Revisional Bariatric Surgery
Bariatric surgery offers patients a tool to help them lose weight and keep it off. With an ever increasing number of bariatric operations being performed each year, there are many patients that are now asking, “what if my tool is broken?” This leads to discussions about revisional bariatric surgery.
For many surgeons and patients alike, this brings us back to the very beginning of the discussion of bariatric surgery and the reason it is done. We must remember that these surgeries save lives. There is an 89 % reduction in the risk of death over five years for those patients who had bariatric surgery.
What is Success or Failure?
Do we define success as a certain amount of excess weight loss, health problems resolved, quality of life improved or any combination of these? There is no firmly established definition for success, but most surgeons define good weight loss as losing 30% excessive weight with the resolution of one or more co-morbid conditions, such as diabetes or hypertension. Expectations must be managed well. The average adjustable gastric band patient may expect to lose 47-80% of their excess weight, with realistic expectations at the lower end of this range. The average bypass patient may expect to lose 60-90% of their excess weight, with realistic expectations at the lower end of this range.
Reasons for Failure
When a patient is not feeling successful after weight loss surgery, there are three potential problem areas: medical, psychological and educational. There may be problems in any one or more of these areas and they all have to be addressed to ensure a comprehensive resolution to the problems at hand. A comprehensive bariatric program will begin to evaluate the “broken tool” by examining the integrity of the surgery and the patient’s compliance, education and psychology.
Medical problems include structural or mechanical problems and nutritional deficiencies. Bariatric surgery works by restricting calories, causing malabsorption or altering gut hormones that control appetite and glucose utilization. Patients must fully understand how their particular operation is affecting them. Likewise, they must understand the basic nutrition principles of fat, carbohydrate and protein catabolism.
Metabolism and Calories
We burn calories just sitting on the sofa watching television because our hearts are beating, our diaphragms are contracting and our brains are thinking. This “inaction” takes action and so burns calories when we’re at rest. This is called our basal metabolic rate (BMR). The rate at which we burn calories through activity (e.g. moving, walking, exercise, etc) is termed active metabolic rate (AMR). Together, these two rates determine the total number of calories our bodies will use per day. If we take in fewer calories than this, we lose weight. If we take in more calories than this, we gain weight.
We can certainly control our AMR by determining how much and how long we exercise. Exercise also positively affects our BMR. The more we exercise, particularly resistance training, the more muscle mass we will have. More muscle means more calories are required to sustain that muscle and so you will burn more calories at rest. To maintain this muscle, however, also requires that we eat a good amount of protein in our diet, thus limiting the sugars and fats. Our body size, gender and testosterone levels play an important role in the amount of muscle we can build.
No matter how high our AMR+BMR is, it is really difficult to burn as many calories as we can eat. Today’s society provides a wide variety of calorie dense foods. For example, a fast food hamburger, fries and a coke averages 1300 calories. To burn this many calories with exercise would take about 4 hours of brisk walking! We are what we eat. The fewer calories we take in, the more weight we will lose (or less weight we will gain). This is why bariatric surgery is so effective. The restriction or malabsorption of calories limits the intake. Food selection on the part of the patient is critical.
Nutritional Education
Patients must be educated on the appropriate foods to eat and the appropriate amount of these foods to eat. Educational problems are address with nutritional classes, assessment of preoperative weight loss goals and good follow up. Patients should always eat protein first, focusing on solid food (chew your calories), and remain hydrated at all times.
Emotional and Psychological Issues
Finally, psychological problems include emotional eating or food addictions. Even with an appropriated adjusted band or effective gastric bypass, a patient can fail to lose weight, for example, if they continue to binge eat or rely on “comfort” foods in times of stress. Patients must be psychologically committed to the process of weight loss. There is no “easy” button. Diet and behavior modification are just as important as physical restriction. Without the appropriate mindset, bariatric surgery is set up for failure.
Issues Resulting from the Procedure
Assuming that the patient is eating well, understands the basics of nutrition and exercise, and has no major psychological issues, and then the surgeons will begin to focus on mechanical problems with the surgery. Problems are assessed based on the original operation.
Band patients may experience slips, erosions and hiatal hernias; we may have to consider the amount of restriction the patient has; and, if all else fails, we may discuss converting the band to a bypass or sleeve gastrectomy. If a band slips, the patient is usually in pain, has nausea and vomiting, or may lose all their restriction. Surgery is required to fix this. Sometime the band can be repositioned, but sometime it has to be replaced. If another operation is agreed upon, the band is removed at the time of the new operation. If the band is eroded into the stomach, it must be removed because it is infected. No other operation should be done at that time. After a couple of months, another operation can be done. It is generally felt that another band should not be placed because of the high incidence of having another erosion. Sleeve gastrectomy or bypass operation is usually preferred.
Gastric bypass operation (roux-en-Y gastric bypass) is the gold standard operation for weight loss and has had a tremendous amount of success in its more than 50 years of use. Nevertheless, failure rates are reported as 1-5%. Most common complaint is weight regain after several years. 20% regain is not uncommon but depends heavily on the patient’s commitment to consistent diet and exercise. Again, successful bariatric surgery requires lifelong changes. Nonetheless, there are reported problems with pouch dilation, increased absorption of the intestine through adaption, and other complications of the operation that can lead to problems. To determine the problem, several tests may be ordered such as scopes to look in the stomach and x-rays to see if there are abnormal connections between the pouch and old stomach. If the pouch is too big there are many options such as endoluminal therapies to plicate the pouch and make it smaller, placing a band around the pouch, or surgically reducing the pouch size by removing portion of it. If the pouch seems small, then the patient may need more malabsorption. This can be accomplished by going to the operating room and making the bypassed limb longer. These maneuvers may help a patient lose an addition 15-25% of their excess weight (i.e. another 6-7 BMI points) for the pouch banding and 25-40% for added bypass length. Revising gastric bypass operations has a higher risk of complications. The risk of excessive scarring causing a tight passage of food can be increased from 5% to 15%. The risk of leaking from a staple line increases from 0.7% to 15%, and the risk of bleeding increases from 0.8% to 4%.
Some patients may present with chronic abdominal pain after this operation. If they have lost a significant amount of weight, there should be a high suspicion of internal hernia. This is when the bowel protrudes through an internal space that can cut off the blood supply to the bowel. Sometimes a CT scan can diagnose these problems, but the best test to diagnose and treat the problem is a diagnostic laparoscopy. This involves going to the operating room, putting the patient under general anesthesia, and inserting a camera in the abdomen. If the hernia is found, the bowel can be pulled out of it and the defect closed with permanent sutures to prevent it from happening again.
In summary, we must keep in mind that obesity is a complex disease and there is no simple, one way to treat it. Revisions will be necessary and require extra commitment from the bariatric team and patients. We must all become less focused on weight and pounds and more focused on improved health and quality of life. Surgery is not a cure but a tool. Revisions are risky and we must be clear about the risk and benefits. The Minimally Invasive Surgeons of Texas bariatric team is dedicated to finding the best way to help our patients find success in the safest and most effective way. We are focused on the medical, surgical, nutritional and psychological treatment of this disease. This holistic approach provides the best chance for successful revisional surgery.