Preventing Acute Renal Failure

Preventing Acute Renal Failure

Previously healthy patients most at risk of developing acute renal tubular necrosis are those with massive hemorrhage, multiple trauma, sepsis, extensive burns and crush injuries, especially if they already have some degree of renal impairment. Renal failure is diagnosed when urine output is persistently <0.5ml/kg/hour or the serum creatinine rises.

The maintenance of normovolemia and an adequate renal perfusion pressure are the two most important factors in avoiding acute renal failure. The urine output should be measured hourly and should be maintained above 1 ml/kg/hr.

Only after the patient is well resuscitated with fluid should vasoactive drugs be used to maintain an adequate mean arterial blood pressure for the patient (this will depend on the patient's preoperative blood pressure). If the patient becomes oliguric (urine output < 0.5 ml/kg/hr) despite adequate hydration and blood pressure administration of furosemide can be considered, up to 240 mg intravenously over 1 hour. If no diuresis develops further administration of furosemide is useless. All nephrotoxic drugs should be avoided if possible. These include NSAIDS and ACE inhibitors.

Electrolytes including potassium, sodium and bicarbonate must be measured at least daily during the perioperative period. Adequate calorie intake is essential and must be established as soon as possible postoperatively