Frontal EEG to Formal Polysomnography in the ICU

Eligibility Details: Group 1: Healthy Subjects in Sleep Lab: Inclusion Criteria - Age 18 or older - Scheduled for a standard of care polysomnography lasting at least 8 hours for any condition Exclusion Criteria - Patient/Legally Authorized Representative declines consent Group 2: ICU patient, not sedated, not ventilated Inclusion Criteria - Age 18 or older - Anticipated to stay in intensive care unit overnight (minimum 8 hours) - Glasgow Coma Scale score of 13 or great Exclusion Criteria: - Intubated with endotracheal tube - Sedated (includes sedative drugs such as propofol, Dexmedetomidine, versed infusion above 2mg/hr, ketamine infusion above 0.2 mg/kg/hr). Group 3: ICU patient, sedated and ventilated Inclusion Criteria: - Age 18 or older - Anticipated to stay in the intensive care unit overnight (minimum 8 hours) - Intubated, sedated, and ventilated Exclusion Criteria: - Presence of traumatic brain injury - Planned extubation in next 8 hours - Scheduled to leave the intensive care unit for any reason in the next 8 hours - Anticipated life expectancy of less than 24 hours - Electroencephalogram monitoring (current or scheduled in the next 8 hours) - Hemodynamic instability (defined as: (i) mean arterial pressure <60mmHg for >20 minutes with efforts to raise it or (ii) >2 liter fluid administered in 2h after operating room and anticipating on-going needs for fluid resuscitation or (iii) ICU MD determination of "atypical and profound hemodynamic instability" or (iv) PI determination after evaluation. - Refractory hypoxemia - defined as Saturation <88% on Sp02 despite efforts to increase it - Hemorrhage - defined as >500cc chest tube output in 2h and anticipated need of more than 2 units of packed red blood cells in immediate post op period. This does NOT include cell-saver.