Richard Johnston

The ATS/ERS have published standards for most Pulmonary Function tests. These standards include the criteria that are used for assessing test quality. What these standards don’t address howev…

Pulmonary Function testing is almost unique among medical tests in that it requires maximum effort and cooperation from the patient for quality results. The better you are able to communicate with …

One misconception about DLCO results that I’ve heard over and over is that DLCO/VA is DLCO “adjusted” for lung volume and that using it is a way of “normalizing” DLCO for lung volume. This is…

I’ve mentioned previously that the PFT Lab I am associated with recently went through a major hardware and software update. As part of this update we decided to change spirometry predicted eq…

The respiratory system is in part a mechanical pump or bellows. The Maximum Voluntary Ventilation test (MVV, aka Maximum Breathing Capacity, MBC) is intended to measure the maximum ventilation a pa…

This spirometry report came across my desk today.

If you are not already performing supine spirometry you should consider adding it to your arsenal of tests. Other than an exam table no new equipment is needed to perform it and it is a simple tech…

Many years ago I used to think that lung volume measurements were the easy part of PFTs. As time has gone on I’ve seen that getting accurate lung volume measurements is actually more difficul…

Almost all pulmonary function test systems seem to come with a module that can perform a computerized interpretation of PFT results. Their accuracy has been studied occasionally, often by the devel…