Patients
allergic reaction, toxicity, edema, impaired neurological function, pain, infection, psychiatric
ALLERGIC REACTION, EDEMA, DYSFUNCTION, INFECTION, COAGULATION DISORDER
Inclusion criteria were patients aged 18 to 65 years; American Society of Anesthesiologists classification (ASA) I–III; ability to express pain; and patients undergoing elective surgery at or below the elbow. Exclusion criteria were patients who ﻿had neck tissue abnormality, infection, or edema; impaired neurological function; coagulation disorder; a history of an allergic reaction to local anesthetics or opioids; weighing < 40 kg (to reduce the risk of anesthetic toxicity) or > 100 kg (to reduce the difficulty of performing ISB); psychiatric dysfunction and patients who refused to sign informed consent.