Chronic Kidney Disease Flashcards
CKD incidence and prevalence
-estimated 1 million pt w ERSD by 2030
Major causes of CKD
-diabetes mellitus**
-HTN**
-glomerulonephritis
CKD staging
-abnormal kidney structure
-present for >3 months
-implications for health
-look mostly at CrCl and GFR
CKD classification
-cause
-GFR (less than 90)
-albuminuria (more than 30 mg/g or 3 mg/mmol)
-5 stages (stage 1 and 2 not noticible)
GFR categories
-G1: >90
-G2: 60-89
-G3a: 45-59
G3b: 30-44
G4: 15-29
G5: <15 (ESKD)
-lower value worse
Albuminuria categories
A1: <30mg/g or <3mg/mMol
A2: 30-300 or 3-30
A3: >300 or 30
-higher value worse
Life expectancy in CKD (ESKD)
-20 y/o might make it to 40
-60 y/o might make it to 65
Estimations of kidney function
- Cockroft and Gault formula
- MDRD formula
Cockroft and Gault formula
-estimate CrCl
-most common
-accurate for pt w stable kidney function
-good predictor of GFR
-tends to overestimate renal function in kidney impairment (10% of CrCl bypasses filtration)
-used most by Rph
Modification of Diet in Renal Disease (MDRD)
-most accurate measure of GFR
-accounts for race and gender
-eGFR used for staging
-CrCl used for dosing
Cockroft and Gault formula
Men: CrCl = (140-age)IBW / (Scr*72)
-multiply by 0.85 in women
-IBW 50 or 45.5+2.3(inches over 5ft)
-use AjBW if patient is 130% of IBW
AjBW = IBW+0.4(ABW-IBW)
MORD equation
-GFR = 170 x (Scr)^-0.999 x age x (SUN)^-0.170 x Alb^0.318
multiply by 0.762 if pt is female and 1.180 if pt is black
Why is albumin in kidney a big deal
-it’s a big protein and should have been filtered earlier
-indicates problem with filter
Complications from kidney disease
-Uremia
-Fluid Retention (diuretics wont work)
-Electrolyte imbalance (put some in dialysis fluid)
-mineral and bone disorder
-anemia
-not really seen until stage 4 and 5
Uremia
-accumuulation of waste molecules in the blood
-pruritus, confusion, N/V
Uremia assessment
-increased BUN value
Uremia effects
-encephalopathy
-Uremic fetor
-pulmonary edema
-sodium retention and volume overload in heart
-anorexia, N/V, constipation metallic taste
-mineral bone disorder, rstless leg
-anemia
-uremic frost: tiny urea crystals deposit on skin
Fluid Retention complications
-water retention = edema
-BP increase
Fluid retention tx
-restricting fluids not necessary if sodium intake is controlled
-diuretics will not work if kidneys dont work
-loop diuretics +/- thiazide
Diuretic tx for fluid retention
-tx volume overload and HTN
-patient must be making some urine (functioning ish kidney)
-loops +/- thiazide
-if one loop doesnt work none will
Diuretic considerations
-thiazides ineffective at CrCl< 30
-but loops work
-furosemide bioavailabilty at 50% so oral dose can be double the IV dose
-AVOID potassium-sparing diuretics
-as renal function declines, loop dose is maximized and a thiazide can be added to overcome resistance
-consider etharynic acid if sulfa allergy concern
Tx Na imbalance
-no salt added diet
-more restricting if HTN or edema bad (less than 2g sodium, 5g NaCl)
-use saline IV solutions w CAUTION
-make pt aware of hidden high sodium foods
K imbalance tx
-restrict to 3g/day
-goal concentration 4.5-5.5 (upper range but pt less sensitive to K)
-avoid high K foods
-tx for hyperkalemia
-easy to control on dialysis
Which diuretic least likely to cause sulfa allergy
-ethacrynic acid
Oral bioavailability
-furosemide has lowere bioavailability
-may need to titrate dose
Mineral and Bone Disorder (CKD-MBD) causes
- inc phosphorus
- decreased production of active Vit D
- dec calcium
-all increase PTH production (take Ca out of bone and into blood)
Common MBD fracute
-vertebrae
Hyperphosphatemia
-normal 2.5-4.5
-excess phosphorus binds calcium
-little white deposits in blood go to soft tissue organs and blood vessels
-tx w phosphate binders
Phosphate binders
-bind dietary phosphate
=MUST TAKE W FOOD
-Ca carbonate **
-Ca actetate
-Sevelamer carbonate **
-Lanthanum carbonate
-Sucroferric oxyhydroxide
-Auryxia (anemia)
-Aluminum Hydroxide (dont use)
-Mg carbonate
Calcium Carbonate (TUMS)
-40% elemental Ca
-Ca can get absorbed into blood and bind phosphorus there = more calcium deposits
-side effects: constipation
-500mg TID wf
Max amount of Ca you can take
-1500mg/day
Calcium acetate (PhosLo)
-25% Ca
-2-3 tab TID wf
-binds 2x phosphate than tums
-may produce fewer hypercalcemic events than tums
Sevelamer Carbonate
-best but not as cheap as tums
-also decreases LDL, uric acid (good for gout)
-maybe mild tummy ache but pretty safe
Lanthanum Carbonate
-eliminated in feces
-no long term accumulation
-GI side effects
-binds phosphorus better in acidic environments (tummy)
Sucroferric Oxyhydroxide
-minimal effect on iron stores
-dark stools
Auryxia (Ferric Citrate)
-for pt on dialysis
-inc TSAT and ferritin
-inc iron (good for anemia)
-discolored feces