Emergency Blood Supply Planning: A Statewide Prospective Audit To Determine the Potential Benefits of Triaging Red Cells during a Critical Shortage.

Careful planning is critical to ensure blood availability during times of reduced supply and/or increased demand, such as infectious pandemic, act of terrorism or natural disaster. Possible strategies include triaging of supply to prioritize support where transfusion cannot be deferred. However, few data concerning urgency of transfusion are available to inform planning. We designed a random sample survey to assess urgency of clinical need, and hence potential utility of triaging red cells (RC) in an emergency through restricting use only to urgent indications, for a regional population of approximately 5 million. An audit based on random sampling of units at point of distribution was used to assess state-wide RC use over time, and capture data in proportion to actual usage over both rural and metropolitan centers. Randomly selected RC units were tagged with a case-report form during production. Tagged units were distributed to hospital laboratories with routine supply. At time of issue for transfusion, the institutional laboratory completed and returned case report forms from the tagged units. Information regarding recipient demographics, indication for transfusion, urgency of supply, and (where issued to support surgery) urgency of surgery were obtained. Following an initial pilot study to refine the model, approximately 1000 tagged RC units (46% group O, 36% A, 13% B, and 4% AB; RhD positive 85% / negative 15%) of a planned 5000 total have been introduced to the state inventory. Three percent of units were not transfused. Major clinical categories of use included hematology (17% of overall use), gastroenterology (11%), orthopedic surgery (9%), non-hematological oncology (6%), gastrointestinal surgery (6%), cardiothoracic surgery (5%), obstetrics/gynecology (5%), urology (3%), trauma (3%) and pediatrics (2%); miscellaneous indications and anemia not otherwise specified constituted 10% and 22% of transfusions respectively. 18% of units were used in acute transfusion episodes (needed within 1h), 43% for urgent indications (1–24h), 33% semi-urgent (24h - 1 week) and 4% non-urgent. Of the 34% units allocated to support perioperative bleeding; only a quarter of procedures were elective. In 15% of cases the urgency of surgery was not stated. Thus, reporting institutions indicated that only 38% transfused units could have been deferred for more than 24h, and only 9% of total RCs were allocated to support potentially deferrable elective surgery. These early results suggest that triaging of RC supply in an acute shortage would only have a very short term impact on actual RC use, as the majority of RC use is already relatively urgent. Additional strategies for emergency blood contingency planning are required to meet priority clinical needs.