1a = Talk and peak Y wave.  1b = Narrow T wave.  1c = slur J point
Hyperkalemia (Case 1). Pattern of stage 1.
Patient. 41 yo diabetic female on chronic peritoneal dialysis admitted with diabetic ketoacidosis. Her initial potassium level was 6.6

Stage 1

>5.5 mM - T wave.

- Tall and peak (1a) with narrow T wave (1b)
- ST segment is concaved
- Slur J point (1c)
Occurs in 1/4 of hyperkalemia patient.

Stage 2

>6.5 mM - QRS change.

- Widening of both initial and terminal portion due to slow conduction in the ventricles.
- Progressive widening with higher serum K+ level and may reach dying heart pattern.
- There is only rough correlation between K+ level and QRS width.

Stage 3

>7.0 mM - P wave

- Amplitude decreases and duration increases due to slower conduction in the atria.
- Invisible when K+ is >8.0 mM (Sinoventricular conduction or displacement of the pacemaker into junctional or Purkinje fibers).
Stage 4 . >10.0 mM - Irregular wide QRS rhythm
Stage 5 . 12-14 mM - Ventricular asystole or ventricular fibrillation
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