An “anesthetic complication” may be defined as any deviation from the normally expected pattern during or after the securing of regional analgesia.
Can be divided into 2 groups:
Those attributed to solutions used e.g. toxicity, idiosyncrasy, allergy, anaphylactoid reactions, infection caused by contaminated solutions, local irritation or tissue reaction
Those attributed to insertion of needle e.g. syncope, muscle trismus, pain or hyperalgesia, edema, infections, broken needles, hematoma, sloughing etc.