The Department of Anesthesia, Critical Care and Pain Medicine at Massachusetts General Hospital offers answers to patients' frequently asked questions about anesthesia.

Patients and families often have many questions about what to expect and how to prepare for anesthesia during a surgical procedure. As always, it is recommended to also review your questions with your surgeon and anesthesia provider.

What is anesthesia?

Anesthesia is a group of medical treatments that allow surgical procedures to be performed safely, effectively and comfortably. It causes the loss of feeling, with or without the loss of consciousness. The purpose of anesthesia is to relieve pain, to reduce awareness and to keep your body motionless during a procedure.

There are different types of anesthesia, all of which use a combination of medications administered in different ways.

General Anesthesia: General anesthesia is for the whole body. Medications are given to you as a gas that you breathe or through an IV, a tube put inside a vein in your arm or leg. Many operations require general anesthesia. 

Regional Anesthesia: Regional anesthesia is for a specific, large area of the body. A regional anesthetic may be combined with another type of anesthesia. The different types of regional anesthesia include the below.

  • Peripheral Nerve Blocks, or injections next to peripheral nerves. Nerve blocks can be used on many parts of the body. For example, the anesthesia team may be able to block pain from shoulder or arm surgery by injecting medication in the neck, where it numbs the nerves that go into the shoulder. Peripheral nerve blocks are often used with conscious sedation or general anesthesia
  • Spinal Anesthesia, or injections inside your spinal fluid where it numbs the nerves. Spinal anesthesia is most often used for surgical procedures involving the lower body
  • Epidural Anesthesia, or injections to numb the nerves coming out of the spine. This is done by inserting a small plastic tube into the back which stays in place while the medications are given continuously or by small repeated doses. Epidural anesthesia is most often used for surgical procedures involving the chest or lower body and may be left in place after the surgery to provide continued pain control.

Local Anesthesia: Local anesthesia either places medication on the skin or injects it to block pain in a small area of the body. Local anesthesia is most often used for procedures that are on or just under the skin. Local anesthesia can be safely administered by surgeons, dentists and other clinicians who are not anesthesia providers

Conscious Sedation and Monitored Anesthesia Care (MAC): Also called twilight sleep, procedural sedation or just sedation. Medications are used to make you sleepy and calm. Sedation may also provide mild pain relief and reduce your awareness of what is going on around you. Many procedures, such as colonoscopies, are often done with sedation administered by a registered nurse (RN) under the direction of a physician. An anesthesia or nurse will be there to monitor during the procedure.

During surgery, the anesthesia team is responsible for closely watching your vital functions so that the surgeon can focus on the operation.

What are the different benefits?

General anesthesia

  • Allows for your anesthesia provider to control your breathing more easily
  • Can be used with muscle relaxants to keep you very still during certain procedures
  • Puts you to sleep so you will not be aware of anything or feel pain during surgery

Watch this video for more information

Regional anesthesia

  • Blocks pain to specific body parts without putting you to sleep
  • Can be used along with general anesthesia to provide long-lasting pain relief during and after surgery
  • It is safer to use during pregnancy, as the medication stays near where it is injected
  • Uses lower doses of medication than general anesthesia

Watch this video for more information

What are the risks of general anesthesia?

General anesthesia is usually very safe, with some common side effects that are temporary. Serious or permanent effects are rare. If you have any questions about potential risks, please consult with your doctor and anesthesiologist.

Common side effects of general anesthesia include:

  • Body aches
  • Constipation
  • Dry mouth
  • Grogginess or confusion
  • Injury to your lips
  • Nausea or vomiting
  • Shivering and feeling cold
  • Sore throat

Less common side effects of general anesthesia include:

  • Damage to your teeth
  • Delirium or cognitive dysfunction (mental fuzziness)
  • Eye injury or loss of vision
  • Slow wake-up

You may have a higher or lower risk for side effects or complications based on your health. Your anesthesia team will do everything possible to manage your risks and keep you safe and comfortable during your surgery.

Watch this video for more information

What are the risks of regional anesthesia?

The side effects of regional anesthesia depend partly on what body part is affected. If you have any questions about potential risks, please consult with your doctor and anesthesiologist.

Common side effects of regional anesthesia include:

  • Soreness or bruising from the injection
  • Failure of the medication, though this would be rectified before the procedure starts

Less common side effects of regional anesthesia include:

  • Spinal headache, also called post dural-puncture headache, which can happen if a spinal or epidural needle accidentally punctures a sac in your spine
  • Bleeding, sometimes leading to a build-up of clotted blood called a hematoma

You may have a higher or lower risk for side effects or complications based on your health. Your anesthesia team will do everything possible to manage your risks and keep you safe and comfortable during your surgery.

Watch this video for more information

What can I do to help the anesthesia?

You can assist by making sure your anesthesia providers have all the information they need before your surgery. This will also help reduce the chance of your surgery being delayed or rescheduled. You may also be asked to have an anesthesia screening before surgery. This may be done over the phone or in a clinic. At this appointment, a health care provider will ask you specific questions about your health and medical history. This is important for planning your anesthesia care.

Below are examples of steps that you can take to assist your care team:

  • If asked, please complete all medical tests (such as blood tests, urine tests, electrocardiograms and MRIs) or other medical appointments (with primary care doctor or specialists) prior to surgery
  • Ask your doctor for instructions regarding medications. Some can be taken as usual before surgery, but others should be stopped or taken at a different dose
  • Don't be afraid to speak up and ask questions as well as express concerns to your anesthesia provider

Tell your anesthesia provider about your health and lifestyle, including:

  • Any health conditions you have such as asthma, diabetes or heart disease
  • If you or anyone in your family has had a bad reaction to anesthesia in the past
  • Allergies to food, medications or latex
  • Any routine prescription or over-the-counter medications
  • Any routine herbal or nutritional supplements
  • Any recent changes in your health including recent illnesses as well as new symptoms, like trouble breathing or chest pain

Watch this video for more information on how to prepare for general anesthesia

Watch this video for more information on how to prepare for regional anesthesia

Will my anesthesia provider have my medical records?

It depends. Usually, your anesthesia provider will have access to the same records as your surgeon. At Mass General, they will also have records from other doctors and hospitals that are part of Mass General Brigham. They usually won't have records from external doctors and hospitals unless you or your care team requested a copy.

It is recommended to keep a list of all the below. If you are scheduled for a preoperative anesthesia screening in a clinic or over the phone, give this list to the person you talk to. Otherwise, give the list to your surgeon.

  • Any previous surgeries you have had. Include the type of surgery, the year and the name of the hospital where it was administered
  • Any medical tests or imaging (including the type of test, the year and the administering hospital)
  • The name and phone number of your primary care provider and any specialist doctors you have seen

We also recommend that you call your surgeon's office a week before your surgery to make sure they have your medical records.

Do I need to fast (not eat or drink) before my procedure?

Anesthesia medications make it hard for you to cough, and they may make you vomit during your surgery. If there is anything in your stomach and you vomit, you may breathe the vomit into your lungs which can cause serious complications. The general rule is to stop eating eight hours before surgery and to stop drinking clear liquids two hours before surgery. Clear liquids include water, juice and coffee or tea without milk. Please refrain from chewing gum at least two hours before your surgery.

We recommend that you drink plenty of water each day throughout the week before your surgery. If you are diabetic, ask your doctor if it is okay to bring a can of clear juice to the hospital in case you feel sick on the morning of surgery.

You may get different instructions from your care team about when to stop eating and drinking depending on your health and the type of surgery. Always follow the instructions that your doctor gives you. Otherwise, your surgery may be delayed or rescheduled.

Should I stop taking or change the dose of my medication before my procedure?

Some medications and vitamins should be taken as usual the morning of your surgery, while others should be stopped altogether or taken at a different dose. You will be given specific directions about your medications based on your health and the type of surgery. Always follow the instructions that your doctor gives you. Otherwise, your surgery may be delayed or rescheduled.

Should I temporarily stop smoking before my procedure?

You can reduce the chance of serious surgical complications by quitting smoking, even temporarily. The effects of smoking on the body are not limited to your lungs. It has also been linked to problems with wound healing and increased risk of infection at the surgical site. Furthermore, anesthesia is much more predictable and safer in those who do not smoke. This is because the heart, lungs and blood vessels function better in non-smokers.

The benefits of quitting begin the day you quit. Improved heart and lung function begins as early as 12 hours after quitting. In less than a day, carbon monoxide and nicotine levels drop and blood flow improves. The longer you quit, the more benefits you gain.

Can I drive home from the hospital?

After receiving anesthesia, your decision-making and reaction time may be impaired for up to 24 hours. You should not drive during this time. You should plan to have someone meet you at the hospital who will make sure you get home safely.

What should I avoid wearing on the day-of surgery?

In order to ensure a safe and effective procedure, it is recommended that you do not wear any of the following:

  • Hair products (gel, mousse, hair spray, etc.)
  • Jewelry
  • Lotion
  • Makeup
  • Nail polish
  • Perfume

In order to monitor oxygen levels in your blood, we apply a special sensor to your fingertip, which works by passing a light through your nail and skin. This sensor may be less effective in the presence of nail polish or acrylic nails, especially when dark colors are used. Additionally, cosmetics may be flammable and increase the risk of burns, as various heat sources are used during surgery. Also, eye makeup, especially mascara, may cause eye injury while you are under anesthesia, since you will not have your blink reflex.

Why did my doctor ask me about my alcohol and drug use?

Alcohol and certain drugs can alter how effectively the anesthesia works as well as interact with anesthesia medications to cause health problems, including fatal heart complications. We encourage you to answer questions from your anesthesia provider as honestly as you can so that we can keep you safe.

Why did my doctor ask me about other injuries, rashes, cuts and blisters?

Each surgical procedure requires you to be in a specific position to give the surgeon the best access to the surgical site. Your team will always make sure that your body is supported and padded. If you have sensitive areas, your care team can also take extra measures to protect them. For example, if we know you have a bad shoulder, we won't extend your arm very far.

Some cuts and rashes can pose a big risk for infection, especially if they are near the surgical site. This can lead to serious health complications and a longer hospital stay. To prevent this, we will look at any skin problems you have and decide if they need to be treated before your surgery.

Who will give me anesthesia?

At Mass General, your anesthesia will be supervised by a board-eligible anesthesiologist, which is a doctor who has completed advanced training in anesthesia. The anesthesiologist will often work with either a certified registered nurse anesthetist (CRNA) or an anesthesia resident.

CRNAs are registered nurses (RNs) who have critical care experience and have completed graduate training in anesthesia. Anesthesia residents are doctors who have completed medical school and are doing their advanced training in anesthesia under the supervision of anesthesiologists.

Anesthesiologists, CRNAs and residents are all anesthesia providers, and together they make up your anesthesia team. All of them are highly trained in advanced life support, resuscitation and airway management. Local anesthesia alone does not require an anesthesia provider and is usually given by the same doctor who will do the procedure.

What should I expect before the procedure?

Anesthesia Screening

You will likely be scheduled for an anesthesia phone screening before your surgery or procedure. These appointments are often referred to as the pre-procedural evaluation (PPE) or preadmission testing.

Before your screening, you should create a Patient Gateway account or ask your Mass General primary care provider to create one for you. Then, you should log in and complete the necessary online forms as instructed by your provider.

During your phone appointment, you will be asked about your medical, medication and anesthetic history. You will also review instructions for when to stop eating and drinking before the procedure and which medications to change or stop.

An anesthesiologist will contact you after your initial phone appointment if there are further questions about the best anesthesia plan for you.

On the Day of Surgery

Your doctor's office will tell you when to arrive at the hospital on the day of your surgery or procedure. On the day of your surgery, please go to the Center for Perioperative Care (CPC) on the 3rd floor of the Wang building. Once checked in, you will be taken to a pre-procedure waiting room. Your family members can wait here with you.

Prior to your procedure, you will:

  • Be asked to change into a hospital gown and remove dentures or eyeglasses
    • If you are not staying overnight in the hospital, you will be assigned a locker to store your clothes and other items
    • If you are staying overnight, you will give your clothes and other items to someone who will place everything in a labeled bag and deliver it to your hospital room
  • Be given very tight socks (compression stockings) to wear as protection from the unlikely event of a blood clot
  • Be asked for your name and type of surgery by different staff members—this is a normal safety measure to make sure you receive the right care
  • Have the area of your body where you are having surgery marked
  • Have your vital signs checked and receive some tests, such as a finger prick to check blood sugar
  • Be asked to open your mouth. They will check for any loose or chipped teeth, and will get an idea of how easy it will be to put in a breathing tube if you need one
  • Meet with your anesthesia team to have an opportunity to ask them questions, receive medication and receive an IV, which is a thin tube that goes inside one of your veins and provides you with fluids

Watch this video for more information on what to expect before general anesthesia

Watch this video for more information on what to expect before regional anesthesia

What should I expect during the procedure?

When you are brought to the operating room (OR), the team will place monitors on you to check your heart rate, blood pressure and oxygen levels. You may notice safety checks being done before the surgery starts. Equipment in the OR is carefully checked and counted before the procedure.

If you receive general anesthesia:

  • You may arrive to the OR awake but will be unconscious once the procedure starts
  • You will not hear or feel anything once you are asleep and you won't remember what happened while you were asleep
  • You may breathe on your own or you may have a tube put in your nose or throat so that oxygen can be given to you
  • An anesthesia provider will carefully monitor your breathing, heart function and how deeply you are asleep during the procedure

If you receive sedation or monitored anesthesia care:

  • You may be drowsy, lightly sleeping or awake and relaxed, depending on the type and amount of medication you receive
  • You will usually receive local or regional anesthesia along with sedation, so you should not feel any pain. Depending on the procedure, you may still be able feel pressure or motion
  • You will breathe on your own during the procedure, usually through an oxygen mask or tube under your nose
  • If you are lightly sedated, you may or may not hear and see things happening in the room during the procedure
  • After the procedure, you may or may not remember things that happened while you were sedated

Watch this video for more information on what to expect during general anesthesia

Watch this video for more information on what to expect when you get a peripheral nerve block

Watch this video for more information on what to expect when you get a spinal or epidural for labor

What should I expect after the procedure?

When your surgeon has finished the operation, your anesthesia provider will stop any medication that kept you asleep in order to wake you up. This is called emergence and it is very different than waking up from normal sleep. You may feel groggy, confused or cold for a short time. Some people become agitated or tearful as they wake up, but this doesn't usually last very long and most people don't remember it.

Depending on your body and the medication you received, you may or may not remember parts of this time. Noises, like people talking, are often the first thing that patients remember. This is normal. You will then be transported to the recovery room.

Possible symptoms of recovery include:

  • Awareness of some pain, which you should let the nurses know about as soon as you begin to feel it
  • Nausea, which can be treated by medication or other methods
  • Cold or chills
  • Sore throat, if you had a breathing tube during surgery

Before you leave the recovery room, you will be evaluated to ensure that you are ready for discharge. We will check your vital signs, assess your pain level and make sure that any nausea is controlled.

If you are being discharged on the same day, a staff member will return your belongings and give you discharge instructions and prescriptions from your surgeon. Your family can join you at this point, they are waiting in the hospital. If someone is going to pick you up, a staff member will call them.

If you are going to be admitted to the hospital after the surgery, please be aware that you may be in the recovery room for several hours until a room on the floor is available. Again, your family can join you at this point.

Watch this video for more information on what to expect after general anesthesia

Watch this video for more information on what to expect after receiving a nerve block

I have had side effects in the past after anesthesia. Will it happen again?

If you have had side effects from anesthesia in prior procedures, please inform your anesthesia provider prior to surgery.

Your anesthesia provider will ask you about prior experiences with anesthesia to understand how your body reacted in the past. Make sure to share your history of anesthesia care, your expectations and your concerns. In particular, please inform your anesthesia provider if you are prone to motion sickness and if anyone in your family has ever experienced complications with anesthesia.

Despite our best efforts, some patients still experience unpleasant side effects of anesthesia. The good news is that we have medications to treat these symptoms if they occur, and we will work with the nursing team in the recovery room to keep you comfortable and safe.