1、An Overview of Bariatric Surgery,Kristin Dermody Angela Illing May 23, 2005,THE OBESITY EPIDEMIC,A Quick Background of Obesity,Derived from the Latin word obesus “to devour” Definition: having a very high amount of body fat in relation to lean body mass Classifications using Body Mass Index (BMI),BM
2、I Categories,A BMI of: Classifies one as: 18.5 Underweight 18.5-24.9 Normal weight 25-29.9 Overweight 30-34.9 Obesity Class I 35-39.9 Obesity Class II 40-49.9 Obesity Class III 50 and above Super Obesity,Obesity is a BIG problem,1.7 billion worldwide are overweight or obese The US has a higher perce
3、ntage of overweight and obese people than any country in the world And the numbers are growing,US Incidence of Obesity,Approximately 2/3 of the United States population is overweight. Of those, almost 50% are obese. In total, approximately 5% of the US population is morbidly obese Alarmingly, the BM
4、I subgroups growing the most quickly are 35 or higher and 40 or higher.,Massachusetts: Not-so-Phat Facts,55% of Mass adults overweight or obese* Of these obese adults* 18% non-Hispanic white 30% non-Hispanic black 22% Hispanic 24% of Mass high school students overweight or at risk of becoming overwe
5、ight Obesity rate among Mass adults by 81% from 1990 to 2000*,*CDC BRFSS, 2002; *CDC YRBSS, 2003,History of Obesity,1985,Potential Consequences of Obesity,Obesity is associated with a rise in many comorbid conditions, including: Type 2 Diabetes Hyperlipidemia Hypertension Obstructive Sleep Apnea Hea
6、rt Disease Stroke Asthma Back and lower extremity weight-bearing degenerative problems Cancer Depression AND MORE!,CVD & Obesity,Fact: Obesity contributes to these co-morbid conditions, however Recent JAMA article by Gregg et al* suggests CVD risk factors across all BMI groups over past 40 years Sug
7、gest: Overweight not quite as bad as it once was, considering other factors:Risk r/t awareness, aggressive identification, pharmacological tx of high chol, HTN. Note: Obese persons still have risk factor levels vslean persons.,Gregg EW, et al. Secular Trends in Cardiovascular Disease Risk Factors Ac
8、cording to Body Mass Index in US Adults. JAMA, 2005:293:1863-1874,Impact of Obesity,These comorbid conditions are together responsible for more than 2.5 million deaths per year worldwide*.This is in addition to billions of dollars in healthcare costs and lost productivity.,*World Health Organization
9、, World Health Report 2002,Obesity and Life Expectancy,Recent NEJM article* If current rates of obesity are left unchecked, the current generation of American children will be the first in two centuries to have a shorter life expectancy than their parents.The life-shortening impact of obesity (curre
10、ntly estimated at 1/3 to year) could rise to 2 to 5 years, or more, as obese children spend more years at risk for comorbid conditions.,Olshansky SJ, et al. A Potential Decline in Life Expectancy in the United States in the 21st Century. NEJM, 352(11):1138-1145, 2005,Obesity and Life Expectancy,The
11、morbidly obese are perhaps the worst off Compared to a normal-weight person, a 25-year-old morbidly obese man has a 22% reduction in expected remaining lifespan. This is an approximate loss of 12 YEARS! This number will also likely grow if the ever-expanding numbers of currently obese children conti
12、nue as obese adults,TREATING OBESITY,Weight Loss Strategies,Diet therapy Increased Physical Activity Pharmacotherapy (e.g., Orlistat, Meridia) Behavioral Therapy Hypnosis Any combination of the above,Bariatric Surgery,An effective treatment for combating obesity,Bariatric Surgery,1991: NIH establish
13、es guidelines for the surgical therapy of morbid obesity Recommends BMI criteria BMI 40 BMI 35 + significant comorbidities This therapy now referred to as Bariatric Surgery,Types of Bariatric Surgery,Purely Restrictive Gastric Balloons (not approved for use in USA) Vertical-banded gastroplasty Gastr
14、ic adjustable banding (BWH) Restrictive Malabsorptive Short-limb/Roux-en-Y gastric bypass (BWH) Long-limb/distal Roux-en-Y gastric bypass Malabsorptive Restrictive Biliopancreatic diversion (BPD) BPD with duodenal switch Very long limb Roux-en-Y gastric bypassPurely Malabsorptive Jejunoilieal bypass
15、 Jejunocolonic bypass,A Brief History of Bariatric Surgery,First developed: Pts with short bowel syndrome weight loss First weight loss surgeries (ca. 1950s) Intestinal bypass Low-risk surgically BUT many patients developed serious and often fatal complications Biliopancreatic diversion Effective BU
16、T with high risk and many complications,Evolution of the Roux-en-Y,Gastric partitioning (Roux-en-Y GBP) Based on observations of weight loss in pts receiving subtotal gastric resections for other conditions 1967 First performed Continues to be studied and refined,Roux-en-Y,Open* 2 hour procedure 3 d
17、ays in-house 4 weeks Return to work 60-70% EBW loss 2 yrs 0.5-1.0% Risk of Death Dumping Syndrome Laparoscopic* 2-4 hour procedure 3 days in-house 2-3 weeks Return to work 60-70% EBW loss 2yrs 0.5-1.0% Risk of Death Dumping Syndrome,* Data based on averages.,Evolution of Gastric Banding,1970s Altern
18、ative to Roux-en-Y in Europe & Scandinavia 1980s Adjustable silicone band developed 1990s Laproscopic techniques for placement developed,Gastric Banding,Adjustable Lap Band 1 hr procedure 1 day in-house 1 wk Return to work 40-45% EBW loss 2 yrs 0.1% Risk of Death Self-sabotage easier,Who Gets Bariat
19、ric Surgery?,Gender 19% Males 72.6% Females (8% gender not reported) Age Mean age 39 years Range 16-64 years BMI Mean BMI 46.9 Range 32.3-68.8,Buchwald H, et al. Bariatric Surgery: A Systematic Review and Meta-analysis. JAMA, 14:1724-37, 2004,Medical Nutrition Therapy and The Post-op Bariatric Patie
20、nt,Post-Surgical Nutrition,Balanced/healthy diet Liquids to pureed to soft to solid* High nutrient density, quality Modified in lactose, fat, sugar Adequate fluid Portion Control Meal Periods/Eating time MVI/MIN Ca (1200mg/d) + D (10-20mg) Folate (800-1000mcg) +B12 Iron (45-100mg elemental pre-menst
21、rual) Vitamin C (75-100mg) Thiamin Self-monitoring Eating triggers/behaviors Exercise,* Time line may vary among institutions,Post-Op Roux-En-Y Diet,Stage One (1 day) Water and clear liquids Non-caloric, non-carbonated, non-caffeinated liquids Fluid goal: 28-32oz/d Stage Two (14 days) High protein,
22、low sugar beverages Fluid goal: 56oz Protein goal: 60-70g/d Chewable MVI + Ca,Post-Op Roux-En-Y Diet,Stage Three (4 weeks) 5 2oz servings diced protein Fluid goal: 56oz Protein goal: 60-70g Chewable MVI + Ca Stage Four (4 months) 3 meals, 2 snacks 850kcal/d Fluid goal: 56oz Protein goal: 60-70g Chew
23、able MVI + Ca,Stage Five (ongoing) Regular Meals 1200-1500kcal Fluid & Protein goals: same as above,Post-op Lap Band Diet,Stage One (1 day) Water & Clear Liquids Non-carbonated, non-caffeinated, non-caloric liquids Fluid goal: 28-32oz/d Stage Two (14 days) 5-8oz servings of High Protein, low sugar B
24、everage Fluid goal: 56oz Protein goal: 50-60g Chewable MVI + Ca,Post-op Lap Band Diet,Stage Three (14 days) Pureed Foods, Semi solids 2 small meals, 3 snacks Fluid goal: 56oz Protein goal: 50-60g Chewable MVI + Ca Stage Four (ongoing) Regular meals: 3 meals,2 snacks (1000-1200) Fluid goal: 56oz Prot
25、ein goal: 50-60g Chewable MVI + Ca,Post-Surgical Nutrition & Exercise,RD seen frequently 1m 3m 6m 1yr Exercise No heavy lifting or exercise 6-8wks post-op Walking daily OK, encouraged After cleared, strength training important to help skin stretch back Helps with weight loss in the long run,When Sur
26、gery and Follow-Up Go Well,Efficacy of Bariatric Surgery for Weight Loss,Mean percentage excess weight loss: 61.2% - All Patients 47.5% - Gastric Banding 61.6% - Gastric Bypass 68.2% - Gastroplasty 70.1% - BPD or duodenal switch,*Buchwald H, et al. Bariatric Surgery: A Systematic Review and Meta-ana
27、lysis. JAMA, 14:1724-37, 2004,Human body regulates nutrient intake over time by secreting hormones Over 40 hormones play a role in regulation of feeding.,Roux-en-Y: Metabolic Sequelae,Roux-en-Y: Metabolic Sequelae,Two types: Satiety hormones Short-term Help regulate meal size; daily intake Secretion
28、 decreases meal size; reduces time to stop Includes (among others) cholecystokinin, amylin, glucagon-like-peptide 1 (GLP-1), enterostatin, and bombesin Adiposity hormones Long-term Related to energy stores Secretion delays onset of beginning of meal Includes insulin, leptin,Roux-en-Y: Metabolic Sequ
29、elae,Also of note is ghrelin, the endogenous ligand for the growth hormone secretagogue receptor Mostly secreted in the fundus of the stomach (part bypassed in RYGB) Contrary to satiety hormones, ghrelin is orexigenic i.e., increases appetite (fasting increases levels),Roux-en-Y: Metabolic Sequelae,
30、Plasma ghrelin normally increases after non-surgical weight loss This supports long-term weight homeostasis Proportional to lean body mass Initial report showed circulating plasma ghrelin greatly decreased in pts s/p RYGB Past theory: exclusion of the fundus of the stomach responsible for lower ghre
31、lin levels (and therefore greater weight loss),Studies since then have shown no change or increase in ghrelin after bypass Additionally, found that post-pyloric nutrient stimulation vs stomach distention responsible for changes in ghrelin levels Does not support idea that bypassing stomach fundus re
32、sponsible for changes, if any, in ghrelin levels Overall, still not well understood,Roux-en-Y: Metabolic Sequelae,Strader AD, et al. Gastrointestinal Hormones and Food Intake. Gastroenterology, 128:175-91, 2005,Roux-en-Y: Metabolic Sequelae,Further investigation is needed, but thought that one reaso
33、n certain types (i.e., RYGB) of bariatric surgery are successful at reducing food intake and causing weight loss may be related to enhanced secretion of satiety signals (ghrelin or others).,Effect on Comorbid Conditions,Diabetes 76.8% - Completely resolved 86.0% - Resolved or improved Hyperlipidemia
34、 70% - Improved HTN 61.7% - Resolved 85.7% - Resolved or improved Obstructive Sleep Apnea 83.6% - Resolved 85.7% - Resolved or improved,Buchwald H, et al. Bariatric Surgery: A Systematic Review and Meta-analysis. JAMA, 14:1724-37, 2004,Metabolic Changes and Diabetes,Many metabolic changes contribute
35、 to improvement and/or resolution of DM s/p bariatric surgery: Recovery of acute insulin response Decreases of inflammatory indicators (C-reactive protein and interleukin 6) Improvement in insulin sensitivity correlated w/increases in plasma adiponectin Changes in the enteroglucagon response to gluc
36、ose Reduction in ghrelin levels (s/p RYGB, but not banding) Improvement in beta cell function (s/p banding, but not RYGP),Effect on Quality of Life,Studies show overall QOL greatly improved Relief from comorbidities Improved appearance Perception of improved: Well-being Social function Body self-ima
37、ge Self confidence Ability to interact with others Increased time spent in recreational and physical activities Enhanced productivity Increased economic opportunities Often new employment More lucrative employment,PROBLEMS AND COMPLICATIONS of Bariatric Surgery,Possible Complications of Bariatric Su
38、rgery,General Complications Pulmonary embolism Incisional hernia Gallstone formation Major wound infection and seroma Abdominal fluid collection Subphrenic abscess Peritonitis,Procedure-Specific Complications (RYGB),Anastomotic or staple-line leak Acute gastric distention Staple-line disruption Stom
39、al stenosis Stomal ulceration Small-bowel obstruction Occlusion of Roux limb,Intermediate Complications,Wound Infection Intra-abdominal bleed Gastric remnant necrosis Ischemic Roux-limb Internal hernia,Long-Term GI Complications,Nausea Constipation Abdominal pain Marginal ulcers Incisional hernias V
40、omiting Diarrhea Gallstones Gastritis Intestinal Obstructions,Incidence of Complications,Operative mortality ( 30 days): 0.1% for Purely Restrictive Procedures 0.5% for Gastric Bypass 1.1% for BPD or Duodenal Switch,Long-Term Nutrition Complications,Malnutrition Vitamin and mineral deficiencies Weig
41、ht loss failure Dehydration Anemia Dumping Syndrome Hair loss Dry skin,Risk of Vitamin and Mineral Deficiencies Post-op,Calcium and Vitamin D Reduced absorption d/t bypassed duodenum, proximal jejunum (R-en-Y) Life-long supplements mandatory Iron Absorption decreased d/t decreased contact of food wi
42、th gastric acid; reduced conversion of iron from ferrous to ferric form (MVI) Vitamin B12 Absorption decreased d/t decreased contact with intrinsic factor 60% of patients require long term supplementation of B12 Thiamine Connection to Wernickes syndrome Cases not well documented,Post-Surgical Eating
43、 Avoidance Disorder (PSEAD),De novo synthesis of eating disorders post-GBP No history pre-operatively Do not fit criteria for AN, BN, or BED Classify now as EDNOS Characteristics consistent enough to suggest new eating disorder,Post-Surgical Eating Avoidance Disorder (PSEAD),Proposed Criteria: Previ
44、ous h/o morbid obesity followed by bariatric surgery over the last 2 years Higher speed of weight loss than the average Use of purgative strategies or excessive reduction of food intake, related or not related to binge eating episodes,Post-Surgical Eating Avoidance Disorder (PSEAD),Proposed Criteria
45、: Reaction of extreme anxiety +/or negative attitude when nutritional correction introduced Intense fear of going back to pre-op wt Does not accept attempts to interrupt the wt loss Denies doing something exaggerated that account for loss Perceives a positive return with wt loss in spite of evidence
46、 to the contrary,Post-Surgical Eating Avoidance Disorder (PSEAD),Proposed Criteria: Body image dissatisfaction or distortion Follow-up nutritional tests (such as laboratory tests) alterations that are significant and/or not in line with the surgical technique, maintained for more than 2 months after
47、 initial interventions Exclude AN and BN, according to DSM IV Exclude Simple Phobias (I.e., Food or Choking Phobia) according to DSM IV Exclude organic causes as the most probable factor for excessive weight loss,Segal et al. Post-Surgical Refusal to Eat: Anorexia Nervosa, Bulimia Nervosa or a New E
48、ating Disorder? A Case Series. Obes Surg, 14:353-359, 2004,Post-Surgical Eating Avoidance Disorder (PSEAD),A proposed ED classification Not yet part of the DSM IV,ED: Contraindication for GBP?,Pt with h/o of AN or BN likely not a good surgical candidate Pt at high risk for malnutrition after surgery
49、 Some with h/o ED receive surgery Important to screen carefully before AND monitor closely post-op to prevent relapse of disorder, malnutrition.,Long Term Impact & Future Directions,Long-Term Changes: Weight Regain,One study of 342 gastric bypass pts showed excellent long-term weight maintenance: % weight loss at: 1 year (89%) 2 years (87%) 5 years (70%) 10 years (75%) However, potential for pouch stretch, self-sabotage, etc. leading to weight regain over time. Surgery relatively new, will have to wait and reanalyze data in a few years.,
