Flashcards in Obesity and Bariatric Surgery Interventions Deck (64):
What BMI classifies someone as class I obesity?
What BMI classifies someone as class II obesity?
What BMI classifies someone as class III obesity?
What are factors contributing to obesity?
Lack of sleep
What are medical complications of obesity?
Non-alcoholic fatty liver disease
Gall bladder disease
What are reasons for bariatric surgery?
Chronic disease and obesity-related condition prevention
Improvement in quality of life
What will bariatric surgery NOT do for a patient?
Unlikely to achieve "normal" BMI or "thin" appearance
Surgery will not change environment, behaviours, relationships. With the lifestyle changes, almost any procedure will work. Without the lifestyle changes, no surgery will work long term
What are indications for bariatric surgery?
BMI of over 40
BMI of over 35 with obesity-related co-morbidity
Failure of diet and exercise
What are some of the current procedure methods? How do hormones affect these procedures?
Restrictive (consume less food)
Malabsorptive (decreased absorption of calories eaten)
Combined restrictive and malabsorptive
Significant hormonal factors contribute to weight loss and disease remission in gastric bypass and sleeve gastrectomy
What are some of the current procedures?
Roux-en-Y gastric bypass (RYGB)
Sleeve gastrectomy (SG or VSG)
Bilio-pancreatic diversion with duodenal switch (not preformed in MB)
Adjustable gastric band (e.g., lap-band, slim band)
Describe the roux-en-Y gastric bypass
Combined restrictive and malabsorptive procedure
Strong hormonal component to weight loss and comorbidity resolution
Describe the sleeve gastrectomy
Restrictive procedure with hormonal component
Describe the bilbo-pancreatic diversion with duodenal switch
Mainly malabsorptive, some restriction and hormonal change
Describe the adjustable gastric band
Purely restrictive procedure; there's a ring around the stomach that inflates. As it inflates, it makes a small pouch and it makes the patient feel full
Fewer complications but higher failure rate
Lowest weight loss and disease resolution (10-15% total weight loss)
How does the roux-en-Y gastric bypass work?
The stomach is divided into two parts.
Small stomach pouch (15-30 ml) causes restriction
Food enters the small stomach and goes down into the jejunum. Food bypasses the distal stomach, duodenum and a portion of the jejunum (results in malabsorption)
The duodenum and the rest of the stomach is reattached later
Significant hormonal changes also occur: increased insulin sensitivity and production, increased satiety, decreased hunger
What are the results of the RYGB?
Results in 30% total weight loss (average)
Best resolution of comorbidities (mainly type II diabetes mellitus)
How does the sleeve gastrectomy work?
The large curvature of the stomach (80% of the stomach) is removed, leaving a narrow tube
The pyloric sphincter is still there, which helps with satiety because the food doesn't leave the stomach quickly (decreased hunger)
Limited macronutrient malabsorption
What are the results of the sleeve gastrectomy?
Results in 20% total weight loss
Comorbidity resolution between band and gastric bypass
Describe the pre-op diet
Goal is the shrink the liver to make surgery safer and easier
Some weight loss occurs, normal is 7-15 lbs
Boost diabetic: 5 bottles/day (950 kcal, 80g of protein, 80g carbohydrate per day)
What type of diet should a patient be consuming post-op?
High protein, high fibre, low-moderate carbohydrate diet life-long
How much protein should a patient be consuming post-op?
Minimum 60g/day for at least the first year
Some require protein supplements to meet needs
How many calories should a patient be consuming post-op?
Around 1200 kcal/day long-term
500-600 kcal/day for the first two weeks post-op, increasing as meal volume/tolerance increases
How often should patients be eating post-op?
Frequent meals: minimum 3 meals plus 1-3 snacks
Limited to 1-1.5 cups of food per meal
How much fluid do patients need to consume post-op?
Minimum 2L/day, separate from meals
Limit caffeine and caloric beverages
Avoid carbonated drinks
Try to separate fluids and solids
What should the patient consume on operative day and post-op day 1 (in hospital)?
Clear fluids and protein supplement
What is phase 1 of post-op diet progression?
Days 1-7 post-op
Clear fluids and meal replacements/protein shakes
What is phase 2 of post-op diet progression?
1-4 weeks post-op
Focus on protein-rich foods
What is phase 3 of post-op diet progression?
Soft, minced foods
4-8 weeks post-op
Portions: 0.5 cup of food per meal, 6-7 small meals per day
Begin to separate beverages from meals
What is phase 4 of post-op diet progression?
Starts 8-12 weeks post-op
Portion: 0.75-1 cup per mea
What are the required vitamins and minerals post-op?
Increased doses and/or other micronutrient supplements may be required
How much of a multivitamin/mineral should a patient have?
1 per day
At least 15 mg, 2 mg copper, zinc, selenium
100% RDA for at least 2/3 nutrients
How much vitamin B12 should a patient have?
How much iron should a patient have?
25-40 mg, ferrous gluconate
At least 2 hours from calcium/thyroid medication
How much calcium should a patient have?
1200-1500 mg/day, in 3 doses
Must be taken with food
At least 2 hours from iron/thyroid medication
How much vitamin D should a patient have?
Taken with calcium for best absorption
When should patients start taking required vitamins and minerals?
Patients should take all supplements by 2 weeks post-op
Large tablets must be cut, crushed or chewed for the first while (tablets/capsules smaller than an M&M are generally fine to swallow whole)
Do vitamins and minerals have to be solid?
Liquid supplements may be better absorbed and/or tolerated
Alternative routes/types of supplementation are also available (injections, dissolvable strips, chewables)
What are some potential early complications of surgery?
Staple line leak
Nausea and vomiting
What ares some potential late complications of surgery?
Adhesions/small bowel obstruction
Gastric and/or anastomotic ulcers
Nausea, vomiting, diarrhea or constipation
Pouch dilation (stretching)
What are some early nutrition complications?
Describe food intolerances
Fresh breads, pasta, rick, corn, fruit and vegetables skins, tough meats, lactose
Intolerances are individual; some resolve over time
Increasing intolerances could signal complications (ulcer, stricture, etc.)
Multiple intolerances may decrease diet quality, macro- and micronutrient intake
Describe dumping syndrome
Caused by the rapid transit of simple/free sugars or greasy foods into lower small intestine
0-60 minutes after eating
Nausea, vomiting, diarrhea, stomach pain, dizziness, hypoglycemic symptoms
Treatment: avoid suspect foods and beverages, read food labels/ingredients lists carefully
What are some late nutrition complications/
Kidney stones (oxalate)
Lack of appetite
Describe hair loss
Common 3-6 months post-op
Over 9 months post-op is likely due to nutrient deficiency
What causes kidney stones?
Increased oxalate retention, decreased fat intake, decreased calcium intake, inadequate hydration, other metabolic factors
How are kidney stones treated?
Minimum 2 L of fluid/day, at least 100 mg calcium, low oxalate diet
Describe reactive hypoglycemia
Causes: inadequate CHO, missed meals, excessive exercise or medication, increased incretin release
1-3 hours after meals (hypoglycaemic symptoms)
Focus on complex/high fibre CHO, combining CHO and protein for snacks
Describe a lack of appetite
Hunger cutes change or may be absent due to decreased appetite-stimulating gut hormones (e.g, ghrelin, etc.)
Use reminders to eat, regular meal pattern, measure portions
Occasionally appetite-stimulating medications may be added
What are common micronutrient deficiencies?
Vitamin A (rare)
Describe iron deficiency
Up to 51% of patients become deficient
Symptoms: fatigue, headaches, insomnia, hair loss
Treatment: up to 300 mg oral elemental iron + 250 mg vitamin C (at least 2 hours between iron/calcium/thyroid medication)
May need iron infusions in refractory cases
Describe zinc deficiency
Up to 28=36% 1 year post-op; potentially refractory requiring ongoing supplementation (requires concurrent copper supplementation
Describe copper deficiency
Increasing prevalence, appears over 2 years post-op
Symptoms: ataxic gait, extremity numbness, unexplained anemia
1 mg Cu: 8-15 mg Zn in supplements to prevent deficiency
Describe vitamin A deficiency
Rare, up to 10-17% of patients
More common with poor diet and inadequate supplementation
Occular changes lead to finding
Some patients require ongoing high-dose supplements
Describe thiamine deficiency
More common with persistent vomiting and reduced food intake
Describe vitamin B12 deficiency
Low acid environment, decreased digestion of vitamin from foods
Exclusion of distal stomach, therefore reduced intrinsic factor produced
May require alternative routes
Describe vitamin D deficiency
Decreased absorption from foods, decreased intake of vitamin D rich foods
May require short-term high doses to reach normal levels
What medications needs to be changed?
Anti-depressants, anti-anxiety medications, etc.
Avoid extended release or enteric coated medications
How are NSAIDs changed?
They post an increased risk of ulcer
Must be avoided roused only in small doses for 2-3 days
How are oral contraceptives changed?
Absorption rates vary after surgery, but are generally decreased. We are unable to predict absorption or effectiveness
Patients should choose non-oral hormonal contraceptives or barrier methods
How are anti-depressants, anti-anxiety medications, etc. changed?
Absorption changes are common and variable post-op
Unable to predict how a patient will respond to meds post-op
Close monitoring by patient and care team of symptoms to readjust medication in the early post-op period
Why should patients avoid extended-release or enteric located medications?
Decreased absorption area
Increased transit through gut
Decreased bioavailability for patients
Can patients consume alcohol?
There is an increased alcohol sensitivity; due to weight loss, faster gastric emptying and ethanol absorption and slower metabolic clearance
Increased ulcer risk with increase intake
Patients should abstain from alcohol for 12 months post-op (may reintroduce alcohol in small amounts if no complications)
Can patients become pregnant?
Patients should wait at least 12-18 months after surgery to get pregnant
Increased risk to fetus during period of rapid weight loss, greatest risk of nutritional deficiencies