CET Electrolyte Imbalances & ECG Changes 3

Question 1

Which ECG finding is most specific for hypocalcemia compared to other QT-prolonging conditions?

Accepted Answer

Prolonged ST segment with a relatively normal T wave

Answer

Peaked T waves

Answer

Prominent U waves

Answer

Widened QRS complex

Question 2

What is the normal serum potassium reference range?

Accepted Answer

3.5-5.0 mEq/L

Answer

1.5-2.5 mEq/L

Answer

2.0-3.5 mEq/L

Answer

5.5-7.0 mEq/L

Question 3

A patient presents with Chvostek's sign, carpopedal spasm, and muscle cramps. Which ECG finding is most expected?

Accepted Answer

Prolonged QT interval

Answer

Shortened QT interval

Answer

Peaked T waves

Answer

Absent P waves

Question 4

T wave flattening, ST depression, and tall U waves that may fuse with T waves are most associated with which electrolyte imbalance?

Accepted Answer

Hypokalemia

Answer

Hyperkalemia

Answer

Hypercalcemia

Answer

Hypermagnesemia

Question 5

Hypermagnesemia most commonly produces which ECG findings?

Accepted Answer

PR interval prolongation and QRS widening

Answer

Peaked T waves and shortened QT

Answer

Prominent U waves and T wave flattening

Answer

ST elevation and reciprocal changes

Question 6

Which electrolyte condition is associated with a SHORT QT interval and increased risk of ventricular fibrillation?

Accepted Answer

Hypercalcemia

Answer

Hypokalemia

Answer

Hypocalcemia

Answer

Hypomagnesemia

Question 7

When monitoring a hemodialysis patient, the ECG technician should be most alert for which sequence of electrolyte-related changes?

Accepted Answer

Peaked T waves progressing to widened QRS and sine wave pattern

Answer

Shortened PR interval progressing to delta waves

Answer

Prominent U waves progressing to torsades de pointes

Answer

Shortened QT progressing to complete heart block