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Gastric Bypass: Before Your Surgery

What is a gastric bypass?

A gastric bypass (also called Roux-en-Y gastric bypass) is surgery to help you lose weight. It does this in two ways. First, it makes the stomach smaller. Second, it changes the connection between the stomach and the intestines. These changes help you eat less and feel full sooner.

This procedure can be done in two ways:

  • By making several small cuts and using small tools and a camera to guide the surgery (laparoscopic approach).
  • By making one cut (open approach).

The laparoscopic approach is used most often.

You will be asleep during the surgery. The doctor will separate the upper part of your stomach from the rest of your stomach. This forms a small pouch. This new pouch will hold the food you eat. The doctor will connect the new stomach pouch to the middle part of your small intestine. Then the doctor will close the incisions with stitches. The incisions leave scars that fade with time.

After the surgery, the food you eat will go from the small pouch to the middle part of your intestine. Food will no longer go through the lower part of your stomach or the first part of your intestines.

You will stay in the hospital 1 or more days after the surgery. In a laparoscopic surgery, most people can go back to work or their usual routine in about 2 to 4 weeks. In an open surgery, it takes 4 to 6 weeks to get back to usual routines.

How do you prepare for surgery?

Surgery can be stressful. This information will help you understand what you can expect. And it will help you safely prepare for surgery.

Preparing for surgery

  • You may need to follow a clear liquid diet for several days before surgery. Your doctor will tell you how to do this.
  • Be sure you have someone to take you home. Anesthesia and pain medicine will make it unsafe for you to drive or get home on your own.
  • Understand exactly what surgery is planned, along with the risks, benefits, and other options.
  • If you take aspirin or some other blood thinner, ask your doctor if you should stop taking it before your surgery. Make sure that you understand exactly what your doctor wants you to do. These medicines increase the risk of bleeding.
  • Tell your doctor ALL the medicines and natural health products you take. Some may increase the risk of problems during your surgery. Your doctor will tell you if you should stop taking any of them before the surgery and how soon to do it.
  • Make sure your doctor and the hospital have a copy of your advance care plan. If you don't have one, you may want to prepare one. It lets others know your health care wishes. It's a good thing to have before any type of surgery or procedure.

What happens on the day of surgery?

  • Follow the instructions exactly about when to stop eating and drinking. If you don't, your surgery may be cancelled. If your doctor told you to take your medicines on the day of surgery, take them with only a sip of water.
  • Take a bath or shower before you come in for your surgery. Do not apply lotions, perfumes, deodorants, or nail polish.
  • Do not shave the surgical site yourself.
  • Take off all jewellery and piercings. And take out contact lenses, if you wear them.

At the hospital or surgery centre

  • Bring a picture ID.
  • The area for surgery is often marked to make sure there are no errors.
  • You will be kept comfortable and safe by your anesthesia provider. You will be asleep during the surgery.
  • The surgery will take about 2 to 3 hours.
  • If you're having an open surgery, you may get an epidural catheter. This is a tiny tube that puts pain medicine into the area in your back around your spinal cord. The epidural will prevent belly pain after surgery.

When should you call your doctor?

  • You have questions or concerns.
  • You don't understand how to prepare for your surgery.
  • You become ill before the surgery (such as fever, flu, or a cold).
  • You need to reschedule or have changed your mind about having the surgery.

Where can you learn more?

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