[Risk factors for delirium of elderly patients undergoing hip fracture operation]

To explore the causes for delirium of elderly patients after hip fracture operation.

A total of 68 cases of delirium were selected from 458 patients aged over 65 years undergoing hip fracture operation via spinal anesthesia from 2009 to 2011. There were 26 males and 42 females with an average age of 72.9 (66-98) years. Their clinical features, such as gender, operative duration, blood loss volume, saturation of arterial oxygen, were observed. After single factor risk analysis, multiple factor analysis was performed by binary Logistic regression.

Delirium occurred at certain timepoints during the first postoperative days. The incidence of delirium was 14.9%. The Logistic stepwise regression analysis showed that significant differences existed between delirium and non-delirium in age (P = 0.042), operative duration (P = 0.042), blood loss volume (P = 0.027), hypoxemia (P = 0.019) and preoperative comorbidity (P = 0.029).

The independent risk factors for postoperative delirium include age, operative duration, blood loss volume, preoperative comorbidity and hypoxemia.