Surgical management of morbid obesity in adults

(Bariatric surgery)

M K ALAMALMAAREFA COLLEGE

ILOs

At the end of this presentation students will be able to:

Define obesity and its different forms Understand epidemiology, and risk factors, Describe pathogenesis and natural history of

obesity. Clinical presentation and differential diagnosis Describe medical and surgical management

Introduction

• Obesity- a major health problem worldwide

• Overweight individuals in the world: 1.7 billion

• Epidemic proportion in the Western society.

• Major risk factor for many diseases.

• Significant morbidity and mortality.

Swedish study:

Bariatric surgery was associated with a

reduced number of cardiovascular

deaths and a lower incidence of

cardiovascular events in obese adults.[1]

Bariatric Surgery

Bariatric surgery is an effective therapy for morbid obesity.

3 basic concepts for bariatric surgery:

(1) Gastric restriction- adjustable gastric banding, sleeve gastrectomy

(2) Gastric restriction with mild malabsorption- Roux-en-Y gastric bypass

(3) A combination- mild gastric restriction and malabsorption (duodenal switch).

The 2 most common bariatric procedures:

1.Laparoscopic Adjustable gastric banding

2.Laparoscopic Roux-en-Y gastric bypass.

Measure of obesity

• BMI (Body mass index) = Patient's mass (wt.) in kg ÷ height in meters squared.

• Normal BMI- 18.5-24.9 kg/m2.

• Overweight- BMI of 25-29.9 kg/m2

• Obese- BMI of 30 kg/m2

• Morbid obesity - BMI of 35 kg/m 2 or greater -with severe obesity-related

comorbidity, or BMI of 40 kg/m 2 or greater without comorbidity

• Waist circumference : >88 cm (35 in) in women or >102 cm (40 in) in men

strongly correlates with an increased risk of obesity-related disease.

Aetiology

• Complex, multifactorial chronic disease

• Interaction of several factors: Genetic, endocrine,

metabolic, environmental (social and cultural),

behavioral, and psychological.

• Basic mechanism: Energy intake exceeds energy output.

Pathophysiology

• Obesity- result of an imbalance in energy expenditure and caloric intake.

• Leptin is a hormone made primarily in adipocytes

• Leptin negative feedback signal on the hypothalamus → alter the

expression of several neuroendocrine peptides that regulate

energy intake and expenditure.

• Central resistance to leptin is a prominent feature of obesity.

• Increased leptin levels in obese strongly correlate with the BMI.

• Leptin treatment works well in patients who are leptin deficient

but in obese who have high levels has shown limited efficacy.

Presentation

• Morbid obesity: Harbinger of many other diseases.

• Cardiovascular: Hypertension, atherosclerotic heart and

peripheral vascular disease- MI, CVA, peripheral venous

insufficiency, thrombophlebitis, pulmonary embolism.

• Respiratory: Asthma, obstructive sleep apnea.

• Metabolic: Type 2 diabetes, hyperlipidemia.

• Musculoskeletal: Back strain; disc disease; osteoarthritis

of the hips, knees, ankles, and feet

Presentation• Gastrointestinal: Cholelithiasis, GORD, fatty liver disease, hepatic

cirrhosis, hepatic carcinoma, colorectal carcinoma.

• Urologic: Stress incontinence.

• Endocrine and reproductive: Polycystic ovary syndrome, increased

risk of fetal abnormalities, male hypogonadism.

• Carcinoma: Breast, ovary, endometrium, prostate, and pancreas.

• Dermatologic: Intertriginous dermatitis.

• Neurologic: Carpal tunnel syndrome.

• Psychologic: Depression, eating disorders, body image disturbance

Indications for surgery

• Surgery: A treatment of last resort. Dieting, exercise, psychotherapy, and drug treatments have failed.

• National Institutes of Health (NIH): Consensus Conference Panel criteria for surgical treatment:

• BMI > 40 kg/m2

• BMI > 35 kg/m2 with high-risk comorbid diseases (Sleep apnea, Pickwickian syndrome, diabetes, or degenerative joint disease)

Contraindications to Bariatric surgery

• Illnesses that greatly reduce life expectancy (advanced cancer and end-stage renal, hepatic, & cardiopulmonary disease.

• Illness unlikely to be improved with weight reduction,

• Patients unable to understand the nature of bariatric

surgery or the behavioral changes required afterward (untreated schizophrenia, active substance abuse).

• Noncompliance with previous medical care

PREOPERATIVE EVALUATION

• Cardiac, pulmonary, psychiatric, & endocrine evaluations.

• Exclude patients who may not benefit from surgery.

• Optimize potential good candidates for surgery.

• Preoperative nutritional consultation: Detailed diet history

& explaining preoperative and postoperative diet protocol

PREOPERATIVE EVALUATIONLaboratory Studies:• CBC • Biochemical profile • Liver function tests • Thyroid function tests • Lipid profile • Coagulation tests • Serum iron & total iron binding capacity (TIBC) • Vitamin B-12, folic acid, • Blood typing • Urinalysis.

PREOPERATIVE EVALUATION

Imaging Studies:

• Chest radiography

• Ultrasonography of the gallbladder

PREOPERATIVE EVALUATION

Diagnostic Procedures:

• Upper GI endoscopy to rule out intrinsic upper gastrointestinal disease.

After gastric bypass surgery, the ability to visualize the distal stomach and the duodenum is difficult.

Treatment & managementMedical Therapy:

• A preoperative trial of weight loss is beneficial to

ensure patient compliance with the postoperative

diet protocol.

• A preoperative liquid diet can shrink the liver,

thus facilitating the surgical procedure.

Surgical Therapy

Surgical Technique

• Open surgery technique

• Laparoscopic technique.

• The laparoscopic approach has currently

become the more popular approach.

Surgical Therapy Gastric bypass

• Restrictive and a malabsorptive component.

• Restrictive element: Creation of a small gastric pouch

(approximately 20 mL in volume) and a small outlet that,

on distention by food, causes the sensation of satiety.

• Malabsorptive element: Result of bypassing the distal

stomach, the entire duodenum, and varying the length

of the jejunum.

• Separation of food from the biliopancreatic secretions.

Surgical Therapy

Gastric bypass

Surgical Therapy Gastric bypass

• Weight loss usually exceeds 100 lb /about 65-70% of excess

body weight/ 35% of BMI.

• Weight loss generally levels off in 1-2 years.

• Regain of 20 lb to a long-term plateau is common.

• Dumping syndrome: rapid passage of gastric pouch contents

directly into the small bowel upon ingestion of sweets. The

rapid release of insulin by the pancreas cause symptomatic

hypoglycemia.

Surgical Therapy

Laparoscopic adjustable gastric banding

• A restrictive procedure

• Inflatable band placed around the proximal stomach. Creates a

small gastric pouch (approx. 15 mL) and a small stoma.

• Band is adjustable by adding/removing saline from the band by a

reservoir system accessible through a port. The port is placed

subcutaneously in the anterior abdominal wall.

• Adjustments, performed up to 6 times annually

Surgical Therapy

Laparoscopic adjustable gastric banding

Surgical Therapy

Laparoscopic adjustable gastric banding

• Chew food thoroughly to allow food to pass

• Adjusting the inflation changes the size of the opening through

which food passes but does not change the size of the gastric

pouch

• Deflation of the cuff is useful when the outlet is obstructed.

• Weight loss: 50-60% of excess body wt. in about 2 yrs.

• Can be completely reversed

Surgical Therapy

Biliopancreatic diversion with duodenal switch

Includes the following (see the image below) :

• Lateral 75% gastrectomy, resulting in a tubular stomach

• Duodenum divided past the pyloric valve

• Ileum divided

• Distal end of ileum anastomosed to proximal duodenum

• Common channel created distally with Y-anastomosis

• Optional appendectomy and cholecystectomy

Surgical Therapy

Biliopancreatic diversion with duodenal switch

Surgical Therapy

Biliopancreatic diversion with duodenal switch

• Malabsorption is achieved by separating food from

biliopancreatic digestive fluids

• Fat and protein malabsorption.

• Best weight loss with the least regain

• 75-85% of excess body weight loss is at 18 months

• Pyloric preservation protects against marginal ulceration and

dumping syndrome

• The procedure is technically challenging and difficult

• Still considered investigational.

Surgical Therapy

Laparoscopic sleeve gastrectomy

• The stomach- reduced to about 15-20% of its size.

• The mechanism of weight loss: Gastric restriction

and neurohumoral changes (due to the gastric resection).

Surgical Therapy

Laparoscopic sleeve gastrectomy

Surgical Therapy

Laparoscopic sleeve gastrectomy• Follow-up: 6 months to 3 years- loss of 33-

83% of their excess weight.• Results: LSG has morbidity and effectiveness

between laparoscopic adjustable gastric banding and standard Roux bypass.[25]

• Postoperative complications: Bleeding from the staple line, Intraabdominal collectionsLeak.

Complications of Bariatric surgeryEarly:• Anastomotic leak (1-3%)

• PE, DVT (< 1%)

• Wound infection

• GI hemorrhage (0.5-2%)

• Respiratory insufficiency, pneumonia

• Acute distention of the distal stomach

Late:• Stomal stenosis(20%)

• Small bowel obstruction (1%)

• Internal hernia

• Cholelithiasis

• Micronutrient deficiencies

• Marginal ulcer

• Staple line disruption

Complications of the adjustable gastric band

• Injury of the stomach or esophagus• Food intolerance (most common)• Band slippage (stomach prolapse) (2.2-8%)• Pouch dilatation• Band erosion into the stomach• Reoperation rate (2-41%)• Esophageal dilatation• Failure to lose weight• Port infection, band infection• Leakage of the balloon or tubing

Postoperative care

• Patients on a high-protein, low-fat diet. • Supplement diet with multivitamins, iron, and calcium

on a twice-daily basis.• Ursodiol to minimize the risk of developing gallstones

during the period of acute weight loss. • Modify eating habits- avoid chewy meats and other

foods that may inhibit normal emptying stomach pouch.• Nutritional and metabolic blood tests on a frequent

basis- at 6 months & 12 months after surgery, and then annually thereafter.

Nutritional deficiencies

• Malabsorption of fat soluble vitamins A, D, E, & K

• Vitamin A deficiency- night blindness

• Vitamin D deficiency- osteoporosis

• Iron deficiency

• Protein-energy malnutrition

Post-bariatric surgery body contouring

• Consequences of massive weight loss- flabby skin, abdominal skin overhang, and pendulous breasts.

• Skin does not contract back to its pre-surgery tightness.

• Redundant rolls of tissue- associated with intertrigo and hygiene problems.

• Surgical correction of deformities significantly enhance physical and physiological changes.

• Usual time lapse between gastric bypass and plastic surgery procedures is 12-18 months.

Post-bariatric surgery body contouring

Body contouring procedures

• Abdominoplasty, buttock lift, lower body lift, thigh lift,

upper arm lift, facelift, breast reduction, mastopexy, and/or

augmentation.

• Multiple procedures are usually required, and a

• Staged approach improve safety and outcomes.

• Complications of procedures: hematomas, seromas, fat

necrosis, skin slough, infection, and deep vein thrombosis.

Outcome and Prognosis

• Lifetime care: Nutritional & psychological issues

• Exercise, and lifestyle changes

• Socioeconomic advancement require patient guidance.

• Reduced cardiovascular deaths, heart attack and stroke.

• Significant decrease in low back pain

• Diabetes remission

Thank you!