What types of hernias are common post-bariatric surgery?

Common Hernias After Bariatric Surgery

Internal hernias are the most common type of hernia after bariatric surgery, particularly after Roux-en-Y gastric bypass (RYGB), occurring in up to 3.3% of patients and representing a significant cause of small bowel obstruction. 1

Types of Post-Bariatric Surgery Hernias

Internal Hernias

• Petersen's hernia - Most common (55.9% of internal hernias), occurs in the space between the Roux limb mesentery and the transverse mesocolon 1, 2
• Jejunojejunostomy (enteroenterostomy) hernia - Second most common (35.3% of internal hernias), occurs at the mesenteric defect created at the jejunojejunal anastomosis 1, 2
• Mesocolic hernia - Occurs when the Roux limb is placed in a retrocolic position through a defect in the transverse mesocolon

Other Hernias

• Incisional hernias - Can occur at trocar sites or previous incisions 1, 3
• Hiatal hernias - Can develop after sleeve gastrectomy (SG) or RYGB, presenting with symptoms of bloating, abdominal pain, regurgitation, and food intolerance 4
• Ventral hernias - May preexist from previous abdominal surgery or develop at trocar sites 3

Risk Factors and Incidence

• The incidence of internal hernias is higher with retrocolic Roux placement (6.0%) compared to antecolic placement (3.3%) 1, 2
• Rapid weight loss increases the risk of internal hernia development due to enlargement of mesenteric defects 1
• Internal hernias can present in a bimodal fashion:
  • Early presentation (within 2-58 days postoperatively) - 22.9% of cases
  • Late presentation (187-1,109 days postoperatively) - 77.1% of cases 2

Clinical Presentation

• Internal hernias typically present with:

  • Acute onset, persistent crampy/colicky abdominal pain, mostly located in the epigastrium 1
  • Nausea and vomiting
  • Abdominal distension
  • The triad of persistent epigastric pain, pregnancy, and history of RYGB should raise high suspicion for internal hernia 1

• Hiatal hernias after bariatric surgery present with:

  • Bloating, nausea, vomiting
  • Abdominal pain
  • Regurgitation
  • Food intolerance or dysphagia 4

Diagnostic Approach

• CT scan is the diagnostic test of choice for internal hernias 5
• Upper GI contrast studies, CT scans, and endoscopy are complementary in diagnosing hiatal hernias (used in 80%, 70%, and 56% of cases respectively) 4
• Laboratory tests including white blood cell count and C-reactive protein help assess for infection/inflammation 5

Management

Internal Hernias

• Early explorative laparoscopy is mandatory in hemodynamically stable patients with suspected internal hernia 1
• Surgical exploration should begin from the alimentary limb at the gastrojejunal anastomosis, following it distally to evaluate Petersen's space and the intermesenteric defect 1
• After reducing the hernia, all mesenteric defects should be closed with non-absorbable sutures 1, 6

Preventative Measures

• Complete closure of all mesenteric defects during the initial bariatric procedure is strongly recommended 2, 6
• Prophylactic Petersen's space herniorrhaphy with non-absorbable polypropylene non-interrupted sutures significantly reduces the incidence of Petersen's hernia (0.02% vs 0.1%) 6

Hiatal Hernias

• Repair of post-bariatric hiatal hernias improves symptoms in >70-80% of patients 4
• Repair techniques include posterior cruroplasty after reducing the neo-stomach into the abdomen or conversion of sleeve gastrectomy to RYGB 4

Pitfalls and Caveats

• Internal hernias can evade radiologic testing and may present with vague symptoms, leading to delayed diagnosis 7
• Prompt clinical recognition and treatment is necessary to prevent small bowel infarction 7
• In patients with significant weight loss, loss of soft tissue support can lead to recurrent episodes of small bowel obstruction requiring emergency repair 3
• Any new onset abdominal symptoms in patients with history of bariatric surgery should raise suspicion for complications including hernias 1

By understanding the types, presentation, and management of post-bariatric surgery hernias, clinicians can improve outcomes and reduce morbidity and mortality in this patient population.