
AV fistula access
-Longest survival rates
-Fewer complications
-Takes 1-2 months to mature
-No needle sticks or blood pressure cuffs on access arm
-Using catheter can increase infection rate by 30x
AV graft access
-Synthetic
-Shorter survival (foreign object in body)
-Increased infection rates
-2-3 weeks to mature
What substances are not removed by dialysis?
-High Vd
-High lipophilicity
-High hydrophilicity
-Large molecular weight
-Highly protein bound
How do you measure effectiveness of a dialysis session?
-Kt/V
-Urea reduction rate (URR)
Complications caused by hemodialysis
-Hypotension
-Puritus
-Muscle cramps
Peritoneal Dialysis
-Uses patients peritoneal membranes as dialysis membrane
-Mostly reserved for pediatrics or ESRD patients already receiving PD
-Rarely used for acute renal failure (ARF) except in children
-Not as effective as hemodialysis, but is a continuous therapy
-Residual renal function is preserved so kidneys will continue to work
-Best used on patients with large bellies
Continuous ambulatory peritoneal dialysis (CAPD)
Replaces bag every 4 hours in the day then leaves fluid in at night to then replace in the morning
Continuous cyclic peritoneal dialysis (CCPD)
Leaves fluid in during the day then at night a machine takes the fluid in and out
Nocturnal intermittent peritoneal dialysis (NIPD)
No fluid is in the peritoneum during the day but then at night a machine preforms very rapid exchanges
Tidal peritoneal dialysis (TPD)
Puts in half of the fluid into the peritoneum then exchanges the other half throughout the night
What is continuous renal replacement therapy used for?
-It is primarily used for acute renal failure
-Continuous renal replacement therapies were developed for those patients who could not tolerate regular hemodialysis sessions
