Renal & Liver Disease: Renal Disease Flashcards
Acute Kidney Injury (AKI)
A sudden loss of kidney function
Often reversible, can be permanent if cause isn’t corrected
Can be Drug-induced, common cause is dehydration (presentation w/ BUN:SCr ratio > 20:1, dec urine output, dry mucus membranes, and tachycardia)
Chronic Kidney Disease (CKD)
Progressive loss of kidney function over months/years.
Degree of kidney function assessed based on GFR or CrCL, and how much albumin in urine
Kidney Failure (ESRD)
Total and permanent kidney failure.
Fluid and waste accumulates, dialysis or transplant is required to perform the functions of kidneys
Primary function of the nephron & Kidney
to control concentration of sodium and water
reabsorb what is needed back into the blood, excreting rest in urine
regulates blood volume and BP
Afferent arteriole (direction)
delivers blood into the glomerous
Efferent arteriole (direction)
blood exiting the glomerous
Major parts of nephron in order
- Bowman’s Capsule
- Glomerous
- Proximal tubule
- Loop of Henle
- Distal Convoluted Tubule
- Collecting Duct
Drugs that work on the Proximal tubule
SGLT2 inhibitors
Drugs that work in the Loop of Henle
Loop diuretics work in Ascending Limb of the Loop of Henle
How do Loop diuretics work?
Inhibit the Na-K pump, leading to less Na being reabsorbed into the blood, causing less water to be reabsorbed and more to be excreted
Also cause less Calcium reabsorption into the blood, leading to Ca depletion and long term use can lead to decreased bone density
What does the distal convoluted tubule regulate?
Potassium (K), Na, Ca, and pH
only about 5% Na reabsorbed here
Which drugs work at the distal convoluted tubule?
Thiazide diuretics
How do thiazide diuretics work?
Since only 5% Na reabsorbed here, weaker diuretics than loops
Thiazides increase Ca reabsorption at the Ca pump in distal convoluted tubule
Long term use has protective effect on bones unlike loop diuretics
Which drugs work at collecting duct & distal convoluted tubule?
Potassium- sparing diuretics (inc aldosterone antagonists) ie spironolactone, eplerenone
Select drugs that can cause Kidney Disease
Aminoglycosides
Amphotericin B
Cisplatin
Cyclosporine
Loop Diuretics
NSAIDs
Polymyxins
Radiographic contrast dye
Tacrolimus
Vancomycin
Cockcoft-Gault Equation
((140-patient age)/( 72 X SCr)) X weight kg X 0.85 (if female)
When is Cockcrof-Gault equation no recommended
very young children
in kidney failure
unstable renal function
accuracy decreased in elderly, w/ low muscle mass
GFR: Stage 1 CKD
> 90 + kidney damage
GFR: Stage 2 CKD
60-89 + Kidney damage
GFR: Stage 3 CKD
45-59 = a
30-44 = b
GFR: Stage 4 CKD
15-29
GFR: Stage 5 CKD
< 15 or dialysis dependent
KDIGO target SBP for HTN/CKD patients
SBP < 120 mmHG
1st line HTN treatment for patients with CKD & HTN
ACEi or ARB
SCr can bump by up to 30%, shouldn’t stop unless increase > 30%
ACEi and ARB use in CKD patients
Shouldn’t be used together
Can increase potassium, patients should avoid potassium supplements and sal substitutes
Serum creatinine and potassium monitoring in CKD patients on ACEi or ARB
2-4 weeks after starting
KDIGO guidelines for diabetes management in CKD
use a SGLT2i (canagliflozin, dapagliflozin, and empagliflozin
has shown reduction in CV events and CKD progression
if cant use, GLP-1 receptor agonist recommended
Finerenone (nonsteroidal mineralocorticoid receptor antagonist) can be added to SGLT2i & max tolerated ACEi/ARB if eGFR > 25mL/min
Drugs CI CrCl < 60 mL/min
Nitrofurantoin
Drugs CI CrCl < 50mL/min
Tenofovir disoproxil fumarate (TDF products)
Voriconazole IV
Drugs CI CrCl < 30mL/min
Tenofovir alafenamide (TAF)
NSAIDs
Dabigatran
Rivaroxaban
Which levels to monitor for CKD patients?
parathyroid hormone (PTH)
phosphorus (phosphate, PO4)
calcium
Vitamin D
How to treat hyperphosphatemia?
1st: Restrict dietary intake of phosphate (avoid dairy, chocolate, nuts)
2nd: Phosphate binders
Types of Phosphate binders?
aluminum based
calcium based
aluminum/calcium free
When to take phosphate binders?
take prior to/ start of meal
if dose is missed, dose should be skipped and regular dosing at next interval
Aluminum based phosphate binder info:
potent, rarely used due to toxicity for CNS/bone toxicity
txm duration limited to 4 weeks
Aluminum hydroxide suspension info
Dose: 300-600mg TID w/ meals
SE: aluminum intox, dialysis dementia, constipation, nausea
Monitoring: Ca, PO4, PTH, s/x of aluminum tox
Calcium based phosphate binder info:
1st line
Calcium acetate (Phoslyra)
Calcium carbonate (Tums)
Calcium acetate binds better than calcium carbonate
Hypercalcemia problematic with Vit D use due to increase calcium absorption
Calcium acetate (Phoslyra) info
Dose: 1,334mg PO TID w/ meals…..titrate based on PO4 levels
Calcium carbonate (Tums) info
Dose: 500mg PO TID w/ meals….titrate based on PO4 levels
Total daily dose should be < 2,000mg elemental calcium
Phosphate binders should be separated from the administration of…..
Levothyroxine
Quinolones
Tetracyclines
Sucroferric oxyhydroxide (Velphora) Info
Dose: 500mg TID w/ food, titrate based on PO4 lvls
SE: D/constipation, black poop
Monitor: PO4, PTH
$$$$$
Ferric citrate (Auryxia) info
Dose: 2 tabs TID w/ meals, titrate based on PO4 lvls
Warnings: iron absorption occurs, may have to reduce IV iron dose
SE: D/ constipation, black poop
Monitor: Iron, ferritin, TSAT, PO4, PTH
$$$$$
Lanthanum carbonate (Fosrenol) info
Dose: 500mg TID w/ meals, based on PO4 lvls and chew thoroughly
CI: GI obstruction, fecal impaction, ileus
Warning: GI perforation
SE: N/V/D/constipation
Sevelamer carbonate (Renvela) & Sevelamer hydrochloride (Renagel)
Dose: 800-1600mg TID w/ meals, titrate as needed
CI: Bowel obstruction
Warning: can reduce Vitamin absorption, consider supplements
SE: N/V/D
** Can lower cholesterol & LDL by 15-30%**
Vitamin D deficiency occurs when….
kidney unable to turn Vitamin D into final active form 1,25 - dihydroxy vitamin D
2 Forms of Vitamin D
Vitamin D3 - cholecalciferol, made form skin after exposure to UV light
Vitamin D2 - ergocalciferol, comes from plant sterols, primary dietary source
Vitamin D analogs are used in…
patients with later stages of CKD or kidney failure to increase calcium absorption and inhibit PTH secretion
Vitamin D analogs….
Calcitriol (Rocaltrol)
Calcifediol (Rayaldee)
Doxercalciferol (Hectoral)
Paricalcitol (Zemplar)
Vitamin D analog dosing….
Taken daily, or 3X week if dialysis
Vitamin D analog info
SE: Hypercalcemia, hyperphosphatemia, N/V/D
Monitoring: Ca, PTH, PO4
Take w/ food to decrease stomach upset
Calcimimetics…..
Cinacalcet (Sensipar)
Etelcalcetide (Parsabiv)
decreases PTH, Ca, PO4 by acting on parathyroid gland
Cinacalcet (Sensipar) info
Dose: Daily w/ food
CI: Hypocalcemia
Warning: caution pt hx seizures
SE: Hypocalcemia, N/V/D, laundry list
Monitoring: Ca, PTH, PO4
Etelcalcetide (Parsabiv) info
Dose: IV 3X per week
Warnings: Hypoclacemia, GI bleed, worsening HF
SE: Muscle spasms, parathesia, N/V/D
Monitor: Ca, PO4, PTH
Erythropoiesis Stimulating Agents (ESAs)
Epoetin alfa (Procrit, Epogen, Retcrit)
Darbepoetin alfa (Aranesp) = longer acting
ESA risks
elevated blood pressure & thrombosis
When should ESA be used?
When hemoglobin is < 10g/dL, and dose should be held/d’ced if > 11 g/dL due to increase risk of thrombosis
ESAs are only effective if….
adequate iron is available
Iron levels have to be appropriate
Hyperkalemia is…
potassium levels > 5.3/5.5
normal range is 3.5 - 5
Drugs that increase renal potassium excretion?
aldosterone
diuretics (Loops> thiazides)
Common cause of Hyperkalemia?
decreased renal excretion due to kidney failure
diabetes patients at higher risk
Symptoms of elevated potassium levels?
Muscle weakness
bradycardia
fatal arrhythmias
ECG monitoring if potassium high/abnormal HR/Rhythm
Key Drugs that raise potassium levels
ACEi
Aldosterone receptor antagonists
ALiskiren
ARBs
Canagliflozin
Dorspirenone- containing COCs
Potassium containing IV fluids
Potassium supplements
Bactrim
Transplant drugs (Cyclosporine, everolimus, tacrolimus)
Treatment of Hyperkalemia
All potassium sources have to be Dc’d
if severe, urgent need to stabilize myocardial cells w/ Calcium gluconate (preferred) or calcium chloride
drugs used for stabilization dont lower total body calcium, that takes longer
Sodium polystyrene sulfonate (SPS) info
used for txm of hyperkalemia,
Dose: 1-4 times a day
Warnings: GI necrosis, inc w/ sorbitol admin so dont use together
Notes: Dont mix w/ fruit juices containing K
Patiromer (Veltassa) info
Dose: daily, max of 25.2 grams
Warmings: bind oral drugs…space by 3hrs before/after, hypomagnesemia
SE: constipation
Notes: Delayed onset of action
Sodium zirconium cyclosilicate (Lokelma) info
Dose: TID up to 48hrs
Warnings: can bind oral drugs….space by 2hrs before/after
Notes: preferred binder due to fast onset
Drugs used to replace bicarbonate….
sodium bicarbonate
Sodium citrate/citric acid solution
Monitor sodium levels in both
2 types of dialysis
Hemodialysis (HD) - couple times a week, hook em up to the machine
Peritoneal dialysis (PD) - pump stuff in, let it sit and pump it out, daily, done at home
If a medication is removed during dialysis, then it must be given….
after dialysis or may require supplemental dose
