Transcutaneous Oximetry is Useful in Vascular Pathology If a Cutaneous Reference Map and a Maximal Exercise Test are Used

Abstract

The measurement of partial oxygen pressure in arterial blood by use of transcutaneous pulse oximetry (tcPo2) is a technique relatively new to clinical practice. However, there are notable differences of values both in healthy and arteriopathic subjects, depending on which part of the limb the measurement is carried out. The authors define a cutaneous reference map for oximetric measurements in both healthy and arteriopathic subjects. In a group of 200 healthy subjects and a group of 82 subjects affected by obliterative arteriopathy of the lower limbs at the second Fontaine stage, oximetric measurements were carried out under rest conditions. By comparing the oximetric ranges at all examined levels, it can be seen that there is a wide band of overlap between the minimum values of healthy subjects and those of the arteriopathic subjects. In a group of 30 healthy subjects and in a group of 30 subjects affected by obliterative arteriopathy of the lower limbs at the second Fontaine stage, oximetric measurements were taken at I, II, III back levels of the leg during maximal treadmill test. In this case, by comparing the oximetric ranges between the two groups, it can be seen that all arteriopathic subjects present significantly lower values as compared with those of the healthy subjects at each examined level. This permits a confident diagnosis of pathology. The authors conclude that in order to make a correct diagnosis of arteriopathy by using transcutaneous oximetry, it is necessary to consider both the measurements carried out under rest conditions and those carried out during maximal treadmill test.