CKD - Exam 2 Flashcards
what are the 2 most important contributors to CKD?
DM and HTN
how fast is kidney fxn lost in acute kidney disease
rapid loss of kidney fxn (hours to days)
is acute kidney disease reversible?
yes, acute kidney disease is reversible
what is acute kidney disease caused by?
dehydration, blood loss, medication, IV contrast, obstruction (I.e. enlarged prostate -> no urine output -> AKI)
how fast is kidney fxn lost in chronic kidney disease?
Progressive loss of renal function that persists for more than 3 months
is chronic kidney disease reversible?
no, CKD is irreversible
what is CKD caused by?
long term diseases
-DM and HTN
what is the fxn of the kidney?
- Regulation of water, minerals and acid-base status
- Removal of metabolic waste products from the blood and excretes them in urine (kidneys excrete urea-> nitrogenous waste)
- Removal of foreign chemicals from blood and excretes them in urine
-Secretion of hormones
(EPO, renin, Vit D)
what is the mnemonic for kidney fxn?
A WET BED
Acid base, water balance, electrolytes, toxin excretion, BP, EPO, Vit D
where does filtration occur in the kidney
at the glomerulus
what is the individual unit of the kidney?
nephron
what is the ultimate measure of kidney fxn?
GFR
where does reabsorption occur in the kidney?
in proximal/distal tubule and loop of henle
ALL DONE PASSIVELY
what is the secretion fxn of the kidney?
actively pumping K, H, and urea back into tubule to be excreted
in kidney failure, what happens to the secretion fxn? leads to what?
build up of K, H, and urea in the body
leads to metabolic acidosis and encephalopathy
where does excretion occur in the kidney?
collecting duct
what is the GFR for CKD?
GFR < 60 mL/min for more than 3 months
what is there a persistence of in CKD?
proteinuria, hematuria, or abnormal urinary sediment (casts)
CKD definition?
- GFR <60 mL/min for more than 3 months
- Persistence of proteinuria, hematuria, or abnormal urinary sediment
- Progressive nephrosclerosis (irreversible reduction in nephron number)
CKD results in the inability to maintain what?
A WET BED:
Acid-base balance (ex: Chronic hyperkalemia)
Fluid and electrolyte balance (ex: Edema)
Excretion of nitrogenous wastes (ex: Uremic encephalopathy)
what is the basic pathophysiology of CKD?
nephron damage -> hyperfiltration -> hypertrophy of remaining nephrons b/c want to maintain GFR -> glomerular capillary HTN -> pressure stretches capillary and causes glomerular injury -> RAAS and angio 2 activated -> pore size altered by angio 2 -> increases protein leak across glomerular basement membrane -> excessive protein filtration -> microalbuminuria/proteinuria
what contributes to progressive kidney damage?
excess protein in the urine (albuminuria/proteinuria) - clog up tubules -> inflammation -> scarring
what are the pro-inflammatory mediators for CKD?
angio 2 and aldosterone
how do angio 2 and aldosterone affect the kidney?
they are directly inflammatory to the kidney -> cause even more damage
cause glomerulosclerosis and tubulointerstitial fibrosis which promotes CKD
what does GFR measure?
how well the kidneys are removing wastes and excess fluid from the blood
how is GFR calculated?
from the serum creatinine using
-age, weight, gender, body size
what is Creatinine?
muscle breakdown product that goes thru the kidney untouched
surrogate marker to assess filtration rate
what is a surrogate marker to assess filtration rate?
Cr
GFR will go up with?
age and weight
-use ideal body weight (muscle)
normal GFR?
90 or above
GFR < 60 means?
sign that kidneys not working properly
GFR <15 means?
indicates treatment plan for kidney failure (dialysis or transplant) is needed
ESRD
when do pts with CKD start to develop sx’s?
not until stage 3 or 4
CKD sx’s
anemia (not producing as much EPO)
fatigue/weakness
decreased appetite with progressive malnutrition
stage 5 CKD sx’s
- N/V
- Decreased mental sharpness/encephalopathy
- Muscle twitches and cramps
- Swelling of feet and ankles
- Puritis
clinical manifestations of advanced stages of CKD?
Uremic syndrome
what is uremic syndrome?
symptomatic manifestations associated with azotemia
what is azotemia?
the accumulation of urea and other nitrogenous compounds and toxins caused by the decline in renal fxn
increase in Cr and BUN but NO SX’S
do you have sx’s in azotemia? what increases in azotemia?
NO!!! but have increase in Cr and BUN
difference b/w azotemia and uremic syndrome?
azotemia has no sx’s associated with increase in Cr and BUN
Uremic syndrome has sx’s
high end of normal for BUN?
20
if pts have super high BUN what can you smell? what about their skin?
the pee -> uremic factor
have uremic frost -. sweat out urea -> water evaporates -> dry leathery skin
pts with uremic syndrome are usually on what?
dialysis or almost on it
what are the complications of progressive CKD?
Anemia (b/c of less EPO), Metabolic acidosis
Derangements in Vit D, Ca2+ and Ph metabolism -> weak bones -> FRACTURE risk
Volume overload (not just edema, can also look like CHF)
Hyperkalemia (arrhythmias- can be one of the most common causes of MI)
Uremia
CV complications (HTN, atherosclerosis, valvular stenosis, CHF)
what must you consider when approaching a pt with new renal dysfunction?
pre-renal, renal, and post-renal etiologies
what will GFR and Cr be in CKD?
Cr will be UP and GFR will be DOWN
what labs do you run for pt with new renal dysfunction?
serum Cr, urine dipstick, microscopy, and spot protein
urinalysis
what imaging do you start with for pt with new renal dysfunction?
renal U/S
what do you do after renal U/S?
Ct without contrast
when do a urinalysis for pt with renal dysfunction, what are you looking for?
casts in the urine
what must you consider for pt with new renal dysfunction?
multiple myeloma - especially if have new renal insufficiency and new anemia, blood in urine, but no RBCs
how do you check for MM in pt with new renal dysfunction?
serum protein electrophoresis, urine protein electrophoresis
abnormal labs in CKD
elevated BUN, elevated Cr, hyperkalemia, hyperphosphatemia, hypocalcemia, proteinuria, RBC/cast in urine, WBC/cast in urine
what do normal levels of Cr depend on?
age, race, body/muscle size
what are early signs of kidney dysfunction in men and women for Cr?
Cr > 1.2 in women
Cr > 1.4 in men
as kidney fxn decreases, Cr ____
increases (Cr not getting filtered at the same rate b/c of kidney dysfunction)
what is the measure of BUN?
measure of nitrogen in your blood that comes from the waste product urea
when is urea made?
when protein is broken down in your body
normal BUN?
7-20
as kidney function decreases, BUN ___
increases (urea isn’t being filtered out)
what does a 24hr urine test compare? what does it show?
urine Cr to the blood Cr
shows how much blood the kidneys are filtering out each minute
what does a urinalysis test for?
tests for protein (albumin) in the urine
in nephrotic syndrome, what urine sediment is seen?
heavy proteinuria
in glomerulonephritis, what urine sediment is seen?
RBC casts
in acute tubular necrosis, what urine sediment is seen?
pigmented granular casts
in interstitial nephritis, what urine sediment is seen?
WBC casts
in dehydration, what urine sediment is seen?
hyaline casts
when does microalbuminuria occur?
when the kidney leaks small amounts of albumin into the urine (have a leaky glomerulus)
what is the preferred test for microalbuminuria?
24hr urine collection
-positive for microalbuminuria = albumin 30-300mg/24hrs
when do you see macroalbuminuria in CKD?
more advanced disease
test for macroalbuminuria?
spot sample -> > 300mg/L
24hr urine collection -> > 300mg/day
what is hematuria?
> 3 RBCs per high power field on at least 2 occasions
conditions that hematuria?
not only in CKD
-urologic malignancy, UTI, interstitial nephritis, AAA
as protein goes up in the urine, what does this portray?
worsening kidney function (should not have protein in the urine)
> 150-160 mg/24 hrs of protein in urine is what?
abnormal
what level of proteinuria signifies underlying kidney abnormality?
> 1-2 g/24hr
-usually glomerular problem
what level of proteinuria signifies nephrotic syndrome?
> 3.5 g/24hr
what is a normal spot urine?
< 0.2
spot urine is equivalent to what?
24hr urine for urine protein/urine Cr ratio
normal values spot urine in men and women
men < 1.1
women < 1.6
how does anemia occur in CKD?
secondary to decreased production of EPO by the kidney
what should be provided to pts with CKD and Hgb < 10mg/dL
EPO stimulating agents (Procrit)
goal of Hgb with EPO stimulating agents?
goal is 11-12 mg/dL
-higher goals are associated with increased mortality
how does metabolic acidosis occur in CKD?
Secondary to decreased bicarb reabsorption and generation by the kidneys
-can’t secrete H+ and reabsorb bicarb
how do you treat metabolic acidosis in CKD? when do you treat?
Treat with bicarb supplementation when bicarb <18 mg/dL (target is 22 mg/dL)
why do you get vitamin d deficiency with CKD?
b/c kidney is responsible for activating vitamin D, but with CKD it can’t
what vitamin D do you measure?
25-OH vitamin D (storage form)
normal vitamin D level?
> 30mg/mL
why do you get bone disease in CKD?
Secondary to abnormalities in the complex interaction between Vit D, phosphorous, Ca and PTH
bone disease in CKD results in what? what do they lead to?
Results in either:
-Excessive bone resorption (osteilitis fibrosa cystica)
-State of bone quiescence (adynamic bone disease)
Both lead to increased risk of fractures
what is difficult to control in CKD stage 4 (GFR 15-29 ml/min)?
HTN (requires large doses of loop diuretics) and edema
how to treat hyperkalemia in CKD?
kayexalate
uremia in what stage of CKD?
CKD stage 4 (GFR 15-29 ml/min)
if have CKD stage 4 or 5, who must you be referred to?
nephrologist
if in CKD stage 5 (GFR < 15 ml/min), what do you need?
renal transplant or discussions regarding end of life
once on dialysis, what is the mortality rate within 5 years?
> 50%
CKD is a significant risk factor for what?
for CV disease (most die from complications of CV disease)
most common causes of ESRD?
*Diabetic glomerular disease
HTN nephropathy
- Primary glomerulopathy with HTN
- Vascular and ischemic renal disease
what is the leading cause of ESRD?
DM
what reduces progression of kidney disease when have DM?
intensive insulin therapy to maintain HbA1c < 7%
what should pts BP be if DM and have CKD?
<130/80
-lowering the BP delays the onset of microalbuminuria by decreasing glomerular HTN
first sign of diabetic nephropathy? important to do what test?
microalbuminuria
-doing spot urine checks is really important
most common comorbidity of diabetic nephropathy?
HTN
tx for diabetic nephropathy?
- ACE/ARBs (renal protective properties)
- Diuretic (addition of a second agent to aid in BP control)
- Also need tight glycemic control, weight loss, diet, exercise
what is the 2nd leading cause of ESRD?
HTN - accelerates CKD
controlling BP, slows down what?
the decline in GFR
inhibiting RAAS is effective in what?
lowering BP and reducing microalbuminuria
goal of therapy for HTN in terms of CKD?
halt progression to hypertensive nephropathy
hypertensive nephropathy develops in what pts?
pts with protein uric and HTN
BP goals in a pt with CKD and HTN?
<140/90
guidelines for tx of hypertensive nephropathy, advise caution with use of what?
use of ACE/ARB in the presence of renal impairment
Expect worsening Cr up to 30% or reduction of GFR 20% from baseline
-if values stabilized after initial rise, then safe to continue use
-If values continue to rise, then D/C ACE/ARBs and consult nephrologist
when should you D/C ACE/ARBs and consult nephrologist when treating hypertensive nephropathy?
if Cr levels continue to rise and GFR continues to decline
at what level of K do you stop K-sparing drugs and what other drugs do you reduce dose of?
hyperkalemia >6
reduce loop diuretic dosage (they lower the flow)
when treating hypertensive nephropathy what must you check before starting meds and after starting meds?
Cr, K, and GFR (and any time there is a dose change)
if pt has CHF, what meds MUST they be on?
ACE and ARBs
how do you ACEs and ARBs help with CHF?
- Reduce the glomerular permeability barrier to proteins
- Limit proteinuria and filtered protein-dependent inflammatory signals
- Decrease glomerular intra capillary pressure
CKD is a risk factor for what?
CV disease
what is independently associated with an increase in CV mortality?
reduced GFR and proteinuria
elevated BP leads to what?
to damage of blood vessels within kidney and throughout body -> Increase CKD
what is the primary prevention for CKD?
weight loss, exercise, BP control, glucose control
treat underlying ___ for CKD
Treat underlying disorder
tx for CKD (stage 5)
dialysis - hemodialysis and peritoneal dialysis
renal transplant
dialysis is considered what?
a holding measure until renal transplant can be done
or a supportive measure in those with AKI where transplant is unlikely/unnecessary
methods for hemodialysis
AV fistula/graft
need a flow rate b/w an artery and a vein
what is bad about synthetic grafts for hemodialysis?
clot more and get infected more
dialysis catheter/port is used in who?
people who need dialysis acutely -> NOT chronically
peritoneal dialysis is less efficient than ____
hemodialysis
when does someone need a kidney transplant? GFR?
ESRD regardless of primary cause (GFR < 15 ml/min)
can also do preemptive transplant before dialysis is needed in those with CKD
majority of renal transplant recipients are on what at time of transplant?
dialysis
where is the new kidney put into the body?
into lower abdomen
do you still need dialysis if got kidney transplant?
NO!!!
what is a kidney pancreas transplant?
Operation to place both a kidney and pancreas at same time into someone with kidney failure secondary to Type 1 Diabetes -> Cures them of DM
who is NOT a candidate for kidney pancreas transplant?
type 2 DM b/c already have working pancreas just can’t use insulin properly
when do you refer a pt to a nephrologist?
- GFR <30 ml/min í CKD stages 4 and 5
- Rapidly progressing CKD
- Poorly controlled HTN despite 4 agents
- Rare or genetic causes of CKD (polycystic kidney disease)
- Suspected renal artery stenosis
