title: Red blood cell use outside the operating theater: a prospective observational study with modeling of potential blood conservation during severe blood shortages.
abstract: BACKGROUND
  National guidance recommends planning for future blood shortages, but few studies have evaluated how reduced demand could be achieved acutely.
  
  
  METHODS
  A trained observer collected data concerning red blood cell (RBC) transfusion events outside the operating theater during 68 hours of blood bank monitoring over 7 weeks. Data were gathered at the patients' bedside from clinical staff and charts. Transfusions were classified according to the presence of bleeding and medical specialty (medical, surgical, other). Hemoglobin (Hb) transfusion triggers, RBCs transfused, and posttransfusion Hb values were collected. Evidence-based scenarios were used to model the potential RBC savings that could be achieved if acute shortages occurred, incorporating ischemic heart disease as a potential decision modifier.
  
  
  RESULTS
  A total of 83 patients received 100 transfusion events, comprising 207 RBC units, during the sampling periods. The relative use of RBC units across specialties was as follows: medical, 74%; surgical, 22%; and other, 4%. For medical and surgical patients, respectively, 31 and 10% of all RBC units were transfused for anemia without evidence of bleeding, and 38 and 12% were transfused for non-life-threatening bleeding. Eight-five percent of all patients who received transfusions had stable vital signs before transfusion. Our model suggested that only 11% of RBCs would be conserved by cancellation of major surgery, whereas 23% to 47% of all RBCs could be conserved by controlling transfusions to medical patients.
  
  
  CONCLUSIONS
  In institutions with patterns of blood use similar to ours, control of transfusions to medical patients is the most effective response to acute blood shortages.
authors.affiliation: The University of Massachusetts, Boston, Massachusetts, USA.
authors.forename: Bridgid G
authors.initials: BG
authors.lastname: Joseph
authors.forename: Catrina
authors.initials: C
authors.lastname: Hendry
authors.forename: Timothy S
authors.initials: TS
authors.lastname: Walsh
mesh_terms: D001793:Blood Preservation; D017707:Erythrocyte Transfusion / Q000706:statistics & numerical data*; D004912:Erythrocytes; D006801:Humans; D011446:Prospective Studies