Bariatric Surgery
Roberto C. Mirasol, MD, FPCP, FPSEM
Obesity and Weight Management Center
St. Luke’s Medical Center
Bariatric
Surgery
• Indications
1. BMI >40 kg/m2 or
BMI 35–39.9 kg/m2 and
life-threatening cardiopulmonary
disease, severe diabetes, or
lifestyle impairment
2. Failure to achieve adequate weight loss with nonsurgical treatment
• Contraindications
1. History of noncompliance with medical care
2. Certain psychiatric illnesses: personality disorder, uncontrolled
depression, suicidal ideation, substance abuse
3. Unlikely to survive surgery
NIH Consensus Development Panel. Ann Intern Med 1991;115:956.
CLINICAL PRACTICE RECOMMENDATIONS, 2009
ADA
• Bariatric surgery should be considered for
adults with BMI 35 kg/m2 and type 2 diabetes,
especially if the diabetes is difficult to control
with lifestyle and pharmacologic therapy. (B)
• Patients with type 2 diabetes who have
undergone bariatric surgery need life-long
lifestyle support and medical monitoring. (E)
Bariatric Surgery Stats
1995 the number of bariatric surgeries
performed was well over 20000
2003 - 103,000
2004 - 144,000
Average age of patient – 30 years old
Length of Hospital Stay – 3.9 days
Bariatric surgeons – increased by 500%
Complication rate – 10%
Deaths <1%
CDC, 2006
Current Bariatric Surgical Procedures
Classification
Procedure
Gastric restriction
• Adjustable Gastric Banding
Primarily restrictive and
partially malabsorptive
• Roux-en-Y Gastric Bypass
Primarily malabsorptive
and partially restrictive
 Biliopancreatic diversion
with duodenal switch
 Biliopancreatic diversion
 Distal gastric bypass
Gastric Bypass Procedure
A small (10–30 mL) gastric
pouch is anastomosed to a
Roux limb of jejunum.
Increasing the length
of the Roux limb increases
malabsorption and
weight loss.
Long-term Effect of Gastric Bypass
Surgery on Body Weight
Weight Loss
(% of Excess Weight)
0
20
40
60
80
100
0
2
BMI (kg/m2): 50
Poiries et al. Ann Surg 1995;222:339.
4
6
8
10
Years After Surgery
34
35
12
14
35
Randomized, Controlled Trial
Comparing Open With Laparoscopic
Gastric Bypass
• Both procedures had
– Similar weight loss
– Similar incidence of anastomotic leaks
– Equivalent costs
• Laparoscopic procedure had
– Less wound complications (infection and hernia)
– Increased late anastomotic strictures
– Less blood loss
– Shorter hospital stay
– Faster recovery
– Faster improvement in quality-of-life
Nguyen et al. Ann Surg 2001;234:279.
Weight Loss With Gastric Bypass Procedure
vs. Vertical Banded Gastroplasty
Decrease in Excess Weight (%)
90
70
Gastric bypass
50
Vertical banded gastroplasty
30
10
0
6
12
18
24
Time (months)
Sugerman et al. Ann Surg 1987;205:613.
30
36
Laparoscopic Adjustable Gastric Banding
LapBandTM
Access port (reservoir)
Gastric Band
Connection tubing
Silicone band placed around
upper stomach to create a small
pouch. Outlet diameter can be
changed by infusing or
withdrawing saline from port.
American Society for Metabolic and Bariatric Surgery, www.asbs.org
LAP BAND
Laparoscopic Adjustable Gastric Banding Produces
Greater Weight Loss than Comprehensive Medical Therapy*
in Patients with Class I Obesity (BMI 30-35 kg/m2)
0
Weight Loss, %
-5
-10
-15
-20
Surgical
-25
-30
Nonsurgical
Baseline
6 mo
12 mo
*(VLCD, behavioral modification, and pharmacotherapy)
Obrien et al. Ann Intern Med. 2006;144:625-33
18 mo
24 mo
Biliopancreatic Diversion With
Duodenal Switch
Sleeve gastrectomy with rerouting
of small intestine through “nutrient
limb” and “biliopancreatic limb.”
Digestion and absorption are
limited to 100 cm “common
channel” of terminal ileum.
Causes marked weight loss, but
can lead to significant nutritional
deficiencies.
Marceau P. et al. World J Surg 1998;22:947-54.
Effect of Different Bariatric Surgical
Procedures on Weight Loss
Procedure
Approximate
Loss of Excess
Weight (%)
Laparoscopic gastric banding
45–65
Gastric bypass procedure
55–65
Biliopancreatic diversion
with duodenal switch
60–75
Klein et al. Gastroenterology. 2002;123:882-932
Incidence of Gallstone Formation
(% subjects/wk)
Relationship Between Rate of Weight
Loss and Gallstone Formation
3
2
Data reported from individual studies
1
0
0
1
0.5
1.5
Rate of Weight Loss (kg/wk)
Weinsier et al. Am J Med 1995;98:115.
2
2.5
Complications of Bariatric Surgery
All procedures:
•
•
•
•
•
•
•
•
•
Atelectasis and pneumonia
Deep vein thrombosis
Pulmonary embolism
Wound infection
Gastrointestinal bleeding
Gallstones
Failure to lose weight
Intractable vomiting/kwashiorkor (B1)
Mortality (0.1%–2%)
Gastric bypass:
•
•
•
•
•
•
•
Anastomotic leak with peritonitis
Stomal stenosis
Marginal ulcers
Staple line disruption
Nutrient deficiencies (iron, calcium, folic
acid, vitamin B12)
Dumping syndrome
Small bowel obstruction
– Internal hernia
– Adhesions
Gastric banding procedure:
•
•
•
•
•
•
Band slippage
Band erosion
Esophageal dilatation
Band or port infections
Port disconnection
Port displacement
Biliopancreatic diversion:
•
•
•
•
•
•
Anastomotic leak with peritonitis
Protein-calorie malnutrition
Calcium, iron, folic acid, fat soluble
vitamin (A,D,E,K) deficiencies
Dehydration
Steatorrhea
Small bowel obstruction
– Internal hernia
– Adhesions
Relationship Between Surgical Experience and
Perioperative Mortality in Gastric Bypass Surgery
7%
Thirty Day Mortality
6%
5%
125 case lifetime bariatric
surgery experience
4%
3%
2%
1%
0%
0
50 100 150 200 250 300 350 400 450 500 550 600 650
Chronological case order per surgeon
D Flum et al. J Am Coll Surg 199:543, 2004
Patients with Normal Fasting
Blood Glucose and HbA1c
After Surgery (%)
Gastric Bypass Surgery Improves Glycemic Control in
Impaired Glucose Tolerance or Type 2 Diabetes
100
75
50
25
0
Patents with
Type 2 Diabetes
Pories et al. Ann Surg 1995;222:339.
Patients with
IGT
Incidence of Type 2 Diabetes
(% Patients)
Prevention of Type 2 Diabetes at 8 Years
After Bariatric Surgery (94% Restrictive)
20.0
16.0
Control
Bariatric surgery
18.5
12.0
8.0
4.7
3.6
4.0
0.0
0.0
2
8
Follow-up After Surgery (y)
Control
Initial BMI (kg/m2)
41  5
Weight change at year 8: 1  11%
Sjostrom et al. Hypertension 2000;36:20.
Surgery
41  4
-16  12%
Ratio of Recovery (% of subjects)
Effect of Bariatric Surgery on Obesity-related
Metabolic Complications
100
Control
Surgery
72
80
62
60
46
36
34
40
21
13
21
19
22
24
11
20
0
2 yr
10 yr
Diabetes
Sjöström: N Engl J Med 2004;351:2683.
2 yr
10 yr
Hypertension
2 yr
10 yr
Hypertriglyceridemia
(Brunt et al. system)
Histology score
Effect of Gastric Bypass Surgery-induced
Weight Loss on Liver Histology
3
Before GBS
1 Yr after GBS
2
1
0
Steatosis
Inflammation
Klein S. et al. Gastroenterology 130:1564, 2006
Fibrosis
Long-term Survival: Canada
7
Rel. Risk = 0.11 (.04-.27)
% Mortality
6
89% reduction in risk of
death over 5 years
5
4
3
2
1
0
Control
Christou et al. Ann Surg 2004;240:416-424
Bariatric Surgery
Major Obesity-related Comorbidities That Have Been Improved
by Bariatric Surgery
•
•
•
•
•
•
•
•
Type 2 diabetes
Hypertension
Obstructive sleep apnea
Obesity hypoventilation
GERD
NALD, NASH
Pseudotumor cerebri
Depression
•
•
•
•
•
•
•
•
•
Dyslipidemias
Coronary artery disease
Cardiac dysfunction
Venous stasis disease
Polycystic ovary syndrome
Infertility
Cancers
Degenerative joint disease
Quality of life
GLP-1 and GIP Are the Two Major
Incretins
GLP-1
GIP
• Produced by L cells mainly located
in the distal gut (ileum and colon)
• Stimulates glucose-dependent
insulin release
Other effects
• Suppresses hepatic glucose output
by inhibiting glucagon secretion in
a glucose-dependent manner
• Inhibition of gastric emptying;
reduction of food intake and
body weight
• Enhances beta-cell proliferation
and survival in animal models
and isolated human islets
• Produced by K cells in the proximal
gut (duodenum)
• Stimulates glucose-dependent
insulin release
• Minimal effects on gastric
emptying; no significant effects
on satiety or body weight
• Potentially enhances beta-cell
proliferation and survival in
islet cell lines
GLP-1=glucagon-like peptide-1; GIP=glucose-dependent insulinotropic polypeptide.
Drucker DJ. Diabetes Care. 2003;26:2929–2940; Ahrén B. Curr Diab Rep. 2003;3:365–372; Drucker DJ. Gastroenterology. 2002;122:
531–544; Farilla L et al. Endocrinology. 2003;144:5149–5158; Trümper A et al. Mol Endocrinol. 2001;15:1559–1570; Trümper A et al.
J Endocrinol. 2002;174:233–246; Wideman RD et al. Horm Metab Res. 2004;36:782–786.
Nonincretin Gut Peptides
• Peptide YY (PYY)
– Secreted by the L cells of the distal intestine
– Present in 2 molecular forms: PYY(1-36) and PYY
(3-36), a cleavage product
– PYY increases satiety and delays gastric emptying
through neuropeptide Y-receptor subtypes in the
central and peripheral nervous system
– IV PYY(3-36) increases satiety and decreases food
intake in humans
Nonincretin Gut Peptides
• GHRELIN
– Secreted by gastric fundus and proximal small intestine
and acts on the hypothalamus to regulate appetite
– Inhibits insulin secretion by a paracrine mechanism
– Systemic ghrelin levels increase before a meal and
decrease afterward
– Ghrelin stimulates appetite and food intake and
suppresses energy expenditure and fat catabolism
– Inversely proportional to body weight
– Weight loss increases ghrelin levels suggests that ghrelin
affects long term regulation of body weight
PROPOSED MECHANISMS FOR
IMPROVED GLYCEMIC CONTROL
AFTER BARIATRIC SURGERY
Effects of Decreased Caloric Intake
on Fasting Glycemia
• Decreased caloric intake affects glucose
metabolism
• Rate of diabetes remission are not the same
– Complete remission within days of intestinal
bypass procedures (Porries, 1995)
– Takes months to occur in LAGB (Dixon, 2008)
RUBINO EXPERIMENTS
• Goto- Kakizaki Rats- non obese animal model
for diabetes
DJB (duodenal-jejunal bypass) – less
fasting and postprandial
hyperglycemia than control
Weight loss by caloric restriction –
glycemic control did not improve
HINDGUT HYPOTHESIS (LOWER
INTESTINAL HYPOTHESIS)
• Intestinal rearrangement speeds the delivery
of nutrients to the distal intestines
• Causes exaggerated GLP-1 and PYY levels and
improves glucose tolerance and insulin
secretion
Cummings, et al, 2007
FOREGUT EXCLUSION THEORY
(UPPER INTESTINAL HYPOTHESIS)
Bypassing gut prevents the secretion of a
“putative signal” that promotes insulin
resistance and Type 2 DM.
• Stomach sparing DJB vs Gastrojejunostomy
(leaves nutrient flow in the proximal intestine
intact)
• Bypass of proximal gut prevents secretion
“Anti-incretin factor” or “decretin”
• May be implicated in the pathogenesis of
diabetes
Gut Peptide Response to Different
Bariatric Surgical Procedures*
HORMONE
Cell Type
(Location)
Effect on
Insulin
Secretion
BPD
RYGB
LAGB
Ghrelin
X/A cells
Stomach
Decrease
Increase
Increase/
Decrease
Increase/
No Change
GIP
K cells
duodenum
Increase
Decrease
Decrease
No change
GLP-1
L cells
Distal ileum
Increase
Increase
Increase
No change
Peptide YY
L cells
Distal ileum
Decrease
Increase
Increase
No change
*Folli, 2007
BARIATRIC SURGERY IN ST LUKE’S
PATIENT PROFILE*
MALE
FEMALE
TOTAL
18 (36%)
32 (64%)
50
14-18
1 (6%)
1(3%)
2 (4%)
19-59
15 (83%)
30 (94%)
45 (90%)
>60
2 (11%)
1 (3%)
3 (6%)
14-18
57
46.8
51.9
19-59
47.07
46.15
46.5
>60
39.45
39
39.3
7 (39%)
10 (31%)
17 (34%)
4 (22%)
12 (38%)
16 (32%)
7(39)
10(21%)
17 (34%)
Number (%)
Age group
BMI (mean)
Obesity Types
Obese (30-40)
Morbidly
obese (40-50)
Super obese
*Dineros, Obesity Surgery, 2007
Weight Reduction in ALL Patients*
Postoperative
Period
Initial Weight
(kg+ SD)
Weight Loss
(kg + SD)
% Excess
Weight Loss
BMI
(kg / m2)
Start
126.7+ 25.4
0
0.00
48.0+ 11.7
1 month
115.9 + 19.4
10.7 + 6.4
8.50%
43.2 + 9.2
3 months
113.2 + 21.4
13.4 + 6.4*
10.60%
42.3 + 9.9
6 months
93.5 + 24.7
33.1+ 10.9*
26.10%
33.7 + 7.1
9 months
91.4 + 20.8
35.3 +10.4*
27.90%
32.4 + 8.7
12 months
68.6+ 10.8
38.3 +11.9*
31.00%
27.5 + 3.1
Dineros, Obesity Surgery,
2007
COMPLICATIONS
• Early Complications
•
•
•
•
•
Wound infection 2/50
Pneumonia 1/50
Dehydration 1/50
Gastritis 1/50
Leakage 1/50
COMPLICATIONS
• Late Complications
• Band Slippage 2/20 (10%)
• Stomal Stenosis 1/20 (5%)
• Ventral Hernia 1/5 (20%)
STARTING WEIGHT:
307 lbs; BMI 49.44
END WEIGHT:
156 lbs; BMI 25.16
STARTING WEIGHT:
516 lbs; BMI 83.10
END WEIGHT:
258 lbs; BMI 37.01
100 kg
(220 lb)
76 kg (168
lb)
BYPASS on Non- obese
• 2 mildly overweight
• Duodenal bypass lowered fasting insulin,
fasting glucose, and HgbA1c within 1 month
after surgery
Diabetes Surgery Summit,
Rome, 2007