NONINVASIVE DETERMINATION OF DERMAL HEMOGLOBIN OXYGENATION AND CONCENTRATION IN PATIENTS WITH PERIPHERAL ARTERIAL OCCLUSIVE DISEASE

Background: Oxygen saturation (S-HB) and concentration (C-HB) of derma l hemoglobin are important parameters for the supply of the skin. They may be non-invasively assessed by means of reflection photometry as h emoglobin is predominantly contributing to the skin reflection spectru m. Methods and Results: Dermal reflection spectra fr-om the middle of the forefoot and from the tip of the toe of 20 healthy subjects and 61 patients suffering from peripheral arterial occlusive disease (PAOD) were recorded and compared to transcutaneoys oxygen pressure (tcPO(2)) . S-HB, and tcPO(2) were significantly higher in controls: compared to patients (ankle pressure (AP) > 50 mmHg) SHE in the skin of the foref oot was 63.8 vs. 54.5% (p < 0.05), C-HB was 0.89 vs. 0.62 aU (p < 0.01 ). In the great toe SHE was 92.9 vs. 59.9% (p < 0.001), C-HB was 2.21 vs. 0.92 aU (p < 0.001). Heating the skin of the forefoot to 44 degree s C yields local dermal vascular reserve capacity: S-HB and C-HB incre ased in all healthy subjects (96.4%; 1.44 aU, respectively). SHE decre ased at the forefoot in 14 and at the toe in 18 of 21 patients with AP < 50 mmHg. At the toe decrease was found in 50 of 61 patients (sensit ivity 82%, specificity 100%).Conclusions: Local vascular reserve capac ity of dermal perfusion is reduced inpatients with PAOD, depending on AP. It should be determined preferably in patients with severe PAOD.