Early postoperative changes in hematological, erythrocyte aggregation and blood coagulation parameters after unilateral implantation of polytetrafluoroethylene vascular graft in the femoral artery of beagle dogs

Abstract

PURPOSE:The failure of small-caliber vascular grafts still means a serious problem. Concerning the early postoperative complications we aimed to investigate the hemostaseological and hemorheological aspects of this issue in a canine model. METHODS:In the Control group only anesthesia was induced. In the Grafted group under general anesthesia a 3.5-cm segment was resected unilaterally from the femoral artery and replaced with a PTFE graft (diameter: 3 mm). On the 1 st -3 rd -5 th -7 th and 14 th postoperative days the skin temperature of both hind limbs was measured, and blood sampling occurred for hematological, hemostaseological and hemorheological tests. RESULTS:The skin temperature of the operated versus intact limbs did not differ. In the Grafted group leukocyte count was elevated by the 1 st postoperative day, while platelet count increased over the entire follow-up period. Fibrinogen concentration rose on the 1 st -5 th days, activated partial thromboplastin time increased on the 3 rd -7 th days. Erythrocyte aggregation was enhanced significantly on the 1 st -5 th days. In specimens taken on the 14 th day, histologically we found matured thrombus narrowing the graft lumen. CONCLUSIONS:Small-caliber PTFE graft implantation into the femoral artery caused significant changes in several hemostaseological and hemorheological parameters. However, better clarifying the factors leading to early thrombosis of these grafts needs further studies.Key words: Vascular Grafting. Graft Occlusion, Vascular. Erythrocyte Aggregation. Blood Coagulation. Models, Animal. Dogs. Early postoperative changes in hematological, erythrocyte aggregation and blood coagulation parameters after unilateral implantation of polytetrafluoroethylene vascular graft in the femoral artery of beagle dogs

Ovariectomy differential influence on some hemostatic markers of mice and rats

“…Our results showed that the most important changes in blood clotting occurred during the nine days after the animals’ surgery. These findings are online with those recently reported by Toth et al [ 50 ] who found early 3–7 days post-surgery changes in hematological parameters of implanted dogs. The critical importance of this first week was associated with both, inflammatory and acute phase reactions associated with increased FIB and progressive increase in platelet counts where the possibility of thrombotic events increases [ 41 , 50 ].…”

Micro-Rheological Changes of Red Blood Cells in the Presence of an Arterio-Venous Fistula or a Loop-Shaped Venous Graft in the Rat

“…The creation of the loop needs more dissection, and two anastomoses are made, which causes bigger blood loss. Since every surgery causes some level of inflammation (acute phase reaction), these together can explain the significant PO1 week changes compared to the other groups, and it is coherent with former studies (McKenzie and Laudicina, 1998;Arias et al, 2009;Toth et al, 2014). The MCV values showed a significant peak at the PO1 week in the loop group.…”

Influence of stent implantation on erythrocyte aggregation in human native coronary arteries and saphenous vein grafts

“…45,46 Long-term exposure to exogenous devices is associated with increased RBC aggregation. 47,48 Here, stent implantation did not induce hemolysis, possi- 53,54 In the present study, the increased RBC aggregation in coronary aspirate was independent of the treated vessel (RCA or SVG-RCA) and therefore of the amount of released particulate debris. The ex vivo supplementation of pure RBCs from healthy volunteers with patient aspirate plasma increases RBC aggregation by the same order of magnitude as the aspirated plasma during stent implantation.…”

“…Thus, neither the location of blood withdrawal nor the different withdrawal techniques and the resulting different shear and tensile stresses during blood sampling (venous blood samples from the cubital vein with a butterfly cannula; arterial blood samples from coronary arteries taken with an aspiration catheter) had impact on the determined RBC aggregation in vitro and under static conditions. Mechanical stress: Implantation of exogenous devices (eg, circulatory support devices, polytetrafluoroethylene grafts) induces mechanical stress on blood cells, resulting in mechanical instability of the RBC membrane and hemolysis . Long‐term exposure to exogenous devices is associated with increased RBC aggregation . Here, stent implantation did not induce hemolysis, possibly because of only short‐term exposure of RBC to the stent. Contrast agent: Physical components, that is, plasma viscosity, influence RBC aggregation .…”