Background and objectives: Unintentional subdural block, while attempting an epidural anesthetic, is a rare but known complication. The authors describe a radiologically confirmed case of an unintentional combined epidural and subdural block while attempting to perform an epidural block for transurethral resection of prostate in a middle-aged man.
Methods: Loss of resistance to air injection was used for identifying the epidural space prior to catheter placement. Following the epidural injection of 20 mL of a 1.5% lidocaine and 0.5% bupivacaine mixture, the patient developed rapid, intense, prolonged, and extensive bilateral motor block up to C2 level.
Results: The patient had aphonia and respiratory paralysis requiring endotracheal intubation and controlled ventilation for 3 hours.
Conclusions: Postoperative radiologic examination revealed the spread of the dye in both epidural and subdural spaces, causing the extensive sensory and motor block.