Epidural analgesia is commonly used to provide several types of pain relief. Although this technique has been widely used with many advantages, currently the complications appear to be increasing. Especially, inadvertent intravascular cannulation and intravascular local anesthetic administration can lead to fatal consequences.

Data was collected on 296 patients undergoing elective thoracic or abdominal surgery. Two detection methods were utilized to confirm the epidural intravascular cannulation; flashback and aspiration of indwelling catheter, and injection of a contrast agent through the catheter under fluoroscopy were used to guide the placement of the catheter and to examine the intravascular cannulation.

Epidural intravascular cannulation was reported in 4 out of 296 cases (1.4%), and 1 patient underwent subdural cannulation. Among the 4 cases of epidural intravascular cannulation, two were confirmed by the flashback and aspiration methods, while the remaining cases were only detected by real time fluoroscopy.

In this study, inadvertent epidural intravascular cannulation occurred by as much as 1.4% of thoracic epidural catheterization. Utilizing real time fluoroscopy in addition to flashback and aspiration can enhance the sensitivity of detection.