Clinical Guidelines | PCP Toolkit

Surgical Eligibility Criteria

The following guidelines reflect current consensus recommendations from the American Society for Metabolic and Bariatric Surgery (ASMBS), the National Institutes of Health (NIH), and the MBSC clinical advisory panel:

BMI-Based Indications

BMI ≥ 40 kg/m² (Class III obesity) regardless of comorbidity status
BMI 35–39.9 kg/m² with one or more obesity-related comorbidities
BMI 30–34.9 kg/m² with poorly controlled type 2 diabetes or metabolic syndrome (selected cases, per 2022 ASMBS/IFSO guidelines)

Additional Requirements

Documented history of failed non-surgical weight management attempts
Psychological clearance from a qualified behavioral health professional
Nutritional counseling with a registered dietitian
Medical clearance from primary care and relevant specialists
Tobacco cessation for minimum 6–8 weeks prior to surgery
Ability and willingness to adhere to lifelong follow-up and supplementation

Procedure Selection

The choice of bariatric procedure should be individualized based on patient characteristics, comorbidities, and surgical goals. The most commonly performed procedures include:

Sleeve Gastrectomy

The most frequently performed bariatric procedure in the United States. Involves removal of approximately 80% of the stomach along the greater curvature. Restrictive mechanism with hormonal effects. Expected excess weight loss of 50–70% within 12–18 months.

Roux-en-Y Gastric Bypass

Combines restriction with mild malabsorption. Creates a small gastric pouch connected directly to the jejunum, bypassing the duodenum and proximal jejunum. Particularly effective for patients with type 2 diabetes and gastroesophageal reflux disease. Expected excess weight loss of 60–80%.

Biliopancreatic Diversion with Duodenal Switch

A more complex procedure combining sleeve gastrectomy with significant intestinal bypass. Produces the greatest weight loss among standard bariatric procedures but carries higher risk of nutritional deficiencies. Typically reserved for patients with BMI ≥ 50 or severe metabolic disease.

Long-Term Monitoring Standards

Primary care physicians should maintain ongoing surveillance for the following:

Nutritional deficiencies: Annual labs including iron, B12, folate, vitamin D, calcium, zinc, copper, thiamine, and fat-soluble vitamins as indicated by procedure type
Bone health: DEXA scan at 2 years post-surgery, then as clinically indicated; monitor PTH and vitamin D closely
Mental health: Screen regularly for depression, anxiety, disordered eating, body image concerns, and substance use disorders (alcohol use disorder risk increases after bypass)
Weight regain: Address early with behavioral intervention, dietary reassessment, and consideration of pharmacotherapy or revision surgery referral
Dumping syndrome: Educate patients on dietary triggers; manage with meal timing and composition adjustments
Gallstone formation: Consider ursodiol prophylaxis during the rapid weight loss phase (first 6 months)

MBSC Quality Benchmarks

The Michigan Bariatric Surgery Collaborative tracks outcomes across all participating sites to identify best practices and improve care statewide. Key performance indicators include 30-day complication rates, readmission rates, weight loss at 1 year, and resolution of comorbidities. Data from the MBSC registry informs the guidelines presented in this toolkit.

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