Role of Natural Light in the Prevention of Delirium After Cardiac Surgery: a Prospective Observational Study With Historical Control (iWOnDer)

Ruolo Della Luce Naturale Nella Prevenzione Del Delirium Dopo Cardiochirurgia: Studio Osservazionale Prospettico Con Controllo Storico

Postoperative delirium is a common complication that usually occurs acutely within the first 24 hours after surgery and resolves within 72 hours; it is common in all medical areas and particularly affects patients over the age of 65 and those with pre-existing cognitive impairments. It is characterized by difficulty organizing and coordinating thoughts and by slowing down motor functions that are observed for a short period after surgery.

The study will be an observational prospective study with historical control (pre/post-study) whose primary objective is to identify the incidence of postoperative delirium in patients undergoing cardiac surgery. The population will be adult patients undergoing cardiac surgery at our University Hospital over a period of 12 months. The intervention will be exposure to totally artificial light (for patients hospitalized after the relocation of the department to its original location). The comparator will be exposure to natural light (for patients who will be hospitalized during our temporary transfer to an environment with natural lighting). The outcome will be the incidence of delirium, measured with the Confusion Assessment Method-Intensive Care Unit (CAM-ICU) scale; episodes of agitation requiring sedative drugs; time elapsed before onset of delirium. The study will last 12 months.

Study Overview

• Status: Completed
• Conditions: Postoperative Delirium; Cardiac Surgery; Intensive Care Unit Delirium
• Intervention / Treatment: Other: Exposure to totally artificial lighting

• Study Type: Observational
• Enrollment (Actual): 448

Contacts and Locations

Study Locations

• Italy
  • PR
    • Parma, PR, Italy, 43126
      • Ospedale Maggiore di Parma

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

All adult patients undergoing cardiac surgery with planned postoperative ICU admission. All tipes of cardiac surgery, irrespective of surgical access or technique, but excluding surgery performed under total circulatory arrest (totale suspension of brain perfusion). Patients will be excluded if they are unable to perform CAM-ICU assessment, if they were diagnosed with major depression or moderate/severe dementia and if they were already in ICU before surgery. Emergent surgery will also be an exclusion criteria.

Description

Inclusion Criteria:

• planned cardiac surgery
• planned ICU admission after surgery

Exclusion Criteria:

• cardiac surgery with total suspension of cerebral perfusion
• patient with diagnosed dementia or major depressive disorder
• patient unable to perform CAM-ICU evaluation
• emergent surgery
• patient in ICU before surgery

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Natural Light; Group of patients enrolled in the first ICU, with natural lighting
Artificial Light; Group of patients enrolled in the second ICU, with totally artificial lighting	Other: Exposure to totally artificial lighting; The second group of patients will be admitted to an ICU without windows and with a totally artificial lighting

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative delirium	Occurrence of delirium, diagnosed with at least one positive CAM-ICU evaluation	first five postoperative days or ICU discharge (wichever comes first)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative episodes of agitation	number of episodes of postoperative agitation (RASS>+1) requiring farmacological treatment	first five postoperative days or ICU discharge (wichever comes first)

Collaborators and Investigators

• Sponsor: Azienda Ospedaliero-Universitaria di Parma

Study record dates

Study Major Dates

• Study Start (Actual): June 14, 2023
• Primary Completion (Actual): June 22, 2024
• Study Completion (Actual): June 22, 2024

Study Registration Dates

• First Submitted: June 30, 2023
• First Submitted That Met QC Criteria: June 30, 2023
• First Posted (Actual): July 10, 2023

Study Record Updates

• Last Update Posted (Estimated): October 2, 2025
• Last Update Submitted That Met QC Criteria: October 1, 2025
• Last Verified: October 1, 2025

More Information

Terms related to this study

• Keywords: cardiac surgery; postoperative delirium; natural light
• Additional Relevant MeSH Terms: Neurologic Manifestations; Nervous System Diseases; Mental Disorders; Postoperative Complications; Pathologic Processes; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Delirium; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Emergence Delirium
• Other Study ID Numbers: SIRER 6097

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No