title: Geographic variability in potentially discretionary red blood cell transfusions after coronary artery bypass graft surgery.
abstract: OBJECTIVE
  A number of established regional quality improvement collaboratives have partnered to assess and improve care across their regions under the umbrella of the Cardiac Surgery Quality Improvement (IMPROVE) Network. The first effort of the IMPROVE Network has been to assess regional differences in potentially discretionary transfusions (<3 units red blood cells [RBCs]).
  
  
  METHODS
  We examined 11,200 patients undergoing isolated nonemergent coronary artery bypass graft surgery across 56 medical centers in 4 IMPROVE Network regions between January 2008 and June 2012. Each center submitted the most recent 200 patients who received 0, 1, or 2 units of RBC transfusion during the index admission. Patient and disease characteristics, intraoperative practices, and percentage of patients receiving RBC transfusions were collected. Region-specific transfusion rates were calculated after adjusting for pre- and intraoperative factors among region-specific centers.
  
  
  RESULTS
  There were small but significant differences in patient case mix across regions. RBC transfusions of 1 or 2 units occurred among 25.2% of coronary artery bypass graft procedures (2826 out of 11,200). Significant variation in the number of RBC units used existed across regions (no units, 74.8% [min-max, 70.0%-84.1%], 1 unit, 9.7% [min-max, 5.1%-11.8%], 2 units, 15.5% [min-max, 9.1%-18.2%]; P < .001). Variation in overall transfusion rates remained after adjustment (9.1%-31.7%; P < .001).
  
  
  CONCLUSIONS
  Delivery of small volumes of RBC transfusions was common, yet varied across geographic regions. These data suggest that differences in regional practice environments, including transfusion triggers and anemia management, may contribute to variability in RBC transfusion rates.
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Mich. Electronic address: likosky@umich.edu.
authors.forename: Donald S
authors.initials: DS
authors.lastname: Likosky
authors.affiliation: University of Michigan Medical School, Ann Arbor, Mich.
authors.forename: Paul M
authors.initials: PM
authors.lastname: Al-Attar
authors.affiliation: Departments of Medicine and The Dartmouth Institute for Health Care Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Hanover, NH.
authors.forename: David J
authors.initials: DJ
authors.lastname: Malenka
authors.affiliation: Starr-Wood Cardiac Group, Portland, Ore.
authors.forename: Anthony P
authors.initials: AP
authors.lastname: Furnary
authors.affiliation: Swedish Heart and Vascular Institute, Seattle, Wash.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Lehr
authors.affiliation: Division of Cardiac Surgery, Department of Surgery, Henry Ford Hospital, Detroit, Mich.
authors.forename: Gaetano
authors.initials: G
authors.lastname: Paone
authors.affiliation: Department of Cardiac Surgery, University of Michigan, Ann Arbor, Mich.
authors.forename: Mallika
authors.initials: M
authors.lastname: Kommareddi
authors.affiliation: Department of Surgery, Portsmouth Regional Hospital, Portsmouth, NH.
authors.forename: Robert
authors.initials: R
authors.lastname: Helm
authors.affiliation: Medical Data Research Center, Providence Health and Services, Portland, Ore.
authors.forename: Ruyun
authors.initials: R
authors.lastname: Jin
authors.affiliation: Clinical Outcomes Assessment Program, Seattle, Wash.
authors.forename: Charles
authors.initials: C
authors.lastname: Maynard
authors.affiliation: Department of Cardiovascular Surgery, Beaumont Hospital, Troy, Mich.
authors.forename: Eric C
authors.initials: EC
authors.lastname: Hanson
authors.affiliation: Departments of Medicine and The Dartmouth Institute for Health Care Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Hanover, NH.
authors.forename: Elaine M
authors.initials: EM
authors.lastname: Olmstead
authors.affiliation: Departments of Medicine and The Dartmouth Institute for Health Care Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Hanover, NH.
authors.forename: Todd A
authors.initials: TA
authors.lastname: Mackenzie
authors.affiliation: Departments of Medicine and The Dartmouth Institute for Health Care Policy and Clinical Practice, Geisel School of Medicine at Dartmouth, Hanover, NH.
authors.forename: Cathy S
authors.initials: CS
authors.lastname: Ross
authors.affiliation: Department of Biostatistics, University of Michigan, Ann Arbor, Mich.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
mesh_terms: D000368:Aged; D001026:Coronary Artery Bypass / Q000009:adverse effects / Q000639:trends*; D017707:Erythrocyte Transfusion / Q000009:adverse effects / Q000639:trends*; D005260:Female; D054625:Healthcare Disparities / Q000639:trends*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010818:Practice Patterns, Physicians' / Q000639:trends*; D058996:Quality Improvement / Q000639:trends*; D019984:Quality Indicators, Health Care / Q000639:trends*; D012111:Residence Characteristics; D016896:Treatment Outcome; D014481:United States