Do diuretics exacerbate Acute Kidney Injury (AKI)?

From the Guidelines

Diuretics should not be used to treat acute kidney injury (AKI) except in cases of volume overload, as they may worsen the condition and increase mortality. The use of diuretics in AKI is a complex issue, and their potential benefits and risks must be carefully weighed 1. Loop diuretics, such as furosemide, have been shown to have no preventive effect on AKI and may even lead to increased mortality 1. However, in cases where volume overload complicates AKI, diuretics may improve outcomes 1.

Some key points to consider when using diuretics in AKI include:

• The medullary region of the kidney is metabolically active and relatively hypoxic, making it susceptible to further injury from diuretics 1
• Randomized control trials and meta-analyses have demonstrated that furosemide does not prevent AKI and may lead to increased mortality 1
• In cases of volume overload, diuretics may actually improve outcomes, as evidenced by the Fluid and Catheter Treatment Trial 1
• The potential benefits of diuretics in AKI are outweighed by the risks of precipitating volume depletion, hypotension, and further renal hypoperfusion, especially in hemodynamically unstable patients 1

In clinical practice, diuretics should be used with caution in patients with AKI, and their use should be guided by careful assessment of volume status and close monitoring of kidney function, electrolytes, and overall clinical condition 1. The general principle remains that diuretics should be used with extreme caution in the setting of AKI, and only in specific situations where the potential benefits outweigh the risks.

From the FDA Drug Label

In patients at high risk for radiocontrast nephropathy, furosemide can lead to a higher incidence of deterioration in renal function after receiving radiocontrast compared to high-risk patients who received only intravenous hydration prior to receiving radiocontrast. Reversible elevations of BUN may occur and are associated with dehydration, which should be avoided, particularly in patients with renal insufficiency

Diuretics and Acute Kidney Injury:

• The use of diuretics like furosemide may worsen acute kidney injury, particularly in patients with pre-existing renal insufficiency or those at high risk for radiocontrast nephropathy.
• Dehydration, which can be caused by excessive diuresis, should be avoided as it may lead to reversible elevations of BUN and potentially worsen renal function 2.
• It is essential to monitor patients closely and adjust the dosage of furosemide or other diuretics as needed to minimize the risk of worsening acute kidney injury 2.

From the Research

Diuretics and Acute Kidney Injury

• The use of diuretics in acute kidney injury (AKI) is a common practice, but its effectiveness is still debated 3, 4.
• Studies have shown that diuretics, such as furosemide, may help decrease symptoms of pulmonary edema secondary to volume overload, but they do not reduce mortality, the need for dialysis, or improve renal recovery 3, 5.
• The severity of AKI can affect the diuretic response to furosemide, and a good urinary response may be considered a proxy for residual renal function 6, 5.
• Continuous infusion of furosemide may be superior to bolus dosing in achieving a diuretic response, especially in septic shock patients on continuous venovenous hemodiafiltration (CVVHDF) 6.
• However, the current evidence does not suggest that furosemide can reduce mortality in patients with AKI, and its use should be carefully considered based on individual patient needs and circumstances 3, 4, 5.

Clinical Practice and Diuretic Use

• A multinational survey of intensive care and nephrology clinicians found that furosemide is the most commonly used diuretic in AKI, and it is often administered intravenously and titrated to a physiologic endpoint of urine output 4.
• Clinicians believe that diuretics can help manage fluid overload and prevent AKI, but they also recognize the need for higher-quality evidence on diuretic use in AKI 4, 7.
• The timing and amount of volume to be administered to prevent AKI and other organ damage is still debated, and aggressive fluid repletion in the early setting may be beneficial, but fluid overload can also be harmful 7.

Future Directions

• Further studies are needed to confirm the efficacy of diuretics in preventing or treating AKI, and to determine the optimal dosing and administration strategies 3, 4, 7, 6, 5.
• Validation studies are required to support the use of continuous infusion of furosemide as a stress test to assess glomerular and tubular functions in AKI patients 6.