Effect of noise isolation on postoperative delirium in elderly patients undergoing hip surgery: protocol for a randomised controlled trial.

introductionPostoperative delirium (POD) is a frequent complication in elderly surgical patients, leading to increased morbidity and mortality. Previous studies have shown that noise isolation is associated with a reduced incidence of delirium in the intensive care unit (ICU). This trial aims to evaluate the impact of noise isolation using noise-cancelling headphones on the incidence of POD in elderly patients undergoing hip surgery. METHODS AND ANALYSIS: In this randomised controlled trial, a total of 320 elderly patients will be randomised to a noise isolation group or a control group, in a 1:1 ratio and stratified by age (65‒80 years or >80 years), type of surgery (fracture or non-fracture) and planned ICU admission (yes or no). For patients in the noise isolation group, noise-cancelling headphones will be used throughout anaesthesia and in the postoperative care unit or ICU. Patients in the control group will be routinely managed and exposed to the clinical environment. The primary outcome is the incidence of POD during 0‒7 days after surgery or before hospital discharge, assessed using the 3 min Confusion Assessment Method or the Confusion Assessment Method for the Intensive Care Unit. The secondary outcomes include postoperative pain at 6, 24 and 48 hours after surgery; sleep quality on the first and second nights after surgery; incidence of nausea and vomiting within 48 hours postoperatively; and cognitive function and mortality at 30 days after surgery. ETHICS AND DISSEMINATION: The trial was approved by the Ethics Committee of the First Affiliated Hospital of Soochow University (Approval No. 2024-054). The results of this trial will be submitted for peer review and publication in a scientific journal. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR2400082211).