Postoperative recovery and delirium incidence in geriatric patients undergoing colorectal surgery under low-flow anesthesia and normal-flow anesthesia

Introduction and Objective: In this study; It was aimed to evaluate the effects of low flow anesthesia method on recovery and postoperative delirium development in geriatric patients undergoing gastrointestinal surgery in the operating room of Dicle University Hospital. Materials and Methods: Fifty general surgery patients over the age of 50 undergoing elective gastrointestinal surgery were included in this study. Exclusion criteria: - Those with a history of dementia, sleep disorder, psychosis - Those with a history of opioid, alcohol and substance abuse - Those with cardiomyopathy, liver and kidney failure and cerebrovascular disease, - Those who had surgery in the previous 6 months, - Those with hearing and vision impairments, - bleeding disorder, those using drugs that affect the coagulation system, - hypoalbuminemia (<3gr / dl), - Those with preoperative low hematocrit (<30) - drug allergy - Those with immobility and malnutrition were excluded from the study. Informed consent was obtained from the patient or patient relatives for the study. Standard anesthesia monitoring was provided for all patients. Half (25) of the patients were randomly selected and normal flow anesthesia was applied. Low flow anesthesia was applied to the other half (25). The Richmond Agitation and Sedation score was measured at 5/15/60 minutes postoperatively in the patients who were taken to the recovery room after awakening. Patients were grouped as hypoactive (RASS ≤ -2), normal (RASS 0 or -1), hyperactive (RASS ≥ +1) according to their RASS score. Abnormal RASS scores were accepted as ≤-2 and ≥1. The postoperative RASS scores of the patients were compared according to the duration of surgery. Results: Patients with RASS scores checked at the postoperative 60th minute were considered to be in postoperative delirium, and the distribution of these patients according to the groups was evaluated. Postoperative delirium incidence was found to be 28% in patients in the normal flow anesthesia group. Postoperative delirium incidence was 8% in patients undergoing low flow anesthesia. In our study, no significant relationship was found between gender and postoperative delirium. However, a significant relationship was found between advanced age and delirium (p <0.05). In our study, we did not observe a significant difference between the duration of surgery, recovery and postoperative delirium incidence regardless of the anesthesia method applied (p> 0.05). Conclusion: As a result, we found that the low-flow anesthesia method applied under modern and efficient conditions of the anesthesia workstation not only provided economic, environmental and employee safety, but also reduced the delirium incidence in the recovery period of the geriatric patient from anesthesia. While preparing for this issue, we came across a small number of studies, especially on low flow and delirium. This shows that there is a need for studies with larger series on this subject. Keywords: Low Flow Anesthesia, Postoperative Delirium, Delirium, Richmond Agitation-Sedation Scale, General Anesthesia.