- Last Update On : 2013-11-04
The bleeding time is an outdated screening test that was used to measure platelet function and vascular integrity. Under controlled conditions an incision is made in the skin and the duration of bleeding measured using a modified template device.
The bleeding time is a highly operator–dependent test, plagued by a lack of clinical reproducibility, and affected by numerous technical factors such as location of the incision, pressure applied, operator experience, and patient factors such as age, gender, diet, hematocrit, skin laxity and medications. Over the past decade, abundant evidence has accumulated that the bleeding time is not reliable as a screening test for perioperative bleeding or as a diagnostic test for bleeding disorders (Arch Path Lab Med, 1996;120:353-56; Arch Surg, 1998;133:134-39; Clin Chem 2001; 47: 1204-1211).
In the absence of the bleeding time, the algorithm below is recommended for evaluating a patient’s risk of excessive bleeding. The best pre-procedure screen to predict bleeding is a careful clinical history including family, dental, obstetric, surgical, traumatic injury, transfusion, and drug history. If the history yields no suspicion of a hemostatic problem, further testing is not warranted. If the history is positive, the most common hemostatic disorders can be ruled out by performing screening tests of coagulation (PT and APTT), a platelet count, and ruling out von Willebrand’s disease (Factor VIII, von Willebrand Factor Antigen, Ristocetin Cofactor). If these tests are negative the possibility of a platelet function disorder can be investigated by performing platelet aggregation testing.
* Factor VIII, Von Willebrand Factor Antigen, Ristocetin Cofactor