Acute renal failure
Definition: Significant decline in renal
function over hours or days.
Diagnosis
↑urea ↑creatinine.
No specific signs or symptoms.
Treatment
Complications
- Hyperkalaemia (ECG monitoring, do NOT rely on lab tests!)
- Pulmonary oedema←salt & water overload. Emergency haemodialysis
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.
Contraindications
- Aminoglycosides
- Tetracyclines (except Doxycycline)
- Amphotericin B
- NSAIDs
- ACEI/ARB
Indications for renal replacement therapy
- Hyperkalaemia
- Fluid overload→pulmonary oedema
- Acidosis→circulatory compromise
- 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.
Prognosis
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.