Opioid-free Anesthesia and Postoperative Delirium

Postoperative delirium (POD) is a common acute and transient form of brain dysfunction in elderly patients following surgery that can lead to serious adverse clinical outcomes and even death. Although existing studies have preliminarily investigated the effects of opioid-free anaesthesia (OFA) on POD, high-quality evidence on these effects for elderly patients undergoing gastrointestinal surgery remains limited. This study aims to investigate the effects of OFA on the development of POD in elderly patients following gastrointestinal surgery. This single-centre, prospective, randomized controlled trial will be conducted at the First Affiliated Hospital of Shandong First Medical University, China. A total of 654 patients aged 65 years or older who are scheduled for elective gastrointestinal surgery will be randomly allocated to receive either opioid-free anaesthesia (OFA; dexmedetomidine, esmolol, and esketamine) or conventional opioid-based anaesthesia (OBA). The primary outcome is the incidence of POD 7 days after surgery. The secondary outcomes are all-cause mortality within 30 days after surgery, intraoperative haemodynamic changes, the 15-item quality of recovery (QoR-15) scores at 24 h, 48 h, and 72 h after surgery, complications during postoperative hospitalization, pain numerical rating scale (NRS) score at 72 h after surgery, incidence of nausea and vomiting at 72 h after surgery, morphine milligram equivalent for analgesics at 72 h after surgery, duration of anaesthesia (from induction to discontinuation), duration of surgery (from skin incision to the last suture), duration of post-anaesthesia care unit (PACU) stay, and length of hospital stay. The results of this study may shed light on the effects of OFA on POD in elderly patients undergoing gastrointestinal surgery. The study is designed on the basis of the following key hypothesis: the use of opioid drugs for anaesthesia may increase the risk of POD through mechanisms such as blood-brain barrier destruction, neuroinflammatory responses, and central nervous system depression. Through the single-centre and prospective design of this randomized controlled trial, this study will directly analyse differences in the effects of OFA and conventional OBA on the incidence of POD, haemodynamic stability and long-term cognitive function in elderly patients.

Sex

All

Minimum age

65 Years

Inclusion Criteria:

1. Patients who plan to undergo elective gastrointestinal surgery under general anaesthesia
2. Age ≥65 years
3. American Society of Anaesthesiologists (ASA) grade I-III
4. Body mass index (BMI) of 18.0-30.0 kg/m²
5. Frailty: mFI ≥ 0.27
6. Signed informed consent

Exclusion Criteria:

1. Patients undergoing emergency surgery
2. Patients with language disorders or severe hearing or vision impairment that prevent communication
3. Patients with a history of neurological and psychiatric disorders, including Alzheimer's disease (AD), other types of dementia, stroke, and psychosis
4. Patients with long-term use of psychotropic medications (such as clozapine, risperidone, olanzapine, haloperidol, and chlorpromazine)
5. Patients who have undergone cardiac surgery or craniocerebral surgery within the past year
6. Patients who have participated in other relevant clinical trials within the past 3 months
7. Patients with preoperative cognitive impairment (Telephone Interview for Cognitive Status-modified (TICS-m) score ≤ 27), as determined via the TICS-M test
8. Each patient can be included only once, regardless of whether the reason for the second surgery is related to the primary cause
9. Let me know if you need this in a different bullet style (e.g., asterisks) or with indentation adjustments.

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