Anesthesia is the use of medicine to keep you comfortable, safe, and as pain-free as possible during surgery or a medical procedure.

There are four main types of anesthesia:

1. Local anesthesia numbs just a small part of the body.
2. Regional anesthesia, such as nerve block, spinal or epidural anesthesia numbs a larger part of the body.
3. Monitored anesthesia care is intravenous sedation where you may be awake but in a more relaxed state
4. General anesthesia produces unconsciousness. You are asleep throughout the procedure.

 Local anesthesia numbs only the part of the body where you will have surgery. Anesthetic medicines are injected or applied topically (to the surface of the skin, nose or mouth) to temporarily block nerves in the surgical area. This type of anesthesia is used for minor (simple) procedures. Since local anesthesia affects just the nerves in the surgical area and not your brain, you will be awake during the procedure.

 Regional anesthesia eliminates feeling in a larger part of the body. It blocks the spinal cord or groups of nerves so pain signals cannot reach the brain. This type of anesthesia is used for peripheral procedures, such as surgery to the abdomen, pelvis, or arms or legs. You may be awake during the procedure but you may be given medication that will make you feel relaxed or sleepy. The type of regional anesthesia and the type and amount of anesthetic medicine used will determine how long the anesthesia lasts and the specific area of your body that will be affected.

Common types of regional anesthesia:

• Spinal anesthesia is an injection of anesthetic into the spinal canal in your lower back.
• Epidural anesthesia is an injection of anesthetic into the epidural space just outside, not in, the spinal canal.
• Nerve block anesthesia is an injection of anesthetic near a group of nerves to temporarily numb a part of the body such as an arm or leg.

 Monitored anesthesia care (MAC) is intravenous (through the vein) sedation. You may still be awake during the procedure, but you will be in a more relaxed state. Local anesthetic may also be used at the surgical site. This type of anesthesia is used for less invasive (not deep into the body) surgery.

 General anesthesia is needed for major operations and temporarily produces unconsciousness so your brain does not perceive any pain signals. It involves both intravenous and inhalational agents (gases that you breathe). With this type of anesthesia you will be completely asleep. Most of our cases at City of Hope involve a general anesthesia.