Automated External Defibrillators AEDs Appendix A Topic Overview

Automated External Defibrillators (AEDs) Appendix A

Topic Overview – Rationale for early defibrillation. – When defibrillation to appropriate. – How defibrillation works. – General steps for the use of an automated external defibrillator (AED).

AEDs • The heart's electrical system – Conduction system • Originates in the atria – sinoatrial node (SA) – atrioventricular node (AV) • Ends in the ventricles

AEDs – Cardiac Rhythms • • • Normal sinus rhythm Ventricular fibrillation (V-fib) Ventricular tachycardia (V-tach) Asystole Pulseless electrical activity (PEA)

AEDs • Defibrillation – Protocol for using an Automated External Defibrillator (AED) – When the Heart Fails • Early defibrillation provides the best chance for survival • Rhythms which will respond to defibrillation – Ventricular tachycardia (V-tach) – Ventricular fibrillation (V-fib) – Coarse & Fine • Other abnormal heart rhythms will Not respond to defibrillation

AEDs • The Role of CPR – Begun immediately circulates oxygenated blood • Appears to contribute to preserving brain function – Alone CAN NOT maintain or convert V-fib to a normal sinus rhythm • CPR & defibrillation when done together significantly enhance chances of survival • Delaying CPR or defibrillation reduces chances of survival.

AEDs • Time Line - % Survival – No treatment - 0% – Delayed Defibrillation - 2% – Early CPR, Delayed Defibrillation - 8% – Early Access, Early CPR, Early Defibrillation - 20% – Early Access, Early CPR, Early Defibrillation, Early ACLS - 30 -40%

AEDs • Defibrillation – IS NOT intended to restart a heart – IS intended to briefly disrupt abnormal electrical activity (V-tach/V-fib) – If not corrected abnormal heart rhythms will lead to asystole – Asystole is NOT correctable by defibrillation • Requires CPR

Analysis of Cardiac Rhythm AEDs are extremely accurate in distinguishing between shockable and non-shockable rhythms.

Inappropriate Shocks Very rarely does AED computer make a mistake. AED-related errors are almost always human. • Not clearing patient • Not stopping ambulance to analyze rhythm

AEDs • Advantages – Requires less training than traditional manual defibrillators – Are less expensive than manual units – Are easier to use than manual units – Can enable 1 st responders to rapidly initiate defibrillation

AEDs – Can automatically recognize a shockable heart rhythm • Can deliver up to three stacked shocks • Delivers subsequent shocks at max joules • All units set to deliver up to 9 shocks – Parker Units are programmed to deliver up to 12 shocks

AEDs • Use and operation (2 Rescuers) – All AEDs can be operated by flowing these basic steps: • Confirm cardiac arrest (unresponsive, not breathing, no pulse) • Set up AED as partner starts CPR • Turn on power • Place one pad to upper right chest, second pad over lower left ribs • Stop CPR, Stay clear of patient

AEDs • Use and operation (2 Rescuers) • If shock advised, say “I’m clear, your clear, we’re all clear”, then press shock button. • Resume CPR for two minutes • After two minutes of CPR, clear patient and repeat sequence of analysis followed by one shock if indicated.

AEDs • Use and operation (1 Rescuer) – Witnessed Arrest • Establish responsiveness, contact 911, check pulse, turn on AED and apply pads. • Deliver 1 shock if indicated • Perform 2 minutes of CPR (5 cycles) • Repeat shock and CPR as indicated – Unwitnessed Arrest

AEDs • Use and operation (1 Rescuer) – Un. Witnessed Arrest • Establish responsiveness, contact 911, check pulse • Perform 2 minutes of CPR (5 cycles) • Turn on AED and apply pads. • Deliver 1 shock if indicated • Perform 2 minutes of CPR (5 cycles) • Repeat shock and CPR as indicated

AEDs • Precautions – Do not clean chest with alcohol pads – STAND CLEAR of victim while unit is analyzing the rhythm and defibrillating – Do not attempt to use in a moving vehicle – Do not defibrillate a victim who is in water • When using around pool, place victim in a dry area by sure feet are dry • Keep all bystanders sway from puddles of water

AEDs • Precautions – Do not defibrillate a victim in contact with metal – Do not defibrillate a victim who is less than 1 YOA (AHA). – Avoid radio transmissions or cell phone usage within 6 feet when using an AED

AEDs • Precautions – Keep delivery devices with flowing oxygen away from the victim – If you suspect a pacemaker, do not place the AED pads directly over the top – Be sure to remove any nitroglycerin patches • Wipe off adhesive with alcohol prep pad and then dry completely to remove alcohol

AEDs • Precautions – If victim is suffering from hypothermia, deliver no more than three shocks, continue CPR even if the AED prompts you to shock again. • Victim may be severely bradycardic – AED will not recognize

Early Defibrillation Program • Establishing a Program – Must consider: • Size, age & location of the populations to be served • The number of trained responders • The response times of first responders and more advanced personnel • The number of AEDs available • Where the AEDs should be placed within the community or facility

Early Defibrillation Program • Establishing a Program – Must consider: • Commitment to the program from the local medical director and EMS • State requirements for purchase, ownership, use and certification