Acute renal failure is a medical emergency characterized by a rapid deterioration of renal function over hours to days that is often reversible. It accounts for 1% of hospital admissions and complicates around 7% of inpatient episodes, with mortality rates of 5-10% in uncomplicated cases and 50-70% in severe cases involving sepsis or the need for dialysis. Acute renal failure is commonly caused by pre-renal factors that decrease renal perfusion such as hypovolemia, post-renal obstruction of urinary outflow, or intrinsic renal disease including acute tubular necrosis, interstitial nephritis, or glomerular disease. Management involves treating the underlying cause, monitoring fluid balance, and considering

1. Acute Renal Failure Presented by: Dave Jay S. Manriquez RN.

2. Renal Failure Acute Chronic “ Acute renal failure is a medical emergency characterised by a rapid deterioration in renal function (GFR) over a period of hours-days. It is often reversible”

3. Epidemiology ARF accounts for 1% hospital admissions ARF complicates ~7% inpatient episodes Mortality from ARF 5-10% in uncomplicated cases 50-70% in severe cases (sepsis or need for dialysis)

4. Presentations Often no signs or symptoms Oliguria “ At risk” groups Elderly Hospital patients Severely ill Patients with chronic renal disease, diabetes or hypertension ↑ serum creatinine and urea

5. Assessment History & Examination, lab results, imaging ARF v. CRF CRF more likely if °acute illness, long duration of symptoms, previously ↑creatinine, anaemia. Obstruction? Previous hx of calculi, prostate symptoms, intra-abdominal mass, palpable bladder

6. Assessment II Is patient euvolaemic? Renal parenchymal disease? Urine dipstick & microscopy NSAIDs or Abx Major vessel occlusion?

7. Causes Pre-renal 40-70% Renal 10-50% Post-renal (obstruction) 10%

8. Causes – pre-renal Due to ↓ renal perfusion Hypovolaemia Blood loss: haemorrhage Fluid loss: D&V, burns Hypoperfusion Drugs: NSAIDs or ACEi Vascular: AAA or renal artery stenosis Hypotension (shock, sepsis) Cardiac failure

9. Causes - renal **Acute Tubular Necrosis** Ischaemia,, nephrotoxic drugs, radio-contrast media Interstitial nephritis Drugs: NSAIDs, contrast media Infection, granuloma, infiltration Glomerular disease Inflammatory Thrombotic Vascular Vasculitis, PAN…

10. Causes - renal

11. Causes – post-renal Urinary outflow obstruction Prostatic symptoms Intra-abdominal malignancy Renal calculi (intra-luminal) Strictures and tumours (intramural)

12. Management Speak to nephrologist No specific treatment of ARF (mainly supportive) Dopamine Insulin-like growth factor Natriuretic peptides Treat shock (but don’t fluid overload) Treat sepsis Exclude obstruction – catheter, USS Stop nephrotoxic drugs, NSAIDs, aminoglycosides, ACEi… Regular monitoring of fluid balance/weight Consider dialysis for uraemic patients

13. Complications Hyperkalaemia IV insulin and glucose IV calcium Metabolic acidosis Pulmonary oedema Oxygen Furosemide

14. Questions? References: OHCM “ Acute renal failure” Rachel Hilton BMJ 2006;333;786-790