Oxygen transport between the lungs and the body depends on numerous complex factors. Ventilation and the alveolar-capillary surface area are of course important but a critical component is hemoglob…
Recently I was trying to explain the effect of altitude on blood oxygenation to somebody with IPF. They had observed that their oxygen saturation was fairly normal at sea level but that they needed…
My lab is in the final stages of a software update that will allow for electronic signing of our reports. This has been a long and slow process partly because the release date of the software got p…
There are at least a half dozen companies that use an ultrasonic flowmeter in their spirometer. The first patent for an ultrasonic flowmeter was made in the 1970’s but it wasn’t until t…
Sooner or later we all get lucky and find ourselves able to replace older equipment. When you have equipment that’s so old it can’t be repaired (either because the manufacturer no longe…
A lab manager recently emailed me and asked my opinion about whether it was okay to use generic mouthpiece filters on their test systems. They had asked the same question of their equipment manufac…
While reviewing a CPET I noticed the patient had a low PETCO2 throughout exercise and an elevated Ve-VCO2 slope. In addition the patient’s minute ventilation was on the high side (75% of pred…
Once again my lab was questioned by a research study’s primary investigator and study coordinator about why our lung volume results came out significantly lower than another lab’s. In o…
Last week I was discussing the use of DL/VA to differentiate between the different causes of gas exchange defects with a physician. DL/VA is DLCO divided by the alveolar volume (VA). It is an often…
Oddly enough, I recently got a couple emails on the same day about the FEF25-75 and ended up corresponding for a while with the authors. FEF25-75 is a subject that somehow manages to keep resurrect…
