Influence of low-opioid anesthesia in cardiac surgery on dynamics of pro-inflammatory interleukin-6

Introduction
With coronary artery bypass grafting, patients are subjected to additional risk caused by both surgical treatment itself and pathophysiological changes in homeostasis, provoked by the action of anesthetics and cardiopulmonary bypass.

Material and methods
The study involved 60 patients, who had been subjected to coronary artery bypass grafting with cardiopulmonary bypass. All patients were divided into two groups: group I (30 patients) – low-opioid scheme of anesthesia and group II (30 patients) – standard scheme of anesthetic management. Blood interleukin-6 (IL-6) was identified before and after cardiopulmonary bypass using an ELISA test.

Results
Having compared IL-6 values between study groups after completion of cardiopulmonary bypass, it was established that IL-6 levels were 27.51% (p = 0.001) lower in patients of group I compared with the results of patients in group II. Patients in the first group had a significantly shorter time of mechanical ventilation compared to group II (2.1 ±0.7 hours vs. 3.9 ±0.9 hours, p = 0.021). Low cardiac output syndrome was significantly less frequently reported in patients of group I (10.0% vs. 33.3%, p = 0.028). In addition, patients in group I had a significantly shorter time of intensive care unit (ICU) stay (2.5 ±0.7 days vs. 3.5 ±1.0 days, p = 0.044).

Conclusions
Application of multimodal low-opioid anesthesia was associated with significantly lower IL-6 at the end of surgery, shorter mechanical ventilation duration, less frequent low cardiac output syndrome and need for catecholamines, and shorter ICU stays.