Renal Dx & Dosing Consideration Flashcards
List drugs usually removed in dialysis?
Amikacin
Cefazolin, Cefepime, Cephalexin
Lithium
Meropenem
Tobramycin
List factors that affect drug removal during dialysis
Molecular size
Protein binding
Vol of distribution (Vd)
Plasma clearance
Dialysis membrane
What’s used to gauge the severity of kidney damage in pts with kidney or nephropathy?
Albumin in urine (micro or macroalbuminuria)
What’s used as a marker of renal fxn in various estimating equations?
Conc of creatinine in the serum
What does Blood Urea Nitrogen (BUN) measure?
Amt of nitrogen that comes from set product urea
BUN increases with renal impairment (not used independently)
Role of loop diuretics?
Loop diuretics inhibit the Na-K pump in the ascending limb of the loop of Henle
Common drugs that req dosage reductions or increased dosing intervals with decreased renal fxn?
Acyclovir, Valacyclovir
Allopurinol, Amantadine, Amphotericin, Aminoglycosides, Azoles,
Antiarrhythmics, Anti-TB, Azteronam
Beta-lactam antibiotics
Colchicine, Cyclosporine
Dabigatran
Famotidine, ranitidine
Gabapentin, pregabalin
Ganciclovir, Valganciclovir
NRTIs (didanosine, Lamivudine, Stavudine, Tenofovir, zidovudine)
LMWH (Enoxaparin)
Macrolides (Clarithromycin, erythromycin)
Maraviroc, Metoclopramide, Morphine and codeine
Penicillin
Quinolone antibiotics (Cipro, Levo)
Statins
SMX/TMP
Tramadol
Vancomycin
Venlafaxine, Desvenlafaxine
Zoledronic acid
Role of Thiazide diuretics?
Inhibitors Na-Cl pump in distal tubule
Why does long-term use of thiazides have a protective effect on bone?
Thiazides increase Ca absorption by affecting Ca pump in distal convoluted tubul
Primary fxn of aldosterone?
Increase Na and water retention and to lower K
T4 aldosterone antagonists (Spironolactone or Eplerenone) increases serum K
What’s the normal range of serum creatinine?
0.6 to 1.2 mg/dL
Creatinine above this range indicate kidneys aren’t functioning properly
Common drugs that shouldn’t be used in severe renal impairment?
Avanafil
Bisphosphonates
Chlorpromazine, Cidofovir
Dabigatran, Dofetilide, Duloxetine
Fondaparinux, Foscarnet
Glyburide
Lithium
Meperidine, Metformin
Nitrofurantoin, NSAIDs
Potassium-sparing diuretics
Ribavirin, Rivaroxaban
Sotalol (Betapace AF)
Tadalafil, Tenofovir, Tramadol ER
Voriconazole IV
Know Cockcroft-Gault equation
Ok
How are drug regimens modified in renal impairment?
Either by reducing the dose and/or extending the dosing interval
List risk factors for progression of CKD?
Uncontrolled HTN
DM
Proteinuria
Role of ACE-I or ARBs in nephropathy?
Strong evidence to support use of ACE-I or ARBs to prevent progression of nephropathy in DM and non-DM pts with Proteinuria
ACE-I or ARBs and serum creatinine?
ACE-I or ARBs can cause a 30% rise in serum creatinine during initiation of therapy
This rise is generally acceptable and NOT a reason to stop therapy
Recommended monitoring (1-2 wks after initiation) of ACE-I or ARBs?
Serum creatinine
Potassium
Primary tx of secondary Hyperphosphatemia?
Restrict dietary phosphorus
Such as Diary pdts, dark colored sodas, chocolate and nuts
Pharmacologic tx of secondary Hyperphosphatemia?
Aluminum-based agents (AlternaGel, others) - short-term use only as
Al can accumulate in CKD
Ca-based agents (calcium acetate & carbonate) - many CKD pts are on Vit. D, which raises Ca levels and can’t tolerate additional Ca
Aluminum-free, Ca-free agents. (Most expensive)
MOA of phosphate binders?
They bind meal-time phosphate in the gut that’s coming from the diet
(If a dose is missed & food is absorbed, there’s no pork t taking it later or doubling up on next dose)
Role of Aluminum-based pdt (Aluminum hydroxide - AlternaGel, Amphojel, others) in Hyperphosphatemia?
Most potent phosphate binder, but use limited to 4 wks due to risk of accumulation
What’s first-line therapy for Hyperphosphatemia of CKD?
Calcium-based pdts e.g.
Calcium acetate (PhosLo, Phoslyra, others)
Calcium carbonate (Tums, Store brands)
Agents under Aluminum-free, Ca-free agent?
Lanthanum carbonate (Fosrenol)
Howz Lanthanum carbonate (Fosrenol): Al-free, Ca-free taken?
Chewable…must chew thoroughly
Role of Sevelamer in Hyperphosphatemia?
Non-Ca, Non-Al based phosphate binder that’s NOT systemically absorbed
Also has benefit of lowering TC & LDL by 15-30%
Agents under Sevelamer? Which may be preferred?
Sevelamer carbonate (Renvela) - preferred
Sevelamer hydrochloride (Renagel)
Tx of Vit. D deficiency and secondary Hyperparathyroidism?
After controlling Hyperphosphatemia, elevations in PTH are treated primarily thru the use of Vit. D
Types of Vit. D?
Vit. D3 or Cholecalciferol (synthesized in skin after exposure to ultraviolet light)
Vit. D2 or Ergocalciferol (produced from plant sterols and is the primary dietary source of Vit. D)
What’s used in pts with CKD to increase Ca absorption from gut, raise serum Ca conc and inhibit PTH secretion?
Calcitriol (Rocaltrol) - active form of Vit. D3
List agents for tx of secondary Hyperparathyroidism
Vit. D analogs - increase intestinal absorption of Ca + provide negative feedback to parathyroid gland
Calcitriol (Rocaltrol, Calcijex)
Doxercalciferol (Hectorol)
Paricalcitol (Zemplar)
Dose of Calcitriol (Rocaltrol, Calcijex) - Vit. D analog - used in CKD?
Calcitriol 0.25 mcg PO 3 times weekly to daily
Dose of Calcitriol (Rocaltrol, Calcijex) - Vit. D analog - used in Dialysis?
0.5 - 1 mcg PO daily
Or
0.5 - 4 mcg IV 3 x weekly
Dose of Doxercalciferol (Hectorol) - Vit. D analog - used in CKD?
1 mcg PO 3 x weekly to daily
Dose of Doxercalciferol (Hectorol) - Vit. D analog - used in Dialysis?
2.5 - 10 mcg PO 3 x weekly
Or
1 - 4 mcg IV 3 x weekly
Dose of Paricalcitrol (Zemplar) - Vit. D analog - used in CKD?
1 mcg PO 3 x weekly to daily
Dose of Paricalcitrol (Zemplar) - Vit. D analog - used in Dialysis?
2.8 - 7 mcg IV 3 x weekly
Or
2 - 4 mcg PO 3 x weekly
CI to Vit. D analogs?
Hypercalcemia
Vit. D toxicity
MOA of Calcimimetic
Increased sensitivity of Ca-sensing receptor on the parathyroid gland, => reduces PTH, Ca, Phos and prevent progressive bone dx
Agent under Calcimimetic?
Cinacalcet (Sensipar)
CI to Cinacalcet (Sensipar) use?
Hypocalcemia
Tx of Vit. D deficiency when serum 25(OH) Vit. D level < 5 ng/mL?
Ergocalciferol 50,000 units PO every week x 12 wks
Then 50,000 units PO monthly
Total duration = 6 months
Tx of Vit. D deficiency when serum 25(OH) Vit. D level 5 - 15 ng/mL?
Ergocalciferol 50,000 units PO every week x 4 wks
Then 50,000 units PO monthly
Total duration = 6 months
Tx of Vit. D deficiency when serum 25(OH) Vit. D level 16 - 30 ng/mL?
Ergocalciferol 50,000 units PO monthly
Total duration = 6 months
Value of normal potassium level?
3.5 - 5 mEq/L
Whats hyperkalemia (high potassium)?
K level > 5 mEq/L
What’s the most abundant intracellular cation?
K
What increases potassium excretion?
Aldosterone
Diuretics (strongly by loops, weakly by thiazides)
How does the body deal with acute rise in K?
Body releases INSULIN, which would cause K to shift into cells
Whats the most common cause of hyperkalemia?
Decreased renal excretion due to renal failure
List drugs that raise K
K-sparing diuretics
ACEIs
ARBs
NSAIDs
OCPs that contain Drospirenone (YAZ, etc)
Cyclosporine
Tacrolimus
Heparin
Canagliflozin
Pentamadine
SMX/TMP
K supplements
K present in IV fluids including TPN
Whys a DM pt at risk of hyperkalemia?
They have insulin deficiency, which reduce ability to shift K into cells (role of insulin on k)
Diets are often high in Na and low in K + are on ACEIs or ARBs
Role of IV Ca in hyperkalemia?
Stabilizes the cardiac tissue (doesn’t lower K, but prevents cardiotoxicity that may occur from hyperkalemia)
How do u enhance K uptake into cells in hyperkalemia?
Give Glucose (to stimulate insulin secretion) + Insulin ( given with glucose to prevent hypoglycemia)
Or
Beta-agonist e.g. Nebulized Albuterol
Consider use of cation exchange resin, sodium polystyrene sulfonate (Kayexelate$
How’s SPS (Kayexelate) given in hyperkalemia?
PO or rectally
What route of SPS (Kayexelate) is preferred for high (emergency) tx of hyperkalemia?
Rectal
SEs of SPS (Kayexelate)?
Reduced appetite
N/V
Constipation (less commonly diarrhea)
When’s tx of metabolic acidosis initiated?
Serum bicarbonate conc < 22 mEq/L
List agents used to replace bicarbonate in metabolic acidosis of CKD?
Sodium bicarbonate tabs, granules, powder
Sodium citrate/Citric acid (Bicitra, Cytra-2, Oracit, Shohl’s soln)