Cross-sectional study of peripheral microcirculation in diabetic patients with microangiopathy: influence of pancreatic and kidney transplantation

Diabetic vascular lesions and peripheral autonomic neuropathy are both closely linked to long-term metabolic control of diabetes. Transcutaneous oxygen tension (P tcO2) measurements were made to elucidate whether autonomic neuropathy disturbs the cutaneous microciculatory blood flow, and whether long-term glucose normalization ameliorates such impairment. Twenty-eight type 1 (insulin-dependent) diabetic patients in whom clinically significant macroangiopathy had been excluded by angiography were studied, subdivided into group An=14; before simultaneous pancreas/kidney transplantation (SPKT); mean age 35 years, range 22–51 years; mean duration of diabetes 24 years, (range 15–32) years and group B (n=14; mean 31 months, range 2–101 months, after successful SPKT; mean age 35 years, range 19–56 years; mean duration of diabetes 22 years, range 14–29 years). On addition there was a group (group C) of age-and sex-matched healthy control subjects (n=14; mean age 35 years, range 23–62 years).P tcO2 measurements included basal recordings at 44°C on the leg and the foot, functional recordings at 44°C after arterial occlusion of the limb for 4 min, measurements during breathing 5 l oxygen per minute and finally while standing up (stand up dP 50/dt). All subjects underwent extensive cardiac autonomic testing. In this cross-sectional study the recordings of basal values and of the functional parameters after arterial occlusion and during breathing oxygen did not differ significantly between groups A, B and C. The stand-up dP 50/dt values were not significantly different between groups A and B (0.43±0.02 vs 0.47±0.03 mmHg/s, mean ± SEM); but A+B values were significantly higher than in C (0.22±0.01 mmHg/s;P<0.001). These values were correlated significantly with all parameters of cardiac autonomic neuropathy (r range−0.56 to −0.88;P<0.001). It may be concluded that normalization of blood glucose by pancreatic transplantation is not able to ameliorate peripheral microcirculation, but that measurement of transcutaneous oxygen tension is a possible new technique for quantifying alterations in the venoarteriolar reflex in peripheral diabetic autonomic neuropathy that lead to disturbed peripheral microcirculation in diabetic patients.