Lecture 3 Flashcards
Cockcroft-Gault
calculated measurement of CrCl
(M): (140 - age) x IBW in kg / 72 kg x Sir in mg/dL
(F): (CrCl Male) x 0.85
assumes stable renal function and normal mm mass
Creatinine clearance
Measured
nephrotoxic agents
should be avoided in pt’s at high risk for AKI
ahminoglycosides, amphotericin B, Radiocontrast agents, Cyclosporin/Tacrolimus, ACE inhibitors/ARBs and NSAIDs
kidney functions
excretory (fluid, electrolytes and solutes), metabolic (vit D and some drugs like insulin and B-lactams), endocrine (erythropoietin)
Diuretic classes
thiazides, carbonio anhydrase inhibitors, K sparing, osmotic, loop
important thiazide diuretics
chlorothiazide, hydrochlorothiazide, indapamide, metolazone and chlorthalidone
chlorothiazide
relative potency of 0.1, least potent
hydrochlorothiazide
relative potency of 1
indapamide
relative potency of 20, most potent, may be used if CrCl < 30
metolazone
relative potency of 10, may be used if CrCl <30
chlorothalidone
relative potency of 1
carbonic anhydrase inhibitors
limited usefulness as diuretic , open-angle glaucoma
K sparing diuretics
usually administered with K-losing thiazides (helps minimize K loss)
Na channel inhibitors (K sparing)
amiloride and triamterene
aldosterone antagonists (K sparing)
Spironolactone: CrCl 10-50 administer q24hr
CrCl < 10 avoid use
SE: gynecomastia and impotence
glycerine, isosorbide and urea
osmotic diuretic, little clinical use
loop diuretics
most potent diuretics, individualize therapy
4 agents available both PO and IV
adverse effects: ototoxicity (tinnitus, deafness, vertigo - reversible) and hyperuricemia (rarely gout) and hyperglycemia
Furosemide (Lasix)
excellent bioavailability (good oral abs) acute pulm edema: start at 40 mg IVP over 1-2 min, then 80 mg IVP if no response Metolazone (thiazide) can be added for pt's refractory to furosemide (synergistic effect) - double dose q24hr to desired response
diuretic ceiling effect
inability of drug to prod additional effects above a certain max effective dose
torsemide
preferred in its with persistence fluid retention despite high doses of other loops
urinary acidifying agent
ammonium chloride
urinary alkalinizing agent
inc elimination fo Aspirin
Na bicarb and K citrate
phosphate binders
PO4 is retained, (Ca x PO4) pdt > 40 may precipitate (metastatic calcification aka stones in tissue) need for these
first line phosphate binding agents
Ca Carbonate (Tums), Ca Acetate (PhosLo), Sevelamer HCl (Renagel) and Sevelamer Carbonate (Renvela)
second line phosphate binding agents
Lanthanum Carbonate (Fosrenol)
Ca Acetate
target serum PO4 < 6 mg/dL
mild hypercalcemia is >10.5 –> constipation, anorexia and N/V
severe hypercalcemia >12 –> delirium, stupor and coma
normal is 8.4-10.2
first line
Sevelamer (Renagel)
may red vit D, E, K and folate abs anion - exchange resin may induce metabolic acidosis in pt's on HD target PO4 level < 6 try after Ca Acetate
Na Polystyrene Sulfonate (Kayexalate)
K-binding agent
SE: hypocalcemia, hypokalemia, hypomagnesium, N/V
monitor EKG and electrolytes listed
oral Fe for CKD anemia
give 200 mg elemental Fe
titrate dose to minimize GI upset
IV Fe
Ferric Gluconate and Fe Sucrose
Ferric Pyrophosphate Citrate
water-sol complex Fe salt
added to hemodialysate sol
adv: progressive Fe accumulation doesn’t occur, red use of costly ESAs, inexpensive ($61/50 mL ampule so can tx multiple pt’s)
Epoetin Alfa (Epogen, Procrit)
Recombinant Human Erythropoietin Non Dialysis CRF dose: 75-150 units/kg/wk Dialysis CRF dose: 75 units/kg 3 x week round doses to nearest 1000 units ESA
Darbepoetin alfa
1/2 life is 3 x that of epoetin alfa
to convert from epoetin, add weekly units
ESA
tx of Benign prostatic hyperplasia
a1 antagonists or 5a-reductase inhibitors
Tamsulosin (Flomax)
adverse effects: orthostatic hypotension (16% at 0.4 mg, 19% at 0.8 mg)
5a reductase
catalyzes conversion of testosterone to DHT
type II mainly in prostate and hair follicles
