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→Buccal Mucosal Bleeding Time (BMBT)
The BMBT is influenced by all the aspects of this phase, including vasoconstriction, platelet adherence and plately aggregation. Although this makes BMBT an effective screening test for the vascular/platelet (primary) phase of haemostasis, it also means it is not purely a test for thrombocytopathia, as it is often considered: BMBT depends on an intact vasospastic response and adequate platelet numbers as well as platelet function<sup>3</sup>. BMBT is a fairly crude test, and has been found to be normal in some patients with a known platelet function disorder and vice versa<sup>3</sup>. The results of this test therefore should be interpreted with some caution.
The BMBT is influenced by all the aspects of this phase, including vasoconstriction, platelet adherence and plately aggregation. Although this makes BMBT an effective screening test for the vascular/platelet (primary) phase of haemostasis, it also means it is not purely a test for thrombocytopathia, as it is often considered: BMBT depends on an intact vasospastic response and adequate platelet numbers as well as platelet function<sup>3</sup>. BMBT is a fairly crude test, and has been found to be normal in some patients with a known platelet function disorder and vice versa<sup>3</sup>. The results of this test therefore should be interpreted with some caution.
==== Protocol ====
* 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
* With the patient 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. (See reference articles for a diagram of this procedure)
* A standard incision is made in the buccal mucosa with the Surgicutt device selecting an area of mucosa without visible blood vessels. Place the device firmly against the buccal
mucosa but do not press. Depress the trigger, commence timing and remove the device approximately one second after triggering
* 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
==== Interpretation ====
The normal time to cessation of bleeding is:
* 1.7 to 3.3 minutes in restrained, unsedated or unanaesthetised dogs
* <4.3 minutes in sedated or anaesthetised dogs
* <3.3 minutes in anaesthetised cats
A prolonged BMBT may be seen in cases of thrombocytopenia, severe azotaemia and von Willebrands disease. Dogs with coagulation defects may have a normal BMBT although prolonged rebleeding after primary haemostasis may be seen.
Protocol and Interpretation References: [[NationWide Laboratories]]
=== Clot retraction ===
=== Clot retraction ===