2025 FSA Podium and Poster Abstracts

Background: Lumbar epidural placement is a foundational procedure within obstetric anesthesia. It is practiced widely using variations of the traditional blind technique; however, several rudimentary, three-dimensional, and artificial-intelligence assisted ultrasound exist for populations with complicated anatomy and low-predicted success of the procedure (1). A "difficult back" represents an interplay of anatomical, physiological, and pathological factors that impede precise epidural space cannulation. This includes aberrant spinal architecture including scoliosis and subtle variations in intervertebral disc height, as well as degenerative changes, osteophyte formation, and ligamentous calcification. Increased tissue impedance, due to obesity or prior surgical fibrosis, also obscures landmarks and creates resistance to needle advancement. Additionally, physiological and pathological constraints from conditions like ankylosing spondylitis or underlying coagulopathies further complicate the procedure.

Methods: Ultrasound-guided methods are often forgone by practitioners in favor of the traditional blind technique out of technical preference and subjective prior experience despite the potential for improved provider success and patient satisfaction. For example, patients with a history of spinal fusion have not only a lower chance of successful blind epidural placement, but also a higher risk of prolonged procedure time and multiple required attempts (2). Concurrently, use of rudimentary ultrasound has shown improved first attempt success, number of required attempts, and overall procedural and needling times (3).

Case: This is the case of a 27-year-old female, G1P0 at 40 weeks and 0 days gestation, with a history of L2-L4 fractures and subsequent spinal fusion following a motor vehicle collision presenting to a small community hospital in labor for epidural analgesia. She was displaced from her home hospital by a hurricane but brought imaging of her spinal fusion as well as a note from her obstetrician stating that she was "not a candidate for epidural anesthesia" due to her previous spinal surgery. She was deemed a high risk for epidural placement failure, multiple attempts, and prolonged procedural time, but offered an attempt at epidural placement using ultrasound assistance. She was also offered the option of remifentanil infusion for labor and made aware that she would require general anesthesia if a cesarean section was necessary due to the similar difficulty of placing a spinal anesthetic. She elected to attempt the epidural. First pass epidural placement was successfully achieved using the hand-held ultrasound with three-dimensional rendering and needle-approach guidance. Patient delivered with no epidural complications during the course of her labor.

Discussion: Successful placement of this epidural was accredited to the aid of the visual guidance by the physician who performed the procedure. The near-ubiquitous application of ultrasound imaging in vascular procedures, regional anesthesia, and clinical diagnostics where palpation and auscultation used to prevail is a trend that should not be resisted by obstetric anesthesia. While the data on the ultrasound used in this case is not perfect, there is a growing body of evidence showing advantages of visualization over traditional blind techniques (4,5), particularly in patients that would be categorized pre-procedurally as “difficult”.

1. DOI: 10.4103/joacp.JOACP_340_18
2. DOI: 10.4103/2249-4472.191594
3. DOI: 10.1002/hsr2.70039
4. DOI: 10.1007/s00540-021-02922-y
5. DOI: 10.1177/17504589231215927