Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (746 page)

   The method of Ivy as modified by Mielke, using a commercially available template, is the best standardized way to perform BT. A blood pressure cuff on the upper arm is inflated to 40 mm Hg, two small skin incisions are made through the template on the volar surface of the forearm, and cessation of bleeding is counted every 30 seconds.

   BT may be used when better standardized equipment is not available for:

   Workup of patients with the suspected diagnosis of a platelet defect or von Willebrand disease. Note the extreme variability of BT in patients with von Willebrand disease.

   Monitoring hemostatic therapy for patients diagnosed with bleeding associated with von Willebrand disease, a thrombocytopathy, or uremia (creatinine >1.1 mg/L impairs hemostasis).

   Prior to kidney biopsy in patients with uremia.

   Interpretation

   BT is not proven to be of value in the following conditions:

   Patients with liver disease

   Patients prior to general surgery, coronary bypass, or coronary stent insertion

   Patients prior to orthopedic, ear–nose–throat, or neurosurgery

   In the follow-up of patients receiving ASA, NSAIDs, or antiplatelet drugs (clopidogrel, prasugrel)

   Patients with myeloproliferative neoplasms or myelodysplastic syndromes

   BT is contraindicated when platelet counts are <50,000 cells/μL because it may be difficult to arrest bleeding at the incision site and the test may be noncontributory.