Influence of blood collection technique on platelet function and coagulation variables in dogs

Objective-To investigate the influence of diameter of the catheter and blood collection technique on platelet function and variables reflecting secondary hemostasis physiologic anticoagulation and fibrinolysis in dogs Animals-6 healthy Beagles Procedures-Blood samples were collected with 20- and 18 gauge venous catheters immediately after catheters were inserted in a peripheral vein through a 14 gauge central venous catheter that had been placed via the Seldinger technique in a jugular vein <30 minutes before sample collection and through a 13 gauge central venous catheter placed via a catheter-through-the-needle technique <30 minutes before sample collection (techniques 1 to 4 respectively) Platelet function was assessed in hirudin-anticoagulated whole blood via an impedance-based aggregometer with collagen (0 8 0 4 0 2 0 1 and 0 05 mu g/mL) as an inductor Kaolin-activated thromboelastography variables were determined in citrated whole blood Prothrombin time activated partial thromboplastin time fibrinogen and fibrin D dimer concentrations and activity of factor VIII antithrombin protein C and protein S were assessed automatically in citrated plasma Results-At 0 05 mu g of collagen/mL the highest median rate of aggregation was observed for collection techniques 2 and 3 with 4 3 (range 2 5 to 6 5) and 3 7 (range 2 8 to 8 3) aggregation units/min however these values were not significantly different from values for the other collection techniques Generally sample collection technique did not have a significant impact on results of coagulation variables investigated Conclusions and Clinical Relevance-Various blood collection techniques can be used to obtain samples for coagulation testing (Am J Vet Res 2011 72 64-72)