Epidural Anesthesia : Unintended Intrathecal Injection

Case Synopsis

A frail, 55-kg, 79-year-old woman is admitted for elective hip replacement as the first surgery of the day in a specialty orthopedic surgery center. An epidural catheter is placed for surgical anesthesia and postoperative analgesia. With the patient sitting on the operating room table, catheter placement is uneventful. Fifteen milliliters of local anesthetic (2% lidocaine with 5 μg/mL of epinephrine) is administered via the catheter in three 5-mL doses over 3 minutes. Pain in the arthritic hip is immediately relieved, and the patient’s lower extremities become insensate. Five minutes later, she complains of weakness and experiences difficulty breathing. She then becomes apneic and unconscious, with subsequent oxygen desaturation and hypotension. She is ventilated with a mask and then intubated. Blood pressure is maintained with ephedrine and intravenous fluid.