What are the indications and guidelines for sleeve gastrectomy?

Sleeve Gastrectomy: Indications and Guidelines

Primary Indications

Sleeve gastrectomy should be considered for patients with BMI ≥35 kg/m² or BMI 30-34.9 kg/m² with concurrent metabolic disease such as type 2 diabetes, hypertension, or dyslipidemia. 1 Lower BMI thresholds (≥25 kg/m²) apply to Asian populations due to different body composition and metabolic risk profiles. 1

BMI-Based Criteria

• BMI ≥35 kg/m²: Surgery indicated regardless of comorbidities 1
• BMI 30-34.9 kg/m²: Surgery indicated with metabolic disease (type 2 diabetes, hypertension, dyslipidemia, NAFLD/MASLD) 1
• BMI <35 kg/m²: Trial of nonsurgical therapy (lifestyle modification, pharmacotherapy) required before surgical referral 1

Special Population Considerations

In patients with compensated cirrhosis and BMI >35 without clinically significant portal hypertension, sleeve gastrectomy may be considered at centers with dual expertise in liver transplantation and bariatric surgery. 1 For decompensated cirrhosis, bariatric surgery should only occur at the time of or after liver transplantation. 1

Preoperative Requirements

Mandatory Evaluations

• Presurgical nutrition assessment to identify deficiencies and establish baseline nutritional status 1
• Mental health evaluation to assess psychological readiness and identify eating disorders 1
• Additional evaluations determined by surgeon based on comorbidities and surgical risk 1

Contraindications to Screen For

• Hiatal hernia (relative contraindication requiring repair) 1
• Active gastric ulcers (absolute contraindication until healed) 1
• Uncontrolled gastroesophageal reflux disease (relative contraindication; consider alternative procedure) 2, 3
• BMI >60 kg/m² (increased risk of postoperative gastric fistula) 3

Expected Outcomes

Weight Loss

• 12-month weight loss: Approximately 25% total body weight loss 1
• Excess weight loss: 49.4% at 1 year, 61.52% at 2 years, declining to 57.6% at 5 years 4, 2
• Success criteria: >20% total weight loss and >50% excess weight loss maintained for at least 1 year 5

Metabolic Benefits

• Type 2 diabetes: 60% complete remission, 40% improvement at 36 months 5
• Hypertension: 75% remission at 36 months 5
• Dyslipidemia: 52% remission at 36 months 5
• NAFLD/MASLD: 84.6% remission at 36 months 5
• Insulin resistance: 89.4% remission at 36 months 5

Complications and Risk Management

Early Complications (≤30 days)

• Anastomotic/staple line leaks: 1-7% incidence, representing the most serious early complication 1
• Stenosis: 1-9% incidence, managed with endoscopic dilation 1
• Postoperative bleeding: 11% incidence 1
• Venous thromboembolic events: Prophylaxis mandatory 1

Critical pitfall: BMI >60 kg/m² significantly increases gastric fistula risk; consider staged approach or alternative procedure. 3

Late Complications

• Gastroesophageal reflux disease: Develops in 9.8% within first year, decreasing to 7.4% at 5 years 2
• Nutritional deficiencies: Requires lifelong supplementation and monitoring 1

Postoperative Nutritional Management

Mandatory Supplementation

All patients require lifelong micronutrient supplementation including thiamin, vitamin B12, folate, iron, vitamin D, calcium, vitamin A, vitamin E, vitamin K, zinc, and copper. 1 Specific doses vary by procedure but must be monitored regularly.

Protein Requirements

• Daily protein intake: 60-80 g/day or 1.0-1.5 g/kg ideal body weight to preserve lean body mass 6

Hydration Protocol

• Fluid intake: 1.5-2 liters daily, consumed separately from meals 6
• Technique: Sip fluids throughout the day rather than large volumes at once 6

Follow-Up Protocol

Close follow-up every 4-6 weeks initially enables support for lifestyle changes and early detection of complications. 1 Long-term follow-up determined by bariatric team should continue indefinitely to monitor weight maintenance, nutritional status, and comorbidity resolution. 1, 6

Monitoring Parameters

• Weight and BMI at each visit 6
• Nutritional deficiencies via laboratory testing 6
• Symptoms of stenosis: Persistent fullness, vomiting, or solid food intolerance 6
• Comorbidity status: Diabetes control, blood pressure, lipid panels 5

Sleeve Gastrectomy vs. Other Procedures

Sleeve gastrectomy is preferred over Roux-en-Y gastric bypass in patients with cirrhosis or those requiring future biliary access because it maintains endoscopic access to the biliary tree and avoids malabsorption. 1 Expected weight loss is slightly less than RYGB (25% vs. 30% at 12 months) but with lower rates of internal hernia and marginal ulceration. 1