Sun31October0735PM 19

A 72-year-old old woman with a history of hypertension, chronic kidney disease and ischaemic heart disease presents via the Emergency department three days after coronary angiography for peripheral oedema and reduced urine output.

On examination BP is 170/80 mmHg. She has a raised JVP and pitting oedema to both legs. Serum creatinine is 500 µmol/L (baseline 150 µmol/L). Urinalysis is negative.

Which of the following is true?

(Please select 1 option)

Loop diuretics are contraindicated in this patient with AKI

Loop diuretics can be considered to treat fluid overload in this patient Correct

A creatinine of 500 µmol/L is an indication for starting renal replacement therapy (RRT)

Dopamine increases renal blood flow and improves outcomes in AKI

Loop diuretics should be used to maintain urine output in AKI

Explanation

Radio-contrast is directly nephrotoxic causing an oxidant injury to proximal tubular cells leading to acute tubular necrosis (ATN). Renal impairment usually recovers within one week although patients with pre-existing renal disease are liable to greater or permanent renal injury. ATN and acute kidney injury (AKI) significantly increase in-hospital mortality.

Prevention is key with adequate IV hydration, cessation of nephrotoxic drugs and consideration of N-acetlycysteine (evidence not robust for the latter).

Indications for RRT include:

refractory hyperkalaemia

refractory fluid overload/pulmonary oedema

metabolic acidosis

symptoms/complications of uraemia (for example, pericarditis, encephalopathy), and

exposure to certain toxins (for example, salicylate, lithium).

A creatinine value in isolation does not mandate haemodialysis and should be taken in context of the above factors.

Diuretics should not be routinely used in AKI and should never be given until hypovolaemia is corrected. However, loop diuretics can be considered in AKI to treat pulmonary oedema and fluid overload (high doses may be required and this should be discussed with a nephrologist).

There is no robust evidence that dopamine benefits outcomes in AKI and it may be harmful.

Reference:

NICE. Acute kidney injury (CG169).

The Renal Association. Acute Kidney Injury.

Answer Statistics

1

5%

2

85%

3

9%

4

3%

5

1%

Times answered: 271