Types of Anesthesia Used During Surgery

Anesthetist administering gas to patient
Science Photo Library - Ian Hooton/Brand X Pictures/Getty Images

Anesthesia is the administration of medication to allow medical procedures to be done without pain and, in some cases, without the patient being awake during the procedure. It is used in a wide range of procedures, from highly invasive surgeries, such as open-heart surgery, to minor procedures such as having a tooth extracted.

There are four types of anesthesia: general, regional, local, and monitored anesthesia care (MAC). Several different medical professionals are able to administer these for a variety of purposes.

General Anesthesia

This is the strongest type of anesthesia and is most commonly used for surgeries that would otherwise be unbearably painful, such as knee replacements and heart surgeries. With general anesthesia, you are typically given a combination of medications through a mask or IV. This will render you unconscious.

General anesthesia not only makes you unaware, but it paralyzes your muscles—including those that make it possible to breathe. For this reason, you will require a ventilator to do the work of the diaphragm and other muscles that help make it possible to inhale and exhale.

Your anesthesia provider will continuously monitor your vital signs, such as heart rate, blood pressure, and breathing, during your procedure. When the surgery is done, other medications are used to reverse the effect of the anesthesia. You will also be monitored in this recovery phase.

Regional Anesthesia

Regional anesthesia is provided by injecting specific sites with a numbing medication. This may be done with a needle or via a flexible catheter line through which anesthetics and other medications can be administered as needed.

With this type of anesthesia, only the body part being operated on is numbed, which means you are awake—that is, sedated, but still conscious—during the procedure. The anesthetic works on the nerves, causing numbness below the injection site. Even though you will be awake, you will continue to be monitored throughout your procedure.

Epidurals, or spinal blocks, in which medication is administered in your back, are examples of regional anesthesia. They are often given during labor and childbirth, and during surgeries on your limbs to block sensation in your arms and legs. Though they have different uses, they are commonly given in childbirth to restrict pain medication to one area of the body in an effort to prevent a fetus from being exposed to sedatives that may be harmful to them.

Epidurals provide continuous pain relief as long as medications are continuously running and there are no side effects. Spinal blocks are given with a finer needle to the spinal sac, with the medication entering the cerebrospinal fluid.

Another example of regional anesthesia is a peripheral nerve block, which may be given in the shoulder/arm, back, or leg regions. If you are having hand surgery, your anesthesia may use a peripheral nerve block to numb your entire arm and hand, or the numbness may be mostly limited to your hand.

Local Anesthesia

This type of anesthesia is typically used to numb a small site for minor procedures, such as filling a cavity or for a skin biopsy. During the administration of local anesthesia, a numbing medication is either applied to the skin as a cream or spray or injected into the area where the procedure will be performed.

If the medication is injected, several small injections are sometimes used. A few minutes after this is complete, the area should be completely numb. If the area still has sensation, additional injections or applications may be given to ensure total numbness.

Monitored Anesthesia Care (MAC)

This is a type of sedation commonly referred to as "twilight sleep." It's usually used for outpatient procedures such as a colonoscopy or cataract surgery and is administered through an IV to make you feel sleepy and relaxed during your procedure.

While you may be heavily sedated, this type of anesthesia is different from general anesthesia because you are not chemically paralyzed, nor do you require assistance with breathing. Still, your vital signs are closely monitored to make sure you are stable throughout the procedure.

This type of anesthesia wears off in as little as 10 minutes. Depending on the medications used and the doses given, you may or may not remember the procedure.

The type of anesthesia used typically depends on the type of surgery, your state of health, the length of the procedure, and the preferences of your anesthesia provider and surgeon.


Just as no surgery is risk-free, no anesthesia is 100% safe either. The main side effects of MAC are nausea and vomiting , while side effects of local anesthesia can include soreness where the anesthetic was injected and an allergic reaction to the anesthetic.

General anesthesia can also involve minor side effects like nausea, vomiting, confusion, and sore throat, as well as the following rare, but serious, risks:

Postoperative cognitive dysfunction: Often referred to as "brain fog," this can lead to long-term memory and learning problems.

Malignant hyperthermia: This is a serious reaction to anesthesia that can occur during surgery, causing a quick fever, muscle contractions, and even death. If you or a family member has ever experienced this condition during surgery or have ever had heatstroke, you're at a higher risk, so it's very important to talk to your doctor about this.

Breathing problems during or after surgery: General anesthesia can be a bigger risk if you suffer from obstructive sleep apnea, a condition in which you stop breathing while you sleep. If you have sleep apnea, anesthesia can cause the throat to close up during surgery, which can make it more difficult to regain consciousness and begin to breathe normally after your procedure.

Regional anesthesia carries some risks as well, including:

  • Allergic reaction to the anesthesia used
  • Bleeding around the spinal column
  • Difficulty urinating
  • Drop in blood pressure
  • Infection in your spine
  • Nerve damage
  • Seizures
  • Severe headache

Some of these side effects, such as nerve damage and seizures, are rare, but always talk to your doctor if you have concerns about any potential effects.

Questions to Ask Your Anesthesia Provider

There are several types of medical professionals who are able to provide anesthesia, including physicians (anesthesiologists), nurse anesthetists, dentists/oral surgeons, and anesthesiologist assistants. The level of training varies between different types of providers, with anesthesiologists having the highest level of training.

Before you decide whether to have anesthesia with your procedure or what type of anesthesia you prefer to get, find out the answers to key questions so you can have the safest experience possible. Examples include asking about whether you should eat or drink anything before the procedure, how you might feel coming out of anesthesia, how long you might need to stay at the hospital, and if you should plan for someone should accompany you to and take you home from the hospital.

Make sure your anesthesia provider is well informed about your health, allergies, medications, and other issues, such as personal or family medical history or occupational concerns that may affect treatment choices. There are certain risks that can be avoided with an open conversation prior to a procedure, so you should feel comfortable being candid about your medical history and any previous surgeries you may have had.

Was this page helpful?

Article Sources

Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial policy to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Society of Anesthesiologists. General anesthesia.

  2. American Society of Anesthesiologists. Regional anesthesia.

  3. American Society of Anesthesiologists. IV/Monitored sedation.

  4. American Society of Anesthesiologists. Anesthesia risks.

  5. American Society of Anesthesiologists. Local anesthesia.

  6. MedlinePlus. Anesthesia - what to ask your doctor - adult. Updated September 3, 2018.

  7. American Society of Anesthesiologists. Anesthesia 101. Anesthesia care team.

  8. American Society of Anesthesiologists. Eight things to tell your physician anesthesiologist before surgery. Updated March 11, 2019.

Additional Reading