Delirium Treatment With Transcranial Electrical Stimulation
The goal of this clinical trial is to investigate the effectiveness of standardized and personalized transcranial alternating current stimulation (tACS) in patients with postoperative delirium. To investigate this, will perform a double-blind, randomized, sham-controlled, multicenter trial.

To test the safety and feasibility of tACS in delirious patients, the first 30 patients will be randomized to receive either active or sham tACS treatment in a 1:1 ratio through a pilot study. For the main phase of the study, patients will be randomized, resulting in an overall 1:1:1 allocation to standardized tACS, personalized tACS or sham treatment.

Electroencephalogram (EEG) will be measured directly before and directly after the first stimulation session to assess whether tACS can reduce relative delta power. tACS or sham treatment will be given once daily for a maximum of 14 days, or until resolution of delirium or discharge (whichever comes first). During the treatment phase, presence and severity of delirium will be assessed daily. After the treatment phase, an additional EEG will be measured. Cognitive status will be assessed three months postoperative.
- EligibilityCriteria: Inclusion Criteria:  Age over 50 years. Diagnosis of postoperative delirium that started within the first three days after surgery. Richmond Agitation and Sedation Scale (RASS) score of -2 to +2. Delirium duration of at least two days prior to study inclusion, based delirium assessments and/or descriptions in the medical and/or nursing files. Known causes underlying delirium are being treated adequately, as assessed by the treating physician.  Exclusion Criteria:  Inability to conduct delirium assessment (e.g. coma, deaf, blind) or inability to speak Dutch or English. A moribund state. Alcohol/substance abuse withdrawal as precipitating factor for delirium. Diagnosis of dementia, based on medical record review and/or a score of ≥4.5 on the short form of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE)  One or more contra-indications for tACS:  History of serious head trauma or brain surgery; Large or ferromagnetic metal parts in the head (except for a dental wire); Implanted cardiac pacemaker or neurostimulator; Skin diseases or inflammations ; Epilepsy. - HealthyVolunteers: No - Gender: All - MinimumAge: 50 Years - StdAgeList: Adult, Older Adult