Home » Newsletter » April 2020

April 2020

COVID and the Blood Transfusion Laboratory: Five Frequently-Asked Questions (FAQ)

Authors: Christine Cserti-Gazdewich MD, FRCPC and Jacob Pendergrast BA, BSc (Med), MD University Health Network (UHN)

As with SARS and other coronaviruses, the odds of transfusion transmission are extremely low – modelled to be 1 in 14 million.[1] (Viral load and inoculation routes are chiefly respiratory.) Patients can be reassured that the blood supply remains as safe,[2] and that COVID risks from blood are vanishingly low, whereas natural (droplet-to-face) modes of contagion deserve the most attention.
Two factors threaten the blood supply the most: Donor willingness to donate, and adequate resources (human and material) in the production/supply/dispensation chain. While only 2-3% of adults donate (despite 40-60% being eligible to do so)[3] in ordinary times, fewer may now be available because of COVID-related factors (and additional fear-driven cancellations).[4] The donation rate of those who are well enough to donate must increase substantially for our supply to be maintained. Please spread the message to donate and book at 1-888-2-DONATE. (1-888-236-6283)
Due to shelf limits/storage times, the product at highest and soonest risk are platelets.
The Blood Bank will be reporting shortage phases[5] in Medical Staff Bulletins. These are defined as:

Foreseeable or manifested limits in inventory call for strict patient blood management.[6] This includes, but is not limited to, the following:

  • Preventing the need: investigate and treat drivers of hematologic abnormalities
    • excessive testing (phlebotomy volumes)
    • iron or B12 deficiency correction
    • erythropoiesis-stimulating agents
    • discontinuing drugs inhibiting platelet number or function
    • discontinuing/reducing agents interfering with coagulation
    • tranexamic acid to prevent mucosal bleeding
    • postponement of myelosuppressive treatments (if feasible)
    • postponement of elective procedures with bleeding risk
    • anatomic correction of bleeding pathologies by least invasive means
  • RBC in stable, non-bleeding patients: 1u orders, triggering at Hb <70g/L
  • Platelets: no prophylactic transfusions of underproduction-thrombocytopenia counts of >10, unless bleeding
  • Coagulation: correction of mildly elevated INRs (<1.8) is not indicated before most procedures; non-bleeding patients with cirrhosis or end-stage liver disease rarely require plasma (including pre-procedure)


  1. Webinar: Update on the COVID-19 Coronavirus Outbreak: Blood Collection and Safety Implications. ISBT Education. Michael Busch, Louis M Katz & Hua Shan. https://education.isbtweb.org/isbt/#!*menu=6*browseby=8*sortby=2*media=5*ce_id=1701
  2. For Patient: Canadian Blood Services, “Why you won’t get COVID-19 from a blood transfusion.” https://blood.ca/en/research/our-research-stories/research-education-discovery/why-you-wont-get-COVID-19-from-blood
  3. To et al. The United States’ potential blood donor pool: updating the prevalence of donor-exclusion factors on the pool of potential donors. Transfusion 2020; 60; 206–215.
  4. “Coronavirus causes ‘worrying’ drop in donors for Canadian Blood Services.” https://www.toronto.com/news-story/9907514-coronavirus-causes-worrying-drop-in-donors-for-canadian-blood-services/
  5. University Health Network Policy & Procedure Manual (Clinical): Management of Blood Product Shortages, 3.130.006. http://documents.uhn.ca/sites/uhn/Policies/Clinical/Blood_Transfusion/3.130.006.pdf
  6. ChoosingWisely (Canada-Transfusion Medicine). https://choosingwiselycanada.org/transfusion-medicine/

Canadian Blood Services stresses continuing need for donations during COVID-19 pandemic

As Ontario and the rest of Canada battles COVID-19, it is critical that we maintain healthy supplies of blood and blood products. Cancer patients cannot stop their treatments, and people with blood disorders will still need blood products to lead healthy lives. These are among our most vulnerable populations, and their need continues.
Canadian Blood Services is committed to meeting every need, and to do that, we need your support. If you are healthy and eligible, please donate blood, plasma and platelets in the weeks and months ahead. If you are unable to donate, you can still be part of Canada’s Lifeline by encouraging others to donate. There are many ways to help.
ORBCoN understands the critical function of blood and blood products, and you have an opportunity to make sure that when patients need blood, it’s there. Thank you for being part of Canada’s Lifeline.

Conserving the Supply of Type O Rh Negative Red Cells: What is the Maximum Age of Child-bearing Potential in Ontario Women?

Author: Allison Collins MD FRDPC, ORBCoN
The demand for type O Rh negative (O neg) red cells continually exceeds the supply, resulting in a perpetual state of shortage. While 6-7% of the Canadian population is blood type O neg, a disproportionate 10% of Canadian Blood Services (CBS) blood donors are of this blood type due to active efforts on behalf of CBS to recruit and retain them. Hospitals, however, request that 11.5% of their red cell inventory be type O neg (Dr. K. Webert, CBS Blood Brief June 2018, available at www.blood.ca ). This places a strain on the limited supply of O neg blood in Canada.
Patients requiring transfusion prior to the determination of their ABO and Rh(D) type must receive type O red cells. Because of the high immunogenicity of the Rh(D) antigen, and the potential risk of hemolytic disease of the fetus and newborn, female children and women of “child-bearing potential” should receive type O neg red cells if emergency transfusion is required. Transfusion medicine lists from the Choosing Wisely® and Choosing Wisely Canada campaigns (www.choosingwisely.org and www.choosingwiselycanada.org ), and the National Advisory Committee on Blood and Blood Products (www.nacblood.ca ) recommend that O neg red cells should be reserved for O neg patients, and for women of child-bearing potential with an unknown blood type and requiring emergency red cell transfusion.
The maximum age used to define child-bearing potential varies between hospitals throughout Ontario. The Canadian Institute for Health Information (CIHI) publishes on its website information about the maternal age of Canadian residents, but combines all women aged 40 years and older into one group (www.cihi.ca ). The CIHI was contracted by ORBCoN to provide more granular data for Ontario women aged 40 years and older, and to provide this information for each Ontario Local Health Integration Network (LHIN). The data from fiscal years 2013-14 to 2018-19 show that 99.8% of Ontario women deliver their babies by age 44 years or younger. Data by LHIN are shown in the Table, and are unchanged from the last report. These data have been collected by ORBCoN since 2007, and there is no evidence of a significant upwards trend in maternal age.
Maternal age cut-off required to capture 99.5% of Ontario births 2013-14 to 2018-19

LHIN99.5% maternal age cut-offLHIN99.5% maternal age cut-off
Erie St. Clair43Central44
South West42Central East43
Waterloo Wellington43South East42
Hamilton Niagara Haldimand Brant43Champlain44
Central West43North Simcoe Muskoka43
Mississauga Halton44North East42
Toronto Central45North West42

If your hospital is using a maternal age of more than 45 years to define child-bearing potential, you are encouraged to look at hospital-specific data to see if your hospital differs significantly from the overall LHIN. If so, you may wish to review your policies for the use of type O neg red cells.
Type O neg red cells should be reserved for patients who truly need them. The detailed report, including trend data and a slide deck, is available on the ORBCoN website www.transfusionontario.org under the “Blood Utilization” tab.