Questions were about the basic airway care.
There are 4 categories of airway techniques that we need to master.
- Bag mask ventilation
- Extraglottic decice
- Endotracheal intubation
- Surgical airway
During the Advanced Resuscitation course (AUT), Dr. Ellis told us a couple of fundamental points that are applicable to all ATPs. His first slide for the airway lecture read:
“Airway & breathing is about oxygenation and ventilation.
NOT INTUBATION, A PROCEDURE OR A DEVICE.”
He also carried on stating when talking about RSI:
“RSI done badly is worse than basic airway care done well.”
“Advanced airway done badly can be harmful, and we need to fully understand these fundamental concepts before going any further learning about various techniques.”
I’ve seen some pretty average BVM ventilation done on the road.
Let’s first become a master of BVM ventilation!
Bag mask ventilation (BMV)
*BMV often called BVM vent – Bag Valve Mask ventilation just to be confusing…
Difficult BVM vent predictors = MOANS
M = Mask seal such as beard
O = Obstruction / Obesity
A = Age > 55 due to muscular tone reduction
N = No teeth (keep the dentures in for BVM but take it out for advanced airway)
S = Stiff / snores (poor compliance meaning still lungs)
There is a great video titled “The difficult airway” explaining the difficult airway predictors by the developer of the concept so check it out.
Difficult airway predictors used here and much of airway techniques St John/AUT teach are defined by physicians in the U.S., and their book “Manual of Emergency Airway Mangement“.
Sniffing position (aka HELP = Head Elevated Laryngoscopy Positioning) used to be taught as a part of laryngoscopy. Dr. Ellis would like to see this as a part of basic airway technique. While C-spine protection still limits us using only jaw thrust, other patients may be placed on the sniffing position which can be achieved by aligning patient’s tragus of the ear to the sternal notch.
This concept works for all ages. We were taught to put towels under shoulders instead of head for kids bla bla bla…in the past but now you simply need to remember to do whatever to align: “Ear to sternal notch”
* Blair C sent me a great link for the airway anatomy and positioning (thanks Blair!)
The use of stretcher and lifting the head up may also help, and lifting head up 15~30 degrees also help reducing desaturation in case of apnoea.
Two hands technique
As we now have fire guys co-responding often, you may have luxury of having two people establishing and maintaining airway. Two hands technique is far superior in creating better seal, and in fact it should be the default technique and used whenever you can.
Traditional CE technique is found to be difficult skill even for anaesthetists and “Two thumbs down technique” should be used whenever possible. Check out the great presentation by Reuben Strayer below.
Also, worth checking out the reflection on this presentation by Scott Weingart (EMCrit).
Don’t push down!
I’m sure you’ve been taught to pull patient’s chin up into the mask rather than push the mask down to patient’s face.
Always use OPA/NPA
Pulling chin up to the mask will close patient’s mouth so you want to put one two or three adjuncts in.
Proper jaw thrust is done by:
- Open mouth wide
- Open mandible then displace it anteriorly out of TMJ (jaw joint)
- Place OPA as a bite block to maintain the position while lower teeth sits in front of the upper teeth
Squeeze small and slow!!!
Normal respiration is done by “negative pressure ventilation”, as negative pressure created by chest sucking air in rather than BVM pushing air in = “positive pressure ventilation (PPV)”. Pushing too much air too quickly can lead to badness pretty quickly!
It doesn’t take much to cause stomach insufflation that result in vomit and aspiration.
Hyperventilation is also one of the major killers of critically ill patients.
Please discuss various badness caused by PPV + Hyperventilation on coronary perfusion, intracranial pressure etc.
JAWS is a mnemonic for BVM technique some of you may like.
LIFL Bag-Valve-Mask (BVM) Ventilation
- Jaw thrust or sniffing position
- Airways (oral/nasal)
- Work together = 2 hands technique?
- Slow, small squeeze — 6-7 cc/kg, over 1-2 seconds, at <12/min, using low pressure.
Normal adult Vt (Tidal Volume) is around 500~600ml (1/3 of adult BVM) and some even advocate paramedics carrying only kid’s bag mask which is 500ml.
Optimal Bag Mask Valve Ventilation by Yen Chow also gives another good summary, so check it out!
Let’s do the basic airway & ventilation well!
Please please share your pearls with us!!!
Love to your family and bye for now 🙂