Bariatric Surgery Flashcards
BMI classification: obesity
Class i: 30.0-34.9
Class ii: 35.0-39.9
Class iii: >/=40.0 (morbid obesity)
(4) Who are recommended to do BS target patients?
- 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
the Purpose of BS
- The purpose is not to lose weight for appearance looking or ideal body weight
- But more focus on the health outcome and improvement of lifestyle
- assist/improve weight-related comorbidities.
what does mean failure in BS?
Failure = did not reach the goal or weight regain
who tends to have better outcome
M, young, low BMI
(6) Contradictions to BS
- Active substance abuse (drugs, alcohol
- Uncontrolled psychiatric illness: at least be stable for a year and fully understand what’s going as the process.
- Cirrhosis
- Pulmonary hypertension
- Severe cardiac and respiratory disease
- Active pregnancy
four types of BS
AGB
Sleeve gastrectomy
RYGB
BPD-DS
AGB (3)
- Reversible
- Adjustable: may loose, adjust by mm
- Rapid satiety
Sleeve gastrectomy (4)
- Removed most fundus
- Pyloric sphincter and intestines remain intact
- Rapid satiety
- Irreversible
RYGB(4)
Roux-en-Y Gastric Bypass
1. New gastric pouch, excluded the fundus 2. Bypass the duodenum and proximal jejunum 3. Malabsorption: pancreatic gastric enzymes reach proximal jejunum at the anastomosis 4. Rapid satiety
BPD-DS (5)
Biliopancreatic diversion with duodenal switch
- For extreme obese cases
- Sleeve gastrectomy and bowel resection
- Common limb ~ 100cm of the ileum (the only functional gut system)
- More malabsorption than RYGB. Pancreatic and gastric enzymes reach the ileum at the anastomosis.
- Not reversible
%EWL
%Excess weight loss
= (Pre-op BW – CBW x 100)/ (Pre-op BW - IBW )
Outcome of Wt loss
• Insulin resistance can resolve immediately after BS
○ Due to the change of hormone adaption
○ Regardless to weight loss
○ Definitely prolong the 89% patients has reduced the mortality after 5 yrs post- surgery.
90% increases life span
BPD-DS
pattern: rate of post-surgery wt loss
- Rapid weight loss occurs over first 12 months post-op
- Most significant loss seen in the first 6 months post-op
Most LBM loss occurs within 3 months post-op.
BMI and real outcome
Goal is for weight reduction to improve overall health outcomes
- As per BMI, individuals may still be categorized as ‘obese’.
Few patients arrive to their ideal body weight (IBW) as per BMI.
why patients are easy to feel hungry after BS?
the length of common limb become shorter, so less absorption in the gut. However, the the hormone excretion hasn’t reduced
gastrectomy : AGB, Sleeve, RYGB, BPD-DS
AGB: temporary narrow the volume of stomach
Sleeve: permanently narrow the volume of stomach
RYGB: cutted stomach (excluded the fundus) to proximal jejunum
BPD-DS: cutted stomach to ileum
common limb vs alimentary track
common limb= start from the point where pancreatic limb joins to alimentary limb
how does BS helps weight loss? (3) and give the types of surgery
- Gastric restriction (all surgeries)
- Common limb length (RYGB, BPD-DS): Shorter common limb = more malabsorption
- ↓Gut hormones ↓ (↑ after a year) Ghrelin (appetite);↓ Leptin
how does BS help to reduce Ghrelin production
(orexigenic hormone) secretion, which is Produced by the parietal cells (in gastric fundus), which is removed;
how does BS help to reduce Leptin production
produced by adipocytes, which will reduce once weight loss happens after BS
how does BS help to reduce gut hormone production
the shorter length of alimentary limb
BS can resolve diabetes (T/F)
F Can only (possibly) resolve DM2 if < 10 yrs since diagnosis
how does BS improve diabetes (T2)?
improve hormone sensitivity once the absorption decease
3 common complications at early post-op period
Bleeding, anastomotic leak (there is an opening at the cut), infection
3 common complications at late post-op period
nutrition deficiencies, dumping syndrome, weight regain or weight loss failure
definition of early post-operation period
< 30 days post-op
nutrition: post-op– texture Texture progression
why?
To reduce vomiting and allow healing of anastomosis; To reduce vomiting and habituate patient to their new gastric pouch.
what is the texture progression will post-op pt experience? and how long at each stage?
- Clear fluids (1-3 days)
- Full fluids/puree (5 weeks)
- Solids (for life)
Portion progression: ½ cup to start, ↑ to 1 cup portions per meal/snack.
why choose very low calorie diet (VLCD) 2 weeks prior to surgery?
induce ketosis–> reduce liver size liver volume by decreasing intra-hepatic fat
- Improves visibility for surgeons - Reduced surgical risks
very low calorie diet (VLCD) for pre-op
- 800-900 calories Low carb ( <100 g/d, high protein, moderate fat)
Nutrition concerns:Vitamin & Mineral deficiencies— Doudenum
Ca Fe
Nutrition concerns:Vitamin & Mineral deficiencies— Jejunum
fat-solv vit: ADEK, folate
Nutrition concerns:Vitamin & Mineral deficiencies— terminal ileum
vitamin B12
Nutrition concerns: reduced Ca and Fe absorption– why
Removal of fundus
• Reduced
gastric acidity (hydrochloric acid - HCl) }
- may pass doudenum but probably not much / none absorption because there is no pancreatic enzyme
Vitamin & Mineral deficiencies are commonly in which type of BS?
RYGB: indicates more common deficiencies in BS
BPD-DS: common in BS, fat Vit deficiencies at greater risk
Why Vit B12 is a big concern although all paths go through ileum?
Vit B12 need IF to absob, but excluded fundus cannot produce IF
Why would prefer to using calcium citrate instead of calcium carbonate after bariatric surgery? (see slide 28)
1) it does not require stomach acid to aid in its absorption 2) less risk of kidney stones when supplementing with calcium citrate 3) less constipating compared to calcium carbonate 4) can be taken with or without a meal,
Vitamin & Mineral deficiencies: monitor & control
- daily compliance
- routine blood test
- adjust the dose if necessary
why protein status is one of the biggest concern?
- There must be a big lean body mass loss with the weight loss (even cause the reduction of metabolic rate)
- decreased dietary intake
- mal-absorption
Post-op: The causes of primary and secondary post-op protein malnutrition
1’ Primary protein malnutrition (PM) or protein-energy malnutrition (PEM)
Rare but at risk in all bariatric surgeries
Due to decreased oral intake/volume restriction
2’
Secondary PM or PEM:
type of surgeries: RYGB (rare) and BPD-DS (uncommon, but possible) :
Due to malabsorption
nutrition: late stage of post-op– texture Texture progression
Suggestions when eating and drinking
- well chewing
- drinking: no chug, just seeping
why need to chew food well and avoid drink with meal?
- Reduced grounding function of food in the stomach — may cause esophageal dysphagia.
- a big amount water will flush out the food without proper digestion.
if there is a patient showing symptom of vomiting, what is your first judgement?
- improper texture
- if chewing well when eating
- way of food preparation and eating: not too dry, be soft and moist; binging?; eat too much
- if the symptoms occur after 6 week post-op ( ususally on solid), refer to doc while reducing texture to applesauce
2 phases: dumping syndrome
early Phase : dizziness, nausea, weakness, rapid pulse, diarrhea —diarrhea is the most common symptom— 10-30min post meal; due to Due to rapid transit of hyperosmotic food into the jejunum (usually
simple sugars)
Late phase: hyperinsulinemic hypoglycemia— because body gives a shot of insulin to the exaggerate reaction to the undigested CHO
—- 1-3 hours post meal
the cause: dumping syndrome
Because of loss of sphincter, food easily slides into gut without proper breaking down
It happens with concentrated or simple liquid sugars (common in dessert and pure fruits)
NUTR internvention How to improve: dumping syndrome
re-form the portion of plate: protein more, CHO less
- If the case does not improve, recommend to other professionals
(ASMBS) protein recommendation
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
PDCAAS
to evaluate the quality of protein: based on the type of AA and how easy to digest by human
T/F use MSJ equation to calculate patient’s NRG requirement after BS
Although it is more accurate with obese population (BMI >30)
} …but does not appear to be applicable to a post-op bariatric
patient
what will cause diarrhea after BS
Lactose intolerance
} Dumping syndrome
} Sugar alcohols ( big liquid load of sugar)
the 6 key rules of dietary modification after BS
- Limit liquid calories
- but hydrate w/ Low kcal, low caffeine, low sugar, no carbonation
- a balanced plate: 1. protein 2. vegetables 3. grains
- Reduce frequency of eating out
- Decrease processed foods/simple sugars
- Decrease high fat foods
when to drink liquid w/ meal? if drink w/ with meal, what will happen?
15min before
or
30min after
quickly flush out food without proper digestion– > trigger hunger—> increase food intake—> possible weight gain?
if there is a patient reporting symptoms of shakiness, sweats,
nausea, and feeling very unwell, first judgement?
- is it onset by the last meal/ snack?
- type of food?
- diarrhea?
nesidioblastosis
hyperinsulinemic hypoglycemia
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. (3-6 mon post op)
But before diagonosing this prob, reassure the adequate protein intake and vitamin compliance.
A 46 year old woman who had a BPD-DS about 2 years
ago tells you that she has been losing a lot of hair over
the past 2 months and that she is afraid she’ll end up bald
if this continues.
What should you investigate?
- usual food intake
2. blood test
if the patient does not have any protein deficiency or vitamin deficiency but have severe hair loss, the possible reason?
Zinc deficiency or patient did not take the prescribed vitamin supplements ( changes to the other one for healthy population), etc
symptoms: zinc deficiency
Hair loss (6-9 mons post-op Dysgeusia
intervention: zinc deficiency
- Zinc supplementation: 60 mg elemental BID
- Monitor plasma zinc in bloodwork
- Suggest complete multivitamin to patient
when suggest complete multivitamin, what should pay attention: 3
Palatability, ease of swallowing pills, and cost
the 4 common causes of wt regain at post-op
Dietary habits - Increased calories: sugar and fat } Grazing: emotional eating } Not delaying fluids - Poorly controlled thyroid - New medications (weight promoting, antidepressants) - Stopped exercising
what is anastomotic leak
Most feared surgical complication (fatal)
} Occurs at suture lines
} Gastric contents leak into abdomen
NUTR care for in-patient with anastomotic leak
} TPN – total parenteral nutrition
who don’t prescribe EN for in-patient with anastomotic leak?
Bowel needs to be at rest to
encourage the healing process.
