For this installment of my IFAK Essentials Series: The NPA & OPA, JIM (a career ER nurse) has offered his medical expertise to write an excellent article regarding an essential function every medic should know: how to protect a patient's airway. JIM wrote this article in it's entirety, so Kudos to him! I've tweaked the format slightly and added more information/links/pictures. Look for this installment of the IFAK Essentials Series to show up as a ZSS Feed Article soon.
In a survival situation, traumatic injuries will occur and on occasion, this means you will have to protect the patient's airway (or establish one in the first place) to ensure your patient's survival. Now that you understand the importance of understanding how to use these simple and inexpensive IFAK Essentials
, lets launch into the meat of the argument, the how/when/why their use.
This article will focus on two lifesaving implements, the N
and the O
. These instruments are used for the airway-management of a patient. If you know how to use one, they should belong in your P
orld (PAW) F
or trauma-bag and with a little training and this article, you can better equip yourself to save lives.
Below is a diagram of a normal, unobstructed airway. Try your best to memorize the basic functions of this airway as it's absolutely vital to protect this
or NPA prevents the tongue from falling back into the pharynx and blocking the airway. This could happen when the muscles in the mouth are relaxing:
^Now you could open the airway manually, using the 'Chinlift' and 'Jawthrust'- methods as demonstrated in the picture above, but of course you can't treat other injuries/people when you've gotta keep someone's airway open. This is where you use a NPA or OPA
for. Source for Chinlift and Jaw Thrust technique
First, let's take a look at the NPA:
^The NPA is important enough to be issued to most US military members thanks to their new Improved Individual First Aid Kit Source in PDF
The NPA is a piece of flexible tubing that is inserted into the Naso-pharynx:
This can secure the airway, because when a patient becomes unconscious, the muscles in the jaw relax and can allow the tongue to slide back and obstruct the airway resulting in suffocation and loss of the patient.
A NPA prevents this, though not as well as a OPA
which I'll cover later.. So this begs the question: When do I use a NPA and when not?
WHEN TO USE
The NPA is used on conscious people because there’s a smaller gag-reflex (which can cause vomiting) with a NPA than a OPA
. A NPA also has less tendency to fall out, so it is preferred when transporting a patient or in tactical-conditions. Also, at times you won't be able to place the OPA
due to potential alternative injuries to the patient (for example if the patient is suffering from lock-jaw)
WHEN NOT TO USE
- Suspected skull-base fractures (we don’t want to poke the NPA directly into the brain, now do we..)
- Severe facial trauma (like when you can’t find the nose anymore).
– Nose-bleed (because blood will get into the NPA, rendering it useless)
A thing that also could go wrong when inserting a NPA is that you hit the Vagus Nerve. This nerve regulates the parasymphatic-processes. IOW: It slows your body down. When this nerve is triggered, people can get a very slow heartbeat, become dizzy and could faint for a couple of seconds. This is called a vasovagal syncopy and it will go away on itself.
Hold it buster, before we try to jam a NPA into someone’s nose, we need to choose the right size NPA. Measurement of a NPA is done in ‘French’ (F), which is also called a ‘Charrière’ (Ch). 1 F/Ch is 0.3mm. Sometimes their also called 6-0 or 7-0, which stands for a thickness of 6 or 7mm. NPA’s can range from 20F to 36F.
^The average NPA-size for a adult is 28F, however you should make sure that you’ve got the right size before inserting them, and here’s how you do that. There are 2 methods. The first one is that you hold the NPA on the cheek of the victim. The NPA should reach from the tip of the chin till the earlobe.
^Second way is from the tip of the nose till the earlobe. If the NPA's length looks like this, you're good to go.
A NPA usually comes with a small sachet of lubricating-gel. This is put on the NPA to make the insertion easier. Sometimes you can also use spit. Don't be squeamish, this is your patient's life on the line, set aside your queasiness.
Below is a pictorial representation how to insert a NPA (after you measured it): Orient the bevel end on the NPA so that it will pass along the inside of the nasal cavity with minimal effort and insert the NPA until the flange (the large end of the tube) is seated on the patient's nose.
WHERE TO BUY:
SPSERVICES (UK website)
LIFE MEDICAL SUPPLIERS
MED-WORLDWIDE (Global shipping)
Planet CNM, Educational Resource for the NPA
University of Virgina: Airway management tools
Youtube Video of proper NPA insertion by Army Medics
^Our own Doc Simon being intubating with an NPA while serving in Afghanistan.
The Oral Pharyngeal Airway is also called a ‘Mayo-tube’ , a ‘Guedel-airway’ or sometimes a ‘J-tube’. This sort of airway is used on unconscious people (which don’t have a gag-reflex anymore). They can be used with skull-base injuries and have a lesser chance of triggering a vagovagal syncope.
However, you’ve got to get the size just right because a wrongly inserted OPA
can block the airway even further or cause bleeding. A OPA
also takes a bit more thought to insert than a NPA.
They also have a number, indicating the length of the OPA
. For example, a size 1.0 OPA
, is 10cm long. A 0.9 OPA
is 9cm. long, etc. The problem it that there's also another size-system, which is shown in the above picture. Here, a red, 1.0 OPA
is referred to as a size 4. I've got no idea why..
HOW TO MEASURE THE OPA
This is how you measure the correct size OPA
on a victim:
You could also use this method:
Keep the mouth open by putting your thumb onto the bottom-teeth. Insert the OPA
as shown in the picture. When it’s about half-way in or when you feel the tip of the OPA
hitting the top of the oropharynx, turn the tube 180 degrees, so that the tip now points to the throat.
At this point, rotate the OPA
Here's a good video of the OPA
as used in operational medicine (may take a little while to load): WMV File, Right Click, Save As
WHERE TO BUY:
SPSERVICES (UK website)
LIFE MEDICAL SUPPLIER
Rn Web article outlining proper placement
Pictorial Demonstration of OPA use
Youtube Video showing OPA insertion
Youtube Showing how quick and easy OPA insertion is with a bit of practice
So that’s it. When you know the how, when and why of the NPA and OPA
airway devices. These two items are essential pieces of kit for any serious trauma medic and thanks to their ease of use, can and should be added to any trauma bag/kit you may have.
Thanks for reading, class dismissed.