The levels of postoperative cognitive function in living liver donors

Backround and aim: Postoperative cognitive dysfunction (POCD), which tends to happen soon after surgery, is a problem can persist for several weeks or months, sometimes it may be permanent. Neuropsychological performance can be assessed by neuropsychological tests. POCD is a serious complication and it is reported that POCD increases rates of mortality. Live donor liver transplantation surgery is performed under general anesthesia and taken a long time. Microembolies cause ischemic tissue damage that may occur during manipulation of the liver may lead to the development of POCD. The aim of the study is measuring the levels of preoperative and postoperative cognitive function of living donor liver transplantation donors. Materials and Methods: This study received ethics committee approval and patient consent, then the donor liver transplantation was performed in 102 cases. Preoperatively to determine the level of the patients basal cognitif function, Standardized Mini-Mental test, Stroop test, Beck Depression inventory and Trail Making tests were performed by a psychiatrist. Electrocardiogram, arterial oxygen saturation, noninvasive blood pressure monitoring were obtained in all patients in the operation room. BIS monitor was used to assess the depth of anesthesia. Basal hemodynamic values of cases were recorded. In all patients, anesthesia was standardized with lidocaine, fentanyl and thiopental. Patients were intubated after muscle relaxation provided with vecuronium. Anesthesia was maintained with isoflurane in 40 % oxygen-air mixture, an infusion of remifentanil and cisatracurium. Invasive arterial blood pressure was 42 monitored in the left radial artery. In patients where more than 20 % of intraoperative bleeding, internal jugular vein central venous catheter was inserted. The patients during the operation mean arterial pressure, heart rate, SpO2 and BIS values were recorded. Surgical technique (right/left lobe), pringle maneuver applied time, amount of bleeding and blood replacement, the duration of surgery and anesthesia, mean arterial pressure, hypotensive episodes falls below 65 mmHg were recorded. Postoperatively, 0.05 mg/kg iv. morphine was given for analgesia. The patients were extubated at the end of the surgery after antagonization of muscle relaxant effect. The patients were observed in the recovery unit for half an hour and then sent to the surgical intensive care unit. Preoperative tests were repeated one week after surgery. Postoperative complications and the recipient's prognosis were recorded. Results: In the postoperative period, infection was occured in 19 donors, bleeding in two, prolonged hyperbilirubinemia were developed in 7 donors. Two donors were eksplored again. Postoperative Trail Making A test of donors compared with the preoperative period was significantly lower (p < 0.05). Postoperative Trail Making B test number of errors increased significantly compared to the preoperative level (p <0.05). Postoperative Stroop black/white and color words reading time significantly prolonged compared with the preoperative period (p < 0.001). The time difference between telling the color of color words and reading the color words was longer in the preoperative period than postoperative period (p = 0.016). The number of incorrects, while telling color of color words in the preoperative period were significantly higher than post-operative period (p = 0.044). Donors Beck Depression inventory and Standardized Mini Mental test scores were not different preoperatively and postoperatively. Conclusion: The biggest concern for the safety of living donor liver transplantation is postoperative complications that effect a donor morbidity and mortality. In this study we investigate the level of cognitive function in donors living donor liver transplantation based on Standardized Mini Mental test and Trail Making tests. POCD was not observed, but in Stroop test 1 and 3, was prolonged after a week postoperatively compared with preoperative period. However, further studies are 43 needed to investigate the clinical significance of this opinion. Key words: Post-operative Cognitive Dysfunction, Standardized Mini Mental test, Bispectral Index, Donor hepatectomy, Stroop test, Trail Making test, Beck Depression inventory.