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→Buccal Mucosal Bleeding Time
The buccal mucosal bleeding time is a simple test that gives a rapid assessment of platelet function, providing platelet numbers are normal. If platelet numbers are below 50x10<sup>9</sup>/l, this test should not be performed since the results will be affected by thrombocytopenia, making them unreliable. The small wound inflicted may also not stop bleeding easily.
The buccal mucosal bleeding time is a simple test that gives a rapid assessment of platelet function, providing platelet numbers are normal. If platelet numbers are below 50x10<sup>9</sup>/l, this test should not be performed since the results will be affected by thrombocytopenia, making them unreliable. The small wound inflicted may also not stop bleeding easily.
To perform the BMBT test, a standardised tool producing a uniform incision is used to incise the buccal mucosa of the upper lip<sup>2, 3</sup>, and the time between making the incision and the cessation of bleeding is measured<sup>2</sup>. During the procedure the lip should be kept turned outwards, with excess blood being gently absorbed at a site away from the incision, without disturbing clot formation or applying pressure. Normally, bleeding should stop within 3 minutes, and a BMBT of greater than 5 minutes is considered prolonged<sup>2</sup>.
To perform the BMBT test, a standardised tool producing a uniform incision is used to incise the buccal mucosa of the upper lip<sup>2,3</sup>, and the time between making the incision and the cessation of bleeding is measured<sup>2</sup>. During the procedure the lip should be kept turned outwards, with excess blood being gently absorbed at a site away from the incision, without disturbing clot formation or applying pressure. Normally, bleeding should stop within 3 minutes, and a BMBT of greater than 5 minutes is considered prolonged<sup>2</sup>.
Acquired platelet function abnormalities are often drug induced, for example by non-steroidal anti-inflammatory drugs<sup>2, 3</sup>, or caused by uraemia. Hereditary defects in platelet function also exist, and von Willebrand's disease is the most common of these.
Acquired platelet function abnormalities are often drug induced, for example by non-steroidal anti-inflammatory drugs<sup>2, 3</sup>, or caused by uraemia. Hereditary defects in platelet function also exist, and von Willebrand's disease is the most common of these.