Neuraxial anaesthesia in the parturient with pre-existing structural spinal pathology

Question 1

Spondylolisthesis in pregnancy

Answer 1

Displacement of a vertebral body on the one below caused by intersegmental instability of the vertebrae.
Can cause stretching of the dura and contraction of the epidural space therefore inserting an epidural needle at the level of the spondylolisthesis increases the risk of dural puncture,

Question 2

Scoliosis in pregnancy

Answer 2

> 10 degree lateral curvature of the spine in the sitting position (most common cause idiopathic, can be congenital or due to neuromuscular disorders).

Uncorrected: USS of midline is prudent, may produce unilateral spread
Corrected: If anterior then ok for neuraxial, if posterior then unlikely to be successful with technique or spread. Require careful pre-op counselling and details from the spinal surgery

Question 3

Lumbar spinal surgery in pregnancy (discectomy, laminectomy, lumbar fusion)

Answer 3

Need spinal surgical details re potential for epidural fibrosis, loss of ligamentum flavum etc.

Question 4

Spinal Dysraphism in pregnancy

Answer 4

Refers to a range of conditions encompassing abnormalities of the vertebral arches, spinal cord or meningeal structures. Can be divided into open (meninges open to air) or closed (meninges protected by skin). MRI and counselling is a must. Neuraxial techniques have been performed but should be done so with caution and counselling especially if the spinal cord is tethered. Thorough neuro exam is recommended.