What is the Difference Between Spinal and Epidural Anesthesia?

Spinal and epidural anesthesia are both regional anesthetics that numb parts of the body to block pain. They are delivered through injections in or around the spine, but there are differences in their administration and effects:

1. Injection site: Spinal anesthesia involves injecting numbing medicine directly into the fluid sac surrounding the spinal cord, while epidural anesthesia involves injecting the medicine into the space outside the sac (epidural space).
2. Onset and duration: Spinal anesthesia provides immediate pain relief, but its effects usually last for about 90 minutes. Epidural anesthesia takes longer to establish the desired effect, but a catheter can be placed in the epidural space, allowing for repeated doses of medicine to maintain anesthesia as long as needed.
3. Pain relief: Spinal blocks provide total pain relief, while epidurals provide partial pain relief. Spinal anesthesia is an anesthetic, blocking all sensation, while epidural anesthesia is an analgesic, reducing pain without blocking all sensation.
4. Mobility: Epidurals allow for the pushing required during the second stage of labor, while spinal anesthesia may impede the ability to move legs.
5. Procedures: Spinal anesthesia is often used for genital, urinary tract, or lower body procedures, while epidural anesthesia is often used during labor and delivery, and surgery in the pelvis and legs.

Combined spinal-epidural (CSE) techniques can combine the advantages of both methods, providing quick onset of pain relief with spinal anesthesia and long-lasting relief with epidural anesthesia.

Comparative Table: Spinal vs Epidural Anesthesia

Here is a table comparing the differences between spinal and epidural anesthesia:

In summary, the main differences between spinal and epidural anesthesia are the placement of the needle, the volume and medication injected, the timing of pain relief, and the use of a catheter. Both types of anesthesia share the same risk profile and provide temporary block of neural function at a spinal cord level.