Ontario Paramedic Practice Exam

When should a defibrillator be used?

1. During any cardiac episode

2. In cases of ventricular fibrillation or pulseless ventricular tachycardia

3. Only if the patient is responsive

4. When the patient exhibits signs of a stroke

The correct answer is: In cases of ventricular fibrillation or pulseless ventricular tachycardia

A defibrillator should be used specifically in cases of ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). These conditions are life-threatening arrhythmias where the heart's electrical activity becomes chaotic, preventing it from effectively pumping blood. The primary purpose of defibrillation is to deliver an electrical shock to the heart, with the intent of restoring a normal rhythm. Using a defibrillator during other cardiac episodes, such as during a heart attack or congestive heart failure, may not be appropriate, as these situations typically do not involve the need for immediate defibrillation. Defibrillation cannot be administered safely to a responsive patient. If a patient is responsive, they are likely not in need of immediate defibrillation, as they may still have a functional heart rhythm. Furthermore, a defibrillator is not indicated in cases of stroke; the management of stroke is different and involves other immediate interventions such as rapid transport for potential thrombolysis. In summary, the correct application of a defibrillator is crucial in managing specific cardiac emergencies, particularly VF and pulseless VT, where the use of this device may be the difference between life and death.