By Garrett S. Booth; The Department of Pathology, Microbiology and Immunology, Vanderbilt University Medical Center; and Bipin N. Savani; The Department of Medicine, Vanderbilt University Medical Center and the Tennessee Valley Veterans Affairs Hospital
As summer arrives in the Northern Hemisphere the US blood supply faces ever increasing challenges. Historically, blood donations dip in the warmer months, with increased travel deferrals and younger donors less frequently available.1 But these troughs are made especially challenging in the SARS-CoV2 pandemic. Several factors have contributed to worsening stocks for the US blood supply: hospitals reopening for elective surgeries, the cancellation of blood drives, and the reduced capacity for blood center collection resulting from implementing social distancing safety guidelines.2
Additional competition for blood donors to contribute to the convalescent plasma inventories to treat both inpatient and outpatient COVID19 patients could further disrupt the overall inventory of blood for transplant patients.
Clinical team members should remain vigilant in their blood use and continue to transfuse only when necessary. Evidence based guidelines for transfusion practices in the stem cell transplant population include recommendations from the AABB to restrict red cell transfusion practice with a hemoglobin threshold of 7 g/dL in a majority of patients.3 Randomized controlled trials in oncology patients comparing liberal versus restricted transfusion strategies have identified that lower hemoglobin thresholds of 7-9 g/dL are no worse than liberal transfusion triggers of 10 g/dL or higher.4 As such, though further investigation may occur, recommendations for a restrictive red cell transfusion strategy in the absence of symptomatic anemia or hemorrhage are advised.
Prophylactic transfusion of platelets should occur at a threshold of 10,000/µL for all hospitalized patients. The TOPPS trial demonstrated reduced bleeding with prophylactic transfusion in patients below this level and similar trial compared prophylactic transfusion at 10,000/µL versus platelet transfusion for symptomatic bleeding among acute myeloid leukemia and autologous stem cell transplant patients.5,6 Research demonstrates no increase in severe bleeds (WHO grade 3 or higher) with only therapeutic transfusion in autologous stem cell transplant patients. As such, and based on our experience, we recommend prophylaxis at 10,000/µl, with an exception that therapeutic platelet transfusion for autologous transplant patients is acceptable.
Joint statements from the AABB, America’s Blood Centers, and the American Red Cross underscore the importance of judicious use of these limited biologic products, as well as encouraging the donation of blood if individuals are willing and able.7
1. Gilcher RO, McCombs S. Seasonal blood shortages can be eliminated. Curr Opin Hematol. 2005;12(6):503‐508.
2. https://www.cdc.gov/coronavirus/2019-ncov/community/organizations/businesses-employers.html [Accessed on 6/10/2020]
3. J.L. Carson, G. Guyatt, N.M. Heddle, B.J. Grossman, C.S. Cohn, M.K. Fung, T. Gernsheimer, J.B. Holcomb, L.J. Kaplan, L.M. Katz, N. Peterson, G. Ramsey, S.V. Rao, J.D. Roback, A. Shander, A.A. Tobian, Clinical Practice Guidelines From the AABB: Red Blood Cell Transfusion Thresholds and Storage, JAMA : the journal of the American Medical Association 316(19) (2016) 2025-2035.
4. L.J. Estcourt, R. Malouf, M. Trivella, D.A. Fergusson, S. Hopewell, M.F. Murphy, Restrictive versus liberal red blood cell transfusion strategies for people with haematological malignancies treated with intensive chemotherapy or radiotherapy, or both, with or without haematopoietic stem cell support, Cochrane Database Syst Rev 1 (2017) CD011305.
5. S.J. Stanworth, L.J. Estcourt, G. Powter, B.C. Kahan, C. Dyer, L. Choo, L. Bakrania, C. Llewelyn, T. Littlewood, R. Soutar, D. Norfolk, A. Copplestone, N. Smith, P. Kerr, G. Jones, K. Raj, D.A. Westerman, J. Szer, N. Jackson, P.G. Bardy, D. Plews, S. Lyons, L. Bielby, E.M. Wood, M.F. Murphy, T. Investigators, A no-prophylaxis PLT-transfusion strategy for hematologic cancers, The New England journal of medicine 368(19) (2013) 1771-80.
6. H. Wandt, K. Schaefer-Eckart, K. Wendelin, B. Pilz, M. Wilhelm, M. Thalheimer, U. Mahlknecht, A. Ho, M. Schaich, M. Kramer, M. Kaufmann, L. Leimer, R. Schwerdtfeger, R. Conradi, G. Dolken, A. Klenner, M. Hanel, R. Herbst, C. Junghanss, G. Ehninger, L. Study Alliance, Therapeutic PLT transfusion versus routine prophylactic transfusion in patients with haematological malignancies: an open-label, multicentre, randomised study, Lancet 380(9850) (2012) 1309-16.
7. https://americasblood.org/news/joint-statement-on-the-blood-supply/ [Accessed on 6/10/2020]