This gastric bypass overview aims to explain the basics of what a gastric bypass procedure is. It will also run through some of the common reasons for having any sort of weight loss surgery. These reasons apply both generally as well as specifically for a gastric bypass.
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Why have a gastric bypass ?
In general, weight loss surgery is an increasingly popular and effective method in tackling obesity. The medical name for this area of surgery is bariatric surgery. The medical name for a gastric bypass is a roux-en-y bypass. This page specifically looks at the gastric bypass procedure, which aims to create substantial and sustained weight loss by reducing the size of the stomach as well as the length of the digestive tract. Therefore, there will be a reduction in the amount of food you can physically eat and the amount of calories your digestive tract can absorb.
This surgery allows up to 70% of excess weight to be lost in the first 2 years and is suitable for people with a BMI of between 30 and 50.
There are different types of surgical techniques that your surgeon can use for your weight loss surgery. Consequently, the technique that they decide to use will depend on a number of factors. These may include:
- The goals you have for your weight loss surgery.
- Your current BMI.
- Your current health status.
- The possible risks you may encounter with each procedure.
This page focuses on the gastric bypass option only. Of course, your surgeon will discuss all of the options available to you. They will explain which technique they think is most appropriate for you and help you to make an informed choice.
What is a gastric bypass operation?
You can find the full details of the gastric bypass surgery in the procedure page. Here, you can find a general overview of what the operation involves.
Your surgeon will use small, 'keyhole,' incisions to reduce the size of your stomach in a gastric bypass. However, as well as this they will also alter the length of your digestive tract. This will reduce the amount of food you can physically eat and the amount of calories your digestive tract can absorb. Because this surgical technique alters the absorption in your digestive tract, you will need to take life-long vitamin and mineral supplements to ensure you get the nutrients you need.
Each operation has specific benefits. Some of the most common reasons that people opt for a gastric bypass over any other surgery include:
- The desire for long term results and weight loss.
- Wanting to be physically restricted from overeating.
- Being fit for major surgery.
- The desire to have a well-established procedure that has been studied for many years.
Why choose to have a gastric bypass operation?
Weight loss surgery in general is an increasingly popular way to tackle obesity. Obesity is medically defined as having a body mass index, or BMI, of 30 or more. You can read more about obesity here. As well as having excess body fat, people who are obese are also at risk of a number of other serious health problems. These can include but are not limited to:
- Type 2 Diabetes
- Coronary heart disease
It is vital to lose weight to reduce your health risks from obesity. Typically, many people can achieve weight loss by doing regular exercise and keeping a healthy and balanced diet. However, this is not the case for everyone. Some people with obesity really struggle to lose their excess weight, even when trying their best with diet and exercise. Others may lose weight at first with diet and exercise but then, after a certain point, their weight loss stops. This can cause their weight to plateau before they reach their desired goal weight. A gastric bypass may be suitable for those people who need further help with their weight loss. It is a good option for those who would like to have definitive surgery to aid their weight loss.
What makes a good gastric bypass candidate?
Suitable candidates for a gastric bypass procedure include:
- People who have a BMI of >30 and a medical condition that can benefit from weight loss (e.g. diabetes or high blood pressure).
- People who have a BMI of >40 with no other medical problems.
- Those who have health issues due to their obesity.
- People with mobility issues as a result of their obesity.
- Those who suffer from depression or low self-esteem because of their obesity.
- People who are well enough for major surgery.
- People who have tried diet and exercise to lose weight with no or limited success.
- Those who are willing to commit to a new, healthier lifestyle after the surgery.
- People with a positive outlook for their surgery.
- Those who have realistic goals for their surgery.
These are some general features that suitable weight loss surgery candidates may have. As a result, it is not a requirement to possess all of these and most people do not. Also, there are relatively few specific factors which make somebody a suitable gastric bypass candidate over another form of surgery. The decision is ultimately yours based on the advice of your surgeon and your preferences.
Having said that, each type of surgery has its own advantages and disadvantages. For a gastric bypass procedure, these include:
- A higher proportion of weight loss in people who have a gastric bypass than a gastric sleeve.
- The effects are well-studied and the technique has been in use for many years.
- A higher risk of complications and involves major surgery.
- A gastric bypass is permanent and unlike a gastric band, is not reversible if problems arise.
- The digestive tract is shortened so lifelong supplements are needed after a gastric bypass.
What can I expect from my gastric bypass consultation?
Your gastric bypass consultation is the first step in your gastric bypass journey. This is an opportunity for you to meet with your surgeon and have a one-on-one interaction. You will be able to discuss all the questions you may have after reading the information you've been provided with. Your surgeon will equally want to explore your treatment goals and ask you about what you're hoping to achieve.
The consultation can last anywhere between fifteen minutes and one hour. Although there are specific elements that your surgeon will want to cover, the consultation is also your chance to become well informed of the procedure. Your BAPRAS surgeon will need to assess whether you are fit and healthy for a gastric bypass operation. They will outline the risks and complications, as well as what the treatment can help you achieve. At the same time, it is important that you gather all the information that you can to ensure that the procedure is definitely the right choice for you.
What will my surgeon want to know?
All medical procedures carry some risks. Your surgeon will want to explore your medical background. This is to ensure that you are a suitable candidate for the procedure. Equally, it enables them to minimise any risks that there may be given your medical history.
It is a good idea to arrive at your consultation with a list of all the medications you take, including the dose and frequency, and the reason why you take them.
Your surgeon may want to explore the following areas of your medical background with you which may include but is not limited to:
- What is your current health status?
- Do you suffer from any serious health conditions?
- What is your past medical and surgical history?
- Do you take any regular medications? (This includes any prescribed, over-the-counter and herbal medications).
- Can you tell me a bit about your previous attempts at weight loss?
- What is your current diet and exercise regimen like?
- Do you smoke, drink alcohol and/or use any recreational drugs?
- Are you prepared to make lifestyle adjustments post-surgery to get the best results possible?
While this may seem like a lot of information to share with your surgeon, it is important that you answer these questions as honestly as possible. Remember, your surgeon is a healthcare professional. They ask these questions in order to determine the best possible treatment plan suitable for you.
In addition to learning about your general health, your surgeon may also wish to explore your weight. They may ask you questions about your previous attempts to lose weight, your motivation for losing weight, and your ability to make lifestyle adjustments post-surgery in order to achieve your goals.
What should I ask during my gastric bypass consultation?
Your consultation can go by surprisingly quickly. We therefore suggest you plan ahead. Think of some of the questions you may have and write them down beforehand. There are lots of resources available on the Medbelle website such as the treatment brochures. As you read this information, make a note of any thoughts you have or concerns that the information raises. This means, at the consultation, you can cover everything you wanted to.
We've made a list of some of the common questions that are raised during consultations. You may wish to ask your surgeon some of these questions, or they may just make you think about what you would like to ask.
- Are my goals realistic?
- What can I do to ensure I achieve my goals?
- What should my diet be like following surgery?
- How long will my recovery be?
- Will I need to take nutritional supplements following surgery?
- How much weight can I expect to lose?
- What will my scars look like?
- Will the results be permanent?
- Will I be in pain after surgery and how can this be managed?
We hope you look forward to your gastric bypass consultation and take advantage of the opportunity to discuss everything with your surgeon.
How can I prepare for a gastric bypass procedure?
As the time approaches for you to have your gastric bypass surgery, it is entirely normal to feel anxious. Fortunately, there is some preparation that you can follow to help distract yourself. These gastric bypass preparation tips should be followed to give yourself the best chance of a smooth recovery.
If you are a smoker, you can start preparing for your surgery by stopping smoking for at least 6 weeks to 3 months before the procedure. If you smoke, your risk of surgical complications both before and after surgery are increased. Therefore, we must stress the importance of stopping as soon as possible before your gastric bypass.
To help build up your body's strength before surgery, it is important that you try to follow a healthy balanced diet and practice regular exercise. Your surgeon will give you further advice on what you will be able to eat and drink in the lead-up to your surgery. It is likely that you will need to follow a strict post-operative diet which your surgeon will outline for you. They will also advise you on which medications you will and will not be able to take on the day of your surgery.
Preparation is also the key to a relaxed, speedy recovery after your gastric bypass procedure. Below are some things you can do before your surgery to make your recovery as easy as possible.
Household work can sometimes involve a great deal of physical effort. During your recovery, it is important that you do not overexert yourself. Therefore, there are some chores that you may like to get out of the way while you are still fit to do so, before you come into hospital. For example, you may like to take out the bins and do the laundry in advance.
It may also be useful to place some things you know you will need at an accessible level. For example, placing crockery and food items on a shelf or countertop where you will not have to bend down or stretch up. This will prevent you from putting unnecessary stress on your stitches.
You may not feel up to going shopping for some time after your surgery. Therefore, it can be really helpful to do a big food shop to stock up on what you need before your gastric bypass surgery. Some people also like to cook meals and freeze them so that they don’t have to cook during their recovery. Online shopping is another great resource you can make use of. You may like to make yourself familiar with how this works before your surgery if you are unsure. Remember that your diet will have to change for a period of time after your surgery. The specifics of this will be discussed by your surgeon and/or dietitian.
Pets and children
If you have any children or pets, you may like to ask friends and family for some help looking after them during your recovery. Pets and children can be hard work so you should ask for help to avoid overexerting yourself.
You may not be able to drive from 5 to 14 days after your surgery. Your surgeon will be able to give you more specific advice on this during your initial gastric bypass consultation. Because you will be unable to drive, you will have to organise for a friend or family member to take you home from the hospital. If you are struggling with this, we are happy to help arrange a safe way home for you.
Eating and drinking
After the surgery, you will need to reintroduce foods very slowly back into your diet. Your surgeon will give you very precise instructions which you must follow. The general plan involves an initial diet which is limited to clear liquids only, then thicker drinks and soft foods are reintroduced. Eventually solid foods can be reintroduced around 6 weeks afterwards, but in much smaller portions than you may be used to. When you do return to eating a normal diet, it is important that it is a well-balanced, healthy one.
You should select some loose items of clothing to wear during your recovery. Items that zip at the front are usually less restrictive so may be more comfortable. You may also like to wear slide on shoes or sandals for a week or so to prevent any unnecessary bending. This way, you will not put any unnecessary strain on your stitches and enable your body to heal.
You may like to make sure you have spare pillows or cushions around the house. This way, you can rest or sleep propped up. This will likely be more comfortable for you in the first few days after your surgery. In addition it will help reduce or prevent any swelling. Your surgeon will prescribe pain medication if needed, so that any pain you experience should not affect your ability to sleep.
How is a gastric bypass procedure performed?
A gastric bypass procedure usually takes between 1 and 3 hours to perform. Below is a general guide to what you can expect from a gastric bypass procedure and what it usually involves. When you meet with your surgeon, they will be able to give you more specific details on what to expect.
Before your surgery, you will meet with your surgeon. To confirm that you would like to go ahead with the gastric bypass procedure you will have to sign a consent form. We advise that you take your time to read the form carefully. This is in order to ensure that you fully understand all the risks, benefits and potential complications of your surgery. Also, be sure to ask any questions you may have before signing your consent form.
You will also meet your anaesthetist before your surgery. A gastric bypass operation requires you to be under a general anaesthetic. This means that you will be asleep throughout the operation. You will wake up gradually but may feel a little drowsy for a few hours until the general anaesthetic wears off. You may notice a slight impairment to your memory and concentration for a day or so but this will return to normal with time.
There are two methods of performing a gastric bypass procedure. Some surgeons prefer to operate in the traditional way using large incisions. However, most are performed using 'keyhole' incisions which involves inserting instruments through 1-5 small incisions in the abdomen. These incisions will be small, minimally invasive and should therefore leave small scars that heal quickly. Your surgeon will be able to tell you more about the incisions specific to your surgery when you attend your initial consultation. This is because they may be in slightly different positions based on the size and shape of your body.
4. Performing the gastric bypass
After making the incisions with either technique, your surgeon will cut across the top of your stomach which effectively seals it off and forms a pouch. This leaves a structure which is about the size of a walnut and can hold only up to 30mls of food. This is in comparison to a normal stomach which has a capacity of 1 litre, or 1000mls.
The next step involves the surgeon making an incision into the small intestine. This allows it to be attached directly to the newly formed pouch. Therefore, food will then travel into this small pouch of stomach and directly into the small intestine when you start to eat again after the surgery. This results in the food bypassing most of your stomach and the beginning of the small intestine, giving the procedure its name. The food then enters directly into the middle part of your small intestine where it can be processed and absorbed by the body.
5. Closing of incisions
Your surgeon will use sutures (stitches) to close your incisions when the surgery is over and will cover the incisions with a dressing. They may insert drains into your tummy to reduce any swelling. You will have to return to the hospital within 10 to 14 days of your surgery so that your surgeon can remove your stitches and drains (if applicable). The staff at the hospital will give you an appointment for this before you are sent home.
6. Return to the ward
The hospital staff will take you back to the ward when your surgery is complete. You will remain drowsy for a couple of hours before you feel fully awake again. This is because the anaesthetic takes some time to wear off. You may notice a negative effect on your memory and concentration, but this will return to normal within 1 to 2 days. Your surgeon will prescribe appropriate pain medication to manage any pain you may have after your gastric bypass procedure. You can expect to remain in hospital for 1-3 days after your surgery before you are able to return home. During this time, you may have many restrictions or limits on what you can eat and drink. Your surgeon will also start you on the recommend vitamin and mineral supplements.
What can I expect after my gastric bypass procedure?
Knowing what to expect after your gastric bypass operation is an important factor to consider when making your decision on whether to have surgery or not. To help you get a better idea of what to expect, we have put together some information on gastric bypass aftercare that we think you might find useful. The majority of this information is general to all weight loss surgery patients. Your surgeon will be able to give answers to any questions you may have which are specific to you and your surgery.
How will I feel after surgery?
In order to carry out your gastric bypass procedure, the anaesthetist will give you a general anaesthetic. This means that you will be asleep for the duration of the procedure. You will wake up slowly when the surgery is complete. You may feel a little drowsy and confused but this will wear off within a few hours. Your memory and concentration may be affected to 1 or 2 days but this will soon return to normal. If you experience any discomfort or pain after your surgery, your surgeon will prescribe appropriate pain medication to manage this.
When can I go home after my surgery?
You will need to stay in hospital from 1 to 3 nights after your gastric bypass surgery. Before you leave, you will be given an appointment to come back within 10 to 14 days. During this appointment, your surgeon will assess your progress and ensure that you are recovering as expected. If you are experiencing any issues, let your surgeon know at this appointment. Of course, if there is a serious problem or you feel very unwell then you should seek medical advice urgently.
What can I eat after my surgery?
In order to get the best results from your surgery, it is important to try your hardest to introduce regular exercise and a healthy diet. This will involve eating much smaller portions that you are used to, and making sure that you get enough protein and fibre. You will also require some vitamin and mineral supplements as your new, smaller stomach can not absorb enough nutrients from the food that you eat.
For the first few weeks after the procedure, your surgeon will give you specific advice on what you should eat. This usually starts off as just liquids and as your stomach recovers you will be able to build up to more solid foods. After around 6 weeks, you should be able to eat normal foods again.
When can I drive after my surgery?
You may not be able to drive for 5 to 14 days after your surgery. Your surgeon will be able to advise your more specifically on this during your consultation.
Because you will be unable to drive straight after surgery, you will need to arrange for someone to take you home from hospital. You may like to ask a member of your family or a friend. If you struggle to arrange this, please let us know and we can help you to get home safely.
Will I be in pain after my surgery?
Your surgeon will prescribe simple pain relief for approximately the first week after your surgery as this is when you will be in the most discomfort. After this first week, you should be able to switch to over-the-counter pain relief medications. By the third week after your surgery, most of your pain and discomfort should have subsided and you should no longer require pain relief medications.
When can I go back to work after my surgery?
The amount of time you will need to take off work will depend on the type of job that you do. If your job is less active (e.g. office work) then you can probably return 1 to 2 weeks after surgery. If your job requires more physical exertion, (e.g. tennis coach, professional wrestling, labourer, cleaner) you will probably require 3 to 4 weeks off work before you return. In any case, you should avoid even light activities for at least 2 to 4 weeks.
When can I exercise again after my surgery?
After your gastric bypass operation, your surgeon will likely advise that you try to do a little light walking every day to avoid the formation of blood clots. Aside from this however, you should avoid all other forms of exercise for at least 4 weeks after surgery. Aerobic activities can increase swelling. Furthermore, you should hold off on all sexual activity for at least 2 weeks after surgery.
From 4 to 8 weeks after your surgery you can begin to reintroduce light aerobic activities like cycling or swimming. You will also be able to take part in activities that do not involve vigorous movement, such as lifting weights.
From 8 weeks after surgery, all activities and sports should be possible again. Keeping active is an essential part of your new healthy lifestyle post-weight loss surgery and will help you to achieve the best possible results.
How can I look after my scars?
You are are most likely to have several small scars after a gastric bypass procedure, but may have a larger scar instead. Initially, when your wounds heal, your scars will appear pink and a little lumpy. Regular scar care can help to improve their appearance with time.
Scar care can involve daily massage using a scar gel or a moisturiser. You can begin daily scar care as soon as your wounds have fully healed. As your scars get less tender, you can increase the pressure of your massage to smooth out the scar tissue and reduce the lumpy appearance. It is vital that you follow the scar care regime that your surgeon gives to you.
When will I see the final results of my surgery?
It will take some time before you see the final results of your gastric bypass surgery. It can take from 8 to 12 weeks before your body feels back to normal again after surgery. By this point, you will likely have begun to notice some weight loss. Following an appropriate diet and exercise regime, you should continue to lose weight steadily. After a gastric bypass, up to 60% of excess weight can be lost in the first 2 years. Therefore, it is important to remember that this is not a quick fix.
Risks and Complications
What are the main gastric bypass risks and complications?
Every surgery comes with risks and complications. Before you agree to go ahead with your treatment, it is important that you educate yourself so that you can make an informed choice about a gastric bypass operation. If you have any questions, be sure to ask your surgeon at your consultation. To help, we have made a list of the main gastric bypass surgery risks and complications. They include, but are not limited to:
A rare but potentially serious complication from the gastric bypass procedure is a leak from where the stomach is cut to form the pouch. This can cause the stomach contents to irritate other organs and can lead to a severe infection. At Medbelle, we only use highly skilled and experienced surgeons to reduce the risk of leaks and other problems.
After a gastric bypass, you may experience some lightheadedness, bloating, nausea, indigestion and diarrhoea 10-30 minutes after you eat foods that are high in sugar. This is a complication known as dumping syndrome, and may result in an inability to eat sugary foods. The cause of dumping syndrome is food moving from your stomach into your small bowel too quickly as a result of the surgery.
Bleeding & bruising
If bleeding occurs, it often happens during or very soon after surgery. However, it is also possible that you may experience some bleeding up to 2 weeks after your surgery. Bleeding and bruising is often minor. If more severe bleeding were to occur, you may have to go back to theatre for further treatment. This may delay your recovery. In addition, you may have a little more bruising than expected. Despite this, your final results should not be affected.
All types of surgery carry the risk of infection. Your surgeon will do everything they can to reduce this risk. Even if an infection does occur, they tend to be mild and are treatable with a short course of antibiotics. In some cases, infections can become more severe and require you to go back to hospital for treatment.
Below are some signs of infection you should look out for:
- A temperature over 38°C.
- Redness spreading away from your wound site > 48 hours after surgery.
- Yellow/foul-smelling discharge coming from your wound.
- Pus oozing out of your wound.
- Pain that does not respond to pain medication.
If you have any of these symptoms after your gastric bypass surgery it is vital that you seek medical help.
Vitamin & mineral deficiencies
There is a risk of developing vitamin and/or mineral deficiencies when you have a gastric bypass operation. As a result of the surgery, your body is no longer able to absorb enough of the essential vitamins and minerals.
Your surgeon will be able to advise you on exactly which nutrients your body may be lacking after the surgery. In addition, they will advise you on which supplements you need to take to prevent any deficiencies and side effects. These supplements will need to be taken for the rest of your life.
Most gallstones form as a result of high cholesterol levels which are associated with obesity. Therefore, obese people undergoing a gastric bypass operation may already have gallstones. Rapid weight loss as a result of a gastric bypass also increases the risk of gallstones. It also increases the risk of complications associated with gallstones.
They can often cause no symptoms. Therefore, many patients may be unaware that they have gallstones. Sometimes however, gallstones can cause recurring episodes of severe stomach pain. The solution to this problem is gallbladder removal, which includes further surgery.
A gastric bypass will leave you with some small scars as it is usually a laparoscopic operation. This involves inserting a camera and surgical tools through small, keyhole incisions in your stomach. These heal quickly and leave small scars that fade with time. Sometimes, the surgery is carried out via a larger incision into the abdomen. Ask your surgeon for more advice on your scars and how best to look after them after surgery.
There is always the risk that you may not be happy with the results of your surgery for aesthetic reasons. For example, as a result of weight loss you may notice excess skin that you do not like the look of. Your surgeon will be able to advise you on what your options would be if this were the case.
General surgical complications
There are some general complications that can occur with any surgery. These include:
- Blood clots
- Nausea and vomiting
- Side effects of anaesthesia
- Post-operative pain
Your surgeon will make every effort to ensure that none of these problems occur. It is also key that you follow your surgeon's specific guidance before and after surgery. This helps to further reduce the likelihood of gastric bypass risks and complications. If you have any questions about the risks, you surgeon will be happy to answer them for you.
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All of the information found on our website is sourced from highly reputable experts, government-approved authorities and is widely used by healthcare professionals.
- https://www.nhs.uk/conditions/weight-loss-surgery/ NHS
- Uptodate.com Up to Date
- https://asmbs.org/patients/bariatric-surgery-procedures American Society of Metabolic and Gastric surgery
Our content is written by our Medical Quality Managers and Patient Care Advisers, all of who have medical backgrounds and training. Prior to publishing, all the information is reviewed by a surgeon specialised within the relevant field.