Spinal Anaesthesia - Difference From Epidural Anesthesia

Difference From Epidural Anesthesia

Epidural anesthesia is a technique whereby a local anesthetic drug is injected through a catheter placed into the epidural space. This technique has some similarity to spinal anesthesia, and the two techniques may be easily confused with each other. Differences include:

• The involved space is larger for an epidural, and consequently the injected dose is larger, being about 10–20 mL in epidural anesthesia compared to 1.5–3.5 mL in a spinal.
• In an epidural, an indwelling catheter may be placed that avails for additional injections later, while a spinal is almost always a one-shot only.
• The onset of analgesia is approximately 15–30 minutes in an epidural, while it is approximately 5 minutes in a spinal.
• An epidural often does not cause as significant neuromuscular block unless specific local anesthetics are used which block motor fibres as readily as sensory nerve fibres, while a spinal more often does.
• An epidural may be given at a cervical, thoracic, or lumbar site, while a spinal must be injected below L2 to avoid piercing the spinal cord.