BackgroundThe incidence of significant post-operative bleeding after cardiac surgery is associated with high morbidity and mortality. Understanding the main risk factors associated with bleeding could help reduce the incidence of this complication. The objective of this study was to determine the associated risk factors of bleeding in a Mexican population of cardiac post-operative patients. MethodsThe study design was a prospective cohort, the recollected sample was 173 consecutive adult patients who underwent cardiac surgery with cardiopulmonary bypass (CPB) and aortic cross-clamping. The study period was from January 2019 to January 2020. Data were collected prospectively, and we considered preoperative, intra-operative, and post-operative variables. We used univariate and multivariate analyses to assess the association. ResultsWe found that salvaged blood greater than 1000 ml (OR 13.78, 95% CI 1.088-17.47, p=0.043), temperature lower than 36°C at entry to the intensive care unit (OR 3.64, 95% CI 1.50-8.82, p= 0.004) and the CBP time greater than 100 minutes (OR 1.012, 95% CI 1.001-1.023, p= 0.036) increased bleeding risk. This association had an AUC of 0.7 (p=0.001, 95% CI 0.595-0.804) and good calibration (H-L 2.44, p = 0.931, R2 0.91). ConclusionOur results showed three factors associated with post-operative bleeding. The perioperative control of these factors could help to reduce the incidence of this complication in patients undergoing cardiac surgery