Regional Anesthesia
What is regional anesthesia?
Regional anesthesia involves making a particular region of your body numb, or insensitive to pain. The region is usually large, like a limb, or your lower body. Anesthesiologists may refer to this as "giving a block," because they inject local anesthetics near a nerve or nerve bundle to block sensation. For surgical procedures, this is the most commonly used alternative to general anesthesia.
Particular forms of regional anesthesia include spinal, epidural, arm or shoulder blocks.
Why would my anesthesiologist want to use or recommend regional anesthesia?
For some patients, or some operations, it may be the most convenient, the best tolerated and the safest way of providing anesthesia. Factors include:
- Your health history or current state of health.
- Your anesthesiologist's plan to avoid stress of general anesthesia on certain body organs.
- Type of surgical procedure.
- Arm or leg surgery, even total joint replacements.
- Lower body surgery, like hernia or urinary procedures.
- Your desire to avoid loss of control or loss of consciousness.
- Your desire to avoid side effects of general anesthesia, such as nausea or sore throat.
- Your desire for more prolonged pain relief after surgery.
Both types of anesthesia have advantages. Can I receive both?
Your anesthesiologist may offer a plan that combines the two types of anesthesia. In this situation, the regional anesthesia portion may focus more on relief of pain during your recovery.
Are spinal and epidural anesthesia the same?
Both types of anesthesia are used to numb the lower half of the body for many surgical procedures. Both begin with a needle placement into one of the spaces between the backbones of the spine, and both use a combination of local anesthetic and narcotic drugs to achieve their effects. Health professionals use the two terms to distinguish exactly where the drugs are placed near the nerves. Epidural means "above the dura," which is the outermost layer that covers the spinal cord and nerve roots. Spinal and epidural anesthesia have different effects. Spinal anesthesia affects more nerves that control movement (motor nerves) than epidural, while both affect nerves that control pain and feeling (sensory nerves).
Usually the epidural anesthesia involves a plastic tube (catheter) being left in place near the target nerve roots, so anesthetic medication for pain relief can be given directly while you are recovering.
How do I receive spinal or epidural anesthesia? Does it hurt?
First, monitors will be placed on your body to check vital signs and you will have an IV started. If possible, you will be given medicine to help you relax. The anesthesiologist will position your body to make it easier to place the needle in the space between backbones (vertebrae). You can be placed sitting up or lying on one side. Support staff may help hold you in position.
The anesthesiologist applies disinfectant and a sterile drape to your lower back. They will inject local anesthetic under your skin. You will feel this, but it will last for only a few seconds as it begins to numb the area. Most patients say that this was the most uncomfortable part of their procedure.
Once the area is numb, the anesthesiologist will insert and slowly advance the needle. During this period, staff will remind you to relax and not move. If you feel anything, tell the anesthesiologist, and don't try to move away. After the needle is in place, anesthetic medication is injected, or the epidural catheter described above is inserted, followed by medication. The placement needle is then removed.
As the medication begins to work, most patients report a warm sensation in their legs or feet. As it progresses, numbness will set in. Your legs will feel weak, then not move as you command them. The extent of the numbness depends on the surgical procedure and the medication used for the anesthesia. This also determines how long the anesthesia effect will last. Feeling and strength return gradually to your legs as the medication is used up.
What are the risks of spinal or epidural anesthesia?
Many people fear that the needle penetrates the spinal cord and can cause paralysis. Regional anesthesia places needles and medications near spinal nerve roots or peripheral nerves; the spinal cord is not entered.
As with general anesthesia, some side effects can occur that vary with individual patients. Some have a short-term backache, and occasionally patients feel a headache. Your anesthesiologist is prepared to discuss regional anesthesia, including the potential risks, side effects and their treatments with you before proceeding.
I have been told that I have to lie flat for several hours after spinal anesthetic. Is that true?
No. Previously, anesthesiologists felt that lying flat would help prevent the chances of getting a headache. Improved techniques and equipment reduce the chances of headache today, so you will have some freedom of movement afterward.
What about arm or shoulder blocks?
The process is very similar to the one described above for spinal anesthesia. A needle is placed close to the nerves that control the arm or shoulder, then those nerves are surrounded with anesthetic medication to block pain sensation.
Do I always have the option of regional anesthesia?
Some surgeries cannot be performed successfully using regional anesthesia alone. Your health history or current state of health may not make it safe for us to offer you this type of anesthetic. Reasons may include bleeding disorders, previous back surgery, unique anatomy of your back, or if you are unable to remain in position while anesthesia is delivered.