AKI

Question 1

Describe Acute kidney injuries (AKI)?

Answer 1

• Syndrome of acute decreased renal function
• Measured by serum creatinine or urine output

Question 2

Kidney Diseases: Improving Global Outcomes (KDIGO) guidelines for defining AKI?

Answer 2

• Urine output <0.5ml/kg/h for 6 hours
• Rise in creatinine x1.5 baseline within 7 days

Question 3

Describe how AKIs can be staged?

Answer 3

• According to:
  
  • Creatinine rise
  • Period of oligouria

Question 4

Name some risk factors for AKIs?

Answer 4

• Pre-existing CKD
• Age
• Male sex
• Comorbidities:
  
  • DM, CVD, malignancy

Question 5

Describe the categories of aetiology of AKIs?

Answer 5

• Pre-renal
  
  • Reduced perfusion of the kidney
• Renal
  
  • Intrinsic renal disease
• Post-renal
  
  • Obstruction to the urinary tract

Question 6

Aetiology of AKIs

Answer 6

Question 7

What should be monitored in someone suspected of an AKI?

Answer 7

• Fluid balance
  
  • Catheter, hourly urine output
• K+
• Lactate (if signs of sepsis)
• Daily creatinine until it falls

Question 8

Investigations into an AKI?

Answer 8

• Urine dipstick (pre-catheter)
  
  • Quantify proteinuria, haematuria
• USS kidneys
  
  • Small kidneys suggests CKD
• Check liver function
  
  • Hepatorenal disease
• Assess platelets: if low => blood film to assess for haemolysis
• Investigate for intrinsice renal disease
  
  • ANA, ANCA, anti-GBM

Question 9

Name some nephrotoxic medications which should be stopped if signs of an AKI?

Answer 9

• NSAIDs
• ACE-i/ARB
• Aminoglycosides
  
  • eg Gentamicin

Question 10

Describe the management of a pre-renal AKI?

Answer 10

• Correct volume depletion
  
  • Once corrected, fluid intake should match urine output + 500mL
  • To cover insensible fluid losses
• If hyperkalaemia:
  
  • Calcium resonium for myocardium stabilisation
  • Glucose and insulin
• If acidotic:
  
  • Sodium bicarbonate
• Treat any underlying infections

Question 11

Describe the management of a renal AKI?

Answer 11

• Refer for biopsy
• Specialist treatment of intrinsic renal disease

Question 12

Describe the management of a post-renal AKI?

Answer 12

• Catheter
• Nephrostomy
  
  • artificial opening created between the kidney and the skin which allows for the urinary diversion directly from the renal pelvis
• Urological intervention

Question 13

Complications of an AKI?

Answer 13

• Fluid depletion
• Acidosis
• Hyperkalaemia

Question 14

Signs of hypovolaemia?

Answer 14

• Low BP, fast pulse
• Reduced urine output
• Non-visible JVP
• Poor tissue turgor

Question 15

Signs of fluid overload?

Answer 15

• Raised BP, JVP
• Lung crepitations
• Peripheral oedema

Question 16

Describe the fluid resuscitation of hypovolaemia?

Answer 16

1. 500ml crystalloid over 15 minutes
   
   • Hartmann’s, ringers lactate, plasmalyte
2. Reassess fluid state
3. Further 250ml boluses can be give after review
4. Stop when euvolaemic

Question 17

Describe the management of fluid overload?

Answer 17

• Oxygen if required
• Fluid restriction
• Diuretics (only symptomatic overload)
• Renal replacement therapy

Question 18

Describe the management of hyperkalaemia as a consequence of AKI?

Answer 18

• Treat K+ >6.5 or with ECG changes
  
  • 10ml 10% calcium chloride IV via big vein
    
    • or 30ml 10% calcium gluconate
  • IV insulin in 25g glucose
    
    • stimulates intracellular uptake of potassium
  • Salbutamol
    
    • intracellular potassium shift in high doses
  • Renal replacement may be required for definitive removal of K+

Question 19

What additional mediation can be given to patients with AKI?

Answer 19

• PPI
  
  • Reduce the risk of them developing an upper GI bleed

Question 20

Complications form treating AKIs?

Answer 20

• Pulmonary oedema
  
  • Excess IV fluid input
  • If pulmonary oedema occurs and urine output cannot be restored
    
    • => Dialysis
• Dilutional hyponatraemia
  
  • Excess oral fluid intake