Update on Bariatric Surgery. Learning Objectives: At the end of this lecture you should be able to: Currently Available Options

Transcription

1 Update on Bariatric Surgery Dan Bessesen, MD Chief of Endocrinology; Denver Health Medical Center Professor of Medicine, University of Colorado School of Medicine Learning Objectives: At the end of this lecture you should be able to: Describe the 3 most commonly used bariatric surgical procedures. List the effects of the 3 available procedures on weight, diabetes and overall mortality List several common complications of bariatric surgery and how to prevent and evaluate them. Currently Available Options Accept weight where it is Diet/Exercise: 3-10% weight loss Drugs: 5-12% weight loss Medically Supervised/Combination of Diet + Drug: 10-15% weight loss Surgery: 15-30% weight loss Effectiveness Low High 1

2 Currently Available Options Accept weight where it is Diet/Exercise: 3-10% weight loss Drugs: 5-12% weight loss Risks/Time/Money Medically Supervised/Combination of Diet + Drug: 10-15% weight loss Surgery: 15-30% weight loss Low High Treatment A Guide to Selecting Treatment BMI category Diet, physical activity, and behavior therapy With co-morbidity Pharmacotherapy With co-morbidity Surgery With co-morbidity + The Practical Guide Most Common Bariatric Surgery Procedures Roux-en-Y Gastric Bypass (57%) Malabsorptive & Restrictive Bypass a portion of the small intestine and create a 15-30cc stomach pouch Adjustable Gastric Banding (37%) Restrictive Place implantable device around upper most part of stomach Sleeve Gastrectomy (6%) Restrictive Resect approximately three-fourths of the stomach 260,000 procedures annually, 90% laparoscopic 2

3 Stampede Trial: Randomized Trial of Bariatric Surgery for T2DM N Engl J Med 2012;366: Previous studies suggested DM went into remission following bariatric surgery. 150 patients randomized to intensive medical therapy, gastric bypass or sleeve gastrectomy for management of type 2 diabetes Average baseline A1C was 9.2% 93% follow up at 12 months Health Benefits: Stampede Trial: N Engl J Med 2012;366: CV Medications Stampede Trial: N Engl J Med 2012;366:

4 Adverse Events Stampede Trial: N Engl J Med 2012;366: Swedish Obese Subjects Trial Bariatric Surgery vs Usual Care Nonrandomized prospective controlled study 2010 pts had surgery compared to 2037 contemporaneously matched controls Began 1987 Median follow up 14.7 years 2012 papers published on diabetes, cardiovascular, cancer and health care utilization endpoints Weight loss in the SOS JAMA. 2012;307(1):

5 Diabetes Incidence in the SOS N Engl J Med 2012; 367: Correlates of DM Development in the SOS 5

6 Benefits Weight loss roughly 30% (50-60% of excess weight) with GBPS Maintained for >15 yrs Lap band: 20-25% less risk Sleep apnea: Improved in almost all Hypertension: improved in half Gastroesophageal reflux: improved in most Urinary incontinence: improved in most Likely reduced mortality Annals of Surgery 237: ,2003 Sugarman Bariatric Surgery is Associated with a Reduced Mortality: the SOS Study Adjusted Risk Patio=0.71 P=0.01 MI: 25 in control Group 13 in the Surgery group Cancer: 47 in The control group 29 in the surgery group Sjostrom L NEJM 2007: Cardiovascular Events in the SOS JAMA. 2012;307(1):

7 Cancer in the SOS Lancet Oncol 2009; 10: Risks of Bariatric Surgery: the LABS Study Flum DR, N Engl J Med Jul 30;361(5): Gastric Sleeve 7

8 Sleeve Gastrectomy Consensus conference convened by ASMBS 2009 Self report of 106 surgeons on 14,776 sleeve gastrectomy operations Mortality=0.2% Average EWL=60% at 1 year, 62% at 3 years and 49% at >4yrs Staple line leak was the most common complication occurring in 1.5-2% Concluded that this is a reasonable primary operation Surg Obes Relat Dis Jul-Aug;5(4): The ASMBS therefore recognizes SG as an acceptable option as a primary bariatric procedure and as a first stage procedure in high risk patients as part of a planned staged approach. Based on the current published literature, SG has a risk/ benefit profile that lies between the laparoscopic adjustable gastric band and the laparoscopic Roux-en-Y gastric bypass. Micronutrient Deficiencies Primarily an issue with RYGB (Lap band can get thiamine deficiency) Predictable based on the bypassed segments Preventable with appropriate monitoring and supplementation Fe, Ca, B12, Vitamin D, Folate, Thiamine 8

9 Thiamine Without supplementation, can become acutely deficient in the post-operative period especially if lots of vomiting. Sx: Double vision, ataxia, nystagmus, facial weakness, polyneuropathy, confusion, Wernicke s encephalopathy Beriberi Dry: symmetric peripheral polyneuropathy Wet: high output CHF Rx: 100 mg IV or IM daily x 7-14 days, the 10 mg/d orally till recovery Iron Goal is to pick up early with monitoring. Most sensitive test is ferritin. To prevent all (female) pt should be on MVI. Prenatal MVI has increased Fe and Folate. If deficiency develops try oral replacement % may need parenteral replacement (Ferrlecit, INFed, Jenofer etc). B12 Prevention: RDI about 1 mcg/d Oral crystaline B12: mcg/d Sublingual 500 mcg/d Nasal spray (Nascobal): 500 mcg/wk IM: 100 mcg/mo 9

10 Calcium/Vitamin D 25OH D deficiency is very common Obesity Dark skinned people Present pre-operatively in 30-40% Replace pre-operatively if deficient Calcium/Vitamin D Post-operatively Ca citrate mg/d (has 400 u D) Prenatal MVI: u/d D Monitor 25OH D level every 3 months May reduce Ca supplement if person is tolerating and eating a lot of dairy. Consider DEXA at 1-2 years post-op and every 2 years after. Managing Co-Morbidities Diabetes: immediately after surgery Stop sulfonylureas, cut insulin in half SMBG to adjust further, glucose declines rapidly Hypertension: immediately after surgery Stop diuretics, reduce other medications Arthritis Stop NSAIDS 10 days pre-op avoid for 6-12 months OSA: CPAP mask and pressure may need adjustment GERD, Urinary incontinence, hyperlipidemia: monitor 10

11 Medication Adjustments Essential medications should be administered in regular-release rather than sustained release formulations to offset the altered GI absorption after surgery. Tolerance can be improved by crushing the tablets or liquid formulations during the early postoperative days. Pregnancy Fertility increases following weight loss. Avoid getting pregnant for the first year after surgery. BCP may not work because of poor absorption. Pregnancies need to be monitored, but outcomes appear good Lap band: May need adjustment if pregnant Vitamins, micronutrients critical Anastamotic Leak Six Cardinal Symptoms of leaks: Malaise Feverishness Shoulder pain (leak til proven otherwise) Abdominal pain Shortness of breath Increased thirst 11

12 The Dreaded Leak continued. 10 Cardinal Signs of a leak Tachycardia: pulse rate > 120 Respiratory rate > 22 Fever Extravasation of contrast on UGI Pleural effusion Abdominal tenderness / Rebound tenderness Sitting in a Buddha position Pursed lips Tenesmus Other issues Depression Many expect things to get better post-op Pre-existing depression exacerbated by stress of surgery Suicides increased post operatively in some series Ask about mood post-op Too much weight loss too fast. Look for signs of volume depletion Puts at risk for infection Weight Regain After Gastric Bypass Obesity Surg 18: , 2008 Prospective study of 782 GBPS patients form one institution Weight nadir occurred at an average of 18 months 50% of patients experienced some regain Average regain was about 8% Regain and surgical failure were higher in the super-obese 12

13 Who is a Good Candidate? BMI>35 (30 with diabetes?) with comorbidities or >40 without Age Co-morbidities: Diabetes, sleep apnea, reflux > Hypertension, DJD Failed other forms of therapy No serious, active cardiac, pulmonary, or psychiatric disease Summary Bariatric surgery has increasingly been shown to have dramatic health benefits and risk is declining due to improved surgery. There has been a shift from lap bands towards sleeve gastrectomies due to long term complicatoins. Nutritional deficiencies require ongoing supplementation following gastric bypass. Think about mechanical complications/ failures. Bariatric Surgery Resources American Society for Bariatric Surgery International Bariatric Surgery Registry (IBSR) International Federation for the Surgery of Obesity Betsy Lehman Center for Patient Safety and Medical Error Reduction: Expert Panel on Weight Loss Surgery 13

14 Bariatric Surgical Guidelines American Association of Clinical Endocrinologists/the Obesity Society/ American Society for Metabolic and Bariatric Surgery Evidence based A-D recommendations 164 recommendations 777 references 83 pages long 14