Association between hyperkalemia at critical care initiation and mortality

Area of Science:

• Critical care medicine
• Clinical chemistry
• Epidemiology

Background:

• Potassium levels are crucial physiological parameters.
• Electrolyte disturbances can significantly impact patient outcomes in critical care settings.

Purpose of the Study:

• To investigate the association between potassium concentration at the initiation of critical care and all-cause mortality.
• To determine if elevated potassium levels predict mortality in critically ill patients.

Main Methods:

• Retrospective observational study of 39,705 adult patients admitted to critical care.
• Potassium concentration categorized into groups (4.0-4.5 to ≥6.5 mEq/l).
• Logistic regression used to analyze mortality at 30 days, 90 days, 365 days, and in-hospital mortality.

Main Results:

• Potassium concentration was a strong predictor of 30-day all-cause mortality.
• A significant risk gradient was observed across increasing potassium groups (e.g., OR 1.25 for 4.5-5.0 mEq/l to OR 1.72 for >6.5 mEq/l).
• Similar associations were found for in-hospital, 90-day, and 365-day mortality; the association was not significant if hyperkalemia decreased by ≥1 mEq/l within 48 hours.

Conclusions:

• Potassium level at critical care initiation is robustly associated with the risk of death.
• Even moderate increases in potassium above normal levels indicate a heightened risk of mortality.
• Monitoring and management of potassium levels are critical in critical care.