Association between intraoperative hypotension during brain tumor resection and postoperative delirium: A secondary analysis of a randomized controlled trial.

OBJECTIVE: Postoperative delirium is a common complication after neurosurgery. The association between intraoperative hypotension and postoperative delirium in the neurosurgical population is unknown. DESIGN: This is a secondary analysis of a randomized controlled study. SETTING: Adults scheduled for elective craniotomy under general anesthesia were included in 1 study center. PARTICIPANTS: Of 260 patients, a total of 240 participants are included for final analysis after excluding patients without intraoperative blood pressure data. THE PRIMARY OUTCOME MEASURES: The primary outcome was the occurrence of delirium within the first 5 postoperative days, assessed with the Confusion Assessment Method or a 3-minute Diagnostic interview for the Confusion Assessment Method. RESULTS: A total of 240 patients were included (median age, 45 years), and 83(35%) patients experienced postoperative delirium. Curves of lowest mean arterial pressure versus stroke incidence suggested a threshold at 65 mmHg. There was no association between duration below 65 mm Hg and postoperative delirium (odds ratio, 1.01; 95% confidence interval, 0.96, 1.06). The odds ratio for duration below 65 mm Hg for 10 minutes was 1.03 (95% confidence interval, 0.97, 1.09) adjusted by history of hypertension, age > 45 yr, tumor volume, tumor type of glioma, preoperative Mini-Mental State Examination (MMSE) >26, and dexmedetomidine infusion which were all indicated the independent risk factors for delirium. CONCLUSIONS: The current results could not indicate intraoperative hypotension of mean arterial pressure lower than 65 mmHg associated with delirium after frontotemporal brain tumor resection. TRIAL REGISTRATION: ClinicalTrials.gov NCT04674241.