• Younger than 2 years (chronological age)
• Scheduled for anaesthesia that is expected to last at least 2 hours (and/or total operating room time is scheduled to be at least 2.5 hours)
• Has a legally acceptable representative capable of understanding the informed consent document and providing consent on the participant's behalf.
• Known neurologic, chromosomal or congenital anomaly which is likely to be associated with poor neurobehavioural outcome
• Existing diagnosis of behavioural or neurodevelopmental disability
• Prematurity (defined as < 36 weeks gestational age at birth)
• Birth weight less than 2 kg.
• Congenital cardiac disease requiring surgery
• Intracranial neurosurgery and intracranial craniofacial surgery (isolated cleft lip is not an exclusion)
• Previous cumulative exposure to general anaesthesia exceeding 2 hours
• Planned future cumulative exposure to anaesthesia exceeding 2 hours before the age of 3 years.
• Any specific contra-indication to any aspect of the protocol
• Previous adverse reaction to any anaesthetic
• Circumstances likely to make long term follow-up impossible
• Living in a household where the primary language spoken at home is not a language in which we can administer the Wechsler Preschool and Primary School Intelligence Scale
• Planned postoperative sedation with any agent except opioids (e.g. benzodiazepines, dexmedetomidine, ketamine, barbiturates, propofol, clonidine, chloral hydrate, and other non-opioid sedatives). For example if such sedation is planned for post-operative ventilation

1. Shoulder pain of >3 months 2. Age>=21 3. Worst pain in the last week>=4 (0-10 scale) 4. Ability to check skin and perform dressing changes, independently or with assistance 5. Stable dose of pain medication (Not taking more than than 1 opioid or 1 non-opioid analgesic) 1. Current shoulder joint or overlying skin infection, or current bacterial infection requiring antibiotics 2. Other chronic pain syndrome (Pain in another area of the body 15 or more days in the last 30 (more than half of the time) or taking daily analgesics for another pain syndrome) 3. Prior shoulder surgery to ipsilateral shoulder joint (glenohumeral, rotator cuff, acromioclavicular (AC) Joint, etc.) 4. Corticosteroid injection in the ipsilateral shoulder or any other pain relieving treatment in last 12 weeks 5. Uncontrolled bleeding disorder 6. Medical instability based on physician opinion after review of medical information 7. Pregnancy 8. Neurological condition affecting ipsilateral upper limb (such as central neurologic injury/illness, radiculopathy, diabetic amyotrophy, Complex Regional Pain Syndrome, etc.) 9. Current Worker's compensation claim for the ipsilateral shoulder 10. Shoulder instability, severe glenohumeral osteoarthritis(OA) based on patient symptoms and physical examination 11. Ipsilateral shoulder injury due to severe trauma (Fall from greater than standing height; Motor vehicle crashes; Struck by vehicle or other fast-moving projectile (e.g., bullet, baseball, etc.); Assault (i.e., injuries intentionally inflicted by another person)) 12. Current osseus fracture in ipsilateral arm 13. Ipsilateral upper limb amputation other than a single digit (digits 2-5, partial or full) 14. Surgical indication for shoulder treatment based on physician opinion 15. Compromised immune system (immunodeficiency or immunosuppression) 16. Current use of a Deep Brain Stimulation (DBS) system, implanted active cardiac implant (e.g. pacemaker or defibrillator), any other implantable neuro-stimulator whose stimulus current pathway may overlap with that of the SPRINT System 17. Patients who have a tape or adhesive allergy 18. Contraindication to Magnetic resonance imaging (metal in body, claustrophobia, body habitus, etc)
•exclude from Magnetic resonance imaging (MRI) only

1. Adult patients (age ≥18 years old) 2. Having endoscopic procedure at CUH with anesthesia 3. ASA 3 or above 4. Ejection Fraction test result available 1. Known allergies or adverse reactions to study drugs or study drug components or preservatives 2. Patient refusal 3. Clinician refusal 4. Documented cognitive impairments precluding subject ability to consent for themselves unless a surrogate documented legally acceptable decision maker consents for patient participation 5. Prisoner or incarcerated or patients held by law enforcement officials in custody 6. Pregnancy or patient refusal for pregnancy testing or screening (standard UTSW policy and protocol requires pregnancy testing for appropriate patients prior to anesthesia)

• Female ASA physical status 1-3 scheduled for open abdominal hysterectomy
• Age 18-80 years old
• Able to participate personally or by legal representative in informed consent in English or Spanish
• History of relevant drug allergy
• Age less than 18 or greater than 80 years
• Chronic opioid use or drug abuse
• Active use of anticoagulant medication
• Significant psychiatric disturbance
• Inability to understand the study protocol
• Refusal to provide written consent

• Willingness and ability to cooperate during conscious operative procedure for up to 40 minutes
• Clinical diagnosis of Parkinson's disease or essential tremor
• Preoperative MRI without evidence of cortical or subdural adhesions or vascular abnormalities
• Patients with recent use (within one week) of anticoagulant or antiplatelet agent use
• Neurocognitive testing indicating amnestic cognitive deficits
• History of intolerance of propofol or medical indications to use an anesthetic other than propofol