CKD

Question 1

definition of CKD

Answer 1

GFR<60 for at least 3 months
+/- kidney damage

Question 2

what stage of CKD do symptoms begin to present? and what are the most common early symptoms?

Answer 2

they are beginning in G3a/b but they may go unnoticed: tired, nocturia, mild anemia
Stage G4:
nocturia, fatigue, cold intolerance, abnormal taste, anorexia, increased Phos, decreased Ca, increased K, metabolic acidosis, worsening anemia, inability to adjust to changes in Na intake

Question 3

protein recommendations for CKD 3-5 without DM?

Answer 3

restrict protein intake to 0.55-0.6 g/kg/day. can supplement with amino acid analogs

Question 4

protein recommendations for CKD 3-5 WITH DM?

Answer 4

restrict protein intake to 0.6-0.8 g/kg/day

Question 5

protein recommendations for CKD on dialysis?

Answer 5

(with or without DM)
restrict protein intake to 1-1.2 g/kg/day

Question 6

what are some pharm agents recommended to decrease proteinuria?

Answer 6

RAAS inhibitors
SGLT2 inhibitors
nonsteroidal MRA finerenone

Question 7

when are RAAS inhibitors (ACE/ARB) initiated/ discontinued?

Answer 7

first line for albumin category A2 (30-300)
regardless of GFR category
titrate to maximum tolerated dose and CONTINUE AT THE MAX DOSE: IF HYPERKALEMIA DEVELOPS CONTINUE THE RAAS INHIBITOR AND TREAT HYPERKALEMIA
don’t discontinue until >30% decrease in GFR, or when dialysis is initiated.
monitor SCr, K every 2-4 weeks

Question 8

when are SGLT2 inhibitors initiated/discontinued

Answer 8

1st line for DM2 (eGFR at least 20)
if eGFR falls below 20, continue SGLT2 if it was already initiated.
discontinue when dialysis is initiated.

Question 9

when is finerenone initiated

Answer 9

T2DM with:
-eGFR >25
-normal serum potassium
-albuminuria (>30) despite max dose of RAAS

(role in non-DM CKD unknown)

Question 10

role of SGLT-2 inhibitors in non-DM CKD?

Answer 10

heart failure
ACR>200

Question 11

what causes hypertension associated with CKD?

Answer 11

fluid overload and RAAS hyperactivity (adaptive responses)

Question 12

goal BP in CKD

Answer 12

SBP<120
don’t care about diastolic

Question 13

treatment of hypertension in CKD

Answer 13

1st line: RAAS inhibitor
if BP not at goal: anything that achieves BP goal, any antihypertensive

Question 14

what are the adaptive responses of CKD that cause fluid imbalance by impaired sodium/water balance??

Answer 14

increase in atrial natriuretic peptide (ANP)
increased fractional excretion of sodium (FENa) of functioning nephrons (caused by ANP)
osmotic diuresis: increased solute load in functioning neurons, obligatory water losses that presents as nocturia. kidney unable to concentrate urine

net effect of all this: increased total body Na
(not meaning hypernatremia; it gets diluted out w/ water)

Question 15

what is the clinical presentation of fluid imbalance in CKD?

Answer 15

nocturia
decrease total sodium excretion
volume overload
increased BP

Question 16

pharmacologic therapy for fluid imbalance in CKD and what to do when there is tolerance

Answer 16

first line: loop diuretics (start low and titrate up)
as CKD progresses there will be diuretic tolerance: overall diuresis decreases with long term use. management: add on therapy for synergistic effect with thiazide diuretics (usually don’t work as a single agent when GFR<30, but as an add on they work)
higher doses required to achieve desired effect

Question 17

what causes hyperkalemia associated with CKD

Answer 17

decreased renal potassium excretion: decreased glomerular filtration, decreased potassium secretion from distal tubules

Question 18

when does hyperkalemia present in CKD

Answer 18

when GFR<20

Question 19

goal potassium in late CKD

Answer 19

4.5-5.5

Question 20

treatment of hyperkalemia in CKD

Answer 20

nonpharm: dietary restriction (cutting back on tomatoes, bananas, potatoes)
severe hyperkalemia: dialysis

pharmacologic:
Use medications that can increase potassium with CAUTION:
-ACE inhibitors
-K-sparing diuretics
-(even beta blockers can inhibit intracellular sodium potassium pump)

Increase potassium excretion with the following agents:
-loop diuretics (kill 2 birds with one stone because they are probably fluid overloaded by this point)
-potassium binders: patiromer, sodium zirconium cyclosilicate, odium piolystyrene sulfonate)
-fludrocortisone

Question 21

patiromer (Veltessa) pros/cons

Answer 21

onset: 7 hours, max by 48 hours– do do not use when there is acute hyperkalemia w/ EKG changes
drug interactions: separate from all other drugs by 3 hours
ADEs: diarrhea, constipation, nausea, abdominal discomfort, decreases Mg levels

Question 22

sodium zirconium cyclosilicate (Lokelma) pros/cons

Answer 22

decreases K within 1 hour, max effect in 48 hours (a little faster but still not best for EKG changes)
ADEs: edema
separate from other drugs by 2 hours

Question 23

sodium polystyrene sulfonate pros/cons

Answer 23

decreases K within 6 hours of dose
ADEs: serious rare GI effects like colon necrosis, bowel perforation
common ADEs: diarrhea, abdominal pain

Question 24

fludrocortisone pros/cons

Answer 24

onset: several days
ADEs: HTN, Edema
can be an add on to patients who have hypotension with dialysis since it causes HTN

Question 25

what causes acid/base imbalance in CKD?

Answer 25

decreased renal ammoniagenesis: decreased ammonium production, decreased elimination of acid

Question 26

what happens to the acid/base balance in stage 3 CKD

Answer 26

bicarb reabsorption is maintained
decreased ammonium production
decreased acid excretion
results in nonanionic gap metabolic acidosis

Question 27

what happens to the acid/base balance in stage 4 CKD

Answer 27

bicarb reabsorption maintained
worsening of decreased ammonium production
worsens acid excretion
accumulation of organic anions
creates anion gap metabolic acidosis
net effect: serum CO2 stabilizes as 12-18

Question 28

what are some of the consequences of metabolic acidosis in CKD

Answer 28

bone disease
fatigue
dec exercise tolerance
cardiac
hyperkalemia
etc

Question 29

treatment of acid/base in CKD

Answer 29

goal CO2 is >22 (avoid rapid changes in pH)
non pharm: increase bicarb in the dialysis solution
pharm: oral bicarb supplements

Question 30

what stage of CKD do electrolyte imbalances begin?

Answer 30

stage 4
increase in Phos, K
decrease in Ca