17 replies to this topic

[MikeEMT]

So can someone explain to me the differences between the blind insertion airways (i.e. combitube, King) and an actual endotracheal tube?

As a basic we can do the combitube but obviously can't intubate. I have heard that combitubes are not to be used for long term airway support.

Looking at them they look pretty much identical to me (other than the fact that combitubes are dual lumen).

I know there has to be some differences in functionality otherwise intubation would be a basic skill. So what exactly makes an ET tube different from a combitube?

Elementary question, but one that I have been curious about.

[Curiosity]

We don't use combitubes here anymore. We have kings now. One difference is, blind insertion vs visualized insertion.

Blind slips in without the need to see the anatomy and sits on top of the vocal cords. It directs the air flow towards the trachea, reducing gastric insuflation. They don't however provide a definitive airway. There's a risk of aspiration if the patient vomits because the vomiting may not be visible because of the tube blocks the view.

Intubation requires the anatomy to be seen and a tube passed through the vocal cords. There's more to it than just push a tube in. Landmarks, techniques, troubleshooting difficult airways. This tube completely isolates the trachea therefor in case of vomiting, the risk of aspiration is minimal.

They both have pros and cons, kings are faster and much simpler to insert but don't offer the long term protection of intubation. I find monitoring with a et tube easier than a king lt. Greater risk of damaging the anatomy with an et tube (improper techniques). Et tubes also require a lot of practice and is a skill one needs to maintain in order to be proficient.

[Resqmedic]

Intubation is still the gold standard for securing an airway, blind insertion airways have been gaining popularity, and every year I hear that paramedics will no longer perform ETs, But I still see all the air medical services(around here anyway) using only ET tubes, as well as in the ER's. Feel free to correct me if I am wrong, and I would like to know of services that no longer use ETs as well!

[island emt]

As said above the endotracheal tube is the gold standard for secure a definitive airway. After inserting an inflatable ballon cuff is filled which occludes the area around the tube making aspiration all but impossible. the combitube or king or any of the other blind insertion airways are just a set of tubes that are introduced into the oropharynx in the hope that one will hit the trachea and one the esophagus. The LMA is along the same lines, it looks like a part of the female anatomy that is placed in the anterior throat in an attempt to control airway. It won't stop aspiration or stay put when bouncing down the road.
Plus the multi tube adjuncts are way more expensive to purchase and have the same short expiration dates as ET tubes, which cost about $3.35 ea instead of $50.00 like the combitubes , or $38.00 for the king.

[paramedicmike]

I know there has to be some differences in functionality otherwise intubation would be a basic skill. So what exactly makes an ET tube different from a combitube?

I don't have a lot of time to get into detail here. But don't fool yourself thinking that it is simply functionality separating a skill between paramedics and EMTs.

I'll expand later when I have a little more time.

[MikeEMT]

I don't have a lot of time to get into detail here. But don't fool yourself thinking that it is simply functionality separating a skill between paramedics and EMTs.

I'll expand later when I have a little more time.

I am assuming there is more to it than what I know which is why I asked. The other day I transported a patient that had been tubed. This was an airlift patient and was on a ventilator. I didn't have time to ask the RN's (transport was less than 3/10 of a mile).

When I did my clinical at harborview, i was given the opportunity to watch an intubation but missed it due to another patient coming into the ER.

I enjoy learning and am never content with just the minimum skills. If I can develop a basic understanding of some of the stuff outside my scope of practice maybe it will help me in the field. Example here is the advanced airway. We don't drop the tubes as Basics but we do ventilate the patient once the tubes are in place.

Thanks for the replies so far. Very helpful.

[paramedicmike]

So can someone explain to me the differences between the blind insertion airways (i.e. combitube, King) and an actual endotracheal tube?

One of the biggest differences is that a blind insertion tube is just that. It is blindly inserted. You don't have to look. You don't have to see. You just open the mouth and put it in. The tube itself does not directly enter the trachea. Rather, it sits supraglottically and air is directed through the tube, through the vocal cords and into the trachea/lungs that way.

Endotracheal tubes, under most conditions, require direct visualization of the glottic opening in order to properly place the tube. The tube is placed directly into the trachea and air is pushed directly through the tube into the trachea and then the lungs.

There is one exception to this rule. Nasally intubating a patient does not require direct visualization. It does, however, require that the patient be breathing.

As a basic we can do the combitube but obviously can't intubate. I have heard that combitubes are not to be used for long term airway support.

This is correct.

Looking at them they look pretty much identical to me (other than the fact that combitubes are dual lumen).

A passing, superficial glance will make them look remarkably similar. Closer inspection, however, will reveal several major differences.

As you noted Combitubes are dual lumen. They are much larger than ET tubes. In most cases a Combitube is not going to fit into the glottic opening. You'll also note the two separate balloons. Looking at an image of proper Combitube placement will tell you why the balloons are where they are and the function they serve.

ET tubes are smaller than the Combitube because they go directly into the trachea. Only one balloon is needed to prevent backflow of ventilated air.

I know there has to be some differences in functionality otherwise intubation would be a basic skill. So what exactly makes an ET tube different from a combitube?

A blind insertion airway cannot adequately secure an airway. It cannot prevent aspiration. It cannot prevent foreign bodies. It can provide short term ventilatory assistance by way of directing air into the trachea/lungs to assist with ventilation and, with any luck, respiration. An ET tube can secure an airway. It can prevent aspiration. It can direct air directly into the lungs so that every squeeze of the bag ventilates, and with any luck assists with respirations of, the patient.

Intubation is not a basic skill for many reasons not the least of which is the completely inadequate education involved in preparing an EMT to work on an ambulance. This is to say nothing of the increasing number of studies questioning the effectiveness of paramedic placement of ET tubes.

Elementary question, but one that I have been curious about.

Hope this helps even more.

[chbare]

I would not consider an endo-tracheal tube a "gold standard." Intubation carries it's own risks and complications. Also, intubation does not prevent aspiration. In fact VAP is a major problem and frequent oral care along with frequent oral suctioning and secretion management are often interventions included in VAP bundles.

[BAYAMedic]

The risks and complications are noted but that doesn't mean its not the gold standard. As artificial airways go, I challenge you to list an airway that adequately prevents aspiration, prevents gastric insufflation, and can be used long term, while not being so invasive to need to be surgically placed. Every artificial airway on the market must prove itself in relation to the ETT. The Gold standard of which all others must be compared.

BAYAMedic

[chbare]

What about a trach? Would an ET tube be the best choice if independent lung ventilation is needed? Unfortunately, it's not as simple as making the generalisation that the ETT is a gold standard.