From the Research
Performing a thoracic epidural with fluoroscopy using contralateral oblique imaging involves several precise steps to ensure accurate needle placement and patient safety, with the most recent and highest quality study 1 suggesting a contralateral oblique view at 60 degrees provides clearer visualization and more consistent needle tip location. The steps for this procedure include:
- Positioning the patient in the prone position on the fluoroscopy table with a pillow under the abdomen to reduce lumbar lordosis.
- Identifying the target thoracic level using anteroposterior (AP) fluoroscopic imaging, then rotating the C-arm 15-20 degrees toward the contralateral side to obtain the contralateral oblique view, which helps visualize the "Scotty dog" appearance of the vertebra.
- Cleaning the skin with antiseptic solution and administering local anesthetic at the entry point, which should be at the superior aspect of the inferior lamina.
- Using a 17G or 18G Tuohy needle with the bevel directed cephalad, advancing the needle under intermittent fluoroscopic guidance using the loss-of-resistance technique with either saline or air, with the contralateral oblique view providing better visualization of needle depth and trajectory.
- Injecting contrast medium to confirm proper placement by observing the characteristic epidural spread pattern, then inserting the epidural catheter 3-5 cm beyond the needle tip, removing the needle while maintaining catheter position, and securing the catheter to the skin.
- Administering a test dose to rule out intravascular or intrathecal placement before delivering the therapeutic medication, as supported by studies such as 2 which found fluoroscopic guidance increases the incidence of epidural catheter placement within the epidural space. Key considerations include:
- The use of fluoroscopic guidance to improve the safety profile of thoracic epidurals by providing better visualization of the needle path relative to critical structures like the spinal cord.
- The importance of proper patient positioning and needle placement to minimize the risk of complications.
- The value of using a contralateral oblique view at 60 degrees, as suggested by the most recent study 1, to provide clearer visualization and more consistent needle tip location.