Cardiac surgery with cardiopulmonary bypass (CPB) is associated with a systemic inflammatory response (SIR) that furthers peri-operative life-threatening complications and multiple organ dysfunction syndromes (MODS). These features can prolong cardiac intensive care units (CICU) and hospital stay.Objectives
This study was to compare the level of benefit among modified Sequential Organ Failure Assessment (SOFA), interleukin (IL)-6, and IL-10 levels for evaluation of the severity of SIR during peri-operative period in patients undergoing cardiac surgery with CPB which is reflected by prolonged CICU stay (> 42 hours).Methods
This prospective observational design study was approved by Khon Kaen University Human Ethics Committee (HE531033). Thirty four consecutive adult patients who underwent elective cardiac surgery with CPB were enrolled between February and June, 2010. Plasma concentration of IL-6, IL-10 levels were collected and measured sequentially at 0, 0.5, 4, 12, and 24 hours after CPB. Data for modified SOFA score, including peri-operative outcomes and complications, were collected at the same time-points. In addition, the receiver operating characteristics (ROC) analysis was used to determine the usefulness of these three indexes as predictors of prolonged CICU stay. P < 0.050 was considered statistically significant.Results
A total of 34 patients were admitted to CICU after cardiac surgery. Sixteen of these, aged 61.1 ± 3.1 years, required prolonged CICU stay and had longer mechanical ventilation than the non-prolonged CICU group (P < 0.050). The mean of all 3 prognostic models in patients with prolonged CICU stay were significantly higher at 4 hours, and were still significantly increased after 24 hours than for those with non-prolonged CICU, except IL-10 which declined to near normal levels (P < 0.050). Correlation of IL-6 and modified SOFA score were significantly higher than correlation of IL-10 and modified SOFA (r2= 0.743, P < 0.0001, and r2= 0.632, P < 0.0001, respectively). Calculation of area under ROC curve (AUC) for 3 prognostic models at 4 hours after CPB to predict prolonged CICU stay provided comparable values (0.743 for IL-6 levels, 0.847 for IL-10 levels, and 0.847 for modified SOFA score) with highest AUC for modified SOFA score.Conclusions
All 3 prognostic models at 4 hours after CPB can reasonably predict the severity of SIR which is reflected by prolonged CICU stay. The modified SOFA score is the most simple yet with highest AUC.