What are the risks of performing a dilation and curettage (D&C) in a patient with type 2B von Willebrand's disease who experiences a hemorrhage?

Risks of Dilation and Curettage in Type 2B von Willebrand Disease with Hemorrhage

For a patient with type 2B von Willebrand disease experiencing hemorrhage, dilation and curettage (D&C) carries a significantly increased risk of severe bleeding complications and should be managed with VWF-containing factor concentrates rather than desmopressin, as the latter may worsen thrombocytopenia and increase bleeding risk.

Pathophysiology and Specific Risks

Type 2B von Willebrand disease presents unique challenges during surgical procedures like D&C due to:

• Enhanced binding of von Willebrand factor (VWF) to platelet GPIbα receptors 1
• Preferential loss of high molecular weight VWF multimers 1
• Increased platelet clearance leading to thrombocytopenia 1
• Risk of worsening thrombocytopenia during physiologic stress (including surgery) 2, 3

The hemorrhagic risk is particularly elevated because:

• Surgical stress can trigger release of abnormal high molecular weight multimers, causing platelet clumping and removal from circulation 2
• Postoperative thrombocytopenia has been documented in type 2B VWD patients even without preexisting low platelet counts 2
• The combination of qualitative VWF defects and thrombocytopenia creates a "double hit" to hemostasis

Pre-Procedure Management

1. Laboratory assessment:

   • Complete blood count with platelet count
   • Coagulation profile (PT, aPTT)
   • VWF panel including VWF:Ag, VWF:RCo, FVIII:C, and VWF:RCo/VWF:Ag ratio 4
   • Ristocetin-induced platelet aggregation (RIPA) - typically enhanced at low doses in type 2B 4

2. Hemostatic preparation:

   • VWF-containing factor concentrates are the treatment of choice for type 2B VWD 5, 4, 1
   • Target VWF:RCo levels of ≥80-100 IU/dL for major procedures like D&C with active hemorrhage 4
   • Avoid desmopressin (DDAVP) as it may worsen thrombocytopenia in type 2B VWD 4, 3
   • Consider antifibrinolytic therapy (tranexamic acid) at induction of anesthesia 4

3. Blood product availability:

   • Have platelets, cryoprecipitate, and FFP readily available 5, 4
   • Platelet transfusion may be indicated despite adequate platelet count if there is excessive bleeding 5

Intraoperative and Postoperative Management

1. During procedure:

   • Careful surgical technique to minimize trauma
   • Close monitoring of bleeding
   • Administration of additional VWF concentrates as needed

2. Post-procedure monitoring:

   • Regular assessment of platelet count, as postoperative thrombocytopenia may develop 2
   • Monitor for platelet clumping on peripheral blood smear 2
   • Continue VWF replacement therapy until adequate hemostasis is achieved 4, 6
   • Regular assessment of VWF:RCo, VWF:Ag, and FVIII:C levels 4

3. Management of hemorrhage:

   • Prompt administration of additional VWF-containing concentrates
   • Consider cryoprecipitate if VWF concentrates are unavailable 5
   • Platelet transfusion may be necessary, though results can be suboptimal as transfused platelets may be aggregated by the patient's abnormal VWF 1
   • Consider antifibrinolytic agents (tranexamic acid) as adjunctive therapy 4

Special Considerations and Pitfalls

1. Platelet transfusion challenges:

   • Transfused platelets may be aggregated by the patient's abnormal VWF, providing suboptimal results 1
   • Despite this limitation, platelet transfusion may still be necessary with severe bleeding 5

2. Monitoring complications:

   • Watch for signs of thrombocytopenia even in patients with normal baseline platelet counts 2
   • Monitor for excessive bleeding despite seemingly adequate factor replacement

3. Treatment resistance:

   • Some patients may not respond adequately to standard hemostatic treatment 7
   • In cases of refractory bleeding, consider recombinant activated factor VII as a rescue therapy 7

4. Long-term follow-up:

   • Regular hematology follow-up to monitor for delayed bleeding complications 4
   • Assessment of iron status and response to supplementation if significant blood loss occurred 4

By understanding these specific risks and implementing appropriate management strategies, the increased bleeding risk associated with D&C in a patient with type 2B von Willebrand disease experiencing hemorrhage can be mitigated, though not eliminated.