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Reviewed/Revised Mar 2022 | Modified Sep 2022
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What is surgery?

Surgery is a medical procedure in which doctors make a cut in your body to treat a disease, injury, or other health problem. Some examples of surgery are taking out a tumor, opening a blockage in your intestine, or attaching a blood vessel in a new place to help blood flow to part of your body.

  • Emergency surgery treats a life-threatening problem right away, such as repairing a burst artery

  • Urgent surgery treats a serious problem within hours, such as removing an inflamed appendix

  • Elective surgery treats a problem that can wait until you're ready to have it fixed, such as replacing a knee joint or removing wrinkles on your face to help your appearance (cosmetic surgery)

Doctors sometimes refer to surgeries as major or minor.

Major surgery usually involves doctors cutting into your belly area, chest, or head. A team of doctors does this surgery in a hospital operating room while you're unconscious. Afterward, you'll usually stay one or more nights in the hospital.

Minor surgery doesn't involve opening up a big part of your body and doesn't usually affect your major organs. One doctor rather than a team may do this surgery in a hospital or other location (such as a doctor's office). Usually, you go home the same day.

If your doctor recommends that you have surgery, you may first want to get a second opinion Getting a Second Opinion Despite many similarities in training, doctors may vary in their opinions about how to diagnose or treat certain disorders. Such differences can occur among the best of doctors. Differences... read more , where you tell another doctor about your health problem and ask how that doctor would treat it. This lets you compare their treatment advice to your regular doctor's advice.

Keyhole surgery

Keyhole surgery is surgery that uses smaller incisions (cuts) than traditional surgery. Doctors do the surgery using a tiny video camera, lights, and surgical instruments inserted into small cuts in your body. Keyhole surgery has advantages compared to traditional surgery, such as:

  • Less pain

  • Less damage to tissue

  • Shorter hospital stay

  • Quicker return to work

Keyhole surgery also has some disadvantages, such as:

  • Surgery takes longer

  • It's more difficult for doctors

  • Pain after surgery may be greater than you expect

Why do doctors do surgery?

Doctors use surgery to find problems, such as to:

  • Get a sample of tissue to look at under a microscope (biopsy)

  • In emergencies, find and treat problems such as bleeding from a wound

Doctors also use surgery to fix problems, such as to:

How is pain controlled during surgery?

An anesthetic is something that blocks you from feeling pain or makes you unconscious. Analgesics are medicines that lessen pain. Before surgery, a doctor or nurse practitioner will give you anesthesia to keep you from feeling pain during the surgery.

Types of anesthesia:

  • Local anesthesia numbs one particular spot—for example, a doctor may inject lidocaine into the skin on your arm before taking off a skin growth

  • Regional anesthesia numbs an area of your body because the medicine is injected into one or more nerves—for example, an epidural during childbirth

  • General anesthesia makes you unconscious by giving you medicine that goes into your bloodstream—during surgery, the doctor giving anesthesia will keep checking your breathing, heart rate, and blood pressure, and you may need a breathing tube or ventilator

What happens before, during, and after surgery?

Before you have surgery, your doctor and their care team will explain what you can expect to happen before, during, and after the operation.

Getting ready for surgery

Doctors will tell you how to get ready for your surgery. They may have you:

  • Stop eating and drinking 8 hours before surgery

  • Stop drinking alcohol

  • Stop smoking

  • Stop taking certain medicine, such as blood thinners

  • Donate blood in case you need additional blood during surgery

  • Sign a form to show you are agreeing to the surgery and understand the risks (informed consent)

  • Leave jewelry and valuables at home

  • Change into a hospital gown and take off hearing aids, contact lenses, eyeglasses, rings, or other jewelry

During surgery

Doctors will give you anesthesia. If you have local or regional anesthesia, doctors may also give you antianxiety medicine to keep you calm and relaxed during surgery.

Sometimes doctors will put a tube (catheter) into your bladder to collect your urine. You may also have an IV into your arm for medicine and fluid.

If you're having major surgery, you'll be taken to an operating room with medical machines and instruments. The care team usually includes doctors who will do the surgery, a doctor who makes sure the anesthesia is working, nurses, and other health care professionals.

In the Operating Room

The operating room provides a sterile environment in which the operating team can do surgery. The operating team consists of the following:

  • Chief surgeon: Directs the surgery

  • One or more assistant surgeons: Help the chief surgeon

  • Anesthesiologist: Controls the supply of anesthetic and monitors the person closely

  • Scrub nurse: Passes instruments to the surgeons

  • Circulating nurse: Provides extra equipment to the operating team

The operating room typically contains a monitor that displays vital signs, an instrument table, and an operating lamp. Anesthetic gases are piped into the anesthetic machine. A catheter attached to a suction machine removes excess blood and other fluids, which can prevent surgeons from seeing the tissues clearly. Fluids given by vein, started before the person enters the operating room, are continued.

In the Operating Room

After surgery

After the operation, doctors will take you to a recovery room for an hour or two. They'll make sure that you're thinking clearly, breathing well, and have enough medicines to relieve your pain as the anesthesia wears off. Depending on the type of surgery and anesthesia you had, doctors will either let you go home or have you stay in the hospital.

If you go home after surgery, your doctors first make sure you:

  • Are able to drink fluids, urinate, and walk

  • Are free from severe pain, bleeding, and unexpected swelling in the surgical area

  • Schedule a follow-up visit with your doctor

  • Understand how to take your medicines

  • Know which activities to avoid, such as climbing stairs or driving a car

  • Know which symptoms are signs that you should call the doctor

If you stay overnight in the hospital after surgery, doctors will:

  • Use one or more medical devices, such as a tube that drains urine from your bladder or a small device on a finger that measures the oxygen level of your blood

  • Give you medicines to relieve pain and sometimes stool softeners to help prevent constipation (trouble passing stool)

  • Make sure you get healthy food to help you heal and lower the chance of infection, and sometimes give liquid food through a tube in your throat if you can't eat solid foods yet

  • Check you for possible problems such as fever or blood clots

How safe is surgery?

The safety of surgery depends on the type of surgery and how healthy you are. The risk of death in surgery increases with age. Emergency surgery is usually riskier than planned surgeries. Even when there are risks to surgery, they may be outweighed by the potential benefits.

Complications that can develop after surgery include:

Call your doctor if you have medical problems after surgery.

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