Veterinary Internal Medicine Nursing

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43 | Help, my patient is bleeding! How to care for patients with von Willebrand’s Disease

Laura Jones

Picture this: you’re on the admit shift on a Tuesday morning, and your next patient is a 6-month-old Doberman for routine neutering.

Is there anything you’d be particularly worried about before surgery? Is there anything you’d discuss with the client or any tests you’d speak to your vet about?

Dobermans are a classic breed affected by von Willebrand’s disease, which is a disease that sits somewhere between thrombocytopenia and coagulopathy. If they have it, bleeding is a very real risk.

Thankfully, if we know beforehand, we can implement strategies to manage the patient’s disease and prevent severe haemorrhage. That starts with understanding von Willebrand’s disease and how it works, which is exactly what we’re covering today.

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But before we do that…

Before we dive into the episode, I wanted to quickly remind you that I’m delivering a free, on-demand webinar on October 14th about how to give better care to your patients in less time. The webinar will be sent straight to your email inbox, along with tips, tricks, and support to help you implement this care to your own patients. To watch the session, simply pop your email address in the box below.

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That being said, let’s get back to von Willebrand’s disease, shall we?

So, what is von Willebrand’s disease, and how does it differ from other coagulopathies?

Von Willebrand’s disease (vWD) is technically a platelet function disorder, but it’s caused by the absence of von Willebrand’s factor (VWF), a clotting factor essential in the formation of a platelet plug. 

As a reminder from episode 42, when bleeding occurs, platelets travel to the site of vessel injury and stick together to form a temporary plug. Well, it’s vWF that makes those platelets stick together - no vWF and no platelet plug. The platelets still flock to the site of bleeding, but they can’t really do anything to stop it - so our patient continues to bleed.

VWD is an inherited condition where patients are born with reduced, dysfunctional or absent vWF. There are three types of the disease:

Type I vWD 

This is the most common form of vWD and is characterised by a partial deficiency in vWF, causing a mild-to-moderate bleeding risk.

Types II and III vWD

These forms of vWD are less common but carry higher risks of bleeding. Dogs with type II vWD have low concentrations of abnormally structured vWF, and dogs with type III vWD have a complete absence of vWF.

Which patients get von Willebrand’s disease?

Being an inherited condition, several breeds are predisposed to the disease. The classic one we all think of is Dobermans - they’re at risk of type I vWD, alongside Corgis, Poodles, Bernese Mountain Dogs, Setters and Westies.

German Pointers (both shorthaired and wirehaired) are at risk of type II vWD, and Scottish Terriers and Shetland Sheepdogs are at risk of type III vWD.

And what signs do we see in these patients?

Patients with vWD present with similar signs to thrombocytopenic patients, as we discussed in episode 42. These signs include:

  • Bruising easily

  • Significant bleeding, even from minor wounds

  • Gingival bleeding, even from chewing on toys or after teething

  • Epistaxis

  • Haematuria

  • Vaginal haemorrhage

  • Haematemesis

  • Melena

  • Excessive bleeding after microchip implantation or surgery

If the patient loses significant amounts of blood as a result, they’ll also present with signs of hypovolaemia/anaemia including:

  • Tachycardia or bradycardia

  • Bounding or weak pulses

  • Pale mucous membranes

  • Prolonged capillary refill time

  • Depressed mentation

  • Exercise intolerance

So that’s what von Willebrand’s disease is. How do we diagnose it?

We need to confirm the patient’s von Willebrand’s factor levels, which we’ll do by drawing citrated whole blood and submitting that to the external laboratory.

But before we do that, we need to narrow down our list of differentials since many diseases can cause bleeding in our patients - so we’ll perform tests including:

  • Full haematology and blood smear examination (to assess the degree of anaemia present and look for thrombocytopenia)

  • Coagulation times: activated partial thromboplastin time (aPTT) and prothrombin time (PT) to look for a coagulopathy

  • Buccal mucosal bleeding time (BMBT) which should be prolonged.

The BMBT is a test of primary haemostasis—i.e., the part where the platelet plug forms. While we need enough platelets to form that plug, they also need vWF to stick together properly. If we have insufficient platelets, insufficient vWF, or both, the patient’s BMBT will be prolonged.

And how do we treat von Willebrand’s disease?

VWD is an inherited condition with no cure. The patient’s prognosis depends on the type of vWD and the risk of bleeding associated with it. However, some treatments can be administered before a planned procedure to temporarily increase the amount of vWF available, preventing bleeding. These include desmopressin and certain plasma products.

Desmopressin, or DDAVP, is used to treat diabetes insipidus. However, it also increases vWF levels by freeing up vWF from stores within the body. It is commonly given to vWD patients or blood donors before their donation to increase the amount of vWF in their blood.

Fresh frozen plasma (FFP) and cryoprecipitate contain varying amounts of von Willebrand’s factor. Cryoprecipitate contains more than fresh frozen plasma, though FFP also contains sufficient levels to treat a vWD patient. Frozen or stored plasma, however, does not reliably contain vWF - it needs to be freshly frozen to guarantee appropriate levels of vWF, as this clotting factor is quickly lost as blood products age.

What about if your patient is bleeding?

If your patient is bleeding, control the haemorrhage as much as possible and begin administering appropriate blood products as needed under the direction of your vet. If significant bleeding has occurred, fresh whole blood may be required, or packed RBCs may be given alongside FFP.

And how else do we care for them?

Alongside increasing their vWF levels and providing supportive care, our nursing aims to prevent further bleeding. Careful handling, minimal restraint, and careful venepuncture/sample collection are needed. Jugular venipuncture should be avoided in these patients, opting to use peripheral veins instead for blood samples. IM injections should also be avoided if possible due to the increased risk of bleeding at the injection site.

Certain medications also impact platelet function (such as NSAIDs, certain antibiotics and certain antihistamines), and their use should be minimised in patients with vWD, as they can increase the risk of spontaneous bleeding in these patients.

Lastly, client education is one of the most significant long-term areas where nurses and technicians make a difference to these patients. With some lifestyle adjustments to prevent injury or wounds and careful planning ahead of surgical procedures, these patients can have a completely normal life expectancy, and the veterinary nurse is vital in supporting clients throughout their pet’s life.

So there you have it! My guide to managing patients with von Willebrand’s disease in practice. Though we can’t cure the condition, there’s a lot we can do to minimise its consequences and manage them when they appear. As nurses and technicians, we’re instrumental in that management—from administering transfusions to monitoring, careful handling, and client support, our role in supporting these patients is vast.

Did you enjoy this episode? If so, I’d love to hear what you think. Take a screenshot and tag me on Instagram (@vetinternalmedicinenursing) so I can give you a shout-out and share it with a colleague who’d find it helpful!

Thanks for learning with me this week, and I’ll see you next time!

References and Further Reading