[Hemorheological changes at reconstructive operations on the aorta].

Fifteen patients who had undergone aortic reconstructions were examined. Hemorheologic studies were performed at the following stagest initial anesthesia, the end of operation, the early postoperative period, and the 2nd-3rd days after operation. A study was made of blood viscosity at a shift rate 5-300 s(-1), of suspension stability, caisson viscosity (CV), and the yield stress (YS). The back light diffusion intensity was recorded on the erythroaggregometer ADE=5 (Russia) to evaluate the time of linear aggregate formation (T(1)), the time of three-dimensional aggregate formation (T(2)), characteristics of the end size of the aggregates (Ampl), total hydrodynamic strength of the aggregates (Beta), strength index of especially large aggregates (Ia((2,5))). The index of erythrocyte aggregation (IEA) and the index of erythrocyte deformation (IED) were also computed. Initially, the normal blood viscosity values were marked. However, in the early postoperative period, their values returned to the preoperative level. In patients with complications, blood viscosity appreciably rose, exceeding the preoperative parameters. At the end of operation there was a decrease in erythrocyte aggregation, especially due to the TT(1) and Ampl rise, while beta dropped. In the postoperative period, patients without complications demonstrated the growth of erythrocyte aggregation but Ampl of cell aggregation diminished. In the postoperative period, patients with complications showed a considerable intensification of erythrocyte aggregation due to the rise of Ampl, Beta and Ia((2,5)). Toward the end of operation a decrease of plasma viscosity was revealed in the presence of GV rise. In the postoperative period, patients with complications demonstrated the growth of plasma viscosity concurrently with CV lowering. Toward the end of operation the YS increased. However, in patients with the uncomplicated postoperative period, the magnitude of this parameter dropped and reached permissible values in the given patient group whereas in patients with complications, the YS remained significantly high.