Hemoglobin level, degree of mobilization, and pneumonia are associated with the development of postoperative delirium in cemented hemiarthroplasty after femoral neck fracture

Purpose The aim of this retrospective study was to identify independent prognostic factors for developing a postoperative delirium (POD) in patients suffering from a proximal femoral neck fracture and treated by implantation of a hemiprosthesis. Methods A retrospective study, including patients with hip hemiarthroplasty due to a femoral neck fracture between 2011 and 2020 was performed. Demographic data, preexisting conditions, intra-/postoperative complications, mobilization and laboratory results were extracted from the patients' charts. The different parameters were analyzed comparing patients with and without POD. Results 412 patients, mean age of 81 +/- 9.58 years were included, 66.5% (n = 274) were female, 18.2% (n = 75) of them developed a POD. Significantly higher incidence of POD was associated with older age (p < 0.001), lower level of haemoglobin (p < 0.001), higher post-surgery interleukin 6 (IL 6) level (p = 0.008), higher postoperative level of leukocytes (p = 0.01). Patients with POD received more units of packed red blood cells (PRBC) (p = 0.007). Patients with no mobility limitations pre-operatively developed POD less frequently (p = 0.01), whereas suffering from pneumonia (p = 0.03) or limited mobility postoperatively increased the risk of POD (p < 0.001). Conclusion This study could help to identify patients with a risk for developing POD after a hemiarthroplasty in femoral neck fractures. As a consequence, frequent controls of Hb, IL 6 and leucocytes levels to avoid anemia and infections, as well as the well surgical treatment to guarantee a good postoperative outcome.