Evaluating Hemidiaphragmatic Paralysis With Prolonged Neural Blockade From an Interscalene Brachial Plexus Block

Inclusion Criteria: * English speaking 18-80 year old ASA 1-3 patients * Primary shoulder surgery * Must live within a 25 mile radius Exclusion Criteria: * ASA 4 or 5 * Revision shoulder surgery * Diagnosis of chronic pain * Daily chronic opioid use (over 3 months of continuous opioid use) * Inability to communicate pain scores or need for analgesia * Infection at the site of block placement * Age under 18 years old or greater than 80 years old * Pregnant women (as determined by point-of-care serum bHCG) * Intolerance/allergy to local anesthetics * Weight \<50 kg * BMI \> 40 * severe pulmonary disease including chronic obstructive pulmonary disease and restrictive lung disease * Suspected, or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past 2 years. * Uncontrolled anxiety, schizophrenia, or other psychiatric disorder that, in the opinion of the investigator, may interfere with study assessments or compliance. * Current or historical evidence of any clinically significant disease or condition that, in the opinion of the investigator, may increase the risk of surgery or complicate the subject's postoperative course.