Impact of General Anesthesia and Antioxidants on Cognitive, Static and Locomotor Functions During Laparoscopic Cholecystectomy

Abstract

   Aim of the study: to reduce cognitive impairment during laparoscopic cholecystectomy by perioperative administration of drugs with antihypoxic and antioxidant effects under the control of stabilography.   Materials and methods. We studied the effect of general anesthesia and antioxidants on cognitive, static and locomotor functions during laparoscopic cholecystectomy. We studied 90 patients with acute calculous cholecystitis randomized into three experimental groups (n=30, each group). The control group was composed of 24 healthy individuals. Group 1 patients received no antioxidants, group 2 patients received the combination antioxidant drug (sodium fumarate+sodium chloride+potassium chloride+magnesium chloride) in the post-operative period, and group 3 patients received methylethylpyridinol. The patient groups were comparable in sex, age and type of inflammatory and destructive process in the gallbladder. Surgical intervention was performed under endotracheal anesthesia. Premedication with atropine and promedol was given, and anesthesia induction was carried out with propofol, fentanyl and suxamethonium. Sevoflurane, fentanyl andcisatracurium were employed to maintain anesthesia, analgesia and myorelaxation, respectively. The patients were examined before surgery, 24 and 48 hours after surgery. In the groups of patients who received antioxidant therapy, blood sampling for hematological and biochemical examinations was performed 30 min after the administration of antioxidants. Stabilographic studies and MoCA test (Montreal Scale) were performed before antioxidant administration prior to surgery and after surgery, on days 2 and 3.   Results. Neuropsychological testing revealed postoperative cognitive dysfunction on standard therapy which included impaired attention and concentration, executive function, memory, speech, visual constructional skills, abstract thinking, counting, and orientation (21 points on the MoCA scale versus 28–30 points for normal). We found that the pathogenetic factors of cognitive dysfunction included insufficient antioxidant protection, decreased TNF-α and elevated interleukin-18 levels along with an increased level of C-reactive protein in plasma, which manifested as activation of free-radical oxidation processes and reduced antioxidant system and performance of nonspecific resistance. Perioperative use of the combination antioxidant drug and methylethylpyridinol antioxidants reduced the frequency and severity of postoperative cognitive impairment in patients after laparoscopic cholecystectomy.   Conclusion. The most important pathogenetic factors of cognitive dysfunction after laparoscopic cholecystectomy include activation of free-radical oxidation, reduction of antioxidant defense system performance and lack of nonspecific resistance factors. Adding the combination antioxidant drug or methylethylpyridinol to the standard therapy reduces the intensity of radical oxygen species generation, maintains the antioxidant potential, activates production and secretion of nonspecific resistance factors, preventing the development and reducing the severity of cognitive disorders in the perioperative period. Neuropsychological testing and stabilographic examination allow identifying the risk of cognitive disorders in patients after laparoscopic cholecystectomy and provide a rationale for the use of antioxidant therapy for their prevention.