Question

The client is admitted with ventricular fibrillation. The nurse should begin defibrillation by shocking at: A. 360 Joules B. 200 Joules C. 400 Joules D. 600 Joules

Short answer

Answer: 200 Joules.

Step-by-step solution

Identify the correct choice concerning shock energy for defibrillation

In cases of ventricular fibrillation, the initial shock energy for defibrillation should be at 200 Joules, according to the American Heart Association guidelines for CPR and emergency cardiovascular care. Therefore, the correct answer is: B. 200 Joules.

Key concepts

Defibrillation

Defibrillation is a critical medical procedure used to treat life-threatening cardiac arrhythmias, specifically ventricular fibrillation and pulseless ventricular tachycardia. When the heart experiences these conditions, it beats chaotically and cannot pump blood effectively. This irregular heartbeat can lead to cardiac arrest if not corrected promptly.

To restore the heart's normal rhythm, a device called a defibrillator delivers an electric shock to the heart muscle. This shock briefly stops the heart's electrical activity, allowing the heart's natural pacemaker to reset the rhythm.

Defibrillation should be performed as quickly as possible after the onset of ventricular fibrillation to increase the chances of survival. Time is of the essence because every passing minute reduces the likelihood of a positive outcome drastically.

Shock Energy

When using a defibrillator, it's crucial to set the correct shock energy level. The amount of energy delivered by defibrillation is measured in Joules. The selection of the initial shock energy level can significantly impact the success of restoring a normal heart rhythm.

For ventricular fibrillation, the American Heart Association (AHA) recommends starting with a shock energy level of 200 Joules. This amount is typically sufficient to disrupt the erratic electrical activity of the heart, allowing it to revert to a normal rhythm.

In some cases, if the first shock is unsuccessful, subsequent shocks may be delivered at the same or higher energy levels. It's essential for medical professionals to be familiar with the guidelines and the specific defibrillator being used, as types and settings may vary.

American Heart Association guidelines

The American Heart Association (AHA) provides vital guidelines for medical professionals on various emergency procedures, including defibrillation. These guidelines are periodically updated to reflect the latest research and technological advances.

For ventricular fibrillation, the AHA guidelines suggest initiating defibrillation with specific energy settings. The initial shock should be set to 200 Joules, as this has been shown to be effective for many patients. These guidelines are widely accepted and followed in medical practice to ensure consistency and improve patient outcomes.

Additionally, the AHA guidelines cover other aspects of emergency cardiovascular care like algorithms for basic and advanced life support, recognizing the symptoms of a heart attack, and recommendations for bystander intervention.

CPR

Cardiopulmonary resuscitation, or CPR, is a life-saving technique used in emergencies when someone's heartbeat or breathing has stopped, such as in cases of ventricular fibrillation. CPR involves chest compressions and rescue breathing (or just compressions) to keep oxygen-rich blood circulating to vital organs until further treatment, such as defibrillation, can be administered.

High-quality CPR is critical for increasing the chances of survival and neurological outcomes after cardiac arrest. It's often performed in conjunction with defibrillation in cases of sudden cardiac arrest due to ventricular fibrillation.

Current guidelines emphasize "hands-only" CPR for untrained bystanders, focusing on chest compressions performed at a rate of 100 to 120 per minute. For trained responders, CPR includes rescue breaths and defibrillation when available. Quality and timely CPR can create a significant difference in survival rates and recovery.