title: Ultrasound-Guided Superior Hypogastric Plexus Block: A Cadaveric Feasibility Study with Fluoroscopic Confirmation.
abstract: Plancarte first described a fluoroscopy-guided superior hypogastric plexus block to manage pelvic pain in 1990. Modifications have since been described using different imaging modalities. Ultrasound-guided approach has been described in a clinical outcome study. However, the accuracy of an ultrasound-guided method has never been validated by alternative imaging. We conducted an experiment aiming to develop ultrasound-guided superior hypogastric plexus block using human cadavers in the supine position. Final needle position and spread of a radiopaque contrast was verified by fluoroscopy, a standard imaging tool. The needle approach to the L5 vertebral body was performed in the short axis as has been recommended. Injection of radiopaque contrast revealed unilateral and cephalad spread to the L5/S1 disk. Additional transabdominal long-axis scanning of the lumbosacral segment was and the needle trajectory was modified to aim for the apex of the L5/S1 disk. Bilateral spread was achieved by strict midline placement of the needle tip and real-time observation of injection. The modified ultrasound-guided technique resulted in a similar spread of injectate as the traditional fluoroscopy-guided technique that in a clinical scenario would offer complete block of the superior hypogastric plexus.
authors.affiliation: Department of Anesthesia, St Michael's Hospital, University of Toronto, Toronto, Canada.
authors.forename: Michael
authors.initials: M
authors.lastname: Gofeld
authors.affiliation: Department of Anesthesia, St Michael's Hospital, University of Toronto, Toronto, Canada.
authors.forename: Chuan-Whei
authors.initials: CW
authors.lastname: Lee
mesh_terms: D000368:Aged; D002102:Cadaver; D003287:Contrast Media; D005240:Feasibility Studies; D005260:Female; D005471:Fluoroscopy; D006801:Humans; D007001:Hypogastric Plexus / Q000000981:diagnostic imaging*; D007403:Intervertebral Disc / Q000000981:diagnostic imaging; D008160:Lumbosacral Plexus / Q000000981:diagnostic imaging; D008297:Male; D009339:Needles; D009407:Nerve Block / Q000379:methods*; D014463:Ultrasonography; D018084:Ultrasonography, Interventional / Q000379:methods*
chemical_list: D003287:Contrast Media
keywords: pelvic pain; superior hypogastric plexus; sympathetic chain; ultrasound-guided