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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 50x10⁹/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 50x10⁹/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^{2, 3} to make an incision in the buccal mucosa of the upper lip, and the time between making the incision and the cessation of bleeding is measured² 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 prolonged².

To perform the BMBT test, a standardised tool producing a uniform incision is used^{2, 3} to incise the buccal mucosa of the upper lip, and the time between making the incision and the cessation of bleeding is measured². 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 prolonged².

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^{2, 3}, or caused by uraemia. Hereditary defects in platelet function also exist, and von Willebrand's disease is the most common of these.

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 function³. BMBT is also a fairly crude test, and has been found to be

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 function³. BMBT is a fairly crude test, and has been found to be

normal in some patients with a known platelet function disorder and vice versa³. Therefore, the results of this test should be interpreted with some caution.

normal in some patients with a known platelet function disorder and vice versa³. Therefore, the results of this test should be interpreted with some caution.