Here is the design of a clinical trial:

Official Title: Dexmedetomidine After Cardiac Surgery for Prevention of Delirium: The Exactum Study a Randomised Double Blind Controlled Trial

Included conditions:
- ICU Delirium

Study Armgroups:
- {'label': 'Dexmédétomidine', 'type': 'ACTIVE_COMPARATOR', 'description': 'Intravenous infusion with electric syringe of Dexmedetomidine 0,4ug/ml. Rate 0,1ug/kg/h to 1,4ug/kg/h. Nightly infusion from 20:00 to 08:00. The drug is titrated to achieve RASS between -1 and 1. Modification of infusion rate by 0,1ug/kg/h is recommended with stabilization phase of 1 hour before another rate adjustment.', 'interventionNames': ['Drug: Dexmedetomidine']}
- {'label': 'Sodium Chloride 0,9%', 'type': 'PLACEBO_COMPARATOR', 'description': 'Intravenous infusion with electric syringe of normal saline. Rate modifications follow the same rules as in experimental group.', 'interventionNames': ['Drug: Sodium chloride 0.9%']}

Interventions:
- {'type': 'DRUG', 'name': 'Dexmedetomidine', 'description': 'Intravenous infusion with electric syringe of Dexmedetomidine 0,4ug/ml. Rate 0,1ug/kg/h to 1,4ug/kg/h. Nightly infusion from 20:00 to 08:00. The drug is titrated to achieve RASS between -1 and 1. Modification of infusion rate by 0,1ug/kg/h is recommended with stabilization phase of 1 hour before another rate adjustment.', 'armGroupLabels': ['Dexmédétomidine']}
- {'type': 'DRUG', 'name': 'Sodium chloride 0.9%', 'description': 'Intravenous infusion with electric syringe of normal saline. Rate modifications follow the same rules as in experimental group.', 'armGroupLabels': ['Sodium Chloride 0,9%']}

Primary Outcomes:
- {'measure': 'Delirium', 'description': 'Occurrence of delirium diagnosed by the Confusion Assessment Method (CAM ICU) at any time in the first seven days after surgery', 'timeFrame': '7 days'}

Please estimate the sample size based on the assumption: 
One-sided alpha=0.05, 90% power, and a 5% loss-to-follow-up rate.
Sample size calculation
        In three randomised controlled trials on postoperative delirium in elderly patients undergoing cardiac surgery, delirium incidence varied from 13.7% to 34.0%.18â20 Based on this literature, we hypothesised a delirium incidence of 25% in the population studied. In two of the three studies, the magnitude of the treatment effect was a 50% decrease of postoperative delirium and subsyndromal delirium.18 19 Therefore, a 50% decrease in incidence of delirium was chosen to remain in line with the previous publications. Using a one-sided alpha=0.05% and 90% power, a sample size of 332 is needed. Considering a loss-to-follow-up rate of 5%, we plan to enrol 348 patients.
        A one-sided alpha was chosen because no publication reported any worsening of the patientâs outcome compared with placebo. A two-sided alpha estimate is more robust but requires a bigger sample size.