Fall/Winter 2019 Diagnostics Bulletin

Fall/Winter 2019 Diagnostics Section Bulletin

Jennie Weltz Horpedahl, BSRT, RRT, RRT-NPS, RPFT, AE-C

Kadlec Regional Medical Center
Richland, WA
Email: jennifer.weltz-horpedahl@kadlec.org

In this issue:

One PFT Lab’s Story of Improvement

Aleksandar Tomas, MS, RPFT, RCEP

The adult pulmonary function lab at Michigan Medicine tests 22,000 patients per year at seven different locations, utilizing 24 testing systems. We have 21 technologists with various backgrounds: respiratory therapists, exercise physiologists, graduates of varied fields, former EMTs, and nurse assistants from the inpatient floors. Our primary role is to support the department of pulmonary and critical care medicine, which is ranked #5 in the country. We have more than 60 pulmonary physicians on our faculty and 15-20 pulmonary fellows.

With ever-increasing compliance pressures, resulting in more rigorous protocol design and documentation of procedures, we, like many other academic medical centers around the country, are challenged to do more with fewer resources. In order to adapt to these new challenges, we have focused on three main areas: Process, People, and Tools Improvement.

Process Improvement

The most dangerous phrase in our language is, “We’ve always done it this way.” — Grace Hopper

Four years ago, we implemented Lean in Daily Work, replete with Huddles and Every Day Lean Ideas (ELIs), to methodically address process improvement. This was a hospital-wide initiative that came at the same time as my promotion to PFT lab supervisor. This practice involves identifying and addressing gaps in workflow in a methodical way. Doing so has led to great improvements to processes within the unit.

Let me illustrate with an example of how this new process helped improve a specific issue that had plagued our lab for a long time. In the past, prior to the Lean in Daily Work implementation, our average PFT turnaround time (testing to interpreted report in the EMR) was well over five days (one “outpatient week”).

The largest bottleneck was at quality control: the supervisor had to review every last one of 80-120 reports performed that day. The implementation of the Lean in Daily Work led to a drastic change in the PFT lab: technologists would become each other’s quality control. As soon as the testing is finished, another technologist checks its quality, even at times when the pace of the clinic is challenging and even when we are short-staffed. Needless to say, everyone was understandably nervous and some were unhappy (“Why do I have to do their job?”). However, once we broke it down to the granular level, it felt doable.

Accompanying these changes in the PFT lab was a buy-in from the pulmonary faculty and fellows, who committed to interpreting results on the same day the report would appear in their queue. The changes allowed us to meet the ATS Recommendation for turnaround time of 48 hours.

But that was not the only benefit. Collectively, we tried something and it worked. In the process, we learned from one another and have engaged in more discussions about the technical components of PFTs. Everyone feels more invested in the story of quality improvement. Although the process isn’t perfect, we have become better at technical problem solving and better at giving and receiving feedback within the group.

CHART showing Median PFT Turnaround Time at Michigan Medicine’s Adult PFT Lab.
Figure 1. Median PFT Turnaround Time at Michigan Medicine’s Adult PFT Lab. “Done to Preliminary” refers to time of test end until a preliminary copy (QC performed, but not interpreted) is available in the EMR. The value listed is in hours. “Done to Interpret” refers to time of test and until the final, interpreted report is available in EMR. The value listed is in days.

People Improvement

“When we are no longer able to change a situation, we are challenged to change ourselves.” — Victor Frankl

People are our most important resource. Caring, technically competent, motivated individuals are a huge advantage for all in the pulmonary department, starting with our patients. Here’s how a few recent changes in our lab have resulted in people improvement, thus positively affecting our workplace:

  • We have implemented the Leader-Leader instead of a typical Leader-Follower approach, using the Turn the Ship Around model by Captain David Marquet.1 As the term suggests, the main idea behind this shift is to bring out leadership ability from every staff member. From the practical, daily operations standpoint, this means a much better speed of execution in all aspects of our mission. No one is waiting for the supervisor to start troubleshooting; by the time I hear about a problem, many steps have already been taken to address it. We don’t have to wait for a biomed team to address an issue unless absolutely necessary. Perhaps more importantly, technologists feel like their ideas and efforts matter. They feel empowered and safe to improvise when presented with unusual circumstances. It is okay if we make a mistake; we will learn from it. (You may be thinking, “Wait Aleksandar! It is okay if we make a mistake with a patient? Isn’t that unsafe? No, we will never compromise the safety of our patients, but we’ll try things we may never have considered in the past, instead of giving up for fear that the test will not be “perfect.”)
  • We send — yes, pay for — staff to go to conferences and workshops. After returning from an event, a technologist presents newly learned information at our own staff meeting (those attending these staff meeting talks qualify for CEUs). But this is only a small portion of the benefit: most technologists feel a renewed sense of inspiration and purpose and are more engaged with our field after attending these events.
  • We pay for technologists to take the NBRC credentialing exam. We buy study materials for the exam, pay for the day on which they take the exam, and reward them for passing. These are low-cost investments that communicate the message that we will strongly support those staff members who are serious about advancing their careers.
  • When hiring, we look for people who can handle the hectic clinic days and technically challenging patients and data sets, while bringing positive energy to the team. We also look for people who embrace change rather than fight it. We have now started asking interview questions that prompt candidates to share their attitudes regarding change in the workplace.
  • We have raised hiring requirements to match the NBRC’s CPFT/RPFT qualification.

Tools Improvement

“If it ain’t broke, you’re not really trying.” — Red Green

Four years ago, our institution, like many others, was tasked with improving and standardizing High Level Disinfection (HLD) processes. For a PFT lab, this can be summarized with a question: “How do we better clean the mouthpieces?”

We asked a different question: “Can we use a product that will eliminate the need for HLD?” We tried several. The trials were fairly straightforward from the technical standpoint. Many of our technologists embraced this opportunity to figure out the best way forward. However, some technologists, especially the more senior ones, were not as receptive, to put it kindly. Yet, we pushed forward.

In the end, we adopted a filter/mouthpiece product that has eliminated the need for HLD. The analogy here is a web page redesign: everyone hates it for two weeks and then nobody remembers what it looked like before.

Several of our sites also have very little storage space due to original equipment configurations. Some testing rooms are converted exam rooms, designed as “modular” spaces rather than dedicated PFT lab rooms. We have looked at every tool we work with to see where improvements can be made:

  • Computer CPUs: can we convert to small, behind-the-screen CPUs?
  • Are the cart and the chair(s) the best possible options for this particular testing area?
  • How do we store filters, mouthpieces, noseclips?
  • Where do we keep and how do we mount pulse oximeters?
  • How often do we order supplies and where is “central” storage for the PFT lab?
  • Are all the tools set in a way that will work in unison?

In conclusion, we have made the decision to methodically address strengths and gaps within our processes, teams, and tools for the benefit of our patients and the fantastic team that cares for them. The point isn’t to always change or to always resist change, but to consistently evaluate — without bias — whether an improvement is needed and whether the projected impact will be worthy of effort.

Acknowledgments: I would like to thank members of our AARC Diagnostic Section Discussion List for their dialogue and ideas, especially Jeff Haynes. I would also like to thank Katrina Hynes for sharing the Mayo PFT lab process of report QC and interpretation.


  1. Marquet DL. Turn the Ship Around! A True Story of Turning Followers into Leaders. New York: Portfolio Penguin, 2012.

The Mannitol Challenge Test

Holly Wilson, RPFT, SSM Health, St. Louis University Hospital, St. Louis, MO

I am not an expert on the mannitol challenge test, because I only performed a limited number of tests before mannitol was withdrawn from the market. But by using a variety of references, I will share what I do know, and leave you with some excellent resources to help guide you through the process when you do decide to add this valuable test to your laboratory’s scope of service.

In 1998 I had the opportunity to work with Dr. Sandra D. Anderson in the Respiratory Investigation Unit at The Royal Prince Alfred Hospital in Sydney, NSW Australia. It was one of the most exciting opportunities of my career. At the time, Sandy and her clinical research team were hard at work developing the mannitol challenge protocol. Although I was not part of this team, the ups and downs of this process were a regular topic over our daily lunch hour.

In 2011 Aridol was manufactured and distributed by Pharmaxis. After Pharmaxis let their FDA approval lapse, they were looking for a partner to license and distribute Aridol in the U.S. Methapharm licensed Aridol, and it was re-approved for U.S. distribution by the FDA in December 2018.

So what is the mannitol challenge and why should we do it?

The purpose of using mannitol

Mannitol (Aridol) is a sugar alcohol supplied as an inhaled powder for the purpose of bronchial provocation. Mannitol provides an indirect stimulus by causing osmotic changes to the cells lining the airway. Mannitol is highly specific for identifying the bronchial hyper-responsiveness that is consistent with asthma. It is considered to be more specific, but less sensitive, than methacholine for asthma.

It has also been shown to have few false-positives. It is important to remember that most stimuli that provoke an attack of asthma in daily life act indirectly.1 Challenges with indirect stimuli, such as mannitol, adenosine, specific allergens, eucapnic hyperpnea, and exercise, act by causing a release of mediators from inflammatory cells (e.g., prostaglandins, leukotrienes, and histamine), and neuropeptides from sensory nerves, which in patients with asthma causes exaggerated airway narrowing and airflow limitation.2

Mannitol vs. exercise test for EIB

Mannitol challenges have been found safe and useful in identifying asthmatic patients who respond to hypertonic saline, eucapnic hyperventilation, and exercise. When comparing mannitol to exercise testing for EIB, there may be an advantage to using mannitol, since it can be difficult to create symptoms associated with vigorous exercise reported by asthmatics in an environmentally controlled lab.

Also, many patients are simply unable to maintain the steady state exercise criteria for ventilation and heart rate due to physical limitations. That has been reported in 99 children referred for possible diagnosis of asthma, with 21 positive to exercise and 29 positive to mannitol with a test agreement of 84%.3.

The sensitivity of mannitol to identify EIB is greater when the test is < 35 minutes to maintain an osmotic gradient in the airways. For optimal use the test should be no longer than 35 minutes to deliver the full 635 mg.4

The process

The mannitol test uses a standard protocol and dry powder device for delivery. The Aridol kit comes with a blister pack of capsules representing five doses (0, 5, 10, 20, and 40 mg) and one single use dry powder inhaler (DPI). The FEV1 is measured 60 seconds after each of nine doses (0, 5, 10, 20, 40, 80, 160, 160, 160 mg). The doses of 80 and 160 are given as multiples of the 40 mg capsule.

While wearing a nose clip, the patient is asked to exhale completely before taking a slow, controlled, deep inspiration, hold the breath for five seconds, then exhale through the mouth before removing the nose clip. The test result is expressed as the provoking dose to induce a 15% fall in FEV1 (PD15). The response to mannitol is dependent on progressively increasing an osmotic gradient. To achieve this the patient needs to inhale each dose as quickly as possible after the last dose.5


The most common complaint is cough. The patient may also experience pharyngeal pain and throat irritation. To alleviate these, Aridol encourages the technologist to offer small sips of water between doses. Our laboratory has also experienced difficulty with static build up around the capsule within the inhaler (fig.1, 2). This prevents the capsule from spinning within the chamber, so no particles are present on inhalation. This improved when we used tweezers to handle the capsule and worked from an anti-static mat.

Mannitol Dry Powder Inhaler 1
Mannitol Dry Powder Inhaler 1
Puncture of the capsule 1
Puncture of the capsule 1

Also, the technologist may feel pressured to hurry through the test, since the response may be dependent on the speed at which the test is completed. Lastly, the deep inhalation may affect the outcome of the test, as cited in the 2017 ERS Technical Standard for methacholine challenge testing.


The response is expressed as the cumulative dose and a provocative dose (PD) causing a 15% reduction in FEV1 (PD15). A positive response may be achieved in two ways: >15% fall in FEV1 from the baseline (using the post 0 mg FEV1 as the baseline), or a 10% or greater incremental fall in FEV1 (between two consecutive mannitol doses). A negative test is when a cumulative dose of 635 mg of mannitol has been administered and the patient’s FEV1 has not fallen by more than 15% from the baseline.1

Mannitol Challenge
mannitol fall fev1 vs cumulative dose
Anderson, Clin Rev Allergy Immunol, 2003

Valuable addition

A relatively easy test to perform, the mannitol challenge could be a valuable addition to any pulmonary function laboratory’s scope of service. It has been shown to have the same sensitivity and specificity as methacholine challenge testing, but because of the high frequency of negative methacholine challenge tests in patients with a clinical diagnosis of asthma, indirect challenges such as mannitol may be indicated to confirm or exclude the diagnosis with certainty.

Should you wish to learn more about the mannitol challenge, Aridol is an excellent resource for education, including contraindications, medications to withhold, and a step by step process to follow. See their Aridol Online Training. In addition, a comprehensive policy describing the mannitol challenge test is available in the ATS Pulmonary Function Laboratory Management and Procedure Manual (3rd Edition, 2016).


  1. Bronchial challenge tests: usefulness, availability and limitations. Breathe. September 2011;Vol 8.
  2. ATS Pulmonary Function Laboratory Management & Procedure Manual, Chapter 13.
  3. Barben J, Kuehni CE, Strippoli MP, Schiller B, Hammer J, Trachsel D; Swiss Paediatric Respiratory Research Group. Mannitol dry powder challenge in comparison with exercise testing in children. Pediatr Pulmonol 2011;46(9):842-848.
  4. Anderson SD, Charlton B, Weiler JM, Nichols S, Spector SL, Pearlman DS; A305 Study Group. Comparison of mannitol and methacholine to predict EIB and a clinical diagnosis of asthma. Respir Res 2009;10:4.
  5. Ruppel’s Manual of Pulmonary Function Testing. Carl D. Mottram. 11th edition.

New Year’s Resolutions for the Pulmonary Function Lab

Jennifer Weltz Horpedahl, BSRT, RRT, RRT-NPS, RPFT, AE-C

As we draw near to the end of 2019, I find myself both reflecting on the past year and looking forward to the year ahead. I am a big fan of New Year’s resolutions because I find that setting goals or making plans to change behaviors helps me step into the new year on the right foot. Being forward thinking and setting resolutions doesn’t just have to be for your personal life. It can be helpful in your professional life as well.

Below are a few resolutions or goals I would like to challenge you and your lab with in 2020.

  1. Review your reference sets. It can be helpful to review the reference sets that are being used in your laboratory. With the addition of the GLI equations in the last few years it may be time to update your reference sets. Look at both your adult and pediatric reference sets — do they still make sense for your population? What’s available from your vendor and what are your options for updating, if needed?
  2. Biologic QC. If your lab is not performing Bio QC there is no time like the present to start. It often doesn’t take very much time to collect these data, and as the Bio QC subject becomes more comfortable performing maneuvers, it takes even less time. Even one-person labs are able to meet this standard. It doesn’t have to be done on you — who works in or near your lab and might be willing to help? There are a number of options available for plotting collected data in a Levey-Jennings chart, making tracking and analysis of the data quick and easy. Not sure where to start? Take a look on the Diagnostic Section Discussion List. There are many threads on the topic and some good recommendations for Levey-Jennings charts.
  3. Get engaged and engage others. The diagnostic community is stronger when we come together to share knowledge and mentor others. Anyone who has ever gotten support from the Diagnostic Section Discussion List or learned something that shaped their clinical practice from a diagnostic related article, bulletin, webinar, or presentation knows firsthand the value of information sharing. We have been so fortunate to have such great leaders in the field helping to guide and educate us, but I know there are others out there with something to share. I challenge you to submit an article to the Bulletin, answer or ask a question on the discussion list, submit a poster to the AARC Congress, or submit a proposal to speak at a conference. There are many people in the diagnostic community to support you and help you succeed. Trust me, I know this firsthand!

Best wishes for a happy and healthy 2020! I hope to see you all at the AARC Congress, or better yet, I hope to hear from you about a future contribution to the Diagnostic Section Bulletin!

Section discussion list: Go to the Diagnostics Section on AARConnect to network with your fellow section members.

Next Bulletin deadline: Spring/Summer Issue. Please contact Jennie Weltz-Horpedahl if you would like to contribute an article. Jennie will be happy to help guide you through the process if you’re a new contributor!