Chronic kidney disease and renal failure Flashcards
How does kidney failure affect salt and water balance
Kidney failure tends to reduce secretion of salt and water leading to:
- Hypertension
- Oedema
- Pulmonary oedema
In what kind of circumstances can salt and water loss be seen though? (3)
- In tubulointerstitial disorders- damage to concentrating mechanism of urine
- Seen right after kidney transplant- there’s a bit of damage to tubules and they pee out a lot of water
- Seen also after kidney obstruction is relieved, kidney can’t concentrate urine and you get kidney failure
What may be a cause of AKI?
Hypovolemia
What does hyponatremia mean and what does it not mean?
What has this got to do with treatment of hyponatremia
- It does not mean reduced total body sodium
- It’s to do with how much free water you have- you’ll have more in hyponatremia.
You may not want to give them salt but instead remove the excess free water
1)What does hyponatremia mean and what does it not mean?
2)What has this got to do with treatment of hyponatremia
1)- It does not mean reduced total body sodium
- It’s to do with how much free water you have- you’ll have more in hyponatremia.
2)You may not want to give them salt but instead remove the excess free water.
Describe how acidosis happens in renal failure
- Reduced secretion of H+ ions which means you become acidotic
- Cells take up this H+
What does acidosis do to K+
The uptake of H+ ions by cells forces out K+ leading to hyperkalemia
-What are the 2 causes, then, of hyperkalemia?
-Acidosis
-Reduced distal tubule potassium secretion
What are the symptoms of hyperkalaemia? (3)
- Cardiac arrhythmias
- Neural and muscular activity
- Vomiting
What does symptom presentation of hyperkalemia depend on?
Chronicity of the disease- if it’s acute hyperkalemia then these symptoms show but if its chronic then body adapts and they don’t show
What ECG changes come up in hyperkalaemia? (6)
- Peaked T waves
- P waves broaden, have reduced amplitude and disappear
- QRS widening
- Heart block
- Asystole
- VT/VF (ventricular tachycardia/ventricular fibrillation)
What health consequences does this have? (Acidosis)(2)
- Anorexia
- Muscle catabolism
What effects does reduced EPO and reduced 1-25 Vit D levels have?
Reduced EPO → anaemia
Reduced 1-25 Vit D levels:
- Reduced intestinal
calcium absorption
- Hypocalcaemia
- Hyperparathyroidism
How does chronic renal failure 1-25 Vit D levels?
- There’s also phosphate retention in chronic renal failure (phosphate usually excreted by kidneys)
- This contributes to low levels of 1-25 vit D and hypocalcaemia and therefore hyperparathyroidism
What is the major outcome for a patient with CKD?
Cardiovascular disease
What standard cardiovascular risk is there for kidney failure patients? (3)
- Hypertension
- Diabetes
- Lipid abnormalities
What additional risks are there? (3) (in kidney failure)
-Oxidative stress
-Inflammation
-Bone/ metabolic disorders
What are the 2 main things we want to treat in initial management?
-Fluid balance
-Hyperkalemia
What are the three ways of managing hyperkalemia?
-Drive it into cells
-Drive it out of the body
-Reduce gut absorption
What are the two ways of driving potassium into cells?
-Insulin dextrose
-sodium bicarbonate
Why do we need to be careful with insulin dextrose?
- There are fatalities associated with it due to hypoglycaemia
- We only use it when potassium >6.5 or there are ECG changes
How do we drive K+ out of the body?
Diuretics/Dialysis
What do we use to classify CKD?
- Proteinuria
- ACR (albumin:creatinine ratio)
- GFR
What is the main method we use to assess kidney function?
Estimated GFR, the main factor in this is serum creatinine.
What is assosciated with more rosk of end stage renal failure?
More protein in the urine.
