Case 13 - AKI - Progress Test

Question 1

What are the categories of cause of AKI?

Answer 1

• Prerenal
• Intrinsic
• Postrenal

Question 2

What are examples of prerenal causes of AKI?

Answer 2

• things that cause decreased blood flow eg:

Hypovolaemia secondary to diarrhoea or vomiting

Renal artery stenosis

Question 3

What are examples of intrinsic causes of AKI?

Answer 3

• GN
• Acute tubular necrosis
• Acute interstitial nephritis
• Rhabdomyolysis
• Tumour lysis syndrome

Question 4

What are examples of post renal causes of AKI?

Answer 4

• Kidney stones
• BPH
• external compression of the ureter (eg. tumour)

Question 5

What are risk factors for AKI?

Answer 5

Chronic kidney disease 
Other organ failure / chronic disease 
History of AKI 
Nephrotoxic drugs (eg. NSAIDs, aminoglycosides, ACE-i, ARBs, diuretics) 
Contrast 
> 65 
Oliguria (Urine ouput < 0.5 ml/kg/hr) 
Neurological / cognitive disability

Question 6

What are signs of AKI?

Answer 6

Reduced urine output
Pulmonary / peripheral oedema
Arrythmia
Features of uraemia (pericarditis / encephalopathy)

Question 7

What is is the diagnosis criteria for AKI?

Answer 7

Rise in serum creatinine > 26 micromol/l within 48hrs

> 50% rise in serum creatinine within the past 7 days

Fall in urine output to < 0.5 ml/kg/hr for more than 6 hrs in adults

Question 8

What medications should be stopped in AKI?

Answer 8

NSAIDs (except aspirin at a cardiac dose eg. 75mg od)

Aminoglycosides

ACE-i

ARBs

Diuretics

Question 9

What drugs may have increased toxicity in AKI?

Answer 9

Metformin
Lithium
Digoxin

Question 10

What drug is used to stabilise the cardiac membrane in hyperkalaemia?

Answer 10

IV Calcium gluconate

Question 11

What drug is used to promote potassium movement from the extracellular to the intracellular space in hyperkalaemia?

Answer 11

IV insulin / dextrose

Neb. salbutamol

Question 12

What is used to remove calcium from the body in hyperkalaemia?

Answer 12

Oral / enema calcium resonium
Loop diuretics
Dialysis

Question 13

What are the complications of AKI?

Answer 13

Hyperkalaemia
Fluid overload, heart failure and pulmonary oedema
Metabolic acidosis
Uraemia - encephalopathy / pericarditis

Question 14

How do you calculate the anion gap?

Answer 14

(Na + K) - (Cl + HCO3)

Question 15

What are the normal ranges of anion gap?

Answer 15

8-14

Question 16

What causes a metabolic acidosis with a normal anion gap?

Answer 16

GI bicarbonate loss: diarrhoea, ureterosigmoidostomy, fistula, renal tubular acidosis, fistula
Drugs: eg. acetazolamide
Ammonium chloride injection
Addison’s disease

Question 17

What causes a metabolic acidosis with a raised anion gap?

Answer 17

Lactate: shock, hypoxia 
Ketones: DKA, alcohol 
Urate: renal failure 
Acid poisoning: salicylates, methanol 
5-oxoproline: chronic paracetamol use