Bariatric surgery Flashcards
Health Implications of Obesity
Hypertension or high blood pressure coronary heart disease, dyslipidaemia type two diabetes stroke gallbladder disease liver disease such as non-alcoholic fatty liver disease osteoarthritis obstructive sleep apnoea and other breathing problems some cancers such as breast, colon and endometrial cancer mental health problems
What is the trend in obesity across ages?
Increases with age between 20-65 years old, followed by a decline
Not due to weight loss but due to high mortality obese people
What is the trend in death from obesity across years?
Risk of death increased from 1985 to 2000
Obesity classes according to BMI
Obese class 1: 30.0 – 34.9 Obese class II: 35.0 – 39.9 Obese class III: (Morbid Obesity): ≥ 40.0
What is the purpose of bariatric surgery
promote significant weight loss and assist/improve weight-related comorbidities
Bariatric surgery associated terms
Weight loss surgery
Obesity surgery
Metabolic surgery
Indications for bariatric surgery
BMI ≥ 40, or
BMI > 35 with significant obesity-related comorbidities
Acceptable operative risk
Failure of non-surgical weight loss
Well-informed, compliant, and motivated patient
Contraindications to bariatric surgery
Active substance abuse (drugs, alcohol) Uncontrolled psychiatric illness Cirrhosis Pulmonary hypertension Severe cardiac and respiratory disease Active pregnancy
eating disorder is not a counter-indication for surgery
Types of surgeries
- Restrictive procedures (restriction of stomach volume)
- Adjustable gastric band (AGB)
- Vertical sleeve gastrectomy (VSG)- most common type - Restrictive + Malabsorptive procedures (restriction of stomach volume + manipulating the intestines)
- Roux-en-Y gastric bypass (RYGB)
- Biliopancreatic diversion with duodenal switch (BPD/DS)
Characteristics of AGB
Adjustable gastric band (AGB)
- Reversible
- Rapid,satiety
- Requires frequent adjustments
- Unknown durability of the band
sodium can be injected into the port to inflate the band and cause more restriction
leaking-> more sodium has to be injected
too tight-> will result in vomiting
Characteristics of sleeve gastrectomy
Most of the fundus is remove (70-80% )
Pyloric sphincter and intestines remain intact
Rapid satiety
irreversible
done through laparoscopy-> less infection and pain, better and faster recovery
describe Roux-en-Y Gastric Bypass (RYGB)
pyloric sphincter is no longer used-> this can lead to rapid gastric emptying
- New gastric pouch is created, excludes the fundus
- bypass of the duodenum and proximal jejunum
- Malabsorption: pancreatic and gastric enzymes reach the proximal jejunum at the anastomoses
- rapid satiety
https: //www.youtube.com/watch?v=vvN4z0lb3A8&ab_channel=NorthwellHealth
Describe Biliopancreatic diversion with duodenal switch (BPD-DS)
Not for everyone, but in case it is done- very effective
pyloric sphincter is used
biggest weight loss
- Sleeve gastrectomy and stomach resection ,
- Common limb ~100m of the ileum
- more malabsorption than RYGB-> pancreatic and gastric and enzymes reach the ileum at the anastomosis
- one or two stage procedure
how to calcualte excess weigth loss?
100× (preoperative weight−initial weight)/ (preoperative weight - ideal weight)
name bariatric surgeries from biggest excess weight loss to smallest
Switch
RYGB and Sleeve gastrectomy
AGB
name bariatric surgeries from biggest % of DM2 resolution to smallest
Switch
RYGB
Sleeve gastrectomy
AGB
rate of weigth loss post-op
- Rapid weight loss occurs over first 12 months post-op
- Most significant loss seen in the first 6 months post-op.
realistic goals post-op
- As per %E WL, individuals may still be categorized as ‘obese’.
- Few patients arrive to their ideal body weight (IBW) as per BMI.
- Goal is for weight reduction to improve overall health outcomes.
Mechanisms of weight loss of surgeries
- Gastric restriction (all surgeries)
- Common limb length (RYGB, BPD-DS): Shorter common limb = more malabsorption
- Gut hormones get altered by surgery (RYGB, sleeve, BPD-DS) - effect subdues after some time, but still will be less than before surgery
↓ Ghrelin (orexigenic hormone) secretion: Produced by the parietal cells (in gastric fundus), which is removed. !
↑ Leptin (produced by adipocytes)
what is a common limb?
common limb is where gastric content and pancreatic juices join
True or False?
! Bariatric surgery resolves type 1 and type 2 diabetes?
FALSE
Can only (possibly) resolve DM2 if <10 years since diagnosis- if 10+ years there is already pancreatic fatigue and organ damage
But weight loss surgery will still improve insulin response
early and late complications of surgery
Early (< 30 days post-op):
- Bleeding, anastomotic leak (risk of tissue not fusing together-> stomach contents leak into abdomen), infection, strictures (strictures most commonly occur with bypass), obstructions
Late (> 30 days post-op):
- Ulcer, stricture, obstruction, hernia, nutrition deficiencies, dumping syndrome, weight regain or weight loss failure, psychological complications, malnutrition
Nutrition Guidelines: PRE-OP
Very low calorie diet (VLCD) 2 weeks prior to surgery
- 800-900 calories
- Low carb (<100g/d), high protein, moderate fat
- Induces ketosis- the point is to get smaller liver size to have a better visibility and lower surgical risk
smaller size is achieved through ketosis
Reduces liver volume by decreasing intrahepatic fat
- Improves visibility for surgeons
- Reduced surgical risks
Nutrition Guidelines: POST-OP
Texture progression:
- To reduce vomiting and allow healing of anastomosis
1. Clear fluids (1-3 days)
2. Full fluids/puree (5 weeks)
3. Solids (for life)
Portion progression:
- 1⁄2 cup to start, ↑ to 1 cup portions per meal/snack
- To reduce vomiting and habituate patient to their new gastric pouch.
Causes of Vitamin & Mineral deficiencies in bariatric surgery
- Reduced dietary intake
- Removal of fundus (less parietal cells): Reduced gastric acidity (hydrochloric acid - HCl-> less protein denaturing, lower iron absorption ) and Reduced intrinsic factor (IF)-> lower b12 absorption)
- Bypassed intestines
- Tolerance issues-> thus avoiding certain foods and missing nutrients from them
RYGB associated deficiencies
Duodenum: calcium and iron
Jejunum: Vit D, folate
Ileum is untouched in procedure but due to less fundus- > less intrinsic factor-> less B12
BPD/DS associated deficiencies
Deficiencies of fat soluble vitamins (ADEK) at greater risk with BPD/DS.
Duodenum: calcium and iron
Jejunum: Vit D E A K, folate
Ileum is untouched in procedure but due to less fundus- > less intrinsic factor-> less B12
Are there protein concerns with bariatric surgery?
Primary protein malnutrition (PM) or protein-energy malnutrition (PEM)
- Rare but at risk in all bariatric surgeries
- Due to decreased oral intake/volume restriction
Secondary PM or PEM
- RYGB (rare) and BPD-DS (uncommon, but possible)
- Due to malabsorption have higher protein needs
LBM loss
- Most LBM loss occurs within 3 months post-op.
- LBM loss may lead to reduced RMR and reduced muscle strength and physical function.
Importance:
- Inevitable lean body mass (LBM) loss, but try to minimize as much as possible.
protein recommendations
Band, sleeve, RYGB: 1.0-1.5 g/kg IBW (~60-120g/d)
BPD/DS: 1.5 – 2.0 g/kg IBW (~90-120 g/d)
Focus on high biological value/high quality protein.
- High PDCAAS: egg white, whey, casein, soy
- Low PDCAAS: collagen, gelatin
Dietary modifications
- Limit liquid calories…but hydrate! Low kcal, low caffeine, low sugar, no carbonation
Order of meal consumption: 1. protein 2. vegetables 3. grains - Reduce frequency of eating out
- Decrease processed foods/simple sugars
- Decrease high fat foods
Behavior modification
! No skipped meals ! Prolong meals ! Chew well ! Portion control (use smaller plates) ! Attention to satiety signals ! Practice mindful eating ! Avoid drinking with meals/snacks: 15 min AC; 30 min PC Because if liquid will mix with solid it will pass the stomach much faster-> rapid gastric emptying-> will get hungry faster
A 27 y.o. female reports:
“I had a gastric bypass 6 weeks ago. I vomit almost everything that I eat.”
“I vomit everything I eat, even puree textures, but I can drink water.”
ule out: esophageal dysphagia (difficulty swallowing) vs stricture (narrowing at anastomosis) vs ?
Investigate causes: ! Poor chewing ! Overeating ! Eating too quickly ! Eating tough/fibrous foods, doughy breads, dry meat ! Stricture
Since she can drink-> possible stricture-> Needs to see doctor or nurse to rule out a stenosis. May need further investigation via a gastroscopy and possible balloon dilatation.
Nutrition Intervention:
! Can suggest meal replacements to optimize nutrition as much as possible.
A 42 y.o. man reports symptoms of shakiness, sweats, nausea, and feeling very unwell. This occurs about 3-4 times/week. He had a gastric bypass about one year ago.
Snacks on ++ chocolate covered raisins at PM snack.
Symptom onset between PM snack and dinner.
No glucometer.
Usually constipated but has diarrhea after PM snack.
Rule out: hypoglycemia and its source Investigate: - Onset of symptoms as related to last meal/snack - Type of food consumed - Diarrhea?
Likely dumping syndrome. Nutrition Intervention: - Healthy snacking - Avoidance of trigger foods (limiting simple sugars) - Label reading (≤25 g absorbable carb)
Describe dumping syndrome
Occurs with RYGB, due to the removal of the pyloric sphincter.
2 phases:
1. “Early” phase:
- Occurs 10-30 min PC
- Due to rapid transit of hyperosmotic food into the jejunum (usually simple sugars)
Symptoms: dizziness, nausea, weakness, rapid pulse, diarrhea
- “Late” phase
Occurs 1 – 3 hours PC
Reactive hypoglycemia due to an exaggerated release of insulin.
A 42 y.o. man reports symptoms of shakiness, sweats, nausea, and feeling very unwell. This occurs about 3-4 times/week. He had a gastric bypass about three years ago.
Symptom onset between PM snack and dinner.
High carb, low protein lunch and PM snack.
Possibly nesidioblastosis (hyperinsulinemic hypoglycemia).
Nutrition Intervention:
- Increase protein:carb ratio at lunch and PM snack.
- If no change in symptoms, to see an endocrinologist.
A patient had bariatric surgery (any procedure) 4 months ago and complains of hair loss.
Is hair loss always a sign of poor protein intake?
- No. Consider ‘shock loss’ (telogen effluvium), the thinning or shedding of hair due to physiological stress of surgery.
- Occurs between 3 - 6 months post-op (early hair loss).
- Reassure patient and encourage adequate protein intake and vitamin compliance.
symptoms of zinc deficiency:
Hair loss
Dysgeusia
Consider zinc deficiency if + intervention
- Hair loss begins > 6-9 months post-op
- Attaining est protein needs, and
- Insufficient zinc supplementation
Nutrition Intervention:
- Zinc supplementation: 60 mg elemental BID
- Monitor plasma zinc in bloodwork
- Suggest complete multivitamin to patient considering:
- Palatability, ease of swallowing pills, and cost to patient.
A patient returns to see you 14 months after her bariatric surgery. She has regained 25 lbs. She reports she is constantly hungry and she can tolerate a lot more food that she used to, and she is very discouraged.
How can you explain this?
You review her dietary habits and identify that she has been drinking fluids with her meals.
Nutrition Intervention:
Educate pt on the reason for delaying fluids and its
consequences. Suggest tips to make this easier for the pt.
A patient regained 60 lbs. You have previously reviewed all the dietary habits that needed modification and, via motivational interviewing, the patient has set some small goals for lifestyle change.
1 month later: +6 lbs despite having made some dietary changes.
2 months later: + 7 lbs; she reports ++ grazing when she is stressed, bored,
and angry.
What do you do?
Suggest the benefits of seeing a psychologist for better management of her emotions. Dietary counselling has not provided a solution to her emotional eating thus far. Refer her and offer continued dietary support to encourage positive changes. Keep in contact with psychologist.
A patient is admitted to the hospital ward that you cover. She has been diagnosed with an anastomotic leak.
- Most feared surgical complication (fatal)
- Occurs at suture lines
- Gastric contents leak into abdomen
What would your nutrition care plan be?
- TPN – total parenteral nutrition
- Why not enteral feeds? Bowel needs to be at rest to encourage the healing process.
