IJCS | Volume 33, Nº3, May / June 2020

DOI: https://doi.org/10.36660/ijcs.20190043 235 ORIGINAL ARTICLE International Journal of Cardiovascular Sciences. 2020; 33(3):235-242 Mailing Address: Fernando Torres Praça Santos Andrade, 01, Centro. Postal Code: 84030-900, Ponta Grossa, PR - Brazil. E-mail: fernandolimatorres@hotmail.com A Retrospective Study on Unfractionated Bovine Heparin Safety in On-Pump Cardiac Surgery Fernando Antonio de Lima Torres, 1 Andressa C. B. Torres, 2 A llinson Ribeiro, 2 C auê O. Maia, 2 F ernanda P. Almeida, 2 J oão Roceto, 2 J orge A. Matkovski, 2 M atheus G. Kovalski, 2 V anessa A. Pizato, 2 T atiana M. G. Cordeiro 2 Instituto de Cirurgia do Coração, Hospital Bom Jesus, 1 Ponta Grossa, Paraná, PR - Brazil Universidade Estadual de Ponta Grossa, 2 Paraná, PR - Brazil Manuscript received on February 02, 2019; reviewed on June 20, 2019; accepted on August 07, 2019. Abstract Background: Heparin decreases the risks of thrombotic phenomena in extracorporeal circulation. However, it must present a robust safety profile itself, especially for bleeding. Contamination of porcine heparin demands an alternative source and consequent assessment of safety. Objective: To evaluate the safety of unfractionated bovine heparin during on-pump cardiac surgery. Methods: Descriptive, retrospective study, evaluating medical records from all patients who had on-pump cardiac surgery over four years. We observed the occurrence of bleeding, thrombocytopenia, postoperative vasoplegia, activated clotting time values and any other coagulation phenomena as safety profile parameters. Results: We evaluated 204 medical records reporting the use of unfractionated bovine heparin. 66.18% of the patients presented thrombocytopenia, 1.04% presented bleeding of more than 2000 mL in the first 24 hours of the postoperative period. One patient presented clots in the surgical field. Median activated clotting time was 137 seconds at baseline, 803 seconds after the first dose of heparin and, after protamine, it returns to similar baseline values, that is, 149.5 seconds. Conclusion: Unfractionated bovine heparin did not present unusual adverse effects and can be considered safe for on-pump cardiac surgery. (Int J Cardiovasc Sci. 2020; 33(3):235-242) Keywords: Blood Coagulation Tests; Heparin/analysis, Heparin/chemistry, Heparin/standards; Cardiac Surgery; Safety; Extracorporeal, Circulation. Introduction Extracorporeal circulation (ECC) is a crucial component of cardiac surgery. Even with the progress of medicine, ECC remains a procedurewith risks, including thrombotic phenomena, arrhythmia, bleeding, and neurologic disfunction. 1,2 Heparin is an anticoagulant agent routinely used with ECC. The ideal anticoagulant product must be effective, safe and easy to monitor, without significant interindividual differences. A balancemust exist between heparin’s efficacy (avoiding thrombotic phenomena) and safety (avoiding bleeding) in ECC. 2 Heparin was initially isolated from dog liver. Since then, we have used different animals and tissues, such as porcine and bovine intestinal mucosa and bovine and sheep lungs. 3-5 The search for alternatives to bovine heparin started in the 1990s because of bovine spongiform encephalopathy, which had the potential to contaminate heparin with prions. 6 Currently, the exploration of heparin from alternative animal sources and the reintroduction of bovine heparin have become more relevant after contamination of unfractionated porcine heparin (UFH) with oversulfated chondroitin sulfate, leading to serious adverse effects, such as