Sonoanatomy of the Lumbar Spine in Patients With Previous Unintentional Dural Punctures During Labor Epidurals

Abstract

Abnormal sonoanatomy of the ligamentum flavum may represent anatomical variations of this structure, which may be related to an increased incidence of unintentional dural punctures during epidural placements.

Avaliação da profundidade do espaço subaracnoideo com o uso do ultrassom

“…Lee et al have shown that ultrasonography makes it possible to detect abnormal sonoanatomy. 12 We can decrease complications such as unintentional dural punctures.…”

Pre-Procedure Neuraxial Ultrasound in Obstetric Anesthesia

“…Chin et al (20) examined the effect of using ultrasound to guide spinal anesthesia in obese orthopedic patients with poorly palpable spinous processes, and moderate to severe lumbar scoliosis or previous lumbar spine surgery, and showed successful dural puncture was achieved after the first needle insertion in 65% of cases in the ultrasound group compared to only 32% in the landmark group. The efficacy and safety of pre-procedure neuraxial ultrasound has been clearly demonstrated in multiple clinical studies (Table 2) (5,(21)(22)(23)(24).…”

Ultrasound-Guided Central Neuraxial Blocks

“…A scout scan allows one to identify the midline 34 and accurately determine the interspace for needle insertion, 3,30 which are useful in patients in whom anatomical landmarks are difficult to palpate, such as in those with obesity, 1,23 edema in the back, or abnormal anatomy (scoliosis, 23,48 postlaminectomy surgery, 45 or spinal instrumentation). 42,43,46 It also allows the operator to preview the neuraxial anatomy, 24,26,29,30,33 identify asymptomatic spinal abnormalities such as in spina bifida, 49 accurately predict the depth to the epidural space 19,20,24,26 including in the obese, 50 identify ligamentum defects, 51 and determine the optimal site and trajectory for needle insertion. 26,27 Cumulative evidence suggests that when an US examination is performed before the epidural puncture it improves the success rate of epidural access on the first attempt, 24 reduces the number of puncture attempts 23,24,26,29 or the need to puncture multiple levels, 24,26,29 and also improves patient comfort during the procedure.…”