for people ages 18-100 (full criteria)
study started
estimated completion
Robert L. Owens



Sleep deprivation is known to affect brain function but is often ignored in the sickest patients including those in the intensive care unit after major surgery. In these patients, the levels of melatonin can also be altered. Melatonin is a hormone secreted in the brain that maintains the body's sleep-wake, or circadian, cycle. The investigators want to test whether improving sleep quality affects the risk of developing confusion (delirium) in patients having clot removed from their lung (open heart surgery). In order to improve sleep quality, the investigators will conduct a study of Ramelteon, a medication that mimics the activity of melatonin and measure its effects on levels of melatonin and monitor sleep.


Delirium Sleep Deprivation Ramelteon


You can join if…

Open to people ages 18-100

  • Patients with Chronic Thromboembolic Pulmonary Hypertension (CTEPH) who are admitted to UCSD for a planned PTE surgery.
  • Age > 18 years

You CAN'T join if...

  • Pregnancy
  • Cirrhosis of any etiology
  • Current use of any atypical antipsychotic including Fluvoxamine (contra-indicated with Ramelteon)
  • Any contraindication to EEG/Sleep recording
  • Non-English speaking (who are unable to complete delirium questionnaires)

Lead Scientist

  • Robert L. Owens
    Associate Professor In Residence, Medicine. Authored (or co-authored) 106 research publications


in progress, not accepting new patients
Start Date
Completion Date
University of California, San Diego
Study Type
Last Updated