RIPA (Ristocetin Induced Platelet Aggregation)

Indications Further differentiate Type 2 VWD, specifically to confirm Type 2B VWD
Method platelet aggregation 
Test Information Platelets are agglutinated in vitro by adding  3 concentrations (1.5, 1.0 or 0.5 mg/mL) of ristocetin to platelet rich plasma which is stirred continually. The process is measured spectrophotometrically and the rate and degree of aggregation (clearing of the turbid solution) is plotted by a recorder. 
Sample Requirements Appointment required.  It will be drawn at Bloodworks Northwest.  Call Hemostasis Lab at 206-689-6594 to schedule an appointment
Requisition Form RFT- Hemostasis Reference Laboratory
Transaction Code 3240-04
CPT Codes 85576 x3
Test Schedule Monday - Friday
Turn around Time (analytic time) Same day as scheduled visit
Report/ Results Fax number required to receive report