IJCS | Volume 32, Nº6, November / December 2019

DOI: 10.5935/2359-4802.20190040 565 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2019;32(6):565-572 Mailing Address: Ana Paula Tagliari Rua Ramiro Barcelos, 2350. Postal Code: 90035-903, Porto Alegre, RS - Brazil. E-mail: atagliari@hcpa.edu.br Adverse Events and Risk Factors of Blood Transfusion in Cardiovascular Surgery: A Prospective Cohort Study Ana Paula Tagliari, 1 ,2 L ucas Molinari Veloso da Silveira, 1 A driano Nunes Kochi, 1, 2 A nderson Castro de Souza, 1 Marcelo Curcio Gib, 1, 2 T anara Martins de Freitas, 1 ,2 C ristiano Blaya Martins, 1, 2 L eandro Totti Cavazzola, 1, 2 O rlando Carlos BelmonteWender 1, 2 Universidade Federal do Rio Grande do Sul (UFRGS), 1 Porto Alegre, RS - Brazil Hospital de Clínicas de Porto Alegre (HCPA), 2 Porto Alegre, RS - Brazil Manuscript received on August 19, 2018, revised manuscript on December 05, 2018, accepted on February17, 2019. Abstract Background: Hemodilution, transoperative bleeding and cardiopulmonary bypass (CPB) are some of the factors associated with high transfusion rates in cardiac surgery. Objective: To analyze the incidence of blood transfusion and early postoperative outcomes in cardiac surgery patients. Methods: Cohort study of patients undergoing cardiac surgery in a university hospital, consecutively enrolled from May 2015 to February 2017. Data were prospectively collected and comparisons were made between two patients’ groups: transfused and not transfused. Student's t-test, chi-square test, and logistic regression were used, and a p-value < 0.05 was considered significant. Results: Among the 271 patients evaluated, 100 (37%) required transfusion in the transoperative (32.1%) and/or postoperative periods (19.5%). The following predictors of transfusion were identified by multivariate analysis: EuroScore II (OR 1.2); chronic kidney disease (CKD) (OR 3.2); transoperative bleeding ≥ 500 mL (OR 6.7); baseline hemoglobin (Hb) ≤ 10 g/dL (OR 11.5); activated partial thromboplastin time (aPTT) (OR 1.1) and CPB duration (OR 1.03). Transfusion was associated with prolonged mechanical ventilation (≥ 24h) (2.4% vs. 23%), delirium (5.9% vs. 18%), bronchopneumonia (1.2% vs. 16%), acute renal failure (3.5% vs. 25%), acute on CKD (0.6% vs. 8%), stroke or transient ischemic attack (1.8% vs. 8%), intensive care unit stay ≥ 72 h (36% vs. 57%), longer hospital stay (8 ± 4 days vs. 16 ± 15 days), as well as increased early mortality (1.75% vs. 15%). Conclusion: EuroScore II, CKD, major transoperative bleeding, preoperative Hb and aPTT values and CPB time were independent predictors of transfusion, which was associatedwith a higher rate of adverse outcomes, including early mortality. (Int J Cardiovasc Sci. 2019;32(6):565-572) Keywords: Cardiac Surgical Procedures/mortality; Blood Transfusion; Intraoperative Care/adverse effects; Postoperative Complications/prevention and control; Risk assessment. Introduction Hemodilution, transoperative bleeding and cardiopulmonary bypass (CPB) are some of the factors associatedwith high transfusion rates in cardiac surgery. 1 The prevalence of patients undergoing cardiac surgery who receive blood components is unknown, with values varying from 10% to 95%. 2-4 Such diversity is partly due to different local practices and institutional protocols. A Canadian retrospective study documented a red blood cell (RBC) transfusion rate ranging from 23.8% to 51.9%. 1 In another study, transfusion rates in coronary artery bypass grafting (CABG) varied from26.5 to 71.3%. 5 Moreover, as noted by Vonk et al., 6 there was 28% reduction in RBC transfusion in the last 10 years, with non-significant change in the use of fresh frozen plasma (FFP) or platelets. In 2011, 50% and 60% of patients needed FFP and platelets, respectively. 6