Bariatric surgery Flashcards
1
Q
Indications for bariatric surgery?
A
- BMI of 40 kg/m2 or greater w/o comorbidities
- BMI of 35-39.9 with comorbidity: DM 2, OSA, HTN, hyperlipidemia, obesity hypoventilation syndrome, pickwickian syndrome (OSA+OHS), nonalcoholic steatohepatitis, pseudotumor cerebri, GERD, venous stasis disease, severe urinary incontinence, debiliation arthritis, impaired quality of life
- BMI of 30-34.9 and uncontrollable DM 2, metabolic syndrome (lack of evidence to support long term benefit in this group)
2
Q
CIs to bariatric surgery?
A
- hx of bulimia
- over 65 and under 18 (some exceptions made for under 18)
- for lipid and glycemic control
- for CV risk reduction
- untx major depression or psychosis
- binge-eating disorders
- current drug or ETOH abuse
- severe cardiac disease with prohibitive anesthetic risks
- severe coagulopathy
- inability to comply with requirements including (life long nutritional supplements) and dietary changes
3
Q
Preop assessment includes? Who is involved?
A
- psych
- medical
- anesthetic risk
- team approach: nutritionist, medical bari specialist, psychologist/psychiatrist, clinical nurse specialist, surgeon
4
Q
Goals and components for psych assessment?
A
- is pt able and willing to make necessary changes?
- ID of mental disorders
- social hx in regards to previous wt loss attempts, physical activity, substance abuse, compulsive eating
- does pt hav cognitive ability to do this and the support to carry it through?
- Components: behavioral, cognitive/emotional, current life situation, expectations
5
Q
Medical assessment for preop?
A
- complete H&P
6
Q
mechanisms of wt loss with surgery?
A
- restrictive
- malabsorptive
- both
7
Q
How do restrictive surgeries work?
A
- limit caloric intake by reducing stomach’s capacity:
resection
bypass
creation of proximal gastric outlet
surgeries: -vertical banded gastroplasty (not that common anymore) -laparoscopic adjustable gastric banding - sleeve gastrectomy
8
Q
Malabsorptive surgeries available? How do these work?
A
- jejunoileal bypass
- duodenal switch operation
- decrease the effectiveness of nutrient absorption by shortening length of fxnl smal intestine:
bypass small bowel absorptive surface area, diversion of biliopancreatic secretions that faciliate absorption
9
Q
Combo restrictive/malabsorptive surgeries?
A
- Roux-en-Y gastric bypass (RYGB) - most common
- biliopancreatic diversion
- bilipancreatic diversion with duodenal switch
10
Q
3 most common bari surgeries?
A
- RYGB - 47%
- sleeve gastrectomy - 28%
- laparoscopic adjustable gastric band - 18%
11
Q
What is the RYGB surgery? How common is it?
A
- create small gastric pouch (less than 30 ml) and an anastomosis to a roux limb of the jejunum that bypasses 75-150 cm of small bowel - restricts food and limits absorption
- major digestion and absorption of nutrients occurs in common channel where pancreatic enzymes and bile mix
- most commonly performed bari surgery in the US
- 47% of wt loss surgeries done in 2011
12
Q
How does RYGB promote wt loss?
A
- small pouch is restrictive
- malabsorption b/c of removed small bowel
- gastrojejunostomy can result in dumping syndrome with high sugar meals - lightheadedness, nausea, diaphoresis and/or abdominal pain, and diarrhea
- ghrelin inhibition (suppresses appetite)
- GLP-1 and CCK increased post bypass (may promote an anorectic state)
- CCK stimulates gastric emptying and appetite suppression
13
Q
What is the expected wt loss with RYGB?
A
- up to 70% of extra wt in 2 yrs
14
Q
What is sleeve gastrectomy? How common is it?
A
- majority of greater curvature of the stomach is removed and a tubular stomach is created. It has a small capacity and is resistant to stretching due to absence of the fundus and has few ghrelin producing cells
- 2nd most common wt loss surgery performed worldwide
- 28% of all procedures in 2011
- safer and technically less difficult to perfrom than RYGB
- new stomach is resistant to stretching w/o the fundus
15
Q
Wt loss mechanism of sleeve gastrectomy?
A
- restrictive
- alterations in gastric motility - slow transit time since fundus is removed
- decreased ghrelin levels
- increased GLP-1 and PYY (promotes less hunger)
16
Q
Expected wt loss from sleeve gastrectomy?
A
- 60% of excess wt lost in 2 yrs
17
Q
Laparoscopic adjustable gastric band surgery - how common, and what is it? How safe is this?
A
- 18% of bari surgeries done in 2011
- soft silicone ring connected to an infusion port placed in subq tissue
- ring is inflated with saline to cause variable degrees of restriction
- goal of band adjustments: allow a cup of dried food, satiety for at least 1.5-2 hrs after a meal
- lowest mortality rate among bariatric surgeries
- replaced the earlier procedure vertical banded gastroplasty that had higher incidence of complications
- band is adjustable to allow more food and liquids in the future if needed
- Purely restrictive wt loss mechanism
18
Q
Expected wt loss from lap band?
A
- 50-60% of excess wt lost at 2 yrs
19
Q
What bari surgery is recommended for diabetes pts?
A
- gastric bypass - change in hormones, more favorable outcome
20
Q
Post surgical diet?
A
- varies depending on procedure
- usually have a liquid diet that progresses to soft then full diet over a period of weeks to months
21
Q
wt and BP monitoring post procedure?
A
- monitor both at q f/u
- watch for hypotension (esp if persistent vomiting)
- check BP and wt q 4-6 wks for the first 6 months then at 9 and 12 for month, and then annually
22
Q
impt macronutrient needs for postop?
A
- protein is super impt, carbs and fats
- same among diff procedures
- RYGB doesn’t cause sig macronutrient deficiences
23
Q
impt micronutrients to supplement postop?
A
- lap band: folate deficiences (can’t eat as many veggies)
- sleeve gastrectomy: B12 (removing parietal cells in fundus - IF)
- RYGB: Vit A, D, E, K, B1 (thiamine), B12, iron, copper, zinc, folic acid, biotin, selenium
24
Q
What labs should be checked at 3, 6, 12 months and then annually?
A
- CBC
- CMP
- iron studies, ferritin
- B12
- lipids
- 25 OH-Vit D, PTH
- thiamine
- folate
- zinc
- copper
25
Med management post surgery?
- change meds from delayed release to immediate release - crush or liquid form
- in general should DC oral antidiabetic meds and use insulin therapy for glycemic control
- usually can DC antireflux meds except after sleeve gastrectomy reflux sxs increase
- OCPs may be less effective
- in general avoid NSAIDs - esp in pts who have had RYGB, they have very little stomach area and are set up for ulcers
26
What factors affect glycemic control post surgery?
- 400-800 kcal diet/day for 1st month
- avg wt loss in first month is 20-40 lbs
- improvement in DM control happens regardless of amt of wt lost
- DM remission can occur in first month - but in 1/3 of pts recurs at 5 yr mark
- exposure of distal jejunum to undigested nutrients - increased peptide YY, GLP-1, and GIP
27
Late complications of bari surgery (post 30 days)?
- cholelithiasis (most common in pts who have lost a lot of wt)
- nutritional deficiencies
- neuro complications
- psych complications
28
Complications of RYGB?
- gastric remnant distension
- stomal stenosis
- internal hernias
- short bowel syndrome
- dumping syndrome
- metabolic/nutritional derangements
- renal failure
- post-op hypoglycemia
- change in bowel habits
- failure to lose wt and wt regain
- ventral incisional hernias
29
```
What complication would present with these sxs:
upper abdominal pain
hiccups
LUQ tympany
shoulder pain
abdominal distension
tachycardia
SOB
large gastric bubble on xray
```
- how common is this? How severe?
gastric remnant distenstion
- rare
- may be fatal
- gastric pouch severe distension secondary to mechanical obstruction or paralytic ileus
- progressive distension and rupture
- tx: emergent surgery
- RYGB complication
30
```
Which complication may present with these sxs:
several weeks post op -
N/V
dysphagia
GE reflux
inability to tolerate oral intake
```
workup and tx?
stomal stenosis: upper problem - either before or after gastric pouch
- 6-20% of pts
- narrowing at anstomosis (pouch to rouch limb)
- work up: endoscopy or UGI series
- tx: endoscopic balloon dilation
- RYGB complication
31
What are marginal ulcers? Where do they occur, What are the causes?
- acid injury to the jejunum or assoc with gastrogastric fistula
- occur near gastrojejunostomy
- may present with nausea, pain, upper GI bleed
- 0.6-16% of pts
- causes:
poor tissue perfusion (sutures too tight, didn't heal right)
excess acid
NSAIDs
H. pylori
smoking
- RYGB complication
32
Sxs, dx and tx of marginal ulcers?
- sxs: Nausea, pain, bleeding, and/or perforation
- dx: upper endoscopy
- tx:
acid suppression
sucralfate
DC NSAIDs
DC smoking
test and tx H pylori
33
```
What complication would present with these sxs:
RUQ pain
R shoulder pain or pain in R upper back
N/V
fever
pain may worsen with deep inspiration
pain may last longer then 6 hrs and start postprandia
tender RUQ on exam
```
Dx, TX?
- acute cholecystitis/cholelithiasis
- 38% of pts within 6 months of surgery
- can be prevented by post op ursodiol
- dx: US
- Tx: surgical removal of gallbladder
34
Pt presents with abdominal pain following RYGB, and on CT scan - swirled appearance of mesenteric vessels with mesenteric edema, most likely cause?
- short bowel syndrome: hernia through mesentery which leads to obstruction of vessels
- results in severe micro and macronutrient deficiencies
- in severe cases may reqr intestinal transplantation
35
What complication presents with these sxs:
| 15 min postprandial - development of colicky abdominal pain, diarrhea, nausea and tachycardia
- early dmping syndrome
- up to 50% of pts develop either early or late dumping syndrome
- prominent post ingestion of simple carbs
- quick spike in blood sugar triggers this, main sx: is immediate diarrhea
36
When does late dumping syndrome occur? Sxs?
- 2-3 hrs after a meal
- dizziness, fatigue
- diaphoresis and weakness
37
What complication would a pt have if they complain of having blackouts and seizures?
- - severe hypoglycemia
- may be secondary to insulinoma
- may be secondary to iselt cell hypertrophy
- slowing food transit time may resolve the sxs (acarbose)
38
What bowel habit changes are common post surgery?
- diarrhea or loose stools are common post RYGB
| - constipation is common post gastric banding
39
What may be wrong if the pt complains about not losing wt, or complains of gaining wt?
- maladaptive eating patterns
- gastrogastric fistula
- gradual enlargement of gastric pouch
- dilation of gastrojejunal anastomosis
40
Complications from gastric banding?
- pouch dilation
- stomal obstruction
- band slippage, infection or erosion
- incisional hernias
- port-tubing disconnections
- port infections
- esophagitis
- esophageal dilation
41
What would these sxs indicate: persistent nausea, vomiting and inability to tolerate secretions or oral intake
- how common is this, Dx, tx?
- stomal obstruction
- up to 14%
- can be acute (shortly after surgery)
- may be secondary to edema or due to band being too tight
dx: UGI
tx: NG tube to decompress until edema subsides or surgery for band revision (risk is esophageal perf if tissue is necrotic)
42
What complication is this:
| infection, failure of wt loss, N/V, epigastric pain, hematemesis? How common is this, dx, Tx?
- band erosion
- up to 7%
- occurs at mean of 22 months
- dx: endoscopy
- tx: surgical removal
43
Most common sleeve gastrectomy complications?
- GERD
- bleeding
- stenosis of stoma
- leaks
44
Most serious complication of SG? Usually do to?
- gastric leaks
- occurs in up to 5.3% of pts
- leaks usually due to local factors that impede healing:
inadeq blood supply to staple line, gastric wall heat ischemia - too much cautery done
there can be high intragastric pressure - over-eating
