Bariatric Surgery

Question 1

pros of surgical treatment for obesity

Answer 1

*50-75% weight loss
*less than or equal to 15% failure rate
*medical CO-MORBIDITIES IMPROVE/resolve

Question 2

cons of surgical treatment for obesity

Answer 2

*expensive
*early/late surgical risks
*long-term nutritional deficiencies common

Question 3

indications for bariatric surgery - categories

Answer 3

1. obesity class
2. age
3. history of FAILED DIETARY + DRUG TREATMENT
4. contraindications

Question 4

indications for bariatric surgery - OBESITY CLASS

Answer 4

*BMI > 40
OR
*BMI > 35 + uncontrollable metabolic complications

Question 5

indications for bariatric surgery - AGE

Answer 5

*most programs consider patients age 18-65+
*surgery in children < 18 yo is increasing

Question 6

CONTRAINDICATIONS for bariatric surgery

Answer 6

*advanced renal, hepatic, cardiopulmonary disease
*untreated cancer
*dementia
*substance abuse
*depression
*noncompliance

Question 7

bariatric surgical options

Answer 7

1. restrictive: laparoscopic sleeve gastrectomy (LSG)
2. combination restrictive + malabsorptive: laparoscopic Roux-en-Y gastric bypass

Question 8

sleeve gastrectomy

Answer 8

*stomach is resected to 15% of its original size
*MOA: reduced meal side; fat malabsorption
*advantages: easy to perform; up to 60% EWL at 4 years
*disadvantages: non-reversible; not as effect as RYGB for very high BMI patients

Question 9

risks with sleeve gastrectomy

Answer 9

*death -> 1 in 500
*leaks
*bleeding
*gastric stenosis
*GERD
*dilation and weight gain

Question 10

laparoscopic Roux-en-Y gastric bypass (RYGB)

Answer 10

*stomach is bypassed and a roux-en-Y limb is created
*MOA: increased secretion of anorexic gut hormones GLP-1 and PYY
*advantages: up to 75% EWL at 4 years; immediately improves insulin resistance & glucoregulation; best improvement in other metabolic co-morbidities
*disadvantages: GREATEST INCIDENCE OF LONG-TERM NUTRITIONAL COMPLICATIONS

Question 11

surgery-related risks of Roux-en-Y gastric bypass (RYGB)

Answer 11

*early:
-death -> 1 in 300
-leaks
-pulmonary embolism
-deep vein thrombosis

*late:
-ulcers, strictures
-bowel obstruction
-dumping syndrome
-cholecystitis

Question 12

nutritional complications of Roux-en-Y gastric bypass (RYGB)

Answer 12

1. protein deficiency
2. mineral deficiencies (iron + calcium malabsorption)
3. vitamin deficiencies (B1, B3, B9, B12, A, and D)
4. bacterial overgrowth
5. enteric hyperoxaluria

Question 13

protein deficiency in Roux-en-Y gastric bypass (RYGB)

Answer 13

*malabsorption: impaired intra-luminal digestion + decreased small bowel surface area
*protein-loosing enteropathy: SIBO -> mucosal inflammation -> disrupted blood-gut barrier (leaky gut)
*symptoms:
-hypoalbuminemia
-peripheral edema
-low transferrin, prealbumin, IgG/A
-worsening diarrhea, gas, bloating
-UNEXPLAINED RAPID WEIGHT GAIN

Question 14

treatment of protein deficiency post-Roux-en-Y gastric bypass (RYGB)

Answer 14

1. rule out SIBO
2. evaluate for protein-losing enteropathy
3. INCREASE INTAKE OF HIGH PROTEIN FOODS

Question 15

mineral deficiencies in Roux-en-Y gastric bypass (RYGB)

Answer 15

1. iron malabsorption
   -bypassed gastric Fe3+ reduction
   -bypassed duodenal Fe2+ absorption
2. calcium malabsorption
   -secondary to fat malabsorption

Question 16

symptoms of iron malabsorption post-Roux-en-Y gastric bypass (RYGB)

Answer 16

*pica (usually manifests as ice chewing)
*iron-deficiency microcytic anemia

Question 17

symptoms of calcium malabsorption post-Roux-en-Y gastric bypass (RYGB)

Answer 17

*accelerated osteoporosis
*enteric hyperoxaluria
*oxalate kidney stones

Question 18

treatment of iron deficiency post-Roux-en-Y gastric bypass (RYGB)

Answer 18

*increased intake of red meats (heme iron is better absorbed)
*oral (inorganic) iron supplements
*oral heme iron supplements
*IV iron infusions

Question 19

treatment of calcium deficiency post-Roux-en-Y gastric bypass (RYGB)

Answer 19

*increased intake of calcium-rich foods
*oral calcium supplementations:
-Ca oxide (can cause diarrhea)
-Ca citrate & glycinate are more efficiently absorbed

Question 20

vitamin deficiencies in Roux-en-Y gastric bypass (RYGB)

Answer 20

1. B vitamins (thiamine, niacin, folate) - loss of absorptive surface area
2. vitamin B12 (reduced gastric intrinsic factor availability + ineffective IF binding)
3. fat soluble vitamins (A and D) secondary to fat malabsorption

Question 21

symptoms of B-vitamin deficiencies post-Roux-en-Y gastric bypass (RYGB)

Answer 21

*glossitis & cheilosis
*macrocytic anemia
*neurologic dysfunction

Question 22

symptoms of vitamin A/D deficiencies post-Roux-en-Y gastric bypass (RYGB)

Answer 22

*night blindness
*accelerated osteoporosis

Question 23

treatment of vitamin deficiencies post-Roux-en-Y gastric bypass (RYGB)

Answer 23

*AVOID large, solid multivitamin pills; instead:
-GUMMY VITAMINS
OR
-supplement vitamins INDIVIDUALLY

Question 24

post-bariatric surgery diet

Answer 24

*new eating pattern (“behavioral pylorus”):
-multiple small meals
-careful mastication
-slow: 20-30 minutes to eat a meal
-solid and liquid foods at separate times
*new dietary composition (increased protein and decreased fat)
*supplements (vitamins + minerals)