Tuohy needle

Literally, an epidural needle is simply a needle that is placed into the epidural space. To provide continuous epidural analgesia or anesthesia, a small hollow catheter may be threaded through the epidural needle into the epidural space, and left there while the needle is removed. There are multiple types of epidural needles as well as catheters, but in modern practice in developed nations, disposable materials are used to ensure sterility.

Epidural needles are designed with a curved tip to help prevent puncture of the dural membrane. But following accidental dural puncture, headache occurs in up to 85% of patients causing significant perioperative morbidity.[1] However, in case of inadvertent dural perforation, the incidence of headache can be lowered by identifying the epidural space with the needle bevel oriented parallel to the longitudinal dural fibers which limits the size of the subsequent dural tear.[2]

Close-up of needle and catheter tip, showing the curved end at the needle's tip. The needle features an anti-coring curve at its tip designed to cause a catheter passing through the needle's lumen to exit laterally at a 45 degree angle.

Though Ralph L. Huber (1915–2006), a Seattle dentist, was the inventor of this needle in 1940, it is known in the name of Edward Boyce Tuohy (1908–1959), a 20th-century U.S anesthesiologist who first popularized it in 1945.[4]

• "The Evolution of Spinal and Epidural Needles : From the Origins to the Current". Cothon.Net.
• Frölich, MA; Caton, D (July 2001). "Pioneers in epidural needle design". Anesthesia and Analgesia. 93 (1): 215–20. doi:10.1097/00000539-200107000-00043. PMID 11429369.