Bradley 1

Metabolic SurgeryDavid Bradley, MD, MS

Objectives

Review the current surgical treatment options and their effectiveness possible side effects andand their effectiveness, possible side effects and complications

Identify appropriate surgical candidates and be able to counsel patients about the importance of compliance with the post-operative regimen

Discuss follow-up care and long-term p gmanagement of the post-bariatric surgical patient

2

Bradley 2

The Obesity Epidemic

69.2% of adults are overweight or obese (2010)

$200 billion spent in 2005 to treat the $200 billion spent in 2005 to treat the medical consequences of overweight and obesity

Obese individuals are more than twice as likely to take sick leave and three times as likely to become disabled

Up to 365,000 deaths/year attributed to obesity

Centers for Disease Control and Prevention. http://www.cdc.gov/nchs/fastats/overwt.htmFlegal KM, Graubard BI, Williamson DF, Gail MH. Excess deaths associated with underweight, overweight, and obesity. JAMA. 2005;293(15):1861

Mokdad AH, Marks JS, Stroup DF, Gerberding JL. Correction: actual causes of death in the United States, 2000. JAMA. 2005;293(3):293.

Health Burden

Whitlock G, Lewington S, Sherliker P, et al. Body-mass index and cause-specific mortality in 900,000 adults: collaborative analyses of 57 prospective studies. Lancet 2009; 373:1083.

Bradley 3

Health Burden Type 2 diabetes

Hypertension

Cardio asc lar disease Cardiovascular disease

Stroke

Dyslipidemias

Osteoarthritis

Cancers

Sl Sleep apnea

Gall bladder disease

Female infertility

Psychological issues

Health Burden

Bradley 4

Therapeutic Options More than two-thirds of adults in the US are either trying to

lose weight or to maintain their weight; however, only 20% are both eating fewer calories and engaging in 150 min of physical activity/weekphysical activity/week Popular diets: reduce caloric intake by restricting certain foods and

limiting portions, i.e. by counting calories, fat or carbs Medically supervised diets

Very Low Calorie Diets (VLCD)

Liquid Fasts

Referral to a nutritionist or dietician Exercise regimens g Medications (sibutramine, orlistat, locaserin,

phentermine/topiramate) Cognitive Behavioral Training Bariatric Surgery

Maynard LM, et al. Secular trends in desired weight of adults. Int J Obes2006;30:1375.

Bariatric Surgery

Number of procedures performed has increased 25-fold

14 000 i 1993 14,000 in 1993

140,000 in 2004

> 200,000 in 2005

> 300,000 in 2007

> 340,000 in 2011

Bradley 5

Bariatric SurgeryEvidenced Based Recommendations Cochrane Review (2009):

Surgery results in greater weight loss than conventional treatment in people with BMI greater than 30 as well as those with more severe obesity.

S l d t i t i lit f lif d b it l t d Surgery leads to some improvements in quality of life and obesity related diseases such as hypertension and diabetes.

Certain procedures produce greater weight loss, but data are limited. The evidence on safety is even less clear. Due to limited evidence and poor quality of the trials, caution is required when interpreting comparative safety and effectiveness.

IDF (2011):

Bariatric surgery is an appropriate treatment for people with T2D and obesity not achieving treatment targets with medical therapy

Surgery should be an accepted option in people with T2D and BMI >35

Surgery should be considered as an alternative treatment option in patients with BMI 30-35 whose diabetes is uncontrolled

Available evidence indicates that bariatric surgery for obese patients with T2DM is cost effective and safe

Colquitt JL, Picot J, Loveman E, Clegg AJ. Surgery for obesity. Cochrane Database Syst Rev. 2009 Apr 15;(2).

Dixon JB, et al. Bariatric Surgery: an IDF statement for obese Type 2 Diabetes. Diabetic Med . 2011.

Indications

Body Mass Index of ≥ 40 kg per m2 or

Body Mass Index of 35 to 39.9 kg per m2 with one or more significant comorbities: Type 2 diabetes, Obstructive sleep apnea, Coronary artery disease,

Debilitating arthritis, NASH, GERD

Online BMI calculator available @ http://familydoctor.org

Body Mass Index 30 to 34.9 kg per m2 with: Uncontrollable T2DM

Metabolic Syndrome

Gastrointestinal surgery for severe obesity. Consensus Statement 1991;9:1-20. Available online at http://consensus .nih.gov/1991/1991GISurgeryobesity084html.htm.

Critical assessment of the current guidelines for the management and treatment of morbidly obese patients. J EndocrinolInvest. 2007 Nov;30(10):844-52. American Bariatric Society 2004

Bradley 6

Indications (continued)

Previous failed weight loss attempts using an integrated weight loss program including: Dietary modification Dietary modification Behavioral support Appropriate exercise

Appropriate motivation and psychological stability to understand risks and benefits of the procedure

The commitment to lifelong postoperative lifestyle changes and medical surveillance

Gastrointestinal surgery for severe obesity. Consensus Statement 1991;9:1-20. Available online at http://consensus .nih.gov/1991/1991GISurgeryobesity084html.htm.

Contraindications

Poor surgical candidates – inadequate cardiopulmonary reserve drug or alcoholcardiopulmonary reserve, drug or alcohol dependency, impaired intellectual capacity

Unable or unwilling to comply with post-op lifestyle changes, diet, supplementation, f/u

Unstable psychiatric illness or eating disorders

Uncontrolled coagulation problems or cannot be Uncontrolled coagulation problems or cannot be removed from coagulation therapy

For Lap Band – Intra-abdominal adhesions or potential for inadequate pneumoperitoneum

Bradley 7

What are the procedures available for weight loss?

The Malabsorptive Procedures Bypass a large amount of intestine and weight Bypass a large amount of intestine and weight

loss is achieved by: Decreasing small bowel absorptive surface area,

and/or Diversion of biliopancreatic secretions that assist

absorption

The Restrictive Procedures The Restrictive Procedures Restrict the size of the stomach which achieves

weight loss by limiting caloric intake.

Surgical Options

Gastric restriction: Vertical Banded Gastroplasty (VBG)

Sl G t t (SG) Sleeve Gastrectomy (SG) Adjustable gastric banding (AGB)

Malabsorption: Jejunoileal bypass (JIB) Duodenal Switch (DS)

Combined Gastric restriction and Intestinal malabsorption:malabsorption: Roux-en-Y gastric bypass (RYGB) Biliopancreatic Diversion with Duodenal Switch (BPD-DS)

Bradley 8

Buchwald H and Oien D. Metabolic/Bariatric Surgery Worldwide 2011. Obes Surg 2013 23;427-436

The Restrictive ProceduresLap-Band

Pure Restrictive Mechanism

Requires Frequent Surgical Followup Monthly to Every 6 weeks

Requires Significant Dietary Changes

No Malabsorption Risk

R iblReversible

Low Risk and Lowest mortality (0 - 0.5%)

Outpatient Surgery

Bradley 9

The Restrictive ProceduresSleeve Gastrectomy

Permanent Partial GastrectomyR ti f b d f t h•Resection of body of stomach

•Resection of fundus of stomach•Resection of Antrum of stomach

Weight loss mechanisms:•Decreased caloric intake•Increased levels of GLP-1 andIncreased levels of GLP 1 and PYY which stimulate satiety

•Concerns over long-term recurrence of T2D, weight regain

Combined ProceduresGastric Bypass

Creates a small Gastric pouch (<30 mL)

Creates a short Roux Limb (75 – 150 cm in length). Increasing Roux limb length can increase malabsorption.

Combined Procedure: Primarily restrictive Small Malabsorptive limb Restrictive gastric pouch

Difficult to Reverse

W i ht l h iWeight loss mechanisms: Reduce caloric intake Increased levels of GLP-1, PYY, and

CCK which creates an anorectic state and induces satiety

? Reduced ghrelin levels

Bradley 10

Combined ProcedureBPD with Duodenal Switch

Fat Malabsorption Primary Mechanism

Malnutrition an issue Fat Soluble Vitamins Protein malnutrition

Frequent foul smelling stools Up to seven per day

Hepatotoxicityp y Elevated liver enzymes Potential for Liver Failure

Hypoalbuminemia

Hypoproteinemia

Investigational Procedures

Mini-gastric bypass Division of stomach and Pouch anastomosed to

jejunum

Excess weight loss ~50% at 18 monthsExcess weight loss 50% at 18 months

Limited long-term data and higher rates of bile reflux

Intragastric balloon Soft, saline-filled balloon that restricts for 6 months

~33% excess weight loss

Not available in US

Endoscopic gastrointestinal bypass devices Barrier device deployed to prevent luminal contacts

from absorption in SI (EndoBarrier, ValenTx)

Placement failure in 13%

High rates of removal due to patient complaints, sleeve migration, and obstruction

Mean weight loss 10-20%

Bradley 11

There is no evidence based medical approach for procedure selectionapproach for procedure selection

Available prospective data are often of short duration

Potential genetic or biomarkers are limited by clinical utility, sensitivity and specificity

Neff et al. Bariatric Surgery: the challenges with candidate selection, individualizing treatment and clinical outcomes. BMC Medicine 2013;11:8.

Short Term Outcomes

Rate of excess body weight loss RYGB or SG: Occurs rapidly in the first few months (10-15

lb/mo), slows down after (5-7 lb/mo), and reaches a plateau at ~1 ½ years (100-120 lb total)at 1 ½ years (100 120 lb total)

AGB: Occurs more slowly (4 lb/mo) with plateau at 2 years

Operative procedure Excess weight loss (percent) Time until weight stabilization (years)Gastric bypass 60 to 85 1 to 1.5

Adjustable gastric band 45 to 55 2

Buchwald H, Avidor Y, Braunwald E, et al. Bariatric surgery: a systematic review and meta-analysis. JAMA 2004; 292:1724.Ballantyne GH. Measuring outcomes following bariatric surgery: weight loss parameters, improvement in co-morbid conditions,

change in quality of life and patient satisfaction. Obes Surg 2003; 13:954.

j g 5 55Sleeve gastrectomy 55 to 80 1 to 1.5

Bradley 12

Short Term Outcomes

Hypertension*

ACS-BSCN: Remission of HTN at 1 year in 79% of RYGB, 68% SG, 44% AGB

Dyslipidemia*

Total Cholesterol ↓ by 16%, TG by 63%, LDL by 31%↓ y , y , y

60-100% of patients no longer require lipid lowering medications after RYGB

May be less improvement with AGB and SG

OSA

79% remission with RYGB, 77% with AGB and 86% with SG

Other studies have shown weight loss associated improvements

GERD

70% improvement at 1 year after RYGB and reduced adenocarcinoma of the esophagus – Should be procedure of choiceesophagus Should be procedure of choice

SG and AGB may be less efficacious and may have worsening

Infertility

70% of women who were infertile prior to procedure, irregardless of procedure, achieve successful pregnancy

No controlled prospective data on male fertility

Short Term Outcomes – T2D

Dixon (JAMA 2008) 73% of patients undergoing LAGB and 13% in medical

and lifestyle group achieved T2DM remission.

Schauer (NEJM 2012) 42% after RYGB and 37% after LSG compared to 12% in

intensive medical therapy and lifestyle group achieved T2DM remission (A1c<6% without diabetes medications)

Mingrone (NEJM 2012) 95% after BPD and 75% after RYGB compared to 0%

with conventional medical therapy achieved T2DMwith conventional medical therapy achieved T2DM remission (FPG <100, A1c <6.5% without diabetes medications).

Bradley 13

Short Term Outcomes – T2D

Ahn SM, Pomp A, Rubino F. Metabolic surgery for type 2 diabetes. Ann N Y Acad Sci. 2010 Nov;1212:E37-45

Effect of LAGB and RYGB Surgery on Insulin Sensitivity

Bradley D, Conte C, Mittendorfer B, Eagon C, Varela JE, Fabbrini E, Gastaldelli A, Chambers KT, Su X, Okunade A, Patterson BW, Klein S. Effects of gastric bypass and adjustable gastric banding on glucose homeostasis. 2012. Journal

Clinical Investigation vol. 112.

Bradley 14

Predictors of Diabetes Remission Jurowich, et al.

Younger age at time of surgery, lower preoperative insulin dose, lower number of oral antidiabetic medications, shorter duration of diabetes predicted a higher rate of remission

Surgery that bypasses the upper GI tract (RYGB) had higher rate of remission than LAGB Remission was independent of BMI or degree of weight loss

Hall, et al. A1c <10% and T2DM <10 years predicted higher rate of remission

Huang, et al. Higher BMI, younger age, shorter duration of DM higher rate

Hamza, et al. Younger age, %EBWL predictive higher rate

Nannipieri, et al.p , Beta cell function improved greater in remitters

Lee, et al. Higher C-peptide levels predict greater remission

Jurowich C, Thalheimer A, Hartmann D, Bender G, Seyfried F, Germer CT, and Wichelmann C. Improvement of type 2 diabetes mellitus (T2DM) after bariatric surgery--who fails in the early postoperative course? Obes Surg. 2012;22(10):1521-6Hall TC, Pellen MG, Sedman PC, and Jain PK. Preoperative factors predicting remission of type 2 diabetes mellitus after Roux-en-Y gastric bypass surgery for obesity. Obes Surg.2010;20(9):1245-50.Hamza N, Abbas MH, Darwish A, Shafeek Z, New J, and Ammori BJ. Predictors of remission of type 2 diabetes mellitus after laparoscopic gastric banding and bypass. Surg Obes Relat Dis.2011;7(6):691-6.Huang CK, Shabbir A, Lo CH, Tai CM, Chen YS, and Houng JY. Laparoscopic Roux-en-Y gastric bypass for the treatment of type II diabetes mellitus in Chinese patients with body mass index of 25-35. Obes Surg. 2011;21(9):1344-9.

Long Term Outcomes Brethauer et al. (2013)

217 patients with at least 5 year F/U (median 6 yrs): 162 RYGB; 32 AGB; 23 SG patients

T2D recurrence rates:

RYGB 17%

SG 38%

AGB 33%

Shorter duration of T2DM and higher long-term % EBWL predicted long-term remission

Weight regain was associated with recurrence

Brethauer, et al. Can Diabetes be Surgically Cured? Ann Surg 2013 Oct;258(4):628-36.

Bradley 15

Long Term Outcomes

Swedish Obese Subjects (SOS) Trial

Sjostrom L. Review of the key results from the Swedish Obese Subjects (SOS) trial. J Int Med. 2013;273:219-234.

Long Term Outcomes

Bradley 16

Complications

30 day mortality CABG 3.5% AAA repair 3 9%AAA repair 3.9% Pancreatic resection 8.3% Bariatric Surgery <1%

Higher mortality with older age (4.8% over age 65), male gender, super obesity, chronic disease, low-volume surgeons, and open surgery

R d i i t 5% d ti t 2% Readmission rate 5% and reoperation rate 2%

Complications

LRYGB LSG LAGB30‐d mortality (%) 0.14 0.11 0.05

1‐y mortality (%) 0.34 0.21 0.08

30‐d morbidity (%) 5.91 5.61 1.44

30‐d readmission (%) 6.47 5.4 1.71

        Morbidity and mortality associated with LRYGB,  LSG, and LAGB from the ACS‐BSCN dataset

More than one serious complication AGB 0.9%, SG 2.3%, RYGB 3.3%

One or more complication AGB 4.62%, SG10.84%,RYGB 14.87%

Operating Time:

30‐d reoperation/intervention(%) 5.02 2.97 0.92

SG 106.5 (range 66-127) min RYGB 132.2 (range 94-186) min

Hutter MM, Schirmer BD, Jones DB, et al. First report from the American College of Surgeons Bariatric Surgery Center Network: laparoscopic sleeve gastrectomy has morbidity and effectiveness positioned between the band and the bypass. Ann Surg 2011;254(3):410–20 J.F. Finks, K.L. Kole, P.R. Yenumula et al. Predicting risk for serious complications with bariatric surgery: results from the Michigan Bariatric Surgery CollaborativeAnnSurg, 254 (4) (2011), pp. 633–640E.J. DeMaria, V. Pate, M. Warthen et al. Baseline data from American Society for Metabolic and Bariatric Surgery-designated Bariatric Surgery Centers of Excellence using the Bariatric Outcomes Longitudinal Database Surg Obes Relat Dis, 6 (4) (2010), pp. 347–355Trastulli S, et al. Laparoscopic sleeve gastrectomy compared with other bariatric surgical procedures: a systematic review of randomized trials. Surg for Obes RelDiseases. 9 (2013) 816-830.

Bradley 17

Life-Threatening Complications80% of deaths in the first 30 days are due to:

Pulmonary embolism (0.4%) and Venous Thromboembolism Risk factors

BMI ≥ 60 kg/m2

Chronic lower extremity edema Obstructive sleep apnea Truncal obesity H/O pulmonary embolism BPD surgeryg y

Anastomotic leaks

Respiratory failure

Geerts, W.H., Pineo, g.F., Heit, J.A. et al. (2004). Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and

Thrombolytic Therapy. Chest, 126(3 suppl), S338-400.

Life-Threatening Complications Anastomotic leaks (0.8-6%) – Signs and

Symptoms Can occur in RYGB, SG, or BPD w or w/o DS Sustained tachycardia severe abdominal pain fever Sustained tachycardia, severe abdominal pain, fever,

rigors, hypotension Respiratory failure and sepsis

Work-up: UGI or CT scan with contrast – May be negative

Urgent surgical consultation

Exploratory surgery if equivocal signs “Leak Until Proven Otherwise” post op day 1-14

Identify complications early and educate patients about reporting symptoms

Bradley 18

RYGB Complications Bleeding (Significant in 0.4-4%)

Wound infections (3-4%) - Decreased by preoperative antibiotics

Stomal stenosis/Anastomatic strictures (6-20%) Nausea, Vomiting, Inability to advance diet Usually requires EGD and dilation

Marginal ulceration (0.6-16%) near gastrojejunostomy Usually ischemic but can be secondary to excess acid production PPI (Prevacid Solutab), Carafate suspension

Cholelithiasis (upwards of 38%)

Short Bowel Syndrome (~5%)

Internal Hernias (0.4-5.5%) – 38% in BPD-DSInternal Hernias (0.4 5.5%) 38% in BPD DS

Dumping Syndrome (50%) after high glycemic meals Early (within 15 minutes) - abd pain, diarrhea, nausea from rapid

emptying of food into si Late (2-3 hours later) Insulin response leading to hypoglycemia –

dizziness, diaphoresis, tremor

Noninsulinoma pancreatogenous hypoglycemia syndrome from beta cell hypertrophy and possibly GLP-1

AGB Complications

Pouch Dilation (11%)

Band Erosion (7%) Band Erosion (7%)

Port Infection (0.3-9%)

Band slippage or prolapse (1.4-14%)

Stomal Obstruction (up to 14%)

Port malfunction (0 4 7%) Port malfunction (0.4-7%)

Esophageal Dilatation (10%)

Bradley 19

SG Complications

Bleeding

Stenosis – requires endoscopic dilatation

Gastric leaks (5.3%)

Worsening of GERD

Lack of long-term data

Long-Term Complications

Loose stools and diarrhea More common after BPD and RYGB (50-(

60%)

Constipation More common after AGB (39%)

Think Biliary Dyskinesia or Symptomatic Cholelithiasis Up to 50% due to rapid weight loss Consider prophylactic cholecystectomy at

the time of surgery Consider bile salt therapy – Daily for 6

months post op

Bradley 20

Long-Term Complications Metabolic and Nutritional Derangements

Mechanisms

Insufficient intake d/t dietary restrictions and food intolerance (meat, milk, fiber)

The exclusion of the stomach’s inferior part results in a decreased secretion of gastric acid, sometimes required to absorb vitamins and minerals (B12 and iron).

D d j j l l b ti l t d t th h t i it Th d d i th i b ti it f Duodeno-jejunal malabsorption related to the short-circuit. The duodenum is the main absorption site for calcium, iron and vitamin B1 (thiamin).

Asynergia occurs between the bolus and the bilio-pancreatic secretions in the common portion of the intestine.

Micronutrient and mineral deficiencies mainly in BPD and RYGB; Macronutrient deficiency with BPD.

Vitamins ADEK, B1 (Thiamine), B12

Iron, Folic Acid, biotin, selenium, zinc, copper, calcium

Only 30-35% patients are vitamin compliant

Prevention Adherence to high protein diet

Lif l l t ti f RYGB SG BPD Lifelong supplementation for RYGB, SG or BPD MVI with iron (Centrum or Equate Complete) Vitamin B12, 1000 mcg IM q mo or 1000 mcg po qdaily Calcium 1200-1500 mg qdaily Vitamin D 800 IU daily Iron 40-65 mg elemental daily Menstruating women may require parenteral iron infusions

Halverson, J.D., (1992).Metabolic risk of obesity surgery and long-term follow-up. American Journal of Clinical Nutrition, 55, S602-605.

Post-Op Monitoring

Follow-up Lab Tests

At 3 and 6 months postoperatively and then yearly

CBC, Electrolytes, Glucose, Creatinine

Iron Studies, Ferritin

Aminotransferases, AlkPhos, Bilirubin, Albumin

Lipid profile

CThiamine, Folate, Zinc, Copper

25 OH vitamin D, PTH

Virji, A., Murr, M. (2006). Caring for patients after bariatric surgery. American Family Physician, 73 (8), 1403-1408.

Bradley 21

Long-Term ComplicationsCompliance Issues

Persistent vomiting due to pouch distention More common with purely restrictive procedures p y p

VBG and ABG Most due to non-adherence to dietary

recommendations Small portions Chewing thoroughly Eating slowly Waiting one hour after eating before drinking Waiting one hour after eating before drinking

Other causes of vomiting – pain meds, vitamins, dehydration, gastroenteritis, stricture, stomal stenosis

Bohn, M., Way, M., Jemieson, A. (1993). The effects of practical dietary counseling on food variety and regurgitation frequency after gastroplasty for obesity. Obesity Surgery, 3, 23-28.

The End