Automated External Defibrilators and CPR Skills
Automated External Defibrillators (AEDs) are the latest, most important, advancement in sudden cardiac arrest response. They are amazing little gadgets that pretty much anyone can operate with little aed training and they are popping up all over the place, from schools to churches to health clubs to homes.
Ventricular Fibrillation (VF) is an electrical abnormality where the heart stops pumping because the electrical impulses in the heart are out of synch, causing it to quiver instead of beat. I like the analogy of this being like an hysterical person who is screaming and crying and beyond reason – a rude slap in the face shocks them into gaining composure. If VF is treated quickly, the heart can get back to work just fine – if not treated, VF degrades to something called ‘asystole’ which is generally fatal.
Importance of Rapid Response
If a VF victim gets his heart pattern restored immediately following a sudden cardiac arrest, he has about a 2/3rds chance of recovery. Every minute that revival is delayed, the chances drop until there is little hope after 10 minutes.
CPR is not a means to revival. CPR is a temporary bandaid to keep oxygen flowing to the brain until a way to revive the victim is ready. Not many years ago, that means of revival was only available in hospitals, operated by highly trained medical personnel. Manual external defibrillators are used to apply an electric shock to victims in an attempt to restore a useful pattern to the heart muscle. Doing CPR in the field while a means to revival is bolted to the floor in a hospital does the victim no good. The next step was to make the defibrillators portable. These portable defibrillators were installed in ambulances. With this advancement, CPR in the field made sense. If a person could keep blood flowing until the ambulance arrived, there was a chance of recovery. But, arrival times could be 15 minutes, 30 minutes, or longer.
AEDs Arrive Around 1980, the AED (automated external defibrillator) debuted. The ‘automated’ part is what is really exciting. Now people with only minimal training can successfully revive VF victims in the field, even before Emergency Medical Services personnel arrive. An AED can be down the hall, just 1 or 2 minutes away, so chances for revival are way up. The AED can automatically analyze the victim and decide if a shock is required or not. The operator just needs to follow simple commands from the AED and push the shock button when/if told to push it.
AEDs are nearly error-free, weigh under 5 lbs, are simple to learn and operate, are safe, can be stored anywhere, and they work! There are a few different types of AEDs and improvements are being made all the time. Many people have home defibrillators and there are personal AEDs that are worn under clothing and automatically analyze and apply shock as needed.
Using an AED
As soon as a victim is encountered and it is determined that they are unresponsive, three things need to happen:
- Someone calls 000 if a phone is available
- Someone retrieves the AED if one is available
- Someone checks for breathing and circulation and begins CPR if needed
- That works fine if you have at least 3 people on the scene.
- If there are only 2 people, one calls 000 and gets the AED while the second begins CPR.
- If you are all alone, you should do them all in the order listed even if it means leaving the victim – call 000, get the AED, and then check for breathing.
If the victim is not breathing, follow these steps to perform CPR with an AED:
- Position the victim on his back.
- Tilt head back and lift chin. Check for breathing for no more than 10 seconds.
- If the victim is not breathing, give 2 rescue breaths.
- Check for signs of circulation. If there is no circulation, then the heart is not pumping.
- Turn on the AED and follow audio commands.
- Open the victim’s shirt and wipe his chest dry of sweat or water.
- Attach one pad to the victim’s upper right chest and one to the lower left side. The pads will be labelled with a picture of where they go.
- Plug the wire from the pads into the AED if they are not already attached.
- Make sure no one is touching the victim so the AED can analyze correctly.
- Push the ‘Analyze’ button or let the AED automatically begin its analysis. Just wait for the analysis to complete.
If the AED determines a shock is required:
- Keep everyone clear of the victim.
- Press the ‘shock’ button.
- Let the AED reanalyze.
If the AED determines no shock is needed:
- Check for a pulse.
- If you can not find a pulse and the victim is not breathing, perform CPR until the AED reanalyzes.
- If there is a pulse but no breathing, then perform rescue breathing and make sure the breaths raise the chest.
- If there is a pulse and breathing, place the victim in a recover position and monitor them.
Once you have attached the AED to a victim, do not remove it. It will continue to analyze and if the victim lapses again, the AED will recommend a shock if needed. When Emergency Medical Services personnel are on the scene, they can remove it.
AED Q & A
Can I hurt someone by using an AED on them? No, the AED automatically analyzes and determines if a shock is required. If you have determined to use an AED, then the person is essentially dead already anyway. You should participate in some AED training before using an AED.
Can I get sued for using an AED? Yes, you can get sued for any reason. Chances of you losing a suit because you used CPR and an AED attempting to revive someone are very close to zero. Finding ‘Good Samaritans’ at fault is very rare.
WHAT DOES CPR STAND FOR?
Cardio = HEART
Pulmonary = LUNGS
Resuscitate = REVIVE
Cardio-Pulmonary Resuscitation = Reviving the Heart and Lungs
Cardio = HEART
Your heart is a big, strong muscle that expands and contracts more than 60 times a minute without you even thinking about it. It is automatically driven by electrical impulses and runs 24 hours a day, 7 days a week, with no vacation time. That’s around 33 million beats a year!
Your heart has a simple, but important job. It pumps oxygen-rich blood from the lungs out to the rest of your body. If your heart stops pumping, oxygen does not reach vital organs and they stop working. That’s when you get in trouble.
Pulmonary = LUNGS
You breathe about 15 to 25 times each minute and every breath you take brings oxygen into your lungs and gets rid of carbon dioxide. Your lungs function automatically just like your heart – you don’t have to think about breathing, it just happens.
Oxygen is important to your body because it gets combined with sugar to burn as fuel. There is very little oxygen stored in your body’s tissues so it needs to be replenished often. (There is a big supply of sugar so you can go a long time without eating.)
If your body stops bringing air with oxygen in it into your lungs or your heart stops circulating the oxygen-rich blood to your organs, then bad things start to have real fast. When the oxygen runs out, the body only has a few minutes in an anaerobic state before cells start to die and brain damage results. Typically, cells last 4 to 6 minutes before they begin to die and, after 10 minutes, the body is unrevivable.
Some things that might prevent oxygen from reaching the cells of your body:
- Choking – something blocks the path for air to reach the lungs.
- Poisoning – some other gas takes the place of oxygen, such as carbon monoxide.
- Drowning or suffocation – there is no air available to breathe in.
- Electric shock – an electric impulse disrupts the normal heart pattern and causes it to stop.
- Heart attack – the heart stops beating. Oxygen is available in the blood in the lungs, but the heart is not moving it around.
- Ventricular Fibrillation (VF) – the heart gets out of synch and quivers instead of pumps, causing cardiac arrest. This is the most common cause of sudden cardiac arrest and is what Automated External Defibrillators (AEDs) are for.
CardioPulmonary Resuscitation (CPR) is a combination of simulating the breathing of the lungs and the pumping of the heart. You should know that CPR is effective less than 30% of the time. Does that mean it is futile? No way! The types of victims you will probably run into will most likely be on the high end of the probability scale. Recovery rates for people already in the hospital are about half that and less than 5% for elderly people with other medical problems. So, even though there’s a good chance your efforts will fail, that person has a 0% chance if you do nothing. Let’s talk about what CPR is and how it works.
CPR is made up of two parts: Rescue Breathing and Chest Compresssions
Rescue Breathing You exhale air from your lungs into the victim’s lungs so they can absorb oxygen. This assumes that there is adequate oxygen in your exhaled air.
Air contains approximately 20% oxygen at sea level, 16% at 5000 feet elevation, and 13% at 10000 feet. When we breathe in air, our lungs absorb about 25% of whatever is available. So, at sea level, we exhale air with about 15% oxygen which is more than exists at 5000 feet and is adequate.
When you breathe into a victim’s mouth and have their nose closed, the air is forced into their lungs and you can see the chest rise. You have successfully gotten some amount of oxygen into the system.
Chest Compressions You manually compress the heart by pressing down on the chest. When you let up on the chest, the heart expands. The hope is that by compressing and expanding the heart, the blood flows through it as designed. Unfortunately, you don’t have an easy way to tell if blood is flowing. You can’t feel for a pulse or see results. You just need to believe in your efforts.
When properly performed, CPR simulates from 20 to 40% of normal circulation. That is not enough to sustain life indefinitely, but will be sufficient to put off the start of cell death in the hope that revival tools arrive soon. You should not expect CPR to restart a heart and have the victim pop back to life like is shown on TV. Your job is to keep oxygenated blood flowing until life support services arrive.
In communities with a thorough CPR training program and fast access to ACLS through an efficient Emergency Medical Services program, CPR can be effective up to half the time. Other places where CPR training is not promoted or where little ACLS support is available, the results are much less. Remember, your goal of administering CPR is to buy a little time for an emergency rescue team to arrive and revive.
So, what does CPR stand for? It stands for saving a life.