Blood on board: The development of a prehospital blood transfusion program in a Canadian helicopter emergency medical service.

Objective: Prehospital blood transfusion has been adopted by many civilian helicopter emergency medical services agencies, and early outcomes are positive. The Shock Trauma Air Rescue Society operates six bases in Western Canada and started a blood on board process in 2013 in Regina that has expanded to all bases. Two units of O negative packed red blood cells are carried on every mission.