Ultrasound-Guided Superior Hypogastric Plexus Block

Paul E. Bigeleisen

Background and indications: Traditionally, hypogastric plexus block was performed by anesthesiologists from a posterior approach using fluoroscopy or computed tomography (CT) guidance. This procedure was technically difficult because it required the practitioner to advance the needle between the wing of the posterior iliac crest and vertebral body into a position anterior to the vertebra at the L5-S1 junction. Radiologists often used an anterior approach with fluoroscopy or CT guidance in which the needle was advanced through the abdominal wall until it was immediately anterior to the anterior longitudinal ligament of the vertebrae. This same approach is easy to perform with ultrasound and has the advantage over fluoroscopy that the aorta and iliac arteries are readily imaged. Because this approach requires the needle to traverse the small bowel and peritoneum, the patient should be treated with broad-spectrum antibiotic prophylaxis prior to the procedure. The author’s preference is 2 g of cefoxitin.

Block of the superior hypogastric plexus is used as a diagnostic procedure or therapeutic treatment of pain syndromes related to the testes, ovaries, uterus, cervix, vagina, bladder, sigmoid colon, and rectum. Ultrasound guidance can be used for the anterior approach to the superior hypogastric plexus. When neurolytic blocks are intended, the practitioner must be aware that bowel and bladder incontinence or dysfunction may ensue. For this reason, neurolytic blocks are usually reserved for patients with terminal cancer of the above-named organs.

Anatomy: The superior hypogastric plexus contains contributions from the intermesentEric plexus, which descends over the aortic bifurcation. It also receives branches from the two lower lumbar splanchnic nerves. The plexus carries visceral efferents to and somatic afferents from the testes, ovaries, uterus, cervix, vagina, bladder, sigmoid colon, and rectum. The plexus lies anterior to the fourth and fifth lumbar and the sacrum (Fig. 47.1). Below the junction of the lumbar vertebrae and sacrum, the plexus bifurcates into the right and left hypogastric nerves.