SELECTED TOPICS IN BARIATRIC SURGERY
Selections from the 4th Annual Surgery of the Foregut Symposium, presented February 21-23, 2005, by the
Cleveland Clinic Florida
| BANDING OR BYPASS: HOW DO WE MAKE THE CHOICE? —Samuel Szomstein, MD, Associate Director, Bariatric
Institute and Section of Minimally Invasive Surgery, Cleveland Clinic Florida, Weston
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| Mortality rate: gastric banding—≤0.5% (0% in some series); gastric bypass—≤1% (2%-3% in some series)
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| Early complications: banding—gastric perforation; bleeding; food intolerance (most common immediate postoperative
complication); wound infection; pneumonia; deep venous thrombosis (DVT) negligible; bypass—leak (1%-3%);
bleeding (0.5%-2%); bowel obstruction (1%-3%); wound infection, pneumonia, and DVT <1%
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| Late complications: bypass—less frequent and less dramatic than with banding; stenosis most common (≈6%; range
≤20%); marginal ulcers uncommon; cholelithiasis (≈3%); small bowel obstruction (1%); incisional hernias (0.2%-2%);
banding—food intolerance or noncompliance to band (≈13%); band slippage (2.2%-8%); pouch dilatation; band erosions;
port complications; reoperation rate 2% to 41%
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| Weight loss: banding—30% to 58% at 3 to 5 yr; 10% to 35% for superobese patients; bypass—62% to 77%; 60% to
75% for superobese patients
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| Advantages of gastric banding: short hospital stay (speaker recommends overnight stay and follow-up with Gastrografin
study); quick recovery; good results; adjustable (can be tailored to patient’s needs and progress); reversible (relatively
easy operation); low-complexity procedure; can be converted to bypass
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| Advantages of gastric bypass: extensive experience with procedure; long-term follow-up shows very good results;
follow-up less intensive (patients can be seen 4 to 5 times in 12 mo, provided they have contact with nutritionist); foolproof
(patients cannot eat around bypass); dumping syndrome—does not occur with banding; acts as safety
mechanism that promotes weight loss; 1 in 4 patients with high carbohydrate/sugar intake experience dumping syndrome
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| Resolution of comorbidities: bypass—improves diabetes and hypertension; banding—potentially improves diabetes
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| Disadvantages of gastric banding: very high reoperation rate; patients can get lost during follow-up; exposure of surgeon
to x-rays; sense of reversibility increases likelihood of failure; slow reward
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| Disadvantages of gastric bypass: complex surgery; associated with some mortality (≈0.5%); metabolic disturbances;
essentually irreversible; steep learning curve
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| Indications for gastric banding: adolescent and elderly patients; patients with inflammatory bowel disease (Crohn’s disease
or ulcerative colitis); patients unable to cope with potential complications of bypass surgery; failed gastric bypass (band
can restore restriction after loss of gastrojejunostomy [GJ] stretch)
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| Prophylactic gastric banding: speaker believes prophylactic gastric banding suitable for some type I obese patients
unsuccessful with conventional diets
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| Superobese patients: speaker does not use band in patients with body mass index (BMI; weight [kg]/height [m2]) >50
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| PREVENTION OF ACUTE VENOUS THROMBOEMBOLISM —Michael Schweitzer, MD, Assistant Professor of
Surgery, Johns Hopkins University School of Medicine, Baltimore
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| Predisposing factors for venous thromboembolism (VTE): morbid obesity; general anesthesia; age >40 yr; history
of DVT or pulmonary embolism (PE); smoking; speaker advocates cessation of hormone therapy 1 mo before surgery;
pregnancy; cancer; trauma; orthopedic surgery
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| Intraoperative factors contributing to thrombosis: steep reverse Trendelenburg’s position; pneumoperitoneum,
used during laparoscopic procedure, increases intra-abdominal pressure; longer operative time increases risk for DVT
and PE; increased inflammatory mediators after open surgery
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| (Enoxaparin and Cancer) ENOXACAN I trial: patients undergoing abdominal or pelvic surgery randomized to
enoxaparin qd or unfractionated heparin tid; patients assessed with venography; results—slight decrease in incidence
of VTE in enoxaparin group
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| ENOXACAN II trial: after undergoing abdominal or pelvic surgery, 505 patients received enoxaparin 40 mg qd for 8
days, then randomized to enoxaparin or placebo for remainder of month; venography performed at end of month;
results—enoxaparin reduced incidence of VTE at 1 mo (benefit remained at 3 mo and comparable to that seen in orthopedic
surgery)
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| Incidence of DVT: Mason et al (1992)—National Bariatric Surgery Registry data; incidence of DVT 0.35%, PE
0.03%; average BMI 44
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| 1998 American Society for Bariatric Surgery (ASBS) survey: survey of 128 members; 61% of patients treated with
open gastric bypass, and 1.6% treated laparoscopically; most patients received low-dose heparin and sequential compression
device (SCD); incidence of DVT 2.63%, PE 0.95%;
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| Multicenter study: in 2246 cases of laparoscopic gastric bypass, incidence of clinical DVT and PE both 0.7%; mortality
rate 0.1%; prophylaxis—all centers used low-molecular-weight heparin or unfractionated heparin tid; SCDs routinely
used by 4 of 5 surgeons; extended prophylaxis—used by 4 of 5 surgeons; speaker uses extended prophylaxis
for patients with severe chronic venous stasis disease, patients with high BMI, and wheelchair-bound patients
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| Inferior vena cava (IVC) filter placement: often used in patients with history of PE or DVT, obesity hyperventilation
syndrome, severe venous stasis, or high BMI
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| Anti-factor Xa levels: study—enoxaparin 30 mg bid vs 40 mg bid; peak level reached 4 hr after enoxaparin administration;
target range for anti-factor Xa 0.2 to 0.5 IU/mL (>1 IU/mL associated with significant increase in bleeding
events); 2 patients in 30-mg group reached target range; 6 of 29 patients in 40-mg group reached target range; anti-factor
Xa levels do not correlate with clinical outcome
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| Fatal PE after bariatric surgery: Sapala et al—in >5500 patients, fatal PE rate 0.21%; risk factors included venous
stasis disease, BMI >60, truncal obesity, and obesity hyperventilation syndrome; Sugerman et al—severe venous stasis
disease associated with 10-fold increase in mortality rate and higher PE rate
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| Summary: all patients undergoing bariatric surgery require prophylaxis; preoperative dosing makes sense; correct
doses unclear; consider extended prophylaxis; IVC filters indicated in some patients
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| ENDOSCOPIC INTRALUMINAL PROCEDURES AFTER BARIATRIC SURGERY —Dr. Schweitzer
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| Gastroplication devices: EndoCinch (Bard), Endoscopic Suture Device (ESD; Wilson-Cook), and Full-Thickness Plicator
(NDO Surgical) approved by Food and Drug Administration (FDA) for treatment of gastroesophageal reflux disease;
short-term results; expensive procedures (facility, endoscopist, and device fees ≈$3000); EndoCinch—fits on
standard gastroscope; tissue sucked in at gastroesophageal (GE) junction; needle carrying suture passes through tissue;
clip device acts as knot; Full-Thickness Plicator—does not use suction; corkscrew pulls tissue in; made for retroflexion
inside stomach; ESD—developed from laparoscopic suture device; one instrument places suture and one places
tie-knot (metal clip); uses suction to pass needle through tissue
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| Preventing weight gain after bariatric surgery: weight gain possibly due to stoma dilation or gastric pouch dilation;
partition breakdown in open procedure with TA or PI stapler needs to be corrected; poor eating behavior primary issue
(“nothing beats the potato chip”); band or silicone ring placed around stomach may solve problem, but may prevent
patient from eating solid food and force them onto more carbohydrate-based diet; study—75% of patients lost weight
with endoscopic sclerotherapy of GJ; results short-term; average weight loss 5.8 kg; dietary discretion after gastric bypass
most crucial point; suture plication with ESD—need to select patients carefully; speaker believes patients with
bad eating habits not likely to benefit
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| Limitations: bulky equipment; depth of suture inconsistent; flexibility issues; insurance reimbursement; expensive
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| LATE COMPLICATIONS OF BARIATRIC SURGERY —Robert E. Brolin, MD, Director of Bariatric Surgery, University
Medical Center at Princeton; Adjunct Professor of Surgery, University of Pittsburgh Medical Center
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Small Bowel Obstruction (SBO)
| Incidence: relatively rare after purely restrictive procedure; incidence after open Roux-en-Y gastric bypass 1% to 3%;
increased incidence with laparoscopic procedure using retrocolic approach
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| Presentation: nausea; vomiting (may be less prominent because of small upper gastric pouch); colicky abdominal pain;
obstipation; abdominal distention; severe steady pain in presence of nausea, vomiting, and obstipation suggests strangulation
or intussusception and warrants early operative intervention
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| Radiologic evaluation: begin with plain abdominal x-rays; occasionally see classic dilated loops of small bowel with
stepladder pattern; abdominal computed tomography (CT) effective diagnostic test, although can miss internal hernias
and afferent limb obstruction; Gastrografin frequently resolves partial SBO; CT renders upper gastrointestinal (GI)
barium studies obsolete
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| Literature review: Champion et al—10-fold increased incidence of SBO with retrocolic approach in conjunction with
laparoscopic Roux-en-Y gastric bypass, compared to antecolic approach; internal hernias most common cause, adhesions
second; closure of mesenteric defects did not decrease incidence of SBO postoperatively; Felix et al—3-fold increased
incidence of SBO with retrocolic approach, compared to antecolic approach; adhesions most common cause,
internal hernias second; Gagner et al—over short period, incidence of internal hernias associated with antecolic laparoscopic
Roux-en-Y gastric bypass increased from 3.3% to 6.4%; 8 major complications and 1 fatality in 47 patients
undergoing operative treatment; mesenteric closure reduced but did not eliminate SBO; Fox et al—2% of >1400 patients
had unusual cases or etiologies of SBO; very high incidence of small bowel resection due to associated necrosis
of bowel; internal hernias most common cause; 4 cases of intussusception
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| Afferent or biliopancreatic limb obstruction: rare cause of SBO after Roux-en-Y gastric bypass; difficult diagnosis
due to vague symptoms; symptoms—distention and nausea common; vomiting and obstipation not common (diarrhea
more likely present); in speaker’s experience, diarrhea and bloating most prominent symptoms; etiologies—
adhesions; internal hernia; jejunojejunostomy stricture; diagnosis—need high index of suspicion; CT best test; plain
radiographs frequently unremarkable; laboratory tests (eg, elevated liver function, amylase, anemia, hypoproteinemia)
can corroborate suspicions
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| Summary: “patients with small bowel obstruction after gastric bypass may present with vague complaints and confusing
laboratory and nonspecific findings on x-ray; delayed diagnosis can have catastrophic consequences; CT imaging
can be lifesaving and should be obtained in all gastric bypass patients with abdominal pain, particularly when other
parameters seem normal; unexplained abdominal pain should prompt exploration”
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Marginal Ulcer
| Presentation: substernal pain; bleeding; free perforation rare; increased incidence in smokers and patients who abuse
nonsteroidal anti-inflammatory drugs (NSAIDs); in speaker’s experience, associated with cyclooxygenase-2 (COX-2)
inhibitors; patients can present with delayed vomiting
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| Incidence: Sugerman et al—12.5%; MacLean et al—16% (many patients had gastrogastric fistulae)
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| Physiology: jejunal mucosa very sensitive to gastric acid; extremely small quantity of acid produced in small gastric
pouches <30-mL capacity; serum gastrin levels low-normal or subnormal
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| Diagnosis: upper endoscopy best diagnostic tool; gastrogastric fistula common predisposing factor and better seen using
upper GI contrast study
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| Treatment: majority of patients respond to medical treatment (H2 blockers or proton pump inhibitors); operative intervention
may be required for intractable patients, eg, heavy smokers, those taking antiarthritis medications, and those
with gastrogastric fistulae
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| Operative management: essential to excise ulcer; subacute inflammation often present; speaker has not used laparoscopic
procedure; if ulcer resized, need to revise GJ; in cases of gastrogastric fistula, need to restaple stomach with
transection; vagotomy—utility of vagotomy not demonstrated; speaker believes procedure difficult to perform transabdominally
because of inflammation; transthoracic vagotomy unlikely adequate treatment without excision of ulcer
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Differential Diagnosis of Late Vomiting
| Summary: vomiting in presence of persistent diarrhea indicates gastroenteritis; vomiting with colicky abdominal pain
and obstipation indicates SBO until proven otherwise; vomiting in absence of intestinal symptoms indicates mechanical
gastric outlet obstruction or overeating
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Educational Objectives
| The goal of this program is to educate the listener about selected topics in bariatric surgery. After hearing and assimilating
this program, the clinician will be better able to:
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 | 1. Contrast gastric bypass and gastric banding.
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| 2. Identify patients at risk for venous thromboembolism after bariatric operations.
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| 3. Discuss postoperative endoluminal intervention in patients undergoing bariatric operations.
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| 4. Review the incidence and clinical presentation of small bowel obstruction after bariatric operations.
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| 5. Review the clinical presentation and diagnosis of marginal ulcers after bariatric operations.
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Discussed on This Program
Enoxaparin sodium [Lovenox]
Heparin sodium injection
Suggested Reading
Bergqvist D et al; ENOXACAN II Investigators: Duration of prophylaxis against venous thromboembolism with
enoxaparin after surgery for cancer. N Engl J Med 346:975, 2002; Brolin RE: Gastric bypass. Surg Clin North Am
81:1077, 2001; Buchwald H et al: Bariatric surgery: a systematic review and meta-analysis. JAMA 292:1724, 2004;
Chadalavada R et al: Comparative results of endoluminal gastroplasty and laparoscopic antireflux surgery for the
treatment of GERD. Surg Endosc 18:261, 2004; Champion JK, Williams M: Small bowel obstruction and internal
hernias after laparoscopic Roux-en-Y gastric bypass. Obes Surg 13:596, 2003; Chapman AE et al: Laparoscopic adjustable
gastric banding in the treatment of obesity: a systematic literature review. Surgery 135:326, 2004; Chuttani R:
Endoscopic full-thickness plication: the device, technique, pre-clinical and early clinical experience. Gastrointest Endosc
Clin N Am 13:109, 2003; Filip JE et al: Internal hernia formation after laparoscopic Roux-en-Y gastric bypass for
morbid obesity. Am Surg 68:640, 2002; Fobi MA et al: Choosing an operation for weight control, and the transected
banded gastric bypass. Obes Surg 15:114, 2005; Haider M et al: Endoluminal gastroplasty: a new treatment for gastroesophageal
reflux disease. Thorac Surg Clin 15:385, 2005; Higa KD et al: Internal hernias after laparoscopic Roux-
en-Y gastric bypass: incidence, treatment and prevention. Obes Surg 13:350, 2003; Higa KD et al: Complications of
the laparoscopic Roux-en-Y gastric bypass: 1,040 patients--what have we learned? Obes Surg 10:509, 2000; Miller
MT, Rovito PF: An approach to venous thromboembolism prophylaxis in laparoscopic Roux-en-Y gastric bypass surgery.
Obes Surg 14:731, 2004; O'Brien PE, Dixon JB: Lap-band: outcomes and results. J Laparoendosc Adv Surg
Tech A 13:265, 2003; Podnos YD et al: Complications after laparoscopic gastric bypass: a review of 3464 cases. Arch
Surg 138:957, 2003; Provost DA: Laparoscopic adjustable gastric banding: an attractive option. Surg Clin North Am
85:789, 2005; Sarker S et al: Early and late complications following laparoscopic adjustable gastric banding. Am Surg
70:146, 2004; Scholten DJ et al: A comparison of two different prophylactic dose regimens of low molecular weight
heparin in bariatric surgery. Obes Surg 12:19, 2002; Schweitzer M: Endoscopic intraluminal suture plication of the
gastric pouch and stoma in postoperative Roux-en-Y gastric bypass patients. J Laparoendosc Adv Surg Tech A 14:223,
2004; Shepherd MF et al: Unfractionated heparin infusion for thromboprophylaxis in highest risk gastric bypass surgery.
Obes Surg 14:601, 2004; Shepherd MF et al: Heparin thromboprophylaxis in gastric bypass surgery. Obes Surg
13:249, 2003; Srikanth MS et al: Computed tomography patterns in small bowel obstruction after open distal gastric
bypass. Obes Surg 14:811, 2004.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue, the
following has been disclosed: Dr. Schweitzer is a consultant for Aventis Pharmaceuticals and US Surgical.
Drs. Szomstein, Schweitzer, and Brolin were recorded February 22, 2005, at the 4th Annual Surgery of the Foregut
Symposium, sponsored by the Cleveland Clinic Florida and held in Coral Gables, Florida. The Audio-Digest Foundation
thanks the speakers and the Cleveland Clinic Florida for their cooperation in the production of this program.
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