Functional Anatomy of the SpineWith Anesthesiology Correlates

John Angelo Luigi S. PerezSt. Luke's Medical Center - QCMarch 27, 2015

The spine is composed of 33 vertebrae

Stacked vertebrae form the spinal column

Parts of the vertebral body are used as landmarks

The spinal cord is supplied by 2 main arteries

There are multiple layers that wrap the spinal cord

There are multiple layers that wrap the spinal cord

Correlations in AnesthesiaSpinal and Epidural Anesthesia

Surface landmarks are used to determine the point of puncture

Puncturing below L1 prevents cord trauma

What is injected?

Where is it injected?

What is affected?

Dose?

Spinal LocalAnesthetic

CSF Cord Small

Epidural Epidural space NerveRoots

Large

There are key differences between spinal and epidural anesthesia

Different structures are affected in spinal and epidural anesthesia

Different structures are affected in spinal and epidural anesthesia

Different structures are affected in spinal and epidural anesthesia

Epidural Anesthesia

Spinal Anesthesia

Anesthetics have different baricities

CSF

Hypobaric

Hyperbaric

Body position and baricity interact

Hypobaric

Hyperbaric

Anesthesia is achieved in a gradient

M, Sen, Sym

Sen, Sym

Sym

Questions?

● Multiple components of support

● Anesthesia can be done differently

● Anatomy means safe anesthesia