Clinical Disorders of Hemostasis Associated with Abnormal Platelet Function The finding of
a prolonged bleeding time in a patient whose platelet count is normal suggests some
abnormality of platelet function. This situation may be owing either to an inherent platelet
defect (the usual case) or to the deficiency of a plasma factor necessary for some aspect of
platelet function. Tests of platelet aggregation, using the aggregometer, are now widely used
to investigate patients suspected of having platelet disorders. Another test is to filter venous …