Comparison of the effects of different multimodal anesthesia techniques on patient outcomes in patients undergoing total knee arthroplasty under regional anesthesia

Comparison of the Effects of Different Multimodal Anesthesia Techniques on Patient Outcomes in Patients Undergoing Total Knee Arthroplasty Under Regional Anesthesia Objective: This study aimed to evaluate postoperative pain, functional outcomes, and complications in patients undergoing total knee arthroplasty (TKA) under different regional anesthesia techniques. Materials and Methods: This retrospective study was conducted at Çukurova University Faculty of Medicine Hospital. Patients who underwent total knee arthroplasty under regional anesthesia between 2020 and 2024 were included. A total of 80 ASA I-III patients undergoing unilateral TKA were enrolled and divided into two groups. Patients who received continuous epidural analgesia (CEA) were assigned to "Group 1," while those who received intrathecal morphine combined with adductor canal block (ITM + ACB) were designated as "Group 2." Patient charts that met the inclusion criteria were reviewed, and data were recorded using a standardized data collection form. Preoperative variables included demographic characteristics, ASA score, Charlson Comorbidity Index, Revised Cardiac Risk Index, comorbidities, functional capacity, and complete blood count. Intraoperative parameters such as duration of surgery, blood pressure, heart rate, total volume and type of intravenous fluids, need for sedation, and dosage of tranexamic acid (if administered) were recorded. Postoperative data included blood pressure and heart rate during the first 24 hours, VAS scores, nausea-vomiting, Bromage score, total amount of patient-controlled analgesia (if used), need for rescue analgesia, postoperative blood count, time to mobilization, complications, Clavien-Dindo classification, reoperation requirement, development of cognitive dysfunction, RASS score, motor strength, range of motion, fall incidence, intensive care unit (ICU) requirement, and length of hospital stay. Post discharge outcomes included hospital readmission, mobilization status, range of motion, morbidity, and mortality. Results: The demographic and intraoperative characteristics of the 80 patients who met the inclusion criteria were comparable between groups. In the first 24 postoperative hours, VAS scores after the first hour were significantly lower in Group 1, with reduced additional analgesic requirements and improved joint range of motion. While vital signs and overall complication rates were similar between groups, the incidence of falls was higher in Group 2. Both techniques were deemed safe; however, continuous epidural analgesia was found to be superior in terms of postoperative pain control and functional outcomes. Conclusion: Continuous epidural analgesia was more effective than the combination of intrathecal morphine and adductor canal block in managing postoperative pain, reducing analgesic requirements, and preserving joint mobility in patients undergoing TKA under regional anesthesia. Although both methods are considered safe, clinical practice should be individualized based on patient-specific factors. Keywords: Total knee arthroplasty, adductor canal block, intrathecal morphine, epidural PCA