Epidural anesthesia is a method used to eliminate pain during certain procedures or surgeries. In this form of anesthesia, medication is injected inside the spinal column with a needle or thin tube.
An epidural, as the procedure is commonly called, is usually used for procedures performed below the rib cage. It is often the preferred way to reduce pain during childbirth. It can also be used for pain control after surgery or childbirth.
Epidural anesthesia is an attractive alternative to general anesthesia for a person who has medical complications that might make it difficult to tolerate or recover from general anesthesia.
A needle or special tube is inserted through the skin of the back into the spinal column until it touches, but not pierces, the sac that contains the spinal cord, then withdrawn slightly before the medication is injected. Thus, the medicine is delivered just outside the sac that contains the spinal cord. The medication acts on nerves that come from the spinal cord and carry pain messages to the brain.
An epidural is different from spinal anesthesia, a procedure in which the medication is injected inside the sac that contains the spinal cord. Epidurals are usually preferred for childbirth and are often better for pain control. An epidural requires more medication and takes longer to work than a spinal, but is less likely to cause headaches and low blood pressure.
Epidural anesthesia may be given as a one-time injection with a needle. However, sometimes, if a lengthy procedure is planned or if considerable pain after surgery is foreseen, the healthcare professional may place a tiny tube into the spinal column in place of the needle, and leave it there as a port to inject more medication during and shortly after the surgery.
The medication stops the sensation of pain and paralyzes the muscles, usually only below the rib cage. The amount of medication used can affect how far the numbness and paralysis extend through the body. The individual is generally awake during the procedure. Sedatives can be given if the person has anxiety.
The oxygen levels in the blood, pulse, blood pressure, and other functions are carefully monitored during and after the procedure. Fluids are usually given through an intravenous line (IV) to prevent dehydration and low blood pressure. If a tube is inserted into the spinal column, it is removed when no longer needed.
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