34 Introduction to Bariatric Surgery

Question 1

Criteria for Weight Loss Surgery

• considered when/
• only offered to individuals who/

Answer 1

• considered only when all other options have been exhausted.
• only offered to individuals who are medically considered to be morbidly obese, such as those who:
  
  • Have a body mass index (BMI) greater or equal to 35, with one or more significant obesity-related conditions including:
    
    • High blood pressure
    • Diabetes
    • Arthritis
    • Sleep apnea
    • High cholesterol
  • Have a BMI greater than 40, regardless of other medical conditions
  • Are 14 to 75 years of age (site specific, with some exceptions)
  • Have a history of multiple failed attempts with diet plans, behavioral changes, and medical therapy
  • Have realistic expectations and motivations
  • Are capable of understanding the procedure and implication
  • Understand and accept the operative risks
  • Are committed to following the diet, vitamin supplementation, exercise program, and follow-up necessary for health and weight maintenance

Question 2

Deciding whether to undergo bariatric surgery

• The decision to undergo bariatric surgery
• Commitment to Lifestyle Change
• Other Medical Conditions

Answer 2

• The decision to undergo bariatric surgery
  
  • complex and intensely personal, with many factors to take into account.
  • For individuals who are not morbidly obese, the risk of surgery far outweighs the expected health benefits of the weight loss.
  • Bariatric surgery is not performed for cosmetic reasons.
• Commitment to Lifestyle Change
  
  • Bariatric or weight loss surgery is only effective when used in combination with diet and exercise.
  • You must be willing to comply fully with all recommended lifestyle changes (attitude, healthy eating, and physical activity).
• Other Medical Conditions
  
  • Diseases associated with morbid obesity often lead to significant and permanent damage to one or more organ systems.
  • Sleep apnea commonly affects Lungs
  • Congestive failure or coronary artery disease commonly affects Heart
  • Diabetes and high blood pressure commonly affects Kidneys
  • Stress and arthritis commonly affects Bones and joints

Question 3

Deciding whether to undergo bariatric surgery

• Age
• Mortality

Answer 3

• Age
  
  • surgery candidates are between the ages of 14 and 75
  • higher level of attention for those who are at the high and low ends of the age spectrum.
  • Each patient is evaluated as to his or her ability to tolerate surgery, both physically and emotionally.
  • Selected younger patients may be considered candidates for a surgical approach to weight loss, depending on their history, medical problems, understanding of the procedure, family support, and other factors.
• Mortality
  
  • The overall 30-day mortality for bariatric surgical procedures is less than 1 percent.
  • Increased mortality is associated with older age (65 years and >) and male gender.
  • Chronic disease and super-obesity (BMI >50) contribute to an increased risk of death with bariatric surgical procedures.
  • The super-obese patients are at increased risk for wound infections, dehiscence, venous thromboembolism and are likely to have multiple severe obesity related medical comorbidities.

Question 4

Types of bariatric surgery:
Roux-en-Y gastric bypass (p.13-15)

Answer 4

• involves the creation of a small gastric pouch and an anastomosis to a Roux limb of jejunum that bypasses 75 to 150 cm of small bowel, thereby restricting food and limiting absorption.
• the most common weight-loss procedure performed.

Question 5

Types of bariatric surgery:
Laparoscopic adjustable gastric band (LAGB) (p.9-10)

Answer 5

• a purely restrictive procedure that involves placement of an adjustable silicone band at near the gastroesophageal junction, limiting the amount of food consumed.
• Restriction can be adjusted by injecting saline into an access port connected to the band.
• the second most common weight-loss surgery performed in the United States.
• has the lowest mortality rate among all bariatric procedures.

Question 6

Types of bariatric surgery:
Laparoscopic sleeve gastrectomy (LSG) (p.11-12)

Answer 6

• a restrictive procedure initially developed as part of a staged approach for high-risk super-obese patients.
• Sleeve gastrectomy involves creating a “sleeve” of stomach and removes a large portion of the greater curvature of the stomach leaving a small tube along the lesser curvature.
• produces a decrease in ghrelin levels for up to a year, which may reduce the desire for food.

Question 7

Complications

Answer 7

• Bleeding–Significant bleeding after gastric bypass has been described in 0.6 to 4.0 percent of patients. A higher rate of postoperative gastrointestinal bleeding was observed following laparoscopic versus open GBP in a prospective randomized study. Early bleeding typically occurs from one of the surgical anastomotic and/or staple lines.
• Wound infection– significantly more frequent with open (10 to 15 percent) than laparoscopic (3 to 4 percent) gastric bypass procedures.
• Leaks– The rate of anastomotic leak in RYBG is 1.5 to 6 percent and can be as high as 35 percent in revisional surgery. If not diagnosed in a timely fashion, the mortality rate can be as high as 15 percent.
• Pulmonary embolism and deep venous thrombosis–Pulmonary embolism (PE) remains the most common cause of mortality in the perioperative period after weight-loss surgery and occurs in 0.2-1% of patients. It can account for more than 50 percent of deaths. The most common risk factors associated with fatal PE include severe venous stasis disease, BMI >60, truncal obesity, and obesity-hypoventilation syndrome
• Cardiovascular complications–Cardiovascular complications, including myocardial infarction and cardiac failure, are a common cause of mortality in the perioperative period. An analysis of 13,871 morbidly obese patients from a national registry reported that the mortality from cardiovascular events ranged from 12.5 to 17.6 percent.
• Pulmonary complications–Respiratory failure accounts for 11.3 percent of perioperative mortality after weight-loss surgery
• Postoperative hypoglycemia

Question 8

Specific later complications:
Roux-en-Y gastric bypass (RYGB):
Dumping syndrome

• Dumping syndrome
  
  • can occur when/
  • may contribute to/
• Early dumping syndrome
• Late dumping syndrome

Answer 8

• Dumping syndrome
  
  • can occur when high levels of simple carbohydrates are ingested.
  • may contribute to weight loss in part by causing the patient to modify his/her eating habits.
• Early dumping syndrome
  
  • has a rapid onset, usually within 15 minutes.
  • the result of rapid emptying of food into the small bowel.
  • Due to the hyperosmolality of the food, rapid fluid shifts from the plasma into the bowel occur, resulting in hypotension and a sympathetic nervous system response.
  • Patients often present with colicky abdominal pain, diarrhea, nausea, and tachycardia.
  • Patients should avoid foods that are high in simple sugars.
  • Behavioral modification, such as small, frequent meals, and separating solids from liquid intake by 30 minutes, are also advocated.
  • Usually, early dumping is self-limiting and resolves within 7 to 12 weeks.
• Late dumping syndrome
  
  • a result of the hyperglycemia and the subsequent insulin response leading to hypoglycemia that occurs 2 to 3 hours after a meal.
  • Patients present with dizziness, fatigue, diaphoresis and weakness.
  • The treatment is similar to early dumping syndrome.

Question 9

Specific later complications:
Roux-en-Y gastric bypass (RYGB):
Additional complications

Answer 9

• Metabolic and nutritional derangements/ Vitamin and mineral deficiencies
• Stomal stenosis
• Marginal ulcers
• Cholelithiasis
• Ventra/l incisional hernia (open surgery)
• Internal hernias
• Postoperative hypoglycemia
• Change in bowel habits
• Failure to lose weight and weight regain

Question 10

Specific complications

• Specific complications of laparoscopic adjustable gastric banding:
• Specific complications of laparoscopic sleeve gastrectomy

Answer 10

• Specific complications of laparoscopic adjustable gastric banding:
  
  • Stomal stenosis
  • Port infection
  • Band erosion
  • Band slippage and gastric prolapse
  • Port malfunction
  • Esophagitis
  • Esophageal dilatation
• Specific complications of laparoscopic sleeve gastrectomy:
  
  • bleeding, narrowing or stenosis of the stoma, and leaks.

Question 11

Post-surgical Management

Answer 11

• Bariatric surgery has been shown to improve anthropometric measures (weight, BMI, waist circumference) and to improve blood pressure, diabetes, cholesterol and other health parameters.

Question 12

Nutritional Management

• Following bariatric surgery, patients experience/
• Early diet
• The immediate postoperative diet recommendations emphasize/
• Nutritional deficiencies that occur after bariatric surgery depend significantly on the type of surgery performed.
  
  • Restrictive procedures
  • Malabsorptive procedures
• Nutritional labs

Answer 12

• Following bariatric surgery, patients experience significant improvements in medical comorbidities and changes in hunger and/or satiety related to alterations in food pathway.
• Early diet
  
  • based on a staged approach with emphasis on texture and nutrient needs.
  • A large variation in food tolerances is seen, and patients who have undergone RYGB or LAGB benefit from well-planned dietary advancement, both to ensure proper healing of the surgery and to develop life-long healthy eating habits .
• The immediate postoperative diet recommendations emphasize hydration and protein intake.
  
  • To avoid food impaction, patients are started on a liquid diet immediately following surgery.
• Nutritional deficiencies that occur after bariatric surgery depend significantly on the type of surgery performed.
  
  • Restrictive procedures such as gastric banding are the least likely to cause nutritional deficits, since none of the intestine is bypassed.
  • Malabsorptive procedures such as biliopancreatic diversion or mixed restrictive/malabsorptive procedures (e.g., Roux-en-Y gastric bypass) can result in serious nutritional problems when patients do not take required supplements after surgery.
    
    • Vitamins and minerals that are commonly deficient in this circumstance include vitamin B12, calcium, vitamin D, thiamine, folic acid, iron, zinc, and magnesium.
    • Rare ocular complications have been reported with hypovitaminosis A.
• Nutritional labs should be drawn at 6, 12 months then yearly indefinitely.

Question 13

Laparoscopic vs. Open Surgery (p.16)

Answer 13

• Smaller scars
• Less pain
• Quicker recovery
• Fewer hernias / infections
• Same weight loss