Evaluation of a Hospital Program to Prevent Postoperative Delirium in Older Patients

EvaDel is a prospective, single-center, longitudinal implementation study evaluating a multicomponent program for the prevention of postoperative delirium in patients aged 65 years and older undergoing inpatient surgery at the University Medical Center Hamburg-Eppendorf.

The program includes preoperative assessment of delirium-related risk factors, including cognitive impairment, frailty, and malnutrition. Patients are assigned to a low-, intermediate-, or high-risk category. Depending on the individual risk profile, preventive measures may include patient and family education, support with orientation, adequate hydration and nutrition, early mobilization, preservation of the sleep-wake cycle, use of glasses and hearing aids, avoidance of unnecessary room transfers, and reduction of potentially deliriogenic medication. A specialized delirium team supports patients and clinical staff.

All participants receive care according to the prevention processes established at the time of treatment. No separate control group is planned. As the program is implemented gradually in routine clinical practice, outcomes will be analyzed in relation to time since implementation began and to the documented degree of implementation.

Data are collected from medical records and standardized assessments before surgery, during the postoperative hospital stay, at discharge, and during follow-up up to three months after surgery. Assessments include postoperative delirium, cognitive function, frailty, nutritional status, functional independence, complications, and patient experience.

The primary analysis will examine whether postoperative delirium decreases with increasing implementation of the prevention program. Secondary analyses will evaluate cognitive, functional, and clinical outcomes, feasibility, and adherence to the individual prevention measures. Regression models will account for relevant baseline and perioperative risk factors. Exploratory analyses will also be performed within the predefined delirium risk groups.

The study hypothesis is that a higher degree of implementation will be associated with fewer postoperative delirium events and better postoperative cognitive, functional, and clinical outcomes.

• Multicomponent delirium prevention program (Behavioral): * Preoperative screening for cognitive impairment, frailty, and malnutrition * Risk stratification into low-, intermediate-, or high-delirium-risk groups * Patient and family education about postoperative delirium and preventive measures * Individualized measures to support orientation, hydration, nutrition, mobility, and sleep-wake regulation * Provision of glasses and hearing aids when needed * Avoidance of unnecessary room transfers and potentially deliriogenic medications, where clinically feasible * Postoperative delirium screening during the hospital stay * Support by a specialized delirium team * Staff education on delirium prevention, recognition, and management * Stepwise implementation, with the delivered intervention components documented for each participant

Primary outcomes

• Incidence of postoperative delirium [postoperative days 1-5]: Proportion of participants with at least one positive delirium assessment using the Nursing Delirium Screening Scale (NuDESC) or the 3-Minute Diagnostic Interview for Confusion Assessment Method-defined Delirium (3D-CAM).

Secondary outcomes

• Functional independence [3 months postoperative]: Functional independence assessed using the Functional Independence Measure (FIM). A score of 18 to 126 points can be achieved. Higher scores indicate greater independence.
• Cognitive function [3 months postoperative]: Cognitive performance assessed using the 5-minute Montreal Cognitive Assessment (5-minute MoCA). A score of 0 to 15 points can be achieved. Higher scores indicate better cognitive performance.
• Postoperative complications [30 days postoperative]: Incidence of postoperative complications, newly diagnosed conditions, and additional hospital treatment, obtained from medical records and participant interviews.

Other outcomes

• Feasibility of the delirium prevention program [from baseline (day 1) up to 30 days postoperatively.]: Feasibility of integrating the multicomponent delirium prevention program into routine clinical care, assessed using documented completion and availability of the planned care processes.
• Implementation of delirium prevention measures [from baseline (day 1) up to 30 days postoperatively]: Degree of implementation of key intervention components, including preoperative risk assessment, postoperative delirium screening, delivery of indicated preventive measures, and staff training.

Sex: All, ages: 65 Years to any

Inclusion Criteria:

* Age ≥65 years
* Scheduled for or undergoing inpatient surgery at the study site
* Able to provide written informed consent
* Sufficient language proficiency to understand the study information and complete the study assessments

Exclusion Criteria:

* Current schizophrenia
* Active alcohol dependence or harmful alcohol use
* Current drug abuse
* severe intellectual disability
* Preoperative delirium
* Inability to understand the nature, significance, and implications of study participation or to provide informed consent

• Cynthia Olotu, MD. Dr., Principal investigator, University Medical Center Hamburg