Surgical intervention for the severely obese

BEST

Baillière’s Clinical Endocrinology and Metabolism Vol. 13, No. 1, pp 149–172, 1999

B A I L L I È R E ’ S

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PRACTICE & RESEARCH

Surgical intervention for the severely obese Robert J. Albrecht

MD

Resident in Surgery

Walter J. Pories

MD*

Professor of Surgery and Biochemistry Department of Surgery, East Carolina University School of Medicine, Greenville, North Carolina, USA

Severe obesity is a grave disease in the U.S. as well as other industrialized nations. This disease has many ramifications on both an individual and social levels. It affects 12.5 million people in the U.S., according to national survey data. The health risks of severe obesity include hypertension, hyperlipidaemia, cardiomyopathy, diabetes, hypoventilation disorders, increased risk of malignancy, cholelithiasis, degenerative arthritis, infertility, and psychosocial impairments. Medical weight reduction programmes have rarely achieved long-term success. Most authorities now agree that bariatric surgery is the treatment of choice for well-informed and motivated obese patients with acceptable operative risks, who strongly desire substantial weight loss or who have severe impairments because of their weight. Surgery is indicated for patients with a BMI greater than 40 kg/m2, or for those with serious medical co-morbidities and a BMI greater than 35 kg/m2. Three procedures, the adjustable silicone gastric banding (ASGB), vertical gastric banding (VBG), and gastric bypass (GB), have produced the best results to date. Each of these procedures is much more effective than dietary therapies. Each has advantages and disadvantages, with GB producing greater sustained weight loss in the long-term, with a slightly higher risk of metabolic complications. All can be done with surprisingly low operative mortality. The pronounced weight loss induced with these operations can relieve and bring co-morbid diseases, such as diabetes and hypertension, once thought to be only barely controllable, into full long-term remission. Key words: morbid obesity; bariatric surgery; diabetes; gastric bypass; gastroplasty; banding.

For the very overweight, surgery is the only approach that has proved to provide effective, safe and durable weight control. Severe obesity is a grave disease in the USA as well as other industrialized nations. This disease has many ramifications on both an individual and a social level. According to national survey data it affects 12.5 million people in the USA.1 Approximately 4 million people can be considered severely obese in that the their weight poses a major health risk to themselves. Previous studies have clearly documented that there is increased morbidity and mortality in this group.2,3 The health risks of severe obesity include hypertension, hyperlipidaemia, cardiomyopathy, diabetes, hypoventilation disorders, an increased risk of malignancy, cholelithiasis, degenerative arthritis, infertility and psychosocial impairments. Obesity is also expensive. Health care costs of $45.8 billion, or 6.8% of health-care expenditures in 1990, are attributed to the treatment of the disease.4 Add to this the cost of treating * Corresponding author. 1521–690X/99/010149 + 24 $12.00/00

© 1999, Baillière Tindall

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co-morbidities of obesity, such as cardiovascular disease and diabetes, and estimates climbed to almost $70 billion in 1990.5 Medical weight reduction programmes, incorporating dieting, exercise and behavioural modification alone or in combination, have rarely achieved long-term success: almost all participants tend to return to their original weights at 5 years. Unfortunately, the modest weight loss of 10 kg reported at 10 years by one of the more successful behavioural studies6 is not enough successfully to treat the severely obese. The severely obese appear to eat little more than non-obese individuals per unit of lean body mass.7 In addition, those who were previously obese seem to require fewer calories for weight maintenance than do those who have never been obese. Sugerman and associates7 explain these failures in weight control with the observation that obese individuals have an enhanced ‘metabolic efficiency’, with low metabolic rates and constant energy expenditure levels. In 1991, the National Institutes of Health Consensus Conference addressed nonsurgical and surgical treatments for severe obesity, as well as patient selection, the risks of surgery and the need for future research and epidemiological evaluation of these therapies.8 Most authorities now agree with their statement that bariatric surgery is the treatment of choice for well-informed and motivated obese patients with acceptable operative risks who strongly desire substantial weight loss or who have severe impairments because of their weight. The Conference concluded that surgery was indicated for patients with a body mass index (BMI) 40 kg/m2, or for those with serious medical comorbidities and a BMI over ≥35 kg/m2. DEFINITION OF OBESITY Obesity was traditionally defined on the basis of the ideal body weight (IBW) as defined by the mid-ranges for each height in the Metropolitan Life Insurance Tables. Obesity was defined at 125% of IBW and morbid obesity at 200% of IBW, or 100 lb (45 kg) over the IBW. These tables, however, proved to be insufficient for predicting the severity of obesity because of the arbitrary definition of body frame sizes and the lack of consideration of lean tissue mass. Accordingly, most bariatric surgeons have adopted George Bray’s standard, the body mass index (BMI = kg/m2), as a reasonably reliable indicator of excess fat. A BMI of over 30 kg/m2, is an indicator of obesity, one of over 40 kg/m2 defining severe, or class IV, obesity.9 Patients who are 225% of IBW with a BMI of over 50 kg/m2 are considered to be super-obese. The measure, however, is limited by its inability to differentiate between muscle and fat. For example, one of our university’s football players weighed 308 Ib (140 kg) at a height of 5 feet 8 inches (1.72 m) which give, a BMI of 47 kg/m2, yet hydroimmersion indicated that fat accounted for only 7% of his body composition. Surgeons need to be aware of this limitation because requests for bariatric surgery from police officers or members of the military who exceed the weight standards of their forces are not uncommon. It is wise, in such cases, also to evaluate the patients with another indicator of fat mass, for example hydroimmersion, to avoid performing surgery on a healthy, well-muscled man. Even so, for most individuals, the BMI is an enormously useful index because height and weight are objective, inexpensive and readily obtainable in even the simplest clinical setting. HISTORICAL ASPECTS The progression of bariatric surgery is interesting for its historical value and is useful as a record of physiological studies of the intestine in man. Over 30 surgical procedures

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have been described for the treatment of severe obesity. Comparisons of various procedures have been quite difficult to make as reporting methods have varied widely and follow-up has often been short. The early versions were associated with significant complications, in both the peri-operative period and the long term. Furthermore there was no clear consensus on the definition of severe obesity and the indications for surgery. Jejunoileal bypass Kremen et al10 were the first to recognize that severe obesity was such a serious disease that even surgery should be considered as an option. In 1954, after performing a study in dogs, they reported a patient in whom weight loss was achieved after endto-end jejunoileostomy. The first bariatric surgery clinical series was performed by Payne and DeWind in 1956.11 Their operation consisted of an end-to-side anastomosis of the proximal 36 cm of jejunum to the mid-transverse colon. The procedure produced dramatic weight loss, but cirrhosis, electrolyte imbalance and liver failure were significant complications. In three of their patients, end-to-side jejunoileostomies were performed using 14 inches (35.6 cm) of jejunum distal to the ligament of Treitz, anastomosed to the final 4 inches (10.1 cm) of ileum. By 1967, Payne and DeWind recommended against jejunocolic bypass and performed only jejunoileostomies. With end-to-side jejunoileostomy, an unpredictable amount of backwash occurred up the bypassed segment of ileum. Because this had a tendency to increase the absorptive area of intestine, further modifications to jejunoileal bypass were made by Scott et al12 and Buchwald et al.13 They evaluated end-to-end jejunoileostomies with varying lengths of intestinal limbs and finally determined that the ‘14/4 bypass’, i.e., 14 inches (35.6 cm) of jejunum joined directly into the terminal 4 inches (10.1 cm) of ileum (about a total of 46 cm of total small bowel length) provided an effective bariatric operation (Figure 1). The bypassed limb of ileum was drained into the colon. In terms of weight control, results were good in 80% of jejunoileal bypasses, with an average weight loss of 45 kg. Long-term results of bypasses conducted with more than 25 inches (63.5 cm) of combined intestinal channel were unsatisfactory, with most patients regaining their lost weight.

Figure 1. Intestinal bypass. Even the most successful version with 14 inches (35.6 cm) of proximal jejunum joined end-to-end with 4 inches (10.1 cm) of ileum produced only variable weight loss with an unacceptably high metabolic complication rate.

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Even at the optimal length, however, the intestinal bypasses produced disappointing and dangerous results. Twenty per cent of patients failed to lose enough weight, over half of the patients required re-hospitalization, and many required reversal of their bypasses to prevent liver failure. High complication rates were common, and there were often severe metabolic derangements, such as hypocalcaemia, hypokalaemia and hypomagnesaemia. Iron, zinc, vitamin B12, and folate deficiencies were frequently seen, and protein-calorie malnutrition was common. Severe diarrhoea compounded the mineral and electrolyte deficiencies. Bacterial overgrowth in the bypassed limb led to further problems. These consisted of bypass enteritis with occasional pneumatosis intestinalis, interstitial nephritis, vitamin K deficiency and renal failure. Finally, severe complications appeared in 20% of the patients, one in every five, who presented with such serious problems as nephrolithiasis, liver failure, autoimmune arthritis and advanced osteoporosis. Decreased free calcium entering the colon led to increased oxalate absorption and hyperoxaluria, which precipitated the stones. Liver abnormalities (steatosis and hepatitis) already exist in many of the severely obese14, and these changes may contribute to the risk of developing cirrhosis after jejunoileal bypass. O’Leary15 demonstrated that these problems could appear long (more than 10 years) after the procedure, even years after apparent good health. Gastric bypass The failure of the intestinal bypasses soon led to a search for more effective and safer procedures. The most promising of these was the gastric bypass, developed in 1966 by Mason and Ito16 after observing significant weight loss in patients who had undergone high partial gastrectomy for ulcer disease. Their original operation delineated the three elements of the operation: (1) a small gastric reservoir to limit intake, (2) a gastrojejunostomy to limit gastric emptying, and (3) a bypass of the stomach and duodenum to interfere with absorption and digestion. Even so, the first version, shown in Figure 2, had a number of problems. The proximal gastric pouch was too large, the anastomosis was too wide at 2–3 cm, the single staple line used to partition the stomach had a high failure rate, and the loop gastroenterostomy produced biliary reflux. A number of versions followed as the requirements for a successful gastric bypass gradually became apparent. Since 1980, we have been pleased with our modification, the Greenville Gastric Bypass (Figure 3), which has the following characteristics: 1. a gastric pouch of 20–30 ml; 2. a gastric partition created with three superimposed layers of staples applied with the TA-90 stapling device; 3. a gastroenterostomy of 8–10 mm; 4. a Roux-en-Y loop of jejunum of 40–60 cm in length. Partitioning of the stomach has gone through significant changes because of early problems with failure of the staple lines. Single staple lines (a double row of staples produced by one application of the TA-90 stapler) failed almost universally. Double staple lines (four rows of staples) have a failure rate of 20%, some ruptures occurring as late as 10 years after surgery. The triple superimposed application of a single TA-90 developed by Sugerman et al seems to have the lowest failure rate (1–2%).22 Surprisingly, division of the distal stomach from the pouch has not proved to be a better procedure. Not only is it technically more challenging; but it is also associated with a 6% failure rate because of the formation of gastro-gastric fistulae.

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Figure 2. Original gastric bypass. This procedure, introduced by Mason and Ito16, was a major breakthrough as a concept. Later versions, however, demonstrated that the operation could be improved with a smaller gastric pouch, a more limiting anastomosis and a stronger partitioning staple line. Furthermore, the loop gastroenterostomy produced a reflux of bile and pancreatic juice into the oesophagus.

Figure 3. Greenville gastric bypass. This commonly performed version of the gastric bypass limits intake through a 20–30 ml proximal gastric pouch, delays gastric emptying with an 8–10 mm gastroenterostomy and interferes with digestion and absorption by bypassing the antrum, duodenum and 40–60 cm of proximal jejunum. The operation produces a predictable and durable weight loss with low morbidity and mortality rates.

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One of the disappointments of the gastric bypass is that patients generally do not reach their ideal body weight. Almost all are cured of their severe obesity, but the great majority remain overweight, levelling out at about 10–30% above their desired weight. Even though the reduction in weight of a patient from 400 lb (182 kg) to 240 lb (109 kg), maintained for over a decade, is a remarkable accomplishment, many gastric bypass patients still seek to achieve normal weights. Accordingly, in a search for an even more effective bariatric procedure, modifications of the gastric bypass incorporating longer biliopancreatic afferent limbs (and thus shorter intestinal common channels) have been devised that exaggerate the malabsorptive effects of the gastric bypass. The first of these was described by Scopinaro et al17 and is termed biliopancreatic diversion (BPD). Superior weight loss is achieved with BPD, but the incidence of protein-calorie malnutrition is higher, as is the operative mortality. These distal gastric bypasses may be useful in obtaining better weight loss in the super-obese (BMI >50 kg/m2) or as a salvage procedure for those who fail other procedures. Gastroplasty Gastroplasty, i.e. a restrictive procedure without a bypass of the gut, was developed as another method of restricting the amount of food allowed into the intestine following a meal. The early forms of gastroplasty were horizontal, the stomach being partitioned into a small proximal pouch and a larger distal compartment. Drainage was accomplished by either removing staples from the middle of the cartridge or by forming a channel on the greater curvature. Most of these procedures failed to achieve stable and prolonged weight loss because either the stoma would dilate or the staple line would disrupt. In 1980, Mason18 developed the vertical banded gastroplasty (VBG) as an alternative to gastric bypass (Figure 4). The weight loss following this operation tends to be 10–15%

Figure 4. Vertical banded gastroplasty. This operation differs from the bypass in that it limits intake and the rate of gastric emptying; it does not interfere with digestion and absorption. It was a popular procedure until experience demonstrated that it produced less weight loss than gastric bypass and that the plastic mesh band could lead to obstructions and perforations of the stomach.

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less than that attainable with gastric bypass, but VBG patients are much less likely to experience the vitamin deficiencies that frequently follow the gastric bypass. Further more, the VBG patients do not develop symptoms of dumping syndrome or marginal ulcers as do bypass patients, and are thus less likely to develop maladaptive eating patterns. Unfortunately, the VBG has its own set of complications, including obstruction of the gastric outlet as a result of occlusion by food or tipping of the rigid band. In addition, weight loss is often inadequate because of the ingestion of sweets or ‘soft calories’. Post-operative weight loss after VBG becomes problematic with these ‘sweet-eaters’ who consume high-calorie, sweet liquids, often because they are less likely than gastric bypass patients to return to a ‘normal’ diet because of difficulties with the band. Although there has been one study with results that appear to refute the practice of selecting ‘sweet eaters’ for VBG over gastric bypass15, many authorities now believe that some VBG patients (approximately 10%) have a tendency to develop a propensity for sweets.20,21 When identified pre-operatively as ‘sweet-eaters’, patients should be selected for gastric bypass procedures as their dumping symptoms will help to curb their intake of high-calorie liquids. However, it must be recognized that about 15% of gastric bypass patients will not develop dumping syndrome symptoms or will lose them in 2–3 years. Both gastric bypass and VBG can fail when patients consume frequent, small, high-fat or high-carbohydrate snacks.22 Opinion is still divided on whether or not to perform VBG for non-sweet eaters. Although hard data are lacking, it is our opinion that bariatric surgeons are performing fewer VBG procedures and, in increasing proportion, more gastric bypasses. Gastric banding The concept of gastric banding began in 1976 with Wilkinson.23 He originally used a piece of Marlex mesh to shape the stomach into an hourglass configuration, later modifying this to wrapping the entire stomach. Molina24 next explored gastric banding by creating small nylon, followed by Dacron, bands placed through small skin incisions. Neither of these procedures had good long-term results. In 1989, Kuzmak25 introduced adjustable silicone gastric banding (ASGB). ASGB employs of a dacron-reinforced silicone band that contains an inflatable section (Figure 5). A non-kinking tube leading to a self-sealing subcutaneous reservoir containing saline connects this section. An electronic sensor is used to help to adjust the

Figure 5. Adjustable gastric banding. This gastroplasty forms a small gastric pouch with an adjustable belt that can be made larger or smaller by altering the amount of water in a connecting, subcutaneous reservoir. The operation has the advantages that it can be carried out laparoscopically and is easily reversed. The reported experience is mixed but appears promising if the problems with the band can be resolved.

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stoma diameter precisely. Most recently, this procedure is being performed laparoscopically26 in an attempt to lower post-operative morbidity. One European series reported similar results in weight loss between laparoscopic ASGB (LASGB) and VBG.27 LASGB is currently undergoing Phase III Food and Drug Administration (FDA) trials in the US and is not yet available on the market. Our programme in Greenville, North Carolina, is one of four national testing centres. The study is now closed, and preliminary results are pending. Other procedures Jaw wiring Jaw wiring is based on the observation that patients with broken jaws generally lose weight as a result of the limitation of their diets to liquid foods. The procedure has yielded disappointing results. Although patients generally lose weight if kept wired, they tend to regain weight as soon as the wires are removed, even if a major change in their appearance is evident.28 Further, many severely obese patients are edentulous and, because of their emotional problems, tend to demand removal of the wires within a few days. With the development of safe and effective surgical procedures for weight loss, jaw wiring has become a procedure of historical interest alone. Balloons and wraps Garren introduced the gastric balloon in 1984.29 This device was designed to cause early satiety by acting as an artificial bezoar. The gastric balloon did not result in significantly more weight loss than diet and behavioural modification alone. A high complication rate involving obstruction, ulceration and perforation was associated with the device.30 The FDA removed it from the market. Total gastric wraps have also fallen into disfavour because of the high incidence of foreign body erosions.

MANAGEMENT Patient selection Bariatric surgery is a major undertaking. Most surgeons and insurance carriers have generally adopted the following indications: 1. age 16–65 years; 2. a BMI ≥40 kg/m2; 3. a BMI ≥35 kg/m2 if the patient has co-morbidities such as diabetes, sleep apnoea, limiting arthritis, cardiac failure, obstructive pulmonary disease, endocrine disorders, pseudotumour cerebri and stress incontinence; 4. the patient is assessed to be an acceptable operative risk; 5. there is no evidence of alcohol or substance abuse; 6. there is informed consent with extra emphasis that the patient truly understands the procedure and the expected changes in lifestyle. Contra-indications include: 1. an unstable personality or uncontrolled addiction to alcohol or drugs;

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a history of serious depression or suicide attempts; age under 16 or over 65 years; a strong resistance in the family to the operation; unrealistic expectations of the surgery; inadequate intelligence to understand the operation and its long-term effects; a prediction that the patient will not comply with the requirement to supplement vitamin and mineral intake or undergo rigorous follow-up.

These points, however, are merely guidelines. We have performed successful bariatric surgery in a youthful woman of 67, and have had good results in patients with previous substance abuse problems when psychological consultation revealed that the problem was now under control. If a patient is a young and brittle diabetic but has not yet attained a BMI of over 35 kg/m2, surgery may be the best and least expensive choice. Furthermore, resistance to the operation by the family is common, but it can almost always be overcome with education and compassionate meetings with the relatives. Some patients need intensive evaluation before the decision to recommend surgery can be made. These individuals, who represent perhaps 10% of our patient population, may require admission to an intensive care unit to control their cardiac or pulmonary failure, prolonged psychotherapy or dermatological consultation to clean up their skin. Pre-operative evaluation The pre-operative evaluation should not be rushed. Unless the patient is critically ill, it is worthwhile to spend 2–3 months to ensure that the patient and family are well educated on the operation and its consequences. At the first visit, the patient is screened with an intensive interview, including a psychological screening questionnaire and a rigorous physical examination to determine whether the patient is a suitable candidate. A general discussion of severe obesity and an explanation of the operation and its consequences are presented. Educational materials are distributed. If the patient is deemed suitable at the end of the session, a complete blood count, blood chemistry panel (SMA-17), thyroid-stimulating hormone level, urinalysis and pregnancy test (if appropriate) are routinely ordered. If the psychological screening test suggests that further exploration is needed, a consultation is arranged with a project psychologist. Similarly, additional consultations are made to evaluate and stabilize any serious co-morbidities, such as heart failure, or sleep apnoea, if needed. The patient is next seen when the results from the various tests and consultations are available. At this time, if the patient is deemed a suitable candidate, the operation and its consequences are reviewed again, and the decision to proceed with surgery is reaffirmed. The request for insurance approval is then initiated. If the procedure is approved, the operation is scheduled. If the carrier does not reply affirmatively, the decision is challenged. The carrier usually requests additional information and then grants the request; refusals are uncommon now that severe obesity has been designated a disease covered by the Americans for Disability Act. The third visit is scheduled in the week prior to surgery to meet the requirements for the pre-operative work-up of the institution. At that time, the procedure, risks, alternatives and benefits of the proposed operation are reviewed again. The patient is generally admitted on the morning before surgery. Complicated cases, however, such as patients with severe cardiorespiratory failure, may need to be

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admitted as much as a week or two earlier to be brought to optimal pre-operative status. About 5% of our patients require placement of a Swan–Ganz catheter. A cephalosporin is given prophylactically on the morning of surgery and continued for 48 hours post-operatively. Intubation may be difficult, on occasion requiring placement of the tube under local anaesthesia. A nasogastric tube is placed early during the operation to ensure that the stomach is empty and to guide the dissection of the cardia. The operations are technically demanding, but experienced bariatric surgeons can generally carry out the procedures in 60–90 minutes. Blood loss is rarely a serious problem, and transfusions are seldom required. Care is required during the initial dissection to avoid injury to the spleen, perforation of the oesophagus, and injury to the bowel during the dissection of adhesions. Anastomoses, whether stapled or hand sewn, need to be tested for leaks using either methylene blue or air. At the end of the procedures, the abdomen should be irrigated well to remove clots and contaminated fluids. Closure of the abdomen must be secured with strong broad bites of fascia to minimize dehiscences and hernias, as the tissues of these patient do not have the tensile strength of their thinner counterparts. Drains in the subcutaneous tissues, although frequently used in the past, probably cause more infections than they prevent; we no longer use them. Bariatric surgery requires a well-trained team, of which the surgeon is only one component. Hospital staff must be taught that morbid obesity is a serious and treatable disease. Compassion and understanding are essential and must be stressed. Care paths that delineate routine orders and the expected progression can prevent errors and facilitate efficient recovery. Social services, psychological support, medical consultants experienced in bariatric medicine, and accomplished anaesthesiologists are the key ingredients for a strong programme. Finally, special equipment must be present in the hospital and the outpatient setting for the obese surgical patient. Strong and roomy examining tables, seats, wheelchairs, beds, gurneys and radiology apparatus are required for these patients, who may weigh well over 600 lb (272 kg). Post-operative care Post-operative care is critical because these patients have diminished resistance and multiple co-morbidities, and often do not manifest the classic signs of inflammation. The first 24 hours are particularly critical because of the possibility of a leak or intraabdominal infection. Persistent tachycardia over 120 beats per minute, fever over 39°C or the appearance of worsening illness despite normal vital signs mandates a limited upper gastrointestinal study to assist in the detection of an anastomotic leak. If this study is positive, or negative with the continuing clinical suspicion of a leak, it is generally best to proceed with emergency surgery. A negative exploration is considerably safer than a perforation that is missed. At our institution, patients typically spend the first night on an intermediate surgical unit with nurses who are familiar with bariatric care. A limited upper gastrointestinal study is performed on the second or third day. If this study shows no anastomotic leak, the patient is started on oral intake. A dietary regimen is typically started on the 4th day with 30 cm3 half-strength Ensure Plus four times daily and 30 cm3 of water per hour. This is advanced to fullstrength Ensure Plus with water at the same doses on the 5th or 6th day when patients are sent home. Before discharge, the dietitian again reviews with patients the specific dietary regimen to which they must adhere at home This includes full-strength Ensure and full liquids (instead of water) at the same dosage

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for 2 weeks. During the 2–6 weeks after surgery, patients are advanced cautiously to a full diet. Most patients change the quality of their diets as well as the quantity, with a reduction in sweets to a broader, more balanced diet. Many report the ability to eat half a hamburger, some french fries and a small glass of a diet soft drink at one meal after about 6 months. Even so, it is wise to remind these patients not to overeat, especially during the first 2 months when healing is still not complete. Long-term follow-up Patients generally do quite well. A daily long-term intake of vitamins and minerals is essential. After gastric bypass, vitamin B12 should be given at 600 µg per day. Vitamin deficiencies can produce serious problems. Wernicke-Korsakoff syndromes with permanent serious neuropathies have been reported when vitamin intake is not maintained. A weight gain exceeding 12% of the lowest post-operative weight is generally the result of staple line breakdown, pouch or anastomotic dilatation, or compulsive snacking. Abdominal pain is most commonly caused by cholecystitis, although it may occasionally be due to marginal ulcers near the anastomosis. These ulcers clear quickly with H2-blockers. Recurrent emesis usually signals overeating but may be the result of stenosis of a gastrojejunostomy limb. These strictures may be easily amenable to dilatation. A few patients may develop small bowel obstructions from intestinal adhesions; these generally clear on their own, but patients must be kept on nil by mouth, be hydrated and be kept under close observation. About a quarter of the patients report depressive episodes (about the same as before surgery) so continuing emotional support with surgery visits, support groups and consultations may be required depending on the severity of the depression. SURGICAL TECHNIQUES AND RESULTS Two procedures have persisted as being the most effective and safest approaches for the surgical treatment of severe obesity: the vertical banded gastroplasty and Rouxen-Y gastric bypass. Gastric banding remains a promising and increasingly used approach. The biliopancreatic diversion, or Scopinaro modification of gastric bypass, is occasionally used for the super-obese but more often as a salvage procedure for those who have failed less-demanding procedures. These treatments are classified into those that restrict the oral intake of food per meal and those that induce some type of malabsorptive effect. Restrictive procedures Gastric banding Gastric banding limits caloric intake by restricting the size of the reservoir. Most recently, the most successful approach to banding appears to be adjustable silicone gastric banding, proposed by Kuzmak.31 This procedure is performed either open or laparoscopically (Europe). The open technique is carried out through an upper midline incision. At 10 cm below the costal margin, the right rectus sheath is cut transversely, and part of the rectus muscle is transected to create a space for the reservoir. The abdomen is then entered in the midline. The hepatogastric ligament is opened, and a tunnel is formed by blunt dissection behind the stomach and around the fundus of the stomach. A Penrose drain

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is placed around the stomach for traction, and the fundus is further mobilized. A small opening is made at the lesser curvature 3 cm below the oesophagogastric junction and medial to the vessels and branches of the vagus nerve. The 1 cm wide soft silicone band is threaded through the opening around the stomach and connected to the reservoir. Calibrating tubing is inserted by the anaesthesiologist into the stomach, and the pouch is calibrated by inflating the balloon with 20 cm3 saline. The silicone band is then tightened with a buckle, and an electronic sensor is used to determine the size of the stoma. After adequate adjustment, the band is sutured to the stomach, and the redundant band material and buckle are excised. The mobilized greater curvature is then sutured with three or four 3–0 silk sutures over the band to the pouch. Results with ASGB have been good. In Kuzmak’s 7-year experience with 138 ASGB patients, he reported an average excess weight loss of 42.1 ± 25.5% at 1 year, 60.1 ± 27.3% at 2 years, 72.0 ± 26.5% at 3 years, and 76.0 ± 22.8% at 4 years. Longterm data, however, suggest that there is a tendency for some late weight regain.3 Gastroplasty The VBG developed by Mason is another procedure designed to restrict caloric intake by limited gastric reservoir size. It is performed using a midline abdominal incision. A 32 Fr gauge Ewald tube is passed into the stomach and positioned against the lesser curvature. A Penrose drain is then passed around the oesophagus above the cardia, and the gastrohepatic ligament is entered. The lesser sac in entered, and a passage is then made between the gastric neurovascular bundle and the gastric wall for the future collar. The Penrose drain is brought through, closely encompassing only oesophageal and gastric tissue, excluding the vessels and the branches of the vagus nerve. A 25 mm diameter end-to-end EEA stapler is used to create a window adjacent to the Ewald tube, positioned against the lesser curvature. The window may be reinforced with absorbable sutures if deemed necessary. A linear four-row stapler is applied through the gastric window parallel to the Ewald tube to produce the pouch. The final pouch volume is adjusted to 9–25 cm3, with an average of 15 cm3 as measured through the tube. The collar is created with a 1.5 × 7.0 cm strip of Marlex mesh marked and sewn to produce a 5 cm opening. At the end of the procedure, the integrity of the pouch is tested with insufflation of air with the abdomen filled with saline. The mesh is then covered with omentum. The abdomen is closed with absorbable suture, and the skin is stapled closed. Mason reported a 54% excess weight loss after 3 years in 45 patients after VBG. Similar results where reported by Dietel and associates, but again with only 3 years of follow-up.32 As with gastric banding, there appears to be a trend to late regain of weight with VBG after 2 years. In one study, only 40% of patients maintained the early weight loss after 9.6 years.33 A late, significant rise in body weight was seen in 60% of the patients, and, of these, one-half had returned almost to their pre-operative percentage over IBW. An excess ingestion of high-calorie liquid and semi-liquid foods was volunteered by many of these patients to account for their weight gain. Nevertheless, VBG continues to be a safe and effective operation for severe obesity. Further studies are needed to assess the late effectiveness of this procedure. Malabsorptive procedures Gastric bypass The initial gastric bypass described by Mason in 1962 has undergone continuous

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modification. Gastric bypass combines the restriction of oral intake by limiting the size of the gastric pouch, along with the malabsorptive effect of dumping syndrome and duodenal exclusion to effect significant and long-term weight loss. Additional malabsorptive effects can also be obtained by performing an ‘extended’ gastric bypass, with its longer afferent intestinal limb and shorter common channel. Dumping syndrome is a desired effect of the operation. The VBG fails in ‘sweeteaters’ who adapt to their restricted intake by snacking frequently on soft or liquid foods high in carbohydrates (sugar). Dumping syndrome averts this behaviour, as it is associated with unpleasant symptoms such as lightheadedness, sweating, palpitations, abdominal cramping and diarrhoea. Symptoms occur when the small intestine is exposed to an abnormally large sugar load over a short period of time. Dumping has been associated with a spike in enteroglucagon level that occurs 30 minutes after the ingestion of the glucose meal and correlates well with the onset of symptoms.34 Our Greenville modification of the gastric bypass uses a 20–30 cm3 proximal pouch that is connected to a standard 40–60 cm Roux-en-Y limb with an 8–10 mm double-layered gastroenterostomy. The biliopancreatic limb also measures 40–60 cm, depending on the mobility of the gut. (It should be noted that the measurements are given in actually measured ranges; the intestine does not lend itself to precision.) The operation is begun with a high midline incision, and an Omni retractor provides exposure. If there are no contra-indications upon exploration of the abdomen, the upper stomach is isolated by inserting a finger behind the oesophagus to the left of the gastro-osophageal junction and bluntly dissecting down to a point along the lesser curvature 2.5–3.0 cm below the gastrooesophageal junction. A number 36 Malecot catheter is used to pass a TA-90 stapler through the passage dissected. A proximal pouch measuring 4 cm in width and 1.5 cm in height is then formed with the stapler. Two additional staple loads are then superimposed over the first. A figure-of-eight suture is placed at each end of the staple line to close the ends securely and to serve as guy sutures. Next, the jejunum is divided 40–60 cm from the ligament of Treitz with a GIA stapler and then threaded through the mesocolon and the lesser sac (retrocolic) to the proximal greater curvature. The proximal end of the distal jejunum is then sutured to the gastric pouch. The anastomosis is sewn with continuous polypropylene suture in two layers to fit loosely around a 0.8 cm Salem sump tube. The Rouxen-Y enteroenterostomy is then completed by joining the proximal jejunum end to side with GIA and TA-55 staplers to the distal jejunum 60 cm below the gastroenterostomy. It is important to ensure that the intestine is not constricted in its passage through the lesser sac, that the Roux-en-Y loop is attached to the mesocolon with three sutures to prevent internal hernias, and that the enteroenterostomy is not bleeding from the internal staple line before applying the TA-55. The abdomen is closed with an absorbable suture, and the skin is stapled. Significant and durable weight loss is achieved with the Greenville gastric bypass. Long-term weight loss of 50% of excess weight can be expected. Data from a longterm study at our institution (Table 1) show that there is a significant weight drop during the first year, with a tendency to lose some additional weight at 18 months. At 2 years, an average maximum of 70% excess weight loss is achieved. At 5 years, mean weight loss is 58% of excess body weight; after 10 years, 55%; and after 14 years, 49%. At 16 years (not included in the table), weight loss continues to remain at about 50% of excess weight. This table is depicted in Figure 6.

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Table 1. Weight loss in 608 morbidly obese patients after the gastric bypass over 14 years with 97% follow-up. Mean weight (lb) (range) Pre-operation 1 year 5 years 10 years 14 years

304.4 192.2 205.4 206.2 204.7

(198–615) (104–466) (107–512) (130–388) (158–270)

% Excess weight loss (range) 0.0 68.9 (10.3–124) −57.7 (−14.6–115.9) − 54.7 (−0.9–103.1) − 49.2 (7.2–80.9)

Body mass index 49.7 31.5 33.7 34.7 34.9

(33.9–101.6) (19.1–69.3) (19.6–7.16) (22.5–64.7) (25.9–54.6)

Biliopancreatic diversion The BPD bypass represents a combination of the gastric bypass and the intestinal bypass. It produces greater weight loss than achievable with Roux-en-Y gastric alone bypass but is associated with more complications. A distal gastrectomy is performed, which results in a 200 cm3 gastric pouch. The ileum is divided 250 cm proximal to the ileocaecal valve. The distal end is then anastomosed to the gastric pouch, and the proximal end is anastomosed to the distal ileum 50 cm from the ileocecal valve in an end-to-side manner. This creates a short common channel that inhibits digestion and absorption. A cholecystectomy is also performed. Because of the gastrectomy, this operation is not reversible. According to an 18-year follow-up on BPD by Scopinaro et al, the procedure creates about a 75 ± 10% reduction in excess body weight, and this remains stable at 15 years with a mean loss of 70% of excess weight.35 Caution The safety of these operations depends on secure anastomoses, whether hand sewn or stapled, and on viable intestine. It is therefore essential that the integrity of every gastroenterostomy be tested during surgery with methylene blue or air. Intestinal loops must also be checked for viability and blood supply. If the colour of the gut is in question, blood flow must be assured or the operation re-done. COMPARISONS Several prospective studies have been published comparing gastroplasty with gastric bypass. In each study, the gastric bypass proved to be the more effective procedure, usually with only a slightly higher risk of complication. Defining success as a weight loss of more than 50% of excess weight, the Adelaide study demonstrated that, at 3 years, the success rate for gastrogastrostomy was 17%; for VBG, 48%; and for Roux-en-Y gastric bypass, 67%.36 A study by Capella and Capella37 also revealed that gastric bypass achieved superior results, the VBG group losing 45% of their excess weight compared with 60% for Roux-en-Y gastric bypass at 5 years. This study used a lesser curvature pouch, which had a high incidence of staple line disruption (22%). Sugerman and associates found that gastric bypass was superior to VBG even when ‘sweet-eaters’ were pre-operatively assigned to gastric bypass and non-‘sweet eaters’ to VBG.22 With the ‘sweet-eaters’ excluded, gastric bypass still produces 10–15% more excess weight loss than VBG.

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The gastric bypass is also superior to other forms of gastroplasty, such as ASGB. Long-term weight loss tends to be 10–15% less than procedures that include a malabsorptive component. However, the advantage with these procedures, as well as with VBG, is that they are reversible, with a slightly lower complication rate. Belachew and Monami27 reported that weight loss between open and laparoscopic ASGB was equivalent to that with VBG.

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As discussed earlier, the BPD produces vastly superior weight reduction compared with the other treatment options, with a mean excess weight loss of over 70% at 15 years. However, these results are obtained at the expense of a 40–50% incidence of metabolic complications. Moreover, BPD is not reversible. The current attitude toward this procedure is that it should be used rarely and under rigid indications. In summary, all three procedures (ASGB, VBG and gastric bypass) have been shown to be effective therapies for severe obesity. Each of these procedures is much more effective than dietary therapies. All can be done with a surprisingly low operative mortality (even though many patients present with cardiopulmonary failure and diabetes) lower than 1% for good-risk patients and fewer than 2% for patients with severe co-morbidities. EFFECTS ON CO-MORBIDITIES Cardiovascular Numerous studies have shown that effective weight loss is associated with a correction of cardiac dysfunction and a fall in blood pressure in patients with severe obesity.38 The maximal fall in blood pressure has been shown to occur well before normal weight is achieved39, perhaps because of the decrease in total blood volume. A study performed by Foley et al40 revealed that the typical weight reduction seen in gastric bypass surgery can provide control of hypertension, even though the final weight achieved may be well in excess of the IBW. In this study, 26% of 289 patients were considered hypertensive, and hypertension resolved in 66% of these after surgery. Weight loss favourably affects cardiac structure and function as well Left ventricular (LV) wall and interventricular septum thickness reduce in size, LV stroke work index improves, and right heart catheterization shows decreased cardiac output and an improved response to exercise.41 Backman et al42 reported on haemodynamics obtained before and after a jejunoileostomy-induced 58.1 kg weight loss, from 104% to 39% over IBW in 22 extremely obese patients. Weight loss was associated with decreases in maximal oxygen consumption, cardiac output, stroke volume and mean blood pressure. There was no change in systemic vascular resistance of LV end-diastolic pressure. In a study of 29 severely obese patients, Alpert et al43 show that, in patients with preoperative decreased LV fractional shortening, substantial weight loss improved LV fractional shortening. This was accompanied by decreased systolic blood pressure, LV internal dimensions in diastole and systole, LV end-diastolic stress and LV mass. Lipid abnormalities also improve post-operatively. Gleysteen44 has shown that, in both sexes, marked reductions in the ratios of total cholesterol to high-density lipoprotein (HDL)-C are attained, and this is sustained over 5–7 years. Weight reduction has not been shown to directly affect the risk of developing coronary heart disease, but, by modification of several of the risk factors (hypertension, diabetes and lipid profile), it is probable that this is achieved. Data from the ongoing Swedish Obese Subjects study should help to clarify this issue. Pulmonary Obstructive sleep apnoea and obesity hypoventilation syndromes are both associated with high mortality rates and serious morbidity; effective weight reduction can correct both. Sugerman and associates followed 38 patients with obesity hypoventilation for

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almost 6 years after gastric surgery.62 There were significant increases in PaO2 and decreases in PaCO2 in these patients. Of 57 patients with sleep apnoea available for follow-up, 38 (or two-thirds) were completely asymptomatic at an average of 3.2 years post-operatively. In another study of 47 patients, sleep apnoea disappeared in 40% of patients, with marked reduction of apnoea in 72%.45 Respiratory insufficiency returns if weight is regained. Loss of weight from gastric banding has been shown to improve lung volumes and dynamic function, and reduce ventilation/perfusion disturbances.46 A combination of a marked reduction in ventilatory demands and a moderate rise in ventilatory capacity leads to this beneficial effect. Respiratory muscle endurance improves with significant weight loss.47 Endocrine Surgery for severe obesity has proved to be the most effective treatment of type II diabetes associated with obesity, with an 83% cure rate after 14 years. One group has studied the effects of normalizing weight on impaired insulin metabolism in severely obese women undergoing VBG.48 In this study, non-diabetic obese women were matched with non-obese healthy controls. After a follow-up of approximately 14 months, the obese women achieved normalization of their weight to 1BW, with essentially similar BMIs to those of the controls. Normalization of their weight resulted in a complete correction of insulin secretion, insulin clearance and insulin sensitivity. Additionally, it was clear that improvements in insulin metabolism appeared well before the recovery of ideal body weight. In three previous studies from our institution, the control of type II diabetes with gastric bypass surgery was well documented. In the first study of Roux-en-Y gastric bypass effects on diabetes, we were able to show, with a 14-year follow-up (97% of patients being followed), that 121 out of 146 (82.9%) diabetic severely obese patients reverted to and maintained normal Hgb-A1c, plasma insulin and plasma glucose levels (Figure 7). In 150 out of 152 (99%) severely obese patients with impaired glucose tolerance, a normalization of glucose and insulin metabolism was also observed.49 A second study demonstrated that gastric bypass also prevents pre-diabetic patients progressing to frank type II diabetes mellitus. In that investigation, 55 severely obese glucose-intolerant subjects undergoing gastric bypass were compared with a matched group of 11 severely obese glucose intolerant subjects not undergoing surgery. After 8 years of follow-up in the non-surgical group and 10 years for those in the surgical arm, six out of 11 (55%) patients in the control group developed type II diabetes compared with none out of the 55 who underwent gastric bypass surgery.50 The third study showed that these improvements in diabetic indices were not merely academic but resulted in better survival. We compared, over 15 years, 154 severely obese patients with type II diabetes having Roux-en-Y gastric bypass with 78 matched patients with type II diabetes who did not have surgery. Initially, 56.4% of the nonsurgical group required medical management of their diabetes, increasing to 87.5% at last contact. In contrast, the percentage of surgical patients requiring medical management of their diabetes fell from 31.8% to 8.6% after gastric bypass. The mortality in the nonsurgical group was 28%, or 4.5% per year, versus 9%, or 1% per year, in the surgical group (including peri-operative deaths). We were also able to show that the earlier that patients undergo gastric bypass (within 2 years of the diagnosis of diabetes), the greater the likelihood of complete resolution of their diabetes. To our knowledge, gastric bypass is the only therapy ever reported to reduce the mortality from type II diabetes mellitus.

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Weight loss is not the critical factor contributing to the improvement in insulin and glucose metabolism after gastric bypass. As discussed in our latest study51 a return to euglycaemia and normal insulin levels occurs within days of the operation, before any significant weight loss is achieved (Figure 8). Even a 5% weight loss induced from a dietary programme is often sufficient to produce marked reductions of plasma glucose and insulin resistance, even though the patient is still obese. Thus the restoration of normal glucose and insulin metabolism must be caused by either reduced calorie intake

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or exclusion of the foregut (antrum, duodenum and proximal jejunum). The latter mechanism may have a more important role in the correction of type II diabetes than previously believed, although both controls are probably involved. In a previous comparison of VBG and GB by Kellum et al52 although significant weight losses were achieved in both groups, the VBG group had smaller reductions in hyperglycaemia and hyperinsulinaemia than did the gastric bypass group. This again suggests that bypassing the foregut, rather than simply decreasing calorie intake, has an important role in correcting type II diabetes. It seems reasonable to conclude then that the foregut has an important role to play in the development of type II diabetes. This might be mediated in susceptible persons through an overstimulation of the islet cells by gut hormones such as incretins (glucagon, glucagon-like peptide and glucose-dependent insulinotropic polypeptide). Psychosocial Kral et al53 assessed changes in quality of life of severely obese patients before and after gastric surgery. They found that patients with significant weight loss demonstrated dramatic improvements in their quality of life. Quality of life was measured in subjective terms such as self-assessments, as well as the presence or absence of psychological symptoms. Objective measurements, such as econometric ones, also showed an improvement, as in the Adelaide study.54 In addition to showing that selfimage and state of happiness improved with gastric surgery patients, there was an increase in full-time or part-time employment from 38% before surgery to 60% 3 years after surgery. A study by Larson also describes that weight reduction was instrumental in improving psychosocial functioning in the majority of their group of 90 patients undergoing gastroplasty.55 What was most interesting about this study was that a subgroup of patients (19%) was identified who had a negative psychosocial reaction despite sufficient weight loss. This group tended to seek psychiatric help preoperatively much more frequently than did the rest. Our own studies, however, suggest that the improvement in mental health indices is temporary, returning to preoperative levels within 3 years. COMPLICATIONS General In experienced centres, the mortality from bariatric surgery is usually 1.5% or less. The incidence of complications increases with the severity of patient co-morbiditly. The most common early complications include the intra-operative incidents, especially injury to the spleen, stapling the nasogastric tube into the anastomosis, incorrect anastomotic connections and injury to the oesophagus. During the early post-operative period, anastomotic leaks or infections in the left upper quadrant are the most feared complications. An indication of either of these events should trigger prompt exploratory laparotomy. Other early complications mirror those of abdominal general surgery, i.e. wound infections, dehiscence, ileus, cardiopulmonary failure, pulmonary embolus, pneumonia and myocardial infarction. Rapid post-operative weight loss is associated with a high rate of cholelithiasis in the form of cholesterol gallstones (10–50%). A multicentre, randomized, prospective trial has shown that the prophylactic use of ursodiol after gastric bypass can decrease

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the incidence of gallstone formation to 2%.56 This complication occurs in about 1% of cases. Incisional hernias occurred in 24% of 608 patients in our series after gastric bypass. The risk of hernia increases with pulmonary dysfunction or diabetes. It is usually best repaired 12–18 months postoperatively, after the rapid weight loss phase. In our series, 8.2% required hospital readmission, and 2.8% of patients required reoperation during the early post-operative period. Other general complications encountered in our gastric bypass study were vitamin B12 deficiency (40%), anaemia (39%), depression (23.4%), gastritis (13.2%), minor wound infection (8.7%), severe wound infection (3.0%), splenic tear (2.5%) and intra-abdominal abscess (2.5%). Gastric banding In Kuzmak’s series, the operative mortality was 0.7%. Stoma complications occurred in 8%, eight stomas requiring revision and two bands requiring replacement because of erosion. He reported no wound infections, dehiscences or intra-abdominal infections. Løvig et al57 have reported higher rates of band erosion (5.2%). A high incidence of partial gastric outlet obstruction (2.9%) with gastric perforation (1.7%) occurred. Incisional hernias occurred in 8.6% of patients. The reoperation rate was 7.5% and there was a tendency toward late regain of weight at 2 years.57 Gastroplasty Näslund et al reported a 14% reoperation rate, 10% being for ruptured staple lines and the remaining 4% for band erosions and outlet stenoses.58 MacLean et al reported a 48% staple line disruption in 201 patients after performing gastroscopy three times in the first year and obtaining upper gastrointestinal studies on all who gained weight with negative gastroscopy.59 Reoperation was required in 43% of patients, half of these being required for stomal stenosis. Oesophagitis and reflux have been reported in some cases of stomal stenosis. Weight can be regained through maladaptive eating behaviours. Finally, occasional band erosions (2–3%) can occur. Gastric bypass Staple line failure occurred in 15% of 608 patients undergoing Roux-en-Y gastric bypass in our series. The majority of these failures occurred before changing to the triple, superimposed staple line as proposed by Sugerman. Since then, our failure rate has been under 2% as determined by routine gastrointestinal series 6 months after surgery. Because a retrocolic limb is used, there is a risk of internal hernia as a complication. Furthermore, acute gastric distension may develop in the bypassed stomach, requiring emergent decompression. Other risks specific to gastric bypass are discussed below. Nutritional The most frequent nutritional deficiency is an insufficient intake of vitamins, iron and proteins, thus leading to anaemia. Anaemia is much less likely after gastroplasty, but iron deficiency may occur. Thiamine deficiency may also occur, especially if there is intractable vomiting.

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Nutritional deficiencies are much more frequent after gastric bypass than VBG because of duodenal exclusion. Iron and calcium are readily absorbed in the duodenum. Low vitamin B12 and B1 levels are readily observed as well. Patients should be supplemented post-operatively with these vitamins and minerals to avoid bone demineralization, anaemia, peripheral neuropathy and malnutrition. As noted earlier, Wernicke–Korsakoff neuropathies have been reported in patients who have not complied with the directions to maintain their vitamin supplementation. The most severe nutritional deficiencies are seen with BPD. Scopinaro observed protein-calorie malnutrition in only 12% of patients in Italy, but the experience in the USA with our national diets is much less favourable. Iron, calcium and vitamin deficiencies occur in 35% of BPD patients.59 Despite supplementation, 7% of BPD patients still develop bone demineralization between the second and fifth postoperative year. REVISIONAL SURGERY Of those patients undergoing VBG, up to 36% will require some type of revisional surgery; after gastric bypass, between 5% and 23% will come to a revision.60 Most failures in bariatric surgery are due to either disruption of the staple line, stenosis of the gastric outlet, distension of the pouch or dilated gastrojejunostomies. The usual indications for revision include inadequate weight loss, metabolic and nutritional complications, gastrointestinal side-effects in the setting of adequate weight loss, and technical failures. It has been shown that revisional surgery can be performed safely, although morbidity and mortality rates are somewhat higher than those reported for initial surgery. The incidence of revisional surgery for failed VBG in one Dutch study was 56% over a 12-year period.61 They were able to demonstrate that if a failed VBG was revised to another VBG, 68% of those cases would need revisional surgery over the following 5 years. In their series, no further revisional surgery was required if they converted to a gastric bypass, and satisfactory weight loss was still achieved. Failed VBGs are best converted to gastric bypass with a lesser curve pouch drained via dependent Roux-en-Y gastroenterostomy. Failed gastric bypasses are probably best corrected by dividing along the old staple line, dividing the stomach and creating a partitioned pouch to which a new limb of jejunum may be anastomosed (Figure 9). Failed jejunoileal bypasses or those associated with nutritional deficiencies are best converted to gastric bypass as well. In complex cases, BPD may be a good option to rescue patients who are continuing to fail other procedures. CONCLUSION Obesity is an increasing health problem in the USA. The subgroup of severely obese patients are particularly at risk, with limited personal lives, serious associated illnesses and a markedly increased mortality. Medical therapy, including diets and behavioural modification, is ineffective in these patients and may, in fact, delay necessary therapy. Bariatric surgery remains the only safe and effective means of treating not only the obesity, but also the life-threatening and psychosocial complications that define severe obesity.

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Figure 9. Divided gastric bypass. This procedure is used as a primary operation by some surgeons and for the revision of failed bariatric operations by most. In this model, the gastric pouch has been separated from the stomach vertically and anastomosed, end to end, to the Roux-en-Y loop. Some surgeons fix the jejunum to the gastric staple line to prevent a gastro-gastric fistula.

Three operations, gastric bypass, VBG and gastric banding have produced the best results to date. The pronounced weight loss that can be induced with these operations can relieve and bring co-morbid diseases, such as diabetes and hypertension, once thought to be only barely controllable, into full long-term remission. REFERENCES * 1. Kuczmarski RJ (1992) Prevalence of overweight and weight gain in the United States. American Journal of Clinical Nutrition 55 (supplement): 495S–502S. * 2. Sjöström L (1992) Morbidity of severely obese subjects. 1992; American Journal of Clinical Nutrition 55 (supplement): 508S–515S. 3. Lew EA & Garfinkel L (1979) Variations in mortality by weight among 750,000 men and women. Journal of Chronic Diseases 32: 563–576. 4. Wolf AM & Colditz GA (1996) American Journal of Clinical Nutrition 63 (supplement 3): 466S–469S. 5. Martin LF, Hunter SM, Lauve RM & O’Leary JP (1995) Severe obesity: expensive to society, frustrating to treat, but important to confront. Southern Medical Journal 88: 895–902. 6. Bjorvell H & Rossner SA (1990) A ten-year follow up of weight change in severely obese subjects treated in a behavioral modification-like program. International Journal of Obesity 14: 88. * 7. Kellum JM, DeMaria EJ & Sugerman HJ (1988) The surgical treatment of morbid obesity. Current Problems in Surgery 35: 791–858. 8. Anonymous (1992) Gastrointestinal surgery for severe obesity. National Institutes of Health Consensus Development Conference Statement. American Journal of Clinical Nutrition 55 (supplement 2): 615S–619S. * 9. Bray CA (1989) Classification and evaluation of obesities. Medical Clinics of North America 73: 161–184. 10. Kremen AJ, Linner JH & Nelson CH (1954) An experimental evaluation of the nutritional importance of the proximal and distal small intestine. Annals of Surgery 140: 439. 11. Payne JH & DeWind LT (1969) Surgical treatment of obesity. American Journal of Surgery 118: 141. 12. Scott HW, Dean RH & Shull HJ et al (1977) Results of jejunoileal bypass in two hundred patients with morbid obesity. Surgery, Gynecology and Obstetrics 145: 661. 13. Buchwald H, Varco RL, Moore RB et al (1975) Intestinal bypass procedures Current Problems in Surgery (April): 1–51 (review).

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14. Luyckx FH, Desaive C, Thiry A et al (1998) Liver abnormalities in severely obese subjects: effect of drastic weight loss after gastroplasty. International Journal of Obesity and Related Metabolic Disorders 22(3): 222–226. 15. O’Leary P (1992) Gastrointestinal malabsorptive procedures. American Journal of Clinical Nutrition 55 (supplement): 567S–570S. 16. Mason EE & Ito C (1969) Gastric bypass. Annals of Surgery 170: 329. 17. Scopinaro N, Gianetta E, Civalleri D et al (1980) Two years of clinical experience with the biliopancreatic bypass for obesity. American Journal of Clinical Nutrition 33: 506–514. 18. Mason EE (1982) Vertical banded gastroplasty for obesity. Archives of Surgery 117: 701–706. 19. Lindroos AK, Lissner L & Sjöström L (1996) Weight change in relation to intake of sugar and sweet foods before and after weight reducing gastric surgery. International Journal of Obesity and Related Metabolic Disorders 20: 624–642. *20. Brolin RL, Robertson LB, Kenler HA & Cody RP (1994) Weight loss and dietary intake after vertical banded gastroplasty and Roux-en-Y gastric bypass. Annals of Surgery 220: 782–790. *21. Sugerman HJ, Starkey JV & Birkenhauer R (1987) A randomized prospective trial of gastric bypass vs. vertical banded gastroplasty for morbid obesity and their effects on sweets vs. non-sweets eaters. Annals of Surgery 205: 613–624. 22. Sugerman HJ, Londrey GL, Kellum JM et al (1989) Weight loss with vertical banded gastroplasty and Roux-Y gastric bypass for morbid obesity with selective versus random assignment. American Journal of Surgery 157: 93–102. 23. Wilkinson LH & Peloso OA (1981) Gastric (reservoir) reduction for morbid obesity. Archives of Surgery 116: 602. 24. Molina M (1984) Gastric Banding, an Experience with more than 500 Cases. Presented at the Symposium on Surgical Treatment of Obesity, Los Angeles CA, USA. *25. Kuzmak L (1989) Gastric banding. In Dietel M (ed.) Surgery for the Morbidly Obese Patients pp 225–259. Philadelphia: Lea & Febiger. 26. Belachew M (1994) Laparoscopic adjustable silicone gastric banding (LASGB) in the treatment of morbid obesity: a preliminary report: a video film. Obesity Surgery 4: 180–181. 27. Belachew M & Monami B (1996) Weight loss comparison between vertical banded gastroplasty (VBG), open adjustable silicone gastric banding (ASGB), and laparoscopic adjustable silicone gastric banding (LASGB). Obesity Surgery 6: 123 (abstract). 28. Kark AF (1980) Jaw Wiring. American Journal of Clinical Nutrition 33: 420. 29. Garren LR & Garren M (1984) The Garren gastric bubble: an endoscopic aid to treatment of morbid obesity. Gastrointestinal Endoscopy 30: 153. 30. Meshkinpour H, Hsu D & Farivar S (1988) Effect of gastric bubble as a weight reduction device: a controlled, crossover study. Gastroenterology 95: 589–592. 31. Kuzmak LI (1991) A review of seven years’ experience with silicone gastric banding. Obesity Surgery 1: 403. 32. Deitel M, Jones BA, Petrov I et al (1986) Vertical banded gastroplasty: results in 233 patients. Canadian Journal of Surgery 29: 322. 33. Ramsey-Stewart G (1995) Vertical banded gastroplasty for morbid obesity: weight loss at short and long-term follow-up. Australian and New Zealand Journal of Surgery 65: 4–7. 34. Kellum JM, Kuemmerle JF, O’Dorisio TM et al (1990) Gastrointestinal hormone responses to meals before and after gastric bypass and vertical banded gastroplasty. Annals of Surgery 211: 63–71. 35. Scopinaro N, Gianetti D, Adami G et al (1996) Biliopancreatic diversion for obesity at eighteen years. Surgery 119: 261–268. 36. Hall JC, Watts JM, O’Brien PE et al (1990) Gastric surgery for morbid obesity. The Adelaide study. Annals of Surgery 211: 419–427. 37. Capella JF & Capella RF (1996) The weight reduction operation of choice: vertical banded gastroplasty or gastric bypass? American Journal of Surgery, 171: 74–79. 38. Benotti P, Bistrian B, Benotti J et al (1992) Heart disease and hypertension in severe obesity: the benefits of weight reduction. American Journal of Clinical Nutrition 55 (supplement): 586S–590S. 39. Eliahou HFE, Liana A, Gaon T et al (1981) Body weight reduction necessary to attain normotension in the overweight hypertensive patient. International Journal of Obesity 5: 157–163. 40. Foley EF, Benotti PN, Borlase BC et al (1992) Impact of gastric bypass surgery on hypertension in morbidly obese patients. American Journal of Surgery, 163: 294–297. 41. Alaud-din A, Meterissan S, Lisbona R et al (1990) Assessment of cardiac function in patients who were morbidly obese. Surgery 108: 809–820. 42. Backman L, Freyschuss U, Hallberg D & Melcher A (1970) Reversibility of cardiovascular changes in extreme obesity. Effects of weight reduction through jejunoileostomy. Acta Medica Scandinavica 205: 367–373.

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