When someone experiences sudden cardiac arrest, every second matters. According to the 2024 Cardiac Arrest Registry to Enhance Survival (CARES) report, approximately 263,711 out-of-hospital cardiac arrests occur annually in the United States. Knowing how to use a defibrillator can mean the difference between life and death. Research shows that immediate CPR combined with defibrillator use can double or even triple survival rates, yet only 41.7% of cardiac arrest victims receive bystander intervention.
What is a Defibrillator?
A defibrillator is a portable, lightweight medical device that delivers an electric shock to the heart when it detects an abnormal rhythm. The device analyzes the heart’s electrical activity and restores normal rhythm during sudden cardiac arrest. When the heart stops beating regularly due to ventricular fibrillation or ventricular tachycardia, a defibrillator provides the critical intervention needed to restart coordinated heart function.
The American Heart Association identifies defibrillation as a vital link in the Chain of Survival. For every minute without defibrillation, survival chances decrease by 7-10%. This dramatic decline underscores why automated external defibrillators (AEDs) are now commonplace in airports, schools, shopping centers, and workplaces across the country.
How Defibrillators Work?
Defibrillators work by delivering controlled electrical energy through electrode pads placed on the victim’s bare chest. The device first analyzes the heart’s rhythm to determine if a shock is appropriate. Modern AEDs use sophisticated algorithms to detect shockable rhythms like ventricular fibrillation. The electrical current temporarily stops the chaotic electrical activity in the heart, allowing the heart’s natural pacemaker to reestablish an effective rhythm.
According to the 2025 American Heart Association Guidelines, defibrillation within 3-5 minutes of collapse can produce survival rates as high as 49-75%. Studies demonstrate that survival from cardiac arrest doubles when bystanders use a publicly available defibrillator rather than wait for emergency responders.
How to Use a Defibrillator Step by Step
Using an automated external defibrillator is simpler than most people realize. The device provides voice prompts and visual instructions throughout the process. Here’s the complete step-by-step guide for defibrillator operation:
Step 1: Assess the Scene and Check Responsiveness
First, ensure the environment is safe for you and the victim. Check if the person is responsive by tapping their shoulder firmly and shouting. Look for signs of breathing and check for a pulse for no more than 10 seconds. If the person is unresponsive, not breathing normally, or has no pulse, immediate action is required.
Step 2: Call for Emergency Help
Immediately call 911 or your local emergency number. If you’re with others, designate someone to make the call while you begin assistance. Use your phone’s speaker mode so you can receive guidance from the emergency dispatcher while helping the victim.
Step 3: Retrieve the AED
Send someone to get the nearest defibrillator or retrieve it yourself if you’re alone. Many public locations have AED cabinets with clear signage. The 2024 CARES report reveals that over 15% of cardiac arrests occur in public locations, making public access defibrillator programs crucial.
Step 4: Turn On the Defibrillator
Power on the AED device. Most units turn on automatically when you open the case, while others have a power button. Once activated, the defibrillator will provide clear audio instructions guiding you through each step.
Step 5: Expose and Prepare the Chest
Remove all clothing from the victim’s chest. The chest must be completely bare and dry for the electrode pads to make proper contact. If the chest is wet from sweat or water, quickly dry it. Remove any medication patches and wipe away excess chest hair if necessary for pad adherence.
Step 6: Attach the Electrode Pads
Peel the backing from the adhesive electrode pads. Place one pad on the upper right chest below the collarbone and the other on the lower left side below the armpit. Follow the diagram on the pads showing proper placement. The 2025 AHA Guidelines specify that for anyone 8 years or older, use adult defibrillator pads.
Step 7: Allow Rhythm Analysis
Once the pads are attached, the defibrillator will automatically analyze the heart rhythm. Do not touch the victim during this critical analysis period. The device will announce when it’s analyzing. This process typically takes 5-15 seconds.
Step 8: Deliver the Shock if Advised
If the defibrillator determines a shock is needed, it will advise you to deliver it. Ensure nobody is touching the victim. Loudly announce “Clear!” and visually confirm that no one is in contact with the victim. Press the shock button when prompted. Modern automated defibrillators may deliver the shock automatically without requiring you to press a button.
Step 9: Resume CPR Immediately
After the shock is delivered, immediately begin chest compressions. Push hard and fast in the center of the chest at a rate of 100-120 compressions per minute with a depth of at least 2 inches. Continue CPR for about 2 minutes until the defibrillator prompts another rhythm analysis.
Step 10: Continue Until Help Arrives
Follow the defibrillator prompts and continue the cycle of CPR and defibrillation until emergency medical services arrive or the victim begins breathing normally. Keep the electrode pads attached and the defibrillator turned on throughout the process.
Types of Defibrillators
Understanding the different defibrillator types helps you recognize which device you might encounter during an emergency situation.
Automated External Defibrillators (AEDs)
AEDs are the most common public access defibrillators. These portable devices automatically analyze heart rhythms and provide voice instructions. Semi-automated AEDs require the user to press a button to deliver the shock, while fully automated models deliver the shock automatically after detecting a shockable rhythm. The FDA approved fully automated defibrillators beginning in 2017.
AEDs are designed for use by anyone, regardless of medical training. The devices cannot be made to shock someone who doesn’t need defibrillation. According to current AHA standards, AEDs should be accessible within 3-5 minutes of any location to maximize survival chances.
Manual External Defibrillators
Manual external defibrillators are used primarily by healthcare professionals in hospitals and ambulances. These devices require the operator to interpret the heart rhythm and select the appropriate energy level for defibrillation. The 2025 AHA Guidelines recommend manufacturer-set doses of 120-200 joules for biphasic defibrillators and 360 joules for monophasic models.
Healthcare providers trained in Advanced Cardiovascular Life Support (ACLS) use manual defibrillators as part of comprehensive cardiac arrest management protocols.
Implantable Cardioverter Defibrillators (ICDs)
ICDs are surgically implanted devices for patients at high risk of sudden cardiac death. These small devices continuously monitor heart rhythm and automatically deliver shocks when dangerous rhythms are detected. ICDs have significantly improved long-term survival for patients with certain cardiac conditions.
Wearable Cardioverter Defibrillators (WCDs)
Wearable cardioverter defibrillators are vest-like devices worn by patients who have a temporary increased risk of sudden cardiac arrest. These devices protect while patients await permanent ICD implantation or during recovery from cardiac procedures.
Critical Defibrillator Safety Considerations
When using a defibrillator, several safety factors ensure effective operation and protect both the victim and rescuer.
Environmental Hazards
Never use a defibrillator in standing water or when the victim is lying in water. Water conducts electricity and creates shock hazards. If the victim is in water, move them to a dry surface before applying the defibrillator. Remove wet clothing and dry the chest thoroughly.
Metal Surfaces and Jewelry
While metal jewelry doesn’t need removal, medication patches must be removed from the chest. If the victim is lying on a metal surface, defibrillation can proceed safely as long as no one is touching the victim or the metal surface during shock delivery.
Pacemakers and ICDs
If you notice a lump under the skin on the upper chest indicating an implanted device, place the defibrillator pads at least one inch away from the device. The presence of implanted cardiac devices doesn’t prevent external defibrillator use.
Pediatric Considerations
For children under 8 years old or weighing less than 55 pounds, use pediatric defibrillator pads if available. If only adult pads are available, they can be used. Never use pediatric pads on adults, as they don’t deliver sufficient energy.
Why Defibrillator Training Matters
While AEDs are designed for intuitive use, proper training significantly improves response confidence and effectiveness. Research on workplace cardiac arrests shows that only 50% of people can locate an automated external defibrillator at work, yet approximately 10,000 workplace cardiac arrests occur annually in the United States.
The American Heart Association reports that bystander CPR was initiated in only 41.7% of out-of-hospital cardiac arrests reported in 2024. Training programs address this gap by teaching recognition of cardiac arrest, proper CPR technique, and confident defibrillator operation.
Workplace and Community Training Benefits
Organizations that implement comprehensive training programs see dramatic improvements in emergency response. A two-year study of young athletes showed that survival rates reached 83% when certified personnel were present and 89% when on-site AEDs were immediately available.
Training also addresses the psychological barriers that prevent bystanders from acting. Studies reveal that trained individuals are significantly more likely to recognize cardiac arrest symptoms, call for help promptly, and begin lifesaving interventions without hesitation.
Take Action: Protect Your Community
Sudden cardiac arrest can happen to anyone, anywhere, at any time. Being prepared to use a defibrillator effectively can save the life of a family member, coworker, or stranger. The confidence gained through proper training transforms bystanders into lifesavers.
Don’t wait until an emergency strikes to learn these vital skills. Professional training ensures you can act quickly and correctly when seconds count. Comprehensive courses combine hands-on practice with current American Heart Association guidelines, giving you the knowledge and confidence to respond effectively.
Ready to become a certified lifesaver? CPR Kansas City is an American Heart Association training site offering initial certifications and renewal courses in BLS for Healthcare Providers, ACLS, PALS, and CPR and First Aid. All classes are stress-free and hands-on, providing the practical experience you need to respond with confidence.
Whether you need CPR certification in Kansas City or BLS certification in Kansas City, our expert instructors ensure you gain life-saving skills that make a real difference. Contact CPR Kansas City today and take the first step toward being prepared to save a life.
