Protocol: Cardiac Surgery Transfusion Triggers

Introduction

Red blood cell transfusion in cardiac surgical patients has been strongly associated with increased infection, increased ischemic post-operative events, prolonged hospital stay, increased mortality, and increased hospital costs. CCM and CTA, in partnership with CTS, have a role to play in reducing red cell transfusions.

Principles

1. This document will confine itself to questions about red blood cell transfusions.
2. The goal of the protocol is to identify cardiac surgical patients who will safely undergo care and receive no homologous blood transfusions.
3. The goal of the protocol is to create an evidenced-based uniform practice for red cell transfusion for cardiac surgical patients.
4. Red blood cell transfusion is indicated for patients in hemorrhagic shock.  “Hemorrhagic shock” implies significantly decreased cardiac output (CI < 2.0) and end-organ perfusion (SvO2 < 55) due to documented hemorrhage. This may involve recent and/or ongoing bleeding.
5. In critically ill patients with hemodynamically stable anemia, a transfusion trigger of <7 g/dL is as effective as a transfusion trigger of <10 g/dL, except in patients with acute myocardial infarction or unstable myocardial ischemia.
6. No evidence supports transfusion for anemia alone in the absence of hemorrhagic shock.
7. Variability in transfusion practice in cardiac surgical patients exists despite national consensus guidelines.

Transfusion triggers

1. Transfusion is unlikely to improve oxygen transport when the hemoglobin concentration is greater than 10 g/dL, and is not recommended.
2. With hemoglobin levels below 6 g/dL, red blood cell transfusion is reasonable since this can be life-saving.
3. Transfusion is reasonable in most postoperative patients whose hemoglobin is less than 7 g/dL but no high level evidence supports this recommendation.
4. In the absence of shock, transfusion for hemoglobin < 7 g/dL should be given one unit at a time.
5. In the patient with borderline hemodynamics, dependent upon two or more pressors, with hemoglobin between 7 and 8 g/dL, red blood cell transfusion may be considered (one unit at a time) and consultation between CTS and CCM attendings may be warranted.
6. Transfusion – like other medications – should not be ordered without knowledge and participation of the CCM team. Transfusion for patients whose hemoglobin is <7.0 may occur without consultation between CTS and CCM attendings.  In patients whose hemoglobin exceeds 7.0, consultation between CTS and CCM attendings is expected prior to elective transfusion.

References

1. 2011 Update to The Society of Thoracic Surgeons and the Society of Cardiovascular Anesthesiologists Blood Conservation Clinical Practice Guidelines*. The Society of Thoracic Surgeons Blood Conservation Guideline Task Force: The Society of Cardiovascular Anesthesiologists Special Task Force on Blood Transfusion: The International Consortium for Evidence Based Perfusion: Ann Thorac Surg 2011;91:944–82
2. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Hebert PC, Wells G, Blajchman MA, et al. N Engl J Med 1999: 340:409-417. The CRIT study: anemia and blood transfusions in the critically ill: current clinical practice in the United States. Corwin HL, Gettinger A, Pearl RG, Fink MP, Levy MM, Abraham E, MacIntyre NR, Shabot MM, Duh MS, Shapiro MJ. Crit Care Med. 2004 Jan;32(1):39-52.
3. A survey of blood transfusion practice in UK cardiac surgery units. Moise SF, Higgins MJ, Colquhoun AD Crit Care 2001;% (suppl A):4. Abstract 
4. Clinical practice guideline: Red blood cell transfusion in adult trauma and critical care. Lena M. Napolitano, Stanley Kurek, Fred A. Luchette, Howard L. Corwin, Philip S. Barie, Samuel A. Tisherman, Paul C. Hebert, Gary L. Anderson, Michael R. Bard, MD; William Bromberg, MD; William C. Chiu, MD; Mark D. Cipolle, Keith D. Clancy, Lawrence Diebel, William S. Hoff, K. Michael Hughes, Imtiaz Munshi, Donna Nayduch, Rovinder Sandhu, Jay A. Yelon, Crit Care Med 2009 Vol. 37, No. 12
5. Impact of 24-Hour In-House Intensivists on a Dedicated Cardiac Surgery Intensive Care Unit .K Kumar, R Zarychanski, D D. Bell, R, J Zivot, A H. Menkis, R C. Arora* Cardiovascular Health Research in Manitoba Investigator Group Ann Thorac Surg 2009;88:1153-1161
6. Increased Mortality, Postoperative Morbidity, and Cost After Red Blood Cell Transfusion in Patients Having Cardiac Surgery G. J. Murphy, B.C. Reeves, C. A. Rogers, S. I.A. Rizv, L. Culliford,; G. D. Angelini, Circulation 2007; 116: 2544-2552

This protocol is provided by the Critical Care Team at Emory Healthcare, Atlanta, Georgia.