Delayed quadriparesis after an interscalene brachial plexus block and general anesthesia: a differential diagnosis.

Interscalene brachial plexus block has been widely used for upper limb surgery. Different neurological complications related to this technique have been published. We report a case of quadriparesis of delayed onset, without loss of consciousness or cardiopulmonary compromise after an interscalene block and general anesthesia in a seated position. Postoperative quadriparesis, although infrequent, can occur through different causes and mechanisms. Central progression of an interscalene block can produce acute or subacute quadriparesis depending on technical factors of the placement of the local anesthetic and its subsequent spread. The symptomatology and the imaging enabled us to refine the differential diagnoses and to exclude other causes of neurologic compromise.