Pre-re(n)ading Flashcards
(31 cards)
What are the functions of the kidney?
Electrolyte homeostasis
Waste product excretion
Hormone - EPO, vitamin D,
Acid base balance
Water and salt production
Drug clearance
ewew
Which cells of the kidney deal with electrolytes?
Tubular cells - in proximal and distal tubular cells
Which electrolyte is most deranged in CKD?
Potassium
What ECG changes do you get with hyperkalemia
Tented T waves
Broadened QRS (more than 3 squares)
Hyperkalemia management (rapid fire)
Calcium gluconate
Dextrose
Insulin
How would you manage patient with hyperkalemia (fully)
This is a medical emergency, ask for senior help
A to E - assess for cardiac changes/compromise
Do a 12 lead ECG - repeat to ensure it’s not spurious
Repeat Us and Es and request CK if rhabdomyolysis
Review/stop any drugs contributing
Call for senior help
10 ml 10 % calcium gluconate
10 percent 100ml dextrose
10U rapid insulin (you only give a tiny amount of insulin)
(check these values)
(note this runs for 3 hours)
Keep taking bloods every 30-40mins / VBGs to check
Causes of hyperkalemia
Kidneys not filtering out potassium (due to drugs or kidney injury).
- ACE inhibitors
- Spironolactone
- Potassium sparing diuretics
Too much being taken in (
- chocolate
- tomatoes
- bananas
Too much being released from the cells
- tumour lysis syndrome
-rhabdomylosis
What else can be done to lower the potassium?
- Salbutamol - beta adrenergic receptor
- If the pt has renal failure or acidosis:
Give bicarbonate as this neutralised - Calcium resonium (potassium exchange) - in anuric hyperkalemia
- Zerconium - blocks potassium ion exchange in large bowel and prevents potassium reabsorption
How would you assess waste product
Urea and creatinine
Uremia - a condition where there is a problem with waste
What is urea? How is it made? When can you not rely on urea to interpret kidney function? What happens in dehydration
Urea - break down of proteins and break down of nitrogenous waste in liver
No liver - therefore no urea production - therefore you can’t use urea to interpret
dehydration = urea goes up more than creatinine
What is creatinine
Something made at a steady state by the muscles
Anything influences muscle bulk will influence creatinine
How do we calculate eGFR?
Creatinine can be used to create eGFR.
MDR equation for eGFR
Cockroft-Gault equation - also takes weight into
Why do we measure creatinine for eGFR?
It’s cheapest to measure
What can we used to measure eGFR more accurately?
Nuclear labelled EDTA
Previously it used to be inulin clearance
What is a newer way of interpreting kidney function?
Cystatin C
When can you start dialysis?
It always depends on
Someone with a generally lower creatinine would present with symptoms of uremia much earlier than someone with a large muscle bulk.
For example someone with a smaller muscle bulk
Urea of 20
Creatinine of 300
Note -
What drives EPO production?
Hypoxia inducing factor induces erythropoetin production gene
What can we give to E
What’s the enzyme that creates vit D
1 alpha hydroxylase
Calcium reabsorption
Problems of low calcium
Muscle contractility issues - esp in heart
Spasms, muscle cramps, seizures, parasthesias, seizures
What happens in kidney failure when vit D can’t get hydroxylated?
Low calcium, high PTH, resorb
