Comparison of a reflectance sensor and a transmittance sensor for pulse oximetry
Sato, N.; Yasumoto, K.; Hosoyamada, A.
Masui. Japanese Journal of Anesthesiology 43(2): 262-267
1994
ISSN/ISBN: 0021-4892 PMID: 8164335 Document Number: 437284
We have investigated a new optical reflectance sensor for pulse oxymetry in 70 patients under general anesthesia. The reflectance sensor was applied to the forehead, the dorsal manus, the inguinal region, and the anterior crus of the patients. We could obtain a reliable Sp-O-2 value when the reflectance sensor was applied on both forehead and anterior crus. It was difficult to obtain a reliable Sp-O-2 value with the reflectance sensor without using an additional attachment especially for children. We compared the Sp-O-2 value using the reflectance sensor attached to the forehead, with the Sp-O-2 value obtained by the transmittance sensor attached to a finger or an ear lobe, in 7 volunteers who held the breath as long as possible. When we attached the probes on both ear lobe and forehead, the response time was faster, but the maximum changing value was much larger, compared with those on the finger. We could obtain a reliable and stable Sp-O-2 value using the reflectance sensor, when it was placed on the appropriate site as the forehead or the anterior crus.