Portal de Periódicos da CAPES

STS/SCA/AmSECT/SABM Update to the Clinical Practice Guidelines on Patient Blood Management

2021; Elsevier BV; Volume: 112; Issue: 3 Linguagem: Inglês

10.1016/j.athoracsur.2021.03.033

1552-6259

Pierre Tibi, R. Scott McClure, Jiapeng Huang, Robert A. Baker, David Fitzgerald, C. David Mazer, Marc E. Stone, Danny Chu, Alfred H. Stammers, Tim Dickinson, Linda Shore‐Lesserson, Victor A. Ferraris, Scott Firestone, Kalie Kissoon, Susan D. Moffatt‐Bruce,

Trauma, Hemostasis, Coagulopathy, Resuscitation

Dr Stammers discloses a financial relationship with SpecialtyCare.The Appendices can be viewed in the online version of this article [https://doi.org/10.1016/j.athoracsur.2021.03.033] on https://www.annalsthoracicsurgery.org. Dr Stammers discloses a financial relationship with SpecialtyCare. The Appendices can be viewed in the online version of this article [https://doi.org/10.1016/j.athoracsur.2021.03.033] on https://www.annalsthoracicsurgery.org. Owing to the constantly evolving nature of the medical literature, The Society of Thoracic Surgeons (STS) clinical practice guidelines periodically undergo evaluation and updating. A multidisciplinary panel of experts was convened by STS, which includes members of the Society of Cardiovascular Anesthesiologists (SCA), the American Society of ExtraCorporeal Technology (AmSECT), and the Society for the Advancement of Blood Management (SABM), to review the latest data on patient blood management and to update the 2011 Update to The Society of Thoracic Surgeons and the Society of Cardiovascular Anesthesiologists Blood Conservation Clinical Practice Guidelines. The concept of patient blood management informs the recommendations in this document and stresses the importance of an evidence-based, multimodal, and multidisciplinary approach to not just conserving blood resources but also optimizing outcomes in patients at high risk for transfusion. The individual recommendations are meant to be conceived of as part of an all-inclusive protocol-based and shared decision-making approach rather than isolated interventions to reduce blood loss and transfusion. Because standards for clinical practice guidelines have evolved since 2011, the authors were tasked with prioritizing topics for systematic review, while still aiming for the comprehensive approach of previous versions of this article. These high-priority topics make up the bulk of this article and resulted in 23 new or updated recommendations. Additionally, all previous recommendations not directly addressed were voted on by consensus and can be found in Table 1. Together, these recommendations address the full spectrum of care for patients undergoing cardiac surgery, as seen in Table 2.Table 1Updated Recommendations From Previous Guidelines That Are Not a Focus of the ArticleInterventionACC/AHA Class and LevelPreoperative identification of high-risk patients should be performed, and all available preoperative and perioperative measures of blood conservation should be undertaken in this group as they account for the majority of blood products transfused.Class I, Level AIt is reasonable to discontinue low-intensity antiplatelet drugs (eg, aspirin) only in purely elective patients without acute coronary syndromes before operation with the expectation that blood transfusion will be reduced.Class IIA, Level AMinimization of phlebotomy through a reduction in blood sampling volumes and frequencies is a reasonable means of blood conservation.Class IIA, Level B-NR (Nonrandomized)The addition of a P2Y12 inhibitor to aspirin therapy, if indicated, in the immediate postoperative care of coronary artery bypass grafting patients prior to ensuring surgical hemostasis may increase bleeding and the need for surgical reexploration, and is not recommended until the risk of bleeding has abated.Class III: No Benefit, Level C-LD (Limited Data)Use of 1-deamino-8-d-arginine vasopressin (DDAVP) may be reasonable to attenuate excessive bleeding and transfusion in certain patients with demonstrable and specific platelet dysfunction known to respond to this agent (eg, uremic or CPB-induced platelet dysfunction, type I von Willebrand disease).Class IIB, Level B-NRPlasma transfusion is reasonable in patients with serious bleeding in the context of multiple or single coagulation factor deficiencies when safer fractionated products are not available.Class IIA, Level B-NRProphylactic use of plasma in cardiac operations 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 AWhen allogeneic blood transfusion is needed, it is reasonable to use leukoreduced donor blood, if available.Class IIA, Level B-R (Randomized)Use of recombinant factor VIIa concentrate may be considered for the management of intractable nonsurgical bleeding that is unresponsive to routine hemostatic therapy after cardiac procedures using CPB.Class IIB, Level B-NRAntithrombin III concentrates are indicated to reduce plasma transfusion in patients with antithrombin-mediated heparin resistance immediately before CPB.Class I, Level AIn high-risk patients with known malignancy who require CPB, blood salvage using centrifugation of salvaged blood from the operative field may be considered when allogeneic transfusion is required.Class IIB, Level B-NRCentrifugation of pump-salvaged blood is reasonable for minimizing post-CPB allogeneic red blood cell transfusion.Class IIA, Level AUse of modified ultrafiltration may be reasonable for blood conservation and reducing postoperative blood loss in adult cardiac operations using CPB.Class IIB, Level B-RRoutine use of red cell salvage using centrifugation is helpful for blood conservation in cardiac operations using CPB.Class I, Level ADirect 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-NRA comprehensive multimodality blood conservation program led by a multidisciplinary team of health care providers should be part of any patient blood management program to limit utilization of blood resources and decrease the risk of bleeding.Class I, Level B-RACC, American College of Cardiology; AHA, American Heart Association; CPB, cardiopulmonary bypass. Open table in a new tab Table 2All Current Recommendations for Patient Blood Management, Classified by Intervention Type and in Descending Order of Class of Recommendation and Level of EvidenceInterventionACC/AHA Class and LevelPreoperative interventions Preoperative identification of high-risk patients should be performed, and all available preoperative and perioperative measures of blood conservation should be undertaken in this group as they account for the majority of blood products transfused.Class I, Level A Assessment of anemia and determination of its etiology is appropriate in all patients undergoing cardiac surgery, and it is reasonable to treat with intravenous iron preparations if time permits.Class IIA, Level B-R In patients undergoing cardiac operations, it is reasonable to implement standardized transfusion protocols in order to reduce transfusion burden.Class IIA, Level B-R In patients who have (i) preoperative anemia, (ii) refuse blood transfusion, (iii) or are deemed high-risk for postoperative anemia, it is reasonable to administer preoperative erythropoietin-stimulating agents and iron supplementation several days prior to cardiac operations to increase red cell mass.Class IIA Level B-R Minimization of phlebotomy by reduced volume and frequency of blood sampling is a reasonable means of blood conservation.Class IIA, Level B-NR Preoperative treatment of asymptomatic anemia and thrombocytopenia with transfusion is of uncertain benefit.Class III: No Benefit, Level B-NRPreoperative antiplatelet management In order to reduce bleeding in patients requiring elective cardiac surgery, ticagrelor should be withdrawn preoperatively for a minimum of 3 days, clopidogrel for 5 days, and prasugrel for 7 days.Class I, Level B-NR It is reasonable to discontinue low-intensity antiplatelet drugs (eg, aspirin) only in purely elective patients without acute coronary syndromes before operation with the expectation that blood transfusion will be reduced.Class IIA, Level A Laboratory and/or point-of-care measurement of antiplatelet drug effect in patients having received recent dual-antiplatelet therapy can be useful to assess bleeding risk or to guide timing of surgery.Class IIA, Level B-R The addition of a P2Y12 inhibitor to aspirin therapy, if indicated, in the immediate postoperative care of coronary artery bypass grafting patients prior to ensuring surgical hemostasis may increase bleeding and the need for surgical reexploration and is not recommended until the risk of bleeding has abated.Class III: No Benefit, Level C-LDPreoperative anticoagulants In patients in need of emergent cardiac surgery with recent ingestion of a nonvitamin K oral anticoagulant (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 appropriate dose or administer andexanet-α for either apixaban or rivaroxaban at appropriate dose).Class IIA, Level C-LD If the antidote for the specified NOAC is not available, prothrombin concentrate is recommended, recognizing that the effective response may be variable.Class IIA, Level C-LDPharmacologic agents Use of synthetic antifibrinolytic agents such as epsilon-aminocaproic acid (EACA) or tranexamic acid reduce blood loss and blood transfusion during cardiac procedures and are indicated for blood conservation.Class I, Level A Tranexamic acid reduces bleeding and total transfusion during off pump coronary artery bypass graft 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 operations using CPB.Class IIA, Level B-R Use of 1-deamino-8-D-arginine vasopressin (DDAVP) may be reasonable to attenuate excessive bleeding and transfusion in certain patients with demonstrable and specific platelet dysfunction known to respond to this agent (eg, uremic or CPB-induced platelet dysfunction, type I von Willebrand disease).Class IIB, Level B-NRBlood products and derivatives Antithrombin III concentrates are indicated to reduce plasma transfusion in patients with antithrombin mediated heparin resistance immediately before cardiopulmonary bypass.Class I, Level A When allogeneic blood transfusion is needed, it is reasonable to use leukoreduced donor blood, if available.Class IIA, Level B-R Plasma transfusion is reasonable in patients with serious bleeding in the context of multiple or single coagulation factor deficiencies when safer fractionated products are not available.Class IIA, Level B-NR Prothrombin concentrate is reasonable to consider over fresh frozen plasma as first-line therapy for refractory coagulopathy in cardiac surgery in select situations to reduce bleeding.Class IIA, Level B-NR Use of recombinant factor VIIa concentrate may be considered for the management of intractable nonsurgical bleeding that is unresponsive to routine hemostatic therapy after cardiac procedures using CPB.Class IIB, Level B-NR Prophylactic use of plasma in cardiac operations 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 APerfusion interventions Retrograde autologous priming of the CPB circuit should be used wherever possible.Class I, Level B-R Reduced priming volume in the CPB circuit reduces hemodilution and is indicated for blood conservation,Class I, Level B-NR Acute normovolemic hemodilution (ANH) is a reasonable method to reduce bleeding and transfusion.Class IIA, Level A Minimally invasive extracorporeal circulation is reasonable to reduce blood loss and red cell transfusion as part of a combined blood conservation approach.Class IIA, Level B-R Use of modified ultrafiltration may be reasonable for blood conservation and reducing postoperative blood loss in adult cardiac operations using CPB.Class IIB, Level B-RBlood salvage interventions Routine use of red cell salvage using centrifugation is helpful for blood conservation in cardiac operations using CPB.Class I, Level A Centrifugation of pump-salvaged blood is reasonable for minimizing post-CPB allogeneic red blood cell transfusion.Class IIA, Level A In high-risk patients with known malignancy who require CPB, blood salvage using centrifugation of salvaged blood from the operative field may be considered when allogeneic transfusion is required.Class IIB, Level B-NR 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-NRPostoperative fluid management 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, B-RTransfusion algorithms In patients undergoing cardiac surgery, a restrictive perioperative allogeneic red blood cell (RBC) transfusion strategy is recommended in preference to a liberal transfusion strategy for perioperative blood conservation, as it reduces both transfusion rate and units of allogeneic RBCs without increased risk for mortality or morbidity.Class I, Level A Goal directed transfusion algorithms which incorporate point of care testing, such as with viscoelastic devices, are recommended to reduce periprocedural bleeding and transfusion in cardiac surgical patients.Class I, Level B-R 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-RManagement of blood resources A comprehensive multimodality blood conservation program led by a multidisciplinary team of health care providers should be part of any patient blood management program to limit utilization of blood resources and decrease the risk of bleeding.Class I, Level B-RACC, American College of Cardiology; AHA, American Heart Association. Open table in a new tab ACC, American College of Cardiology; AHA, American Heart Association; CPB, cardiopulmonary bypass. ACC, American College of Cardiology; AHA, American Heart Association. Blood transfusion is a critical and life-saving facet of the care for cardiothoracic surgery patients. Inherent to the transfusing of blood is the understanding of the preservation of blood as well as the appropriateness of techniques to prevent hemorrhage through the clinical course. Although clinical practices have evolved through the centuries since Dr William Harvey discovered the circulation of blood in 1628 and attempted the first blood transfusion thereafter, there is significant variability in the practices of blood transfusion and conservation in all phases of the surgical care. In our current health care environment of value-based care, the need for practice guidelines must therefore be further emphasized. Additionally, the term “blood conservation” is yielding to a broader term “patient blood management” (PBM) that incorporates the need to not only “conserve” blood but, more importantly, to also take into account the assessment of the liquid organ, blood, as a vital entity in taking care of the surgical patient. PBM is the broad implementation of many factors in a multidisciplinary fashion as opposed to just choosing isolated recommendations. The 4 major tenets of PBM are (1) managing anemia, (2) optimizing coagulation, (3) interdisciplinary blood conservation modalities, and (4) patient-centered decision making in order to achieve improved patient outcomes. Surgical outcomes are now being held to a higher standard, and sharing of outcomes, often in very public forums, is the new normal. Additionally, resource utilization and efficient care has to be foundational to our provision of care for every cardiothoracic surgery patient. High-value care with excellent outcomes by using the appropriate resources is now at the forefront of health care delivery. This was a collective project of STS, SCA, AmSECT, and SABM to review the current literature, revise previous guidelines, and develop a series of practice guidelines that reflect the current evidence and practice portfolios that are used in cardiothoracic surgery in North America. Critical to this review and guideline development was an understanding of the patient care paradigm throughout the care continuum. The care continuum consisted of exploring the informed consent process, preoperative conditioning, the current clinical use of antiplatelet agents and preoperative anticoagulants, intraoperative blood management (including intravenous and topic hemostatic agent use), and the postoperative management of patients undergoing cardiopulmonary bypass (CPB). There are many stakeholders in the management of blood for patients throughout their clinical course, and therefore, we sought to include the evidence and practice of many different groups and experts. Ultimately, we sought to provide a comprehensive set of guidelines that are practical and will be received as being reasonable and well-researched. While we have collectively tried to accumulate the evidence and data from a broad number of stakeholders and sources, we recognize that it may be impossible to have every data point. Our intent is to present the most comprehensive set of guidelines possible, and we hope that this will serve as a resource so to improve the outcomes of patients undergoing cardiothoracic surgery. The STS Workforce on Evidence-Based Surgery assembled a Task Force in 2018 to update the 2011 STS/SCA Blood Conservation Clinical Practice Guidelines, seeking representatives again from SCA as well as AmSECT and SABM. The members of the writing committee submitted conflict of interest disclosure forms, which were reviewed by the Chair and STS staff before confirmation for potential conflicts from relevant relationships with industry. The writing committee reviewed the topics covered by the 2011 Guidelines and developed 11 questions in the Population, Intervention, Comparator, and Outcomes format (PICO) intended to focus on the highest priority and most clinically impactful areas for a systematic review. The PICO questions were sent to a research librarian in March 2018 to develop a strategy to identify relevant articles published in English since 2009, the most recent year of data included in the previous guidelines. Strategies were developed for both MEDLINE and Embase, the details for which may be found in Appendix 1. Reference lists were manually scanned for additional relevant results. This strategy resulted in 1227 potentially relevant abstracts, which were screened by a group of authors (S.F., K.K., R.S.M., D.C.). A total of 87 articles met the inclusion criteria. The primary reasons for exclusion were if the population was not relevant (eg, patients undergoing percutaneous coronary intervention [PCI] or another type of surgery aside from cardiac) or the primary outcomes were secondary markers with an uncertain relationship to the hard clinical outcomes selected by the writing committee. Two authors (S.F., K.K.) developed an evidence table of the relevant papers (Appendix 2) and rated the studies for risk of bias. The Newcastle-Ottawa scale was used for observational studies (Appendix 3), and a custom-made checklist was used for randomized control trials (RCTs) and meta-analyses (Appendix 4). The bulk of the article is focused on the results of this systematic review. Recommendations from previous versions of this article were assessed by an electronic survey circulated to the authors to determine their current relevance. A full account of the evolution of the recommendations on this topic is in Appendix 5, which shows that many previous recommendations were retired for lack of current clinical relevance, having outdated techniques, or lack of improvement in the evidence for the weaker statements. Recommendations that are not a focus of this updated article, but which were maintained in this version due to having continued clinical relevance, are included in Table 1. All current and valid recommendations are categorized and presented in Table 2. Voting on recommendations used a modified Delphi method of 3 rounds of voting to reach consensus, in which responses were required by 80% of the authors, with 75% agreement on class and level of evidence as defined by the American College of Cardiology (ACC)/American Heart Association (AHA) Classification System (Appendix 6). The resulting article was reviewed by the STS Workforce on Evidence-Based Surgery, the STS Council Operating Board on Quality, Research, and Patient Safety, and the Executive Committee, along with a 2-week member comment period available to members of every participating society. The Board of Directors of the SCA and AmSECT also reviewed the document before publication. These guidelines were developed by the participating societies without commercial support and will be reviewed for a potential update within 5 years of publication. •Assessment of anemia and determination of its etiology is appropriate in all patients undergoing cardiac surgery, and it is reasonable to treat with intravenous iron preparations if time permits. (Class IIA, Level B-R) It is well known from the original 2007 STS Blood Conservation Guidelines that preoperative preparation of patients with regard to blood use in cardiac surgery, when feasible, is of the utmost importance for consistent blood conservation strategies. Identification of high-risk individuals, whether it be from advanced age, preoperative anemia, or abnormal coagulation profiles, is a Class 1 intervention. Additionally, one of the most significant determinants of patients needing perioperative transfusions is preoperative anemia. Anemia is extremely prevalent in the cardiac surgical population, especially in elderly patients or patients with multiple comorbidities and chronic diseases. Recent studies identify the prevalence of anemia in the 30% to 40% range1Klein A.A. Collier T.J. Brar M.S. et al.The incidence and importance of anaemia in patients undergoing cardiac surgery in the UK – the first Association of Cardiothoracic Anaesthetists national audit.Anaesthesia. 2016; 71: 627-635Crossref PubMed Scopus (81) Google Scholar,2Munoz M. Laso-Morales M.J. Gomez-Ramirez S. Cadellas M. Nunez-Matas M.J. Garcia-Erce J.A. Pre-operative haemoglobin levels and iron status in a large multicentre cohort of patients undergoing major elective surgery.Anaesthesia. 2017; 72: 826-834Crossref PubMed Scopus (73) Google Scholar and severe anemia by World Health Organization classification of hemoglobin of less than 8 g/dL in the 8% to 10% range.3von Heymann C. Kaufner L. Sander M. et al.Does the severity of preoperative anemia or blood transfusion have a stronger impact on long-term survival after cardiac surgery?.J Thorac Cardiovasc Surg. 2016; 152: 1412-1420Abstract Full Text Full Text PDF PubMed Google Scholar Iron deficiency is the most prevalent cause of anemia in the cardiac surgical population, occurring in up to 50% of anemic patients.4Hung M. Besser M. Sharples L.D. Nair S.K. Klein A.A. The prevalence and association with transfusion, intensive care unit stay and mortality of pre-operative anaemia in a cohort of cardiac surgery patients.Anaesthesia. 2011; 66: 812-818Crossref PubMed Scopus (78) Google Scholar Patients with preoperative anemia are more likely to require transfusions, and it is obvious that if the ability to treat iron-deficiency anemia is available without any untoward effects, it should be instituted before surgery. Differentiation must be made between anemias caused by iron deficiency as opposed to other causes of anemia. Iron-deficiency anemia is usually microcytic, whereas normocytic or macrocytic anemia stem from a variety of causes. Routine iron studies are of importance in the determination of the type of anemia present and should be done routinely in the careful preoperative assessment of patients so that treatment can be instituted if warranted. There is a distinct correlation between preoperative anemia and worse clinical outcomes in most studies. Usually, the greater the anemia, the more severe the complications. In a prospective observational study of more than 200 patients undergoing coronary artery bypass graft (CABG) surgery, preoperative hematocrit remained an independent predictor for major morbidity (odds ratio [OR], 0.95; P = .01), while transfusion was also a strong predictor (OR, 4.86; P < .001).5Spiegelstein D. Holmes S.D. Pritchard G. Halpin L. Ad N. Preoperative hematocrit as a predictor of perioperative morbidities following nonemergent coronary artery bypass surgery.J Card Surg. 2015; 30: 20-26Crossref PubMed Google Scholar Multiple recent retrospective studies demonstrate higher morbidity and mortality in patients with preoperative anemia, although some only show an association with long-term mortality. Additionally, there appears to be a cumulative effect of anemia and transfusions that increases risks. In comparisons of patients undergoing CABG surgery who did or did not receive a transfusion, there was greater mortality in the patients who received a transfusion (11% vs 5.3%; P = .001). Patients with anemia who received a transfusion had a hazard rate for mortality 3-times higher than nonanemic patients who did not receive transfusion (hazard ratio [HR], 2.918; 95% confidence interval [CI], 1.512-5.633; P = .001), and twice that of anemic patients who did not receive a transfusion (HR, 2.087; 95% CI, 1.004-4.336; P = .049).6Engoren M. Schwann T.A. Habib R.H. Neill S.N. Vance J.L. Likosky D.S. The independent effects of anemia and transfusion on mortality after coronary artery bypass.Ann Thorac Surg. 2014; 97: 514-520Abstract Full Text Full Text PDF PubMed Scopus (52) Google Scholar Preoperative anemia has also been associated with increased transfusion rates and longer intensive care unit (ICU) and hospital lengths of stay1Klein A.A. Collier T.J. Brar M.S. et al.The incidence and importance of anaemia in patients undergoing cardiac surgery in the UK – the first Association of Cardiothoracic Anaesthetists national audit.Anaesthesia. 2016; 71: 627-635Crossref PubMed Scopus (81) Google Scholar and an increase in acute kidney injury.7Oprea A.D. Del Rio J.M. Cooter M. et al.Pre- and postoperative anemia, acute kidney injury, and mortality after coronary artery bypass grafting surgery: a retrospective observational study.Can J Anaesth. 2018; 65: 46-59Crossref PubMed Scopus (13) Google Scholar However, 1 retrospective study found only normocytic or macrocytic anemia was associated with increased adverse events.8Dai L. Mick S.L. McCrae K.R. et al.Preoperative anemia in cardiac operation: does hemoglobin tell the whole story?.Ann Thorac Surg. 2018; 105: 100-107Abstract Full Text Full Text PDF PubMed Scopus (15) Google Scholar •In patients who have (i) preoperative anemia, (ii) refuse blood transfusion, (iii) or are deemed high-risk for postoperative anemia, it is reasonable to administer preoperative erythropoietin stimulating agents (ESA) and iron supplementation several days prior to cardiac operations to increase red cell mass. (Class IIA, Level B-R) Among the difficulties in treatment of the anemic patient is the oftentimes lack of a safe waiting period, the “gentle” insistence by referring physicians for more urgent treatment than is necessary, the inconvenience, cost, and/or refusal to pay for iron and EPO therapy by insurers and the oftentimes overstated risks of these therapies. Nevertheless, treatment of an anemic patient before surgery is an appropriate preoperative intervention and should be considered as part of any patient’s careful workup and preparation for cardiac surgery, if time permits. The treatment of anemia before heart surgery has been significantly studied, but almost all trials combine treatment of iron deficiency with both iron preparations and erythropoietin (EPO). Many of these studies, although not all, show increases in hemoglobin levels and reductions in transfusions. There is a paucity of studies that treat preoperative iron-deficiency anemia with just iron. One prospective observational study demonstrated an increased hemoglobin level in pretreated anemic patients,9Peters F. Eveslage M. Gallitz I. et al.Post-operative iron carboxymaltose may have an effect on haemoglobin levels in cardiothoracic surgical patients on the ICU - an observational pilot study about anaemia treatment with intravenous iron.Transfus Med Hemother. 2018; 45: 42-46Crossref PubMed Scopus (3) Google Scholar but a small RCT of only 50 patients did not.10Padmanabhan H. Siau K. Nevill A.M. et al.Intravenous iron does not effectively correct preoperative anaemia in cardiac surgery: a pilot randomized controlled trial.Interact Cardiovasc Thorac Surg. 2019; 28: 447-454Crossref PubMed Scopus (15) Google Scholar Therefore, it is difficult to confidently state that the direct treatment of iron-deficiency anemia before cardiac surgery with iron alone will result in improved outcomes, but it is clear that the treatment of anemia is warranted in the elective surgical patient. Patients should undergo careful preoperative testing to rule out absolute or functional iron deficiency and be treated accordingly if possible. EPO therapy, if begun a few days preoperatively, may reduce adverse outcomes by augmenting red cell mass in anemic patients treated with iron. A small RCT by Yoo and colleagues11Yoo Y.C. Shim J.K. Kim J.C. Jo Y.Y. Lee J.H. Kwak Y.L. Effect of single recombinant human erythropoietin injection on transfusion requirements in preoperatively anemic patients undergoing valvular heart surgery.Anesthesiology. 2011; 115: 929-937Crossref P