ABGs (Part 1)

This is the first post in a two-part series about understanding and interpreting arterial blood gases! If you want the rest of the post, you’ll have to check back next week!

I’m getting real science-y again!

So, just a heads up: my undergraduate degree was in chemistry. Kind of by accident, I took a lot of chemistry courses. I know that sounds a bit weird, but I had an odd schedule and chemistry classes filled the gaps. I didn’t even necessarily like them, but I did gain a lot of understanding when it came down to organic chemistry and physiological concepts. When it came time to learn about acid-base buffers, I was ahead of the game. When it came time to apply that to the human body, I was all over it. That’s how I view arterial blood gases. It’s like a chemistry homework question from undergrad. You just have to apply the same conceptual framework every time and you will figure it out. So, I’m going to teach you that conceptual frame work, step by step. I promise, it won’t be that hard!

Arterial blood gases (ABGs) are performed when it is suspected that a patient may be in alkalosis or acidosis (depending on the circumstances). It is a relatively painful arterial puncture (…so I’m told. I’ve never had one, but all my patients say it hurts much more than venipuncture). The arterial blood is oxygenated (unlike venous blood), so it shows you a bunch of information about how the acid-base buffer system in the human body (the BiCarb Buffer System) is functioning. These tests are regularly performed on people who have chronic lung, heart, or kidney disease, because all three of these organ systems are intricately intertwined and have significant impact on the oxygenation of tissues. However, there are some other diagnoses that will result in a patient requiring ABGs to be checked and we will talk about some of those here, too!

H+ + HCO3- < — > H2CO3 < — > CO2 + H2O

The above equation basically runs our body chemistry. We want to hang out around the middle. Humans have a VERY small window in which we can properly function, but we’ll talk more about that later. For the basic purposes of this post, we will say that humans exhale CO2 and inhale oxygen. We know there are lots of other gases involved, but we are going to focus on those for now. So you can imagine, if we exhale too much, we lose too much CO2 and we fall too far toward the left. If we don’t exhale enough, we accumulate too much CO2 and we fall too far toward the right. CO2 has a higher affinity for hemoglobin than oxygen (that good old oxygen-hemoglobin dissociation curve from physiology soooo many years ago…) so we have to focus on CO2. I know, all of this sounds a bit overwhelming. There is a lot to know, but I promise, I will break it down and make it easy for you!

Oxygen-Hemoglobin Dissociation Curve - Respiratory - Medbullets Step 1

Basically, what this O2-HbG dissociation curves shows us is that the more oxygen we have, the easier it is to bind more oxygen. But as we lose oxygen and bind more CO2, it becomes easier to lose oxygen and bind more CO2. This is called the Bohr effect and, as you can see, it can hit a critical point. You can see that it is also effected by temperature and pressure. You can probably infer that profound anemia would also impact this curve. You can read more here about how the amount of hemoglobin affects your oxygen levels.

Chemistry is a really gray area in that it does its best to estimate amounts, but the reality is that, in a living system, they are estimates in time. Think about water. At any given time, you have liquid water, H2O, as well a gaseous hydrogen and oxygen molecules floating around binding and unbinding with each other in all different combinations (like H2O2 – hydrogen peroxide which is very volatile) in the same container. Water is a very stable molecule, but many bodily substances are not. Let’s talk about acidosis and alkalosis. We need to define a couple terms in case you aren’t as fresh on your chemistry:

pH. Typically thought of as “how acidic or basic something is”. A low pH indicates acidic, a high pH indicates basic. Normal human pH is 7.34 to 7.45.

Acidosis. When too many hydrogen ions [H+] build up in the body in some form (carbonic acid or lactic acid). Hydrogen ions are the basic unit of an acid. Body pH would be below 7.35.

Alkalosis. When too much bicarbonate [HCO3-] builds up in the body. Bicarbonate is a base. Body pH would be above 7.45.

Now that you’ve got the basics, let’s do some application.

Respiratory Acidosis. Results from hypoventilation leading to increased CO2 in blood and decreased pH. Things that cause this condition include pretty much anything that decreases your ability to remove CO2 (diffusion and ventilation). That would include respiratory suppression from drug usage, Giullian-Barre Syndrome, a brain injury to respiratory center, or airway obstruction (acute or chronic).

However, this condition can also be caused by an increased oxygen metabolism without compensating with a change in ventilation. What might cause that? A large amount of tissue damage requiring a large amount of healing such as in burns or sepsis (like COVID-19). When it presents acutely, respiratory acidosis is a medical emergency and requires immediate medical intervention. Acute-on-chronic respiratory acidosis would also require emergency medical intervention.

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Wait… Did Doctor B just say that a medically emergent condition can be chronic? Yep, I did. Respiratory acidosis can be chronic in patients with COPD and some other obstructive airway conditions. Their bodies get so used to being oxygen deprived that they no longer compensate with an increased respiratory rate. Respiratory acidosis just becomes their normal state. Arterial blood gases then really come in to play to establish when someone becomes a CO2 retainer. This is a HUGE safety factor and one of the most important reasons rehab professionals need to be able to interpret ABGs. Please read this post on CO2 retainers and this post on oxygen saturation for more information.

Respiratory Alkalosis. This happens when hyperventilation results in the removal of too much CO2 which results in increased pH. Respiratory alkalosis is rarely life threatening (unless the patient is also in acute respiratory distress) and can be easily treated. Panic attacks are sometimes characterized with these symptoms, and can result in people passing out, which effectively stabilizes their respiratory rate and they return to normal.

This is one of the complications for patients who have COVID-19. They are in respiratory distress due to low oxygen levels, but then can also push too far in to alkalosis by breathing too quickly trying to get more oxygen (which won’t be effective due to parenchymal damage). This can also be a complication in the process of recovering from COVID-19, as patients can demonstrate oxygen starvation resulting in similar behavior. Treatment is fairly simple if the patient isn’t in ARDS: reduce the respiratory rate or use a rebreather. These treatments can be achieved in a few different ways:

  • Reducing respiratory rate could be achieved by breathing control, diaphragmatic breathing, or increasing oxygen titration (as able). Sometimes distraction, prayer, meditation, biofeedback, or education can help with this also.
  • Using a rebreather is probably what you think of when you see someone breathing in to a paper bag. We, of course, would use medical equipment for this type of thing, with different rebreather masks available, but the concept is the same. The patient breathes in some of the CO2 they exhaled in to the bag/mask and the concentration of CO2 in their blood increases.

When treating respiratory alkalosis, you have to monitor to ensure your patient doesn’t swing the opposite direction in to respiratory acidosis by increasing their CO2 levels too much.

Metabolic acidosis. This results when the body produces too much acid and the kidneys cannot remove it quickly enough which results in a decreased pH. As with respiratory acidosis, this is a medical emergency, and can result in coma or death. Metabolic acidosis can be caused by several factors: rhabdomyolysis, starvation, exercise bulimia, aspirin (abbreviated ASA = acetyl-salicylic acid) overdose, etc… as these processes result in acid build up. Oddly, overuse of the laxative polypropylene glycol (MiraLax) that ALL of your patients are on can also cause metabolic acidosis due to the chemical breakdown of this substance. I know that sounds weird, because you’d think if they were getting rid of all that stomach acid, they would become alkaline, but that isn’t the case with this specific agent. MiraLax is metabolized in to an acid. Other causes may include kidney failure and acute/chronic ethanol intoxication, but many causes are possible and it is difficult to detect without ABGs.

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However, just like with respiratory acidosis, metabolic acidosis can also become chronic. This can happen in patients who have uncontrolled Type 2 Diabetes Mellitus. We just have a different name for it (ketoacidosis). Ketoacidosis can be acute as well, so you still need to be calling for medical help. Thankfully, there is something you can do for these patients:

  • If you happen upon someone who is in metabolic acidosis, you can help them temporarily (long enough to call 911 and get an ambulance to them) as this condition can be compensated using hyperventilation! This works by expelling the CO2 making up carbonic acid in their bodies to slightly offset the acid levels. Like I said, this is temporary and only buys time. It is NOT a cure! Metabolic acidosis will persist until treated.

Metabolic alkalosis. The removal of too much acid (or too many H+ ions) from the body which increases pH. Metabolic alkalosis can be caused by vomiting, diarrhea, severe diuresis, dehydration, or, in rare cases, loss of sodium in sweat glands solely associated with cystic fibrosis. Metabolic alkalosis cannot last long if the kidneys are well functioning, as the kidneys will compensate by retaining more H+ ions and Na+ ions. This condition typically presents with low blood pressure, low blood volume, elevated heart rate, and lethargy. Patients may be significantly orthostatic. However, it can also present with hypervolemia in the case of heart failure patients in fluid overload depending on the electrolyte factors involved and the kidney function impairments.

This condition can also be compensated in the same way respiratory alkalosis can be compensated: with use of a rebreather or by reducing the respiratory rate.

As it so happens, though, I see people with metabolic alkalosis ALL THE TIME who need medical intervention. My typical caseload involves people with mulitple complex chronic diseases. For many them, their kidneys are NOT functioning properly. For most, medical intervention takes the form of IV fluids with different levels of sodium (Na+), potassium (K+), or lactic acid (Ringer’s Lactate solution). For those with heart failure, they can actually be in fluid overload but not have any usable fluid so be exhibiting the symptoms of hypovolemia at the same time. This becomes a delicate dance of giving them enough usable fluid while simultaneously pulling off the unusable fluid, which has to be done under close observation in the inpatient setting.

OK, so now that you’ve got the basics, I’m going to let you marinate on that for a while. In Part II of this post, we will talk about compensated conditions, how to read ABGs, and how to tell what condition your patient is in. This will help you understand when it is safe to treat them based on these values. Keep checking back!

How often do you get the chance to read ABGs before the ordering provider? How do you use that information? Tell me about it in the comments!

More from the Pulmonary Rehab Toolbox…

Postural Drainage

We’ve all seen that dreaded picture in our textbooks… All the human figures laying in so many different positions with pillows and tables tilted all over… and I very clearly remember thinking, “How on earth am I supposed to remember all of those?” Well, good news. You really don’t have to. It’s great if youContinue reading “Postural Drainage”

Spilling the Box of Pearls: All the Tips on Supplemental Oxygen Management

In my recent post on COPD management, I mentioned that there are some really important parts of supplemental oxygen management that you need to be aware of and consider in your practice. If you are assisting patients who utilize supplemental oxygen regularly, you need to keep these things in mind. You also may be workingContinue reading “Spilling the Box of Pearls: All the Tips on Supplemental Oxygen Management”

Chronic Disease Part 2: Chronic Obstructive Pulmonary Disease (COPD)

This is part 2 in a multi-part series on the role of Rehab Providers in the management of chronic disease. Don’t forget to check out Part 1: Heart Failure! Chronic Obstructive Pulmonary Disease is a widely diagnosed disease of the lungs that includes the diagnoses of emphysema and chronic bronchitis. COPD can be caused byContinue reading “Chronic Disease Part 2: Chronic Obstructive Pulmonary Disease (COPD)”


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Kaufman, D. (2020). Clinical Education: Interpretation of Arterial Blood Gases (ABGs). American Thoracic Society. Retrieved from http://www.thoracic.org/professionals/clinical-resources/critical-care/clinical-education/abgs.php

Lewis, J. (2020). Acid-Base Disorders. Merck Manual Professional Version. Retrieved from https://www.merckmanuals.com/professional/endocrine-and-metabolic-disorders/acid-base-regulation-and-disorders/acid-base-disorders

Follow @DoctorBthePT on Twitter for regular updates!

Aerosol Generating Procedures

The long awaited clarification on aerosol generating procedures for physical therapists and physical therapist assistants has finally dropped! The APTA just released its professional guidelines for what portions of physical therapist and physical therapist assistant care equates to an aerosol generating procedures, therefore requiring increased PPE for procedure performance to ensure clinician safety. On April 13, 2020, the Centers for Disease Control (CDC)  updated their guidance to indicate that aerosol generating procedures (AGPs) are medical procedures that are “more likely to generate higher concentrations of infectious respiratory aerosols than coughing, sneezing, talking, or breathing” and result in “uncontrolled respiratory secretions.” However, exactly what that meant when it came to Physical Therapist services was unclear. Most people, even in the medical world, forget that we do so much more than exercise.

In my Webinar on Combatting COVID, I was very clear that the WCPT guidelines listed exercise as an aerosol generating procedure. However, many healthcare organizations in the United States do not observe the WCPT guidelines, so were defaulting to the CDC guidelines which are silent on “exercise” as a specific term. The CDC guidelines did provide a nice table (which you can view here) that was supposed to guide which level of PPE all healthcare providers should be wearing. But, let’s be real. MOST healthcare providers are not performing the type of work-intensive and time-intensive interventions that we are in the rehab field. Respiratory therapists are definitely taking the brunt of the risk with the number of AGPs they regularly perform. However, many of these don’t take nearly as much time as what we need to perform. Time spent in exposure is one of the most important factors when deciding level of risk involved with a procedure (based on the CDC table mentioned above).

“Mobilization in and out of bed, ambulation, therapeutic exercise, and other similar physical therapist interventions are common procedures performed in intensive care units, hospital wards, inpatient rehabilitation units, other facilities, and patient’s homes. These sessions, which can last 30 minutes or more, result in extensive close body contact; for some procedures PTs and PTAs place their faces within inches of the patient’s face to ensure safety (Loeb, 2004).”

APTA (2020)

But we also need to talk about proximity. When we are transferring a patient, we are ALL UP IN THEIR BUSINESS. We are face to face, we are ear to ear, we are body to body. And for our SLP friends, you are very literally all up in their grill. So proximity increases the risk of allowing droplets to land in your muscosa (ew…). Many healthcare professionals get to stand back and observe, or take vitals using an automated machine and not have to touch. Even starting an IV, you can at least be at arms length. But not while working on perineal hygiene… NOPE. You are well within the danger zone.

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And finally, we are making the patient MOVE! We are working them harder than they may have worked in a several days, weeks, or months depending on the setting. We know from recent research that even talking can aerosolize viral particles in to droplet nuclei, so can you just imagine with the huffing and puffing of sit to stands will do? I know people are pretty upset about gyms being closed but, take it from a PT, there is darn good reason for gyms to be closed! You are in a small space with several people (even at 6 feet apart) all huffing and puffing increased lung volumes, forces, and depths, aerosolizing droplet nuclei in clouds, over and over and over again. There is no amount of environmental control that could save you. But, here comes therapy, down the hall in full PPE, ready to work the sickest folks and hang out them in that cloud for 30 minutes or more. So, the obvious answer was yes, therapy interventions OF COURSE are aerosol generating procedures. But you didn’t have to convince us of that…

“Assisting a patient in moving from supine to sitting increases the depth and rate of ventilation, and creates a shift in ventilation and perfusion patterns, in a manner that often elicits uncontrolled respiratory secretions and/or cough reflex. Rolling, proning, and supinating a patient in bed also are considered aerosol-generating procedures.”

APTA (2020)

We don’t really need to just focus on exercise and physical activity. Patients with COVID-19 are critically ill. Many of the patients I see regularly are critically ill because I work with many people who have complex chronic diseases. That means there is a significant likelihood that CPR may be needed at some point in time. I have had plenty of coworkers who have arrived at a home and had to start chest compressions. I’ve been a first responder to so many people just randomly out in public at train stations, sporting events, or even weddings. But then, to add strenuous physical activity on top of a critical illness, we are upping the ante (because that’s what we are trained to do). In the event we do have to perform CPR, if we are not already donned in appropriate PPE, the APTA has made it clear that it takes approximately 6 minutes to do so. That’s 6 minutes our patient goes without oxygen to their brain. That, my friends, is not a patient that will survive. Those 6 minutes are crucial so we need to be ready to go at the onset.

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Ultimately, rehab clinicians literally have to do all three things that create the most aerosol AND places the provider at highest risk. Yet there was no clear statement from any agency or authority, only “exercise” listed on the WCPT guidelines. Many saw that as not including physical activity like transfers or bed mobility. Thankfully, ASHA released a document clarifying the provision of Speech-Language Pathologist Services in regards to aerosol-generating procedures to set guidelines for their own profession. So, I (and many others, I’m sure) have just been waiting…

“Across respiratory conditions, mobility and exercise are known to be a form of airway clearance, often resulting in uncontrolled respiratory secretions and bouts of spasmodic coughing (Strickland, 2013).”

APTA (2020)

I hope everyone takes a read on this one, prints it out, takes it to work, posts it in the office, in the hallways, screams it from the mountaintops and whatever you need to do to make sure you get the proper equipment you need to keep yourself safe when treating patients. The highest number of new cases of COVID-19 are among those 20-40 years old. There are many people in the ICU within that age range including several without underlying conditions. I’ve said it before, and I’ll say it again, COVID doesn’t discriminate. Please take necessary precautions and stay safe out there.

Read the original publication here:

I know it’s been a long time coming, but are you getting the proper PPE yet? Let me know in the comments!

It’s Getting Hot in Here: Body Temperature

How many times have you had your temperature taken lately? I think I’ve had my temperature taken thousands of times in the last few months. We are seeing the increased use of forehead scanning thermometers and temporal scanners, all the non-contact forms of temperature assessment, to screen folks for COVID-19 symptoms upon entry to anyContinue reading “It’s Getting Hot in Here: Body Temperature”


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APTA. (2020). Taking Precautions for Mobility and Exercise as Potential Aerosol-Generating Procedures. Retrieved from https://www.apta.org/patient-care/public-health-population-care/infectious-disease-control/precautions-mobility-exercise-potential-aerosol-generating-procedures

Follow @DoctorBthePT on Twitter for regular updates!

The Duet Device

Have you seen an Acapella Duet before? This is another one of those things I wish I could hand out to maybe half of my patients.

  • A Duet device is a special kind of Positive Expiratory Pressure (PEP) that provides resistive oscillatory pressure to exhalation which promotes increased lung volumes due to re-inflation of collapsed airways, but in addition to positive pressure reinflation, it also allows for the nebulization of medications simultaneously.
  • Typically given by RT while a person is hospitalized to increase efficacy and effectiveness of nebulizer treatments, however, patients are not typically instructed on how to use them independently. Or, if they are, they don’t remember by the time they get home or to their next facility.
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Patients who benefit from Duet use:

Cystic Fibrosis
Chronic Bronchitis
Pre/Post Lung Transplant

Or anyone doing nebulizer treatments. However, nebulizer treatments are not being recommended for patients with COVID-19, unless they are in a closed environment (like a negative pressure room with only medical professionals in attendance) as nebulizers aerosolize viral particles into the air.

What does the evidence say about using PEP with nebulizers? Does it actually work?

  • In Cystic Fibrosis patients, nebulized medication deposition decreased but distribution increased when a duet device was used.
  • In Asthma patients, nebulized medication deposition increased and distribution increased, specifically to the middle and lower thirds of the lungs when a duet device was used.
  • Use of PEP in patients with COPD reduces post-exercise dyspnea and increases length of time the patient is able to participate in exercise. PEP also reduces dynamic hyperinflation, even at only 5cm of H2O of pressure.
  • In healthy subjects, tracers were used and researchers found that using PEP with nebulized medications improves membrane permeability (diffusion) of the medications. They also found that higher pressure were tolerable, from 10-20 cm of H2O.
  • As we discussed in this blog post, there is no evidence informed protocol for PEP use yet.

How to Set Up the Nebulizer with the Duet for treatments:

As more patients are coming home from acute care after COVID-19, and hopefully testing negative, some will continue to require ongoing treatment for the damage done to their lungs. This may be in the form of nebulized medications once they are no longer carrying the virus.

To improve your patients ability to participate in physical activity or exercise, they should be performing their nebulizer treatments at least 15-20 minutes before activity. This may mean that you need to instruct them how to do this and them as them to make sure it is done before you see them for the next visit. This gives the medications (typically bronchodilators) time to do their job: open up the airways to improve ventilation, and hopefully diffusion, and hopefully perfusion.

I always request duet devices for my patients who are running nebulizer treatments, if I feel they also need airway clearance or dynamic hyperinflation management. Have you ever used duet devices? Tell me about it in the comments!

More from the Pulmonary Hygiene Toolbox…

ABGs (Part II)

So, now that you’ve read all the basics about ABGs in the first post, here is a little more about interpreting lab values and how to determine compensated conditions. This is where it gets fun! First off, let’s take a look at what NORMAL lab values probably look like: pH: 7.35-7.45 Partial pressure of oxygenContinue reading “ABGs (Part II)”

ABGs (Part 1)

This is the first post in a two-part series about understanding and interpreting arterial blood gases! If you want the rest of the post, you’ll have to check back next week! I’m getting real science-y again! So, just a heads up: my undergraduate degree was in chemistry. Kind of by accident, I took a lotContinue reading “ABGs (Part 1)”

Aerosol Generating Procedures

The long awaited clarification on aerosol generating procedures for physical therapists and physical therapist assistants has finally dropped! The APTA just released its professional guidelines for what portions of physical therapist and physical therapist assistant care equates to an aerosol generating procedures, therefore requiring increased PPE for procedure performance to ensure clinician safety. On AprilContinue reading “Aerosol Generating Procedures”


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Albuquerque, I. M., Cardoso, D. M., Masiero, P. R., Paiva, D. N., Resqueti, V. R., Fregonezi, G. A., & Menna-Barreto, S. S. (2016). Effects of positive expiratory pressure on pulmonary clearance of aerosolized technetium-99m-labeled diethylenetriaminepentaacetic acid in healthy individuals. Jornal brasileiro de pneumologia : publicacao oficial da Sociedade Brasileira de Pneumologia e Tisilogia42(6), 404–408. https://doi.org/10.1590/S1806-37562015000000320

Alcoforado, L, et al. (2013). Evaluation of lung function and deposition of aerosolized bronchodilators carried by heliox associated with positive expiratory pressure in stable asthmatics: A randomized clinical trial. Volume 107, Issue 8, Pages 1178–1185;

Laube, B, et al. (2005). Positive Expiratory Pressure Changes Aerosol Distribution in Patients with Cystic Fibrosis. Respiratory Care, 50 (11) 1438-1444

Padkao, T., Boonsawat, W., & Jones, C. U. (2010). Conical-PEP is safe, reduces lung hyperinflation and contributes to improved exercise endurance in patients with COPD: a randomised cross-over trial. Journal of physiotherapy56(1), 33–39. https://doi.org/10.1016/s1836-9553(10)70052-7

Ubolsakka-Jones C, Pongpanit K, Boonsawat W, Jones DA. Positive expiratory pressure breathing speeds recovery of postexercise dyspnea in chronic obstructive pulmonary disease. Physiother Res Int. 2019;24(1):e1750. doi:10.1002/pri.1750

Follow @DoctorBthePT on Twitter for regular updates!


I spent some really great times as an educator in a heart and lung transplant program at a large hospital system. Specifically, I was a therapy educator. I taught PTs, PTAs, OTs, COTAs, and SLPs what they needed to know to safely provide rehab to patient after heart and lung transplants. I saw so many of these patients both at our hospital and at their homes and helped transition them to cardiac and/or pulmonary rehab programs when they were ready. I loved working with this population! I mostly enjoyed the complexity of this type of case. Most of the time, they had a long course of illness prior to transplant. Some of them I even had the honor of pre-habbing prior to transplant and it was great to see them make that transition. After transplant, they felt like a new person!

But regularly seeing patients after transplant means knowing a specific set of symptoms to look out for because you have to be constantly monitoring for rejection. We will talk much more about transplants in another post but, some of those symptoms include:

  • Resting Heart Rate less than 60 bpm
  • Fatigue
  • Shortness of breath at rest
  • Malaise
  • A feeling of chest pressure
  • Dry cough
  • Decreased exercise or activity tolerance
  • A decrease in lung function of 10% or more

Let’s take a closer look at that last one. How can we know if someone’s lung function has decreased by 10%? Well, you have to look at a measure of lung function. The one we used was FEV1, or forced exploratory volume in 1 second. This is the percentage of air you are able to forcibly exhale from your lungs in 1 second, after taking a maximal inspiration, and in comparison to your predicted ability. This may seem like a strange measurement, especially since it’s different for everyone and based on several factors, like your gender, but let’s break it down and you’ll see why it’s so important.

If you remember how lung volume works as I described in my video in dynamic hyperinflation, after you take a deep breath in, you have to get all that air out. And if you have an obstructive disease, you have to get even more out than what you put in. So the strength of your diaphragm begins to become a significant factor in your lung function. Therefore, FEV1 is a significant diagnostic factor for obstructive and restrictive lung disease. This also continues to be true after transplant. These patients are typically working with a weakened diaphragm from whatever disease state they experienced prior to transplant. As they rehab and heal, we expect their diaphragm strength to increase and their forced exploratory volume to increase. They no longer have trapped air to fight against because their brand new lung doesn’t (hopefully) have disease.

GOLD stage of COPDPercentage of predicted FEV1 value
Mild80 percent or above (in the presence of known disease)
Moderate50 to 79 percent
Severe30 to 49 percent
Very severe29 percent or less
GOLD, 2016

Everyone has a residual volume that just hangs out in the lungs so that part is normal. If your patient has a lung disease and they were able to get all our air out of their lungs in 1 second, then they probably didn’t have that much air in their lungs to begin with which would signal poor inspiratory volume, so we are targeting greater than 80%. Some healthy people can even get as high as 120% of their predicted value! Remember, this isn’t a percentage of the volume you have its a percentage of the expected volume you can exhale.

That’s all fine and good, but how the heck do we measure something like that without PFTs (pulmonary function tests)? One of the cool things our hospital did was utilize a device that went home with the patient to regularly measure lung function. It actually did a whole bunch of other things, too, like record and remind them about their medications. If you’ve ever seen someone after transplant, you know they have a ton of medications that have to be taken a thousand times every day. It was called a Spiro PD.

As cool as this device was, it was incredibly difficult to use properly and patients tended to get measurements that were all over the map. I found that they needed to be properly trained in how to take a deep breath and perform an FEV1 test with their new lungs! So here are some tips to generally improve FEV1 and overall lung function. You probably already do some of these things and just don’t know it!

  • Stand up. This allows you to utilize your full lung volume better, all other factors being normal. If you are sitting, several postural factors can influence your ability to take a deep breath. This particular portion can become problematic if your patient has balance impairments, but they can always hold on to a hemi-bar, counter top, or their walker. Make sure they aren’t weight-bearing through their hands on whatever surface you are using because this facilitates accessory muscles. A maximal inspiration typically requires some trunk movement in to the posterior space, so be sure to guard them closely. Don’t make the gait belt too tight or you will impact their inspiratory volume.
  • Use a mirror. Patients sometimes have no idea what they are doing when they breathe. Honestly, who pays attention to that, anyway? We jus breathe and get on with things. But we all know that patients develop some pretty serious compensations when disease is present which results in them changing their breathing patterns to less efficient techniques. Putting them in front of a mirror and utilizing this visual feedback can be really helpful in remediating those inefficient patterns. If you are using a bathroom mirror, this also allow them to use the counter top for support as needed.
  • Pre-training in diaphragmatic breathing. Especially if your patient has experienced a pulmonary disease, they will have the need for diaphragm retraining. However, this is not limited to patients in a disease state. Diaphragm training can be helpful for athletes, too. If you can trigger that diaphragm to engage at the proper moment and increase the strength of contraction, you can help your patient improve their inspiratory volume. We will talk about this in greater detail in a different post. I find tactile cues to be really helpful, though! Find things that really help them focus on breathing OUT!
  • Be ready ahead of time. So many times, I would be using the SpiroPD to test my patient’s FEV1 and they would place it down on the table or counter or the seat of their walker and then have to go hunting for it when it was time to breathe out. This wasted so much of their energy and ability to forcefully exhale. If you are using a measurement device for FEV1 or other lung function measure testing, have it in the patient’s hand, ready to go during testing so they don’t waste any energy.
  • Coaching. Spirometry testing isn’t easy and patients are quick to give up if they don’t know how long this is actually going to take. When doing an FEV1 test on the Spiro device, the device needs to calculate ALL the air the comes out, not just what comes out in 1 second. That means the patient has to keep blowing as long as they can, or as long as the machine needs them to. THIS IS SO HARD! They will need you to coach them in continuing the test as long as needed. It will feel uncomfortably long!

Something I love to do with patients who have a SpiroPD device is have them do their normal testing with all their altered posters and inefficient techniques while I was with them. We would review their results which were typically pretty awful (30-40%), then train them, reposition them, and retest them. This almost always showed significant improvement in their measures. (I love using the test-retest method to show improvement and the value of our interventions! I talk about that here, too!) And, if it didn’t, I knew something was actually wrong and I could confidently report to the transplant team.

Another thing we do is some magical math to look at lung function. We take FEV1 and divide it by FVC (forced vital capacity). We want this ratio to be pretty close to 1 to indicate healthy lung function. If you would like to calculate your predicted FVC, FEV1, or many other lung function measures, you can do that here or here! My predicted FEV1 is 3.56 liters! So I would need to do a spirometry test to see what percent of that I actually get and that would be my clinical value.

Northwestern Medicine

What got me on the track of talking about lung transplants? Well, I recently read an article about the first patient to receive a lung transplant due to COVID-19. A woman in her 20’s was admitted to the hospital for acute respiratory distress due to COVID-19. She had been on a ventilator for two months and was still failing. They transitioned her to ECMO, but she continued to decline. Her kidneys and liver started to fail and there was no hope of returning to normal. The damage to her lungs became irreversible. Doctors found that not only did she have a viral COVID-19 infection, but also ended up with bacterial abscesses in her lungs. After the viral infection had cleared, they determined the only way to save her was a double lung transplant. That picture above is her lungs prior to transplant. You can see that the left lung is nothing but giant air pockets and the right one is completely full of consolidation of varying types. All in all, nothing here is viable.

The next picture is of a lung removed from this twenty year old female. This lung is one of the most damaged I have seen. It’s like the lung tissue liquified. It’s hard to even describe. If you don’t want to see it, keep scrolling, but in case you do, here you go.


Northwestern Medicine

After transplant, this woman began to make a significant recovery. Her major organ systems began to heal and was working on coming off of ECMO while rehabbing. She did begin to show some of those signs of rejection we talked about earlier, but the anti-rejection medications seemed to be working well. She has a long road ahead of her fo many reasons. She was intubated and ventilated in the ICU for more than two months so she was significantly deconditioned. So what’s the overall outlook?

Well, patients who undergo lung transplant have about a 50% chance of surviving five years afterward. That number is improving slowly as the medical community gets better at interventions aimed at rejection, but her odds are still better than what they were prior to transplant where she had, at best, days before dying of multisystem failure. Her transplant candidacy was due to her very young age and lack of comorbid conditions, as well as her severe decline. I realize that, for those that are familiar with the transplant world, this could be somewhat controversial. People wait years for lungs and many never get them.

For those who are not familiar with the transplant system, this is not a go-to intervention. You have to have transplantable lungs available which means people have to be dying. You have to have a donor match. You have to have lungs that haven’t been infected with COVID-19. And you have to have a patient who is healthy enough (other than COVID-19) to receive the lungs. They also have to be generally the right size (although lungs can be resized to a point). Similar to ECMO, this is a literal last resort. This type of intervention takes a large team, including an extra set of team members from the transplant team, like social workers, transplant surgeons, specialized nurses and rehab providers, in addition to all the other wonderful medical professionals and family involved. The transplant team from Northwestern that perform the transplant on this women spent two and a half days just repairing the donor lungs she received to ensure they were the best quality for her.

What are some techniques you use to improve lung function? Tell me about them in the comments!

More from the Pulmonary Hygiene Toolbox…

The Duet Device

Have you seen an Acapella Duet before? This is another one of those things I wish I could hand out to maybe half of my patients. A Duet device is a special kind of Positive Expiratory Pressure (PEP) that provides resistive oscillatory pressure to exhalation which promotes increased lung volumes due to re-inflation of collapsedContinue reading “The Duet Device”


I spent some really great times as an educator in a heart and lung transplant program at a large hospital system. Specifically, I was a therapy educator. I taught PTs, PTAs, OTs, COTAs, and SLPs what they needed to know to safely provide rehab to patient after heart and lung transplants. I saw so manyContinue reading “FEV1”


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Herman, C. (2020). 1st-Known U.S. Lung Transplant For COVID-19 Patient Performed In Chicago. Shots: Health News from NPR. Retrieved from https://www.npr.org/sections/health-shots/2020/06/12/875486356/first-known-u-s-lung-transplant-for-covid-19-patient-performed-in-chicago

LUNGFUNKTION — Practice compendium for semester 6. Department of Medical Sciences, Clinical Physiology, Academic Hospital, Uppsala, Sweden. Retrieved 2010.

MedlinePlus. (2020). Transplant rejection. Retrieved from https://medlineplus.gov/ency/article/000815.htm

Thompson, E. G., & Russo, E. T. (2019) Forced Expiratory Volume and Forced Vital Capacity. University of Michigan Medicine. https://www.uofmhealth.org/health-library/aa73564

Yeung, J. C., & Keshavjee, S. (2014). Overview of clinical lung transplantation. Cold Spring Harbor perspectives in medicine4(1), a015628. https://doi.org/10.1101/cshperspect.a015628

Follow @DoctorBthePT on Twitter for regular updates!

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Remote Interventions for Pain Amid COVID-19

I am the first to admit that I find treating patients with chronic pain to be SO HARD. Thanks to a few helpful tips from friends and some continuing education, I can just barely touch my toe to the water. But, like many, I have been wondering how COVID-19 and lockdowns and masks and all of those things that have so drastically changed our way of life are changing the pain experience of my patients. Instead of making gross exclamations like so many new stories, I’m looking to the evidence.

Researchers in neuroscience, pain management, and psychology came together recently to write an article on this exact thing. How ARE patients who have chronic pain experiencing this pandemic lifestyle? How is it effecting their perceptions of pain? Is their life changing because of this? And what are the recommendations for what we do about it?

Over 500 people took part in the survey which asked them questions about their pain experience at different points during the pandemic (in the UK). Questions were asked pre- and post-lockdown and comparisons were made for pain behaviors, pain catastrophizing, and pain ratings. Psychological health conditions were also monitored.

The participants in the study were varied across ages and gender descriptions (including “other”), and the time period observed was about a month. It was amazing to me how much could change for the patients in only a months time with the onset of lockdown restrictions. Pain diagnoses were also varied with the highest number of participants demonstrating the diagnoses of “chronic widespread pain” and “chronic primary/secondary musculoskeletal pain”. However, some other more familiar categories were also present such as CRPS, chronic headache, and neuropathic pain.

Photo by Andrea Piacquadio on Pexels.com

Among other scales and tests, patients were asked to identify their pain on a 100 point VAS. The pre-COVID to post-COVID scores were significantly different, with a change of about 33 points in perceived pain on average across participants. That is a HUGE increase. Hoping all other factors were equal as much as they could have been, simply the presence of lockdown restrictions increased perceived pain by one third in patients who already had chronic pain. Now, I say perceived pain intentionally, as patients were also assessed in other ways to determine physical pain, which did not actually change throughout the time frame. The authors are clear that this demonstrates a psychological distress effect of lockdown restrictions on the perception of pain, not actual physical pain.

Patients with chronic pain were also eight times more likely to self-isolate and four times more likely to have a confounding illness during this time than their matched peers who did not have chronic pain.

Patients with chronic pain also experienced tiredness and loneliness twice as often, experienced pain catastrophizing twice as often, anxiety five and a half times as often, and depression nine times as often. They were also ten times more likely to reduce their physical activity.

“As pain catastrophizing was also the strongest predictor of self-perceived increases in pain in the full chronic pain cohort, this points to the need to make this a principle clinical outcome and
target for telemedicine pain management.”

Fallon, et al., 2020

The article has some recommendations for what we can provide remotely to help these patients. COVID-19 has opened the door to telerehab, telehealth, telemedicine, remote services, or whatever you have to call it to be able to bill for it. The reimbursement may not be awesome, but this method of providing care for rehab clinicians is here to stay. Do you know how I know that? Because Seema Verma said so. And if she is committing CMS to stick with it, most everyone else will follow suit. I have some information about telerehab on the resources page if you need more information about how to bring this in to your practice.


So, we know that opioids are NOT the answer to pain. But sometimes it feel like ONLY rehab clinicians actually know that because we still see them prescribed so often. However, this particular articles has some better options:

  • Now, like I said above, I’m no expert in chronic pain. But, I do know that education can be very effective in modulating and mitigating pain in certain populations and can be especially effective for patients who experience pain catastrophizing. This education can very easily be delivered through a remote platform.
  • Cognitive behavioral therapeutic techniques can also successfully be delivered remotely and are effective in the management of pain catastrophizing.
  • And the big one: physical exercise needs to be implemented. Not just to reorient fear-avoidance behaviors and provide neuromuscular re-education, but also to return patients with chronic pain to their prior level of function. Remember, we was above that they were significantly more likely to self-isolate and reduce their physical activity.

Now, obviously we don’t know if these interventions are AS effective when delivered remotely as they are in person, but that sounds like a really great research opportunity for some of my friends out there who primarily manage chronic pain! There is some preliminary evidence that telerehab interventions may be just as effective but we need more evidence.

We highlight the pivotal role of pain catastrophizing and reduced physical activity on the experience of people who live with chronic pain during lockdown conditions. This is significant because it points to potential clinical targets for therapeutic and behavioural interventions during the current, and future, crises.

Fallon, et al., 2020

If you aren’t treating patients remotely, yet, you need to start. Telerehab is the answer for chronic pain, now and in the future. Be ready to move with the rest of us.

What interventions are you providing remotely for your patients with chronic pain? Tell me about it in the comments!

More Reads…

Sternal Precautions

“Patients exchanging habits of activity for complete rest are likely to become rapidly worse.” This quote fuels my everyday. These words have informed nonsurgical and surgical rehabilitation and its evolution from handing out bed rest like Oprah hands out cars to getting people moving early and keeping them moving often. Here’s the crazy thing: ThisContinue reading “Sternal Precautions”


Gosh, this is a fine line… Especially in the patients I regularly see. A colleague and I often say, “If you have any more water, you’ll die. If you don’t have any more water, you’ll die.” This is actually a frequent education topic that I cover with patients. Scary? Yes, but true. So, why isContinue reading “Dehydration”

Diaphragmatic Breathing

Let’s talk about this super simple technique that can change everything. Diaphragmatic breathing is really just how we are all supposed to be breathing most of the time. The purpose of the diaphragm is to facilitate breathing. Diaphragmatic breathing improves gas exchange and increases lung volumes. These are all really good things if we need toContinue reading “Diaphragmatic Breathing”


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Ambrose KR, Golightly YM. Physical exercise as non-pharmacological treatment of chronic pain: Why and when. BEST PRACT RES CL RH 2015;29(1):120-130.

Fallon, N., Brown, C., Twiddy, H., Brian, E., Fank, B., Nurmikko, T., Stancak, A. (2020). Adverse effects of COVID-19 related lockdown on pain, physical activity, and psychological well-bring in people with chronic pain. medRxiv [made available pre-review]. Retrieved from https://www.medrxiv.org/content/10.1101/2020.06.04.20122564v1.full.pdf

Geneen LJ, Moore RA, Clarke C, Martin D, Colvin LA, Smith BH. Physical activity and exercise for chronic pain in adults: an overview of Cochrane Reviews. Cochrane Database Syst Rev 2017(4).

Piga M, Cangemi I, Mathieu A, Cauli A. Telemedicine for patients with rheumatic diseases: Systematic review and proposal for research agenda. Seminars in Arthritis and Rheumatism 2017;47(1):121-128.

Schütze R, Rees C, Smith A, Slater H, Campbell JM, O’Sullivan P. How Can We Best Reduce Pain Catastrophizing in Adults With Chronic Noncancer Pain? A Systematic Review and MetaAnalysis. J Pain 2018;19(3):233-256.

Westman AE, Boersma K, Leppert J, Linton SJ. Fear-avoidance beliefs, catastrophizing, and distress: a longitudinal subgroup analysis on patients with musculoskeletal pain. Clin J Pain 2011;27(7):567-577.

Follow @DoctorBthePT on Twitter for regular updates!

The (Very) Basics of Heart Auscultation

I was seeing a younger man in the home setting after a CABG x3 procedure. When I evaluated him, I was a bit frustrated because he had impaired cognition and had significant comorbidities for a younger man, none of which was in his referral information. Instead, I had the pleasure of just picking up on these things as I went along through my evaluation. His caregiver was reporting to me that he was very fatigued, very confused, very not himself since the surgery. He was a smaller man and did not seem to be exhibiting any signs of fluid overload. So I went on to what I typically look for in a patient immediately after CABG: orthostasis. In my article about Beta Blockers, we discussed how these medications are typically prescribed along with other medications after CABG procedures and this frequently results in orthostasis.

I began to perform the standard four-position orthostatic assessment that I mentioned in those posts and found him to be significantly orthostatic, to the point where I could not stand him up for more than a few seconds before he just sat down on his own due to being “lightheaded”. This seemed a bit extreme, but he was also likely dehydrated. However, yellow flags were going up in my head. I decided to investigate further. I noticed when taking his pulse and blood pressure that his heart rhythm was irregular so I took an extra listen to the main equipment.

La – Da – Da – La – Dub… Uh Oh.

This man’s heart sounded like an engine misfiring on all cylinders. There was some serious electrical disturbance going on here. I could hardly make sense of the sounds I was hearing. I contacted the cardiologist’s office and reported my findings (which probably sounded like I was completely unable to auscultate heart sounds… “uh, your patient’s heart isn’t demonstrating a typical contraction pattern upon auscultation…” was the best I could do without sounding just foolish).

Thankfully, his primary nurse arrived shortly after I discovered these findings and we had the opportunity to talk it over and attempt to figure it out. Ultimately, we decided he needed to go in and he was admitted.

So let’s take a look at heart auscultation. There are two main methods to do this, but, for the sake of simplicity, I’m just going to discuss this one. The “All Physical Therapists Move” method (also known as the “All Physicians Take Money” method) is the easiest to remember what you are actually listening to.

All. A is for Aortic Valve. Auscultating this structure will need to be done over the right second intercostal space at the sternal border. This is your “Dub”.

Physical. P is for Pulmonic Valve. Auscultating this structure will require you to place your stethoscope at the left second intercostal space, also at the sternal border. This is also your “Dub”.

Therapists. T is for Tricuspid. To auscultate this structure, place you stethoscope in the left fifth intercostal space, just lateral of the sternal border. This is your “Lub”.

Move. M is for Mitral (Also known as Bicuspid). To auscultate this structure, place your stethoscope in the left fifth intercostal space at midclavicular line. HOWEVER, this can be difficult to do with some female patients, and auscultation of sound may be difficult if the patient exhibits a bariatric build. So it can be easier to auscultate this valve at the same level, but at the midaxillary line. I typically perform this auscultation in this manner. This is also your “Lub”.

Next you need to know what you are listening for. There are four common heart sounds: S1, S2, S3, and S4. You really only want to hear two of them (S1 & S2), but sometimes you get a third or fourth thrown in. This can mean absolutely nothing, or it can mean poor cardiac function. It depends on the patient.

S1. “Lub” This is the normal sound of the Mitral and Tricuspid valves closing.

S2. “Dub” This is the normal sound of the Aortic and Pulmonic valves closing.

S3. An abnormal sound heard shortly after S2. It typically indicates delayed ventricular filling. This can indicate heart failure in some patients.

S4. Another abnormal heart sound heard shortly before S1. This sound tends to be more problematic as it indicates significantly delayed ventricular filling. This sound is regular associated with coronary artery disease, aortic stenosis, hypertension, or a heart attack.

***HOWEVER, in athletes, an S4 can be normal as it can indicate very efficient cardiac function or physical changes to the heart structure due to training (known as Athlete’s Heart). It is important to distinguish between this and serious clinical pathology. Athlete’s heart is a particular collage of findings including systolic murmur, S4 gallop sounds, and bradycardia in an asymptomatic and well-trained patient. Up to 1/3 of athletes have various electrical rhythm anomalies, some that occur only during exercise, and this can be completely normal. However, symptoms can be similar to hypertrophic cardiomyopathy so cardiac workup is warranted. Typically only an ECG is needed.***

So what are these sounds telling us? The closing of these valves is in precise timing, only about 0.1 second between S1 and S2. So if we are hearing other sounds, the timing is off. Similar to a car engine, this means bad things are probably coming. Extra sounds indicate electrical anomalies that can be seen on EKGs. So what does normal electrical heart function look like?

The usual path looks like this:

Sinoatrial (SA) Node –> Atrioventricular (AV) Node –> Bundle of His –> Atrioventricular (AV) Bundle –> Purkinje Fibers

But many different things can throw a wrench in to this system. In my post on beta blockers, I talked about atrial fibrillation which is just one of the many rhythm disorders we can see. I’m not going to pretend to know more about the electrical function of the heart than a cardiac nurse, so I’m going to let him give you this really awesome explanation. He also goes in to the easy way to read and interpret EKGs. His description makes this so easy to understand so I highly recommend watching it!


As a rehab clinician who is working in most settings, you don’t have to know ALL the details. What you do need to know is what is normal. That way, when you come across something abnormal, you can identify it and make sure it is addressed by the appropriate person. So, just like I recommend when it comes to lung auscultation, just start listening to everyone’s heart! Patients don’t know the different between listening to their heart and listening to their lungs so just listen to it all while you are there. Get an understanding of the variations on normal and try out different auscultation spots like I mentioned above. Soon, you’ll be identifying abnormal sounds and maybe even saving a life by early detection. You’ve got the skills!

Have you ever heard a crazy set of heart sounds? Or listened to heart sounds on something other than a human? Tell be about it in the comments!

More from the Pulmonary Rehab Toolbox…


HFNO stands for High Flow Nasal Oxygen. This is something that was used frequently in patients who were desaturating quickly with symptoms of COVID-19. It has the ability, through the use of several different devices or setups, to deliver very high concentrations of supplemental oxygen to patients with advanced pulmonary diseases or conditions. In theContinue reading “HFNO”


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Magic In Nursing Team. (2017). EKG/ECG Interpretation (Basic): Easy and Simple!. Retrieved from https://www.youtube.com/watch?v=FThXJUFWUrw

McKelvie, R. (2019). Athlete’s Heart. Merck Manual: Professional Version. Retrieved from https://www.merckmanuals.com/professional/cardiovascular-disorders/sports-and-the-heart/athlete%E2%80%99s-heart on 6/22/20.

Follow @DoctorBthePT on Twitter for regular updates!

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That Beautiful Teaching Moment: ABI

If you’ve ever had a student with you for a clinical rotation, you know the feeling of just hoping for that beautiful teaching moment, the one that just opens up naturally. You look for the moment when you can dig a little deeper in to your student’s reasoning skills and let them flex their therapy muscles a little bit harder than usual. It’s one of those moments where they know the right answer, but you get to back track them through the process that they didn’t even know they went through to get there.

I had a wonderful moment like that when I was seeing a patient for at home for sepsis. He had septic pneumonia (same one I mentioned here) and had been intubated and ventilated for several days. He had a complex medical history including DM2, CAD, PVD, and CKD, among other things, but was really just severely deconditioned due to PICS. He came home using a 4-pt walker and 6 L/min of supplemental oxygen. His prior level of function was fishing and doing yard work daily without a device or oxygen. He had rarely ever been sick in his life, and I had the honor of restoring this man to health.

It only took 8 weeks to bring him back and High-Intensity Interval Training was the key factor in his recovery, along with two daughters who ensured 100% compliance with his home program! It was the perfect set up. My student entered on visit number two. She reviewed my evaluation and knew we were going in to a tough case, but she took it in stride. She took charge of his HIIT program and drove the show. Her progressions were beautiful and we worked together to titrate his supplemental oxygen down over time to the point where he no longer even needed it. But the REALLY beautiful teaching moment was the day he came down with gout.

Why on earth would I say gout was beautiful??? It was really the perfect opportunity to integrate her differential diagnosis skills in a patient case that was flowing all too easily. One day, we showed up and our patient couldn’t walk. He was in pain. These things had never been an issue before. We didn’t have a diagnosis of gout at the time, but having seen it plenty of times before, I had narrowed it down fairly quickly. I asked her to do an evaluation of his affected ankle and she did the usual: ROM, swelling, joint mobility… There were some superficial skin wounds so we couldn’t totally rule out cellulitis and she wanted him to see the doctor, so we scheduled him a visit for the next day and we would return the following day for our usual visit.

We got back in the car and I asked her, “so what was your differential list?” I sat and listened quietly as she gave me her list of diagnoses and reasons for each one, but she hadn’t mentioned gout. I attempted to discuss some of the findings with her in relevance to the patient’s age and comorbidities, but still no gout. We discussed it later that day, still no gout. I asked her to go home keep thinking about her findings.

Photo by Pixabay on Pexels.com

Two days later when we went back, I brought it up on the drive there and asked her if she had changed her mind. She hadn’t come up with anything new and was settled on cellulitis. As we were pulling in to the driveway, I said to her, “it’s gout.” She looked confused and then asked why I thought that. To be completely honest, I should have just said “gestalt” because that was the original reason. But instead, I explained the symptoms in the presence of the patient age and history, and lack of reason for infection (no fever, etc). She nodded and was quietly thinking it over as we walked in to the house.

He had a new prescription for an antibiotic so I was a bit concerned I had been thrown off by an angry cellulitis, but then I asked the patient to tell me about his appointment. He said the doctor told him he couldn’t rule out cellulitis so gave him the antibiotic, but thought it was probably gout. (Phew!)

So, of course, my next step was to ask my student what we could do for our patient to help with his pain and improve his walking while this gout was flaring. Her answer was perfect: ice, elevation, and compression. But wait… what about his medical history? We had just discussed in the car how he had PVD, CAD, and diabetes. I followed her answer with a question, “how do you know it is safe to use compression?” And this is where the teaching moment happened!

I could see in her eyes that she knew where I was going and that not all people can have compression. I could see in her eyes that she even knew the reason I was asking, since we had just talked about his history in the car. But she didn’t know how to know if it was safe. And this, my friends, is where I got to show my student how and why you would perform an ABI. (AND I WAS SO EXCITED!)

ABI stands for Ankle Brachial Index. It is the systolic blood pressure taken at the ankle divided by the systolic blood pressure taken at the brachium. (Ankle over Brachial) An ABI will tell you how well the arteries are able to circulate oxygen and nutrients to the tissues of that lower extremity.

So why would YOU need to do an ABI?

Yes, I said NEED to do. This is for the safety of your patients. You can’t just be throwing compression at everyone who has edema. There is a clinical decision making process that may require further testing before that can be deemed appropriate. Here’s a few reasons to do ABI testing:

  • If you are planning on providing compression to lower extremity of a patient with PVD or PAD (or any risk factors for these conditions -see below)
  • If you suspect serious PVD/PAD and want to quantify it or monitor progression over longer periods of time (per the Cleveland Clinic, ABI is used for this regularly)
  • If your patient is having difficulty healing lower extremity wounds
  • Your patient reports increased pain in the legs with elevation which is relieved with dependent positioning
  • Your patient reports pain in the legs with activity

This particular test requires some special equipment. I was carrying a Doppler at the time because I had been seeing a couple LVAD patients on and off and needed to be prepared so I retrieved it from my trunk and off we went. If you don’t have access to a doppler, you can use a an automated BP cuff if you are absolutely sure it is accurately calibrated. There is evidence to support this, and it actually increases the specificity of testing significantly.

Speaking of clinometric properties:

When using a Doppler: ABI sensitivity is 95% and specificity is 56% for diagnosis of peripheral artery disease (PAD).
When using an automated blood pressure cuff: ABI sensitivity is 97%, and specificity is 89% for diagnosis of peripheral artery disease (PAD).

Nothing like a good high-specificity AND high-sensitivity test for you to add to your tool box!

As I was having the patient rest in supine for a few minutes to ensure measurement accuracy, I was able to explain the objective findings associated with PAD including:

  • Lack of hair growth on the legs
  • Skin that feels cold and/or clammy and may be pale or mottled in appearance
  • PMHx including diabetes, CAD, high blood pressure, high cholesterol (all of which my patient was on medication for), smoking, and increased age
  • Presence of a gangrenous appendage

That last one is a little weird, but I actually did ABI testing on a patient who had a finger that was gangrenous from the DIP distally. It was only one finger, but his ABI was 0.48. His doctor was incredibly grateful for this information and he was scheduled for surgery shortly after, not only to remove the finger, but also to improve his circulation by opening up the vasculature.

How do you do an ABI?

If you can take a blood pressure, you can do an ABI. It does NOT require a special order to be performed. Like I said, you are just taking blood pressures. I’ve taken blood pressure on legs for patients that don’t have arms and I didn’t need an order for that either! However, performing an ABI is a billable service through Medicare, so if you want to get some referrals going for this service, that’s cool, too. (CPT code 93922 (coded twice, once for UEs and once for LEs, typically requires a -59 modifier) and must be in conjunction with a full evaluation or other procedures for reimbursement). (<–DISCLAIMER: I am no coding expert! Please carefully read the descriptions to ensure you are coding properly!)

  1. Have your patient lay supine and rest for 5 minutes, just like you would if you were doing orthostatics.
  2. Take their normal brachial blood pressure and record your number.
  3. Take out your Doppler and find that dorsalis pedis artery (or posterior tibial).
  1. Get the cuff of your patients leg and inflate until you no longer hear the dorsalis pedis, then go up another 20 mmHG just like you should when taking a typical blood pressure.Release the pressure slowly (just like normal) and record your systolic result (the number at which you hear the dorsalis pedis/posterior tibial flow return).
  2. Repeat on the other leg and then arm.
  3. Divide the highest ankle systolic by the highest brachial systolic to get your result (See worksheet)

To make your math even more simple, you can download this worksheet from Project Lead the Way (2014):

Or if that doesn’t work, there is a comprehensive worksheet and instruction set here.

Ok…. so now what?

Well, there are some normative values to which you need to compare your result

  • Normal: 1.0 to 1.3
  • Borderline PAD: 0.9 to 1.0
  • PAD: 0.9 or less
  • Moderate PAD: 0.4 to 0.7
  • Severe PAD: less than 0.4
  • If you get a number greater than 1.3, this indicates the arteries have become rigid. Arterial calcification is typically at fault, thanks to diabetes.

If you are seeing numbers in the severe category, you can anticipate this patient needing some more extensive interventions IF they are medically stable enough to receive them. However, if their vasculature is functioning that poorly, they may not be stable enough. They would also NOT be a candidate for use of compression to treat whatever it is you are looking to treat, as they would be at a significantly increased risk of losing complete blood flow to their extremity. Needless to say, this should mean you are calling the doctor.

It should be mentioned that it is not your role to interpret ABI information. You can and should be assessing this information, but it is the physician’s call about what to do with it, so report it! Just like with orthostatics, this information is very important in the overall clinical and medical picture of the patient, so doctors want to know!

Thankfully, our patient was giving us 1.1 and 1.2 so he was not at risk for adverse events with proper use of compression. We utilized an ACE wrap and his daughter bought him some low level compression stocking which worked beautifully once we showed them how to put them on him. His gout was fleeting, only a few days, and he was back on track in no time.

How often do you treat patient who have PAD? What interventions do they typically benefit most from? Tell me about it in the comments!

I’ll Huff and I’ll Puff… But the Huff Will Be More Effective

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. ButContinue reading “I’ll Huff and I’ll Puff… But the Huff Will Be More Effective”

Vibration & Percussion

If you read my post on airway clearance techniques, you probably saw vibration and percussion down at the bottom of the force progression. Although I have covered several other pieces of the force progression (Active Cycle of Breathing, PEP Devices, etc) in subsequent posts, I haven’t touched on these topics yet because they haven’t beenContinue reading “Vibration & Percussion”

More Than Just A Respiratory Disease: The Tools You Need to Rehab COVID-19

Isn’t COVID-19 just a respiratory disease? If only that was true. We are good at treating respiratory infections. We have lots of drugs for viral, bacterial, parasitic, and fungal infections of the lungs. Most of them work really well! We also have several back-up treatments, inhaled medications, and adjuvant therapies (like rehab!) that make primaryContinue reading “More Than Just A Respiratory Disease: The Tools You Need to Rehab COVID-19”


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Chaudru, S., de Müllenheim, P. Y., Le Faucheur, A., Kaladji, A., Jaquinandi, V., Mahe, G. (2015). Training to Perform Ankle-Brachial Index: Systematic Review and Perspectives to Improve Teaching and Learning. European Journal of Vascular and Endovascular Surgery. 51. 10.1016/j.ejvs.2015.09.005.

Cleveland Clinic. (2019). Ankle Brachial Index. Retrieved from https://my.clevelandclinic.org/health/diagnostics/17840-ankle-brachial-index-abi

Crawford, F., Welch, K., Andras, A., & Chappell, F. M. (2016). Ankle brachial index for the diagnosis of lower limb peripheral arterial disease. The Cochrane database of systematic reviews9(9), CD010680. https://doi.org/10.1002/14651858.CD010680.pub2

Herráiz-Adillo, Á., Cavero-Redondo, I., Álvarez-Bueno, C., Martínez-Vizcaíno, V., Pozuelo-Carrascosa, D. P., & Notario-Pacheco, B. (2017). The accuracy of an oscillometric ankle-brachial index in the diagnosis of lower limb peripheral arterial disease: A systematic review and meta-analysis. International journal of clinical practice71(9), 10.1111/ijcp.12994. https://doi.org/10.1111/ijcp.12994

Jitendra, M. (2020). Medical Coding Guide: Tips for Coding ABIs. American Medical Coding. Retrieve from https://www.americanmedicalcoding.com/tricks-to-code-cpt-code-93923/

National Institutes of Health. (2020) National Heart, Lung, and Blood Institute: Peripheral Artery Disease. Retrieved from https://www.nhlbi.nih.gov/health-topics/peripheral-artery-disease

Project Lead The Way. (2014). Human Body Systems Activity 4.3.5 Student Resource Sheet. Retrieved from https://www.scribd.com/document/349521701/4-3-5-a-sr-abi-worksheet

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Also known as prior level of function in case you aren’t in to abbreviations. How many times have you written that today? This week? This month? How much thought have you given to what PLOF actually looks like for that patient? Isn’t their PLOF why you are seeing them in the first place? Let’s unpack this…

This past year I have been writing, revising, and editing a chapter for a textbook specific to geriatric considerations in rehabilitation. I was working from an old edition and the phrase “prior level of function” kept showing up. Under every heading, we talked about returning a patient to their prior level of function. Proximal humerous fracture? Return to prior level of function. Vertebral compression fracture? Return to prior level of function. Spinal fusion? Return to prior level of function. But why?

I kept thinking, “Why would I want to return a patient to their prior level of function when that level of function is what lead them to this problem in the first place?” So it was time to change. Instead, I wrote about utilizing proper exercise prescription to rehabilitate a patient to a safe and healthy level of function to prevent further onset of acute medical events or progression of chronic ones. So what does a safe and healthy level of function look like? That’s the tricky part.

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Time is the key factor. Setting the time frame of what the “prior level of function” was seems to be an issue of great debate in our profession. The answer to this question isn’t as hard as it seems. When was the patient last not experiencing any medical issues? That would be the prior level of function I would want to target with therapy. I realize that this could have been many years ago, but who is to say that they can’t recover? If they are determined enough and goal-driven, then why not try to get them there?

Why can’t my 85 year old patient with 6 weeks of ICU time for sepsis on 6L of oxygen and a 4pt walker rehab to his prior level of function without oxygen or a device?

Why can’t my patient with a C5 spinal cord injury from cliff diving walk with a cane a year after injury?

Why can’t my patient with COPD return to playing tennis?

Why can’t my patient with a partial knee replacement go back to running 5Ks in 3 weeks?
Why can’t my patient with metastatic lung cancer on high flow oxygen
climb up and down her stairs without desaturating?

If you are listing answers to these questions, like different impairments and limitations, you are really just listing your targets for intervention.

There is plenty of research out there on hip fracture outcomes. Most of this research says that if someone has a fall with a hip fracture, they can really only hope to rehab to one functional level lower than their prior level of function. We need to be thinking about this critically. Is this outcome a limitation of the patient potential? Is this outcome a limitation of the coverage availability? Or is this outcome a limitation of the clinician’s interventions? Maybe this outcome is, itself, creating a limitation on all of these things: the payer’s willingness to pay, the patient’s beliefs in their abilities, and the clinician’s inherent bias toward the patient’s potential. If we can only control what we can control, I’m going to choose to control my role in this scenario.

If a patient has a fall, starts using a walker for a few months, then falls again and ends up with a femoral neck fracture, gets a pinning, goes to rehab, and comes home with a new walker, why do I want her long term goals to be centered around walking safely with the walker? Of course, we have to take in to consideration the healing times frame of boney tissue, but we need to be looking long term. This patient’s prior level of function is not using a walker, it’s whatever their function was before they experienced the decline. And the interventions shouldn’t be only targeting her hip. She got that fracture from a fall so let’s also be working on her balance and gait speed and working toward getting her off the walker!

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That patient with sepsis I mentioned above? He was back to fishing and yard work without oxygen and without a device in 8 weeks. That patient with COPD is back to playing tennis. That patient with the C5 cord injury walks with a cane still today. The patient with lung cancer not only climbed her stairs but also walked outside all the way around her home without desaturating. That patient with a partial knee replacement ran his 5K after 3 weeks (against my advice, and yes, he paid for it but he did it. He eventually recovered and was just fine. I was really doubtful on this one but patients can be very driven toward their goals!).

Don’t be the limiting factor in your patient’s recovery by choosing their prior level of function for them. Many people were on the slow decline prior to that event and haven’t been their normal selves in a while. Let their goals guide your understanding of the prior level of function they really want to return to. We are the ones who have the skills to get them back to the lives they want. Mary McMillan saw the future of physical therapists as the purveyors of hope. After all these years, we have the tools to turn hope into reality.

Was there ever a patient who achieved tremendous goals with you? Tell me your story in the comments!

More Reads…

A Public Service Announcement: The Chain of Infection (and How YOU Can Break It!)

This post is written for one and all. If you are not a rehabilitation or medical professional, please read this post. Even if you are, please read this post. I’m going to address some things that need clarification. You can have all the opinions you would like, but there are some things that are justContinue reading “A Public Service Announcement: The Chain of Infection (and How YOU Can Break It!)”


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PPE is the WORST! (aka Levels of Infection Control)

Did you know that PPE is actually the very last level of infection control??? To be honest, I have to admit that I had NO IDEA. Until COVID-19 became the impetus for my increase in research and writing, I had no idea that people other than healthcare professionals and their governing bodies were making an effort to reduce infection. And, I’m not commenting on everyone washing their hands or our sterilization teams (whom I consider to be in the group of healthcare professionals). I mean there are construction workers, HVAC people, contractors, architects, builders, and entire governing bodies that don’t work in patient care that do 85% of the work of infection control. Let’s call them out!

The infection control process is actually best illustrated as an upside down pyramid. Once you read through it, you will say to yourself, “Well, of course! I knew that!” But you didn’t really think of it until now, did you? There is actually an entire initiative dedicated to Prevention through Design! If you take a look at how this pyramid is constructed, you can see the levels of effectiveness are right alongside the intervention. And guess what? PPE is the LEAST effective method of infection prevention for patients and for healthcare workers. There is a link on the Resources page that will take you to the NIOSH document for infection prevention controls for more details about how some of these things are done.

I’m going to go through each of these steps to explain and give you an example of how this works. I’m going to use the hazard of stairs as my primary example. Obviously not an infection but may of these steps can’t apply to infection, which is why we need so many steps! But, they can all apply to stairs. Then we will go back and talk about infection control.

Elimination. If only it were this easy, right? Let’s just eliminate the hazard and then we don’t have to deal with it anymore. We all know it is never actually that easy. The flu can’t be eliminated so matter what we try. But there are some instances where elimination can work. Eliminate stairs from a hospital and you don’t have to worry about anyone falling down them. Keep everything on one level and no problems from stairs will arise. Obviously this can’t always be done, especially if the building has already been built, and we are trying to reduce the falls down the stairs 10 years later. That’s why there is another step…

Substitution. So instead of stairs, we can have elevators! Of course this isn’t a full substitution because we still have to have stairs in case of power outages, fires, and other emergencies. But if we substitute the major method of traversing floors in a facility to something safer than stairs, we can reduce the hazards that stairs pose. In the therapy world, this isn’t very functional because we know people use stairs at home and in the community. So let’s substitute actual flights of stairs with wooden framed in steps with handle bars on both sides. That will allow patients who need to perform stairs to practice them in a safe environment and reduce the hazard risk.

Engineering Controls. Ok, so let’s go back to the point of the hospital already being built and there are stairs. Can’t get rid of them. No problem. Engineering can come in and add controls. These types of things include hand rails, vertical bars on the turning platforms, gripper tape to the surfaces, yellow striped hazard tape to the edges of the steps, doors to the stairwell, and badge-locks to the doors. All of these things can help prevent the stairs from being as much of a hazard. There are many examples of engineering controls that apply to infection control, too, and we will investigate those later.

Administrative Controls. Policy policy policy. Change the policies, change the hazard risk. If it is policy that no one allows a patient on the stairs without supervision and assistance, odds decrease that the patient will get hurt. You can start to really see by now how these levels becomes less effective as we move down the pyramid.

PPE. For the sake of our stairs example, we are going to call a gait belt PPE. If we are going to use the stairs with someone who is unsafe and be there to provide them support, we can use equipment to decrease the risk of the training we are providing. However, placing the patient actually on the stairs for training is also the behavior that puts them at the highest risk of being injured. But we have to do it, right? So we use the gait belt to give ourselves a hand. It is our personal piece of equipment that helps (a bit) to prevent a hazard.

So how does all of this apply to viruses? Physical hazards are much easier to remove from the situation, but viruses can’t be fully removed. And substituting a different, less dangerous virus isn’t really a better option, nor is it feasible. So we have to come down to environmental controls next. Negative pressure isolation rooms are the most common thing we probably think of when it comes to treating patients who have a contagious condition. They are used for patients who have measles, influenza, and tuberculosis. The negative pressure room keeps all the air breathed in that room away from other rooms. The air is exchanged out individually, not entering the general air supply in the facility.

Speaking of the air supply, again, we are going to get a bit science-y here and talk about some fluid dynamics. Did you know that HVAC systems for hospitals actually have settings that allow for increased or decreased air exchange based on the square footage of the space and the concentration of people in it at any given time? Some can be self-altering based on occupancy, and some are static and have to be manually changed. A recent study was released that measured the air flow necessary to clear certain sized rooms with certain occupancy that would be required to reduce the transmission probability specific to COVID-19. They actually have it measured out how many cubic meters per minute of air they have to move so that no one would have to wait between using the bathroom for the air to be cleared (that’s 10 m3/min or 200 CFM (cubic feet per minute) for a single occupancy bathroom). For shared common spaces, the airflow needs to be 50 m3/min (or 2000 CFM) if the occupancy is fixed. If you are utilizing a public bathroom with several people in and out, the risk of transmission is difficult to control with this tool. Even air circulation patterns alter infection transmission which really comes in to play in oddly shaped spaces. If you are eating in a restaurant tucked away in that romantic corner, you are going to be more likely to transmit and/or receive transmission of infection due to lack of ventilation of aerosolized particles that are delivered to the space via “leaks” from the primary circulation of air in the restaurant.

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While reading this article, I was thinking to myself, “So what is likely the highest risk thing or place right now based on these factors?” And the article didn’t disappoint. A choir practice in Seattle was studied as an epicenter of outbreak. The airflow in the small church was 20 m3/min and the choir had 60 members present for a 2.5 hour practice. The result of this practice was that 87% of the attendees became infected with COVID-19 from a single source. The authors discussed that choir practice significantly increased the rate of aerosolization with singing (this wasn’t the only choir outbreak) and that other activities such as indoor dance practices and working in a call center would be similar in transmission rate even IF hand hygiene and social distancing were utilized properly.

All of this to really demonstrate that Engineering controls can be put in place to prevent or decrease risk of transmission, but they have to be used properly. And if they are not, other measures put in place like hand washing and social distancing (both environmental controls as they try to remove the contagion) have little effect.

Why am I harping on about engineering controls? Why am I becoming concerned about the amount of air my HVAC system can move? This is why. New findings from this study include

  • 1 min of loud speaking generates at least 1,000 virion-containing droplet nuclei that remain airborne for more than 8 min
  • the smallest droplet nuclei effectively remain airborne indefinitely and have half-lives that are dominated by the ventilation rate, at a saliva viral load of 7 × 106 copies per milliliter
  • Some patients have viral titers that exceed the average titer of Wölfel et al by more than two orders of magnitude thereby increasing the number of virions in the emitted droplets to well over 100,000 per minute of speaking.
  • The droplet nuclei observed in this present study and in previous studies are sufficiently small to reach the lower respiratory tract, which is associated with an increased adverse disease outcome

In essence, talking is sufficient to aerosolize COVID-19 particles and these particles remain in the air for at least 8 minutes. Then pair that with this study with these findings:

  • airborne transmission, particularly via nascent aerosols from human atomization, is highly virulent and represents the dominant route for the transmission of this disease [COVID-19]
  • the importance of airborne transmission has not been considered in establishment of mitigation measures by government authorities 
  • And my personal favorite: It is also important to emphasize that sound science should be effectively communicated to policy makers and should constitute the prime foundation in decision-making amid this pandemic.

All three of these studies referenced recommend personal use of face coverings/masks as the only way to effectively reduce viral transmission and their effectiveness if increased with the addition of other controls such as social distancing and hand hygiene. However, these other controls are not effective without the use of face coverings/masks. For how to make a homemade mask that might actually work, check out this post.

So even though PPE is literally the WORST at controlling infectious transmission, and even though it truly is the last line of defense against transmission, it will end up being the best bet we’ve got. We can’t always control the environment we are in. We can’t substitute a different pathogen that is less virulent. We can implement engineering controls in the facilities we utilize, but not in the community or outdoors. We can add administrative controls to reduce the risk of infections. But ultimately, with COVID-19 and other respiratory pathogens like Measles and Tuberculosis, it’s going to come down to the PPE. Especially in the rehab professions, where close contact and use of different speech techniques are regularly utilized across disciplines, we need to be taking precautions, educating ourselves, and keep each other safe.

Do you work in environmental infection control? How has COVID-19 changed your day-to-day? Tell me in the comments!

More Reads…

Open Heart, Open Mind

I’m always learning something new. I called the cardiologist after an evaluation to report some severe orthostatic hypotension and the nurse and I got to talking. She was going back through the patient’s history and looking for why this may be happening. I had just finished assessing the patient in their home and they wereContinue reading “Open Heart, Open Mind”

Blood Pressure Basics

Are you taking the blood pressure and heart rate of EVERY patient you see for a new evaluation? How about for every visit? A recent survey of over 1800 Outpatient PTs showed that although 51% of PTs reported that over half their caseload had risk factors for hypertension and cardiovascular disease, only 14% of themContinue reading “Blood Pressure Basics”


Research is piling in regarding the neurological effects of COVID-19 and the depth of the research is giving us some really concrete information to help guide treatment, screening, and monitoring strategies. The anecdotal evidence is continuing to build quickly so I’ve significantly updated this post to reflect some of the more recent changes and findings.Continue reading “COVID Brain”


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Evans, M. (2020). Avoiding COVID-19: Aerosol guidelines. Massachusetts Institute of Technology: Department of Physics. Published by medRxiv [ahead of print]. Retrieved from https://doi.org/10.1101/2020/05/21/20108894

NIOSH. (2015). Hierarchy of Controls. Retrieved from https://www.cdc.gov/niosh/topics/hierarchy/default.html

Stadnytskyi, V., Bax, C. E., Bax, A., Anfinrud P. (2020). The airborne lifetime of small speech droplets and their potential importance in SARS-CoV-2 transmission. Proceedings of the National Academy of Sciences. 117 (22) 11875-11877; DOI: 10.1073/pnas.2006874117

Zhang, R., Li, Y., Zhang, A. L., Wang, Y., Molina, M. J. (2020). Identifying airborne transmission as the dominant route for the spread of COVID-19. Proceedings of the National Academy of Sciences. 202009637; DOI: 10.1073/pnas.2009637117

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Out with the Old, In with the New (Dynamic Hyperinflation)

I can’t even begin to tell you guys how much I love teaching people about lung function in the presence of disease (read: HUGE NERD). Teaching patients how to correct for dynamic hyperinflation is one of those things that I really love teaching.

If you remember from a few weeks ago, we talked about how to facilitate hyperinflation for those who suffer from restrictive lung diseases like COVID-19, pulmonary fibrosis, or who were recently extubated. But for people with obstructive disease, hyperflation is actually their biggest issue. Airways get obstructed and CO2 gets trapped in the lung. This takes up space and prevents usable oxygen from reaching the alveoli. So, for people with obstructive diseases like COPD, cystic fibrosis, and emphysema, we actually need to decrease and prevent hyperinflation to improve their function.

Dynamic hyperinflation is hyperinflation that keeps building on itself as they takes breaths. The end result is that the usable space for tidal volume becomes less and less and the patient gets short of breath. Take a look at this video a made for you. It’ll help you understand dynamic hyperinflation as well as a few techniques to correct for it! Enjoy!

(Brockway, K., 2020)

Utilizing these techniques before you get started with exercise is important for a couple reasons. You want the patient to have the most lung volume available for tidal exchange which means getting all the trapped CO2 out that you can. Also, you want to give them some time to practice these techniques. It can be very difficult to breathe this way as oxygen demand increases with activity or exercise so practice is important. In addition to practice, your patient will probably need lots of cueing to keep this up as they become more active.

However, if you can start them off on a good tidal volume, improve their V/Q matching at rest and with activity, and rehabilitate them back to even better than where they were before, you are really doing them the service they need. Make sure to keep monitoring their oxygen saturations with training as they may sink as they learn how to change their breathing. They have spent years trying to figure out how to get air in and you will probably be the first one trying to teach them how to get air out!

What are your favorite methods for getting the old air out and the new air in? Tell me about them in the comments!

More from the Pulmonary Rehab Toolbox…

The Counting Talk Test

Time to give you guys another tool. This one is especially important for patients with COVID-19, and it’s not terribly often that we get an objective measure for exertion. I’ve found the counting talk test to be critical in quantifying exertion in my patients with respiratory diagnoses. This measure is phenomenal for taking breathlessness inContinue reading “The Counting Talk Test”


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