Abstract: Objective To explore the incidence and risk factors of postoperative delirium (POD) in the elderly patients with different nutritional status who received proximal femoral nail antirotation (PFNA) internal fixation, and to provide basis for targeted intervention. Methods A total of 335 elderly patients were selected from Suqian Hospital of Nanjing Drum Tower Hospital Group who received PFNA internal fixation under general anesthesia. Mini Nutritional Assessment Short-form (MNA-SF) was used to assess the nutritional status before operation, and Confusion Assessment Method (CAM) was used to assess the incidence of POD. Multiple Logistic regression analysis was performed to analyze the influencing factors of the occurrence of POD. Results The incidence rate of POD was 26.23% (48/183)in the elderly patients with normal nutrition, compared with 41.45% (63/152) in those with MNA-SF score of 0-11 (P<0.05). The incidence rate of POD in the elderly patients with MNA-SF score of 0-7 was significantly higher than that in the patients with score of 8-11 (60.78% vs 31.68%, P<0.05). Multivariate Logistic regression analysis showed that age ≥ 75 years, body mass index <20, malnutrition, hypoalbuminemia, general anesthesia time ≥ 120 min, poor postoperative analgesia effect and MMSE score<27 were the risk factors for POD in the elderly patients receiving PFNA internal fixation. Conclusions The incidence rate of POD in the elderly patients undergoing PFNA surgery with malnutrition risk or malnutrition is higher. The patients with poorer nutritional status are more likely to have POD.

Key words: malnutrition, proximal femoral nail antirotation, aged, postoperative delirium, influencing factor