CKD Flashcards
What are 3 characteristics of acute kidney disease?
(1) rapid loss of kidney function (w/in hours to days)
(2) commonly reversible (3) usually caused by dehydration, blood loss, medication, IV contrast, obstruction
What are 3 characteristics of chronic kidney disease?
(1) progressive loss of renal function that persists for >3 months
(2) commonly irreversible (3) usually caused by long-term diseases such as DM, HTN
What are 4 major functions of the kidneys?
(1) regulation of water, minerals, and acid-base status
(2) removal of metabolic waste products from the blood and their excretion in the urine (urea)
(3) removal of foreign chemicals from the blood and their excretion in the urine
(4) secretion of hormones- erythropoietin, renin, Vit D
A WET BED: acid-base, water balance, electrolyte balance, toxin filtration and excretion, BP, erythropoietin, Vit. D
What are the 4 major renal processes?
(1) glomerular filtration
(2) tubular reabsorption (a passive process)
(3) tubular secretion (an active process)
(4) excretion
What is CKD by definition?
GFR <60 mL/min for > 3 months
What is the pathophysiology of CKD?
Underlying etiology and nephron injury→ loss of functioning units→ hyperfiltration (to compensate for loss of functioning units and maintain GFR) → glomerular capillary HTN (b/c of hyperfiltration) → hypertrophy of remaining viable nephrons→ sclerosis and loss of remaining nephrons
What does RAAS and AII activation lead to?
Microalbuminuria/proteinuria (pore size altered by AII→ inc protein leak across glomerular basement membrane→ inc in glomerular permeability and excessive protein filtration→ microalbuminuria/proteinuria)
What is GFR?
A measure of how well the kidneys are removing wastes and excess fluid from the blood
What is a normal value for GFR, a value indicating kidneys aren’t working properly, and a value indicating tx for kidney failure is needed?
Normal: 90+, not working properly: <60, kidney failure tx: <15
What is azotemia?
The accumulation of urea and other nitrogenous compounds and toxins caused by the decline in renal function (not the same thing as uremic)
As kidney function decreases, creatinine level ____.
rises
As kidney function decreases, the BUN level ____.
rises
What does a 24 hour urine test compare?
The urine creatinine to the blood creatinine to show how much blood the kidneys are filtering out each minute
What are 7 complications of progressive CKD?
1) anemia
2) metabolic acidosis
3) dec in Vit. D and Ca+, inc. in phosphorus
4) volume overload
5) hyperkalemia
6) uremia
7) cardiovascular consequences
What would you expect to see in urine in nephrotic syndrome?
heavy proteinuria
What would you expect to see in urine in glomerulonephritis?
RBC casts
What would you expect to see in urine in acute tubular necrosis?
pigmented granular casts
What would you expect to see in urine in interstitial nephritis?
WBC casts
What would you expect to see in urine in dehydration (no intrinsic kidney disease)?
hyaline casts
What is hematuria (to dx it, not that it is blood in the urine)?
> 3 RBCs/high-power field on at least 2 occasions
What does anemia occur secondary to?
Dec production of EPO by the kidney
What does metabolic acidosis occur secondary to?
Dec bicarb reabsorption and generation by kidneys
What 2 things are elevated and used as surrogate markers for toxins?
Urea and creatinine
What are 2 big risk factors for developing CKD?
1) DM
2) HTN
What is the GFR in stage 1 CKD?
> /= 90
What is the GFR in stage 2 CKD?
60-89
What is the GFR in stage 3 CKD?
30-59
What is the GFR in stage 4 CKD?
15-29
What is the GFR in stage 5 CKD?
<15
What are 4 findings of CKD stage 4?
(1) difficult to control HTN (2) difficult to control edema
(3) hyperkalemia
(4) uremia
What are the first and second leading causes of ESRD (end-stage renal disease) and what condition do each of them lead to?
Leading: DM→ diabetic glomerular disease, diabetic nephropathy
Second: HTN→ hypertensive nephropathy
What is your target in BP control of pts w/DM?
<130/80
What are 3 ways DM contributes to CKD?
(1) damages vessels in the kidney
(2) elevated blood glucose rises beyond kidney’s capacity to reabsorb glucose
(3) glucose remains diluted in the fluid, raising its osmotic pressure and causing more water to be carried out, inc urine volume
What is the first sign of diabetic nephropathy and the most common comorbidity?
First sign: microalbuminuria
most common comorbidity: HTN
What are the 2 tx of diabetic nephropathy?
ACEI/ARBs and diuretics
What are 3 tx of hypertension?
(1) salt and water restriction (2) weight loss (3) pharm therapies
What is the goal of hypertension tx?
Halt progression to hypertensive nephropathy
What is your target in BP control of pts with hypertensive nephropathy?
<140/90
When do they recommend using ACEIs/ARBs in tx of hypertensive nephropathy and CKD?
CKD stages 1-3 and pts w/proteinuria
When tx hypertensive nephropathy w/ACEIs/ARBs what is an indication to d/c them?
If creatinine levels continue to rise instead of stabilizing after initial rise
What are 5 indications to refer to a nephrologist?
(1) GFR < 30 mL/min (CKD stages 4 and 5)
(2) rapidly progressive CKD
(3) poorly controlled HTN despite 4 agents
(4) rare or genetic cause of CKD
(5) suspected renal artery stenosis
What is dialysis?
Process for removing waste and excess water from the blood- used as an artificial replacement until renal transplant or supportive measure
What is hemodialysis?
Diffusion of solutes across a semipermeable membrane, where pts blood is pumped through the blood compartment in countercurrent direction of dialysate in dialyzer exposing it to a semipermeable membrane→ water and wastes move b/w blood and dialysis fluids and then the cleansed blood is returned via the circuit back to the body
What is the indication for kidney transplantation?
ESRD regardless of primary cause (GFR <15 mL/min)
What pt group is eligible for a kidney-pancreas transplant?
Type 1 diabetes
