Whole blood collections are manufactured into various blood components, and each component type is intended to meet a particular patient’s clinical need. These include red blood cells to improve oxygen delivery to tissues, platelets to treat bleeding, or plasma to replace proteins. See the Circular of Information for more indications.
In June 1999, Canadian Blood Services introduced leukodepletion filtration as part of the manufacturing process to reduce the number of white blood cells. For apheresis platelet components, white cell content reduction is accomplished by the apheresis collection procedure. See our Circular of Information, Composition and Properties section, for more details.
Canadian Blood Services began using a manufacturing method called buffy coat production method in 2005*. Buffy coat production refers to a method for preparing components from whole blood donation that was developed in Europe more than 25 years ago, and is in widespread use around the world. With the buffy coat production method, whole blood donations are rapidly cooled to room temperature on cooling trays at the collection clinic. Platelets from the whole blood must be manufactured within 24 hours of collection. The whole blood is centrifuged, to create three distinct layers. The red blood cells and plasma are both extracted, leaving the buffy coat layer in the original collection container. The buffy coat contains the platelets, white blood cells, and some red blood cells and plasma. Buffy coats from four donations are then sterile-docked together along with plasma (male donor) from one of the same four donors, and pooled together. This pooled buffy coat is then centrifuged a second time, and the platelet rich plasma is extracted through a leukoreduction filter to produce a pooled platelet concentrate.
The manufacturing process is semi-automated, and uses centrifuges to spin and create the layers, and automated extractors to separate the layers.
The components remain in quarantine until test results are completed and deemed acceptable. When ready, an end label is applied to each blood component, and it is released for issuing to hospitals.
Buffy coat component production was piloted and then rolled out across Canada over a two year period. Edmonton site pilot – 2005, Vancouver site pilot – 2007, and all other sites – January to December 2008.