Surgical Management of Severe Obesity in Adolescents

Surgical management of severe obesity in adolescents

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Official reprint from UpToDate® www.uptodate.com ©2012 UpToDate®

Surgical management of severe obesity in adolescents Authors Stavra A Xanthakos, MD, MS Thomas H Inge, MD, PhD

Section Editors William J Klish, MD Daniel Jones, MD

Deputy Editor Alison G Hoppin, Hoppin, MD

Disclosures All topics are updated updated as new new evidence becomes becomes available available and our peer our peer review review process is complete. Literature review current through: Apr 2012. | This topic last updated: ene 16, 2012. INTRODUCTION — During the past few years, severe obesity has gained recognition recognition as a significant health problem facing a large proportion of adults and children in the United States [1,2 1,2]. ]. Due to a lack of nonsurgical options for extremely obese adolescents and a demonstrated safety and efficacy record in adults, there has been increasing interest in surgical procedure procedures s for weight loss ("bariatric surgery") surgery") for selected obese adolescents with severe obesity. The rationale, rational e, outcomes outcomes,, and indications for weight loss surgery in adolescents will be reviewed here. The management and outcomes of weight loss surgery in adults and other aspects of obesity in children and adolescents are discussed separately. (See "Surgical management of severe obesity" and "Medical management of patients after bariatric surgery" and "Clinical evaluation of the obese child and adolescent" and "Comorbidit "Comorbidities ies and complications of obesity in children and adolescents" and "Definition; epidemiology; epidemiology; and etiology of obesity in children and adolescents" and "Manageme "Management nt of childhood obesity in the primary care setting" .) RATIONALE — Children and adolescents with severe obesity are at risk for important comorbidities, including obstructive sleep apnea, diabetes, hypertension, cardiac hypertrophy hypertrophy,, and nonalcoholic steatohepatiti steatohep atitis, s, as well as depression and impaired quality of life [ 3-6 3-6]. ]. Therefore, treatment that is targeted at obesity may treat or prevent these problems and improve longterm health outcomes. (See "Comorbiditie "Comorbidities s and complications of obesity in children an d adolescents" adolescents".) .) History of weight loss surgery — During the past 30 to 40 years, weight loss surgery has clearly been shown to produce significant and sustained reductions in BMI, diabetes, and hypertriglyceridemia hypertriglyceridemia in adults. It also reduces mortality, as highlighted in a 10-year follow-up of patients undergoing gastric bypass, banding, or vertical gastroplasty in the Swedish Obesity Study [7 [7,8 ,8]. ]. (See "Surgical management of severe obesity" .) Weight loss surgery has been performed in small groups of adolesc ents since the late 1970s. An analysis of representative national hospital administrative data from the United States demon demonstrated strated that between 199 1996 6 and 2000, the annual number of surgical weight loss procedures in adolescents remained stable [ 9]. However, between 2000 and 2003, the rate of surgical weight loss procedures in adolescents tripled to an estimated 771 procedures nationwide [ 9]. In a survey of bariatric surgeons in the United States in 2005, 75 percent indicated they were planning to perf orm orm an adolescent procedure in the u pcoming year, and 42 percent were in the process of developing a multi-disciplinary adolescent weight loss surgery program in their community [10 [ 10]. ]. Nonetheless, weight loss surgery for adolescents remains a small percentage of overall annual weight loss surgery procedures in the United States (0.7 percent), with the majority of these cases (90 percent) being gastric bypass [ 9]. Defining severe obesity — When evaluating the risks and benefits of surgery, an important step is to identify the group of patients that are most likely to benefit from the intervention. In adu adults, severe obesity is generally defined as a body mass index (BMI) !40 kg/m2. This is also the BMI threshold for consideration of surgery as proposed by an NIH consensus panel; a threshold of 35 kg/m2 is used for adults with significant current comorbidities comorbidities such as diabetes [ 11 11]. ]. (See "Surgical management of severe obesity" .) In children, a BMI !120 percent of the 95th percentile, or !35 kg/m2 defines a group that is at high risk for medical complications of obesity in the long term [ 12 12]. ]. This threshold corresponds to approx approximately imately the 99th percentile (z-score 2.33), but is preferred because becaus e the CDC growth standards are not sufficiently precise to use percentile curves at the extremes [ 13 13]. ]. In the United States, approximately 4 percent of children 5 to 17 years of age are currently in this range [ 14 14]. ]. These children will almost always remain in the obese range as adults, and 65 percent will have Class III obesity as adults (BMI !40) [14,15 [14,15]. ]. They have a significantly greater prevalence prevalence of cardiovascular risk factors as compared with children with lesser degrees of obesity, and will have more health complications and higher mortali ty as compared compared with those who developed obesity during adulthood [ 16-18 16-18]. ]. For boys, the 99th percentile for BMI is approximately approximately 32 kg/m2 at 13 years of age and rises to 34 at 16 years of age. For girls, the 99th percentile for BMI is approximately 34 at 13 years of age, and rises to 36 kg/m2 at age 15, and 38 by age 16. Therefore, use of an absolute BMI !35 will define a subgroup of patients with a degree of obesity that is even more severe than that defined by the 99th percentile for all adolescent boys, and is particularly conservative conservative for younger adolescents. A few girls over age 14 may have a BMI !35 but not above the 99th percentile for their age. A BMI !40 will define a subgroup of patients with very severe obesity, and is above the 99th percentile for virtually all adolescents. Z-scores provide an alternative method of defining severe obesity in children and adolescents. Z-scores correspond directly to percentiles. As an example, the 95th percentile corresponds corresponds to a z-score of 1.65, the 97th percentile to a z-score of 1.89, and the 99th percentile to a z-score of 2.33. However, z-scores beyond the 97th percentile have been calculated using mathematical mathematical equations derived from population-based data between the 3rd and 97th percentile due to insufficient numbers of subjects with BMI values greater than the 97th percentile in national samples. For this reason, actual BMI values can vary widely at percentiles above the 99th percentile. BMI percentiles and z-scores can be determined using a gender-specific calculator for boys (calculator ( calculator 1) 1) or for girls (calculator ( calculator 2). 2). Further work is needed to correlate these different thresholds for defining severe obesity to current and future risks of clinical comorbidities and, thereby, to the potential benefits and risks of surgery. Alternatives — Because of the potential risks of surgical weight loss, non-invasive approaches approaches should always be the first-line treatment for any child or adolescent with obesity. The best established approaches approaches are multidisciplinary, using family-based behavioral techniques to support changes in diet and physical activity, with goals of reducing caloric intake, improving the quality of the food intake, and increasing energy expenditure [ 12 12]. ]. Recommendations from an expert committee, endorsed by the American Academy of Pediatrics and other professional organizations, advocate a staged approach to weight management based on the child's degree of obesity and response to previous interventions [ 12,19 12,19]. ]. Unfortunately, Unfortunately, the limited data available suggest that dietary and behavioral interventions interventions alone rarely achieve long-term success for individuals with severe obesity. In one study of 24 preadolescent preadolescent children with severe obesity (mean BMI 34 kg/m2, ages 8 to 12) weight loss during a 12-week behavioral program was modest; children lost an average of 2.5 kg (3.2 percent) of their initial weight [[20 20]. ]. At follow-up seven months later, all lost weight had been regained. In another study of 12 adolescents with BMI values !40 kg/m2 (mean BMI 47 kg/m2) participating in a pediatric behavioral weight loss treatment program, program, the subjects had only a 3 percent reduction of BMI (mean 46 kg/m2) after one year [ 21 21]. ]. Finally, obese adolescents randomized to placebo and behavioral therapy (eg, controls in pharmaceutical pharmaceutical studies for weight loss) have typically demonstrated <3 percent weight loss [ 22,23 22,23]. ]. These studies suggest that dietary and behavioral interventions generally have poor success rates for adolescents with severe obesity. TYPES OF SURGERY — Currently, the most widely performed procedures procedures in adolescents and adults are the roux-en-Y gastric bypass ( figure 1) 1) and the adjustable gastric band (AGB) (figure 2). 2). (See "Surgical management of severe obesity", section on 'Bariatric surgical procedures' .) The Food and Drug Association (FDA) has approved two adjustable gastric band devices for use in adults in the United States, but these devices are not yet FDA-approved for adolescents younger than age 18. An industry-sponsored industry-sponsored prospective study is in progress, and numerous retrospective studies of adolescents have been published with favorable results (see 'Outcomes' below). The vertical sleeve gastrectomy has gained increased interest interest as a type of weight loss surgery in adults and adolescents ( figure 3). 3). The sleeve gastrectomy gastrectomy was originally performed as the first part of a two-stage weight loss procedure for high risk extremely obese patients. The sleeve gastrectomy gastrectomy was performed first to promote initial weight loss, and was followed at a later stage by the bilio-pancreatic bilio-pancreatic diversion with duodenal switch (BPD/DS) or roux-en-Y gastric bypass (RYGB) as the final weight loss procedure. However, accumulating short term data in adults suggest that similar degrees of weight loss and comorbidity resolution occur within one to three years after small-caliber sleeve gastrectomy alone, prompting increasing use of this procedure as a stand-alone weight loss surgery [ 24 24]. ]. Data on long-term outcomes is pending. (See "Surgical management of severe obesity", section on 'Sleeve gastrectom gastrectomy' y' .) Because the sleeve gastrectomy is less complex and has a lower risk of micronutrient deficiencies deficiencies as compared to malabsorptive procedures, procedures, it is an attractive option. Additionally, if long-

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term weight regain occurs, the option of converting to a RYGB or BPD/DS remains. A small case series of four adolescents undergoing sleeve gastrectomy has also been reported with good safety and efficacy outcomes at one year [ 25]. In the past, the range of surgical weight loss procedures performed on adults and a few adolescents included jejunoileal bypass (a procedure associated with a high rate of malabsorptive complications), vertical banded gastroplasty, and banded gastric bypass. Due to unsatisfactory safety profiles and/or efficacy, these procedures are no longer recommended. Other procedures that cause malabsorption, such as biliopancreatic diversion, are occasionally performed on adults but are generally not recommended for adolescents due to lack of safety data in this age group and concerns about long-term nutritional complications. MECHANISMS OF WEIGHT LOSS — Reduction of caloric intake plays an important role in the dramatic weight loss produced by bariatric surgery. However, this may not be purely due to reduced capacity of the stomach or pouch. Many patients report a subjective decrease in appetite and increase in postprandial satiety after surgery, which helps them maintain lower intake of food. This experience suggests that the effects of bariatric surgery on weight loss and comorbidities may have neuroendocrine mechanisms, and are not due to mechanical restriction of food intake or of malabsorption. Emerging data suggest that alterations in neuro-enteric hormones that regulate appetite and energy expenditure could contribute to changes in satiety after surgery. Several studies have demonstrated an increase in postprandial total peptide YY (both PYY and PYY3-36) after roux-en-Y gastric bypass compared with lean or obese nonoperative controls [ 26,27]. This postprandial increase in PYY is not reported after an adjustable gastric band [ 28,29]. However, a single series of 12 patients undergoing the vertical banded gastroplasty (also purely restrictive) reported an increase in fasting and postprandial PYY after surgery to levels comparable to those measured in lean controls [ 30]. Dramatic improvements in insulin resistance and diabetes occur after gastric bypass, even prior to any significant weight loss. These changes may in part be due to increased secretion of incretins, such as glucagon-like-peptide-1 (GLP-1) by intestinal endocrine cells after surgery. After gastric bypass, postprandial GLP-1 plasma levels rise dramatically as compared to levels in lean and obese controls, and as compared to patients undergoing adjustable gastric banding [ 29]. Further research is needed to elucidate the mechanisms through which bariatric surgery causes this abrupt enhancement of insulin sensitivity. OUTCOMES Weight loss — Virtually all studies reporting outcomes of weight loss surgery in adolescents have utilized a retrospective design and report short- to intermediate-term outcomes (outcomes measured from 1 to 6.3 years after surgery). A few studies have reported small numbers of patients 10 or more years after their procedure. In most of these long-term studies, a substantial number of subjects were lost to follow-up, which could bias findings. Despite these limitations, the existing retrospective data clearly demonstrate that both gastric bypass and banding in adolescents lead to clinically important and durable decreases in weight and BMI in the majority of patients. The largest retrospective series of adolescents after gastric bypass reported a 37 percent overall reduction in BMI at one year postoperatively [ 21]. The nadir postoperative BMI tends to be lower in patients with less severe obesity preoperatively as compared to those with more severe obesity, although the percent BMI change is similar. In a large series of patients from a single center, the mean nadir postoperative BMI was 31, 38, and 47 kg/m2 for patients with starting BMIs between 40 to 54, 55 to 65, and >65 kg/m2, respectively [31]. Weight loss outcomes are often reported as percentage of excess weight loss (EWL). Several series have reported 56 to 62 percent EWL after roux-en-Y gastric bypass [32,33]. Comparable results have been reported after adjustable gastric banding (AGB) in adolescents. In two studies of adolescents undergoing AGB, mean weight loss after ranged from 52 to 60 percent EWL at one- and two-years follow-up [ 34-36]. The rate of weight loss appears to be more gradual after AGB as compared with gastric bypass, with maximal weight loss in AGB achieved at 12 or more months after surgery [ 34,35]. One study reported 70 percent EWL (range 37 to 101 percent) in 18 patients followed for three years after AGB [ 37]. The relatively high EWL in this group might be explained by the fact that participants had relatively mild obesity prior to surgery (mean BMI 42) as compared to other series. A prospective series reported somewhat less weight loss (34 percent EWL at 12 months and 41 percent EWL at 18 months) [ 38]. This study was limited by a 20 percent dropout rate (5 of 25 patients were unavailable for data collection). A randomized trial of 50 adolescents compared AGB to a supervised lifestyle intervention, with two-year follow-up [ 39]. The patients in the AGB group lost an average of 34.6 kg or 79 percent EWL, as compared with 3.0 kg or 13 percent EWL in the lifestyle group. The study was limited by a 28 percent dropout rate in the lifestyle group (18 of 25 patients completed the study). Of note, almost 30 percent of the patients undergoing AGB required revisional procedures. (See 'Long-term complications' below.) Weight loss after surgery is accompanied by a significant reduction in body fat (from 51 percent to 37 percent in one series) with a relative preservation of lean body mass [ 40]. Not surprisingly, given the improvement in adiposity, obesity-related diseases usually improve or resolve after surgically induced weight loss in adolescents. The most dramatic improvements have been seen in insulin resistance, triglyceride levels, diabetes, obstructive sleep apnea, as well as depression and quality of life [ 4,21,37,41,42]. One study also showed improvements in obesity-associated cardiac abnormalities, including concentric left ventricular hypertrophy and diastolic function, as measured by echocardiogram performed before and 10 ± 3 months after gastric bypass surgery [ 43]. It is not clear to what degree weight loss will be sustained in adolescents and whether comorbid conditions will recur if significant weight is regained in long-term follow-up. Two studies with 4 to 10 years of follow-up suggest that 10 to 15 percent of patients regain significant weight after gastric bypass procedures [ 32,44]. A substantial number of patients also regain some or all of their lost weight after adjustable gastric banding. In one retrospective series of 24 adolescents, maximal EWL (52 percent) occurred at one year after adjustable gastric banding with a regression to 42 percent EWL at two and three years [ 35]. Specific predictors of weight regain after surgical weight loss procedures are unknown for adults and adolescents. There is still insufficient information to directly compare the long-term weight loss outcomes of roux-en-Y gastric bypass to those for adjustable gastric banding or sleeve gastrectomy in adolescents. Short-term complications — Perioperative complications (<30 days) are generally similar to those in adults. Complications after gastric bypass include intestinal leakage at anastomotic sites, wound infections, pulmonary embolus, gastrojejunal strictures requiring endoscopic dilatation, small bowel obstruction, gastrogastric fistula formation, and symptomatic cholelithiasis [33]. Complications of AGB procedures in adolescents and adults include band slippage requiring repositioning, gastric obstruction, and esophageal or gastric pouch dilatation [ 35]. (See "Complications of bariatric surgery".) Several studies performed in the United States suggest weight loss surgery may be somewhat safer in adolescents as compared with adults. The reason for this is unknown, but the observation may reflect a better state of health among individuals undergoing surgery at a young age. A national analysis of weight loss surgery using utilization codes revealed no perioperative mortality and a significantly shorter length of stay in adolescents as compared with adults [9]. Five percent of adolescent patients had major complications, but the majority (78.3 percent) was respiratory in nature. A large study comparing the perioperative outcomes of weight loss surgery between 309 adolescents and 55,192 adults (>18 years) found that the overall 30-day complication rate was significantly lower in adolescents (5.5 percent) as compared to adults (9.8 percent). There was no difference in observed/expected mortality ratios. The 30-day morbidity and mortality rates for adolescents following restrictive procedures (adjustable gastric banding and gastroplasty) were nil, in comparison with the morbidity rate of 4.3 percent for laparoscopic gastric bypass, and 7.6 percent for open gastric bypass [ 45]. Long-term complications — Long-term complications of weight loss surgery in adolescents are primarily nutritional. In particular, patients are at risk for deficiency of iron, vitamin B12, vitamin D, and thiamine. For this reason, life-long vitamin and mineral supplementation is imperative. However, adherence to supplementation regimens among adolescents may be poor; one study reported that only 13 percent of adolescents were adherent to all prescribed nutritional supplementation [ 32,44]. The specific recommendations are outlined below. (See 'Nutritional supplements' below.) Gastric bypass is associated with reduced bone mass in adults and is probably caused by a combination of reduced mechanical load, changes in adipogenic hormones, and nutritional deficiencies. In adolescents, reduced bone mass has been noted two years after weight loss surgery, but remains appropriate for age [ 46]. As in adults, long-term studies are lacking, and the clinical implications of these changes are unclear. However, these findings underscore the importance of supplementing and monitoring vitamin D and calcium after weight loss surgery. (See 'Nutritional supplements' below and 'Nutritional monitoring' below.) Some adult patients have developed severe postprandial hypoglycemia after gastric bypass [ 47,48]. The exact cause of these hypoglycemic episodes is not known but may result in part from increased incretin secretion after surgery, pancreatic islet cell hyperplasia, and inappropriate postprandial hyperinsulinemia [ 49]. Although a similar syndrome in adolescents after gastric bypass has not yet been reported in the literature, at least one adolescent patient in the authors' weight loss surgery program developed severe postprandial hyperinsulinemia after gastric bypass. Dietary management by providing small meals with relatively low content of carbohydrates was successful in controlling symptoms. Therefore, it is important to query adolescents

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seen in follow-up about symptoms that may suggest postprandial hypoglycemia. Long-term follow-up of adjustable gastric banding (AGB) in adult patients indicates that reoperations due to complications, including slippage, erosion, or device failure, occurs in 10 to 32 percent of adults [50,51]. One prospective evaluation of adults undergoing AGB in Sweden indicated that one-third of the 196 patients experienced a major reoperation: 18 percent had a band replacement and 14 percent had removal [ 51]. Late complications included band migration, leakage, slippage, and pouch dilatation, as well as device-related problems, such as tube replacement and port-related complications. There is a substantial risk that patients undergoing AGB will require reoperation during the first few years after the initial procedure; rates of adverse events over longer follow up periods are not yet available. During the randomized trial of AGB in 25 adolescent patients cited above, eight reoperations (33 percent) were required in a total of seven patients during the two year follow-up period [39]. Six of the procedures were for pouch dilation, and two were for tubing injuries. Other adverse events reported among the 25 patients with AGB in this trial were cholelithiasis requiring cholecystectomy (one patient), unplanned pregnancy (two patients), and depression requiring hospital admission (one patient). These rates were similar to those in the lifestyle group. PREOPERATIVE EVALUATION AND SCREENING Screening — Recommended screening prior to surgical weight loss procedures includes evaluation for the presence and severity of coexisting diseases, as well as assessment of the patient's and family's understanding and readiness for a life-changing and often permanent procedure. The table highlights the recommended screening tests and evaluations that should be completed during the evaluation ( table 1). The final decision on whether to proceed with surgery must be made by the multidisciplinary team, taking into consideration both objective and subjective assessments of the patient's severity of obesity and related diseases, risk of future health problems, failure to lose weight through more conventional means, psychosocial status and support, and patient and family readiness for surgery. A multidisciplinary approach is recommended when offering weight loss surgery to extremely obese adolescents [ 52-54]. At a minimum, the team evaluating and caring for the candidate should include an experienced bariatric surgeon, pediatric obesity specialist, nurse, dietician, and pediatric psychologist or psychiatrist. One of these providers or an additional team member should have responsibility for coordinating each patient's care and ensuring follow-up and adherence to the prescribed medical regimen. The program also must have ready access to relevant pediatric subspecialties, including endocrinology, cardiology, gastroenterology, pulmonology, gynecology, and orthopedics for further evaluation and/or management of specific comorbidities as needed. Patient selection — In adults, the threshold for consideration of weight loss surgery is a BMI !40 kg/m2; a threshold of 35 kg/m2 is used for individuals with significant current comorbidities, such as diabetes. For adjustable banding, the threshold for adults with significant comorbidities is a BMI>30 kg/m2. (See "Surgical management of severe obesity" .) In adolescents, BMI percentile curves increase with age and vary by gender. This creates some difficulty using a flat threshold for BMI during a period of continued linear growth and applied to both genders. The use of a flat BMI cutpoint as a minimum threshold for consideration of weight loss surgery has the advantage of being more conservative at younger ages (ie, corresponding to a higher BMI percentile or z-score). However, it also underestimates the severity of obesity in younger male adolescents (ages 13 to 17) in which a BMI of 40 corresponds to a BMI percentile significantly greatly than the 99th percentile. Therefore, as more information becomes available about the outcomes of weight loss surgery in adolescents, as well as the natural history and distribution of severe obesity in adolescents, it is possible that an age-specific threshold (percentile or z-score) will become more appropriate than a flat BMI threshold. Current z-scores corresponding to BMI values above the 97th percentile have been calculated using mathematical equations derived from the population data used to generate the 3rd to 97th percentiles. Therefore, extrapolation of percentiles and z-scores beyond the 97th percentile must be done cautiously due to the potential wide variability around the percentile lines. (See 'Defining severe obesity' above.) The most widely accepted BMI criteria for weight loss surgery in adolescents include a BMI !40 kg/m2 with one or more significant obesity-related disorders (eg, type 2 diabetes mellitus, obstructive sleep apnea, pseudotumor cerebri, or severe steatohepatitis), or a BMI of !50 with more minor comorbidities (hypertension, dyslipidemia, mild steatohepatitis, significant impairment in quality of life, or arthropathy) [ 52,54,55]. However, because of mounting evidence of the adverse long-term consequences of severe adolescent obesity, and favorable safety outcomes of surgery in adolescents, a panel of pediatric obesity and bariatric surgery experts has recommended modifying these criteria. The proposed new criteria include the following [ 56]: BMI !35 kg/m2 and a severe comorbidity that has significant short-term effects on health, such as severe obstructive sleep apnea, diabetes mellitus type 2, pseudotumor cerebri or severe and progressive steatohepatitis, OR BMI !40 with more minor comorbidities. Physical maturity, defined as completing 95 percent of predicted adult stature based on bone age or reaching Tanner stage IV. This criterion is based on theoretical concerns that rapid weight loss after gastric bypass might inhibit statural growth if an adolescent has not reached near adult height. It may not be necessary for adjustable gastric banding procedures because weight loss is usually more gradual. (See "Normal puberty", section on 'Tanner stages' and "The child with tall stature or abnormally rapid growth", section on 'Bone age and prediction of height potential' .) History of sustained efforts to lose weight through changes in diet and physical activity. There is no evidence that prolonged preoperative weight management programs enhance selection of patients for weight loss surgery. However, consistent attendance in such a treatment program may be a valuable indicator of the patient's ability to understand and adhere to medical and nutritional recommendations postoperatively. It should be recognized that the above criteria alone are not sufficient to select the patients who are most likely to benefit from weight loss surgery during adolescence. We recommend that the multidisciplinary team consider carefully whether the patient and family have the ability and motivation to adhere to recommended treatments pre- and post-operatively, including consistent use of micronutrient supplements. Evidence may include a history of reliable attendance at office visits for weight management and compliance with other medical needs. In addition, the team should consider whether the adolescent shows evidence of mature decision-making, with appropriate understanding of the risks and benefits of surgery, and has support but not coercion from family members. Contraindications for surgical weight loss procedures in adolescents include: Medically correctable cause of obesity An ongoing substance abuse problem (within the preceding year) A medical, psychiatric, psychosocial, or cognitive condition that prevents adherence to post-operative dietary and medication regimens or impairs decisional capacity Current or planned pregnancy within 12 to 18 months of the procedure Inability on the part of the patient or parent to comprehend the risks and benefits of the surgical procedure The risks and benefits of weight loss surgery for individuals with syndromic obesity (eg, Prader-Willi syndrome) have not been adequately explored, and more investigation is required before use of surgery can be widely recommended [ 57]. It is unclear whether weight loss surgery is effective for these individuals, and they may have increased risks for complications, such as gastric rupture. (See "Clinical features, diagnosis, and treatment of Prader-Willi syndrome" .) PERIOPERATIVE SAFETY — To provide for optimum safety of the patient while hospitalized, it is important to ensure that the program also has access to pediatric anesthesiology and radiology consultants who have experience caring for individuals with severe obesity. Specialized equipment, such as CT, MRI, and DEXA scanners, often have weight limitations, which may preclude their use for these patients [ 58]. Further, basic equipment such as operating tables, stretchers, scales, beds, and toilets that can support extreme weight ranges must be available to ensure safety of the patient and caretakers. To prevent the development of venous thromboembolism, we recommend the use of compression boots until the patient is ambulatory. Patients at increased risk for deep vein thrombosis and thromboembolism (eg, those with severely impaired mobility or a hypercoagulable state) are often treated with low-molecular weight heparin in the perioperative period. (See "Complications of bariatric surgery", section on 'Pulmonary embolism and deep venous thrombosis' and "Management of the critically ill obese patient", section on 'Venous thromboembolism' .) Weight loss surgery frequently leads to an abrupt resolution of hypertension and hyperglycemia. Antihypertensive or hypoglycemic medications that were given preoperatively usually can be discontinued after surgery, and the patient should be monitored for his or her response. (See "Medical management of patients after bariatric surgery", section on 'Medication management' .)


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POSTOPERATIVE MANAGEMENT — Average inpatient stays range from three to four days for laparoscopic roux-en-y gastric bypass and from one to two days for laparoscopic adjustable gastric banding. Postoperative management for patients includes strict measurement of intake and output, monitoring of drain output (after roux-en-y gastric bypass) to evaluate for potential leak, and gradual advancement of diet from NPO to clear liquids to a high-protein liquid diet. (See "Medical management of patients after bariatric surgery", section on 'Nutritional management' .) Diet — Dietary management after discharge varies with the type of surgery. After roux-en-y gastric bypass, the patient advances through several stages, from high-protein shakes to gradual introduction of greater volumes and more textured and solid foods [ 59]. The advancement to regular foods is slow, occurring over the first six months after surgery. For best results, the patient is encouraged to eat three to four small, high-protein meals per day and to avoid high-fat and carbohydrate foods, as these may provoke malabsorptive or dumping side effects. Supplemental fluids are encouraged to avoid dehydration (64 to 92 ounces per day of sugar-free, noncarbonated beverages). Drinks should be sugar-free to avoid dumping syndrome and weight regain through over-consumption of liquid calories. Patients also are advised to avoid drinking during meals to avoid nausea and vomiting. After adjustable gastric banding, patients are able to return to a regular diet more quickly [ 59]. The tightness of the band is sequentially adjusted (every four to six weeks during the first one to two years) to maintain satiety and restrict food intake. If large volumes of food are eaten quickly, vomiting may result, which may provide an additional incentive to limit intake. Three to four small meals are recommended, again with high-protein content, to maintain lean body mass during the weight loss. The patient gradually learns to feel sated with smaller volumes of meals and to chew more slowly. Excessive tightening of the band may result in recurrent vomiting, which in turn can lead to nutritional deficiencies, such as beriberi or long-term maladaptive eating behaviors. Follow-up visits for gastric bypass patients are typically performed at two weeks postoperatively, then 1, 3, 6, 9, and 12 months after surgery. After that, annual follow-up is recommended for monitoring of anthropometric measurements, nutritional status, residual comorbidities, and general health. Follow-up for banding patients typically is more frequent due to the need for band adjustments. Some patients require visits every four to six weeks during the first one to two years. General recommendations for long-term weight maintenance include: Drinking 8 to 12 eight-ounce servings of sugar-free liquids per day Exercising 30 to 60 minutes daily Eating protein first at each meal (1 gm/kg of ideal body weight) Three to four portion-controlled meals per day, with minimal snacking between meals Taking daily vitamin and mineral supplementation These guidelines may need to be tailored to meet an individual patient's needs if significant weight regain or too much weight loss has occurred. Nutritional supplements — After gastric bypass or banding procedures, life-long supplementation with vitamins and minerals is recommended to avoid development of nutritional complications secondary to reduced intake and/or mild malabsorption. After roux-en-y gastric bypass, patients should conscientiously adhere to a supplementation regimen because of risks for malabsorption of micronutrients; the recommended doses and preparations vary somewhat among practices and may be adjusted based on laboratory measures. We prescribe the following supplements for all patients ( table 2): Standard multivitamin with folate and iron, or prenatal vitamin if female Vitamin B12, 500 micrograms orally daily Calcium, 1200 to 1500 mg daily (measured as elemental calcium), with 800 mg vitamin D Additional supplementation may be necessary during pregnancy or as indicated by laboratory testing. If postoperative vomiting is severe, vitamin B1 deficiency also can rapidly develop. Vitamin B1 is particularly important to recognize early, as lasting neurologic sequelae can result if rapid replenishment of vitamin B1 is not initiated [ 60]. In the author's program, vitamin B1 supplementation is provided during the first six months after surgery as a prophylactic measure. After adjustable gastric banding, a routine multivitamin may suffice if a well-balanced, healthy diet is consumed. However, menstruating females may require additional iron supplementation, and all patients should have routine monitoring for deficiencies as described below. Nutritional monitoring — After bariatric surgery, life-long monitoring of nutritional status is recommended. In our practice, we measure the following parameters annually: Complete blood cell count with differential Serum iron and ferritin Red blood cell folate, serum vitamin B12, and serum homocysteine Serum thiamine (vitamin B1) Albumin and total protein Alkaline phosphatase, calcium, 25-hydroxy vitamin D, and parathyroid hormone DEXA to monitor lean and fat-free mass, and bone density (this test is optional and may not be needed annually or for patients with good nutritional status) Adjustments in nutritional supplements may need to be made if specific deficiencies emerge over time, particularly because many adolescents may be nonadherent or only partially adherent to recommended supplementation. (See "Medical management of patients after bariatric surgery", section on 'Micronutrient deficiency' .) Pregnancy prevention — Severe obesity can lead to irregular menstruation, anovulation, and infertility. Conversely, surgically induced weight loss leads to resumption of ovulation and renewed fertility for some women [61]. The effects of bariatric surgery on menstrual irregularities and anovulation in adolescents has not been established. However, in a series of 47 adolescent females who had undergone bariatric surgery during adolescence, a higher-than-expected rate of pregnancy was observed (seven pregnancies, six of which occurred between 10 and 22 months postoperatively) [ 62]. Although the medical and psychosocial factors contributing to this high rate could not be addressed in this retrospective report, the high rate of pregnancy highlights the importance of addressing contraception and pregnancy prevention in all female adolescents undergoing bariatric surgery. Pregnancy should absolutely be avoided for at least 12 to 18 months after surgery due to the rapid weight loss and potential micronutrient deficiencies, which may have adverse effects on the mother and fetus. However, long-term effects of bariatric surgery on fertility and pregnancy outcomes are generally good. (See "Medical management of patients after bariatric surgery", section on 'Pregnancy' and "Counseling women about fertility and pregnancy after bariatric surgery" .) The efficacy of oral contraceptives or transdermal contraceptive patches may be compromised in patients with obesity [ 63-65]. This is a significant concern both pre- and postoperatively, as many adolescent patients may still have a postoperative BMI >30kg/m2 despite significant weight loss after surgery. The American College of Obstetricians and Gynecologists (ACOG) recommends using non-oral forms of hormonal contraception in women who have undergone malabsorptive bariatric surgery and desire hormonal contraception. Further, use of oral contraception is associated with an increased risk of thromboembolism, which may compound the higher risk associated with obesity. Depot medroxyprogesterone acetate is effective in overweight or obese women but has been reported to cause significant weight gain (mean of 4 to 9 kg) in overweight or obese adolescents [66,67]. In contrast, the levonorgestrel intrauterine system (Mirena, Bayer Schering Pharma, Berlin, Germany) does not cause weight gain and remains effective in overweight/obese women [68]. It has several notable advantages that make it an optimal choice for adolescent females after bariatric surgery, including five-year efficacy, promotion of amenorrhea (which could help reduce risk of iron deficiency anemia after surgery), and option for placement at time of bariatric surgery [ 69]. Therefore, we consider it a particularly valuable choice for adolescents who have undergone gastric bypass. However, as with all forms of hormonal contraception, adolescents should be counseled to use additional barrier protection against sexually transmitted diseases. These and other considerations about contraceptive choice are discussed separately ( table 3). (See "Counseling women about fertility and pregnancy after bariatric surgery" .) Adolescent females who become pregnant after weight loss surgery should be counseled about adequate macro- and micronutrient intake. At a minimum, a prenatal vitamin with folic acid and iron, 1200 to 1500 mg of calcium citrate with 800 IU vitamin D, and 500 mcg of oral vitamin B12 daily should be prescribed [ 70]. Additional iron supplementation may be necessary in pregnant women after gastric bypass. Iron, folate, and vitamin B12 levels should be monitored during pregnancy and additional supplementation prescribed as indicated by results. Protein


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intake of at least 1 gm/kg of ideal body weight (typically 60 to 80 grams) per day is recommended. SUMMARY AND RECOMMENDATIONS — Surgical weight loss is an appropriate consideration for adolescents with severe obesity and with medical comorbidities who have failed to lose weight through conventional dietary interventions and behavioral modification. The most widely performed procedures in adolescents and adults are the roux-en-Y gastric bypass (RYGB) and adjustable gastric banding (AGB). Other procedures that cause significant malabsorption are generally not recommended for adolescents due to lack of safety data in this age group and concerns about long-term nutritional complications. (See 'Types of surgery' above.) Efficacy and complications There appear to be substantial clinical benefits of weight loss surgery for selected adolescents with severe obesity and medical comorbidities. This statement is based on retrospective studies with outcomes measured less than 10 years postoperatively, and the characteristics of patients included in these studies vary widely. (See 'Outcomes' above.) Reported weight loss for adolescents undergoing weight loss surgery ranges from 52 to 70 percent of excess body weight. In most cases, there are associated improvements in adiposity, insulin resistance, triglyceride levels, diabetes, obstructive sleep apnea, depression, and impaired quality of life. These outcomes are comparable to those reported for adults undergoing weight loss surgery. The rate of weight loss appears to be more gradual after adjustable gastric banding as compared to gastric bypass. (See 'Weight loss' above.) Perioperative complications in adolescents undergoing weight loss surgery are generally similar to those in adults but occur somewhat less frequently. Long-term complications are primarily nutritional and include deficiencies of iron, vitamin B12, vitamin D, and thiamine. Life-long vitamin and mineral supplementation is imperative. However, adherence to supplementation regimens among adolescents may be poor. (See 'Outcomes' above.) Patient selection Weight loss surgery for adolescents should be performed in the context of a multidisciplinary program with specific expertise in adolescent medicine and extensive expertise in bariatric surgery. (See 'Screening' above.) We suggest using a BMI of !35 kg/m2 as a minimum threshold for consideration of weight loss surgery in an adolescent with significant medical comorbidities ( Grade 2C). This is a lower BMI threshold than that proposed in earlier guidelines because emerging data show potential advantages of earlier surgery and good safety outcomes as compared to adults. (See 'Patient selection' above.) Other important criteria for patient selection include physical maturity, lack of medically correctable causes of obesity, and adequate emotional maturity and stability to ensure competent decision-making and good adherence to medical follow-up ( table 1). In addition, most authorities agree that the patient should have failed organized and sustained attempts to lose weight through lifestyle intervention. (See 'Patient selection' above.) Management Perioperative and postoperative management is similar to that for adults undergoing weight loss surgery. Diet recommendations vary depending on the type of procedure and vary slightly among centers. (See 'Perioperative safety' above and 'Diet' above.) For all patients who have undergone roux-en-Y gastric bypass, we suggest treatment with a daily multivitamin, with additional supplements of calcium, vitamin B12, and vitamin D (table 2) (Grade 2B). We perform laboratory monitoring for micronutrient deficiencies at least once annually thereafter. (See 'Nutritional supplements' above and 'Nutritional monitoring' above.) We recommend avoidance of pregnancy for 12 to 18 months after surgical weight loss procedures ( Grade 2B). Because adolescent girls appear to be at high risk for pregnancy after gastric bypass surgery as compared to others in their age group, all girls should have counseling about pregnancy avoidance and assurance of adequate contraception as part of the preparation and follow up after weight loss surgery. (See 'Pregnancy prevention' above.)

Use of UpToDate is subject to the Subscription and License Agreement. REFERENCES 1. Flegal KM, Carroll MD, Ogden CL, Johnson CL. Prevalence and trends in obesity among US adults, 1999-2000. JAMA 2002; 288:1723. 2. Sturm R. Increases in clinically severe obesity in the United States, 1986-2000. Arch Intern Med 2003; 163:2146. 3. Weiss R, Dziura J, Burgert TS, et al. Obesity and the metabolic syndrome in children and adolescents. N Engl J Med 2004; 350:2362. 4. Kalra M, Inge T, Garcia V, et al. Obstructive sleep apnea in extremely overweight adolescents undergoing bariatric surgery. Obes Res 2005; 13:1175. 5. Xanthakos S, Miles L, Bucuvalas J, et al. Histologic spectrum of nonalcoholic fatty liver disease in morbidly obese adolescents. Clin Gastroenterol Hepatol 2006; 4:226. 6. Zeller MH, Roehrig HR, Modi AC, et al. Health-related quality of life and depressive symptoms in adolescents with extreme obesity presenting for bariatric surgery. Pediatrics 2006; 117:1155. 7. Sjöström L, Lindroos AK, Peltonen M, et al. Lifestyle, diabetes, and cardiovascular risk factors 10 years after bariatric surgery. N Engl J Med 2004; 351:2683. 8. Sjöström L, Narbro K, Sjöström CD, et al. Effects of bariatric surgery on mortality in Swedish obese subjects. N Engl J Med 2007; 357:741. 9. Tsai WS, Inge TH, Burd RS. Bariatric surgery in adolescents: recent national trends in use and in-hospital outcome. Arch Pediatr Adolesc Med 2007; 161:217. 10. Allen SR, Lawson L, Garcia V, Inge TH. Attitudes of bariatric surgeons concerning adolescent bariatric surgery (ABS). Obes Surg 2005; 15:1192. 11. NIH conference. Gastrointestinal surgery for severe obesity. Consensus Development Conference Panel. Ann Intern Med 1991; 115:956. 12. Barlow SE, Expert Committee. Expert committee recommendations regarding the prevention, assessment, and treatment of child and adolescent overweight and obesity: summary report. Pediatrics 2007; 120 Suppl 4:S164. 13. Flegal KM, Wei R, Ogden CL, et al. Characterizing extreme values of body mass index-for-age by using the 2000 Centers for Disease Control and Prevention growth charts. Am J Clin Nutr 2009; 90:1314. 14. Freedman DS, Mei Z, Srinivasan SR, et al. Cardiovascular risk factors and excess adiposity among overweight children and adolescents: the Bogalusa Heart Study. J Pediatr 2007; 150:12. 15. Skelton JA, Cook SR, Auinger P, et al. Prevalence and trends of severe obesity among US children and adolescents. Acad Pediatr 2009; 9:322. 16. Bibbins-Domingo K, Coxson P, Pletcher MJ, et al. Adolescent overweight and future adult coronary heart disease. N Engl J Med 2007; 357:2371. 17. Must A, Jacques PF, Dallal GE, et al. Long-term morbidity and mortality of overweight adolescents. A follow-up of the Harvard Growth Study of 1922 to 1935. N Engl J Med 1992; 327:1350. 18. Baker JL, Olsen LW, Sørensen TI. Childhood body-mass index and the risk of coronary heart disease in adulthood. N Engl J Med 2007; 357:2329. 19. Spear BA, Barlow SE, Ervin C, et al. Recommendations for treatment of child and adolescent overweight and obesity. Pediatrics 2007; 120 Suppl 4:S254. 20. Levine MD, Ringham RM, Kalarchian MA, et al. Is family-based behavioral weight control appropriate for severe pediatric obesity? Int J Eat Disord 2001; 30:318. 21. Lawson ML, Kirk S, Mitchell T, et al. One-year outcomes of Roux-en-Y gastric bypass for morbidly obese adolescents: a multicenter study from the Pediatric Bariatric Study Group. J Pediatr Surg 2006; 41:137. 22. Berkowitz RI, Fujioka K, Daniels SR, et al. Effects of sibutramine treatment in obese adolescents: a randomized trial. Ann Intern Med 2006; 145:81. 23. Chanoine JP, Hampl S, Jensen C, et al. Effect of orlistat on weight and body composition in obese adolescents: a randomized controlled trial. JAMA 2005; 293:2873.


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24. Clinical Issues Committee of the American Society for Metabolic and Bariatric Surgery. Updated position statement on sleeve gastrectomy as a bariatric procedure. Surg Obes Relat Dis 2010; 6:1. 25. Till H, Blüher S, Hirsch W, Kiess W. Efficacy of laparoscopic sleeve gastrectomy (LSG) as a stand-alone technique for children with morbid obesity. Obes Surg 2008; 18:1047. 26. Chan JL, Mun EC, Stoyneva V, et al. Peptide YY levels are elevated after gastric bypass surgery. Obesity (Silver Spring) 2006; 14:194. 27. Korner J, Bessler M, Cirilo LJ, et al. Effects of Roux-en-Y gastric bypass surgery on fasting and postprandial concentrations of plasma ghrelin, peptide YY, and insulin. J Clin Endocrinol Metab 2005; 90:359. 28. Korner J, Inabnet W, Conwell IM, et al. Differential effects of gastric bypass and banding on circulating gut hormone and leptin levels. Obesity (Silver Spring) 2006; 14:1553. 29. le Roux CW, Aylwin SJ, Batterham RL, et al. Gut hormone profiles following bariatric surgery favor an anorectic state, facilitate weight loss, and improve metabolic parameters. Ann Surg 2006; 243:108. 30. Alvarez Bartolomé M, Borque M, Martinez-Sarmiento J, et al. Peptide YY secretion in morbidly obese patients before and after vertical banded gastroplasty. Obes Surg 2002; 12:324. 31. Inge TH, Jenkins TM, Zeller M, et al. Baseline BMI is a strong predictor of nadir BMI after adolescent gastric bypass. J Pediatr 2010; 156:103. 32. Strauss RS, Bradley LJ, Brolin RE. Gastric bypass surgery in adolescents with morbid obesity. J Pediatr 2001; 138:499. 33. Sugerman HJ, Sugerman EL, DeMaria EJ, et al. Bariatric surgery for severely obese adolescents. J Gastrointest Surg 2003; 7:102. 34. Al-Qahtani AR. Laparoscopic adjustable gastric banding in adolescent: safety and efficacy. J Pediatr Surg 2007; 42:894. 35. Dillard BE 3rd, Gorodner V, Galvani C, et al. Initial experience with the adjustable gastric band in morbidly obese US adolescents and recommendations for further investigation. J Pediatr Gastroenterol Nutr 2007; 45:240. 36. Nadler EP, Youn HA, Ren CJ, Fielding GA. An update on 73 US obese pediatric patients treated with laparoscopic adjustable gastric banding: comorbidity resolution and compliance data. J Pediatr Surg 2008; 43:141. 37. Fielding GA, Duncombe JE. Laparoscopic adjustable gastric banding in severely obese adolescents. Surg Obes Relat Dis 2005; 1:399. 38. Holterman AX, Browne A, Tussing L, et al. A prospective trial for laparoscopic adjustable gastric banding in morbidly obese adolescents: an interim report of weight loss, metabolic and quality of life outcomes. J Pediatr Surg 2010; 45:74. 39. O'Brien PE, Sawyer SM, Laurie C, et al. Laparoscopic adjustable gastric banding in severely obese adolescents: a randomized trial. JAMA 2010; 303:519. 40. Inge T, Wilson KA, Gamm K, et al. Preferential loss of central (trunk) adiposity in adolescents and young adults after laparoscopic gastric bypass. Surg Obes Relat Dis 2007; 3:153. 41. Loux TJ, Haricharan RN, Clements RH, et al. Health-related quality of life before and after bariatric surgery in adolescents. J Pediatr Surg 2008; 43:1275. 42. Inge TH, Miyano G, Bean J, et al. Reversal of type 2 diabetes mellitus and improvements in cardiovascular risk factors after surgical weight loss in adolescents. Pediatrics 2009; 123:214. 43. Ippisch HM, Inge TH, Daniels SR, et al. Reversibility of cardiac abnormalities in morbidly obese adolescents. J Am Coll Cardiol 2008; 51:1342. 44. Rand CS, Macgregor AM. Adolescents having obesity surgery: a 6-year follow-up. South Med J 1994; 87:1208. 45. Varela JE, Hinojosa MW, Nguyen NT. Perioperative outcomes of bariatric surgery in adolescents compared with adults at academic medical centers. Surg Obes Relat Dis 2007; 3:537. 46. Kaulfers AM, Bean JA, Inge TH, et al. Bone loss in adolescents after bariatric surgery. Pediatrics 2011; 127:e956. 47. Patti ME, McMahon G, Mun EC, et al. Severe hypoglycaemia post-gastric bypass requiring partial pancreatectomy: evidence for inappropriate insulin secretion and pancreatic islet hyperplasia. Diabetologia 2005; 48:2236. 48. Service GJ, Thompson GB, Service FJ, et al. Hyperinsulinemic hypoglycemia with nesidioblastosis after gastric-bypass surgery. N Engl J Med 2005; 353:249. 49. Goldfine AB, Mun EC, Devine E, et al. Patients with neuroglycopenia after gastric bypass surgery have exaggerated incretin and insulin secretory responses to a mixed meal. J Clin Endocrinol Metab 2007; 92:4678. 50. Lyass S, Cunneen SA, Hagiike M, et al. Device-related reoperations after laparoscopic adjustable gastric banding. Am Surg 2005; 71:738. 51. Balsiger BM, Ernst D, Giachino D, et al. Prospective evaluation and 7-year follow-up of Swedish adjustable gastric banding in adults with extreme obesity. J Gastrointest Surg 2007; 11:1470. 52. Inge TH, Krebs NF, Garcia VF, et al. Bariatric surgery for severely overweight adolescents: concerns and recommendations. Pediatrics 2004; 114:217. 53. Apovian CM, Baker C, Ludwig DS, et al. Best practice guidelines in pediatric/adolescent weight loss surgery. Obes Res 2005; 13:274. 54. August GP, Caprio S, Fennoy I, et al. Prevention and treatment of pediatric obesity: an endocrine society clinical practice guideline based on expert opinion. J Clin Endocrinol Metab 2008; 93:4576. 55. Roberge JN, Brubaker PL. Secretion of proglucagon-derived peptides in response to intestinal luminal nutrients. Endocrinology 1991; 128:3169. 56. Pratt JS, Lenders CM, Dionne EA, et al. Best practice updates for pediatric/adolescent weight loss surgery. Obesity (Silver Spring) 2009; 17:901. 57. Scheimann AO, Butler MG, Gourash L, et al. Critical analysis of bariatric procedures in Prader-Willi syndrome. J Pediatr Gastroenterol Nutr 2008; 46:80. 58. Inge TH, Donnelly LF, Vierra M, et al. Managing bariatric patients in a children's hospital: radiologic considerations and limitations. J Pediatr Surg 2005; 40:609. 59. Fullmer MA, Abrams SH, Hrovat K, et al. Nutritional strategy for adolescents undergoing bariatric surgery: report of a working group of the Nutrition Committee of NASPGHAN/NACHRI. J Pediatr Gastroenterol Nutr 2012; 54:125. 60. Towbin A, Inge TH, Garcia VF, et al. Beriberi after gastric bypass surgery in adolescence. J Pediatr 2004; 145:263. 61. Teitelman M, Grotegut CA, Williams NN, Lewis JD. The impact of bariatric surgery on menstrual patterns. Obes Surg 2006; 16:1457. 62. Roehrig HR, Xanthakos SA, Sweeney J, et al. Pregnancy after gastric bypass surgery in adolescents. Obes Surg 2007; 17:873. 63. Holt VL, Cushing-Haugen KL, Daling JR. Body weight and risk of oral contraceptive failure. Obstet Gynecol 2002; 99:820. 64. Holt VL, Scholes D, Wicklund KG, et al. Body mass index, weight, and oral contraceptive failure risk. Obstet Gynecol 2005; 105:46. 65. Zieman M, Guillebaud J, Weisberg E, et al. Contraceptive efficacy and cycle control with the Ortho Evra/Evra transdermal system: the analysis of pooled data. Fertil Steril 2002; 77:S13. 66. Mangan SA, Larsen PG, Hudson S. Overweight teens at increased risk for weight gain while using depot medroxyprogesterone acetate. J Pediatr Adolesc Gynecol 2002; 15:79. 67. Bonny AE, Ziegler J, Harvey R, et al. Weight gain in obese and nonobese adolescent girls initiating depot medroxyprogesterone, oral contraceptive pills, or no hormonal contraceptive method. Arch Pediatr Adolesc Med 2006; 160:40. 68. Luukkainen T, Lähteenmäki P, Toivonen J. Levonorgestrel-releasing intrauterine device. Ann Med 1990; 22:85. 69. Miller RJ, Xanthakos SA, Hillard PJ, Inge TH. Bariatric surgery and adolescent gynecology. Curr Opin Obstet Gynecol 2007; 19:427. 70. Woodard CB. Pregnancy following bariatric surgery. J Perinat Neonatal Nurs 2004; 18:329. Topic 5880 Version 11.0


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GRAPHICS Roux-en-Y gastric bypass

This figure depicts the stomach's appearance after Roux-en-Y gastric bypass, which creates a small stomach pouch by dividing the stomach and attaching it to the small intestine. The pouch is only able to hold about an ounce of food, causing a feeling of fullness after consuming a very small amount; over time, the pouch stretches to hold about one cup. In addition, the body absorbs fewer calories since food bypasses the majority of the stomach as well as the upper small intestine (duodenum). This intestinal arrangement (Roux-enY) seems to cause decreased appetite and improved metabolism by changing the release of various hormones.


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Laparoscopic adjustable gastric band (LAGB)

This figure shows how the stomach will look after lap banding.


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Sleeve gastrectomy

In a sleeve gastrectomy the majority of the greater curvature of the stomach is removed and a tubular stomach is created. The tubular stomach has a small capacity, is resistant to stretching due to the absence of the fundus, and has few ghrelin producing cells (a gut hormone involved in regulating food intake).


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Recommended evaluation of an adolescent considering bariatric surgery Anthropometrics Systolic and diastolic blood pressure Waist circumference Weight Height Tanner Stage (criteria for surgery is Tanner stage 4 or more)

Laboratory testing Fasting lipid profile Fasting insulin and glucose Oral glucose tolerance test Hemoglobin A1C Liver profile TSH

Diagnostic evaluations Polysomnography Echocardiogram Electrocardiogram Urea breath test or endoscopy to exclude helicobacter pylori infection Bone age if needed to assess skeletal maturity (criteria for surgery is attainment of !95 percent of predicted adult height)

Comprehensive psychological evaluation Evaluation by pediatric psychologist or psychiatrist to screen for cognitive and psychiatric disorders, assess emotional maturity, decisional capacity and family support


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Recommended nutritional supplementation after bariatric surgery in adolescents Gastric bypass Standard multivitamin with folate and iron, or prenatal vitamin if female* Vitamin B12 500 micrograms orally daily, or 1000 micrograms intramuscularly monthly Calcium 1200 mg to 1500 mg daily with 800 units vitamin D• Supplemental iron if iron deficient*

Adjustable banding Standard multivitamin with folate and iron* or prenatal vitamin if female* Vitamin B12, iron, calcium with vitamin D as indicated clinically * Additional iron and folate may be necessary in pregnant females. • Calcium citrate may be better absorbed.


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US Medical Eligibility Criteria for Contraceptive Use: Summary of classifications for hormonal contraceptive methods and intrauterine devices Health-care providers can use the summary table as a quick reference guide to the classifications for hormonal contraceptive methods and intrauterine contraception and to co classifications across these methods. See the full appendix for each method for clarifications to the numeric categories, as well as for summaries of the evidence and additional BOX. Categories for classifying hormonal contraceptives and IUDs 1 = A condition for which there is no restriction for the use of the contraceptive method. 2 = A condition for which the advantages of using the method generally outweigh the theoretical or proven risks. 3 = A condition for which the theoretical or proven risks usually outweigh the advantages of using the method. 4 = A condition that represents an unacceptable health risk if the contraceptive method is used.

Condition

COC/P/R

POP

DMPA

Implants

LNG-IUD

Personal characteristics and reproductive history Pregnancy

Not applicable*

Not applicable*

Not applicable*

Not applicable*

4*

4*

Age

Menarche to <40 yrs = 1





Menarch 2

!40 yrs = 2

18-45 yrs = 1

18-45 yrs = 1

18-45 yrs = 1

!20 yrs = 1

!20 yrs

>45 yrs = 1

>45 yrs = 2

>45 yrs = 1

Parity a. Nulliparous

1

1

1

1

2

2

b. Parous

1

1

1

1

1

1

4

1

1

1

i. With other risk factors for VTE (such as age !35 years, previous VTE, thrombophilia, immobility, transfusion at delivery, BMI !30, postpartum hemorrhage, postcesarean delivery, preeclampsia or smoking)

3"

1

1

1

ii. Without other risk factors for VTE

2

1

1

1

1

1

1

1

4

2

2

2

3"

2

2

2

3

2

2

2

i. With other risk factors for VTE (such as age !35 years, previous VTE, thrombophilia, immobility, transfusion at delivery, BMI !30, postpartum hemorrhage, postcesarean delivery, preeclampsia or smoking)

3"

1

1

1

ii. Without other risk factors for VTE

2

1

1

1

2

1

1

1

Postpartum (nonbreastfeeding women) a. <21 days b. 21 days to 42 days

c. >42 days

Postpartum (breastfeeding women #) a. <21 days b. 21 to <30 days i. With other risk factors for VTE (such as age !35 years, previous VTE, thrombophilia, immobility, transfusion at delivery, BMI !30 kg/m2, postpartum hemorrhage, postcesarean delivery, preeclampsia or smoking) ii. Without other risk factors for VTE c. 30-42 days

d. >42 days


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Postpartum (breastfeeding or nonbreastfeeding women, including post-Cesarean section) a. <10 min after delivery of the placenta

2

1

b. 10 min after delivery of the placenta to <4 wks

2

2

c. !4 wks

1

1

d. Puerperal sepsis

4

4

Postabortion a. First trimester

1*

1*

1*

1*

1*

1*

b. Second trimester

1*

1*

1*

1*

2

2

c. Immediate postseptic abortion

1*

1*

1*

1*

4

4

Past ectopic pregnancy

1

2

1

1

1

1

History of pelvic surgery (see postpartum, including Cesarean section)

1

1

1

1

1

1

2

1

1

1

1

1

i. <15 Cigarettes/day

3

1

1

1

1

1

ii. !15 Cigarettes/day

4

1

1

1

1

1

a. !30 kg/m2 BMI

2

1

1

1

1

1

b. Menarche to <18 yrs and !30 kg/m2 BMI

2

1

2

1

1

1

1

1

1

1

1

1

3

1

1

1

1

3/4*

2*

3*

2*

2

1

3*

1*

2*

1*

1

1

Smoking a. Age <35 yrs b. Age !35 yrs

Obesity

History of bariatric surgery§ a. Restrictive procedures: decrease storage capacity of the stomach (vertical banded gastroplasty, laparoscopic adjustable gastric band, laparoscopic sleeve gastrectomy) b. Malabsorptive procedures: decrease absorption of nutrients and calories by shortening the functional length of the small intestine (Roux-en-Y gastric bypass, biliopancreatic diversion)

COCs: 3 P/R: 1

Cardiovascular disease Multiple risk factors for arterial cardiovascular disease (such as older age, smoking, diabetes, and hypertension) Hypertension a. Adequately controlled hypertension

b. Elevated blood pressure levels (properly taken measurements) i. Systolic 140-159 mmHg or diastolic 9099 mmHg

3

1

2

1

1

1

ii. Systolic !160 mmHg or diastolic !100 mmHg§

4

2

3

2

2

1

4

2

3

2

2

1

2

1

1

1

1

1

2

2

2

1

c. Vascular disease History of high blood pressure during pregnancy (where current blood pressure is measurable and normal)

Deep venous thrombosis (DVT)/pulmonary embolism (PE) a. History of DVT/PE, not on anticoagulant therapy i. Higher risk for recurrent DVT/PE ( !1 risk factors)

4

2


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History of estrogenassociated DVT/PE Pregnancyassociated DVT/PE Idiopathic DVT/PE Known thrombophilia, including antiphospholipid syndrome Active cancer (metastatic, on therapy, or within 6 mos after clinical remission), excluding nonmelanoma skin cancer History of recurrent DVT/PE ii. Lower risk for recurrent DVT/PE (no risk factors) b. Acute DVT/PE

3

2

2

2

2

1

4

2

2

2

2

2

c. DVT/PE and established on anticoagulant therapy for at least 3 mos 4*

2

2

2

2

2

3*

2

2

2

2

2

2

1

1

1

1

1

i. With prolonged immobilization

4

2

2

2

2

1

ii. Without prolonged immobilization

2

1

1

1

1

1

f. Minor surgery without immobilization

1

1

1

1

1

1

4*

2*

2*

2*

2*

1*

i. Higher risk for recurrent DVT/PE ( !1 risk factors) Known thrombophilia, including antiphospholipid syndrome Active cancer (metastatic, on therapy, or within 6 mos after clinical remission), excluding nonmelanoma skin cancer History of recurrent DVT/PE ii. Lower risk for recurrent DVT/PE (no risk factors) d. Family history (firstdegree relatives) e. Major surgery

Known thrombogenic mutations§ (eg, factor V Leiden; prothrombin mutation; protein S, protein C, and antithrombin deficiencies)

Superficial venous thrombosis a. Varicose veins

1

1

1

1

1

1

b. Superficial thrombophlebitis

2

1

1

1

1

1

Current and history of ischemic heart disease§ Stroke§ (history of cerebrovascular accident) Known hyperlipidemias

Initiation

Continuation

2

3

Initiation

Continuation

4

2

3

2/3*

2

4

Initiation

Continuation

Initiation

Continuation

2

3

2

3

Initiation

Continuation

3

2

3

2*

2*

1

1

3

1

2

1

2*

2*

1*

1

1

1

Valvular heart disease a. Uncomplicated


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b. Complicated§

4

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1

1

1

1

1

(pulmonary hypertension, risk for atrial fibrillation, history of subacute bacterial endocarditis) Peripartum cardiomyopathy§ a. Normal or mildly impaired cardiac function (New York Heart Association Functional Class I or II: patients with no limitation of activities or patients with slight, mild limita (1) i. <6 mos

4

1

1

1

2

2

ii. !6 mos

3

1

1

1

2

2

4

2

2

2

2

2

b. Moderately or severely impaired cardiac function (New York Heart Association Functional Class III or IV: patients with marked limitation of activity or patients who should be at complete rest) (1) Rheumatic diseases Systemic lupus

Initiation

Continuation

Initiatio

erythematosus§ a. Positive (or unknown) antiphospholipid antibodies

4

3

3

3

3

3

1

b. Severe thrombocytopenia

2

2

3

2

2

2*

3*

c. Immunosuppressive treatment

2

2

2

2

2

2

2

d. None of the above

2

2

2

2

2

2

1

Rheumatoid arthritis

Initiation

Continuation

Initiatio

1

2

a. On immunosuppressive therapy

2

1

2/3*

1

2

b. Not on immunosuppressive therapy

2

1

2

1

1

1

Neurologic conditions Headaches

I ni tiat ion

Co nt in uat io n

I ni tiat ion

Co nt in uat io n

I ni tiat ion

Co nt in uat io n

I ni tiat ion

Co nt in uat io n

I ni tiat ion

Co nt in uat io n

1*

2*

1*

1*

1*

1*

1*

1*

1*

1*

- Age <35 yrs

2*

3*

1*

2*

2*

2*

2*

2*

2*

2*

1*

- Age !35 yrs

3*

4*

1*

2*

2*

2*

2*

2*

2*

2*

1*

4*

4*

2*

3*

2*

3*

2*

3*

2*

3*

a. Non-migrainous (mild or severe)

1*

b. Migraine i. Without aura

ii. With aura (at any age) Epilepsy§

1*

1*

1*

1*

1*

1

1

1*

1*

1*

1*

1*

If on treatment, see Drug interactions section below Depressive disorders Depressive disorders

1*

Reproductive tract infections and disorders Vaginal bleeding patterns

Initiation

Continuation

a. Irregular pattern without heavy bleeding

1

2

2

2

1

1

1

b. Heavy or prolonged bleeding (includes regular and irregular patterns)

1*

2*

2*

2*

1*

2*

2*

Initiation

Continuation

Initiatio

2*

4*

Unexplained vaginal bleeding (suspicious for serious condition) Before evaluation

2*

2*

3*

3*

4*

Endometriosis

1

1

1

1

1

2

Benign ovarian tumors (including cysts)

1

1

1

1

1

1

Severe dysmenorrhea

1

1

1

1

1

2

1

1

1

3

3

Gestational trophoblastic disease a. Decreasing or undetectable $-hCG

1


Página 15 de 19


26/05/12 12:22

levels b. Persistently elevated $-hCG levels or malignant disease §

1

1

1

1

4

4

Cervical ectropion

1

1

1

1

1

1

Cervical intraepithelial neoplasia

2

1

2

2

2

1

Cervical cancer (awaiting treatment)

Initiation

Continuation

Initiatio

2

4

2

1

2

2

4

a. Undiagnosed mass

2*

2*

2*

2*

2

1

b. Benign breast disease

1

1

1

1

1

1

c. Family history of cancer

1

1

1

1

1

1

i. Current

4

4

4

4

4

1

ii. Past and no evidence of current disease for 5 yrs

3

3

3

3

3

1

1

1

1

1

1

1

Breast disease

d. Breast cancer§

Endometrial hyperplasia Endometrial cancer§

Initiation

Continuation

Initiatio

2

4

1

1

1

1

4

Ovarian cancer§

1

1

1

1

1

1

Uterine fibroids

1

1

1

1

2

2

a. Distorted uterine cavity (any congenital or acquired uterine abnormality distorting the uterine cavity in a manner that is incompatible with IUD insertion)

4

4

b. Other abnormalities (including cervical stenosis or cervical lacerations) not distorting the uterine cavity or interfering with IUD insertion

2

2

Anatomical abnormalities

Pelvic inflammatory disease (PID) a. Past PID (assuming no current risk factors of STIs)

Initiation

Continuation

Initiatio

i. With subsequent pregnancy

1

1

1

1

1

1

1

ii. Without subsequent pregnancy

1

1

1

1

2

2

2

1

1

1

1

4

2*

4

Initiation

Continuation

Initiatio

b. Current PID STIs a. Current purulent cervicitis or chlamydial infection or gonorrhea

1

1

1

1

4

2*

4

b. Other STIs (excluding HIV and hepatitis)

1

1

1

1

2

2

2

c. Vaginitis (including Trichomonas vaginalis and bacterial vaginosis)

1

1

1

1

2

2

2

d. Increased risk for STIs

1

1

1

1

2/3*

2

2/3*

Initiation

Continuation

Initiatio

HIV/AIDS

High risk for HIV

1

1

1

1

2

2

2

HIV infection§

1

1

1

1

2

2

2

AIDS§

1*

1*

1*

1*

3

2*

3

2

2

2

Clinically well on ARV therapy

If on treatment, see Drug interactions section below


Página 16 de 19


26/05/12 12:22

Other Infections Schistosomiasis a. Uncomplicated

1

1

1

1

1

1

b. Fibrosis of the liver (if severe, see Cirrhosis) §

1

1

1

1

1

1

Tuberculosis§

Initiation

Continuation

Initiatio

a. Nonpelvic

1*

1*

1*

1*

1

1

1

b. Pelvic

1*

1*

1*

1*

4

3

4

1

1

1

1

1

1

1

1

1

1

1

1

i. Noninsulindependent

2

2

2

2

2

1

ii. Insulin-dependent§

2

2

2

2

2

1

c. Nephropathy/retinopathy/ neuropathy§

3/4*

2

3

2

2

1

d. Other vascular disease or diabetes of >20 yrs' duration §

3/4*

2

3

2

2

1

a. Simple goiter

1

1

1

1

1

1

b. Hyperthyroid

1

1

1

1

1

1

c. Hypothyroid

1

1

1

1

1

1

2/3*

2

2

1

1

1

i. Treated by cholecystectomy

2

2

2

2

2

1

ii. Medically treated

3

2

2

2

2

1

iii. Current

3

2

2

2

2

1

b. Asymptomatic

2

2

2

2

2

1

a. Pregnancy-related

2

1

1

1

1

1

b. Past COC-related

3

2

2

2

2

1

If on treatment, see Drug interactions section below Malaria Endocrine conditions Diabetes a. History of gestational disease b. Nonvascular disease

Thyroid disorders

Gastrointestinal conditions Inflammatory bowel disease (IBD) (ulcerative colitis, Crohn disease) Gallbladder disease a. Symptomatic

History of cholestasis

Viral hepatitis

Initiation

Continuation

a. Acute or flare

3/4*

2

1

1

1

1

1

b. Carrier

1

1

1

1

1

1

1

c. Chronic

1

1

1

1

1

1

1

Cirrhosis a. Mild (compensated)

1

1

1

1

1

1

b. Severe§

4

3

3

3

3

1

i. Focal nodular hyperplasia

2

2

2

2

2

1

ii. Hepatocellular adenoma §

4

3

3

3

3

1

4

3

3

3

3

1

Thalassemia

1

1

1

1

1

2

Sickle cell disease§

2

1

1

1

1

2

(decompensated) Liver tumors a. Benign

b. Malignant§ (hepatoma) Anemias


Página 17 de 19


Iron-deficiency anemia

1

26/05/12 12:22

1

1

1

1

2

Solid organ transplantation Solid organ

Initiation

Continuation

Initiatio

2

3

transplantation§ a. Complicated: graft failure (acute or chronic), rejection, cardiac allograft vasculopathy

4

2

2

2

3

b. Uncomplicated

2*

2

2

2

2

2

Drug interactions Antiretroviral therapy (see appendix M)

Initiation

Continuation

I nitiatio

a. Nucleoside reverse transcriptase inhibitors (NRTIs)

1*

1

1

1

2/3*

2*

2/3*

b. Non-nucleoside reverse transcriptase inhibitors (NNRTIs)

2*

2*

1

2*

2/3*

2*

2/3*

c. Ritonavir-boosted protease inhibitors

3*

3*

1

2*

2/3*

2*

2/3*

a. Certain anticonvulsants (phenytoin, carbamazepine, barbiturates, primidone, topiramate, oxcarbazepine)

3*

3*

1

2*

1

1

b. Lamotrigine

3*

1

1

1

1

1

a. Broad-spectrum antibiotics

1

1

1

1

1

1

b. Antifungals

1

1

1

1

1

1

c. Antiparasitics

1

1

1

1

1

1

d. Rifampicin or rifabutin therapy

3*

3*

1

2*

1

1

Anticonvulsant therapy

Antimicrobial therapy

COC: combined oral contraceptive; P: combined hormonal contraceptive patch; R: combined hormonal vaginal ring; POP: progestin-only pill; DMPA: depot medroxyprogesterone acetate; IUD: intrauterine device; LNG-IUD: levonorgestrel-releasing IUD; Cu-IUD: copper IUD; BMI: body mass index (weight [kg]/height [m 2]); DVT: deep venous thrombosis; VTE: venous thromboembolism; CHC: combined hormonal contraceptive; PE: pulmonary embolism; hCG: human chorionic gonadotropin; PID: pelvic inflammatory disease; STI: sexually transmitted infection; HIV: human immunodeficiency virus; AIDS: acquired immunodeficiency syndrome; NRTI: nucleoside reverse transcriptase inhibitor; NNRTI: non-nucleoside reverse transcriptase. * Consult the appendix for this contraceptive method for a clarification to this classification. " Clarification: For women with other risk factors for VTE, these risk factors might increase the classification to a "4"; for example, smoking, deep venous thrombosis/pulmonary embolism, known thrombogenic mutations, and peripartum cardiomyopathy. # The breastfeeding recommendations are divided by month in US Medical Eligibility Criteria for Contraceptive Use, 2010 . They have been divided by days for purposes of integration with the postpartum recommendations. § Condition that exposes a woman to increased risk as a result of unintended pregnancy. Updated information reproduced from: Update to CDC's U.S. Medical Eligibility Criteria for Contraceptive Use, 2010: Revised Recommendations for the Use of Contraceptive Methods During the Postpartum Period. MMWR Morb Mortal Wkly Rep 2011; 60:878. Original table published in: US Medical Eligibility Criteria for Contraceptive Use 2010, with data adapted from the World Health Organization Medical Eligibility Criteria for Contraceptive Use, 4th edition.


Página 18 de 19


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Surgical Management of Severe Obesity in Adolescents

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