Can Angiotensin Receptor Blockers (ARBs) be given in patients with acute renal insufficiency?

ARBs Should Not Be Given in Acute Renal Insufficiency

Angiotensin Receptor Blockers (ARBs) should be avoided in patients with acute renal insufficiency due to their potential to worsen kidney function and increase risk of hyperkalemia.

Mechanism and Risks

ARBs work by blocking the renin-angiotensin system, which can have detrimental effects in acute kidney injury:

• ARBs can cause acute renal failure in patients with severe bilateral renal artery stenosis 1
• They increase the risk of hyperkalemia, especially in patients with compromised renal function 2, 3
• During acute illness, ARBs can reduce glomerular filtration pressure, potentially worsening renal function 4

Evidence-Based Recommendations

When to Discontinue ARBs

ARBs should be discontinued in patients with:

• Acute kidney injury or acute renal insufficiency 4
• Volume depletion or hypovolemia 3
• Severe bilateral renal artery stenosis 3
• Serum potassium levels >5.5 mmol/L 1

Monitoring and Management

If a patient is already on ARB therapy:

• Monitor renal function and serum electrolytes closely 3
• If creatinine rises >20% from baseline, consider discontinuation 5
• Volume status should be optimized before restarting ARBs 1
• Only restart ARBs when GFR has stabilized and volume status is optimized 1

Special Considerations

Risk Factors for ARB-Induced Renal Dysfunction

Patients at higher risk for ARB-induced renal dysfunction include:

• Elderly patients (>65 years) 6
• Those with bilateral renal artery stenosis 7
• Patients with concomitant use of diuretics or NSAIDs 2
• Patients with heart failure and compromised renal function 3

Combination Therapy Risks

• Avoid dual blockade of the renin-angiotensin system (combining ARBs with ACE inhibitors) as this increases risk of hyperkalemia and acute kidney injury 2
• The "triple whammy" combination of NSAIDs, diuretics, and ARBs significantly increases AKI risk 4

Resuming ARB Therapy

When considering restarting ARBs after an episode of acute renal insufficiency:

1. Ensure patient is euvolemic
2. Verify renal function has returned to baseline
3. Start at a lower dose and titrate slowly
4. Monitor renal function and electrolytes within 1 week of restarting

Conclusion

While ARBs provide long-term benefits in chronic kidney disease and heart failure, they should be temporarily discontinued during episodes of acute renal insufficiency until renal function stabilizes and volume status is optimized. The risk of worsening renal function and hyperkalemia outweighs potential benefits during acute kidney injury.