A 50-Year-Old Male Presents with Right Foot Pain

With this condition, what three ECG features predict adverse outcomes and what is the expected progression of ECG changes?

This is a case of hyperkalemia as evidenced by the absence of P waves (ie, junctional bradycardia) and peaked T waves. The three ECG features that predict adverse outcomes are:

1. Bradycardia <50 bpm
2. QRS >110 ms
3. Junctional rhythm

Notice that peaked T waves were not found to predict acute adverse outcomes.¹ Table 1 details the expected progression of ECG changes.

What Is the Treatment?

Membrane stabilizers include calcium and hypertonic saline. Intracellular potassium shifters include insulin/glucose, beta-agonists, and sodium bicarbonate in acidotic patients. Potassium eliminators include loop diuretics and kayexalate. New medications to promote gastrointestinal excretion hold promise (patiromer and sodium zirconium cyclosilicate).²

See the video provided by ECG Stampede for detailed analysis.

Pearls for Urgent Care Management

• Electrocardiographic features of hyperkalemia that portend short-term adverse outcomes include bradycardia <50 bpm, QRS >110 ms, and a junctional rhythm.
• Intravenous calcium should be given, if feasible, to anyone with electrocardiographic features that portend adverse outcomes.
• All patients with electrocardiographic changes of hyperkalemia should be transferred to a higher level of care.

REFERENCES

1. Durfey N, Lehnhof B, Bergeson A, et al. Severe hyperkalemia: can the electrocardiogram risk stratify for short-term adverse events? West J Emerg Med. 2017;18(5):963-971.
2. Long B, Warix JR, Koyfman A. Controversies in management of hyperkalemia. J Emerg Med. 2018;55(2):192-205.