Introduction: Postoperative cognitive dysfunction (POCD), which tends to happen soon after surgery, is a problem that can persist for several weeks or months. Sometimes it may be permanent. POCD is a serious complication and it is reported that POCD increases rates of mortality. Living liver donor hepatectomy is performed under general anesthesia and takes a long time. Microembolies cause ischemic tissue damage that may occur during manipulation of the liver which may lead to the development of POCD. The aim of the study was to investigate the levels of preoperative and postoperative cognitive function in living liver donors.

Materials and Methods: After approval by the ethics committee of Inonu University and written informed patient consent, 102 living liver donors were enrolled in this prospective study. Preoperatively Standardized Mini-Mental test, Stroop test, Beck Depression inventory and Trail Making tests were performed by a psychiatrist. In the operation room, electrocardiogram, arterial oxygen saturation, noninvasive blood pressure monitoring were obtained in all patients. BIS monitor was used to assess the depth of anesthesia. The same anesthetic technique was performed in all patients. Mean arterial pressure (MAP), heart rate, SpO2 and bispectral index values were recorded during the operation. Surgical technique (right/left lobe), pringle maneuver application time, amount of bleeding and blood replacement, the duration of surgery and anesthesia, hypotensive episodes (MAP<65 mmHg) were recorded. Postoperatively, 0.05 mg/kg morphine was given intravenously for analgesia. The patients were extubated at the end of the surgery. 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 recipients’ prognosis were recorded.

Results: Postoperative Trail Making A test score significantly decreased compared with the preoperative period (p<0.05). Number of errors of Postoperative Trail Making B test increased significantly than 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 incorrect answers, while telling color of color words in the preoperative period were significantly higher than post-operative period (p =0.044). In the postoperative period, infection occured in 19 donors, bleeding in two, prolonged hyperbilirubinemia in 7 donors. Two donors reexplored postoperatively.

Conclusions: In this study, POCD was not observed based on Standardized Mini Mental test and Trail Making tests. Stroop black/white and color words reading time significantly prolonged after a week. This suggests, there could be a little bit frontal lobe impairment in donors and could result attentional problems in the postoperative period. However, we believe further studies are needed to investigate whether these problems are permanent and clinically significant.