Delayed bilateral spinal anaesthesia following interscalene brachial plexus block

Abstract

Purpose: To present a case of delayed neuraxial blockade after interscalene brachial plexus block. Clinical features: A 65-yr-old lady presenting for radial head excision underwent a right interscalene block using bupivacaine and lidocaine. She experienced excellent anaesthesia and had stable vital signs for the duration of surgery. However, after 65 min, she developed signs of bilateral neuraxial block, progressing over the following hour to involve the cervical to lumbar dermatomes, with sparing of the phrenic nerves. The patient remained alert and communicative throughout with haemodynamic stability. Two days following the block, the patient experienced severe frontal and occipital pain, typical of a post dural puncture headache, which responded to fluids and recumbency. Conclusion: This example of delayed central neural blockade complicating interscalene block is presented in contrast to other reports, which have usually occurred promptly after injection, accompanied by complete sensory and motor block requiring cardio-respiratory support. The presumed mechanism of the delayed onset of bilateral neuraxial spread was a dural cuff puncture with slow CSF spread from a plexus sheath 'depot' of local anaesthetic.