The BMBT test is a method of assessing primary haemostasis in the dog and utilises the Simplate II Bleeding Time Device.

PROTOCOL

1. Restraint, sedation or anaesthesia may be required depending on the patient. Sedation by the s/c route is recommended due to the possibility of impaired haemostasis.
1. With the dog in lateral recumbency, the upper lip is folded upwards and held in place with a bandage which is tight enough to result in vessel congestion. (Refer to reference articles for a diagram of this procedure).
1. A standard incision is made in the buccal mucosa with the Simplate II device selecting an area of mucosa without visible blood vessels. Remove the device from the blister pack and twist off the white tear-away tab on the side of the device. Place the device firmly against the buccal mucosa but do not press. Depress the yellow trigger, commence timing and remove the device approximately one second after triggering.
1. Blot the flow of blood at 5 second intervals with filter paper, being careful not to touch the edge of the wound, and record the time to cessation of bleeding. The BMBT is the mean bleeding time for the two incisions. If bleeding continues for >20 minutes then the bandage should be removed and timing stopped.

The normal range to cessation of bleeding is 1.7 to 4.2 minutes with a mean of 2.6 minutes. A prolonged BMBT may be seen in cases of thrombocytopenia, severe azotaemia and von Willebrands disease. Dogs with coagulation defects may have normal BMPT's although prolonged rebleeding after primary haemostasis may be seen.

REFERENCES

Jergens, A.E., Turrentine, M.A., Kraus, K.H. and Johnson, G.S. (1987). Buccal mucosal bleeding time of healthy dogs and of dogs in various pathological states, including thrombocytopenia, uremia and von Willebrand's disease. American Journal of Veterinary Research 48 p 1337 - 1342.

Littlewood J.D. (1992). Differential diagnosis of haemorrhagic disorders in dogs. In Practice 14(4)p 172 - 180.