Chronic Kidney Disease Flashcards
Why should we caution against using serum creatinine alone as a measure of kidney function?`
Serum creatinine amounts changes depending on the person’s muscle mass (more muscle –> more creatinine). So some people may have more or less than the “normal” range in the clinical setting.
How can we account for difference between people when measuring serum creatinine as a measure of GFR?
Put the serum creatinine into 1 of the 3 biometric equations
Cockroft Gault, MDRD, CKD-EPI
What is the official definition of Chronic Kidney Disease?
A structural or functional abnormalities for more than 3 months as manifested by either a decrease in GFR OR other kidney damage types
What is the GFR cutoff for diagnosing CKD?
GFR <60 ml/min/1.73m2
If you have a kidney transplant does that classify you as having CKD?
Yes, if you have a kidney transplant you are considered to have CKD.
Staging of CKD is based solely off of the…?
GFR
Describe the GFR at each stage of CKD:
Stages 1-5.
Stage 1: >90 Stage 2: 89-60 Stage 3a: 59-45 Stage 3b: 30-44 Stage 4: 15-29 Stage 5: <15
Explain why CKD stage 1 has a GFR that’s above 60.
Stage 1 CKD has a GFR >90 which is normal, but there can be a structural abnormality with the kidney that leads to this classification (ie. microalbuminuria)
How much of the medicare budget is spent on CKD?
20% despite CKD making up 1/10 of the medicare population.
It’s very expensive to care for CKD.
What is the most common cause of CKD? The second?
- Diabetes
2. Hypertension
What are major organ systems affected by CKD?
Cardiovascular - greatly affected Neurologic Hematologic Bone Mineral Metabolism Electrolytes and Volume Status
How does CKD affect renal sodium handling?
CKD decreases the kidney’s ability to secrete or resorb sodium.
Prone to developing hypovolemia and hypervolemia
In CKD we typically recommend patients decrease____ and ___ intake.
sodium and water
Potassium handling is primarily mediated by…?
Aldosterone
More aldosterone = Less K+
What do recommend to patients in regards to potassium when they have CKD?
Limit potassium intake
Avoid medications that cause hyperkalemia (bactrim)
What is the major type of metabolic acidosis in CKD patients? NAGMA or AGMA?
NAGMA - Decreased Ammonia production in the proximal tubule leads to increased H+ floating around in the blood because there isn’t enough ammonia to bind it.
In CKD patients with Metabolic Acidosis we recommend..
Sodium bicarbonate supplementation.
In addition to “GOLDMARK,” two other causes of AGMA are…?
Phosphate and Sulfate Retention
The Kidney uses alpha 1 hydroxylase to convert….?
25 hydroxy Vit D (inactive) –> 1, 25 hydroxy VitD (active calcitrol)
What are the 3 treatment options for Renal Osteodystrophy (Secondary hyperparathyroidism)?
Give Phosphate Binders - FIRST THING!
Give 1,25 Hydroxy Vit D (Calcitriol) – Brings up serum Ca2+
Use PTH inhibitor - save bones!
Describe the effect CKD has in the progression of anemia. (3)
- Inflammation –> Iron cannot be incorporated well into the RBC’s
- Decreased EPO –> Less RBC’s
- Decreased RBC life span
Describe the effect CKD has on platelets.
Platelet dysfunction
Poor platelet adhesion - predisposition to bleeding
Toxin Retention
How do you treat platelet dysfunction in the setting of CKD? (2)
DDVAP (Desmopressin)
Dialysis - if severe
How do you treat anemia in the setting of CKD? What is the goal?
Use EPO stimulating agents.
Goal Hgb is 10-12g/dL
If you go over 12 you can cause stroke or HTN.
What are major complications of CKD on the cardiovascular system?
HTN
Sudden Cardiac Death (SCD), Coronary Artery Disease (CAD) – Due to electrolyte imbalance
Uremic Pericarditis - Due to uremia
How do you treat cardiovascular system complications in the setting of CKD?
HTN - Diuretics, limit salts, ACE/ARBS, Vasodilators
Dialysis
What are two neurologic complications that can arise from CKD?
Uremic Encephalopathy - poor cognition and asterixis
Peripheral Neuropathy - peripheral motor and sensory issues (ie.restless leg syndrome)
What is asterixis? What treatment should you think of when it presents in the context of CKD?
Tremor where you can’t hold your hand out (“STOP”)
Treat with DIALYSIS!
How should you treat peripheral neuropathy?
Gabapentin
Dopamine Agonists
In CKD, describe what pruritis and calciphylaxis are and what could cause them?
Pruritis - itching due to hyperphosphatemia
Calciphylaxis - Calcium deposition in blood vessels that manifests on skin as ulcers
What is the goal blood pressure for patients with CKD? With CKD and proteinuria?
CKD - <140/90
CKD w/ proteinuria - <130/80
In patients with acidosis and CKD, we should treat with…?
Sodium Bicarbonate or Baking Soda.
Do statins slow the progression of CKD?
No, but they help the heart.
Why do we ask CKD patients to limit protein intake?
Protein can lead to an increase in GFR which isn’t good!
What are the indications for starting Dialysis in patients with CKD?
Acidosis- Unresponsive to bicarb therapy
Hyperkalemia - Unresponsive to medical therapy
Fluid overload - Unresponsive to diuretics
Symptomatic Uremia
What are the two ways in which proteins further the progression of CKD?
1) Bradykinin increase –> Increased RBF –> Glomerular damage and proteinuria
2) Increased sodium & amino acid resorption –> Macula Densa senses low Na+ –> afferent arteriole dilation –> Increased RBF –> Glomerular damage and proteinuria
Can ACE/ARBs cause hyperkalemia? How?
Yes, by blocking aldosterone
Can beta blockers cause hyperkalemia? How?
Yes, by increasing movement of K+ from the ICF compartment to the ECF compartment.
Does blood glucose affect the progression of CKD? How?
Yes, it increases proteinuria.
This is why it is critical to maintain good blood glucose control
What is the goal range of proteinuria that we want for patients with CKD?
0.5g protein/day
Should you do dialysis if a patient has acidosis? (Or any of the AIEOU symptoms?)
You should only dialyze if the patient has a problem UNRESPONSIVE to medical therapy.
In uremia you will automatically treat.
At which stage of kidney failure is renal replacement therapy primarily indicated? What is the GFR at this stage?
Stage 5 CKD - Kidney Failure, GFR < 15
Patient does not need dialysis if medications have not been fully utilized.
