Inclusion Criteria:  aged 18 to 60 years American Society of Anesthesiologists class I and II Scheduled for elective surgery of the upper extremities  Exclusion Criteria:  allergy to local anesthetic or hyaluronidase Severe renal or hepatic disease Pulmonary, cardiac disease Neurologic, psychiatric disease Neuromuscular disease Pregnant or lactating women Morbid obesity Coagulation disorders as well