Approach to Patients witch CKD Flashcards
Chronic kidney disease (CKD) is defined as
eGFR <60 mL/min or kidney damage that persists for at least 3 months
What is a significant limitation of urine dipstick?
Measures concentration only, and can give falsely negative results in dilute urine
Define GFR
Volume of serum cleared by the kidneys per unit of time
Creatinine is produced from … and excreted by …
Muscle & kidneys
Normal creatinine
Men - 0.6 - 1 mg/dl
Female - 0.8 - 1.3 mg/dl
Serum creatinine levels are influenced by
Muscle mass, recent dietary intake (cooked meat), concomitant drug therapy
The main risk factors for progression of renal disease include:
Smoking, high blood pressure, hyperglycemia in diabetic patients
How does smoking impact the progression of renal disease?
Accelerates the rate of progression
Why are ACE/ARBs recommended in CKD?
Whether or not hypertension is present they are utilized to slow the rate of kidney disease progression in patients with proteinuria
- works by decreasing pressure in the kidneys
What and when to monitor with ACE/ARBs?
Blood pressure, potassium, and creatinine with initiation and after each dose change.
Check labs in 2-4 weeks
What percent of creatinine increase is expected when initiating ACE/ARBs and when should you expect to see it?
An increase of ~30% is ok, you should see this in the first two weeks, and it should stabilize in 2 to 4 weeks.
- Discuss discontinuing medication with the attending if the creatinine is higher than 30%
If there is a significant rise in creatinine when initiating ACE/ARBs what should you assess for?
Renal artery stenosis via renal artery duplex
Utilizing an ESA with hemoglobin =>13 g/dl is associated with
No benefit
CVA
Increased risk of cardiovascular complications
Death
The cause of iron deficiency is multifactorial but include:
Reduced absorption of iron
Blood loss from frequent blood draws or GI loss
Reduced nutritional intake
Ferritin’s serum levels reflect
Iron storage
What is the TSAT?
Total iron binding compacity
What is the TSAT goal?
=> 30%
How should ferritin be interpreted when assessing for iron deficiency anemia and why?
Cautiously
Ferritin increases with inflammation and CKD patients often exhibit chronic inflammation
TSAT of <20% is indicative of
Low iron availability
Describe the relationship between ESA and iron deficiency?
Iron deficiency can lead to decreased effectiveness of ESA therapy
How often should iron therapy be monitored?
Every three months
What labs should you order when monitoring iron therapy?
TSAT and ferritin
Hyperphosphatemia is associated with
Increased risk of vascular calcification and left ventricular hypertrophy in ESKD
Hyperparathyroidism is associated with
Bone disease
Why does the PTH range increase with CKD?
As CKD progresses, the bone becomes resistant to the actions of PTH and so the target PTH range increases
In non-dialysis CKD patients what is the recommended first-line treatment for elevated PTH?
Vitamin D
How does CKD progression affect 25-D /1,25D and PTH?
Serum levels of 1,25D may be reduced and PTH suppression may be inadequate
What drug class is cinacalcet?
Calcimimetic
What does cinacalcet do?
Increases the sensitivity of calcium receptors on the parathyroid gland to calcium, resulting in decrease PTH secretion
How does chronic metabolic acidosis affect bone health and CKD?
Results in increased resorption of bone, an increased rate of progression of CKD
What is the effect of dialyzer blood flow rate on clearance?
The volume of blood cleared of urea increases as blood flow rate increases
What is the effect of dialysis solution flow rate on clearance?
Faster dialysis solution flow rate increases the efficiency of diffusion of urea however it is usually modest.
What is the optimum dialysis solution flow rate?
1.5-2 times the blood flow rate
Kt/V urea goal
> 1.2 or 1.2-1.4 depending on the attending
