Accidental epidural catheterization during continuous interscalene block via the posterior approach

Abstract

In recent years, interscalene catheterization via the posterior approach and continuous local anesthetic infusion has been suggested for pain relief related to brachial plexus tumor infiltration. Improper catheterization could lead to complications such as epidural or spinal anesthesia or phrenic nerve paralysis. A 54 year old man was referred to our pain clinic with severe right upper extremity and shoulder pain, dysesthesia and allodynia involving the right C7-T1 dermatomes, and 3/5 strength loss of the right forearm due to inoperable apical lung tumor with brachial plexus infiltration. For pain relief, a continuous interscalene block via the posterior approach was performed in the sitting position. Four millilitres 1% lidocaine without epinephrine were administered through the catheter. Approximately 5 minutes after the injection, the patient developed respiratory distress and dizziness. Fifteen minutes after the injection, side effects regressed and the vital signs stabilized. To confirm catheter position, 5 ml of contrast medium were injected and a C-arm fluoroscopic imaging showed contrast medium in the epidural space with catheter opacification. We suggest that the patient should be awake and conscious during catheter placement; radiographic confirmation of catheter position should be obtained before the first injection, and after each local anesthetic injection the patient should be monitored. © 2005 VSP.