Bariatric Surgery Service

Obesity is caused by consuming more calories than the body uses over a sustained period of time; this excess is stored in the body as fat. It is a chronic condition that can be difficult to treat. 
   
There are many causes of obesity including metabolic, environmental, genetic, hormonal and a disordered relationship with food. Those who suffer with obesity are also more likely to develop a range of other diseases including diabetes, coronary heart disease, high blood pressure, sleep apnoea and early arthritis; which can only be managed by losing weight.

Bariatric surgery is a term used to describe a number of different operations which make the stomach smaller and in some cases, change the anatomy of the small intestine to alter how the body digests and absorbs food.

There are two ways that surgery can help weight loss:

• by decreasing food intake  : surgeries include gastric bypass and sleeve gastrectomy. These limit the amount of food that can be held by the stomach by making the stomach smaller
• by causing food to be poorly digested and absorbed  : such as the duodenal switch. This connects the stomach to a lower section of the small intestine, which means that the amount of calories absorbed into the body is decreased.

If you live with obesity and have been unsuccessful with other weight loss methods or you have an obesity-related disease, then surgery may be an option for you.

You may be eligible for surgery if you:

• have a BMI (body mass index*) of 35 or more with an obesity-related physical problem such as diabetes, high blood pressure, sleep apnoea or early arthritis that could be improved with weight loss
• have a commitment to life-long follow up.

It is important that you consider all the options, and know the risks and benefits, before deciding to proceed with obesity surgery. At Homerton, you will have access to a range of professionals who will be able to discuss the other aspects of your healthcare such as nutrition, aftercare and physical activity.

This operation reduces the stomach capacity by about 75%. The stomach is divided vertically from top to bottom and the divided part is removed completely. This operation makes the stomach smaller, meaning you will eat much smaller meals but remain fuller for longer. The operation does not affect the intestines at all, so digestion remains largely unaffected. 

You will need to follow the after-surgery guidance to ensure you maintain a balanced diet with adequate protein and micronutrients (vitamins and minerals). This will reduce the risk of any problems occurring and support you to achieve the best weight loss outcomes possible. You will also need to take vitamin and mineral supplementation lifelong and have routine (at least annual) blood test monitoring to prevent nutritional deficiencies.

On average people lose 20-30% of their total body weight after surgery.

Assuming that everything goes well, you will be discharged from hospital one to two nights after your surgery. It generally takes patients two to six weeks to recover and resume normal activities.

Sleeve gastrectomy can be used as the first stage of a gastric bypass operation or a stand-alone procedure.

Bypass operations can be lengthy and complex procedures; for some (those with a higher BMI) it may not be suitable for them to undergo a full bypass straight away. If this is the case then a sleeve gastrectomy is recommended as the first part of a two-stage operation, the second stage being a conversion to a roux-en-Y gastric bypass.

Patients will sometimes lose enough weight with a sleeve gastrectomy that they do not need to undergo a second stage operation. If a second operation (bypass) is required this will usually be done between six and twelve months after the first operation, depending on the amount of weight loss achieved.

All obesity surgery is associated with certain side effects. For sleeve gastrectomy this can include: leaking from the newly formed stomach or vomiting due to over-eating. Sleeve gastrectomy also increases the risk of acid reflux. However, your condition will be monitored through lifelong check-ups that you will have with our specialists, to ensure that we act quickly if there are any problems.

It is also important that you follow our after-surgery guidance to reduce the risk of any problems occurring.

For further info. visit https://www.ifso.com/patient-sleeve-gastrectomy/

The Roux-en-Y gastric bypass is the most common gastric bypass procedure. A small pouch is created at the top of the stomach by using staples. Then the small intestine (which carries food from the stomach) is cut and attached to the pouch. This closes the rest of the stomach.

Gastric bypass works by several mechanisms. Most importantly, the rerouting of the food stream alters gut signals leading to increased satiety, reduced hunger, changes in taste and improved blood sugar. In addition, the newly created stomach pouch is considerably smaller and facilitates significantly smaller meals, which translates into less calories consumed.

On average, people lose 20-30% of their total body weight.

You will need to follow the after-surgery guidance to ensure you maintain a balanced diet with adequate protein and micronutrients (vitamins and minerals). This will reduce the risk of any problems occurring and support you to achieve the best weight loss outcomes possible. You will also need to take vitamin and mineral supplementation lifelong and have routine (at least annual) blood test monitoring to prevent nutritional deficiencies.

Assuming that everything goes well, you will be discharged from hospital one or two nights after your surgery. It generally takes patients between two to six weeks to recover and resume normal activities.

All obesity surgery is associated with certain side effects. For gastric bypass procedures this can include: dumping syndrome, internal hernias, vomiting or bleeding or leaking from the join between the stomach and intestine. Surgery is performed laparoscopically to reduce the risks of complications.  Smoking significantly increases risks associated with this operation.

Further information and advice about these operations will be made available to you at your consultations with our specialists.

For more information visit https://www.ifso.com/gastric-roux/

One-anastomosis (Mini) gastric bypass is a relatively new operation first performed in 1997. This involves stapling the stomach starting from its lower part (known as the antrum) to create a long gastric pouch. The rest of the stomach remains in but food does not go into this (hence the name bypass).

The small intestine is then connected to the bottom of this pouch in such a way that the first part is bypassed.

Few research studies have examined the changes after this operation but it is thought to work mainly through altering gut signals which control appetite, taste and blood sugar but also through restricting the size of the stomach.

The re-plumbing means that bile contents can pass into the stomach and food pipe resulting in bile reflux. 

On average people lose 25-30% of their total body weight.

One-anastomosis (Mini) gastric bypass requires adherence to dietary recommendations, life-long vitamin/mineral supplementation, and follow-up compliance. 

For further information see: https://www.ifso.com/one-anastomosis-gastric-bypass.php

Image source: https://www.ifso.com/one-anastomosis-gastric-bypass.php

Excess skin is a common result of significant weight loss following bariatric surgery. Since the skin stretches over time, it may lose its natural elasticity and struggle to fully tighten afterward. Several factors influence this, including age, speed of weight loss, and smoking history. Younger people tend to have more elastic skin, whereas rapid weight loss leaves less time for the skin to adjust. Smoking also impairs skin’s ability to heal and stay firm.

While diet and exercise can improve skin tone, they won’t eliminate loose skin entirely. You may be left with excess folds and rolls of skin, particularly around your breasts, tummy, hips, and limbs.

To help your skin look and feel better, it's recommended to:

• build muscle through regular strength training
• eat protein-rich foods like meat, chicken, fish, eggs, tofu, beans, pulses, and dairy
• stay hydrated to support skin elasticity
• follow a skin care routine: gently exfoliate and moisturise regularly to improve texture and hydration.

These steps can improve your skin’s condition but may not remove excess folds. In some cases, people explore surgical options like body contouring for long-term solutions.

Removing excess skin with plastic surgery is not part of the original operation. It may not be available on the NHS and usually needs approval through your GP. Some people may need to pay for it privately. You can speak with your GP if excess skin is a concern.

Weight Loss Expectations

Bariatric surgery can be a highly effective weight loss tool. Most weight loss occurs in the first 12 months and weight loss usually stops by 18-24 months. 

Weight loss after surgery is highly variable between individuals. However, average weight loss from a bariatric surgery procedure is 20-30% of total body weight. This often leads to clinically significant health benefits. It is important to be aware that achieving a ‘healthy’ BMI is not a realistic goal for most people who undergo bariatric surgery.

What does 30% weight loss look like at different starting weights?

table

Weight at surgery	127kg	190kg
Weight after surgery	90kg	133kg
Weight lost	127kg - 90kg = 37kg	190kg – 133kg = 57kg
% Weight lost	37kg / 127kg * 100 = 29%	57kg/190kg * 100 = 30%

After weight loss stabilises, it is common to experience a small degree of weight regain. It is important to continue to follow the dietary and lifestyle guidelines lifelong to maintain your weight loss. 

If you experience ongoing weight regain, it can be helpful to access additional support from services such as: 

• local community dietitians
• community weight management programmes
• specialist tier 3 weight management services
• exercise on referral.

Every patient seeking to access bariatric surgery is an individual and may face particular challenges in different domains. This could include physical health, pain, medical complications and emotional wellbeing.

For this reason, our pathways are dynamic and varied, which make it difficult to predict how long it may be to get to surgery. Typically, the pre-operative journey between assessment and surgery is 18-24 months but this will depend on individual needs and in some cases can be longer.

We understand that this can be frustrating, and we aim to communicate the next steps in your journey to you at either your appointment or in writing following internal meetings (MDTs) where results of investigations or assessments may be discussed.

Whilst bariatric surgery is the most effective treatment for managing excess weight, undergoing this procedure may not be right for everyone. Our team may at times feel that the surgical risks outweigh the potential benefits or that the risk of a negative long-term outcome is too high. At these times patients will be asked to undergo treatment outside of the bariatric service and be discharged.

Whilst we understand that this can be disappointing, as a service we are committed to safeguarding our patients as well as our staff to enable them to continue providing good care. Abuse of staff will not be tolerated, and patients may be discharged from the service following an incident review.