Abstract
Recently, the degree of desaturation during 6-minute-walk test (6MWT) is considered to have prognostic value in patients with idiopathic pulmonary fibrosis. In this study, we demonstrate a negative effect of motion on SpO2 during the walking, and present a newly developed device that minimizes the negative effect during the test. Subjects and Methods: Ten healthy volunteers (26±11yrs) performed 6MWT in 4 different manners: 1) usual walking, 2) usual walking while trying to minimize the effect of motion on the finger on which the oximeter-probe was placed, 3) usual walking using a newly developed sling with a shock absorber (75g) wrapped around the finger and the probe, and 4) walking on a treadmill at the same speed as the usual 6MWT while the finger and the probe were in a resting position without movement. SpO2 was measured continuously using a Pulsox 300i (Konica-Minolta).
Results: During the usual walking with/without the finger moving, there was severe desaturation of more than 4% from the baseline. However, when walking with the new device or on the treadmill there was only a small change in the SpO2, which was within the accuracy of the oximeter.
Conclusions: SpO2 monitoring during 6MWT does not provide reliable data on desaturation. However, using the new device, more reliable data on desaturation are available.
- © 2012 ERS