Laparoscopic Gasrtic Bypass

Laparoscopic Gastric Bypass

First Some History Bariatric Surgery, surgery for the purpose of inducing weight loss, has been around for a very long time but has gone through extensive evolution. Obesity surgery can be grouped into two broad categories. Restrictive procedures somehow try to restrict the amount of food a person can eat, while absorptive procedures somehow limit the amount of food a person can absorb.

The earliest bariatric procedures were purely attempts to completely bypass the intestine and thus severely limit absorption of calories. It was later recognized that certain parts of the intestine were required to absorb specific nutrients necessary for survival. Additionally, bacterial over growth in the de-functionalized intestine led to build up of toxic by products resulting in severe illness from liver failure and very high mortality. Needless to say, this procedure is no longer performed.

Restrictive procedures attempting to limit the size of the stomach or to create a tight passage through which food must travel have also been around for a while and continue to develop. Though generally easier to perform technically and with lower early risk, the results of these procedures in terms of sustained weight loss are not as good as with gastric bypass. Additionally, the device or material used to restrict the stomach has a risk of eroding into the stomach, thus creating a potential delayed complication that is a challenge to deal with.

Gastric Bypass has also undergone much evolution. The term itself is a bit of a misnomer in that it does not completely bypass the stomach. The goal of the procedure is to create a very small pouch of stomach with a semi-restricted outflow so that when a person consumes a small amount of food he/she senses that they are full very early. Additionally, a portion of the intestine is removed from the path of digestive enzymes, so that it serves only as a conduit for food but no absorption can occur. Thus, this procedure has both a restrictive and absorptive component. Originally, this procedure was performed without dividing the stomach. The pouch was created with a special stapling device that would place several rows of staples across the stomach without cutting between the staples. Over the long term, however, no healing occurred between the lining of the stomach so the integrity of the pouch was solely dependent on the staples. There was a very significant incidence of staple line failure which would result in unacceptable weight gain in the patients.

Patient Selection Bariatric surgery is extremely rewarding for both the patient and the surgeon, but it is not to be undertaken lightly. It requires extreme motivation and understanding on the part of the patient to achieve the desired result of dramatic weight reduction with a very low complication rate. A surgeon performing this type of surgery must be very patient with his patients and must invest an enormous amount of time on patient education and insisting on compliance. If this mixture cannot be achieved, the likelihood of success is low and the risk is high. This is not a hernia operation!

All prospective patients considering a bariatric procedure are initially evaluated with a detailed history. They are weighed and their BMI is calculated. The history taken should include a detailed assessment of the presence of obesity related co-morbidities, family history of obesity, work and family situation as well as the usual elements of a medical history. Indications for surgical intervention for obesity are a BMI of greater than 40 or a BMI of greater than 35 with major obesity related co-morbidities.

Next they are counseled as to the life change they are undertaking. Dramatic weight reduction can have dramatic impact on your social and professional life as well as on your general prospects for good health and longevity. Such change, however does not happen over night and requires hard work and dedication. Obesity surgery is a tool and if used appropriately can help one achieve lifelong life enhancing change. If used inappropriately or in the insufficiently motivated patient, the likelihood of failure and complications is high.

I stress all of this because most patients do not want to hear what comes next. No, you are not going to have surgery next week! Prior to planning a bariatric procedure all patients must first go through a trial period of dieting and exercise under the guidance of a physician. Most insurance companies insist upon this prior to authorizing payment for surgery. This is one of the very rare instances in which I agree with them. Additionally, consultation with a psychiatrist or psychologist is usually necessary first to rule out any major psychological factors that may interfere with a patient's ability to follow through on this undertaking and secondly, to assist in behavior modification exercises which may help in controlling the triggers which lead to overeating or non-compliance.

Other consultations may also be necessary down the road. An endocrinology evaluation is often necessary to rule out any hormonal problems that may be contributing to obesity. Certainly a patient who is hypothyroid is not well served by undergoing major surgery before this problem is adequately treated. Pulmonology and Cardiology evaluations may also be warranted to assess the respective pulmonary and cardiac risks for surgery. Additionally, a sleep study is often necessary to diagnose sleep apnea, which is frequently associated with obesity. Other consultations may be warranted depending on the specific patient.

At the first encounter I ask all patients to maintain a dietary diary. The diary should included every thing that they consume and should note its quantity, mode of preparation (baked, fried etc.) and anything that is put on it (butter, sour cream). This will be used as a tool to aid one in making modifications and adjustments to limiting caloric intake and improving the quality of food that is consumed. The idea is to construct a diet that one can live with for the rest of one's life. While some of the commercially promoted diets (Weight Watcher's, Atkins), if adhered to, can result in very significant weight loss, the moment the diet is discontinued weight is usually regained with a vengeance.

The next appointment is two weeks later at which time the diary is reviewed and the patient is referred to a dietician for dietary counseling, a physical therapist for exercise tolerance and exercise program, and a psychologist or psychiatrist for routine screening and behavior modification. All of the principles already mentioned are continuously reinforced and patient compliance and motivation are stressed. This process is repeated monthly with continued input from the consultants.

It is understood that 97% of patients who achieve the status of Morbid Obesity will fail to lose weight with dieting, exercise and behavior modification. At some point during the program, we shift gears and more directly discuss surgery. At this point the emphasis is changed from attempted weight control with dieting, to understanding the dietary changes that will be mandated by the surgery. Additionally, the patient must be educated on potential long term consequences of surgery and the avoidance of those complications. The details of this are discussed below.

Laparoscopic Gastric Bypass Surgery Finally, what you clicked on this page to read about in the first place! The patient is admitted the morning of surgery. The procedure requires General Anesthesia and all of the usual monitoring devices so associated.

First the gastric pouch must be sized. This is done by passing a balloon through the mouth and down into the stomach. The balloon is then inflated with about 50cc of air. The stapling device which creates the anastomosis has two parts. The small distal head called the anvil must somehow be introduced into the stomach with its post piercing the stomach wall at the desired site. There are several techniques for doing this and the choice of which technique is really surgeons preference. One of the techniques requires endoscopy, which means the surgeon has to break scrub and pass an endoscope from the anesthesia side of the field into the patients mouth and into the stomach. Though this is a good technique that works well, it takes more time and requires additional equipment. I prefer the more direct approach of passing the anvil through a separate opening in the stomach and directing the post to where I want it.

The stomach is then divided with a stapler around the balloon or around the anvil depending on the technique chosen to place the anvil.

Next, the small intestine is divided with a special stapler about 20 or 30cm beyond its entrance point below the colonic mesentery. The limb to be attached to the stomach, referred to as the Roux limb is then measured. The length of the Roux limb is varied from 75cm to 150cm according to the patients BMI. This segment of intestine will not function in the absorption of nutrients as it has been removed from continuity with the flow of pancreatic and biliary enzymes necessary for digestion.

Next, the cut end of the intestine is reconnected to the Roux limb at the chosen length.

The cut end of the Roux limb is then connected to the stomach by mating the stapler with the anvil that had been previously placed. This results in an open end of the intestine which is then resected and closed. The connection between the stomach and Roux limb is then tested for leakage by introducing air through a tube placed through the mouth into the pouch with the anastomosis under water and the Roux limb occluded. (Like you would test a tire for a leak) Some surgeons inject blue dye into the stomach to look for leakage and yet others perform an endoscopy to check for leakage. The exact choice of method is really up to the surgeon's own experience. Any potential sites for internal hernias are closed and the procedure is complete.

In hospital recovery takes 2 - 4 days. The day after surgery, a routine x-ray is done with the patient swallowing gastrograffin, a water soluble contrast material. If the x-ray does not reveal a leak and the patient has no clinical signs of a leak, the patient may be started on clear liquid diet, no carbonation, 1oz every 1 - 2 hours. This is advanced quickly as the patient tolerates and most patients are sent home on Carnation Instant Breakfast (or equivalent) 4oz every hour with a multivitamin daily.

Results Weight loss is most rapid during the first 6 months but continues for about a year, or as long as 18 months. Some patients will regain some of the weight later on but the expected end result is an 80% reduction in excess body weight. For example, a person 5 foot 6 inches weighing 250 pounds has a BMI of 40, which is morbid obesity. The upper limit of normal for that patient is about 150 pounds which is a BMI of 25. Following laparoscopic gastric bypass that patient would be expected to lose 80 pounds giving him/her a BMI of 27, which is still mildly overweight, but no longer a health risk.

Obviously, you do not live the rest of your life on Carnation Instant Breakfast. After about a week or so a puree diet is begun and this too is advanced to solid food after about 3 weeks or one month. This is all done under the watchful eye of the dietician and the surgeon. At this point, failure to adhere to this regimen can have disastrous results. Over the first year, certain vitamin and nutrient levels in the blood must be monitored as well as the blood count.

After extreme weight loss some patients will find the need to seek out a plastic surgeon for removal of excess skin and redundant tissue around the mid body, arms and legs. Should this be necessary, there are some excellent, well established procedures for achieving a good cosmetic result.

The biological as well as the psychological effect of dramatic weight loss is usually markedly beneficial. Diabetics become much easier to control and may in fact become non-diabetic. The same is true for patients with hypertension. Sleep apnea usually disappears and the patients feel much better when they suddenly can get a full nights sleep. Additionally, the spouses of these patients feel better because the snoring issue is resolved. Reflux disease, if present, generally improves or disappears as well as chronic headaches. Arthritis becomes less severe and easier to treat. Patients with advanced arthritis in need of joint replacement, but considered non-candidates because of their extreme obesity, will now be suitable and following that procedure can look forward to years of pain free activity. The social and professional impact of such weight loss can be profound and life altering.

It is these results that make bariatric surgery so rewarding for the surgeon as well as the patient. However, as I have iterated repeatedly, with high reward comes high risk. It is careful patient selection and preparation that keeps these risks to a minimum.

Risks (short term and long term) The short term risks of this procedure are those risks related to the surgery itself. Because many of the patients undergoing this type of surgery have, often multiple, co-morbid conditions the risks of anesthesia and surgery are already higher than in the non- morbid obese population. Obviously, the surgeon performing this type of surgery must have exceptional experience at advanced laparoscopic procedures.

The surgical risk that I am most concerned about is that of leak at the anastomosis between the stomach and the Roux limb. The risk is highest here because it is being performed with a very small caliber stapler and there is very little margin for error. At the conclusion of the procedure this are must be carefully checked by one of the methods mentioned. Nevertheless, in a small number of patients a leak will develop at this point within the first few days after surgery. One must maintain a very high index of suspicion and be prepared for a return to the operating room should any of the clinical signs of a leak develop in spite of radiologic evidence to the contrary. A delay at this point can result in an easily correctable problem becoming a life threatening one.

In the first few weeks after surgery, patient non-compliance is probably the leading cause of major leaks. It takes about three weeks for healing to have occurred to enough of an extent that distension of the gastric pouch will not cause a leak. Patients who will not adhere to the guidelines and insist on pushing the envelope may precipitate a catastrophe during this period of time. This is why I stress careful patient selection and adequate preparation.

Dumping syndrome is a condition in which undigested food is allowed to rapidly enter the intestine from the stomach. This can result in symptoms such as nausea, vomiting, bloating, diarrhea, dizziness, weakness, shortness of breath. This can occur in following many types of stomach surgery, but is common after gastric bypass of the patient consumes meals high in sugar content too rapidly. The patient must be well educated as to the symptoms of dumping, so as to recognize it and avoid it.

Stricture or narrowing at the anastomosis is another delayed complication that some patients may encounter. The connection between the stomach and the Roux limb is created to be small so as to restrict gastric emptying and prolong the sense of fullness. Sometimes this connection may scar down and become too narrow to empty at all. Patients so afflicted may begin to vomit repeatedly. The treatment, once the diagnosis is made, is to dilate the anastomosis using special endoscopic techniques and balloon dilators. Some patients may require multiple treatments. It is rare for repeat surgery to be necessary.

Finally, because of the re-routing of normal anatomy that is the nature of this procedure, the intake and processing of certain vitamins may be interfered with. Vitamin supplements are given routinely but special attention must be paid to Vitamin B12, Folate, Iron and Calcium. Levels of these substances should be monitored frequently during the first year after surgery and then periodically, thereafter. Patients may require periodic supplementation of their oral vitamins with Vitamin B12 injections though this is not often required.

I hope you have found this article both educational and entertaining. It is not my intent to scare you or discourage you. I do believe, however, that the best way of achieving success in an endeavor such as this is to assure that you have all of the facts. Success in bariatric surgery requires a close partnership between the patient and all of the treating physicians. As always, I invite any questions that you may have.

Steven P Shikiar, MD, FACS email