[Risk factors associated with delirium for patients with hip fracture under the orthogeriatric unit mode]

Objective: To explore postoperative delirium (POD)risk factors for geriatric patients who suffered hip fracture under the care of orthogeriatric unit mode. Methods: Patients aged 65 years or older, who were admitted to the orthogeriatric unit in Beijing Jishuitan Hospital from April to October 2017 for hip fracture surgery, were eligible for this prospective cohort study. After univariable analysis, significant risk factors associated with POD were further evaluated with multivariable analysis, to establish independent risk factors associated with POD. Results: A total of 203 patients with an average age of 80(65-96)years were enrolled in the study. The overall incidence of POD was 9.4%(19/203)in which hyperactive and hypoactive type accounting for 84.2%(16/19)and 15.8%(3/19), respectively. Significant difference was found between POD and non-POD groups in patients' age (P=0.003), albumin(P=0.006), TSH(P=0.018), PaCO(2) level(P=0.003), visual analogue scale (VAS )both at rest (P=0.013)and movement(P=0.010) on post-operative day 1.The further Logistic stepwise regression analysis showed that significant differences existed between groups in age(P=0.027), albumin(P=0.003), PaCO(2)(P=0.014)and VAS at rest(P=0.002). Conclusion: The independent risk factors of POD in geriatric patients undergoing hip fracture under the orthogeriatric unit mode include patients' age, pre-operative albumin as well as PaCO(2) level and post-operative VAS at rest.