Postoperative psychomotor dysfunction is called postoperative cognitive dysfunction, and the incidence of postoperative complications is high, especially in elderly patients undergoing major surgery. This complication; It can be attributed to the anesthetic agents used, their doses, and the duration of the surgery. Although SARS-CoV-2 virus causes an infection called Covid-19 that mainly affects the respiratory tract, data have been obtained that it can enter the nasal mucosa, reach the central nervous system via olfactory fibers or hematogenous way, and infect endothelial cells and neurons. The immune system is activated due to endothelial cell damage, vascular permeability increases, and the risk of thrombosis occurs. Cerebral hypoperfusion promotes Lewy body development, especially by increasing amyloid plaque formation and inducing serine phosphorylation. The formation of these plaques, which are responsible for the development of Alzheimer's and Dementia, suggests that Covid-19 may have long-term neurological complications. In our study, we included patients who were scheduled for cholecystectomy, who had and did not have covid-19 infection. Covid-19 infection (Group 1), no previous (Group 2), COVID-19 and pre-induction low-dose intravenous ketamine (0.5 mg/kg) administered (Group 3), non-covid-19 and pre-induction low-dose intravenous ketamine We aimed to evaluate and compare postoperative cognitive functions in patients (Group 4) administered (0.5 mg/kg). Ketamine is a sedative, hypnotic and analgesic agent and has an effective role in balanced anesthesia. In addition, its use reduces the need for the use of other anesthetic agents. The use of ketamine in normal doses causes a decrease in brain and cognitive functions; The use of sub-anesthetic doses before induction has positive effects on recovery and cognitive functions. Depth of anesthesia with bispectral index continuously before and throughout the operation; The lowest and highest values were recorded by regional cerebral oximetry (rSO2) measurement. Cognitive tests were performed 1 day before the operation, at the 12th hour and 30 days after the operation. MMT (mini mental test), Verbal Fluency Test (verbal fluency test), Clock Drawing Test (clock drawing test) Aldrete recovery scores were evaluated at the 2nd and 5th minutes after extubation. The study included 160 patients, 35-55 young and middle-aged, ASA I and II. Patients who underwent emergency surgery, had malignancy, and had a known chronic disease were excluded from the study.

Postoperative psychomotor dysfunction is called postoperative cognitive dysfunction, and the incidence of postoperative complications is high, especially in elderly patients undergoing major surgery. This complication; It can be attributed to the anesthetic agents used, their doses, and the duration of the surgery. Although SARS-CoV-2 virus causes an infection called Covid-19 that mainly affects the respiratory tract, data have been obtained that it can enter the nasal mucosa, reach the central nervous system via olfactory fibers or hematogenous way, and infect endothelial cells and neurons. The immune system is activated due to endothelial cell damage, vascular permeability increases, and the risk of thrombosis occurs. Cerebral hypoperfusion promotes Lewy body development, especially by increasing amyloid plaque formation and inducing serine phosphorylation. The formation of these plaques, which are responsible for the development of Alzheimer's and Dementia, suggests that Covid-19 may have long-term neurological complications. In our study, we included patients who were scheduled for cholecystectomy, who had and did not have covid-19 infection. Covid-19 infection (Group 1), no previous (Group 2), COVID-19 and pre-induction low-dose intravenous ketamine (0.5 mg/kg) administered (Group 3), non-covid-19 and pre-induction low-dose intravenous ketamine We aimed to evaluate and compare postoperative cognitive functions in patients (Group 4) administered (0.5 mg/kg). Ketamine is a sedative, hypnotic and analgesic agent and has an effective role in balanced anesthesia. In addition, its use reduces the need for the use of other anesthetic agents. The use of ketamine in normal doses causes a decrease in brain and cognitive functions; The use of sub-anesthetic doses before induction has positive effects on recovery and cognitive functions. Depth of anesthesia with bispectral index continuously before and throughout the operation; The lowest and highest values were recorded by regional cerebral oximetry (rSO2) measurement. Cognitive tests were performed 1 day before the operation, at the 12th hour and 30 days after the operation. MMT (mini mental test), Verbal Fluency Test (verbal fluency test), Clock Drawing Test (clock drawing test) Aldrete recovery scores were evaluated at the 2nd and 5th minutes after extubation. The study included 160 patients, 35-55 young and middle-aged, ASA I and II. Patients who underwent emergency surgery, had malignancy, and had a known chronic disease were excluded from the study.

Inclusion Criteria:

• Patients aged 35-55 years ASA 1, 2 group Patients scheduled for cholecystectomy

Exclusion criteria:

Patient's refusal to participate in the study Those with malignancy Patients scheduled for emergency surgery

patients with and without covid 19