Here is the design of a clinical trial:

Official Title: Shaping Anesthetic Techniques to Reduce Post-Operative Delirium

Included conditions:
- Delirium
- Lumbar Radiculopathy
- Lumbar Osteoarthritis
- Lumbar Spine Disc Degeneration

Study Armgroups:
- {'label': 'General anesthesia', 'type': 'ACTIVE_COMPARATOR', 'description': 'In this group patients will receive general anesthesia. Anesthetic induction will occur with propofol (generally 1-2 mg/kg), maintenance with a volatile anesthetic, muscle paralysis with a muscle relaxant, and pain control with fentanyl (generally 2-5 mcg/kg titrated). Patients on baseline opioids may receive additional opioids (such as dilaudid) based on clinical criteria. The anesthetic provider will be blinded to BIS values. Discretionary use of intrathecal morphine may be used.', 'interventionNames': ['Procedure: Induction with propofol', 'Procedure: Maintenance anesthetic using a volatile anesthetic', 'Procedure: Muscle relaxant during maintenance anesthesia', 'Procedure: Pain control with fentanyl', 'Procedure: Bispectral Index (BIS) monitoring for depth of anesthesia', 'Procedure: Cerebrospinal fluid collection', 'Procedure: Administration of intrathecal morphine']}
- {'label': 'Spinal anesthesia with light sedation', 'type': 'EXPERIMENTAL', 'description': 'In this group patients will receive light sedation with propofol and a spinal anesthetic. Spinal anesthesia will be obtained by injecting approximately 10-15 mg of bupivacaine into the subarachnoid space. Up to 2 mg of midazolam may be given during spinal needle insertion. Although spinal anesthesia is sufficient for surgery, sedation is routinely administered using a propofol infusion, titrated to a BIS\\>60-70. Discretionary use of intrathecal morphine may be used.', 'interventionNames': ['Procedure: Light sedation with propofol', 'Procedure: Bispectral Index (BIS) monitoring for depth of anesthesia', 'Procedure: Spinal Anesthesia', 'Procedure: Midazolam administered during spinal anesthesia', 'Procedure: Cerebrospinal fluid collection', 'Procedure: Administration of intrathecal morphine']}

Interventions:
- {'type': 'PROCEDURE', 'name': 'Light sedation with propofol', 'description': 'Patients having lumbar spinal surgery and receiving spinal anesthesia will receive propofol for light sedation.', 'armGroupLabels': ['Spinal anesthesia with light sedation']}
- {'type': 'PROCEDURE', 'name': 'Induction with propofol', 'description': 'Patients having lumbar spinal surgery and receiving general anesthesia will receive propofol and their induction agent.', 'armGroupLabels': ['General anesthesia']}
- {'type': 'PROCEDURE', 'name': 'Maintenance anesthetic using a volatile anesthetic', 'description': 'Patients having lumbar spinal surgery and receiving general anesthesia will receive a volatile anesthetic for their maintenance anesthesia.', 'armGroupLabels': ['General anesthesia']}
- {'type': 'PROCEDURE', 'name': 'Muscle relaxant during maintenance anesthesia', 'description': 'Patients having lumbar spinal surgery and receiving general anesthesia with receive a muscle relaxant for muscle paralysis.', 'armGroupLabels': ['General anesthesia']}
- {'type': 'PROCEDURE', 'name': 'Pain control with fentanyl', 'description': 'Patients having lumbar spinal surgery and receiving general anesthesia will receive fentanyl for their pain during surgery.', 'armGroupLabels': ['General anesthesia']}
- {'type': 'PROCEDURE', 'name': 'Bispectral Index (BIS) monitoring for depth of anesthesia', 'description': "All patients will be monitored with Bispectral Index (BIS) to monitor the patient's depth of anesthesia.", 'armGroupLabels': ['General anesthesia', 'Spinal anesthesia with light sedation']}
- {'type': 'PROCEDURE', 'name': 'Spinal Anesthesia', 'description': 'Patients receiving spinal anesthesia will receive bupivacaine into the subarachnoid space.', 'armGroupLabels': ['Spinal anesthesia with light sedation']}
- {'type': 'PROCEDURE', 'name': 'Midazolam administered during spinal anesthesia', 'description': 'Midazolam may be administered during spinal needle insertion for patients receiving spinal anesthesia.', 'armGroupLabels': ['Spinal anesthesia with light sedation']}
- {'type': 'PROCEDURE', 'name': 'Cerebrospinal fluid collection', 'description': '8 ml of cerebrospinal fluid may be collected prior to the administration of intrathecal administration of morphine for pain control.', 'armGroupLabels': ['General anesthesia', 'Spinal anesthesia with light sedation']}
- {'type': 'PROCEDURE', 'name': 'Administration of intrathecal morphine', 'description': 'Patient may receive intrathecal morphine for post-operative pain control.', 'armGroupLabels': ['General anesthesia', 'Spinal anesthesia with light sedation']}

Primary Outcomes:
- {'measure': 'Incidence of delirium', 'description': 'The patient will be assessed for delirium using the Confusion Assessment Method on each of the first 3 post-operative days.', 'timeFrame': 'First 3 postoperative days'}

Please estimate the sample size based on the assumption: 
Significance level of 0.05, power of 0.8, and an estimated 6% withdrawal rate.
Sample size
        Assuming a delirium incidence of 35% in the control and a 50% reduction in the intervention group [2, 20], 206 patients would be needed to show a difference in incidence of delirium at a 0.05 significance level with a power of 0.8. With an estimated 6% withdrawal, the target enrollment is 218 patients. The expected sample size of 206 patients will also be sufficient for the secondary outcome of MMSE change at 3-months after surgery: the minimum detectable change in MMSE with 206 patients is Â±0.235 at a 0.05 significance level with a power of 0.8.