From the Guidelines
Optimizing volume status with intravenous loop diuretics, such as furosemide, is crucial in managing acute on chronic kidney injury during congestive heart failure exacerbation, as it helps reduce morbidity and mortality by alleviating fluid overload and improving renal perfusion. The initial intravenous dose of loop diuretics should equal or exceed the patient's chronic oral daily dose, with serial assessments of urine output and signs of congestion to guide dose adjustments 1.
Key Considerations
- Intravenous loop diuretics: Furosemide 40-80mg IV (or 2.5 times the oral dose) every 12-24 hours, with dose adjustments based on response, is recommended for managing fluid overload in CHF patients with AKI on CKI 1.
- Continuous infusion: Consider continuous infusion at 5-10mg/hour if bolus therapy is ineffective, as it may provide a more consistent diuretic effect and help manage refractory congestion 1.
- Nephrotoxic medications: Temporarily holding potentially nephrotoxic medications, including ACE inhibitors, ARBs, NSAIDs, and metformin, may help mitigate further kidney injury and allow for recovery of renal function 1.
- Fluid balance and perfusion: Monitoring fluid balance closely with daily weights and strict intake/output measurements, and ensuring adequate perfusion by maintaining mean arterial pressure above 65mmHg using vasopressors if necessary, are critical components of managing AKI on CKI in CHF patients 1.
- Electrolyte and kidney function monitoring: Checking basic metabolic panel daily to monitor electrolytes and kidney function is essential for early detection of potential complications and guiding adjustments in treatment 1.
- Ultrafiltration or hemodialysis: Consider ultrafiltration or hemodialysis for refractory volume overload or severe electrolyte abnormalities, as these interventions can help rapidly correct fluid and electrolyte imbalances and improve renal function 1.
Pathophysiology and Treatment Goals
The underlying pathophysiology of AKI on CKI in CHF involves reduced cardiac output leading to decreased renal perfusion, while venous congestion increases renal back-pressure, both impairing kidney function. Treatment aims to improve cardiac output while reducing congestion, allowing kidneys to recover function as the cardiorenal syndrome improves. By prioritizing volume status optimization, careful medication management, and close monitoring of fluid balance and perfusion, clinicians can help reduce morbidity and mortality in patients with AKI on CKI during CHF exacerbation.
From the FDA Drug Label
In patients with hepatic cirrhosis and ascites, furosemide therapy is best initiated in the hospital. If increasing azotemia and oliguria occur during treatment of severe progressive renal disease, furosemide should be discontinued. Furosemide is indicated in adults and pediatric patients for the treatment of edema associated with congestive heart failure, cirrhosis of the liver, and renal disease, including the nephrotic syndrome
Treating acute on chronic kidney injury in the setting of CHF exacerbation with furosemide (IV) may be considered, as it is indicated for the treatment of edema associated with congestive heart failure. However, caution is advised in patients with severe progressive renal disease, as increasing azotemia and oliguria may occur, requiring discontinuation of furosemide 2. Close monitoring is necessary during the period of diuresis to prevent sudden alterations of fluid and electrolyte balance 2.
- Key considerations:
- Furosemide is indicated for edema associated with congestive heart failure
- Caution is advised in patients with severe progressive renal disease
- Close monitoring is necessary during diuresis
- Discontinue furosemide if increasing azotemia and oliguria occur 2
- Parenteral therapy should be replaced with oral furosemide as soon as practical 2
From the Research
Treatment of Acute on Chronic Kidney Injury in CHF Exacerbation
- The management of heart failure patients with chronic kidney disease (CKD) is complex and requires a multidisciplinary approach 3.
- The use of β-blockers, angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, angiotensin receptor neprilysin inhibitors, and sodium-glucose cotransporter inhibitors has been shown to improve outcomes in patients with heart failure with reduced ejection fraction (HFrEF) and mild-to-moderate CKD 3.
- However, the use of these therapies is often limited by concerns about hyperkalemia and worsening kidney function 3.
- High-dose and combination diuretic therapy may be necessary to manage fluid overload in patients with CKD, but can be complicated by worsening kidney function and electrolyte imbalances 3.
- The furosemide stress test has been shown to be predictive of worsening acute kidney injury in critically ill patients 4.
Diuretic Therapy
- Diuretic therapy is a key component of the management of acute heart failure, but can be complicated by worsening kidney function and electrolyte imbalances 3, 5.
- The use of loop diuretics, such as furosemide, is common in the treatment of heart failure, but can be associated with acute kidney injury, particularly when used in combination with other medications such as angiotensin-converting enzyme inhibitors 6.
- The furosemide stress test can be used to predict the progression of acute kidney injury in critically ill patients 4.