Currently, the body mass index (or BMI) is considered the best available indicator of excess body weight. BMI is calculated by dividing an individual’s weight in kilograms by the square of the height in meters. Your weight in pounds can be converted to kilograms by dividing it by 2.2; your height in inches can be converted to meters by multiplying it by 0.0254.
Someone who is 20 percent or more over their ideal body weight typically has a BMI of 30 kg/m2 or higher. Clinically severe (or morbid) obesity is considered to be 100 pounds or more over ideal body weight, corresponding to a BMI of 40 kg/m2. People with a BMI greater than 35 kg/m2 and serious health problems related to obesity are also categorized as having clinically severe obesity.
BMI is used to predict which patients are at the highest risk for weight-related medical problems and identify which patients would benefit most from procedures designed to help them lose weight. People with clinically severe obesity are at a much greater risk of serious health problems and death than those of the same age at ideal body weight. Some examples of the medical problems that occur more frequently in people with BMIs over 35-40 kg/m2 are:
• Hypertension (high blood pressure),
• Coronary artery disease (including heart attacks),
• High cholesterol,
• Sleep apnea,
• Degenerative joint disease,
• Blood clots in the veins of the legs and lungs,
• Incontinence, and
• Pseudotumor cerebri (increased pressure within the skull, resulting in headaches, vomiting, blurred vision and other effects).
Other problems related to obesity can include depression, low self-esteem, physical disability, social discrimination, and unemployment -- to name only a few.
In 1991, the National Institutes of Health examined this issue extensively. Their findings are what we use to identify patients that are most likely to benefit from bariatric (obesity related) surgery: to be a candidate for such surgery, a person must have a BMI over 40 (or a BMI over 35 with serious co-morbidities). There are other factors we consider when attempting to identify the best candidates for surgery, but these are the most basic criteria. Other factors we consider are willingness to adhere to a lifelong modification in daily diet and exercise, psychological stability, and if an effective social support system exists. Candidates for surgical treatment must also have previously attempted to lose weight by dietary and lifestyle modifications.
There are a number of operations devised to help people lose weight and keep it off. They are restrictive, malabsorptive, or a combination of the two. Restrictive procedures limit the amount of food the stomach can hold. Malabsorptive procedures limit the number of calories and nutrients that can be absorbed.
Three procedures are offered at UTMB’s Center for Obesity and Metabolic Surgery. They are Roux-en-y Gastric Bypass, Adjustable Gastric Banding and the Gastric Sleeve procedure.
The Roux-en-y Gastric Bypass procedure is a restrictive and malabsorptive procedure. Evidence indicates that this is a safer and more effective method for sustained weight loss than many other surgical options. Gastric bypass involves partitioning the stomach so that swallowed food quickly fills a very small stomach “pouch”. This pouch is designed to initially hold less than an ounce. A segment of the small intestine (called the jejunum) is then connected to this small pouch through a very small opening (called an anastomosis) in an arrangement that surgeons have termed “Roux-en-y”. These surgical changes physically restrict food intake and limit the sensation of hunger. Food fills the small pouch quickly and stretches the walls. Stretch receptors in the walls send a signal to the brain to turn off the hunger sensation. The very small opening between the stomach pouch and the small intestine limits how fast the pouch can empty. Thus, you feel full after ingesting only a small amount of food or liquid and stay full longer. Finally, the connection of the jejunum to the pouch can prevent the digestion of certain high-caloric (carbohydrate) foods.
Obviously, the answer to this question depends upon a variety of circumstances. In terms of weight loss, most people (around 90 percent), will lose between 50–80 percent of their excess body weight. For someone weighing 350 pounds, with an ideal body weight of 150 pounds, this is equal to a loss of 100–160 pounds. Most of the weight loss occurs in the first six months; people usually reach a stable weight within 18–24 months. There are specific things each patient can do to increase his or her chances of success. We closely follow each patient in order to teach these techniques and optimize each patient’s result. Some people lose more than the average 50–80 percent. Often the greatest benefit of gastric bypass surgery is in reducing the impact of coexisting diseases, and sometimes curing them altogether. For example, 80–90 percent of type II diabetics no longer need medication (within days to months) after this operation. Acid reflux is usually cured. Cholesterol levels come down to the normal range. Dependence on blood pressure medication often vanishes. As weight is lost, there is less force on damaged joints, causing much less pain and better mobility. Women with fertility problems may return to a normal ovulation cycle and become pregnant. And, minimized obstruction in the airways often cures sleep apnea.
No, this operation should be considered irreversible.
A leak is the breakdown of an anastomosis (a place where organs are joined together by staples or stitches) which happens in about 1–2 percent of patients. A leak can make someone very sick and is usually discovered within the first few days after surgery. Repair of the leak most often requires another operation to drain the spillage of gastrointestinal contents. This operation is usually best performed through an incision from the end of the breastbone to the navel. A leak can prolong hospitalization by several weeks. Sometimes leaks do not occur until several days (or longer) after the operation.
This is a very uncomfortable feeling that some people experience shortly after eating. Foods high in carbohydrate content (candy bars, cakes, ice cream) cause fluid shifts when emptied directly into the jejunum. Symptoms can include heart palpitations, sweating, light-headedness, nausea, bloating, cramps and a feeling that something “bad” is going to happen. The duration is variable, but these feelings go away without any specific treatment other than lying down to rest. The symptoms are usually completely avoidable by sticking to diets low in carbohydrates. Avoiding these foods also allows for greater weight loss.
There definitely are ways to regain weight after this operation. Some refer to this as “beating the pouch.” We encourage people to think of this operation as providing a tool for their use. If used incorrectly or not at all, the weight will return. In other words, the pouch can be “beaten.” While we cannot predict who will regain weight, we can usually ascertain the reason once the regain is identified. The small pouch created during the operation will gradually enlarge over time. (There are some habits that can cause this to happen sooner than necessary, and to a greater degree than expected, but most of these are prevented with the dietary instructions you will receive.) Nevertheless, as it enlarges, it becomes able to hold more food. As the opening into the jejunum enlarges, the pouch empties faster. Faster emptying, plus a larger pouch, equals the sensation of hunger returning. We expect that during the first two years of the pouch’s use, a patient undergoes a fundamental change in his/her approach to eating. Once these healthy eating habits are learned, most people use them for life and can control their weight forever, even if increased hunger occurs. Even in patients that regain weight, a return to healthy eating habits and effective use of the pouch as a weight loss tool allow them to reclaim control.
The adjustable gastric band procedure (see illustration below) is a restrictive procedure. It reduces the stomach capacity and restricts the amount of food that can be consumed at one time with a band that is placed at the top of the stomach and tightened to create a small pouch. A small tube connects the band to a port placed under the skin of the abdomen. Adjustments can be made by injecting saline solution into the band through the port. These adjustments can increase or decrease the size of the stoma or stomach outlet.
Obviously, the answer to this question depends upon a variety of circumstances. In terms of weight loss, most people will lose between 50-60 percent of their excess body weight. For someone weighing 350 pounds, with an ideal body weight of 150 pounds, this is equal to a loss of 100-120 pounds. Weight loss is generally slower with the adjustable gastric band procedure as compared to the Roux-en-y Gastric Bypass Procedure.
Yes, the band can be removed at any time through a similar procedure. The stomach and other anatomy are intact.
Your primary care physician may refer you to our program. You may request a patient information packet from our offices or download one off our web site. This packet provides us with information about you, your medical history, and your insurance providers. Once we receive this basic information from you, we will begin your evaluation.
Yes. Although the Roux-en-y Gastric Bypass has historically been performed through a long incision in the midline of the upper abdomen, most patients meeting the requirements for gastric bypass can have the procedure performed laparoscopically. Laparoscopic surgery is a “minimally invasive” approach in which the operation is performed using long instruments and staplers placed through several small incisions at strategic locations on the abdominal wall. A long telescope attached to a video camera is used to view the procedure.
The advantage of laparoscopic surgery is that although the operation on the inside of the abdomen is the same as if the procedure were done with the open technique, the injury to the abdominal wall is kept to a minimum. With small incisions, there is often less pain, a quicker recovery and a lower risk of hernia formation. For these reasons, the laparoscopic technique is the procedure preferred by most patients as well as the surgeons at our facility. However, some people are not candidates for a laparoscopic approach. If you are not a candidate for the laparoscopic procedure, you may still qualify for gastric bypass. Your surgeon will discuss these issues with you when you visit our clinic.
Adjustable gastric band is done through laproscopic technique. Tiny incisions are made in the abdomen through which long thin instruments are inserted to place the adjustable gastric band on the stomach. A long telescope attached to a video camera is used to view the procedure.
Although the incisions may be very small, this is a still a major surgical procedure. All operations have some risk of complications. Some are as minor as a small wound infection; some are as major as death. We offer this procedure to people whose risk of remaining morbidly obese is higher than the risks associated with the operation. With thorough preoperative testing, careful surgical technique, and close postoperative care and follow-up, we make every effort to avoid complications.
However, the risk of complications always exists. We have listed some of the risks of remaining obese in a preceding section of this guide. In order to make an informed decision about having this operation, each candidate must be aware of the possible complications of surgery. A list of the most commonly occurring complications are provided below. It is by no means exhaustive. Possible complications are grouped by the expected time of occurrence, but some may happen at unexpected times.
Yes, once a patient’s weight is stabilized, pregnancy is possible. However, becoming pregnant during a period of rapid weight loss can result in severe nutritional deficiencies in the fetus, miscarriage, and/or fetal developmental problems. Women of childbearing age should ask their gynecologist to prescribe oral contraceptive medication for at least the first 18 months after this operation. The decision to become pregnant should be fully discussed with the doctors at the Center for Weight Management and with a qualified obstetrician.
One benefit of the adjustable gastric band procedure over the Roux-en-y Gastric Bypass is the adjustable gastric band can be adjusted to increase the stomach outlet size to accommodate increased nutritional needs during pregnancy.
Blood clots in the legs can break off and be trapped in the lungs. This pulmonary embolism, as it is called, is the most frequent cause of death after bariatric surgery. Exercising the legs helps pump blood out of the legs, preventing it from pooling there and clotting. The patient has control of the most effective preventive measure. We will administer a medication called heparin, and provide lower extremity compressive devices, but getting up and moving as soon as is medically possible (as advised by your physician) is the best means of prevention.
Studies have shown that in people who have not had their gallbladders removed there is about a 30 percent chance of developing gallstones during the period of rapid weight loss. Most of these patients do not get symptoms from the stones. A medication can be taken for six months after surgery that decreases the chances of getting gallstones to about 2–5 percent.
Due to the locations where nutrients are absorbed in the gastrointestinal tract, nutritional deficiencies do occur. However, nutritional deficiencies are very uncommon in patients who take their supplements and return to the clinic according to the follow-up schedule. During these follow-ups, blood tests will screen for deficiencies and supplements will be added as necessary. The main problems we see are deficiencies of protein, vitamin B12, iron, and calcium. The symptoms of these deficiencies can be very subtle, so follow-up visits to our clinic are crucial. In addition to a healthy diet, all patients should take calcium and two chewable multivitamins containing iron everyday. B12 and protein supplements will be added if needed.
Those who exercise daily will enjoy the best results.
You should start exercising as soon your physician allows it after the surgery, and ideally beforehand (right now, if possible). Even if you are unable to walk, there are aerobic exercises that can be done in a swimming pool, chair or bed. However, some people have medical reasons that may rule out vigorous exercise, so they should follow their doctor’s advice.
Absolutely, you can think of this operation as providing you with an effective weight loss tool. Nearly everyone loses weight during the first six months, but if you use the tool correctly, you will keep the weight off. If you don’t, you won’t. Most people simply have no appetite and no desire to eat during the first 6–12months. Eventually hunger will come back. By then, you will have learned about the proper diet to follow. Using the tool means sticking to that diet. The tool will be available for your use forever.
About two hours (no kidding). You will be helped out of bed very soon after the operation. Two of the most serious complications related to this operation can be almost completely avoided by getting out of bed and moving around as soon as possible. An upright position allows the lungs to expand fully preventing atelectasis, or collapse of the small air spaces deep inside the lungs. These collapsed air spaces can cause fevers and lead to pneumonia. This movement also helps prevent deep venous thrombosis and pulmonary embolism (blood clots in the legs and lungs). After that first adventure out of bed following surgery, walking will become easier. Your activity will gradually increase so that you will walk out of the hospital to go home (usually two or three days after surgery). Once home, activity should be increased at a pace that depends upon your level of discomfort.
That depends upon several factors. Usually we can evaluate and determine medical eligibility within a few weeks or months of receiving your information packet. Most often, the step that slows the process is fulfilling the requirements of an insurance company. Some companies require several months of exercise and diet, supervised and documented by a physician. Some require certain preoperative testing. Some will not pay for the procedure under any circumstances. Since we have no control over the criteria established by insurance carriers, we encourage you to contact your carrier before the first visit to our clinic to determine eligibility and the requirements for surgery. Unfortunately, we cannot set a date for surgery until all medical and financial screening has been satisfactorily completed.
The members of our weight management team will review your information and determine if you meet the preliminary criteria for surgery. Qualified candidates will be asked to come to our center for an in-depth discussion about their medical history and a physical examination. Those patients not thought to be appropriate candidates for the operation will be referred to medical personnel who can assist in medically supervised weight loss. Of those patients still considered eligible for surgery, most will require some testing to define the scope of their co-morbidities (diseases or problems caused by or accompanying their obesity) and/or to satisfy requirements set forth by insurance providers. These tests will be ordered during this visit. If you are determined to be a good candidate for surgery after all tests have been completed, we will seek approval for the operation from your insurance company. This approval process can take several weeks or longer to complete.
Once approval is received, you will be invited back to the clinic for a pre-operative visit. You must bring a close family member with you to this visit.
We need to know that you have adequate social support during the journey that you are about to take. This person will also help remember what we discuss in the event that you forget. It helps to have someone close to you later when you ask, “Now what did they say during that pre-op visit?” During the pre-operative visit, we will determine the best date for surgery, fill out the appropriate paperwork (including a consent form), and have you meet with the anesthesia team. If the anesthesiologists require no additional testing, your next visit with us will be on the morning of your operation.
If you normally use a CPAP machine at home, please bring it with you to the hospital to use as you recover.
You should also bring your medications. If our hospital does not stock your particular medicine, you may need to take it from your personal supply while you are here.
You should bring some slippers and extra loose-fitting clothes or a robe for wearing when walking around the hospital. Remember to bring any personal items and toiletries you may need. Some people bring a comfortable pillow.
You will also want to bring some reading material or quiet activities such playing cards, puzzles or needlepoint. Hospitals can be quite boring, with nothing to do except watching television and practicing your breathing exercises.
Upon arrival at the Day Surgery unit on the day of your operation, you will check in and change into a hospital gown. You will be given an injection just under the skin of your abdomen to help prevent blood clots. About an hour before your operation, you will be transported to the holding area of the operating room on the second floor. There, you will meet the anesthesiologist and a nurse from the operating room; an I.V. will be placed in your arm to give you antibiotics and anesthetic medications; you will then be transported to the operating room and then you will be moved to another bed. You will be given oxygen while other preparations are being made and your nurse will place some compression devices on your legs to help prevent blood clots. The anesthesiologist will then put you to sleep. A pump will be provided to administer pain medication as needed. Your surgeon will have already talked with your family about the operation and your status, and after a short stay in the recovery room, you will be transferred to a hospital room. You will not be allowed to receive anything by mouth until the next day. However, you will be helped out of bed two hours after the operation is over and be given an incentive spirometer to use to exercise your breathing every few minutes.
While everyone recovers at a different rate, the usual protocol is as follows. The day after surgery, you will be taken to the Radiology Department where you will drink a liquid contrast material while the radiology personnel take X-rays of your chest and abdomen. Once these films have shown that you do not have a leak, you will begin the oral intake as instructed. You will need to get up out of bed frequently throughout the day. You may disconnect the compression devices while walking, but they must be replaced when lying in bed, and the incentive spirometer should be used at least every 30 minutes. The shots beneath your skin will continue as long as you are in the hospital. The second day after surgery, the PCA pump will be removed and you will be switched to oral pain medication. Your diet and ambulation will progress as much as you can tolerate it. Typically, discharge from the hospital is two to three days after surgery. Upon discharge, you will be given a date and time to return to our clinic. The incentive spirometer will go home with you, and you should continue using it until your doctor tells you to stop. You will also be given a list of discharge instructions and information on how to contact us if necessary before your follow-up appointment. Because you won’t be permitted to drive for at least two weeks, you must have someone available to pick you up before noon.
Patients may be seen at any time the need arises, but usually patients are seen on the following schedule measured roughly from the date of their surgery:
Roux-en-Y Gastric Bypass
Adjustable Gastric Band
Every Six weeks
This is another decision that varies from patient to patient. The goal is usually six weeks following surgery. Some people are ready to go back to work sooner. It is best to wait until you feel completely comfortable with the demands of your particular job, as well as with the people you will come in contact with. The post-operative period can be a very emotional time for you. The stress of trying to speed your recovery to get back to work can actually make you feel worse.