Baseline Potassium Levels and Their Association With Electrocardiograph Abnormalities in Hyperkalaemia

Area of Science:

• Cardiology
• Nephrology
• Internal Medicine

Background:

• Hyperkalaemia is a life-threatening condition associated with cardiac arrhythmias.
• Electrocardiograph (ECG) abnormalities are linked to hyperkalaemic serum potassium (HK) levels.
• The relationship between baseline serum potassium (BK) levels and ECG changes in hyperkalaemia is not well understood.

Purpose of the Study:

• To investigate the association between baseline serum potassium (BK) levels, hyperkalaemic serum potassium (HK) levels, and the development of ECG abnormalities in patients with severe hyperkalaemia.
• To determine the predictive value of both BK and HK levels, as well as the difference between them, for ECG changes.

Main Methods:

• Retrospective cohort study of outpatients with severe hyperkalaemia (serum potassium ≥ 6.5 mEq/L).
• Baseline potassium (BK) levels were averaged from the three most recent pre-episode values.
• Hyperkalaemia-associated ECG changes were compared to normokalaemic recordings.

Main Results:

• The study included 283 patients (median age 74 years; 31.8% female).
• Both below-median BK levels (OR, 4.61) and above-median HK levels (OR, 2.28) were associated with increased odds of ECG changes.
• A greater BK-HK level difference showed a strong association with ECG abnormalities (OR, 6.85).

Conclusions:

• Both baseline and hyperkalaemic serum potassium levels are significant predictors of ECG abnormalities.
• The magnitude of potassium increase, indicated by the BK-HK difference, is a critical factor in predicting ECG changes.
• Clinicians should consider both baseline and acute potassium levels when managing hyperkalaemia.