What is a huff? Huffing is one of the more difficulty techniques to learn for airway clearance. I find that most of my patients have trouble mustering the strength to perform a good solid huff. It’s not just that it is unfamiliar, but also that it takes diaphragm strength that they just don’t have. But when they nail it, it is so effective! So I keep teaching it even though it’s hard.
Huffing is part of the Forced Expiratory Techniques (FET). The name pretty much describes itself. You force an exhalation to mobilize secretions. Like many other airway clearance techniques, they are better when used in conjunction with other techniques, not independently.
So, along that line, when used as an FET, huff tend to be followed by diaphragmatic breathing or deep breathing cycles, or huffs may be incorporated in to the active cycle of breathing to achieve a similar outcome. There are several variations of the ACBT that can be implemented, but you can read about the standard one here. FET is also a great technique to place in between bouts of vibration or percussion, as evidence shows that this combination is significantly more effective when performed together, especially when used for long term management.
I’ve found the best way to teach it is to just show them. It’s kind of a silly sound and people tend to be a bit shy about performing it alone. I show them first so I’m the one to look silly, and then we do it together. When I teach a patient to huff as part of their FET home program, there are a few cues I like to use:
- The Ho, Ho, Ho
- I ask the patient, “What does Santa Claus say?” Now I will admit that some people (it’s rare) do actually get this wrong and say “Merry Christmas”. So, I’ll give them the answer. Then they say, “Ho, Ho, Ho”.
- Then I ask them to say it again but pretend Santa has smoked for 40 years.
- This pretty much always works and is easy for a patient or caregiver to remember.
- The Culturally Sensitive Approach
- I ask the patient to force a wheeze using their belly muscles to push air forcefully.
- As long as I’m also demonstrating at the same time, this also almost always works. It does tend to require cues for increased force production.
Here’s what a decent huff sounds like:
What’s the difference between a huff and a cough?
That’s a really simple answer (not really my style, right?). The difference between a huff and a cough is an open glottis. Holding the glottis open lets air flow freely through the trachea, producing the airy huff sound.
Why not just cough?
Well, coughing is exhausting. My patients cough all day as it is and they really don’t want to cough more than they have to. They typically already have irritated airways from coughing or supplemental oxygen. Of course I also teach them energy conservation when it comes to coughing, but sometimes we need something a little less aggressive that can be performed more frequently for airway clearance. Huffing is equally effective at clearing secretions when compared to coughing, but is less strenuous when performed properly.
In some patients, too much huffing can result in collapse of lung tissue due to the back pressure against the glottis. Huffing doesn’t generate such high pressure, so the risk of collapse is less.
Making it personal…
Another variation you can play with is huffing at different lung volumes. Huffing at high lung volumes (when your lungs are mostly full of air already) helps to mobilize secretions in the peripheral regions of your lungs because the air has filled up those spaces and you utilize the huff the vibrate that air. Huffing at low lung volumes (when there isn’t much air in your lungs) helps to focus secretion mobilization to the larger more central airways to move those gathered secretions out.
You would typically want to huff at higher volumes first to mobilize peripheral secretions inward and then huff at lower volumes to mobilize what you’ve collected so it can be expelled. However, that depends on what the patient needs. If you are hearing ronchi on your auscultation, you’d probably want to huff at low volumes to clear the larger central airways before anything else.
Take a listen to the different between the two. When huffing at high lung volumes, you have your patient take a deep breath in and then huff it out. But, when huffing at low lung volumes, you have the patient breathe in and then most of the way out before the huff.
Remember, FETs are aerosol-generating procedures, so be sure you and your patient are masked and in proper PPE. Like I said, these techniques are effective, so you’ll probably need some tissues handy also, or a cup if you are needing to collect a sample. And, as always, don’t forget to auscultate afterwards to assess progress!
Very useful and very effective, the best kind of tool to have in your toolbox! What is your favorite Pulmonary Rehab Tool we have discussed so far? Tell me in the comments!
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D’Abrosca F, Garabelli B, Savio G. (2017). Comparing airways clearance techniques in chronic obstructive pulmonary disease and bronchiectasis: positive expiratory pressure or temporary positive expiratory pressure? A retrospective study. Brazilian Journal of Physical Therapy. 21(1):15-23. DOI: 10.1016/j.bjpt.2016.12.001.
Fink J. B. (2007). Forced expiratory technique, directed cough, and autogenic drainage. Respiratory care, 52(9), 1210–1223. Retrieved from http://rc.rcjournal.com/content/52/9/1210/tab-pdf
McIlwaine, M., Bradley, J., Elborn, J. S., & Moran, F. (2017). Personalising airway clearance in chronic lung disease. European respiratory review : an official journal of the European Respiratory Society, 26(143), 160086. https://doi.org/10.1183/16000617.0086-2016
Torres-Sánchez, I., Cruz-Ramírez, R., Cabrera-Martos, I., Díaz-Pelegrina, A., & Valenza, M. C. (2017). Results of Physiotherapy Treatments in Exacerbations of Chronic Obstructive Pulmonary Disease: A Systematic Review. Physiotherapy Canada. Physiotherapie Canada, 69(2), 122–132. https://doi.org/10.3138/ptc.2015-78
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