Cardioand neuroprotection with volatile anesthetics in cardiac surgery

Abstract

The researcher's opinions about myocardial and brain anesthetic preconditioning efficiency are yet contradictive. In addition, the anesthetic neuroprotection phenomenon is poorly investigated. In this study the authors attempted to evaluate the efficiency of myocardial and central nervous system (CNS) protection by using a modified method of volatile induction and maintenance of anesthesia (VIMA) based on pulse-like sevoflurane dosing that excludes propofol usage. Ninety CABG patients aged 45-75 years were included in the study group (VIMA) and underwent volatile induction with sevoflurane and anesthetic preconditioning (2 MAC) for 10 min before aortic cross-clamping, with ataralgesia used during CPB. The control group patients (TIVA) received propofol and fentanyl, no inhalation anesthetics were applied. Preoperative concentrations of NTpro-BNP were comparable. There was no significant rise of NTpro-BNP concentration in the VIMA group during the postoperative period. In the TIVA group NTpro-BNP concentrations were 3.8 and 4.8 times as much as the baseline values at 24 and 48 postoperative hours respectively (р<0.05). 17 patients in the VIMA group needed dopamine infusion during 24 postoperative hours, this number was 1.7 times less than that in the TIVA group (23 patients) (р<0.05). VIMA patients had 2-fold lower troponin T concentration in 24 hours after surgery (р<0.01). Significant differences in protein S100B concentrations were observed only during the postoperative period. No significant differences in cognitive functions of the patients from both groups were identified before surgery. On postoperative day 2 MMSE scale count was significantly lower in TIVA patients (20.843.73) in comparison with VI-MA patients (23.364.34) (р<0.05). Thus, the modified VIMA technique with sevoflurane has a greater neuroprotective potential during CABG with CPB and provides better preservation of myocardium structural integrity and cardiac performance than fentanyl/4propofol-based TIVA would do.