To the Editor,
Due to the COVID‐19 pandemic that has led to the shortage of group O‐packed red blood cells (RBCs), hospitals and transfusion services are inventing ways to conserve and use less RBC products. Association for the Advancement of Blood & Biotherapies (AABB), America's Blood Centers, and the American Red Cross have all issued a joint statement informing the public of the critical status of the national blood supply and urging all eligible people to consider blood donation.
Similar to other industries, the blood community is experiencing workforce challenges, there‐by leading to a significantly reduced number of trained staff available to collect, test, manufacture, and transport blood products. In order to prepare for anticipated blood supply issues, AABB's recommendation to all hospital transfusion services includes developing strategies that address the risk for shortages, continuously assessing blood inventory and utilization needs, and informing physicians and providers ordering blood transfusion about critical blood supply issues.
Generally, whole blood should be collected into an anticoagulant volume calculated for 450 ± 45 ml or 500 ± 50 ml. According to the technical manual, 1 RBCs that are labeled as low volume units contains 300–404 ml when the whole blood is collected into 450 ± 45 ml bag or 333–449 ml when the whole blood is collected into 500 ± 50 ml bag. Other components such as platelets, plasma, and cryoprecipitate should not be manufactured from low volume whole blood units.
Previous studies have already demonstrated the quality of under collected blood for transfusion. 2 , 3 These low volume RBC units are acceptable for transfusion, therefore, availability of these units would make an additional important contribution to the already depleted blood supply without involving additional expense. In many cases, these low volume units are discarded; however, utilization of these precious resources would be an important addition to the nation's blood supply.
We have been recently receiving these low volume RBC in additive solution (AS‐3) units collected in 450 ± 45 ml bag from our blood supplier and have transfused 30 units to actively hemorrhaging trauma patients who need an emergency blood transfusion. We have also performed the hematocrit on 11 of the units with average unit hematocrit of 59.6%, range of (50.6%–67.7%). The average volume of each unit is 255 ml with a range of (237–278 ml). According to Davey et al. 4 the higher concentration of dextrose and adenine in low volume RBC units collected in citrate phosphate dextrose adenine‐1 (CPDA‐1) units may improve posttransfusion red cell viability and subsequently posttransfusion RBC survival. This is similar to the concentration of dextrose and adenine in units collected with additive solutions.
The RBC low volume units have a collection volume of between 66% and 90% of a normal blood unit. It is expected that the dose of hemoglobin, if lower, would not fall below 66% of a standard RBC unit. According to the Circular of Information prepared jointly by the AABB, the American Red Cross, America's Blood Centers, and the Armed Services Blood program, RBCs, Low Volume “may not be an indication of a lower dose of hemoglobin.”
We are a level one trauma center and our main concerns were group O unit availability to support our trauma program. The use of these low volume units was initiated with careful consideration from members of our blood conservation and utilization team (transfusion medicine committee) when evaluating ways to meet the needs of our trauma program and protect the blood supply. These low volume units cost us 10% less than our standard unit cost. There are no regulatory codes or Food and Drug Administration (FDA) variance required prior to transfusing low volume units. There is also no regulatory reason on how you use these products because they are already licensed products. The patient's physician does not need to be notified and Institutional Review Board (IRB) approval is not needed to transfuse these units. These units have International Society of Blood Transfusion (ISBT) code E5242.
Based on our recent practice of transfusing low volume RBC, we are able to enhance our group O RBC inventory and make available these low volume RBCs to patients in need of emergency transfusions. Although we do not know the proportion of low volume RBC units discarded per month, we believe that the destruction of these units is an unnecessary waste of a precious resource. Consideration should be given to make these units more broadly available for transfusion. In extreme times of nationwide blood shortages, low volume RBC units may be an important addition to the nation's blood supply.
CONFLICT OF INTEREST
The authors have disclosed no conflicts of interest.
REFERENCES
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