Guide Pharmacists to Manage Hyperkalemia in Heart Failure Patients

Overview

Managing hyperkalemia (HK) in HF requires a structured approach based on serum K levels and the patient’s clinical condition. See our note "Debunking Hyperkalemia Myths: What Clinicians Need to Know".

NPS-adv

Clinical practice

In all patients

For K > 5.4 mmol/L, evaluate for contributing factors such as over-diuresis or hypovolemia. Review non-selective beta-blockers, which can raise K levels. Continue them in HFrEF due to their prognostic benefits but reconsider in HFpEF. Stop K supplements, K-sparing diuretics (e.g., amiloride, triamterene), NSAIDs, trimethoprim, and sodium substitutes. Check for digoxin toxicity and advise a low-K diet.

Mild HK (5.5–5.9 mmol/L)

• Clinically stable, no AKI: Increase biochemical monitoring frequency but continue RAAS inhibitors (RAASi). Consider reducing the dose.
• Clinically unstable (sepsis, hypovolemia, or AKI): Hold RAASi until the underlying issue resolves. Restart when K <5.5 mmol/L.

Moderate HK (6–6.4 mmol/L)

• Clinically stable, no AKI: Stop RAASi and repeat K testing. Restart when K < 5.5 mmol/L at a lower dose. Reintroduce one drug at a time if the patient was on multiple RAASi (e.g., ACEI/ARB/ARNI + MRA), with close monitoring.
• Clinically unstable: Hold RAASi until sepsis, hypovolemia, or AKI resolves. Restart therapy carefully when K < 5.5 mmol/L.

Severe HK (>6.5 mmol/L)

• Clinically stable: Admit for urgent K-lowering treatment. Stop RAASi and repeat bloodwork after 24 hours. Restart RAASi when K < 5.5 mmol/L at a lower dose, reintroducing one medication at a time with biochemical monitoring.
• Clinically unstable: Discontinue RAASi and address the underlying issues (e.g., sepsis, hypovolemia, or AKI). Restart when K < 5.5 mmol/L, reintroducing drugs one at a time.

Decompensated HF

• Without AKI: Do not stop RAASi but consider dose reduction. Treat congestion with loop diuretics or a combination of loop and thiazide diuretics.
• With AKI: Reduce or hold RAASi depending on K levels. Restart at a lower dose when K < 6 mmol/L, reintroducing one drug at a time with monitoring.

Proper monitoring, dietary counseling, and gradual reintroduction of RAASi can minimize HK risks while optimizing HF management.

NPS-adv

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References

1. Clark AL, Kalra PR, Petrie MC, Mark PB, Tomlinson LA, Tomson CR. Change in renal function associated with drug treatment in heart failure: national guidance. Heart. 2019;105(12):904-910.
2. Heart failure management in frail older people. (2022, December 2). SPS - Specialist Pharmacy Service. https://www.sps.nhs.uk/articles/heart-failure-management-in-frail-older-people.

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