The study was closed prematurely due to low enrollment and anticipation of future barriers in enrollment

The patients included will be those who have already agreed to have a brachial plexus nerve block for surgery. A flip of the coin will decide who gets and additive called buprenorphine in their block or not. They will both contain the same amount and type of numbing medicine. The goal will be to see if the additive extends the life of the pain control portion of the ultrasound guided supraclavicular nerve block.

Inclusion Criteria:

1. American Society of Anesthesiologists (ASA) physical status 1-3
2. Age 18-79, inclusive
3. BMI <36 kg/m^2
4. Patient consenting to single injection brachial plexus nerve block as primary anesthetic for a procedure

Exclusion Criteria:

1. Patients with coagulation disorders
2. Clinically significant pulmonary disease
3. Clinically significant cardiac disease
4. Neurologic deficit in surgical extremity
5. Allergy to bupivacaine or buprenorphine
6. Intolerance of narcotics
7. Local infection over intended area of needle insertion
8. Hepatic failure or renal failure
9. Significant psychiatric disease, including drug abuse
10. Seizure disorder
11. Possible pregnancy or lactation by patient report
12. Use of narcotic medication greater than 2 times a week for greater than 1 week.
13. Patients for whom the surgeon requests a shorter-acting block