Bariatric (obesity) surgery
Surgical treatment of obesity
On this page:
- Type of surgery
- Patient evaluation and selection
- Eligibility for surgery
- Weight loss
- Recuperation and follow-up
- Eating methods after surgery
The surgery for obesity performed at UC Davis is a separated gastric pouch with creation of a Roux-en-Y bypass. This means that the stomach is made into a small pouch which holds approximately two tablespoonfuls of food. The small intestine is then divided and sewn to the pouch so that food goes from the stomach pouch directly into the small intestine.
Recently, surgeons at UC Davis Medical Center have been performing this surgery laparoscopically on selected patients. The eligibility for this procedure is determined by calculating the patient's body mass index (BMI) at the time of the initial consultation. The laparoscopic method involves making five one-half inch incisions and performing the operation by observation through a small camera.
Inpatients who are not eligible for the laparoscopic method, surgery is done with an "open" incision extending from just below the breastbone to just below the navel. The recovery time for the laparoscopic procedure is expected to be several weeks shorter because of the smaller incisions, though similar possible complications exist.
The program begins with at least two pre-operative interviews with each patient in order to review their medical and surgical history, psychosocial history and the patient's understanding of the method of operation, possible complications, and post operative diet and exercise requirements. Candidates for surgery are chosen based on clear information that the medical indications for gastric bypass are met as well as the patient’s candidacy for major surgery as determined by our team. A medical evaluation by the patient’s primary-care provider, including laboratory work, should accompany the patient to their visit with our team. Psychological assessment is required as well and is to be done by a therapist who will be available for the patient post-operatively, if needed. This assessment should be provided by the patient on the initial visit.
Once a patient is selected for surgery, insurance authorization is requested and must be received prior to scheduling surgery. During this time period medical clearances (studies to assess the status of the heart or other organs), when necessary, are to be obtained by the patient in order to fulfill requirements of the surgeon and anesthesiologist. These studies are done to assure the safest operative and post-operative course possible.
In general, patients seeking gastric bypass for weight loss must be at least 100 pounds overweight and have failed prior medically supervised attempts at weight loss. Documentation of such attempts will need to be provided at the time of consultation; if unavailable, we may recommend a medically supervised weight-reduction program prior to further consideration.
The method of weight loss is the restriction of oral intake because the stomach becomes full with small amounts of food. Over time, the pouch stretches so that, in order to successfully lose weight and maintain a lower weight, the patient must adhere to a lifelong low-fat, low-calorie diet. The rate of success with this surgery varies; approximately 30% to 40% of the patients lose at least 100 pounds of their excess weight and are able to maintain this loss for years. Approximately 50% to 60% lose 100 or more pounds and then regain some of the weight. Approximately 10% to 20 % lose less than a desired amount of weight or regain a good deal of their weight. The successful patient is one who is able to maintain a low-fat, low-calorie diet and maintain some degree of regular exercise. Our dietitian is available for all post-operative patients to assist with dietary selection.
Following the surgery, patients are in the hospital for a minimum of 2 to 10 days if there are no major complications. Patients undergoing the laparoscopic method usually have a shorter hospitalization. Some patients remain on the ventilator for one to several days, depending on their ability to breathe without assistance. The status of the patient’s lungs prior to surgery is important to know, as those with prior lung disease are more likely to require mechanical ventilation for longer periods.
Your activity will be restricted to no strenuous activity for three to six weeks after the operation. You may walk, perform light household duties as tolerated upon your return home. Most patients remain off work from three to six weeks. Patients undergoing the laparoscopic procedure are more frequently able to return to all activities within the shorter time frame.
Post operatively, each patient is seen weekly and then every two to three weeks for one to two months, provided there are no complications. After the first two months, patients are seen on a monthly to quarterly basis for one year and then semi-annually and annually as deemed necessary. Patients are seen by the dietitian, surgeon and/or nurse practitioner at each visit.
What to expect after gastric bypass surgery:
After a gastric bypass you will need to make changes to your eating patterns. The patient's diet after surgery progresses from a liquid diet, to a pureed diet, to a soft diet and then to a modified regular diet. The diet progression is designed to allow you to heal. Initially, it helps you meet your protein and liquid needs, and later to meet your nutrition needs. It is important that you follow the diet progression to maximize healing and minimize risk for complications. The size of your stomach after surgery is about one ounce or one-two tablespoons. By six months after surgery, it may stretch to eight ounces or one cup. Long term, the size of your stomach is likely to be 8-12 ounces. This will limit the amount of food you can eat at one time.
The first eight weeks after surgery: In the first eight weeks after surgery, you need to change your eating habits to avoid pain and vomiting and to aid in weight loss. You want to prevent obstruction of the area where your stomach pouch connects to your intestine (the stoma).
Lifetime success: To maintain a healthy weight and to prevent weight gain, you must develop and keep healthy eating habits. You will need to be aware of the volume of food you can tolerate at one time and make healthy food choices to ensure maximum nutrition in minimum volume. As well, exercise must be a part of your daily routine.
Long-term eating goals:
Swallowing food in chunks may block the stoma and prevent foods from passing into the intestine. It is CRITICAL that you eat slowly and chew food well to lower the risk for getting anything caught in this area. The following tips may help you eat more slowly.
set aside 30-45 minutes to eat each meal
aim to chew your food 30 times with each bite, ground or soft foods may be necessary if you have dentures
explain to friends and family why you must eat slowly so they will not urge you to eat faster
take small bites of food (you may want to use a smaller spoon and use a saucer in place of a plate to help you with portion control)
pay attention to taste; learn to savor your food
stop eating as soon as you are full (over-eating even one oz. can make you vomit and can lead to stretching your pouch)
Feelings of Fullness
Learn to recognize when you are full. Indications of fullness may be:
A pressure or fullness in the center of your abdomen just below your rib cage.
Feelings of nausea, regurgitation or heartburn.
Vomiting may occur after gastric bypass surgery. It is often the result of eating inappropriately but can be caused by a surgical complication and should be reported to your surgeon.
Eating inappropriately is the most common cause of vomiting. Common eating related causes of vomiting are:
eating too fast
not chewing food properly
eating too much food at once
eating solid foods too soon after surgery
drinking liquids either with meals or right after meals
lying down after a meal
eating foods that do not agree with you
If you begin vomiting that continues throughout the day, stop eating solid foods and sip clear liquids (clear, diluted juice, broth, tea). The vomiting may indicate that the stomach pouch is blocked. If vomiting continues for more than 24 hours, contact your doctor.
Meal Pattern/Balanced Diet
It is important to eat foods with good nutritional value. The quantity of food you are able to eat at a meal will be reduced. Eating three meals per day will be essential. Meals should be made up of solid foods. Liquids should be consumed between meals. Each meal should have at least two ounces of a protein source (such as eggs, cottage cheese, fish, poultry, beans, meat, tofu). Limit fat intake. You must learn to read labels, choose lower-fat foods and choose lean-protein foods.
Avoid snacking. Snacking can add significant calories and keep you from losing weight. Inappropriate snacking can even lead to weight gain. The volume you can tolerate will always be limited so choose foods wisely to avoid filling up on foods with little nutritional value. Eating foods from each of the five food groups will provide balance. You must get a maximum amount of nutrition in a minimum amount of food.
Drink at least six cups of liquids per day, between meals. Recommended beverages are skim milk, water, low or no-calorie drinks. Tea or coffee can be re-introduced in small quantities eight weeks after surgery.
Do not drink beverages 30 minutes before or after meals. (There is not enough room in your stomach for both food and liquids.)
Sip beverages slowly.
Avoid drinking from a drinking fountain or from a straw (it is more difficult to control the volume of your intake).
Eliminate high calorie drinks such as milkshakes, regular soda, beer and other alcoholic beverages. The calories from these drinks can add up quickly if you are sipping on them throughout the day.
Vitamins and minerals
A chewable or liquid multivitamin and mineral supplement is required daily until 12 weeks after surgery. After this, it is recommended that you take a regular multivitamin and mineral supplement daily for the rest of your life. You may also need to take a B12 supplement (ask your doctor or dietitian about your need for this). You must have your B12, iron and folate levels checked annually by your doctor to be sure your supplements are adequate.
Certain foods may be difficult to tolerate
Tolerance to foods varies from one individual to the next. Once you are back on a more regular diet, through trial and error you may find you are able to tolerate some foods better than others. There may be some foods that your digestive system cannot handle well.
Many things can cause discomfort and vomiting. Sometimes the source may be a specific food. Do not avoid a food just because you vomit once after eating it. You may wish to wait a few days, but you should try that food again. Tolerance to foods may improve with time. ALWAYS be sure to chew foods very well, take small bites and eat slowly.
Detailed information about the post-gastric bypass diet will be provided in clinic.