Hemorheological disorders in patients with type 1 or 2 diabetes mellitus and foot gangrene.

The aim of the present study was to evaluate blood rheological disorders, in particular RBC enhanced aggregation, and compare changes in these parameters in patients with type 1 and 2 diabetes mellitus. For evaluation of RBC aggregability in the present study we applied the "Georgian technique", which was developed and applied for several years in our laboratory. Its advantage is that it is a direct and quantitative method. In all the investigated patients, diabetes mellitus was complicated with the foot gangrenes. The patients were divided into two groups: (a) with type 1 and (b) with type 2 diabetes mellitus. We matched the RBC aggregability indices in both groups of diabetic patients and compared the obtained results with those in the healthy control group. We found that rheological disorders were considerably pronounced. The RBC aggregability index increased by 62 percent (p < 0.001) in type 1 and by 57 percent (p < 0.001) in type 2 diabetic patients as compared to the control group. However, there were insignificant differences of the RBC aggregability changes between the two groups of patients. Therefore we conclude that blood rheological disorders are similar in both types of diabetes mellitus. The disturbed blood fluidity related to the increased RBC aggregability in the microcirculation promotes, in particular, the development of legs gangrene in both types of diabetes mellitus.

Direct beneficial effect of insulin on blood rheological disorders in the microcirculation.

Under both the in vivo and in vitro conditions we investigated the insulin effect on the most significant factor disturbing the blood rheological disorders in the microcirculation, the red blood cell aggregability. The in vivo studies we carried out in the 42 insulin treated diabetic patients (diabetes mellitus type II), as well as conducted the in vitro investigations of the blood both of the diabetic patients (24) and of the healthy people (20) where the insulin was added to the blood ex vivo. The RBC aggregability in blood investigated with the "Georgian technique" was found significantly enhanced, by about 100 per cents in the diabetic patients. Under the in vivo conditions insulin administered intravenously decreased the RBC aggregability almost to the normal level in diabetic patients. In addition, in the in vitro studies we found that the insulin lowered significantly the RBC aggregability when it was significantly enhanced by addition of Dextran-500, as well as in the blood of patients with the ischemic brain infarcts. The decreasing effect on the RBC aggregability was observed even in the healthy control group where the RBC aggregability was in a normal range.

Regional and systemic hemorheological disorders during feet diabetic gangrene.

We investigated the RBC aggregability in the patients with the foot diabetic gangrenes: in the venous blood samples taken from the damaged foot before its amputation, as well as from the cubital vein (the systemic circulation). The RBC aggregability was investigated with the "Georgian technique" that is sensitive and provided us with direct and quantitative data. We found that the RBC aggregability was higher by about 20%, in the blood flowing from the gangrenous tissue than in the systemic circulation. Therefore, the sources of the systemic hemorheological disorders were the primarily damaged tissues. Taking into account that the blood is uninterruptedly flowing and mixing together in the whole circulatory bed we conclude that in the systemic circulation a certain compensatory mechanism provide for a partial normalization of the blood rheological properties, since the RBC aggregability never reaches the level in the blood of the healthy people.