Principles of bariatric surgery

Unit viDr anand (pg)

Under gudience of

Prof. m.ramesh

Asst.prof.k.shivarama krishanaAsst.prof.c.ramchandraiah

BARIATRIC SURGERY (SURGERY FOR MORBID OBESITY) (Bariatric =Baros: heaviness, and

pressure.)

INTRODUCTION Bariatric surgery is currently only modality

that provides a significant sustained loss of weight for the patient with morbid obesity.& with related co-morbidities

Goals The goal of bariatric surgery is to improve health in

morbidly obese patients by achieving long-term, durable weight loss.

It involves reducing caloric intake and/or absorption of calories from food, and may modify eating behavior by promoting slow ingestion of small boluses of food.

Restrictive operations restrict the amount of food intake by reducing the quantity of food that can be consumed at one time, which results in a reduction in caloric intake.

Malabsorptive procedures limit the absorption of nutrients and calories from ingested food by bypassing the duodenum and predetermined lengths of small intestine.

BARIATRIC EVALUATION

In 1969, Mason and Ito performed the first gastric bypass, in which a loop of jejunum was connected to a transverse proximal gastric pouch.

Bile reflux esophagitis was severe postoperatively, In 1977 Griffin to developed the Roux-en-Y

modification of the gastric bypass In 1980, Mason described vertical banded

gastroplasty (VBG), a restrictive procedure in which stapling was used to create a proximal gastric pouch of the upper lesser curvature of the stomach,

with placement of a restrictive band to form its outlet to the rest of the stomach

In Italy, late 1970, Scopinaro had developed and popularized the biliopancreatic diversion (BPD) procedure along with its modification to include a duodenal switch (DS), has been the only major malabsorptive operation to enjoy long-term success.

The laparoscopic approach to bariatric surgery became available in the 1990

In 1994 Belachew and colleagues performed the first laparoscopic adjustable gastric banding (LAGB) operation .

Wittgrove and Clark performed the first laparoscopic Roux-en-Y gastric bypass (LRYGB) the same year.

In 2001 LAGB was approved for use in the United States by the U.S. Food and Drug Administration.

OBESITY

EPIDEMIOLOGY Obesity now considered as a "Killer lifestyle" disease

is an important cause of preventable death worldwide.

According to the World Health Organization (WHO), 1.2 billion people worldwide are officially classified as overweight.

This is probably the most sedentary generation of people in the history of the world.

In the Indian scenario, even with the growing awareness about health and fitness, more than 3 percent (3 crores ) of the Indian population is obese

ETIOLOGYAn excess of caloric intake in relation to

caloric expenditure results in deposition of fat or adipose tissue

Obesity is multifactorial Genetic Environmental factors Diet Culture Other factors

DIET

Genetics plays an important role in the development of obesity.

Although the children of parents of normal weight have a 10% chance of becoming obese,

The children of two obese parents have an 80 to 90% chance of developing obesity by adulthood.

The weight of adopted children correlates strongly with the weight of their birth parents. Furthermore, concordance rates for obesity in monozygotic twins are double those in dizygotic twins.2

Differential Diagnosis and Related Diagnoses

A few endocrine diseases are associated with obesity, including hypothyroidism,

Cushing's disease, and adult-onset diabetes mellitus.

However, patients who seek medical or surgical treatment for morbid obesity rarely have an endocrine etiology of their obesity.

syndrome X.( combination of central obesity, glucose intolerance, dyslipidemia, and hypertension)

CLASSIFICATION The degrees of obesity are defined by

body mass index, BMI (calculated as weight in kilograms

divided by height in meters squared).

Classification BMI Range (kg/m2)

Normal weight 20–25 Overweight 26–29 Obese 30–34 Severely obese 35–49 Superobese ≥50

COMORBIDITIES, Degenerative joint disease Low back pain, hypertension, Obstructive sleep apnea, GERD) Cholelithiasis, Type 2 diabetes, hyperlipidemia, Hypercholesterolemia, asthma,

hypoventilation syndrome of obesity, 5

Fatal cardiac arrhythmias, right-sided heart failure,

Migraine headaches deep vein thrombosis, Fungal skin rashes, skin abscesses, Stress urinary incontinence, infertility,

dysmenorrhea, Depression, Abdominal wall hernias, Increased incidence cancers such as

those of the uterus, breast, colon, and prostate.

Life expectancy Obesity has a profound effect on overall health

and life expectancy largely secondary to weight-related

comorbidities. It is estimated that a man who is severely

obese at age 21 will live 12 years less than a nonobese individual,

and a severely obese woman will live 9 years less.

This is largely due to the fact that severely obese men often are dead of comorbid medical conditions, especially cardiac arrhythmias and coronary artery disease, by age 50

Treatment and mangement

Non surgical Surgical

NON SURGICALLIFE STYLE MODIFICATIONS DIET a deficit of 500 kcal per day, resulting in

a weekly deficit of 3500 kcal, translates to the loss of one pound of fat a week.

EXCERISE Behavior modification Pharamacotherapy

Life style modifications

PHARAMCOTHERAPY Pharmacotherapy is a second tier therapy

usually used in heavier patients (BMI >27)

when lifestyle changes alone have failed.

It is employed alone or in combination with lifestyle changes

Sibutramine & orlistat are c (FDA)–approved drugs for weight loss treatment.

Orlistat is a potent and selective inhibitor of gastric and pancreatic lipases that reduces lipid intestinal absorption,

sibutramine is a noradrenaline and 5-hydroxytryptamine reuptake inhibitor that works as an appetite suppressant.

Despite their different MOA they effectively produce weight loss of 6 to 10% of initial body weight at 1 year,

SURGICAL MANGEMENT

INDICATIONS CONTRA-INDICATIONS

PRE-OPERATIVE EVALUATION TYPES OF SURGICAL PROCEDURES POST SURGICAL MANGEMENT FOLLOW UP &OUTCOME

Indications Patients that have a BMI of 35 kg/m 2 or

more with comorbidity, or those with a BMI of 40 kg/m 2 or greater

regardless of comorbidity, Candidates must have attempted weight

loss in the past by medically supervised diet regimens, exercise, or medications.

patients aged 18 to 60 years. Adolescent patients with morbid obesity

may be considered for bariatric surgery under select circumstances.

CONTRA-INDICATIONS: Patients who are unable to undergo

generalAnesthesia because of cardiac, pulmonary, or hepatic disease,

Patients with ongoing substance abuse, unstable psychiatric illness,

inadequate ability to understand the consequences of surgery are also considered to be poor surgical candidates.

those who are unwilling or unable to comply with apostoperative lifestyle changes, diet, supplementation, or follow-up may not undergo these procedures.

PRE OPERATIVES EVALUTIONS INCLUDES Patient selection Pre operative prepartion anesthesiology assessment

Pateint selection Multidisciplinary team evaluation Physician Specific nutritional counseling and

education is required based on the operation to be performed

Psychologic assessment Treatment of the depression is felt to

improve postoperative outcomes.

Preoperative Preparation comorbidities and other medical

problems Screening for coronary artery disease in

patients >50 years of age sleep apnea in severely obese patients,

when all routinely undergo sleep studies GERD taking medication, a preoperative

screening upper endoscopy to rule out Barrett's esophagus and intrinsic lesions of the stomach or duodenum is recommended

patients who are taking anticoagulants for prosthetic cardiac valves or

recent venous thromboembolism, anticoagulation therapy must be managed

H/O venous thromboembolism or who are felt to have multiple risk factors for postoperative venous thromboembolism are potential candidates for preoperative placement of a temporary inferior vena cava filter.

Such filters are placed the day before surgery & removed 3 to 6 weeks postoperatively

Ultrasound of the abdomen in patients planning to undergo LRYGB who have an intact gallbladder to rule out the presence of gallstones.

Evaluation of thyroid function is recommended preoperatively, because hypothyroidism is not uncommon in this patient population.

Serum chemical analysis, liver function tests, and the usual screening blood tests are performed.

Blood tests to determine baseline nutritional parameters commonly reveal abnormally low iron and vitamin D levels

Anesthesiology Issues Cardiopulmonary evaluation to identify

any underlying pathology that requires preoperative treatment to decrease perioperative morbidity from cardiopulmonary complications

Two major difficulties the anesthesiologist faces when administering a general anesthetic to a severely obese patient are vascular access and airway management

Alterations in the metabolism of specific anesthetic drugs in the severely obese include a larger volume of distribution

Restrictive    Laparoscopic adjustable gastric banding

(LAGB)    Sleeve gastrectomy (SG)   Vertical banded gastroplasty (VBG)a

  Malabsorptive    Biliopancreatic diversion (BPD) Jejunoileal bypass (JIB)

  Combined restrictive and malabsorptive    Roux-en-Y gastric bypass (RYGB)   BPD with duodenal switch (DS)

Indications for Conversion from Laparoscopic to Open Surgery

1. Failure to establish an adequate pneumoperitoneum 2. Hemodynamic adverse reaction to pneumoperitoneum 3. Intra-abdominal adhesions precluding safe access or

presenting excessive difficulty in accessing abdomen 4. Hepatomegaly such that retraction is not feasible or

organ visualization is obscured even with retraction 5. Intraoperative complications such as hemorrhage that

are best managed with an open approach 6. Exceedingly thick body wall precluding adequate trocar

access or manipulation 7. Existing large upper abdominal wall hernia that

optimally can be repaired at the same time using the same incision

LAPARASCOPIC Adjustable Gastric banding:

Silicon band with adjustable diameter placed at the entry of stomach (cardia)

Two types of bands have been used The original Lap-Band Adjustable Gastric

Banding System, ( Allergan) most frequently.

The Swedish adjustible gastric band, Realize Adjustable Gastric Band by Ethicon

Adjustable gastric banding

• Sep/1993= first laparoscopic AGB (Belachew M)

• Types of Adjustable Bands:

1-Bioenterics = Lap-Band=Silicone

2-Swedish adjustable gastric band

Mechanism of Action Adjustable gastric banding involves the

minimally invasive (laparoscopic) or open-approach

placement of a silicone band around the proximal stomach to restrict the amount of solid food that can be ingested at one time.

the adjustable nature of the band allows the amount of restriction to be increased or decreased, depending upon the patient's weight loss

Technique

The patient is placed in the steep reverse Trendelenburg position. Six laparoscopic ports are placed. A 5-mm liver retractor is used to elevate the left hepatic lobe.

A 15-mL gastric calibration balloon is used to identify the locationbegins with division of the peritoneum at the angle of His, then division of the gastrohepatic ligament in its avascular area (the pars flaccida) to expose the base of the right crus of the diaphragm

Once the band is passed around the proximal stomach, it is locked into its ring configuration through its own self-locking mechanism.

Once the band is securely locked in place, the buckle portion of the band is located on the lesser curvature of the stomach

Patient Selection and Preparation

Most LAGB procedures are done on an outpatient basis.

the relative risk of the procedure is lower than that of most other bariatric operations,

which makes this procedure more suitable to offer to older, more medically ill, or higher-risk patient populations.

Poor candidates for LAGB patients who have had previous upper gastric

surgery, such as a Nissen fundoplication, due to the potential tissue compromise in taking down the wrap to place the band.

Pateint who , are immobile, are unable to exercise, nibblers on high-calorie sweets, and expect to be able to continue their dietary habits

Postoperative Care Patients are given clear liquids a few hours after the

procedure. A Gastrografin swallow is obtained on the first

postoperative day to confirm band position and patency.

Patients can generally be discharged 1 to 2 days after surgery with a liquid diet for 4 weeks.

At that time, a gradual transition to a regular diet is started.

Band adjustment may be performed with fluoroscopic guidance initially at 10 to 12 weeks.

Patients are assessed monthly for weight loss and tolerance of oral intake.

Band adjustments are made accordingly every 4 to 6 weeks during the first year following laparoscopic adjustable gastric banding.

Advantages Laparoscopic adjustable gastric banding is a

relatively simple procedure that takes less operative time than the more complex procedures such as laparoscopic RYGB or laparoscopic biliopancreatic diversion.

The mortality rate is low (0.06%), as are conversion rates (0 to 4%).

No staple lines or anastomoses are required. Recovery is rapid and hospital stay is short.

The adjustable nature of the laparoscopic band allows the degree of restriction to be optimized for the patient's weight loss.

Increasing band diameter may relieve postoperative vomiting

Disadvantages With this procedure, there is a potential for port

site complications and the need for frequent postoperative visits for band adjustment.

Some patients (5 to 10%) experience band slipping or gastric prolapse, which usually requires reoperation.

Other potential problems include band erosion, port-related complications, gastroesophageal reflux, alterations in esophageal motility, and esophageal dilatation.

Should inadequate weight loss occur, revision to Roux-en-Y gastric bypass is feasible, but may be technically difficult because of adhesions in the area surrounding the band

EARLY COMPLICATIONS OF ADJUSTABLE GASTRIC BANDING..

Wound infection pneumonia Injury of stomach or oesophagus Bleeding

Late complications Food intolerance or noncompliance Band slippage(stomach prolapse) Pouch dilation Band erosion into stomach Port complications Re operation rate Oesophageal dilatation Failure to lose weight Leakage of ballon or tubing

Open Roux-en-Y Gastric Bypass Mechanism of Action RYGB is both a gastric restrictive procedure

and a mildly malabsorptive procedure. A small gastric pouch restricts food intake,

while the Roux-en-Y configuration provides malabsorption of calories and nutrients.

Mason described the optimal parameters for restriction necessary for adequate weight loss, including a gastrojejunostomy of 1.2 cm or less in diameter and a gastric pouch of 15 to 30 mL.

The abdomen is entered through a midline incision and is thoroughly explored. The gallbladder is inspected and palpated for gallstones

Three superimposed staple lines are applied to the stomach so as to create a proximal pouch of 15 to 30 mL

The ligament of Treitz is identified and a point 15 to 45 cm distally is identified.

The jejunum is divided with a linear stapling device.

The mesentery is divided between clamps and a side-to-side jejunojejunostomy is created with a linear stapler to create a 45- to 75-cm Roux limb for a standard gastric bypass,

a 150-cm limb for a long-limb modification in the superobese. With a lengthened Roux limb, there is a greater degree of malabsorption for improvement of weight loss.

The Roux limb is brought through the transverse mesocolon.

A 1-cm gastrojejunal anastomosis is created between the gastric pouch and the jejunum, using a circular stapler or a hand-sewn, two-layer technique.

The hand-sewn anastomosis is created over a 30F dilator

Postoperative Care If a nasogastric tube is left in place at the

time of surgery, it is removed within 24 hours.

Gastrografin swallow is generally obtained on the second or third postoperative day and liquids are started thereafter.

Patients are generally discharged 2 to 6 days after surgery.

Advantages TheRYGB is more effective than vertical

banded gastroplasty in terms of weight loss.

In a more recent study in which sweet-eaters were assigned to gastric bypass and non–sweet-eaters were assigned to vertical banded gastroplasty,

RYGB has been demonstrated not only to prevent the progression of non–insulin-dependent diabetes mellitus, but also to reduce the mortality from diabetes mellitus, primarily due to a reduction in deaths from cardiovascular disease.

Durable control of diabetes mellitus is achieved following gastric bypass, along with or resolution of other comorbidities such as hypertension, sleep apnea, and cardiopulmonary failure.

Disadvantages Dumping syndrome including distal gastric distention and

internal hernia.

Laparoscopic Roux-En-Y Gastric Bypass (LRGB) The laparoscopic approach to gastric bypass

(LRYGB) was first described in 1994 The major feature of the operation is the creation

of a proximal gastric pouch of small size (often <20 mL) that is totally separated from the stomach

A Roux limb of proximal jejunum is brought up and anastomosed to the pouch.

The pathway of that limb can be anterior to the colon and stomach, posterior to both, or posterior to the colon and anterior to the stomach.

The length of the biliopancreatic limb from the ligament of Treitz to the distal enteroenterostomy is from 20 to 50 cm, and the length of the Roux limb is 75 to 150 cm.

Gastric bypass

• First Laparoscopic gastric bypass was in 1993 by Wittgrove, Clark, and Tremblay.

Patient Selection and Preparation

LRYGB is an appropriate operation to consider for most patients eligible for bariatric surgery.

Relative contraindications to LRYGB include previous gastric surgery, previous antireflux surgery, severe iron deficiency anemia,

Distal gastric or duodenal lesions that require ongoing future surveillance, and Barrett's esophagus with severe dysplasia

Preoperative flexible upper endoscopy for all patients contemplating RYGB is advocated by some to rule out lesions of the stomach or duodenum

Postoperative Care and Follow-Up Patients undergoing LRYGB usually are

hospitalized for 2 to 3 days We routinely perform a postoperative oral

contrast study on the 1st POD to rule out a leak

an early asymptomatic leak or to edema or stenosis of the enteroenterostomy or to any other obstructive pattern of the proximal bowel

follow-up visits are usually for 3 mthen onths, 6 months, and 1 year after surgery, annually after that.

testing for postoperative nutritional deficiencies.

Outcomes Patients undergoing LRYGB usually lose

between 60 and 80% of excess body weight during the first year after surgery

Postoperative nutritional complications after LRYGB include :

iron deficiency anemia in 20%, vitamin B12 deficiency in 15%, and vitamin D deficiency in at least 15%,

which usually is present preoperatively.

EARLY COMPLICATIONS of Roux-en –y gastric bypass

Anastomic leak (1-3%) Pulmonary embolism,DVT Wound infection(mc open apprroach) GI hemorrhage,bleeding Respiratory insuffciency,pneumonia Acute distension of distal stomach

LATE COMPLICATIONS Stomal stenosis mc Bowel obstruction Internal hernia Cholelithiasis Micro nutrient deficiencies Marginal ulcer Staple line distruption Ventral hernia(MC open approach)

Life long oral or IM vit B-12 supplememtation

Iron,folate,calcium specific nutrient deficency

Biliopancreatic Diversion and Duodenal Switch

Biliopancreatic diversion (BPD) was first described by,Scopinaro and colleagues in ItalY,

It involves resection of the distal half to two thirds of the stomach and creation of an alimentary tract of the most distal 200 cm of ileum, which is anastomosed to the stomach

The biliopancreatic limb is anastomosed to the alimentary tract either 75 or 100 cm proximal to the ileocecal valve, depending on the protein content of the patient's diet

Mechanism of Action

A 50- to 100-cm common absorptive alimentary channel is created proximal to the ileocecal valve; digestion and absorption are limited to this segment of bowel.

Indications

This procedure is primarily indicated for the superobese or for those who have failed restrictive bariatric procedures.

Less commonly, some surgeons perform BPD as a primary operation in the non-superobese.

Contraindications

Patients with anemia, hypocalcemia, and osteoporosis, and

those who are not motivated to comply with stringent postoperative supplementation regimens may not be appropriate for this procedure.

AdvantaGES the malabsorptive component of the BPD

allows for excellent results in terms of weight loss.

This operation may be more effective than gastric bypass or restrictive surgery in patients with severe morbid obesity (e.g., BMI greater than 70 kg/m 2 ),

Disadvantages The BPD is technically a more complex

procedure than the restrictive procedures. Protein malnutrition with anemia, hypoalbuminemia, edema, and alopecia are among the serious adverse sequelae of this operation.

Severe vitamin deficiencies may occur, leading to osteoporosis and night-blindness.

Treatment requires prolonged hyperalimentation and supplementation

COMPLICATIONS biliopancreatic diversion with duodenal switch

Fat malabsorption leads to diarrhea foul smelling gas

Nutrional deficiencies Malabsorption of fat soluble vitamins

(ADE&K) Iron deficiency Protein-energy malnutrition

Sleeve Gastrectomy

First introduced by Ganger Micheal in 2002

It is the first step when you do Biliopancreatic diversion with Duodenal switch procedure (BPD+DS)

It is temporary step to reduce weight before the permanent procedure which is BPD+DS (when BPD+DS is difficult to be done duo to excessive fat or huge Lt. liver lobe)

Patient Selection and Preparation Patients undergoing SG two groups. One group is high-risk superobese

patients considering eventually undergoing the second procedure to complete the DS operation.

The other group is patients who have a BMI of <50 kg/m2 and have decided that they prefer the SG operation.

TECHNIQUE The surgeon begins the gastric resection

by dividing the vessels along the greater curvature of the stomach using the Harmonic scalpel.

Division is begun 2 to 3 cm proximal to the pylorus and continued to the angle of His

Outcome

SG results in excellent short-term weight loss

Depending on body size, weight loss is in the range of 45–50% of excess weight for patients with a BMI of >60 kg/m2,

For patients with a BMI of 35 to 50 kg/m2 with a 32F pouch size, excess weight loss at 3 years was recently reported as being 60%

Vertical Gastrectomy Advantages Stomach volume is reduced, but it tends to function

normally so most food items can be consumed in small amounts.

Eliminates the portion of the stomach that produces the hormones that stimulates hunger (Ghrelin).

No dumping syndrome because the pylorus is preserved.

Minimizes the chance of an ulcer occurring. By avoiding the intestinal bypass, the chance of

intestinal obstruction (blockage), anemia, osteoporosis, protein deficiency and vitamin deficiency are almost eliminated.

Very effective as a first stage procedure for high BMI patients (BMI >55 kg/m2).

Limited results appear promising as a single stage procedure for low BMI patients (BMI 35-45 kg/m2).

Appealing option for people with existing anemia, Crohn’s disease and numerous other conditions that make them too high risk for bypass

Complication of SG

As with any surgery, there can be complications. Complications can include:

DVT (blood clot in leg) Pulmonary Embolus (blood clot to lung) Pneumonia Splenectomy Gastric leak and fistula. Postoperative bleeding Small bowel obstruction Death

Vertical Banded Gastroplasty

Indications for VBG

Big…big size single meal eater

Non-sweet eater Non-compliance patients

motivated patients

Does not loss significant by dieting history

Advantages 60% a mean excess weight loss Less than 10% early morbidity rate Less than 1% perioperative mortality

disadvantages Nearly 80% failure rate (long term follow-

up Poor weight loss maintenance 15% to 20% reoperation rate duo to

stomal outlet stenosis or severe reflux

Special Issues Relating to the Bariatric Patient

Bariatric Procedures in the Female Patient: Pregnancy and Gynecologic Issues

Hormonal levels in female patients are related to body weight.

Obesity alters the levels of estrogen and progesterone available for normal ovulation, which results in abnormal ovulation patterns, amenorrhea, and difficulty conceiving.

the increased chances of gestational diabetes and hypertension make the pregnancy high risk. Macrosomia is increased.

RYGB had a lower incidence of diabetes, macrosomia, and cesarean section than those who had not had surgery.

Bariatric Surgery in Morbidly Obese Adolescents

Bariatric surgery in morbidly obese adolescents is controversial.

Surgery may be indicated in this population because of the dismal failure of the conservative methods of weight control,

adolescent obesity, and the many disabling and deadly obesity-related comorbidities of adulthood.

Bariatric surgery should be seriously considered after conservative methods have failed.

IN ELDERLY Most clinical trials exclude older patients, and

little is known about the benefits of diets or drugs that induce weight loss in these age groups.

Mechanical complications of obesity, such as osteoarthritis and static respiratory complications, seem to improve with weight loss, even at higher ages.

Recent studies suggest that bariatric surgery, previously considered contraindicated in obese patients above age 60, can be safely performed even in patients above age 70, with the same benefits as those seen in younger patients.

Type 2 Diabetes surgeons performing RYGB that patients

who had undergone the operation showed improvement or near resolution of type 2 diabetes well before they had achieved maximum weight loss.

Metabolic Syndrome

Metabolic syndrome is characterized by central obesity, glucose intolerance, dyslipidemia, and hypertension.

Metabolic syndrome is a common finding in patients with severe obesity, occurring in 52% of individuals in one report.

All the associated metabolic problems of metabolic syndrome respond to surgical therapy to produce weight loss.

Diabetes and pre-diabetes (fasting plasma glucose of 100–124 mg/dL) are effectively treated by both RYGB and LAGB

Resolution of Other Comorbid Medical Problems with Bariatric surgery:

Obstructive sleep apneaMusculoskeletal problems, degenerative joint disease and low back pain,

Post operative follow up: High protein,low-fat diet,supplement

multivitamins,iron,and calcium. Ursodil minimize the risks of

development gallstones Nutritional and metabolic blood tests

needPerformed on frequent basis.3 months,6months,12 months after surgery,then

annually

Post bariatric surgery body contouring

Massive weight loss associated with flabby skin,abdominal skin overhang and pendulous breast

Redundant roll of tissue associate with hygiene problems

TREATMENT Conventional surgery lipoplasty Combination of 2 procedures Abdominoplasty , buttock lift, lower body

lift Thigh lift ,upper arm lift. Facelift, breast

reduction.mastopexy.COMPLICATIONS Hematomas. seromas, skin slough ,fat necrosis & DVT

Thank you