Dilutional Coagulopathy in Patients Undergoing Elective Surgery

• Dynamic whole blood clot formation.
  

• A) Single coagulation factor activities B) Platelet function C) Whole blood clot stability. D) Thrombin generation.
  

Background Hydroxyethyl starch (HES) is a group of artificial colloid solutions widely used for plasma expansion and volume resuscitation. HES consist of branched chains of hydroxylated glucose molecules defined by average molecular weight, degree of hydroxyethylation, and C2/C6 ratio. Several clinical reports and in vitro experiments have documented an impaired coagulation system induced by haemodilution with HES and other colloid plasma expanders. The exact mechanisms responsible for HES induced coagulopahty are not fully understood although reduced levels of von Willebrand factor (vWF), acquired platelet dysfunction, reduced factor VIII levels, and dysfunctional fibrinogen polymerization seems to reflect an important aspect of the pathogenesis.

Experimental laboratory studies performed in our centre and verified by several other research groups have shown successful reversal of the colloid plasma expander induced coagulopathy by fibrinogen concentrate.10-13 So far, the present knowledge are based on laboratory experiments and animal studies. Hence, it appears desirable to perform a comprehensive description of haemostasis parameters following HES induced dilutional coagulopathy in an acute clinical bleeding situation.

Materials and Methods

Study design: Clinical, prospective, double-blind, randomised, place-controlled trial. Blood samples:

Primary end point:

Dynamic whole blood clot formation

Secondary end points:

A) Single coagulation factor activities B) Platelet function C) Whole blood clot stability. D) Thrombin generation

Perspectives:

Serious surgical and traumatic bleedings are common and associated with a high mortality rate. The present study can significantly contribute to our overall understanding of the mechanisms involved in HES induced dilutional coagulopathy.