Postoperative Delirium in Patients Receiving Hip Bipolar Hemiarthroplasty for Displaced Femoral Neck Fractures: The Risk Factors and Further Clinical Outcomes

Background: Postoperative delirium in patients who have hip fractures may lead to poor outcomes. This study aimed to determine perioperative risk factors and clinical outcomes of postoperative delirium in patients undergoing hip bipolar hemiarthroplasty for displaced femoral neck fractures. Methods: Among 1,353 patients who underwent hemiarthroplasty at our institution during 2013-2021, we identified 78 patients with postoperative delirium diagnosed with the confusion assessment method. The mean delirium duration was 28 hours (range: 15-520). We also included 1:2 sex- and age-matched patients who did not have postoperative delirium after the same surgery as a matching cohort for comparison. Patient comorbidities, perioperative data, delirium occurrence, and outcomes were collected for analyses. Results: A Charlson Comorbidity Index (CCI) score ≥6 (odds ratio (OR): 2.08, P = .017), nighttime surgery (OR: 3.47, p =<.001), surgical delays (OR: 1.01, P = .012), preoperative anemia (OR: 2.1, P = .012), and blood transfusions (OR: 2.47, P = .01) may increase the risk of postoperative delirium. The presentation of delirium was associated with sepsis (OR: 3.77, P = .04), longer hospital stays (P < .001), higher 1-year mortality (OR: 3.97, P = .002), and overall mortality (OR: 2.1, P = .02). Conclusion: Postoperative delirium predicted poor outcomes. Our results emphasized the importance of early identification of patients at risk and optimization of the medical conditions before and after surgery.