Hyperkalemia and Electrocardiogram Manifestations in End-Stage Renal Disease

Area of Science:

• Nephrology
• Cardiology
• Emergency Medicine

Background:

• Hyperkalemia is a frequent, life-threatening metabolic emergency.
• End-stage renal disease (ESRD) patients are at high risk for hyperkalemia.
• Electrocardiogram (ECG) changes are often the first indicator of hyperkalemia.

Purpose of the Study:

• To assess the correlation and diagnostic accuracy of ECG parameters for predicting serum potassium levels in ESRD patients.
• To identify specific ECG findings indicative of hyperkalemia in the ESRD population.

Main Methods:

• Retrospective chart review of 96 ESRD patients with 476 total encounters.
• Analysis of ECGs and serum electrolytes from emergency department visits.
• Linear regression analysis to correlate ECG parameters (T/R ratio, PR interval, QRS duration) with serum potassium concentrations.

Main Results:

• Weak correlations (r2 = 0.02 to 0.12) were found between serum potassium and T/R ratio in V2-V4, PR interval, and QRS duration.
• A QRS duration of 120 ms or greater was the most predictive ECG parameter for hyperkalemia in ESRD patients.
• T/R ratio, PR interval, and QRS duration showed poor predictive value for hyperkalemia in this cohort.

Conclusions:

• A QRS duration ≥120 ms is the most reliable ECG indicator of hyperkalemia in ESRD patients.
• Standard ECG parameters like T/R ratio and PR interval are not accurate predictors of serum potassium levels in ESRD.
• ECG interpretation requires careful consideration of QRS duration in ESRD patients with potential hyperkalemia.