|
Authorized Provider of Canadian Red Cross First Aid and CPR courses in Toronto
Click here to return to the main page
Every 15 seconds someone is injured and requires medical attention...you've got to be prepared.
You would expect a first aid course to make you more aware of potential dangers. But did you know your participation may reduce your risk of injury by up to 40%?
--------------------------------------------------------------------------
How CPR
Works
by Ann Meeker-O'Connell (How Stuff Works)
PLEASE NOTE: This article is not intended to be used as a method for teaching CPR. For proper CPR training, consult your local Canadian Red Cross location for available classes. Vital CPR - First Aid Training is an Authorized Provider of the Canadian Red Cross, and is based in Toronto, ON. We offer both public, and private group classes in the Greater Toronto Area. Our goal is to provide first aid and CPR training to every person in Toronto.
You're playing your usual weekend pick-up basketball game with friends. Without warning, one of your team mates suddenly crumples to the ground. You scream out his name, but there's no response. His face turns pale and bluish, and you can't see his chest rise and fall to breathe. You listen for a heartbeat, but you can't find a pulse at all. You quickly grab your cell phone and dial 911.
Every year, this type of scenario is played out more than 600 times a day in the United States alone. Without rapid medical intervention, the prognosis is grim. Sudden cardiopulmonary arrest is the leading cause of death for all adults, male or female.
Fortunately, modern medicine has come up with a number of tools to combat cardiopulmonary arrest. Many of these emergency procedures require medical training and/or complex equipment, but one, cardiopulmonary resuscitation (CPR), can be used in the field by lay people with only a little bit of training. In this edition of How Stuff Works, we'll explore how this simple first aid technique can help save lives.
Cardiopulmonary Arrest
Cardiopulmonary arrest simply means that your
heart (cardio) and lungs (pulmonary) aren't
working -- your heart isn't beating, and you
aren't breathing. Many different things can lead
to cardiopulmonary arrest, including:
Stroke
Drug overdose
Heart attack
Near drowning
Choking
Blood loss
Electric shocks
Carbon monoxide poisoning
A heart
attack, for example, can damage the heart muscle
and impede its ability to vigorously contract,
resulting in cardiopulmonary arrest. If you've
read How Your Heart Works, you know that the heart
is a muscle that expands and contracts under the
electrical control of a special group of
pace-making cells. The pumping action of the heart
pushes blood teeming with oxygen and other
nutrients out to the rest of your body. If your
heart isn't beating properly or at all, blood
isn't supplied to your body, and oxygen and other
vital nutrients don't get delivered to your
tissues and organs (including your heart). With no
energy to power your body, vital organs like your
heart and lungs stop working, and you are in a
state of cardiopulmonary arrest.
In a heart attack, something like a blood clot
obstructs one of your coronary arteries and cuts
off blood flow to your heart.
Cardiopulmonary arrest is an extremely dangerous
situation. Within 4 to 6 minutes without oxygen,
your brain cells begin to die off rapidly. With
each additional minute, the damage builds up. Most
people cannot survive long in such a state.
CPR Basics
Cardiopulmonary resuscitation (CPR) is a first-aid technique used to keep victims of cardiopulmonary arrest alive and to prevent brain damage while more advanced medical help is on the way. CPR has two goals:
keep
blood flowing throughout the body
keep air flowing in and out of the lungs
While the modern emergency room has high-tech equipment and an arsenal of drugs to help treat victims of cardiopulmonary arrest, CPR is a simple technique that requires little or no equipment. What you do is pretty basic:
Blow forcefully into the victim's mouth to push
oxygenated air into the lungs. This allows oxygen
to diffuse through the lining of the lungs into
the bloodstream.
Compress the victim's chest to artificially
re-create blood circulation.
CPR must be performed in a specific, timed
sequence to accurately mimic your body's natural
breathing pattern and the way your heart pumps.
When someone collapses right in front of you, your
first reaction is often sheer terror. But while
you're panicked and unable to act, valuable
minutes are slipping away. To counter this, many
organizations such as the Canadian Red Cross offer
classes that train you in CPR and basic first aid
and give you hands-on practice to hone your CPR
skills. Then, if you are confronted with an
emergency situation, you are prepared to jump into
action.
CPR
Step-by-Step
Cardiopulmonary arrest means that both heart and
lungs have stopped working properly, so it would
make sense to check and see whether a victim is
breathing and whether or not their heart is
beating. However, current CPR guidelines don't
require a layperson to check the victim's pulse
before starting CPR. Why is this?
The answer is that the average person has a lot of
trouble finding and determining pulse accurately.
Think about how difficult it can be to find your
own pulse, and then imagine trying to repeat the
process on an unresponsive person. If someone is
not breathing, their heart is already in danger of
quitting (if it hasn't already) due to lack of
oxygen. Since the first steps in CPR address the
victim's respiratory state, you can try and get
them breathing again right away. Then, you can
check for a pulse. Skipping an initial pulse check
simplifies CPR and saves valuable time; every
minute that you delay starting CPR reduces the
odds that the victim will survive by 7-10 percent.
What should you do to help a seemingly unconscious victim? The first thing you'll want to do is to figure out whether or not the victim is really unconscious. Just like you were trying to get them out of bed, you should call out to them, tap them, and gently shake them to try and provoke a response. You also should check to see if they are breathing. If you try and perform CPR on someone who is not in cardiopulmonary arrest, you can actually hurt them!
If you can't rouse them, the very next thing to do is have someone call 911 so that professional paramedics will be on their way to the scene while you are performing CPR. This is very important, because, with the exception of choking, CPR doesn't address the underlying causes of cardiopulmonary arrest. It is only meant to buy time until the victim can get intensive medical care.
After you've called for medical assistance, you need to begin CPR. In order for CPR to work, the victim must be lying on his or her back on a flat surface. If the victim is face-down, gently roll the person toward you while making sure that you support their neck. Once the person is on their back, you can then use the "ABCs of CPR" to guide you through the rest of process:
1. Airway:
clear obstructed airways
2. Breathing: perform mouth-to-mouth breathing
3. Circulation: start chest compressions
We'll talk about each of these steps in detail in
the following section.
The ABCs
Here's a summary of how you might perform CPR on a non-responsive adult (There is actually a different procedure used to save infants and young children). To learn all about and practice CPR in detail, you should sign up for training from an organization like the Canadian Red Cross.
A is for Airway
When you pass out, your tongue relaxes, and it can roll back in your mouth and block your windpipe. Before you can start CPR on an unconscious person, you'll probably need move their tongue out of the way. Here's how to clear a blocked airway:
1. Place
the palm of your hand across the victim's forehead
and push down gently.
2. With the other hand, slowly lift the chin
forward and slightly up.
3. Move the chin up until the teeth are almost
together, but the mouth is still slightly open.
Tilting the head back and lifting the chin move the tongue out of the airway. At this point, you should check again for breathing. If the victim is choking on something, you may see their chest heave as they try to breathe, but you won't be able to feel or hear air being exhaled. You'll have to take additional measures to clear out what's blocking their windpipe, including:
1.
Compressing the abdomen with forceful thrusts.
This creates pressure that forces the object up
and out of the windpipe.
2. Trying to manually dislodge the object with
your fingers.
Once this is done, you have to check for signs of
breathing again. Just clearing out the windpipe
may sometimes be enough to allow the victim to
start breathing on their own! If the victim starts
breathing and moving around on their own, you can
stop CPR. If this doesn't happen, you'll have to
help them breath, by providing mouth-to-mouth
resuscitation.
B is for Breathing
Your lungs
have one main function: remove carbon dioxide and
take up oxygen. Normally, the muscles in your
chest contract and expand your chest cavity,
allowing your lungs to fill up with air. Oxygen
and carbon dioxide diffuse across the immense
surface area of your lungs. Finally, your chest
muscles relax, and you exhale.
Rescue breathing uses your lungs to force air into
the victim's lungs at regular intervals. The
timing of each breath (about 1.5 to 2 seconds per
breath) mimics normal breathing. However, the
process is much more like blowing up a balloon
than real breathing. You inhale deeply, form a
tight seal with your mouth over their mouth, and
exhale strongly to push air out of your mouth into
theirs. Because you also pinch the victim's
nostrils closed, the air has nowhere to go except
down into the lungs, which expand as they fill
with air.
Mouth-to-mouth breathing is hard work. Normally,
when you inhale, the chest muscles drive the
process. In artificial respiration, you're working
against the victim's relaxed chest muscles. When
the chest muscles are relaxed, the chest cavity is
small, keeping the lungs in a deflated state. As a
rescuer, you have to exhale forcefully into the
victim's mouth for 1 to 2 seconds to overcome this
resistance. As the lungs fill with air, the
victim's chest is pushed up at the same time; you
can actually see it rise. When you remove your
mouth from the victim's and break the air seal,
their chest falls and once again deflates the
lungs. As in normal breathing, this results in air
being exhaled from the victim's mouth.
Does air exhaled from someone else's mouth really provide enough oxygen to save an unconscious person? Normally, the air you inhale contains about 20 percent oxygen by volume, and your lungs remove about 5 percent of the oxygen in each breath. The air you blow into a victim's mouth thus contains about 15 to 16 percent oxygen, which is more than enough to supply their needs.
After you've given the victim two breaths, you then check to see whether or not they have a pulse and whether they are able to breathe on their own. This will determine what you do next.
If the victim . . . you should...
Is
breathing and has a pulse... stop CPR, and stay
with them until help arrives.
Is not breathing and has a pulse... continue
rescue breathing.
Has no pulse... begin chest compressions,
alternating with rescue breathing.
C is for Circulation
If the victim's heart is not beating, all your breathing efforts are for naught; the oxygen that you're getting into their circulation isn't going anywhere! Once again, you have to take over for a failing organ. This time you essentially become a surrogate heart to pump oxygenated blood out to the rest of your body. How can you have any effect on blood flow from outside of the body? All it takes is your hands and some strength. The steps are simple:
1. Kneeling
by the victim, place the heel of your hands one
atop the other about .4 to .8 inches (1 to 2 cm)
from tip of the breastbone.
2. Using the weight of your body, push the
victim's chest down. You should compress their
chest 1 to 2 inches (2.54 to 5.08 cm).
3. Hold in this position for half a second, then
relax for half a second
4. Repeat steps two and three 14 more times.
5. Give the victim two rescue breaths as you did
before to deliver more oxygen to the blood.
6. Repeat steps 1 through 5 three more times, then
check for a pulse.
In reality, all you are doing is squeezing the
heart between the breastbone and the backbone to
force blood out. Compressing the chest creates
positive pressure inside the chest that pushes
oxygenated blood out of the heart through the
aorta. From here, it travels to the brain and then
on to other parts of the body, delivering oxygen
for cellular respiration. When you relax, the
pressure inside the victim's chest subsides.
Deoxygenated blood moves back into the heart from
the veins.
As the chest is compressed, positive pressure is
created inside the chest, and oxygenated blood is
pushed through the arteries to the brain and other
organs. When you release, the pressure drops, and
blood flows back into the heart from the veins.
CPR's Role in Rescue
CPR extends
the window of opportunity to perform more
elaborate first aid procedures. By itself, CPR
cannot save the majority of victims of
cardiopulmonary arrest. CPR only temporarily
restores circulation to only 10 to 30 percent of
what it would be with a healthy heart. Further, in
about two-thirds of people in cardiopulmonary
arrest, the heart goes into what's known as
ventricular fibrillation. In this state, the heart
muscle quivers rapidly, like a bowl of Jell-O, and
is unable to beat properly. CPR cannot stop
ventricular fibrillation, and only about 4 percent
of patients who receive CPR alone will survive an
attack.
In order to restore a normal heartbeat, an
electrical shock must be delivered to the heart.
This is called defibrillation. The shock itself
doesn't switch the heart back on - it's not like
flipping a tripped circuit breaker. Instead,
defibrillation actually stops the heart briefly!
This gives the pacemaking cells a chance to
re-establish a normal heartbeat.
So why do CPR at all if it can't address the root causes of cardiopulmonary arrest? The bottom line is that CPR is an important part of a comprehensive response to a cardiac emergency. Defibrillation requires special equipment that has to be brought to the patient, and CPR can keep a patient alive until a defibrillator arrives. When CPR is started within 4 minutes and defibrillation within 10 minutes of an attack, the survival rate skyrockets to 43 percent. Other factors that contribute to survival are:
Rapid access to emergency care from paramedics and
other medical professionals.
Quick provision of other supportive medical
care, such as epinephrine, a drug that stimulates
the heart.
CPR and Infectious Disease
It's clear that CPR is an effective part of the emergency response to cardiopulmonary arrest, one that could potentially save thousands of lives a year. Yet, in most cases, victims aren't getting this lifesaving treatment, even when bystanders are familiar with CPR.
Why won't people perform CPR on strangers? It turns out that a large number of people are afraid of contracting some nasty disease during mouth-to-mouth resuscitation. This fear was heightened by the emergence of deadly infectious diseases, such as HIV, that are spread by bodily fluids. Even though there have been no documented cases of anyone ever catching AIDS during CPR, there is still a chance, however tiny, of this happening.
To assuage
the public's fear, CPR training now incorporates
personal protective gear during the various steps.
Some of the safety devices used include:
Gloves - to prevent contact with saliva if you
have to reach in their mouth or blood if the
victim has cuts or abrasions
Personal resuscitation masks - allows you to
provide artificial respiration through a barrier
that prevents contact with saliva and mucus
membranes
The one drawback is that you have to carry your
CPR kit with you everywhere. Most people don't
plan when they go into cardiopulmonary arrest, so
you never know where you might need your gear.
-------------------------------------------------------------------------
First Aid Skills for Everyone
Learn lifesaving skills in just hours! Whether you are a professional rescuer, teacher, office worker, or student, Vital CPR - First Aid Training has the right course for you. Set in a fun, interactive environment, we offer courses for people of all ages, skills and interest levels.
Free CPR Workshop and other community offers. Click here to get more information about our free CPR workshops, student discounts, and other special offers for non-profit groups in the Toronto area.
Is this your first time visiting our website? Do you need help registering? View our Frequently Asked Questions.
Why train with Vital CPR? Click here to find out why we are your best choice for first aid and CPR training in the Greater Toronto Area.
©Copyright 2004
Vital CPR
- First Aid Training, Toronto ON Canada
All Rights Reserved
For more information feel free to Contact
Us