This transcript has been edited for clarity.
Robert D. Glatter, MD: Hi. I'm Dr Robert Glatter, medical advisor for Medscape Emergency Medicine. I would like to welcome Dr Nina Shapiro, a professor and director of pediatric otolaryngology at the David Geffen School of Medicine at UCLA.
Today, we will talk about a recent case report in the British Medical Journal that really is important for all medical providers and all surgeons. It involved a patient with a tracheostomy who had a complication after being swabbed through the tracheostomy site. It turned out that the end of the nasal swab broke off and bronchoscopy was required in order to retrieve the foreign body.
Thankfully, the patient did well, but it reveals some important things we should discuss about when swabbing a patient with a tracheostomy.
Nina L. Shapiro, MD: Thanks for having me.
Glatter: It's my pleasure. I really want to discuss this case because it has such important implications. All of us see patients with tracheostomies or those who have had pharyngeal surgery, and it's so important to understand what the indications are and how to approach such patients.
Let's start by talking about current Centers for Disease Control and Prevention (CDC) and American Head and Neck Society guidelines regarding taking swabs in patients with tracheostomies.
Shapiro: The CDC guidelines are still recommending that the nasopharynx is the ideal location to swab for COVID-19. That is the area that contains the most viral load in a patient who's going to have the virus.
We also talk about the nasal swab, which is different from the nasopharyngeal swab. That's where you swab in the anterior part of the nose at the turbinate and you do that several times. Then some patients are even getting oral swabs.
The nasopharynx, which is directly in the back of the nose (not up), about 6 inches from the tip of the nose (it's a long distance) — that's the area that you need to get to for the best, most accurate culture.
Glatter: It's important to note the technique. Most people think you just put the swab in the nose and that's it. There's a technique and training involved in this. I think most hospitals now are doing this in order to ensure continuity and also for patient safety.
Shapiro: Yes, exactly. There was a case of an injury in the nose where a patient had a previously undiagnosed encephalocele after sinus surgery several decades prior. The swab actually poked into the encephalocele and the patient developed an acute cerebrospinal fluid leak from the swab. These are very rare complications, but as with any test, you need to understand that there are risks to it.
Glatter: In patients who've had prior anterior encephalocele surgery, the optimal approach would be to avoid this. Where would you suggest we swab? Do we use the saliva or oropharyngeal swab? What would be your approach?
Shapiro: If it's a fresh postop, usually we do an oropharyngeal swab. If it is a patient who's had prior surgery and they're healed, and if it's a trained tester, they should know. We always tell our residents that in general with sinus surgery, stay low and medial — that's the safe place to be. Anything up, you're going to potentially injure the sinuses or worse. Anything lateral, you can also cause some damage. Low and medial is a safe place to go even after sinus surgery.
Glatter: Wearing the proper personal protective equipment (PPE) is really one of the most important things of doing this. What would you suggest would be the appropriate attire in order to do the swab?
Shapiro: Many of these COVID testing places are drive-throughs, and the staff are wearing full PPE. For COVID sampling, they wear N95 masks, sometimes a second mask over that, a face shield, and eye protection. If it's a high-suspicion COVID patient, then oftentimes they'll wear a powered air-purifying respirator (PAPR) as well.
Glatter: That's key, because the PPE aspect of this is really one of the pitfalls. What we see is that in people who end up testing positive later on, the PPE wasn't properly donned or doffed while doing the procedure.
Shapiro: That brings up the point about a patient who has an indwelling tracheotomy tube that they need to cover. In general, they need to have a covering over their trach and a covering over their face to protect others and to protect themselves. They don't only need a covering over the trach because there's oftentimes some viral contamination in their face as well.
Glatter: Exactly. I'm going to get into the actual sampling of the site. I know you brought some models with you. Please show us the proper approach and then maybe discuss the heat and moisture exchanger (HME) filter aspect, the cannula, and sampling processes.
Shapiro: I brought an example. This is a pretty standard adult tracheotomy tube. It's a size 6, which is pretty standard for a medium-sized or small adult. The cuff you can see right here, and this is what would be blown up if a patient were on a ventilator.
An adult trach has two parts to it. This is the trachea that touches the tracheal airway, and then there is the inner cannula. This is what is removed when you're cleaning a trach to not have to remove the whole tracheotomy tube. You can actually remove the inner cannula and culture the inner cannula.
This would be the culture swab right here. There's this little line right there — that's the natural break point — and you can actually put it out of the patient's airway.
If this is broken off, you're not in the patient's airway. You can actually culture the inner cannula to get sample, clean it, and then put it back into the patient without having to touch their airway or remove the whole tracheotomy tube at the same time.
If you put it into the patient, you see how far it has to go. Here's the tip, and to get it into the actual trachea, it's a fair distance. Even then, if you're not touching the tracheal wall and you're just sort of in the airway itself, you're not going to get a sample. And then you can see that it can get stuck, and that's a problem.
Glatter: What do you do when you get stuck? That's an important question, right?
Shapiro: Yes. If it gets stuck, what you can do is actually remove the inner cannula, and that may remove the whole thing a little more safely. As an airway surgeon, I don't like to do things blind in the airway. We're used to having our scopes and doing things under direct visualization. We like to see what we're doing, for obvious reasons. Even people who are doing suctioning trachs, we've had emergency cases where the suction catheter has sheared off into the airway, and that becomes an emergency foreign body.
If you did a COVID test on a patient and the swab fell into the airway, you don't know whether they're COVID positive or negative. All of a sudden, you're doing an aerosolizing procedure on a COVID unknown. Not only is it an emergency, it is a potentially COVID-positive patient. You're stuck two ways when that happens.
Glatter: That actually brings me to another point. There are some recent studies looking at aerosol-generating procedures and intubation not being as risky as we thought it was in patients who are positive for COVID. They did some studies looking at aerosols, aerosolization, and particles and droplets.
It wasn't as risky as we would expect, which is interesting because all of us are fearful of this issue. We had intubation boxes in the early days of COVID hoping they would actually protect us, but it turns out they weren't really protecting us. As the studies evolve, we learn more and more.
Do you have any pearls you'd like to give us — the big takeaways from this whole medical misadventure case?
Shapiro: One thing to consider is that even though a patient has a trach, you can still culture the nasopharynx and you can do that very safely and get an adequate sample — and in some ways a more adequate sample. I think this case in BMJ and the case about the spinal fluid leak provide a wake-up call for everybody to relearn their anatomy and understand where they're going — the angle of the airway in the trach, and the angle of the airway for the nasopharynx. I think that's really important.
It's important to get a little training. Obviously, a lot of the physicians are not doing the testing themselves. Make sure that whatever testing site you're using, they understand the implications of sampling an airway.
This also goes for patients who have had laryngectomies, because they may or may not have a trach. Many of what we call "stable postlaryngectomy patients" just have a stoma with no trach, and you can actually see the airway quite nicely. If that swab breaks off, that's the only airway that they have, so you have to be really careful.
Glatter: If you only had one swab and had to sample, which site would you go to? If you had to choose one, would use the nasopharynx or, say, a stoma from a laryngectomy patient?
Shapiro: I think you're getting more with the nasopharynx. There's not necessarily sputum in a stable laryngectomy patient, and you may not get a good enough sample. It's very irritating, so they're going to cough if you touch their airway with the swab. I would still choose the nasopharynx.
Glatter: Great. I want to thank you for this interview. It has been very instructive, and we really appreciate your time in explaining these pitfalls. Thanks for joining.
Shapiro: Pleasure to be here. Thanks.
Robert D. Glatter, MD, is an attending physician at Lenox Hill Hospital in New York City and assistant professor of emergency medicine at Zucker School of Medicine at Hofstra/Northwell in Hempstead, New York. He is an editorial advisor and hosts the Hot Topics in EM series on Medscape. He is also a medical contributor for Forbes.
Nina L. Shapiro, MD, is the director of pediatric otolaryngology at the UCLA Mattel Children's Hospital, and a professor of head and neck surgery at the David Geffen School of Medicine in Los Angeles, California. She is a regular guest on the Emmy Award–winning television show The Doctors, and her work has been featured and published in numerous publications, including the Wall Street Journal and the Los Angeles Times.
Medscape Emergency Medicine © 2020 WebMD, LLC
Any views expressed above are the author's own and do not necessarily reflect the views of WebMD or Medscape.
Cite this: How to Swab a Patient for COVID After a Tracheostomy - Medscape - Nov 11, 2020.