Acute renal failure

Definition: Significant decline in renal function over hours or days.


↑urea ↑creatinine. No specific signs or symptoms.



Intravascular volume depletion

↓JVP, or postural hypotension.
Replace via peripheral line, resuscitate, then insert CVP monitor.

Determine & treat cause

Dipstix urine: blood &/or protein→urine microscopy, consider renal biopsy.
US—exclude obstruction, chronic renal failure.
Obstruction: urinary catheter, suprapubic catheter, antegrade nephrostomy.


Indications for renal replacement therapy

  1. Hyperkalaemia
  2. Fluid overload→pulmonary oedema
  3. Acidosis→circulatory compromise
  4. Uraemia→encephalopathy, pericarditis, bleeding
Consider when urea 40–50 mmol/l.

Intermittent haemodialysis by central venous catheter if# haemodynamically stable.
Continuous haemofiltration on ITU if unstable/multiorgan failure.


Of those requiring dialysis, 40% mortality.
Depends on whether the kidneys are the only organs to have failed: 5–10% if renal failure only. 50–60% if ventilation also required. Most common cause of death is sepsis.
Prognosis for recovery of renal function depends on cause.