Association of preoperative frailty with postoperative delirium after elective brain tumor resection: Retrospective analysis of a prospective cohort.

Background: Preoperative frailty is associated with poor outcomes in major surgery. Postoperative delirium is common after neurosurgery. To date, the association of preoperative frailty with postoperative delirium after neurosurgery has not been established. We aimed to determine the association between preoperative frailty and postoperative delirium in patients undergoing elective brain tumor resection.

Methods: We retrospectively analyzed the data of a prospective cohort, consecutively enrolling adult patients admitted to the intensive care unit after elective craniotomy for brain tumor resection under general anesthesia in a tertiary hospital in China from March 1, 2017 to February 2, 2018. Preoperative frailty was evaluated using the modified frailty index. The primary outcome was postoperative delirium, assessed using the Confusion Assessment Method for the Intensive Care Unit. Univariate and multivariable regression analyses were performed to examine the association.

Results: 659 patients met inclusion criteria for our analysis. There were 398 (60.4%) non-frail (modified frailty index = 0), 237 (36.0%) pre-frail (modified frailty index = 1-2), and 24 (3.6%) frail (modified frailty index ≥ 3) patients. Of these, 124 (18.8%) developed postoperative delirium. In adjusted analyses, frailty was independently associated with postoperative delirium (odds ratio 1.7, 95% confidence interval 1.0-2.7, P = .032). Frail patients had longer length of hospital stay and higher total costs than non-frail patients.

Conclusion: Preoperative frailty is associated with postoperative delirium, length of hospital stay, and total costs in patients undergoing elective brain tumor resection. Preoperative frailty assessment and appropriate management strategies should be involved in the perioperative management of postoperative delirium.