What does an inverse I:E Ratio during exercise mean?

Inspiration and expiration usually take different lengths of time, with inspiration almost always being shorter than exhalation. This is due to both to the physiology of breathing and to the pathophysiology of disease processes. During incremental exercise testing there are usually patterns to the way that inspiratory and expiratory times change and these are occasionally … Read more

2017 ERS Methacholine Challenge Standards

After a couple years of waiting for the new methacholine standards to be released “any day now”, they were finally published in this month’s issue of the European Respiratory Journal. The standard is an open access article and can be downloaded by anyone. The length of time taken to develop the standard was acknowledged and … Read more

Measuring respiratory resistance with the APD

Inspiratory and expiratory flow rates are a function of driving pressure (i.e. the pressure difference between the alveoli and the atmosphere) and airway resistance. For this reason it would seem that airway resistance should be one of the most commonly performed pulmonary function tests but instead it is the outcome of airway resistance and driving … Read more

Social Security Disability Evaluations

I was contacted recently by an individual with some questions about the pulmonary function testing needed for a Social Security Disability evaluation. With a small amount of research I was able to answer their questions but this brought up an interesting point and that is that despite the number of patients we see every year … Read more

CPT Codes

About a month or so ago I was corresponding with the manager of a small PFT lab and in response to one of their questions I had mentioned that there were no CPT codes for MIP/MEP. They responded with “what’s a CPT code?” so I guess this means that CPT codes aren’t as well known … Read more