In the present study we are examining the clot formation and clot stability in patients with severe haemophilia A after they receive recombinat factor VIII and after addition of tranexamic acid. Our hypothesis is that addition of tranexamic increases the clot stability. The perpective of the study is to document whether it is relevant to use traneksamic acid in surgery in patients with severe haemophilia A.

In the present study we are examining the clot formation and clot stability in patients with severe haemophilia A after they receive recombinat factor VIII and after addition of tranexamic acid. Our hypothesis is that addition of tranexamic increases the clot stability. The perpective of the study is to document whether it is relevant to use traneksamic acid in surgery in patients with severe haemophilia A.

Inclusion Criteria:

• Severe haemophilia A
• Above 17 years old
• Thrombocyt count above 100 x 109/l within the past two years

Exclusion Criteria:

• Received recombinant factor VIII with in the past 3 days
• Inhibitor against recombinant factor VIII
• HIV-positive
• Ongoing treatment for hepatitis C
• Known kidney disease
• Allergy against Tranexamic acid
• Not able to give informed consent