Measurement of oxygen saturation in venous blood by dynamic near infrared spectroscopy

Abstract

A method for the measurement of oxygen saturation in the venous blood, SvO2, based on optical measurements of light absorption in the infrared region is presented. The method consists of applying relatively low external pressure of 25 mm Hg on the forearm, thereby increasing the venous blood volume in the tissue, and comparing the light absorption before and after the external pressure application. SvO2 has been determined from light absorption measurements in two wavelengths, before and after the pressure application, using a formula derived for two adjacent wavelengths. The method has been applied to the hands and fingers of 17 healthy male subjects, using wavelengths of 767 and 811 nm. SaO2, the oxygen saturation for arterial blood, was also obtained from photoplethysmographic measurements in these two wavelengths (pulse oximetry) using the same formula. The mean (+/- SD) value of SaO2 was 94.5% (+/- 3.0). The mean value of SvO2 was 86.2% (+/- 4.1) for the finger and 80.0% (+/- 8.2) for the hand. These SvO2 values are reasonable for the finger and the hand where arterio-venous anastomoses exist. The method enables the measurement of SvO2 in the limbs, a parameter which is related to tissue blood flow and oxygen consumption.

Scanning, non-contact, hybrid broadband diffuse optical spectroscopy and diffuse correlation spectroscopy system

“…This is likely due to the rich presence of arterio-venous anastomoses [83] which help cooling the body by shunting superficial blood directly from the arteries to the veins and thus bypasses the oxygen-extracting capillary network. The oxygen saturation of venous blood in the fingertip has been estimated to be approximately 86% [84], which is similar to the values obtained in this study.…”

Measuring venous oxygenation using the photoplethysmograph waveform

“…By comparing the spectral absorbance at two or more wavelengths before and after the occlusion, it is possible to infer the oxygen saturation of the blood that collects in the venous compartment. This approach has been experimentally demonstrated [5,6]. In Ref.…”

Estimation of Venous oxygenation saturation using the finger Photoplethysmograph (PPG) waveform

“…In most cases, this phenomenon is seen as a source of artifact which interferes with the estimation of arterial oxygen saturation [3], [5]. However, by using the two conditions mentioned above with K In two previous studies [6], [7] the estimation of venous saturation was facilitated by mechanically inducing the pulsatility in the venous blood with the help of a pressure cuff. Even though the results from both studies showed that it was possible to estimate the venous saturation using the pulsatile venous component, the use of an external source (pressure cuff) for the creation of pulsatile venous component could restrict the use of such a technique to few peripheral measurement sites (e.g.…”