Q: Usually which of the following is the first EKG sign in hyperkalemia?
A) A tall peaked T wave with shortened QT interval
B) Progressive lengthening of the PR interval
C) Progressive lengthening of the QRS duration
C) Sine wave
D) Ventricular standstill
A tall peaked T wave with shortened QT interval is the earliest sign. It is followed by progressive lengthening of the PR interval and QRS duration. As hyperkalemia worsen, P wave progressively disappear, the QRS widens towards a sine wave. Eventually, ventricular standstill with a flat line is the final thing!
MOST IMPORTANT THING TO REMEMBER - The progression and severity of ECG changes in hyperkalemia do not correlate with the serum potassium concentration, and there is no table to co-relate.