Optimizing ACEI and ARB Use After Acute Kidney Injury: Best Practices

Introduction

A common scenario leading to kidney injury occurs when patients on ACE inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) start NSAIDs, diuretics, or become dehydrated. Using ACEIs or ARBs after acute kidney injury (AKI) is linked to lower mortality but carries a risk of hyperkalemia. If an ACEI or ARB was stopped due to AKI, carefully weigh the benefits and risks before restarting.

ACEI and ARB Use After Acute Kidney Injury

Generally, avoid restarting ACEIs or ARBs solely for hypertension, as the risks often outweigh the benefits. However, restarting is advisable for patients with heart failure with reduced ejection fraction, recent myocardial infarction, or chronic kidney disease, as these conditions benefit significantly from ACEIs or ARBs.

Wait for serum creatinine (SCr) to stabilize before restarting, which can take up to 6 weeks. Start at a low dose, such as lisinopril (Zestril) 5 mg/day or losartan (Cozaar) 25 mg/day. Check SCr and potassium after 1-2 weeks and titrate up if labs remain stable.

• If SCr increases by more than 30%, halve the dose.
• Hold the ACEI or ARB if SCr stays high or if potassium reaches ≥ 5.5 mEq/L.
• Try restarting when labs improve.
• Once patients are stable on target doses, check labs once or twice a year, or every 3 months in higher-risk patients.

Monitor more frequently if patients start medications that raise potassium, such as spironolactone or TMP/SMX. Encourage patients to stay hydrated and avoid NSAIDs, especially chronically. Educate them to avoid salt substitutes containing potassium.

By following these guidelines, you can optimize patient outcomes while minimizing risks associated with ACEI or ARB therapy post-AKI.

Take-home points

Managing ACEIs or ARBs post-acute kidney injury is crucial...

1. Identify risks of kidney injury when combining ACEIs or ARBs with NSAIDs, diuretics, or dehydration.
2. Use ACEIs or ARBs after AKI to lower mortality, but monitor for hyperkalemia.
3. Avoid restarting ACEIs or ARBs solely for hypertension due to higher risks than benefits.
4. Restart ACEIs or ARBs for conditions like heart failure, recent MI, or chronic kidney disease where they improve outcomes.
5. Wait until serum creatinine stabilizes, which can take up to 6 weeks, before restarting ACEIs or ARBs.
6. Monitor serum creatinine and potassium closely after restarting, adjusting doses as necessary; halve the dose if SCr increases by more than 30% and hold the medication if potassium reaches 5.5 mEq/L or higher.

References

Keywords: ACE inhibitors, Angiotensin II receptor blockers, Acute kidney injury, Hyperkalemia, Serum creatinine, Heart failure, Chronic kidney disease, NSAIDs, Diuretics, Hypertension