Von Willebrand disease in the Dobermann before surgery
2-year-old female Dobermann scheduled for spaying. After the pre-operative blood draw, the jugular puncture bleeds for several minutes. The owner reports prolonged bleeding when the teeth erupted.
| Parameter | Result | Reference |
|---|---|---|
| Platelets | 265,000/µL | 200,000–500,000 |
| PT | 7.1 s | 6.0–8.5 |
| aPTT | 15.2 s | 10.0–16.0 |
| Buccal mucosal bleeding time | 7 min | < 4 |
| Von Willebrand factor antigen | 14 % | 70–180 |
What is the most appropriate pre-operative measure?
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A. Give desmopressin before surgery and have cryoprecipitate or fresh frozen plasma available
Correct. This is type 1 von Willebrand disease (the Dobermann form): desmopressin releases stored factor from the endothelium and may shorten bleeding. Because the response is variable, cryoprecipitate or fresh frozen plasma should be available as a source of von Willebrand factor.
B. Oral vitamin K1 for 3 days before surgery
Vitamin K corrects deficiencies of vitamin K-dependent factors (II, VII, IX, X), which would prolong PT. Here PT is normal and the defect is in primary haemostasis.
C. Transfuse platelet concentrate immediately before surgery
Platelets are normal in number and intrinsic function; what is missing is von Willebrand factor, which adheres them to the subendothelium. Platelets do not supply that factor usefully.
D. Operate without special measures, because PT and aPTT are normal
PT and aPTT assess secondary haemostasis and are usually normal in von Willebrand disease. The prolonged bleeding time and factor at 14% indicate a real risk of surgical haemorrhage.
lightbulb Key takeaway
Buccal mucosal bleeding time explores primary haemostasis: it is prolonged in von Willebrand disease and thrombopathies, but can only be interpreted if the platelet count is adequate. In predisposed breeds such as the Dobermann, a genetic test exists and von Willebrand factor should be measured before elective surgery.
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Updated: October 31, 2026 · Educational content for veterinary professionals. It does not replace current clinical guidelines or the judgement of the attending veterinarian.