Transcutaneous oxygen pressure in systemic sclerosis: evaluation at different sensor temperatures and relationship to skin perfusion.

Transcutaneous oxygen pressure (TcPO2) and skin blood flow (as evaluated by laser doppler) (LD) were investigated in 24 systemic sclerosis (SSc) patients in sclerotic skin (dorsal aspect of the hand) and non-sclerotic skin (interscapular region) and in 24 controls matched for sex and age for the same sites. The two parameters were evaluated at 44 degrees C (temperature of the two sensors) in 13 patients and 13 controls, and at 36-37 degrees C in the remaining 11. At 44 degrees C, TcPO2 was lower in SSc patients than in controls for both sclerotic and non-sclerotic skin. At 37 degrees C there was no significant difference. At 44 degrees C, LD values were decreased in patients with respect to controls for both sclerotic and and non-sclerotic skin. In contrast, at 37 degrees C the values were increased in patients only for the sclerotic skin. It can be hypothesized that the increased LD values at physiological temperature are at least in part balancing a decreased tissue oxygen tension, then a normal TcPO2 is ensured. On the other hand, the decreased LD values at 44 degrees C, when TcPO2 is also decreased, indicates that there is an inability of SSc vessels to significantly increase their flow under the stimulus of a maximal hyperaemia-inducing temperature.

Photo-reflex-rheographical method in the evaluation of elastocompression.

The importance of a "compression-mobilization" association in order to attain a correct therapeutical procedure is stressed. The authors then report the results of a study conducted on patients affected by varices to establish the efficacy of a treatment by means of elastic stockings with graduated compressive pressure and the efficacy of reflex-rheography as a noninvasive, economical and easy-to-use method for the assessment of the variations in venous return flow produced by the association of muscular activity and elastocompression.

Effects of Centella asiatica extract on mucopolysaccharide metabolism in subjects with varicose veins.

The effects were studied of the total triterpenic fraction of Centella asiatica on serum levels of the uronic acids and lysosomal enzymes involved in mucopolysaccharide metabolism (beta-glycuronidase, beta-N-acetylglucosaminidase, arylsulfatase) in patients with varicose veins. The basal levels of uronic acids (467.7 +/- 69.3 micrograms/ml) and of lysosomal enzymes (beta-glycuronidase 1.8 +/- 0.4 microM/min/l, beta-N-acetylglucosaminidase 23.1 +/- 0.4 microM/min/l, arysulfatase 0.078 +/- 0.003 microM/min/l) were elevated, indicating an increased mucopolysaccharide turnover in subjects with varicose veins. During treatment with Centella asiatica extract (60 mg/day for three months), these levels fell progressively. At the end of treatment the serum uronic acid (231.8 +/- 51.5 micrograms/ml), beta-glycuronidase (1.2 +/- 0.05 microM/min/l), beta-N-acetylglucosaminidase (17.7 +/- 0.7 microM/min/l) and arysulfatase (0.042 +/- 0.003 microM/min/l) levels were highly significantly lower than the basal levels (p less than 0.01). The results of this trial provide an indirect confirmation of regulatory effects of the extract of Centella asiatica on metabolism in the connective tissue of the vascular wall.

A new method for the quantitative assessment of arterial insufficiency of the limbs: cutaneous postischemic hyperemia test by laser Doppler.

The cutaneous postischemic hyperemia test, by means of laser Doppler flowmetry, was carried out on 71 normal, healthy lower extremities and 138 lower limbs suffering from peripheral occlusive arterial disease. The test, a new technique for evaluating the hemodynamics of limbs, permitted a clear distinction between normal, healthy subjects and patients suffering from arterial disorders. It was also seen that the degree of deterioration in the quantitative parameters was quite obviously related to the seriousness of the clinical picture. A comparison of the more severely and less severely affected limbs of each patient and the values taken bilaterally gave a correspondence of 98.6%. A therapeutic cycle consisting of the intraarterial administration of naftidrofuryl in 20 limbs achieved a statistically significant improvement in two parameters (tL and tR). Four limbs were treated with percutaneous transluminal angioplasty. After treatment the values obtained with the test were found to be absolutely normal. It is therefore suggested that this test be widely adopted in vascular diagnostic laboratories.

Evaluation of the effects of vasoactive drugs on cutaneous microcirculation by laser Doppler velocimetry.

The effects provoked in different points of skin circulation by a vasoactive drug injected in the femoral artery of patients affected by chronic obliterative arterial disease at clinical stage 2, were evaluated using the laser Doppler velocimeter. At the same time, by means of strain gauge plethysmography, measurements were taken of the relative variations of volume and amplitude of the pulse waves in the hallux and of blood flow in the calf. After administration of the drug, a number of phenomena were observed, the most notable of which was a rapid and intense shift of blood from skin to muscle, followed by an increase in the global perfusion of the limb. Considering the physio-pathological importance of regional blood redistribution between skin and muscle and the high frequency rate of skin lesions in vascular diseases of the limbs, the possibility of evaluating, with a practical, non-invasive technique, the effects of drugs at the skin level is of great interest.