Abstract
Impaired platelet function in hemodialysis patients is considered to be a major cause of their bleeding tendency. To evaluate their platelet function, we examined collagen-induced platelet aggregation and platelet adhesiveness to glass beads.
Studies were performed in 7 healthy controls (2 males, 5 females) and 11 hemodialysis patients (2 males, 9 females). None of them were suffering from diabetes mellitus.The optimal concentration of platelets in the PRP and the optimal concentration of collagen needed to evaluate platelet aggregation were determined. The optimal concentration of platelets and collagen were 25×104/mm3 and 5μg/ml respectively.
There was no significant difference in collagen-induced platelet aggregation between healthy controls and hemodialysis patients just before dialysis.After hemodialysis, platelet aggregation was found to be impaired. Platelet adhesiveness was increased from 5.3±4.5% to 15.3±10.9% with dialysis. This rise in platelet adhesiveness might be partially due to the increased RBC concentration during hemodialysis.Pre and post dialysis platelet counts were 15.1±4.2×104/mm3 and 17.1±4.6×104/mm3, respectively, and this change was not statistically significant. Since hemoconcentration occurs during hemodialysis, the platelets seem to be destroyed or adsorbed during hemodialysis.
In conclusion, platelet aggregation induceed with collagen was impaired after dialysis, probably as a result of deterioration caused by passage of the platelets through the pump, filters and dialysis membrane.
