AKI Flashcards
What is AKI?
A ‘syndrome’ arising from a rapidly falling eGFR
What is eGFR?
Estimated glomerular filtration rate
How is eGFR measured?
It is estimated using serum creatinine, alongside the patients age/sex/race
What are normal eGFR values?
Normal eGFR >90ml/min
What measurements and values constitute an AKI?
Serum creatinine >26.5 micromoles/L in <48hrs
OR
…a rise >1.5-fold from baseline in the preceding (before) 7 days
What are normal serum creatinine levels?
70-110 micromol/L
What nitrogenous things are retained in AKI?
Urea
Creatinine
What is a stage 1 AKI?
Serum creatinine rise >26.5 micromol/L in <48hrs
OR
…a rise in serum creatinine 1.5-1.9 fold from baseline
What is a stage 2 AKI?
A serum creatinine rise of 2.0-2.9 fold from the baseline
What is a stage 3 AKI?
Serum creatinine rise >3.0 fold from baseline
OR
…serum creatinine rises to >353.6 micromol/L
What are the 3 classifications of AKI?
Roughly what does each mean?
1) Pre-renal (volume depletion)
2) Intrinsic renal (kidney problem)
3) Post-renal (drainage issues)
What is cast nephropathy?
What type of AKI does this cause?
What other signs do myeloma sufferers have?
Myeloma cast nephropathy is when free Ig light chains (as the Ig’s do not form properly) form plugs in the renal tubules
It causes a intrinsic renal AKI
They also have hypercalcaemia (and bone pain) due to bone breakdown
Name some drugs which cause acute tubular necrosis and therefore intrinsic renal AKI’s.
(remember AAARI)
- amphotericin (anti-fungal)
- antibiotics (aminoglycosides) such as gent/streptomycin
- anti-retrovirals
- acetaminophen (paracetamol)
- radiocontrast
- IV Ig
Name 4 hormones or groups of hormones the kidneys synthesise.
- Erythropoeitin
- Renin
- Vit D
- Prostaglandins
Name 4 receptors found in the kidneys.
- ANP = vasodilates afferent areteriole, increasing GFR and sodium and water excretion
- ADH (vasopressin) = water reabsorption
- PTH = upregulates Vit D synthesis
- Aldosterone = sodium and water reabsorption and potassium excretion
What is a normal potassium level?
3.5 - 5.0mmol/L
What ECG response is seen in potassium levels 5.5-6.5mmol/L?
Tall tented ‘T’ waves
Prolonged PR segment
What ECG response is seen in potassium levels 6.5-8.0mmol/L?
Loss of P waves
Prolonged QRS complex
ST elevation
Ectopic beats
What ECG response is seen in potassium levels >8.0mmol/L?
Even wider QRS complexes
Sine wave ‘esque’ shape
Sever arrhythmias!!