Disorders of Hemostasis

Question 1

What are the most common disorders leading to spontaneous bleeding in dogs?

Answer 1

(Immune mediated) thrombocytopenia
DIC
Rodenticide ingestion

Question 2

What are the most common disorders leading to spontaneous bleeding in cats?

Answer 2

Liver disease
FIP
Neoplasia
Retrovirus induced bone marrow disorders

Question 3

What is the importance of fibrinolysis?

Answer 3

Prevents excessive clot formation

Question 4

What is the first part of a smear examination in the bleeding patient?

Answer 4

Low power scanning for platelet clumps

Question 5

What part of the smear is examined with an oil immersion lens?

Answer 5

Monolayer- where 50% of the RBC touch eachother

Question 6

How is a platelet count estimated?

Answer 6

Each platelet represents 12,000-15,000 per micro litre

Question 7

What is the second cage side test for coagulation?

Answer 7

aPTT or OSPT

Question 8

What does a prolonged buccal mucosal bleeding time indicate?

Answer 8

Thrombocytopenia,

or thrombocyte dysfunction from vWB or NSAIDs

Question 9

What is the common cause of primary hemostatic defects?

Answer 9

Thrombocytopenia

Question 10

How are primary hemostatic defects characterised?

Answer 10

Superficial and mucosal bleeding

Bleeding immediately after venepuncture

Question 11

What is the less common cause of primary hemostatic defects?

Answer 11

Platelet dysfunction-

von Willebrand Disease

Question 12

In what breeds is von Willebrand disease common?

Answer 12

Doberman pinscher
German shepherd
Poodle
Golden retriever
Shetland sheepdog

Question 13

When does a dog with vWD bleed and how is it treated?

Answer 13

During or after surgery (not spontaneous)

DDAVP

Question 14

Approach to thrombocytopenia in 4 steps

Answer 14

1️⃣Drug associated until proven otherwise (2-6 days)
2️⃣FeLV/FIV test cats
3️⃣ Bone marrow aspiration (if no response to pred)
4️⃣ Rule out vector borne disease

Question 15

What dogs are commonly affected with IMT?

Answer 15

Cocker spaniels

Old English sheepdogs

Question 16

How is IMT treated and how long before a response is seen?

Answer 16

Prednisolone
GI Protectants
Response within 24-96 hours

Question 17

How does a secondary haemostatic defect present? (4)

Answer 17

Collapse,
exercise intolerance and dyspnoea,
Abdominal distension,
Hemoarthrosis

Question 18

What are the two most common causes of secondary hemostatic defects?

Answer 18

Rodenticide poisoning

Liver disease leading to vit K deficiency

Question 19

What is the cause of a mixed hemostatic defect?

Answer 19

Disseminated Intravascular Coagulation

Question 20

What disorders are associated with DIC in dogs? (6)

Answer 20

Hemangiosarcoma
Sepsis
Pancreatitis
Haemolytic anaemia
GDV
Liver disease

Question 21

What disorders are associated with DIC in cats? (3)

Answer 21

Hepatic lipidosis
Lymphoma
FIP

Question 22

What clinical feature suggests DIC rather than other haemostatic disorder?

Answer 22

Combined primary (mucosal bleeding) and secondary (blood in body cavities) bleeding

Question 23

How is DIC diagnosed?

Answer 23

RBC fragments/schistocytes
Anaemia
Thrombocytopenia
Coag abnormalities

Question 24

What are the 5 interventions required to manage DIC?

Answer 24

Halt coagulation- heparin/blood products
Aggressive fluid therapy
Oxygen 
Correct acid/base balance
Antiarrhythmics