CKD and Renal Failure Flashcards
What are the 4 main functions of the kidney?
Homeostasis
Endocrine
Excretory
Glucose metabolism
What are the endocrine functions of the kidney?
Erythropoietin synthesis
Have 1 alpha hydroxylase for the synthesis of vitamin D
What are the homeostatic functions of the kidney?
Electrolyte balance
Acid-base balance
Volume homeostasis
What are the excretory functions of the kidney?
Nitrogenous waste Hormones Peptides Middle sized molecules Salt Water
What are the functions of the kidney in relation to glucose metabolism?
Carry out some gluconeogenesis
Insulin clearance
What does loss of kidney homeostatic function lead to in terms of potassium, bicarbonate, pH, phosphate, salt and water?
High potassium Low bicarbonate Low pH (patients become acidotic when H+ cannot be removed) High phosphate Salt and water imbalance
What does loss of kidney endocrine function lead to?
Low calcium
Anaemia
High PTH
What does loss of kidney excretory function lead to?
High urea
High creatinine
Low insulin requirement
Why is insulin requirement low in those with kidney failure?
Kidneys get rid of insulin
What is the main systemic risk that increases in kidney failure?
Cardiovascular risk
When assessing a patient with kidney failure what question is it really important to adress?
What their fluid status is- are they hypovolemic, hypervolemic or euvolemic?
In hypovolemic kidney failure what will happen to levels of urea, creatinine, potassium, sodium, haemoglobin?
High urea High creatinine High potassium Sodium levels vary Low haemoglobin
What is important to remember in hyponatremia?
Hyponatraemia does not mean there is low total sodium in the body, it may just mean there is extra fluid, this is why assessing volume status is so important
Why might kidney failure patients not have anemia?
If they present early on eg due to toxin from food causing kidney failure then there may not be effects in the bone marrow
Why might patients with kidney failure not have high potassium levels?
If they have diarrhoea or are vomiting they may be getting rid of the excess potassium
In kidney failure what happens to secretion of salt and water? What are the effects of this?
It falls, tis causes hypertension, oedema, pulmonary oedema
What imbalance does acidosis contribute to?
Hyperkalaemia
Why is bicarbonate given to patients with kidney failure?
Mainly to treat hyperkalemia, but also to resolve the acidosis
What is the main issue with having a hyperkalemia?
It leads to cardiac arrhythmia which can eventually be deadly
What is seen on the ECG of someone with chronic kidney disease when they have arrhythmia?
First sign is peaking of T waves
P waves then disappear
QRS complex widens
Heart block, asystole, VT/VF may occur
Aside from arrhythmia what effects does hyperkalemia have?
Neural and muscular activity is disrupted
Vomiting
Why does anaemia arise in kidney failure?
Reduced erythropoietin
What are CKD patients most likely to die of?
Cardiovascular disease, not end stage renal failure
What does reduced vitamin D cause in patients with kidney disease?
Reduced calcium absorption
Hypocalcaemia
Hyperparathyroidism
How is fluid balance treated in kidney failure?
Hypovolemic give fluids
Hypervolemic- trail of diuretics/dialysis (dialysis if they aren’t peeing)
When deciding how to treat fluid balance in kidney failure what 2 questions do we need to address?
What is their volume status
Are they peeing?
What are the 3 ways to treat hyperkalemia?
Drive into cells via sodium bicarbonate or insulin dextrose (with caution due to risk of hypoglycaemia!!)
Drive out of body via diuretics and dialysis
Gut absorption via potassium binders
What is the main method of long term management of CKD?
Transplant if the patient is healthy
What does conservative management for CKD involve?
Erythropoietin injections to correct anemia Diuretics to correct salt water overload Phosphate binders (to prevent itching) 1.25 vit d supplements Symptom management eg anti-nausea
When is conservative management used in CKD?
In old patients, dialysis is an unpleasant process and often conservative treatment will help their symptoms in a much easier way
What are the 2 ways dialysis can be offered?
Home therapy or centre therapy
Why is it important to save veins of CKD patients and how do doctors do this?
They need their veins for dialysis, to help don’t take blood from their cubital fossa take it from the back of their hand and dont insert IV there
Why should you avoid transfusion in CKD patients?
If they are transplantable transfusion can sensitise them and reduce success of future transplant
How is anaemia ideally treated in CKD patients?
IV iron or erythropoietin
What are some methods of assessing GFR?
Urea Creatinine Radionuclide studies Creatinine clearance Inulin clearance
What method is commonly used to asses GFR? Why is ti good
eGFR (estimate of GFR)
Good as it takes into account age and sex but you have to account for ethnicity afterwards
On what basis are CKD patients classified?
GFR
Albumin: creatinine
