Design studies for a blood sedimentation chamber based on gravity

Abstract

Platelets are a very important therapeutic option for several diseases and an intra-operative agent supporting and accelerating the wound healing process after surgery.

The separation techniques of blood components like platelets base on the physics of gravity and centrifugal force. In general the separation of individual blood components is done with a specialized centrifuge because it is a very efficient and fast procedure of platelet preparation.

Platelets can either be separated from whole blood or by plateletpheresis. Getting the therapeutic dose from whole blood sedimentation the platelets must be pooled from multiple donations. Therefore from three to ten units of whole blood are required for a therapeutic dose [1]. Plateletpheresis provides at least one full dose from each donation.

This work focuses on testing the efficiency of a non-centrifugal platelet sedimentation system from autologous blood for intraoperative application. Commercially reasons, that mean finding an alternative blood sedimentation solution replacing a centrifugal system, were the decisive factor for this study. Therefore a patented blood sedimentation chamber design [3] for taking leukocyte/platelet-enriched plasma fraction was adopted. Experimental studies for checking the flow field in the blood sedimentation chamber and its dependencies against certain conditions were performed. The volume flow at the inlet of the chamber and the positioning of the chamber were varied. The flow field was visualized with techniques of experimental fluid mechanics. The flow field was analyzed regarding to the phenomena of blood flow characteristics and blood cell formation. The efficiency of the blood sedimentation chamber based on gravity was not proofed.