Bag Valve Mask (BVM) vs. CPR Mask - What's the Difference?
Have you been wondering about the differences between a bag-valve mask (BVM) and a CPR mask? Maybe you're on the fence about which you should carry first.
Both the BVM and the CPR mask will help someone breathe who can no longer take adequate breaths independently. However, there are times when one of these tools will be more appropriate than the other.
Neither the BVM nor pocket mask is necessarily better than the other; however, to be an effective care provider, you must understand the advantages and limitations of both these tools.
When it comes to rescue-breathing, little things can make a big difference.
What's the Difference Between a BVM and a CPR Mask?
Before we jump into the nitty-gritty, let's start with a rapid-fire list of differences between a BVM and a CPR mask.
Things to know about the BVM and CPR mask:
- The CPR mask has several names, including pocket mask, pocket resuscitator, and rescue mask - all these names refer to the same product.
- The BVM is also known as an Ambu-bag, or Manual Pulmonary Resuscitator (MPR)
- CPR masks require the rescuer to use their own breath to ventilate (breathe for) the patient
- BVMs require the rescuer to squeeze a bag to ventilate the patient
- CPR masks require entry-level training for use
- The BVM requires slightly more training than the pocket mask.
Now, let's explore each of these tools more carefully.
What is a Bag Valve Mask (BVM)?
A BVM or bag-valve mask is a medical tool designed to provide rescue breathing.
Before we talk about the best times to use a BVM, we need to understand the tool's major components.
Parts of the BVM:
- Bag: The bag is squeezed to push air into the patient's lungs (ventilation). Most BVMs are self-inflating, meaning the bag bounces back to form after it's compressed.
- Valve: BVMs have two main valves, one between the bag and the mask and one between the bag and the oxygen reservoir. The valves ensure that when someone squeezes the bag, oxygenated air flows into the patient's lungs.
- Mask: The Mask of the BVM is similar to the CPR mask. In fact, the two masks are often interchangeable. The mask seals around the patient's mouth and nose, preventing air leaks when you squeeze the bag. Masks are usually translucent, allowing you to monitor the mouth for vomit or blood.
- Oxygen Reservoir: The oxygen reservoir hangs off the end of the bag. The reservoir is a thin plastic bag that holds oxygen waiting to be delivered to the patient. Most BVMs have a port that allow rescuers to connect high-flow oxygen, which also fills the reservoir. (Note: the BVM will still work without the reservoir, it just won't deliver as much oxygen)
There are also different types of BVMs:
- The standard BVM is similar across multiple manufacturers, sharing all the parts we listed above.
- The pocket BVM shares all the same components as the standard BVM, but it can fold down to an easily packable size.
Now, let's talk about the CPR mask.
What is a CPR Mask?
Rescuers use a CPR mask to deliver rescue breaths to someone who is not breathing or who is breathing inadequately.
Let's talk about the different components of a CPR mask:
- Mask - The mask is applied over the patient's nose and mouth. The mask is usually built with a clear material so that the rescuer can monitor the patient's airway for vomit.
- One-way valve - The one-way valve lets you push air into the lungs but prevents harmful particles from entering your mouth.
- O2 Inlet - Some masks have an O2 inlet, and some do not. The oxygen inlet allows rescuers to attach an oxygen hose, giving the patient a higher oxygen concentration.
There are two main types of CPR mask:
- The CPR mask is the standard pocket mask with a one-way valve, as described above.
- The CPR shield is simply a plastic barrier that you can apply over the patient's face. Basically, the CPR shield offers some protection while performing mouth-to-mouth ventilation.
Now, let's discuss when to use these tools.
When Should I Use a BVM or CPR Mask?
Rescue breathing is a lifesaving skill. However, rescuers must understand when to perform rescue breaths before learning how to use a BVM or CPR mask.
Disclaimer: You should always receive proper training and authorization before using a BVM or CPR mask. Misuse of this equipment can easily cause harm. If possible, take a local EMT or MFR class.
Here are several times someone may require rescue breathing:
- Anytime a patient is breathing inadequately
- Drug overdose
- Head injury
- In conjunction with CPR
Rescue breathing is there to help someone who can no longer breathe themselves, regardless of the cause.
When Should I Use a CPR Mask instead of a Bag Valve Mask (BVM)?
The list below seeks to bring up some of the inherent advantages of using a CPR Mask.
Here are some advantages to a CPR mask:
- Less likely to over ventilate: Since the CPR mask requires you to literally breathe for the patient, it's much easier to feel when their lungs have become full. With a BVM, it's easy to accidentally give too much air.
- Easier to get a good mask seal: This is especially true when you don't have help. The BVM only gives you one hand to hold the mask. Alternatively, you can hold the CPR mask with both hands.
- More portable: The CPR mask is much easier to store in a pocket, glove box, or backpack, and CPR masks are less expensive to replace.
- Less training required: CPR masks require less training to use than a BVM. However, CPR masks can still cause harm to a patient if used incorrectly. Get trained!
Now, let's discuss the advantages of the BVM.
Reasons to Use a BVM Instead of a CPR Mask
Below, we list several advantages the BVM has over the CPR pocket mask.
Here are some reasons to choose a BVM:
- To deliver more oxygen: Without any extra oxygen, CPR masks deliver about 16% O2 (exhaled air). On the other hand, BVMs can deliver 21% (room air). Also, it's easier to attach supplemental O2 to a BVM, raising the O2 concentration even more.
- Less fatigue: Some people, especially those with breathing problems themselves, could find it fatiguing to breathe for someone with a CPR mask. Alternatively, BVMs are operated with your hands, so you can easily switch sides when one hand becomes tired.
- Lower risk of contamination: BVMs don't require the rescuers face to be anywhere near the patient's mouth, further reducing the risk of contamination.
Now, let's learn how to use these tools.
How to Perform Rescue Breathing with a BVM or CPR Mask
Learning to help someone breathe is truly a rewarding endeavor. Paramedics see countless lives touched by rescuers who wield this skill with finesse.
Unfortunately, the opposite is also true - many well-intentioned first responders believe rescue breathing is a simple task with little that can go wrong. As a result of this thinking, they inadvertently cause harm.
Note: The guide below is just a general reference and NOT a substitute for live practice with trained instructors.
Steps to using a BVM:
- Safety: Always protect yourself and protect the patient. Wear gloves, mask, and eye protection if possible. Also, if you are in an unsafe environment (fire, flooding, etc.), consider moving yourself and the patient before rendering care.
- Equipment: Have all your equipment checked and ready; this means your BVM, your OPAs and NPAs, a suction device, and a full portable O2 tank.
- Check breathing and pulse: Look, listen, and feel for breathing and a pulse. If the patient doesn't have a pulse, call 911 (place phone on speaker) while you begin hands-only CPR. If the patient has a pulse but isn't breathing, it's time for rescue breaths.
- Position the patient: The "sniffing position" is the best position to open the airway. To achieve the sniffing position, consider padding under the patient's head (for adults) or shoulders (for children). You can also perform the jaw-thrust or head-tilt chin-lift, which pulls the tongue forward.
- Place the mask: Place the mask carefully, trying to ensure you have the best seal around the mouth and nose. For a BVM, grip the mask with the thumb and pointer finger, grip the patient's jaw with the remaining middle, ring, and little finger - this is called the "C-E" grip. For a CPR mask, use one hand to hold the mask on the chin and one hand to grip the mask above the nose.
- Breathe for the patient: Carefully squeeze the bag for a BVM or blow into the mouthpiece of a CPR mask. Provide just enough air to see the chest rise. Overventilating will push air into the stomach and impede blood from returning to the heart! Give adults a breath about every 6 seconds, children will need a breath about every 3-5 seconds, and newborns will need a breath about every 1-1.5 seconds.
- Use adjuncts if needed: Always have your NPA and OPA ready. These tools prevent the tongue from occluding the airway, helping air pass freely to the lungs.
These are the basic steps. To better understand these concepts, here's a video on how to use a BVM.
Also, here's a video on how to perform rescue breaths.
CPR masks and BVMs are both great tools when used correctly. Each has its pros and cons. The important thing is to learn how to operate these devices so you're prepared to use them in a real-world scenario.
Every country, state, and county has its own set of protocols surrounding how providers perform CPR and rescue breathing. Be sure to research and follow local guidelines.
If you can, contact your local fire department or ambulance service and ask about first responder classes. There's nothing like hands-on experience.