What precautions should be taken for a 64-year-old woman with suspected von Willebrand's disease (vWD) and a history of mild diffuse gastrointestinal (GI) bleed, thrombocytopenia, and borderline international normalized ratio (INR), undergoing a colonoscopy without expected biopsies?

Management of Suspected von Willebrand Disease Patient Undergoing Colonoscopy

For a 64-year-old woman with suspected von Willebrand disease (vWD) undergoing colonoscopy for mild diffuse GI bleeding, desmopressin (DDAVP) should be administered 30 minutes prior to the procedure to maintain hemostasis.

Patient Risk Assessment

This patient presents with several risk factors that require careful consideration:

• Suspected vWD (antigen activity ratio of 0.69)
• Mild thrombocytopenia (platelet count 128)
• Borderline INR
• History of mild diffuse GI bleeding
• Age 64 years
• Diagnostic colonoscopy without expected biopsies

Recommended Management Plan

Pre-Procedure Preparation

1. Hemostatic Management:

   • Administer desmopressin (DDAVP) 0.3 μg/kg IV approximately 30 minutes before the procedure 1
   • This will help stimulate the release of von Willebrand factor from endothelial storage sites and improve hemostasis
   • Monitor response with VWF activity levels if possible

2. Laboratory Monitoring:

   • Confirm baseline hemoglobin and hematocrit values
   • Monitor platelet count (currently 128)
   • Check coagulation parameters (PT/INR/aPTT)
   • Consider checking factor VIII level if not already done

During the Procedure

1. Procedural Considerations:

   • Inform the endoscopist about the suspected vWD diagnosis
   • Avoid biopsies if possible as planned 2
   • If unexpected lesions are found requiring biopsy, use cold biopsy techniques rather than hot biopsy to minimize bleeding risk 2
   • Document the depth of insertion in centimeters from the anal verge 2

2. Monitoring:

   • Maintain vigilant observation for any signs of bleeding
   • Have resuscitation equipment readily available

Post-Procedure Management

1. Immediate Post-Procedure:

   • Monitor for signs of bleeding for at least 4-6 hours post-procedure
   • Maintain hemoglobin >7 g/dL (or >9 g/dL if cardiovascular disease is present) 3
   • Consider a second dose of DDAVP if needed (typically not within 24 hours due to tachyphylaxis)

2. Extended Monitoring:

   • Observe for delayed bleeding for 24-48 hours
   • Provide clear instructions about when to seek medical attention if bleeding occurs
   • Schedule follow-up to complete definitive vWD testing

Special Considerations

Anticoagulation Management

• No need to stop anticoagulants prior to diagnostic flexible sigmoidoscopy without planned biopsies 2
• However, given the patient's suspected vWD and borderline INR, temporary interruption of any anticoagulants is prudent

Antibiotic Prophylaxis

• Not routinely recommended for colonoscopy in patients with bleeding disorders 2

Potential Complications and Management

1. Bleeding:

   • If bleeding occurs, consider additional DDAVP (if >24 hours since last dose)
   • For significant bleeding, VWF-containing factor concentrates may be required
   • Tranexamic acid can be used as adjunctive therapy for mucosal bleeding

2. Fluid Balance:

   • Monitor for hyponatremia, especially in elderly patients receiving DDAVP
   • Restrict fluid intake for 24 hours after DDAVP administration

Follow-up Plan

1. Complete definitive testing for vWD diagnosis
2. Schedule follow-up appointment to review colonoscopy findings and bleeding disorder management
3. Consider hematology consultation for long-term management of vWD if diagnosis is confirmed

This approach prioritizes patient safety while allowing for necessary diagnostic evaluation of the GI bleeding. The use of desmopressin provides temporary improvement in hemostasis for patients with mild to moderate vWD during procedures 1, 4.