UMEM Educational Pearls

•Hemophilia A is the deficiency of factor VIII, hemophilia B, the deficiency of factor IX.  In this disease, thrombin is not formed by VIIIa or Ixa
•Emergent presentations are due to bleeding. Hemophiliac joints have a higher tendency to bleed, because synovial cells make more tissue factor pathway inhibitor, and so have higher Xa inhibition.
•Especially in severe hemophilia, alloantibodies can develop that neutralize factor VIII.  Presence of an inhibitor may mean decreased responsiveness to treatment with factor concentrate.  Factor VIII in high doses may overcome this.
Labs:
•Hemoglobin, hematocrit, platelets, PT, INR are likely to be normal.  PTT may be normal or prolonged, it is more likely prolonged in severe disease. Draw 2 extra blue-top tubes to be spun and frozen for inhibitor assays.
Management:
•Several studies have shown the safety and efficacy of NSAIDs for pain control for arthritis in hemophiliacs.  However, these studies tend to be small and in select groups of hemophiliacs, under careful supervision.
•DDAVP can be useful in mild hemophilia.  FFP and cryoprecipitate are not used, due to concerns for volume overload and viral transmission.  Recombinant FVIII concentrates are the treatment of choice.  1U/kg will increase plasma levels by 2%.   The severity of the bleeding dictate the goal serum percentage (30-100%) and the time (hours –days) it should be kept at this level.  
•Consult the blood bank and hematology early, for optimal management.