• 
• 

Three Part Question

In [critically ill patients with acute renal failure] does [the use of loop diuretics] help maintain [renal function]?

Clinical Scenario

A 70-year-old male is admitted to the intensive care unit with a severe biliary sepsis. He is develops multi-organ failure, is placed on a ventilator and receives inotropic and vasopressor support. He becomes anuric over the next two days, despite adequate fluid resuscitation. He is commenced on renal replacement therapy when he develops fluid overload. You wonder if you could have preserved his renal function and reduced his chances of requiring renal replacement therapy by the use of a loop diuretic.

Search Strategy

OVID Medline 1966 to February Week 3 2005.
(exp Kidney Failure, Acute/ or acute renal failure.mp. or acute kidney failure.mp. or ARF.mp.) and (exp Diuretics/ or exp Diuretics, Sulfamyl/ or loop diuretic$.mp. or furosemide.mp. or frusemide.mp. or bumetanide.mp. or ethacrynic acid.mp.) limited to English, Humans, Adults, (Clinical Trial or Randomized Controlled Trial)

Search Outcome

46 papers were found of which 4 directly answered the three part question.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Sirivella 2000 USA	100 patients with acute renal failure after cardiac surgery.	Randomized controlled trial	Need for dialysis.	Loop diuretics decreased need for dialysis in combination with mannitol and dopamine, not alone.	No diuretic free control. Only cardiac surgery patients.
Shillida 1997 UK	92 patients with acute renal failure	Randomized controlled trial	Renal recovery, dialysis, death	Loop diuretics do not alter mortality, or the need for dialysis	All patients received dopamine and mannitol also. Not critically ill/ICU patients.
Hager 1996 Switzerland	121 ICU patients post-thoraco-abdominal surgery or vascular surgery	Randomized controlled trial	Effect of low-dose furosemide on renal function	Furosemide did not prevent deterioration in renal function.	No patients with severe renal failure enrolled. No patient exclusion criteria.
Lumlertgul, 1989 Thailand	23 patients with falciparum malaria with acute renal failure	Randomized controlled trial	Effect of frusemide and dopamine on renal function	Frusemide did not alter the clinical course of renal failure. Frusemide and dopamine combination preserved renal failure if creatinine < 400mumol/l.	Small study. Only patients with malaria. No diuretic-free control used.

Comment(s)

There is no evidence that loop diuretics used alone help maintain renal function in critically ill patients with acute renal failure. There is some evidence that loop diuretics in combination with dopamine (Lumlertgul 1989) or dopamine and mannitol (Sirivella 2000) may preserve renal function in certain patient sub-groups.

Clinical Bottom Line

No evidence to suggest that in critically ill patients with acute renal failure the use of loop diuretics help maintain renal function.

References

1. Sirivella S. Gielchinsky I. Parsonnet V. Mannitol, furosemide, and dopamine infusion in postoperative renal failure complicating cardiac surgery. Annals of Thoracic Surgery. 2000; 69(2):501-6.
2. Shilliday IR, Quinn KJ, Allison ME. Loop diuretics in the management of acute renal failure: A prospective, double-blind, placebo-controlled, randomized study. Nephrol Dial Transplant 1997;12:2592 -2596.
3. Hager B. Betschart M. Krapf R. Effect of postoperative intravenous loop diuretic on renal function after major surgery. Journal Suisse de Medecine 1996;126(16):666-73.
4. Lumlertgul, D. Keoplung, M. Sitprija, V. Moollaor, P. Suwangool, P. Furosemide and dopamine in malarial acute renal failure. Nephron 1989; 52(1):40-4.