Treatment of postoperative delirium with continuous theta burst stimulation: study protocol for a randomised controlled trial

Abstract

Introduction: Postoperative delirium is one of the most common postoperative complications among elderly patients (65 years old or older). However, there are no effective treatments for this condition. Recent research suggests that continuous theta burst stimulation (cTBS), a non-invasive brain stimulation, can reduce pain level, improve cognitive function and affective symptoms in multiple diseases or dysfunctions, including anxiety disorders, major depressive disorder, sleep disorders and pain. But the potential benefits of cTBS in reducing postoperative delirium have not been investigated. Therefore, we propose determining whether cTBS can prevent and/or treat postoperative delirium in senior patients.

Methods and analysis: The study will be a double-blind, randomised controlled trial. Participants (65 years old or older) undergoing scheduled orthopaedic surgery (≥2 hours, general anaesthesia) will be randomised to receive either cTBS or sham stimulation with a focal figure-of-eight coil over the right dorsolateral prefrontal cortex at 80% of the resting motor threshold. Every patient will receive 2-3 sets of stimulations during postoperative days (40 s per session, 3 sessions per set, 1 set per day). Participants will be assessed twice daily by a research assistant blinded to allocation. The primary outcome will be the incidence of postoperative delirium measured by the Confusion Assessment Method on postoperative days 1, 2 and 3. The secondary outcomes will be the severity and duration of postoperative delirium, cognitive function, pain, sleep quality, activities of daily living, length of hospital stay, discharge-to-facility or home, and rate of complication and mortality during the hospital stay.

Ethics and dissemination: Ethical approval has been obtained from the ethics committee of Shanghai 10th People's Hospital. The principal investigator will submit a research progress report to the ethics committee regularly. All participants will provide written informed consent. Study results will be published in a peer-reviewed journal.

Trial registration number: NCT04661904.

Keywords: clinical trials; delirium & cognitive disorders; psychiatry.

Conflict of interest statement

Competing interests: None declared.

© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

Figures

Figure 1

Study flow chart. The present study is a randomised controlled trial. The enrolled participants will be randomised equally into two groups. After surgery, each participant will be allocated to receive sham or active stimulation. the incidence and severity of postoperative delirium following cTBS or sham stimulation will be recorded and analysed to determine potential differences between the two cohorts. cTBS, continuous theta burst stimulation; ISI, intersession interval; RMT, resting motor threshold.

Figure 2

Study schedule. Description of the study protocol. ADL, activities of daily living; CAM, Confusion Assessment Method; CAM-S, Confusion Assessment Method based-Scoring System for Delirium Severity; DSI, Delirium Symptom Interview; ICF, Informed Consent Form; MMSE, Mini-Mental State Examination; VAS, Visual Analogue Scale.