CRAT Life-Threatening Arrhythmias 3

Question 1

Which electrolyte abnormality is most directly associated with development of torsades de pointes?

Accepted Answer

Hypomagnesemia

Answer

Hypernatremia

Answer

Hypercalcemia

Answer

Hyperphosphatemia

Question 2

In the chain of survival, early defibrillation for VF is critical because VF survival decreases by approximately how much for each minute without defibrillation?

Accepted Answer

7-10% per minute

Answer

1-2% per minute

Answer

15-20% per minute

Answer

50% per minute

Question 3

Accelerated idioventricular rhythm (AIVR) most commonly occurs in which clinical setting?

Accepted Answer

Reperfusion after myocardial infarction

Answer

Digoxin toxicity

Answer

Hyperkalemia

Answer

Complete heart block

Question 4

Hyperkalemia classically produces which ECG change that can progress to ventricular fibrillation?

Accepted Answer

Progressive widening of QRS followed by sine-wave pattern

Answer

ST elevation in multiple leads

Answer

Prolonged QT interval

Answer

Deep Q waves

Question 5

When defibrillating a patient, which safety precaution is most critical immediately before delivering the shock?

Accepted Answer

Ensure all personnel are clear of the patient and bed before discharging

Answer

Apply conductive gel to the patient's chest before paddles

Answer

Verify the patient is unconscious

Answer

Set the defibrillator to synchronized mode

Question 6

A patient's ECG shows wide complex tachycardia at 180 bpm. Which feature most strongly supports a ventricular rather than supraventricular origin?

Accepted Answer

AV dissociation with P waves marching independently through QRS complexes

Answer

Regular R-R intervals

Answer

QRS duration of 120-140 ms

Answer

Rate of 180 bpm