2021 Clinical Practice Guidelines for Anesthesiologists on Patient Blood Management in Cardiac Surgery

THE COLLABORATION of the Society of Thoracic Surgeons (STS), Society of Cardiovascular Anesthesiologists (SCA), the American Society of ExtraCorporeal Technology (AmSECT), and the Society for the Advancement of Patient Blood Management (SABM) produced the updated 2021 Clinical Practice Guidelines on Patient Blood Management in Cardiac Surgery in the September 2021 issue of JCVA.1Tibi P McClure RS Huang J et al.STS/SCA/AmSECT/SABM Update to the Clinical Practice Guidelines on Patient Blood Management.J Cardiothorac Vasc Anesth. 2021; 35: 2569-2591Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar This new guideline provides the most comprehensive recommendations to date and encompasses the time period from preoperative interventions, including management of antiplatelet and anticoagulant medication, to postoperative blood and fluid management. Recommendations cover the perioperative administration of pharmacologic agents, blood products and derivatives, as well as perfusion interventions, blood salvage techniques, and the use of transfusion algorithms, with an eye toward resource management in cardiac surgery. Patient blood management focuses on managing anemia, optimizing coagulation, interdisciplinary blood conservation modalities, and patient-centered decision-making, in order to achieve improved patient outcomes. In many aspects, cardiac anesthesiologists are involved directly and ideally positioned to take on leadership roles to ensure compliance and success. Pertinent key points are highlighted in Figure 1. The following narrative summarizes the key points from the current Guidelines that are either new or modified from the 2011 publication, or are unchanged but felt to be high priority patient blood management activities. One of the most significant determinants of patients requiring a perioperative blood transfusion is preoperative anemia. In patients who have preoperative anemia, in those who refuse blood transfusion, or in those who are deemed highrisk for postoperative anemia, it is reasonable to administer preoperative erythropoietin-stimulating agents and iron supplementation several days before cardiac surgery to increase red cell mass (class IIA, level B-R).2Weltert L Rondinelli B Bello R et al.A single dose of erythropoietin reduces perioperative transfusions in cardiac surgery: Results of a prospective single-blind randomized controlled trial.Transfusion. 2015; 55: 1644-1654Crossref PubMed Scopus (64) Google Scholar, 3Weltert L D'Alessandro S Nardella S et al.Preoperative very short term, high-dose erythropoietin administration diminishes blood transfusion rate in off-pump coronary artery bypass: a randomized blind controlled study.J Thorac Cardiovasc Surg. 2010; 139: 621-626Abstract Full Text Full Text PDF PubMed Scopus (75) Google Scholar, 4Penny-Dimri JC Cochrane AD Perry LA et al.Characterising the role of perioperative erythropoietin for preventing acute kidney injury after cardiac surgery: Systematic review and meta-analysis.Heart Lung Circ. 2016; 25: 1067-1076Abstract Full Text Full Text PDF PubMed Scopus (23) Google Scholar Nonvitamin-K antagonist oral anticoagulants (NOACs) (dabigatran [thrombin inhibitor], apixaban, betrixaban, edoxaban, and rivaroxaban [factor Xa inhibitors]) are a new subgroup of pharmacologic agents that have achieved widespread use since the 2011 publication of these guidelines. They currently are a preferred alternative to the vitamin K antagonist, warfarin, for stroke prevention in nonvalvular atrial fibrillation as well as in the treatment of venous thromboembolism.5De Caterina R Ageno W Agnelli G et al.The non-vitamin K antagonist oral anticoagulants in heart disease: Section V-special situations.Thromb Haemost. 2019; 119: 14-38Crossref PubMed Scopus (22) Google Scholar In patients in need of emergent cardiac surgery with recent ingestion of a NOAC or laboratory evidence of a NOAC effect, administration of the reversal antidote specific to that NOAC is recommended (ie, administer idarucizumab for dabigatran at the appropriate dose or administer andexanet-alpha for either apixaban or rivaroxaban at the appropriate dose). If the antidote for the specified NOAC is not available, prothrombin complex concentrate is recommended, recognizing that the effective response may be variable (class IIA, level C-LD).5De Caterina R Ageno W Agnelli G et al.The non-vitamin K antagonist oral anticoagulants in heart disease: Section V-special situations.Thromb Haemost. 2019; 119: 14-38Crossref PubMed Scopus (22) Google Scholar However, an advantage of administration of prothrombin complex concentrate is that it provides for rapid restoration of vitamin K-dependent coagulation factor levels without exposure to allogeneic blood and without the deleterious effects of volume overload that may accompany an equipotent dose of plasma.1Tibi P McClure RS Huang J et al.STS/SCA/AmSECT/SABM Update to the Clinical Practice Guidelines on Patient Blood Management.J Cardiothorac Vasc Anesth. 2021; 35: 2569-2591Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar Dual-antiplatelet therapy, with a P2Y12 inhibitor and aspirin, is well-demonstrated to decrease ischemic risk and thrombotic complications in patients with acute coronary syndromes. The most commonly used P2Y12 inhibitors in the setting of acute coronary syndromes and percutaneous coronary interventions have been clopidogrel, prasugrel, and ticagrelor. In order to reduce bleeding in patients requiring elective cardiac surgery, ticagrelor should be withdrawn preoperatively for a minimum of three days,6Hansson EC Jideus L Aberg B et al.Coronary artery bypass grafting related bleeding complications in patients treated with ticagrelor or clopidogrel: A nationwide study.Eur Heart J. 2016; 37: 189-197Crossref PubMed Scopus (122) Google Scholar clopidogrel for five days,6Hansson EC Jideus L Aberg B et al.Coronary artery bypass grafting related bleeding complications in patients treated with ticagrelor or clopidogrel: A nationwide study.Eur Heart J. 2016; 37: 189-197Crossref PubMed Scopus (122) Google Scholar and prasugrel for seven days (class I, level B-NR).7Smith PK Goodnough LT Levy JH et al.Mortality benefit with prasugrel in the TRITON-TIMI 38 coronary artery bypass grafting cohort: Risk-adjusted retrospective data analysis.J Am Coll Cardiol. 2012; 60: 388-396Crossref PubMed Scopus (145) Google Scholar,8Valgimigli M Bueno H Byrne RA et al.2017 ESC focused update on dual antiplatelet therapy in coronary artery disease developed in collaboration with EACTS.Eur J Cardiothorac Surg. 2018; 53: 34-78Crossref PubMed Scopus (170) Google Scholar Antifibrinolytic agents currently used in patients undergoing cardiac surgery include the synthetic lysine analogs, tranexamic acid and epsilon aminocaproic acid. Use of these synthetic antifibrinolytic agents reduces blood loss and blood transfusion during cardiac procedures, and their use is indicated for blood conservation9Myles PS Smith JA Forbes A et al.Tranexamic acid in patients undergoing coronary-artery surgery.N Engl J Med. 2017; 376: 136-148Crossref PubMed Scopus (185) Google Scholar,10Raghunathan K Connelly NR Kanter GJ. epsilon-Aminocaproic acid and clinical value in cardiac anesthesia.J Cardiothorac Vasc Anesth. 2011; 25: 16-19Abstract Full Text Full Text PDF PubMed Scopus (24) Google Scholar (class I, level A). Tranexamic acid reduces bleeding and total transfusion during off-pump coronary artery bypass grafting surgery (class IIA, level B-R). Topical application of antifibrinolytic agents to the surgical site after cardiopulmonary bypass (CPB) is reasonable to limit chest tube drainage and transfusion requirements after cardiac surgery, although no single topical preparation emerges as the agent of choice for localized bleeding that is difficult to control (class IIA, level B-R). Goal-directed transfusion algorithms that incorporate point-of-care testing, such as with viscoelastic devices, are recommended to reduce periprocedural bleeding and transfusion in cardiac surgical patients11Karkouti K Callum J Wijeysundera DN et al.Point-of-care hemostatic testing in cardiac surgery: A stepped-wedge clustered randomized controlled trial.Circulation. 2016; 134: 1152-1162Crossref PubMed Scopus (155) Google Scholar (class I, level B-R). Point-of-care monitoring of the hemostatic system is critical to provide timely and accurate assessment of the cause of bleeding, with potential to provide targeted therapies. Prophylactic use of plasma in cardiac surgery in the absence of coagulopathy is not indicated, does not reduce blood loss, and exposes patients to unnecessary risks and complications of allogeneic blood component transfusion (class III: harm, level A). Routine use of red cell salvage using centrifugation is helpful for blood conservation and minimizes post-CPB allogeneic red blood cell transfusion in cardiac surgery (class I, level A). Direct reinfusion of shed mediastinal blood from postoperative chest tube drainage is not recommended as a means of blood conservation and may cause harm (class III: harm, level B-NR). Acute normovolemic hemodilution is a method intended to limit loss of red blood cell mass by sequestration of a portion of the patient's blood volume before CPB. Acute normovolemic hemodilution is a reasonable method to reduce bleeding and transfusion (class IIA, level of evidence A).12Barile L Fominskiy E Di Tomasso N et al.Acute normovolemic hemodilution reduces allogeneic red blood cell transfusion in cardiac surgery: A systematic review and meta-analysis of randomized trials.Anesth Analg. 2017; 124: 743-752Crossref PubMed Scopus (94) Google Scholar Retrograde autologous priming of the CPB circuit should be used wherever possible (class I, level B-R). Throughout most recent studies, the volume of clear prime that is displaced is an important criterion contributing to the effectiveness of retrograde autologous priming in reducing blood transfusions.13Hofmann B Kaufmann C Stiller M et al.Positive impact of retrograde autologous priming in adult patients undergoing cardiac surgery: A randomized clinical trial.J Cardiothorac Surg. 2018; 13: 50Crossref PubMed Scopus (22) Google Scholar This is similar to the way in which a reduced priming volume can be effective in reducing blood transfusion. Reduced priming volume in the CPB circuit reduces hemodilution and is indicated for blood conservation (class I, level B-NR). The adoption of a combined strategy of surgical approach, anesthesia, and perfusion management, along with CPB circuit features designed to minimize hemodilution and optimize biocompatibility, have been termed "minimally invasive extracorporeal circulation" and are reasonable to reduce blood loss and red cell transfusion as part of a combined blood conservation approach (class IIA, level B-R). In patients undergoing cardiac surgery, a restrictive perioperative allogeneic RBC transfusion strategy (transfusion trigger between 7 and 8 g/dL) is recommended in preference to a liberal transfusion strategy (transfusion trigger between 8 and 10 g/dL) for perioperative blood conservation. This restrictive strategy reduces both transfusion rate and units of allogeneic RBCs without increased risk of mortality or morbidity (class I, level A). Allogeneic RBC transfusion is unlikely to improve oxygen transport when the hemoglobin concentration is greater than 10 g/dL and is not recommended (class III: no benefit; level B-R).14 It is reasonable to administer human albumin after cardiac surgery to provide intravascular volume replacement and minimize the need for transfusion (class IIA, level B-R). Hydroxyethyl starch is not recommended as a volume expander in CPB patients, as it may increase the risk of bleeding (class III: no benefit, level B-R). This 2021 STS/SCA/AmSECT/SABM updated patient blood management guidelines stress the importance of an evidence-based, multimodal, and multidisciplinary approach to preserving a patient's blood and conserving resources so as to optimize outcomes in patients who are at high risk for transfusion. A standardized protocol for evidence-based patient blood management leads to a patient-centered approach to blood conservation in the perioperative setting and favors improved clinical outcomes in cardiopulmonary procedures.