Objectives: Postoperative organ dysfunction is common after cardiac surgery, particularly when cardiopulmonary bypass is used. The Sequential Organ Failure Assessment (SOFA) score is validated to predict morbidity and mortality in cardiac surgery. However, the impact of cardiopulmonary bypass duration on postoperative SOFA remains unclear.
Methods: Retrospective study. Categorical values are presented as percentages. The comparison of SOFA groups utilized the Kruskal-Wallis chi-squared test, complemented by ad-hoc Dunn’s test with Bonferroni correction. Multinomial logistics regressions were employed to evaluate the relationship between cardiopulmonary bypass time and SOFA.
Results: 1032 patients were included. Cardiopulmonary bypass time was independently associated with higher postoperative SOFA scores at 24 h. Cardiopulmonary bypass time was significantly higher in patients with SOFA 4-5 (**P = 0.0022) or higher (***P < 0.001) when compared to SOFA 0-1. The percentage of patients with no/mild dysfunction decreased with longer periods of cardiopulmonary bypass, down to 0% for cardiopulmonary bypass time >180min (50% of the patients with >180min of cardiopulmonary bypass presented SOFA ≥ 10). The same trend is observed for each of the SOFA variables, with higher impact in the cardiovascular and renal systems. Severe dysfunction occurs especially >200min of cardiopulmonary bypass (cardiovascular system >100min; other systems mainly >200 min).
Conclusions: Cardiopulmonary bypass time may predict the probability of postoperative SOFA categories. Patients with extended cardiopulmonary bypass durations exhibited higher SOFA scores (overall and for each variable) at 24 h, with higher proportion of moderate and severe dysfunction with increasing times of cardiopulmonary bypass.
