Acute renal failure and the critically ill surgical patient.

Acute renal failure can occur following major surgery. Predisposing factors include massive haemorrhage, sepsis, diabetes, hypertension, cardiac disease, peripheral vascular disease, chronic renal impairment and age. Understanding epidemiology, aetiology and pathophysiology can aid effective diagnosis and management. A consensus definition for acute renal failure has recently been developed. It relates to deteriorating urine output, serum creatinine and glomerular filtration rate. In the surgical patient, precipitants are often pre-renal, although intrinsic damage and obstructed urine flow can occur. Worsening renal function results in distal organ damage. Acute renal failure is a marker of disease severity, carrying a poor prognosis if associated with deteriorating respiratory and cardiovascular function. Acute renal failure in the critically ill surgical patient exerts a massive impact on the evolution of complications and prognosis. Management relates to treating life-threatening problems, maintaining effective ventilation and circulation, removal (or reduction) of nephrotoxins and, where appropriate, establishing either renal replacement therapy or palliative care.