Fact and research based paper on gastric bypass surgery. Should mention what it is, how it works (physiology), who should get the surgery, new technology, controversies including age or weight requirements for the surgery (how young is too young?), complications, side effects, and alternatives to surgery. Must include references to at least 7 primary sources. Must also include references to case studies and other research. Please don’t hesitate to ask me any questions you might have!
Gastric bypass surgery is a form of surgery that involves making of a small pouch in the stomach so that the food intake is reduced and a bypass is created to avoid absorption of the food into the duodenum (first part of the small intestines). It is also known as ‘bariatric surgery’ or “Roux-en-Y gastric bypass”. It can be performed by two methods, namely, the conventional method and the laparoscopic method (using a specialized tube-like instrument to view the inside of the abdomen and perform maneuvers). It is mainly utilized to treat obesity and involves stapling the stomach and connecting the pouch (that contains the upper portion of the stomach) to the second portion of the small intestine (jejunum). As the volume of the stomach is decreased, the individual feels that the stomach becomes full after consuming less amounts of food. As nutrients in the food are absorbed through the duodenum, and this structure is bypassed, the nutrients are lost and cannot be absorbed (Trowers Jr., 2005). Roux-en-Y gastric bypass operation has increased during the last 20 years and has been offering amazing results (LAPSF, 2007). In the US, about 35 % of the adult population is overweight.
In fact, obesity has crossed tobacco use as the number one contributing factor for morbidity and mortality. Obese individuals also develop several other associated medical problems such as hypertension, heart disease, diabetes, etc. Non-invasive treatment performed to treat obesity is hugely unsuccessful in the US, and hence many individuals are seeking surgery to help them reduce obesity. About 80, 000 such surgeries were performed in 2002 which increased to more than 100, 000 in 2003. Gastric bypass surgery was first introduced in the year 1967 by Mason et al. Alden further contributed to the Mason’s technique in 1977 by suggesting the use of staples (Simpfendorfer, 2005).
Some of the reasons for the sudden increase in the cases of gastric bypass (it has increased dramatically over the last five years):
- Use of laparoscopy – The outcome is more favorable, as the healing period, hospitalization, etc are reduced. Researchers are even looking at the possibility of conducting it on an outpatient basis.
- Sudden media hype – Especially experiences of the patients who have already undergone the procedure.
- Patients are receiving a lot of information of this procedure through the internet.
Before the surgery is conducted, a complete history is taken to ensure that and a few tests are performed. The individual is thoroughly evaluated and the mental status is also determined to ensure that the individual can go through the process of the surgery (not having any major mental problems). If the individual is not mentally prepared, the surgery should be either not is performed or an alternative may be required. A few precautions have to be taken to ensure that the individual is physically and mentally prepared for the surgery. The individual is nutritionally advised about certain measures (before and after the procedure), so that the surgery is effective in reducing body weight. If the nutritional measures are not followed, the entire process may not be beneficial (Trowers Jr., 2005).
Prior to the procedure, the entire process, the risks involved, the benefits, and the available options should be described, and the individual should give consent for the procedure (informed consent). The individual should get admitted to the hospital for a few days before and after the surgery (Mayo, 2006). The pre- and post-operative duration for hospitalization is much less in case of laparoscopic surgery compared to conventional surgery (Ricciardi, 2006). The entire process of the management of the obese patient is performed by a team of healthcare professionals including physicians, nutritionists, surgeons, psychiatrists, and gastroenterologists. In all cases, surgery is performed only if the benefits are clearly greater than the risks involved. The individual may have to bring about certain modifications in diet, fluid intake, daily routine, exercises, smoking and medications (Mayo, 2006).
The procedure can be performed by two methods, namely, the laparoscopic method and the conventional method. The conventional bypass surgery, frequently known as “Roux-en-Y gastric bypass” involves connecting the upper portion of the stomach to the lower portion of the small intestine. The surgery is performed in two stages. In the first stage, the stomach is divided to create a small pouch in the upper portion to hold about an ounce of food. Once this is done, the small intestines are divided and are connected to the upper end of the stomach. The mucosa of the stomach and the small intestines are sutured together, and the new stomach measures only about the size of a walnut (Mayo, 2006).
Hence, during the process of digestion, the food will bypass most of the stomach and the duodenum (where the nutrients are usually absorbed) and hence, the food would directly enter into the second portion of the jejunum, where only some of the nutrients are absorbed, and the rest are excreted out. The open end of the stomach is sutured together and this structure would be still performing its function of secreting gastric fluids that help in digestion. These fluids are released into the intestines which later help in the digestive process. The end of the duodenum is attached to the jejunum which will help to release several enzymes and other secretion such as bile, pancreatic fluid and hydro chloric acid. This will help the body to absorb certain essential substances from the food such as vitamins, minerals and other substances.
About three to four feet of the small intestines are bypassed (the small intestines are usually about 20 feet long) (LAPSF, 2007). The new food pipe created that bypasses the stomach and the first portion of the small intestines is known as ‘Roux limb’. The manner, in which the end of the duodenum is connected to the Roux limb, resembles a Y-shape and is known as ‘Roux-connection’. The digestive tract may still be unable to absorb certain vital nutrients required by the body, and hence, this individuals condition should be closely assessed (Trowers Jr., 2005).
Gastric bypass surgery can also be performed using a laparoscope. In this method, a small keyhole incision is made on the abdomen wall through which the laparoscope is inserted. Once the instrument enters the abdomen, the interiors can be visualized and the incision can be made to disconnect the upper end of the stomach from the middle and the lower end. The incision is also made just after the duodenum and the upper end of the stomach is sutured to the jejunum using the special tip present in the laparoscope. Compared to conventional surgery, laparoscopic surgery offers better and faster healing. However, the surgeon performing the surgery should have a high level of competency and skills. In certain extreme cases, it may not be advisable to perform laparoscopic surgery (Mayo, 2006).
Basically, weight losing surgeries are of three types, namely, restrictive surgery, malabsorptive surgery and combination surgery. In restrictive surgery, procedures to reduce the size of the stomach are performed. In malabsorptive surgery, the flow of the partially digested food from the stomach to the intestines is altered such that the nutrients are not absorbed effectively. Combination surgery is a process in which the size of the stomach is reduced and malabsorption by the intestines is induced, so that the individual tends to lose weight. Roux-en-Y gastric bypass is a combination surgery procedure. Hence, the individual can more effectively lose weight.
Another procedure known as ‘Lap-Band surgery’ involves the placement of a band on the upper portion of the stomach such that a small pouch is created. This reduces the amount of food consumed and hence the individual feels that the stomach has been filled up with a little food. Individuals who are treated by Lap-Band Surgery may develop several complications such as nausea, vomiting and gastro esophageal reflux (Trowers Jr., 2005).
Another reason why gastric bypass surgery helps to reduce weight is that certain substances which are released by the gastrointestinal system to control appetite are increased and brings about weight reduction. One such example is neurotensin which also helps to reduce gastric and intestinal motility, and decrease gastric secretions. Clinical trials conducted demonstrated that gastric bypass was more effective than gastric banding, as neurotensin levels were higher in gastric bypass compared to gastric banding. This suggests that neurotensin plays a major role in reducing obesity especially when gastric bypass is performed. The exact mechanism by which neurotensin acts is not known and needs to be researched further (Christ-Crain, 2006).
Gastric bypass should not be performed in all cases that require loss of weight due to obesity. As there are a lot of complications associated with the surgery, the benefits should be weighted with the risk, and only if a clear benefit exists, the surgery should be performed. Usually, the gastric bypass is indicated if the individual has a severe and resistant form of obesity that does not respond to standard therapy with diet and exercise. There are several problems associated with gastric bypass and the individual is at a constant risk of vomiting. Besides, lifestyle changes are required to ensure that safety is assured.
Gastric bypass surgery is usually required if the BMI is greater than 40. This is an extreme form of obesity. It may also be required in individuals who have a BMI of 35 and develop systemic illness in which it is essential to lose weight (such as type 2 diabetes, coronary artery disease, hypertension, high cholesterol levels and obstructive sleep apnea). However, it is essential that the individual maintains a healthy diet and is physically active. Studies suggest that Gastric bypass surgery is more beneficial when performed with other measures. The individual should ensure that lifestyle changes are enabled (Trowers Jr., 2005).
There are several complications associated with gastric bypass surgery. Some of the complications may be associated with the actual surgical procedure, use of anesthesia during the surgery or the complications of bypass procedure. Some of the complications associated with the surgery include bleeding, infections, gallstone formation, gastritis, nausea, vomiting, deficiency of minerals and vitamins, calcium deficiency, etc. The scars formed at the surgical site may get infected. Besides, complications affecting the lungs and the heart may develop from the use of anesthesia. Other complications that may develop following the surgery include diarrhea, bloating, dizziness, tiredness, fatigue, loss of hair, feeling cold, etc (Trowers Jr., 2005).
Some individual who are in poor general health, those with certain medical conditions or who may be slight elderly, may not tolerate the surgery and may meet with a fatal outcome. Some individuals are at the risk of developing blood clots within the blood vessels of the legs. This results in pain and swelling in the legs. Some of these clots may be dislodged and may get deposited into vital blood vessels of the lungs, resulting in a condition known as ‘pulmonary embolism’. The individual develops several problems such as breathlessness, chest pain, and even death. For this reason, some of the individuals are administered anticoagulants after the surgery. In some individuals, there may be some amount of seepage at the site of stapling the stomach (anatomical leakage). Minor cases can be treated by administering antibiotics, whereas in severe cases, surgery may be required. Some individuals are at the risk of developing pneumonia, due to the application of excessive weight on the chest. Another complication seen rather infrequently following gastric bypass surgery is the development of an obstruction between the new connection between the stomach and the intestines. Such individuals may require the placement of a specialized tube down through the mouth so that this obstruction can be dilated.
Otherwise, a corrective surgery can be performed after sometime so that the gap can be enlarged. Other complications that can also develop following gastric bypass surgery include dehydration states, bleeding due to stomach ulcers, hernia at the place of surgical incision and intolerance to certain food. Some individuals are also at the risk of developing a condition known as ‘dumping syndrome’ in which the food passes very rapidly through the new stomach and small intestines resulting in the development of several symptoms such as nausea, vomiting, dizziness, diarrhea, tiredness, and sweating (Mayo, 2006).
After the surgery a few precautions should be followed to ensure that the recovery is smooth and the risk of complications is lower. The individual should be hospitalized for a few days after the surgery. It may require about four to five days of hospitalization. The individual should consume analgesics and the antibiotics, and should be on a liquid diet so that nausea and vomiting may not be present. After two or three days, the individual can move about slightly. For many weeks after the surgery, the individual should stay on a diet basically liquid or semi-solid in nature which can be easily digestible. As the stomach can stretch to a lower extent following the surgery, the individual should adapt to this change by consuming lesser amounts of food. Initially, the individual may have to consume only a few teaspoons of food at a time. Slowly over a period of time, the wall of the stomach will expand, slightly increasing the amount of food which can be consumed.
After a certain period of time, the individual can consume a cup of food that has been thoroughly chewed at one time. The physician has to be continuously evaluated to determine any deficiency in vitamins and minerals. Potentially, deficiency states should be avoided by administering the appropriate vitamin or mineral as supplements. The supplements are usually not absorbed properly because the food tends to pass through the intestines at a rapid rate compared to normal. The individual should consume smaller meals more frequently, than a few larger meals. During the eating process, the food should be chewed properly to ensure that further digestion can be done in the body. Some individuals should avoid consuming excess of fat, sugars and alcohol in the diet. The individual should avoid consuming solid and fluids at one time. A gap of at least 30 minutes should be left when these two types of foods are consumed.
The individual should also avoid consuming junk foods, fried foods, food containing high amounts of fats and sugars (such as candies and cakes). The individual should perform adequate physical activities on a regular basis. This would certainly help in reducing weight following the gastric bypass procedure. Light exercises can be initiated one and a half month after the surgery. Initially, the individual should start by taking small walks and gradually light exercises can be performed. The individual can also join a support group to help in reducing obesity in a more reasonable manner (Trowers Jr., 2005).
Roux-en-Y surgery can provide certain amazing results. About 10 pounds of the body weight are lost every month. Usually, most of the body weight is lost during the first few months after the surgery (Trowers Jr., 2005). The individual may lose about 50 to 60 or even 70 percent of the excessive body weight within the first two years after the surgery. Only those individuals who maintain changes in lifestyle would benefit from the surgery. Without diet and exercises, gastric bypass may be less effective in reducing the obesity (Mayo, 2006). The individual may lose weight because lesser amounts of nutrients are consumed in the diet and also because the stomach feels full on eating lesser quantities of food. Individuals who have undergone Roux-en-Y gastric bypass should stick to certain dietary recommendations. They should consume not more than 800 calories per day for the first one and a half year after the surgery. For the next three year, they should not consume more than 1200 calories per day. As dumping syndrome is a common complication following Gastric bypass, they should avoid eating excess sugars and fats in the diet (LAPSF, 2007).
A study was conducted to review the literature available on the Cochrane database regarding the effects of surgery on obesity. The study included several RCT’s and non-Randomized Clinical trials that were utilized to compare the effect of surgical and non-surgical methods of treating severe obesity. Only individuals above the age of 18 years, and having a BMI of 40 and above (35 and above in the case of individuals with certain systemic disorders), were included. They were monitored closely for about a year. About 18 clinical trials which met the above mentioned criteria were able to be included in the study. The study demonstrated that compared to non-surgical methods, surgery were only slightly more effective in bringing about long-term weight loss (for over 8 years). However, the risk of adverse effects was greater in surgery than in non-surgical techniques (HSTAT, 2003).
In another study, the effect of horizontal gastroplasty along with diet was compared to diet alone. The individual’s weight was compared at 6 months and 2 years. It was observed that in both groups, in the initial stages, there was not much difference in the weight loss. Both surgery and non-surgical therapy had produced an almost equal weight loss. However, when their weights were compared at the 2 year interval, the weight loss was greater in those who underwent surgery, compared to those who did not undergo surgery. Another trial compared the effect of surgery and medical therapy on obese individuals belonging to a Swedish group. It was found that on an average those treated with surgery lost about 20 kilograms of weight, whereas those treated medically did not have much of weight loss.
Also it was found that Roux-en-Y gastric bypass was more effective than other forms of surgery such as banded gastroplasty and horizontal banding. The study demonstrates that the difference between weight loss in the surgical and the non-surgical treated groups was greater than 10 kilograms (HSTAT, 2003).
The individual undergoing Gastric bypass should be told of the benefits and risks involved with the surgery and should be told of the alternatives available. This is a part of the informed consent process, to make sure that the individual has greater control over their body. Although, Roux-en-y gastric bypass is the most common weight losing surgery, there are other forms of surgery which should be told to the individual including adjustable gastric banding, vertical banded gastroplasty and biliopancreatic diversion. In adjustable banding surgery, the surgeon utilizing a laparoscope places an adjustable band that separates the stomach into two divisions or pouches. This band is adjustable and the surgeon has to only tighten it for it to work. As two pouches are created, the capacity of the stomach to hold greater amounts of food is reduced and hence the individual does not consume larger amounts of food.
In vertical banded gastroplasty, the surgeon using a surgical stapling device staples or divides the stomach into two portions, namely the upper portion and the lower portion. The upper pouch accommodates only a limited quantity of food and empties into the lower pouch. Overall, this form of surgery is not as effective as gastric bypass. In biliopancreatic diversion, a surgery is performed on the individual in which a portion of the stomach is removed and the remaining portion is directly attached to the portion of the small intestines that lies beyond the duodenum and the jejunum (usually food is absorbed in these regions). Although, this procedure is effective in reducing weight, it is usually not performed because the risk of certain complications such as malnutrition syndrome, excessive weight loss and vitamin and mineral deficiencies are very high (Mayo, 2006).
The mortality rates following gastric bypass is about 0.3 to 1 %. Some of the frequent causes of fatalities include leakage into the peritoneal cavity, pulmonary embolism, cardiac problems, abscess formation inside the abdomen, etc. The chances of fatal outcomes were higher in individuals above the age of 50 years. On the other hand, the chances of serious complications were between 15 to 24 % such as abdominal hernias, hematoma formation, pulmonary embolism, wound infection, hemorrhage, marginal ulcers, obstruction of the small intestines, atelectasis, etc. Individuals who develop prolonged vomiting in relation to gastric bypass surgery are at a risk of developing Wernicke’s encephalopathy.
Some individuals are at the risk of developing depression in association with the surgery. The depression may in fact be so severe that the individual may stop eating and may lose weight. However, in such cases, it would not be healthy weight loss and the surgery in fact would be a failure. Anatomical leakage is another complication that is frequently seen in individuals who have undergone gastric bypass surgery. The risk of leakage was relatively higher with laparoscopic surgery (about 5 %) compared to conventional surgery (1 to 2 %). Bowel obstruction and intra-abdominal hernias are other complications of gastric bypass. Marginal ulcer can also occur in about 2 to 10 % of all surgery, and is relatively higher in individuals who have H. pyroli present in their bodies.
Such incidences can be reduced by eradicating H. pyroli preoperatively before the surgery. Individuals who develop dumping can be treated by administering octreotide injections. Nutritional deficiencies are also common in individuals with gastric bypass especially iron and vitamin B12 deficiencies, and the individual is at the risk of developing anemia (Townsend, 2002). Individuals who have laparoscopic surgery performed are at lower chances of developing wound infections, splenectomy and hernias. The chances of stenosis, bowel obstruction and hemorrhage were higher in individuals with laparoscopic surgery (Townsend, 2002).
Sciopinaro et al reported mortality rates arising from bilopancreatic diversion to be about 0.66 % and the incidences of complications to be about 1.2 to 2.8 %. Further the individuals who develop bilopancreateic diversion are at a slightly higher risk of developing protein malnutrition (Townsend, 2002). Duodenal switch is another complication that develops from gastric bypass. Anthone et al demonstrated fatality rates of about 1.4 % in their study (Townsend, 2002).
Frequently, surgeons have to perform repeat operations for failed gastric bypass surgery or the development of certain complications such as stenosis, etc. Some surgeons may correct the defect that leads to the complications, but may not actually ensure that the weight loss is continued. The strategy for weight loss should be reassessed following the second surgery. The risk of several complications such as infection, anatomical leakage, blood transfusions, etc is higher with the second operation. On the whole, gastric bypass surgery has failure rates of about 10 %. These include several cases of medical post-surgical complications, side-effects, inability to cope with a new lifestyle, etc (Townsend, 2002).
The initial results suggested that there were both short-term and long-term results associated with the surgery. Between 5 to 15 years, the individual could lose on an average about 49 to 62 % of their excess body weight. There has been an increase particularly in the laparoscopic procedure for gastric bypass. It has several advantages including reduced period of hospitalization, reduced problems with the lungs, faster recovery, greater safety, reduced pain after the operation, reduced incision hernias, reduced blood loss and need for transfusions, faster performance of normal activities, etc. One of the main complications associated with laparoscopic gastric bypass includes obstructions of the bowels (Simpfendorfer, 2005). Another study conducted by Ricciardi et al (2006) demonstrated that laparoscopic gastric bypass was performed less frequently compared to conventional gastric bypass (83.7 % is to 16.3 %). Several problems such as extended duration of stay in the hospital, delayed wound healing, fatal outcomes, digestive tract, lung and cardiovascular complications, etc, was less with the laparoscopic approach compared to the conventional approach (Ricciardi, 2006).
A study was conducted by Pope et al (2006) to determine the effect gastric bypass had over the lifespan of the individual. The study was conducted in obese patients who had a BMI of 40 and above and who were greater than 40. The data was obtained from studying the baseline mortality risks, epidemiological results and outcomes of the surgery. An obese individual above the age of 40 years gained about 2.6 years on an average following gastric bypass surgery. The number of years gained varied, but did not depend much upon age and sex (Pope, 2006).
Another trial was conducted by Christou et al (2006) to determine the long-term effect gastric bypass surgery had on obese patients. The individuals were closely monitored for about 10 years. Individuals with severe forms of obesity lost more weight compared to those with the milder forms following gastric bypass surgery, when studied after 2 years. The chances of failures and reduction in the effectiveness were higher after 10 years than at 5 years. The failure rates after 10 years was higher in those with severe forms of obesity (about 35 %) compared to those with the milder forms of obesity (Christou, 2006).
References
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- Christ-Crain, M., Stoeckli, R., Ernsth, A. Et al (2006). “Effect of Gastric Bypass and Gastric Banding on Proneurotensin Levels in Morbidly Obese Patients.” Journal of Clinical Endocrinology and Metabolism, 91(9).
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