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Preparing for metabolic and bariatric surgery

We strongly recommend starting the steps outlined on this page in advance of orientation. Ensure you have a good understanding and reasonable expectations of bariatric surgery, then introduce lifestyle changes to food intake and exercise. 

Remember, bariatric surgery is just a tool. You still need to make significant lifestyle changes in order to be successful in your efforts to lose weight and keep it off. Our team will help you work towards sustainable changes prior to surgery and will follow you for up to 2 years after surgery to address any nutritional deficiencies and support you through your journey.


Begin by researching bariatric surgery to prepare yourself for what to expect both before and after this life-altering surgery. 

At Richmond Metabolic and Bariatric Surgery (RMBS),  all our surgeries are done using laparoscopic techniques, also known as minimally invasive surgery. We offer four types: VSG, RNY, BPD-DS and SADI-S. We do not offer lap bands or other types of surgeries. 

Review the description of each type of surgery below before you meet the surgeons. Your surgeon will help you decide which surgery would be best for you by discussing the types of surgeries, their benefits and their risks.

You can also read patient testimonials on the Obesity Help website.

Laparoscopic vertical sleeve gastrectomy (VSG)

The Vertical Sleeve Gastrectomy is performed by making several small incisions in your abdomen. A vertical incision is then made to remove approximately 80-85% of your stomach. Your new stomach sleeve, which is shaped similar to a tube, holds approximately 100 -125ml in the beginning. This new smaller stomach significantly reduces the amount of food and calories that can be consumed. It also causes favourable changes in gut hormones which help to suppress your appetite, improve the feeling of satiety (or fullness) soon after eating, and improve blood sugars. 

Laparoscopic roux-en-y gastric bypass (RNY)

Your laparoscopic surgery will involve 6 small incisions in your abdomen. A small pouch about the size of a large egg is made at the top of your stomach and then your small intestine is divided just past your stomach. One end of the intestine is attached to your new stomach pouch and the remainder of your stomach is bypassed (food no longer travels through this remnant stomach) though remains in your body. The other end of your divided intestine (the one attached to your remnant stomach) is reattached to your small intestine a little further down. This allows for digestive juices and enzymes to meet with the food stream. This procedure not only reduces the size of your stomach but also reduces how much food you absorb by bypassing part of the small intestine. This is considered to be the Gold Standard for bariatric surgery as there is significant weight loss along with significant improvements in obesity-related illnesses such as diabetes, high blood pressure, heart disease, GERD, etc.

Laparoscopic single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S)

This procedure is a modified version of the Duodenal Switch (described in detail in the next section). The duodenum is detached just below the stomach and reattached to a loop of the small intestine about 3.6 meters downstream. This creates two separate pathways and one common channel. The shorter pathway (digestive channel) allows food to flow from the stomach to the common channel. The longer pathway (biliopancreatic channel) carries bile from the liver to the common channel. This diversion limits the amount of time that food mixes with digestive juices and reduces the number of calories that can be absorbed, leading to weight loss. 

Biliopancreatic Diversion with Duodenal Switch (BPD-DS)

Biliopancreatic diversion with duodenal switch (BPD/DS) or simply duodenal switch (DS) is a bariatric surgery that can help patients lose up to 80% of their excess body weight. It is performed laparoscopically and often done as a single-stage surgery but can also be done for patients that have had a VSG in the past and still have significant weight to lose or struggling with comorbidities such as, DM2, HTN, dyslipidemia, etc. It can help you lose more weight and improve your comorbidities by its malabsorptive action via reducing the absorption of macro and micronutrients (vitamins and minerals).

In this surgery, the intestine is bypassed starting from below the pylorus to the ileum, 50 to 125 centimetres from the colon. The bypassed portion of the intestine (biliopancreatic limb) delivers bile and pancreatic juices to the anastomosis at the ileum, where it meets the alimentary limb (proximal duodenum, through which food passes) to form the common channel. This is where food combines with bile and pancreatic juices for the first time and most nutrient absorption occurs.

Weight loss

Learn how to eat and exercise in a way that will ensure your long-term weight loss goals. Patients who demonstrate significant lifestyle modification during the pre-conditioning phase will be considered for surgery.

Weight gain through the pre-operative stage may be associated with poor outcomes and surgical risks. Therefore, we encourage our patients to gradually lose weight prior to the surgery. We understand this is difficult for many patients, and weight stability may be a more feasible goal. This will be reviewed on an individual basis.

This diary is crucial to success! It allows patients and the members of the team to track progress and find areas where positive changes can be made.

  • This can be in the form of a booklet, recorded on the computer or on a mobile phone app - many of our patients have found the MyFitnessPal and Baritastic app to be very useful

  • Write down daily food and beverage intake including types of foods, beverages and condiments. Record the quantities of each (e.g. grams, tablespoons, ounces, etc.). Don't forget to record snacks too as these types of foods are often an overlooked source of calories.

  • Write down daily exercise activities including the type of exercise and duration

  • Record your weight once a week (first thing in the morning, on the same day and using the same scale).

  • Bring the diary to each and every appointment with our team. Motivation and commitment are keys to being considered for bariatric surgery. Forgetting your diary shows a lack of both.

Make slow, progressive changes to your food intake. Remember the goal is balanced, healthy meals for durable, long-term change. The Dietitians will meet with you regularly to review your diary and provide expert guidance on how to shop for food, cook food, food prep, and read labels. Learn more about nutrition before surgery in our Richmond metabolic & bariatric surgery manual.


The nutrition videos below do not replace the individual advice you've been provided at your dietitian appointments or from your physician(s). They are simply to provide you with general information for learning purposes.

Dietary tips

  • Gradually limit meals eaten at restaurants and fast-food outlets. You have much better control of the food you eat when you buy it and cook it yourself. Don't shop for groceries on an empty stomach – this helps to avoid impulsive decisions.

  • Focus on fresh foods in the grocery store. These are a much better alternative to processed foods. Fresh foods are most often located along the outer aisles of a grocery store, while processed foods are located in the centre. If it comes frozen in a package and needs the microwave to cook it, it's often not the best choice.

  • Get into the habit of reading labels. The more knowledge you have about foods you are eating, the more control you have over making healthier choices.

  • Eat breakfast, lunch and dinner at similar times every day. Remember – breakfast really is an important meal that should not be missed. Aim to have 3 small meals and 2 snacks per day.

  • Plan your meals the night before - again, it is very difficult to make good food choices when you're hungry! Planning ahead helps to prevent impulsive food choices.

  • Separate solid foods from liquids by 30 minutes and vice-versa.

  • Liquids should be limited to water, tea, skim milk and diluted, light cranberry juice.

  • Drink 6-8 glasses of water a day.

  • Food and drinks to avoid – It is obvious that some foods such as fried food and fast food are high in calories. Here are some items that you might not know are also high in calories that - jams, pop (diet pop is ok), juice, alcohol, condiments (including ketchup).

As with dietary changes, the goal is to gradually introduce exercise in a safe way in order to slowly condition your body and avoid injury. We encourage our patients to slowly work towards 30 minutes of sustained exercise daily as tolerated. HealthLink BC offers free resources for evidence-based physical activity information and professional guidance relating to exercise and physical activity for patients that need help getting active. To access the Physical Activity Services, call 8-1-1 and ask to speak with a Bariatric QEP (Qualified Exercise Professional).

Learn more about nutrition before surgery in our Richmond metabolic & bariatric surgery manual.

Exercise tips

  • Focus on cardiovascular exercise – not weights.

  • Dedicated time should be set aside for exercise. Cleaning the house or walking around at work doesn't count!

  • Start with walking, swimming or walking in the pool. Begin with 10-15 minutes at a time and gradually work your way up to 30-40 minutes a day, 6 times a week.

  • Don't forget to record this in your diary.

Mental health

Even though bariatric surgery has a positive effect on many people's mental health in the long term, unaddressed trauma or mental health-related issues can increase vulnerability during the recovery period. While dysphoria or anxiety that is related to obesity can gradually be improved with weight loss, there are some patients who are unable to cope with the stresses of post-operative life and are at increased risk of self-harm. We require everyone to address mental health issues and be stable for at least 18 months (as confirmed by a family physician), and to have adequate support in place for purposes of risk reduction.

Sleep apnea

Sleep apnea is a serious breathing disorder that is often found in obese patients. Everyone who enters the bariatric program will be evaluated and undergo a home sleep apnea test and if results are abnormal, a polysomnogram (sleep study) may be ordered in the Richmond sleep lab, to provide a more comprehensive diagnostic assessment. A referral to our team respirologist may be required.

If you are diagnosed with sleep apnea, you will be fitted with an apparatus called a CPAP machine. It must be used every night. Diligent use of the CPAP machine improves the quality of restful sleep. More importantly, it helps to decrease the chance of cardiac and respiratory complications after surgery. Failure to use the machine may result in delay or cancellation of surgery.

SOURCE: Preparing for metabolic and bariatric surgery ( )
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