Renal Failure Flashcards
What are 4 functions of the Kidney?
maintain control of body fluid composition/volume
control over electrolyte concentrations
Acid/base balance
RBC synthesis (EPO)
Acute Renal Filure is characterized by
Rapid loss of renal fxn over days to wks
Chronic Kidney Disease is characterized by
progessive loss of fxn over several months to year where the normal kidney is replaced with intersitial fibrosis
Chronic Kidney Disease is prevalent in the ______.
Older (>65)
African Americans (4x)>Native Americans(3x)>Hispanics(2x)>whites
Male>Female
Hx of DM, HTN
What is the defnition of CKD?
kidney damage >3months with dec glomerular filtration rate (GFR)
or
GFR<60 for 3 months
What are the 5 stages of CKD and the GFR cut offs
Stage1 - Kidney damage with normal of inc GFR - >90
Stage 2 - Kidney damage with mild dec in GFR - 60-90
Stage 3 - Moderate dec in GFR - 30-60
Stage 4 - severe dec in GFR - 15-30
Stage 5 - Kidney Failure - <15 (or dialysis)
What are some causes of CKD?
1) DM
2) HTN
3) Glomerulonephritis
4) Others: UTI, PCKD, Lupus
What are some progression factors in CKD?
Proteinuria, hyperglycemia, inc BP, smoking, high protein diet
Angiotensin II causes ________ of the efferent arteriole
vasoconstriction
What happens after vasoconstriction of the efferent arteriole and the GCP and GMP size increase?
protein filtration occurs where you get protein in your urine, it is reabsorbed in renal tubules, and that casues an inflammatory cascade which included scarring of renal tubules and loss of more nephrons and eventually ESRD
what are the sxs of ESRD?
Pruritis, N/V, Bleeding
Anemia: cold intolerance, SOB, fatigue
Edema, change in urine output, “foaming” of urine
What are the two ways to estimate GFR?
1) using Scr and then calculating CrCl and correlate that to GRF
2) GRF through radioactive dyes or with inulin which is the gold standard
What is the Cockcroft-Gault equation? What is different if its a female?
(140-age)xwt / (72+Scr)
Multiply by 0.85 if a female
What is the MDRD eqution?
Modification of Diet in Renal Disease Equation
Usually only good for Caucasians and African Americans
Only used to estimate GFR, NOT used for drug dosing
How does Albuminuria/proteinuria happen?
inc glomerular capillary pressure expands the pores in the glomerular membrane and allows protein to filter through which inc protein detection in urine
What is the Normal, microalbuminuria,macroalbuminura and Nephrotic proteinuria numbers?
Protein in Urine (mg) over 24 hours
Normal 300mg/24hr
Nephrotic proteinuria >3g/24hr
When someone is diabetic how often do you monitor for proteinuria?
Type 1 DM: annually after 5yrs of diagnosis
Type II DM: annually immediately after diagnosis
What are the Dietary Protein Restrictions for pts with a GFR less than 25?
0.6g/kg/day of protein
reduces generation of nitrogenous wastes
retards the progression of renal failure
What are the proteins requirements for pts on HD with malnutrition?
1.2-1.3 g/kg/day
What is the DOC for proteinuria? Why?
ACE or ARB
1) dec protein by 65%
2) dec glomerular capillary pressure
3) 40% reduction in progression to nephropathy
4) used in pts with or without HTN
5) No one agent superior over another
6) No target dose set-titrate to maximum tolerated dose
There is a 10% change of angioedema when giving ARBs so make sure to give in the presence of a HCP.
True
What do you monitor when giving ACE/ARBs for renal protection?
Monitor SCr, K, Bp
Discontinue if SCr is increased by 30%,
hyperkalemia, or dec Bp
how often do you titrate the dose in ACE/ARB pts for proteinuria?
q1-3 months
What are the brand and generic of ACEs and ARBs
Benazapril - Lotensin Captopril - Capoten Lisinopril - Zestril, Prinivil Ramipril - Altace Enalapril - Vasotec
Losartan - Cozaar
Olmesartan - Benicar
Telmisartan - Micardis
Valsartan - Diovan
non-dihydropyridine CCBs: do they help with proteinuria?
Yes, suppress glomerular hypertrophy and dec salt accumulation
Do Dihydropyridine CCBs help with proteinuria?
Norvasc (amlodipine) - NO EFFECT ON PROTEIN EXCRETION
What is the preprandial, postprandial and HB A1c goal for DM and CKD?
pre - 70-120
post- <7%
What is the BP goal for CKD and proteinuria?
<125/75
T or F: an inc in BP can lead to a Dec in GFR?
True
What is the LDL goal for CKD?
<100 mg/dL
DOC for hyperlipidemia in CKD?
HMG-CoA reductase inhibitors
Is smoking cessation and anemia tx good for CKD?
Yes
When you have CKD what happens to Na and fluid?
dec Na excretions and inc fluid retention
What is the tx for in fluid and dec Na excretion?
loop diuretics
Thiazides not effective when GFR <30
What are some Loop Diuretics and Thiazide Diuretics?
Furosemide
Torsemide
Bumetanide
Ethacrynic acid
HCTZ
Chlorothiazide
Chlorthalidone
Metolazone
How does CKD lead to hyperkalemia?
Dec nephron mass leads to dec tubular secretion of K
What happens when K gets above 5.5?
EKG changes might begin to occur
What is the definition of Anemia in reguards to Hbg level? What are some causes?
<11g/dL
Dec in EPO production
shorter lifespan of RBC
Iron deficiency
Blood loss
In a normal kidney, if Hb, Hct or O2 is decreased the kidney will produce more EPO to make up for the loss. What happens is CKD?
after a dec in nephron mass there is dec Hb, Hct, and O2 but no subsequent INC in EPO and thus this leads to anemia
What are some sxs of anemia?
Cold intolerance, SOB, decreased exercise capacity;
LV hypertrophy, EKG changes, CHF, impaired mental cognition, sexual dysfunction
What does MCV stand for?
mean Corpuscular volume, or Mean Cell Volume, its the average size of a RBC
What do Erythropoiesis-Stimulating Agents do?
They bind to the erythropoietin receptor to save RBC progenitor cells from death
What are the two ESA?
Epoetin alfa and Darbepoetin alfa
What is the brand name of Epoetin alfa and what is the route of administration? What is the Dose?
Epogen, Procrit
SQ, IV, intraperitoneal
SQ: 80-120 units/kg/week divided into 2-3 doses/week
IV: 120-180 units/kg/week divided into 2-3 doses/week
What is the brand name of Darbepoetin alfa and the route of administration? What is the Dose?
Aranesp
SQ, IV
0.45 mcg/kg/week
Dose adjustments of ESA should be based on ____ and you should monitor it q 1-2 weeks then 2-4 weeks when stable. The Increase should not be >___ every month
Hg
1-2 g/dL of Hg every month
What is a side effect ESA?
HTN and iron store depletion
What is a common cause of ESA resistance?
iron deficiency
Most pts will require ___ to replete iron stores
1g of elemental iron; smaller doses over several weeks, oral iron supplement not effective
What are the three IV iron options?
Iron Dextran
Ferric Gluconate
Iron Sucrose
Which iron store supplement IV requires the higher maintenance dose?
Ferric Gluconate (because its Ferric not Ferrous)
All IV iron preparations are equipotent, which one has the most side effects?
Iron Dextran
- anaphylatic reaction, arthralgias/mialgias
- give 25mg test dose over 30mg
- not used much
Other common SE IV iron:
- hypotension
- flushing
- nausea
- injection site reactions
Dec renal function dec ___ excretion and dec _____ production which causes the PTH to increase and cause secondary hyperparathyroidism
PO4, Calcitriol
What is the role of PTH?
stimulates osteoclasts to resorb bone, inc Ca levels, stimulates kidney to reabsorb Ca while inhibiting the reabsorption of PO4, it also activates Vit D;
Ultimatly PTH in Ca and dec Phos
The higher the PTH the _____ the ClCr.
lower
What is calcitriol? What does it do to PTH and PO4?
activated Vit D
decreases PTH
increases PO4
T or F: most pts with CKD have some form of bone remodeling.
True
What happens if CaxPO4 is >55?
crystal deposition in vascular and soft tissue
What are some sxs of hyperparathyoidism?
fatigue, MS and GI complaints, bone pain and fractures, findings of calcifications in vascular tissue
Tx for hyperparathyroidism.
Dietary restriction of Phosphorus to 800-1000mg/day
Dialysis
Parathroidectomy
Phosphate Binders (Ca Carb, Ca Acetate [PhosLo])
What is PhosLo?
Calcium acetate
a calcium-based phosphate binder that binds to PO4 in the GI and excretes it
What is better Ca Acetate or Ca carbonate?
Ca Acetate
What must you be cautious of when using Ca binders?
Pts with a Ca level at the upper end of normal due to potential inc in Ca to a CaxPO4 > 55
What are some side effects of Ca Carb and Acetate?
Constipation and Hypercalcemia
How long must you separate PhosLo from meals?
1 hr before and 3 hours after other meds
SHould you take Ca Acetate with food?
yes
How much elemental Ca is in Phos-Lo?
25%
What are the Aluminum-Based phosphate binders and what are they used for? What does it cause as a side effect?
Aluminum hydroxide, aluminum carbonate
Effectively lower PO4 levels
may cause aluminum toxicity and constipation
What is Sevelamer and what is it used for? When would you use it?
Renagel
PO4 binder in GI and excretes it in feces; not systemically absorbed
Does not contain Ca or Al
It costs alot but you would consider to use it if the CaxPO4 is >55
What is the dose of Sevelamer? What are some side effects of Sevelamer?
800mg TID with meals
N/D/constipation
What is Lanthanum? When should it be considered? Should it be swallowed whole?
Fosrenol
it binds to dietary PO4
Consider if Ca-PO4 >55
chew, do not swallow whole
What is the dose of Lanthanum?
750mg to 1.5g/day in divided doses with meals
What are some side effects of Lanthanum (Fosrenol)
abdominal p;ain, diarrhea, N/V
What does Vit D therapy do to PTH?
suppress PTH synthesis and reduce PTH concentration; consider when dec in PO4 dose not dec PTH
What could Vit D to do Ca and PO4 levels?
Increase them; pulse therapy may be preferred over daily therapy
Check Vit D levels if PTH is low. T or F
False
Initiate therapy of Vit D if level <30 ng/ml. T or F?
True
What is the most active form of Vit D and what is its MoA?
Calcitriol
upregulate vit D receptor in parathyroid gland to then dec PTH synthesis and secretion
Inc Ca and PO4 absorption in intestines
What are some Calcitriol agents?
Rocaltrol and Calcijex
What Ca product do you consider in pts with elevated Ca-PO4?
Paricalcitol because it has less mobilization of Ca from bone and dec absorption of Ca from the gut
After starting Vit D therapy, what labs should be monitored?
PTH, Ca and PO4
What happens if you oversuppress the PTH?
dec osteoblast, osteoclast activity
dec bone formation
low bone turnover
What is Cinacalcet’s Brand name and what is it used for?
Sensipar
It is a calcimimetic that attaches to Ca-R on parathyroid gland to tell the gland that there is enough circulating Ca and to stop production and secrection of PTH
What are the advatages of taking Cinacalcet?
initial dose of 30mg regardless of PTH level
can be used in pts irrespective of phosphate binder or Vit D analog use
Goal PTH <250 pg/mL
After starting Cinacalcet, what sould you monitor for and what P450 CYP enzyme is it a substrate for? What drugs do you have to watch out for inc levels of Cinacalcet?
watch for hypocalcemia
-if you develop hypocalcemia inc the cal containing binder dose and inc vit D analog dose
CYP2D6 –> Ketoconazole inc cinacalcet concentrations
What types of vitamins does HD remove?
water soluble (Vit C and Vit B (folic acid))
What vitamins to you want to supplement and what vitamins do you want to avoid in HD pts?
Vit B complex and Vit C
avoid A,E,K
What is RRT?
Dialysis or kidney transplantation
What are the indications of RRT? vowels
Acidosis Electrolyte abnormality Intoxication fluid Overload Uremia
What does HD do?
solute is moved across the dialyzer membrane from an area of higher concentartion to a lower concentration (dialysate) to remove small molecules like electrolytes; utrafiltration can remove water from bloodstream
convention can remove dissolved solutes
What are some complicatiosn of HD?
hypotension cramps N/V HA/chest pain/backpain infection/thrombosis
Is peritoneal Dialysis effective?
Less effective than HD
What is the tx for Peritonitis?
1st gen cephalosproins, Vanco for Gam +
3rd or 4th gen cephalosproins, aminoglycosides, FQ for gram -
What is Anuria, oliguria, non-oliguria?
anuria 400ml/day
Can you use the CCG equation when you are in acture renal failure?
No because SCr is not at steady state
There is ARF from Pre-renal, Intrinsic and Post-renal. What is an example of each?
Pre-renal: dec renal perfusion (dec blood flow to the kidney)
Intrinsic: glomerular, interstitial, tubular (ATN), bascular
Post-renal: obstruction of urine flow
Whcih ARF form has NO tissue damage?
Pre-renal ARF; rapidly reversible upon restoration of RBF(Renal blood flow) and GFP (glomerular filtration pressure)
What are some causes of Pre-renal ARF?
Low cardiac output Drug induced - NSAIDs - ACEIs - Cyclosporine and tacrolimus
How does ACEIs cause Pre-renal ARF?
They block the production of ATII which dec BP in the glomerulus and dec renal perfusion
What are some examples of intrarenal ARF?
Tulubar cell damage, etc
What is the Fractional Excretion of NA equation and what does it tell us?
(Urine Na x Serum Cr)x100 / (Serum Na x Urine Cr)
if 1% its Acute Tubular Necrosis (ATN)
What is the most common cause of ARF?
ATN
In ATN, tubules are damaged by _____ or _____ resulting in dequamation of tubular cells, intraluminal tubule obstruction, and back leakage of glomerular filtrate
ischemia (pre-renal)
toxins
Can Aminoglycosdies cause ATN?
Yes
How long after tx?
5-10 days of tx with aminoglycosides
What type of urine output is it?
non-oligouric
Will you see electrolyte abnormalities?
Mg, K, others
How do you tx and what is the recovery time?
supportive care, usually within 3 weeks it recovers
How long after a radiocontrast will you develop ARF? can it be prevented?
24-48 hours
Hydration pre and post tx
benefits of Na bicarbonate and N-acetylcysteine
What is Intersitial nephritis? What causes it?
inflammation localized to the renal interstitum and tubules
Drugs:
penicillins, diuretics, anticoagulatn,s NSAIDs
What is the onset and tx for AIN?
3-5 days for up to several wks
Tx by discontinuing med and possibly using PO steroids
Will maintining high volume expanision and high urine flow help dec ARF risk?
Yes
If you have volume depletion how do you tx it?
resuscitation fluid
if you phave pulmonary edema how do you tx it?
IV nitroglycer
IV lasix
BIPAP/Intubation prn
Dialysis
What is the most life threatening electrolyte in ARF?
hyperkalemia; not eliminated by kindey adequately
If the pt is above 5.5 and has EKG changes how do you tx them?
Insulin/Dextrose - stimulates Na/K/ATPase
Sodium Bicarbonate - stimualtes the Na/K/ATPase pump
Ca gluconate causes hyperpolarization and stabalizes the membrane potential to not depolarize and cause EKG changes
Sodium polystyrene sulfate (Kayexalate) - its a Na, K exchanger and excretes it in the feces
Can you give albuterol to lower K levels? How does it work?
Yes; causes intracellular shift of Na/K/ATPase
What form of potassium lowing drug works the fastest?
Ca gluconate
What one is the slowest?
HD or K exchange resin (Kayexalate)
Can ARF cause hypocalcemia?
Yes, tx if symptomatic w/ 10-20ml 10% Ca gluconate
If you have pre-renal AFR what are some things you can do to tx it?
tx underlying cause
inotropes to inc cardiac output to kidneys
stop NASIDs and ACE/ARBs
When do you use a crystalloid compared to a colloid?
Crystalloids: use in hypovolemia (shock, dehydration)
Colloids: use in hypovolemia due to hemorrhage
What predicts worse outcomes: oliguric ARF or non-oliguric ARF?
oliguric ARF (<400ml/day) common practice to attempt to increase urine flow
What are three drugs used to increase urine output?
Dopamine
Mannitol
Lasix
When do you use Lasix?
Only after intravascular vol deficits are corrected and they have maintined hydration; helps kidneys to start working again
How does a loop diuretic help the kidney
increases renal blood flow
How does mannitol help the kidney
reduces cell swelling
What is the main goal of these diuretics and mannitol?
to maintain U/O
What is the most commonly used Loop diuretic for fluid correction in ARF?
Furosemide
-initial dose of 40-80mg IV bolus
Is Bumetanide 40x more potent than fursoemide?
Yes
When should you use Ethacrynic acid as a diuretic?
When pt has sulfa allergy but it may be ototoxic
What are some side effects of Loop Diuretics?
ototoxicity, vertigo, cramping, rash, pruritis, electrolyte abnormalities
What do you monitor when on Loop Diuretics?
U/O, renal function, electrolytes, glucose
What drug is an osmotic diuretic?
Mannitol 20% solution give 12.5-25mg IV bolus over 3-5min may repeat in one hour if no response D/C if no response after second dose Max dose 50g/day
What are some side effects of Mannitol?
extracellular fluid expansion (CFH, pulm, edema, HTN)
HA, N/V/D, HTN, CFH
pulmonary edema
What do you monitor when on Mannitol?
U/O, renal function, chest X-ray
CV status
What does low dose dopamine do for renal blood vessels?
selectively dilates them and inc renal blood flow to potentially inc GRF and inc UOP
What are some side effects of Dopamine?
Vasoconstriction at high doses, tachycardia, angina
pulmonary edema?
What do you monitoar when on dopamine?
U/O, blood pressure, Cardiac output
What is Fenoldopam?
Dopamine agonist (D1)
What does it do for the kidneys
inc Renal Blood Flow (RBF) Na excretion Urine volume Dec systemic BP May or may not inc GFR
Most data shows that Fenoldopam is good a preventing what?
rediocontract dye induced nephropathy
What electrolytes do you want to restrict in ARF?
K and Na
Do pts in ARF need protein?
yes to maintain a + nitrogen balance but can worsen uremia
What is the most common reason for death in ARF?
Infection
Tx flow:
Determine if pre-renal, renal or post-renal failure then tx life-threatening complications the restore volume then give diuretics to restore UOP Dont forget to remove toxins
When decreases doses of drugs for renal failure you have to make sure not to dec doses of drugs that have a bigger benefit than risk, like:
antibiotics; tx infections aggressively
