ch 12 Flashcards
Obesity
Defined by WHO as BMI > 30 kg/m2
• 2015 Canadian Health Measures Survey
– 28% of population are obese
• USA, prevalence has doubled between 1980-2004
– Disproportionate increase in those with BMI > 40 kg/m2
• Risk and causative factor for ++comorbidities
– DM, heart disease, HTN, cancer, asthma, thromboembolic disease, stroke
etc.
Obesity Treatments
Lifestyle – Diet, exercise, counselling • Pharmacotherapies – 2 approved medications in Canada • Orlistat (Xenical®) • Liraglutide 3 mg (Saxenda®) • Bariatric surgery – Most effective means for long-term/sustained weight loss and reductions in obesity-related comorbidities and complications
Bariatric Surgery Procedures
• Restrictive
– Reduces the amount of food the stomach can hold
• Laparoscopic gastric banding
• Gastric sleeve
• Malabsorptive
– Results in malabsorption of nutrients
• Combination (restrictive and malabsorptive)
– Roux-en-Y gastric bypass (RYGB)
– Biliopancreatic diversion with duodenal switch
Gastric Banding 472 Nutrition in Clinical Practice 32(4)
• Reduces gastric reservoir capacity • Brands: Slimband, Lap-Band System, Realize Brand • Silicone band filled with saline – ↑ saline à tightens band • Makes stomach smaller – ↓ saline à loosens band • $11,000-20,000 • Weight loss slower and gradual vs resections
472 Gastric Sleeve Nutrition in Clinical Practice 32(4)
Greater curvature of stomach is removed and tubular stomach created • Reduces stomach size – Restricts amount of food one can consume – Feel “full” sooner
Roux-en-Y Gastric Bypass (RYGB) - 1
Creation of small gastric pouch – Size of an egg • Jejunum divided into 2 “limbs” – Roux limb (jejunum) • Food flows directly from pouch to Roux limb, bypassing stomach – Biliopancreatic limb (duodenum) • Stomach continues to produce digestive juices that flow into this limb which is reattached below the roux limb (forming a “Y”) • Small pouch limits food intake • Bypassing small intestine: – loss of absorptive surface area
– Reduced nutrient absorption
Biliopancreatic Diversion with Duodenal Switch
• Sleeve gastrectomy with pylorus • Creation of a small roux limb with short common channel – i.e 100-150 cm • Length of channel determines degree of malabsorption
Sleeve Gastrectomy
Roux-en-Y
BPD-DS
Sleeve Gastrectomy • Versus Roux-en-Y – Less invasive – Technically easier – Faster to perform – Safer • Limited studies on longterm outcomes • Early studies show potential benefit but less so vs RYGB
Roux-en-Y • Traditionally considered the gold standard • Preferred procedure (Canada) • Best outcomes with respect to successful long-term weight loss • Reports of weight loss: – 45-85% of excess weight – 20-30% initial weight
BPD-DS • Associated with significant malabsorption • Reserved for patients with BMI >50 kg/m2
• Excess weight (EW) loss
– Excess weight: total weight above reference ”ideal” of BMI 24.9 kg/m2 – Typically expressed as a percent • Expected outcomes – 20-30% loss actual weight – 50-60% loss EW
Clinical Outcomes Associated w/ Bariatric Surgery - 1
• Reduction in all-cause mortality
– Related to improvements/decreased incidence of DM, cancer, CVD
• Improvements/resolution in obesity-related co-morbidities
– T2DM à resolution or significant improvements in glycemic control
– Cardiovascular disease à reduction in time to first cardiac event
– Dyslipidemia à improvements in blood lipid profile
– HTN à resolution or improvement
– Obstructive sleep apnea à resolution
– GERD à Roux-en-Y resolved; gastric sleeve, may worsen
• Improved mobility
Mental health à evidence is mixed
– High prevalence of depression in individuals undergoing surgery
– Modest reductions in clinical depression but not maintained
– 50% increased risk of self-harm emergencies post-surgery
• Pre-op: 2.33 events per 1000 patients; post-op: 3.63 events per 1000 patients
– Post RYGB:
• ↑ risk of diagnosis of depression
• ↑ rate of suicide attempts (compared with non-obese population)
• ↑ risk of diagnosis of alcohol/substance abuse disorders
Criteria to be a Surgical Candidate
BMI > 40 kg/m2 • BMI 35-40 kg/m2 considered if also have 2+ medical conditions – DM – Sleep apnea – Cardiopulmonary problems – HTN • Previous weight loss attempts
• Be between the ages of 18 and 59
• Must be a non-smoker at the time of referral
• No active substance abuse
• Cannot be pregnant, lactating, or become pregnant
• Be motivated and be willing to make eating and lifestyle
changes
• Commit to all aspects of the program
• Be psychologically and medically fit for surgery
A
Multidisciplinary Team
Physicians – Bariatric surgeons – Obesity specialist (i.e. American Board of Obesity Medicine Certified • Mental health professionals – Psychiatrists – Psychologists – Social workers • Dietitians • Exercise physiologists, kinesiologists
Pre-Op Nutritional Management
• Consultation with a dietitian
– Food, activity & mood intake journals
• Learn how to monitor intake
• Understand how food may be connected to mood
– Education
• Demonstrate ability to adhere to post op diet & supplementation regimen
Peri-Op Nutritional Management
Peri-operative (2-3 weeks prior to surgery)
Optifast® program
– Low calorie, low fat, high protein diet
– 4 packets per day
• Provides daily: 900 kcal, 90 g protein, 30 g fat, 67 g CHO
– Cost: $90/week (patient pays)
• Purpose
– Reduce size of liver
– Reduce visceral fat tissue around liver
Nutritional Management: POD 1-2
Day 1: Clear Fluids – 15 mL q15min • Day 2: Clear Fluids – 30 mL q15min Nutritional Management: POD 1-2 Fluids Allowed • Water • Diluted fruit juice (50/50) • Broth • Tea • No sugar added Jell-O®
