Epidemiology & Risk Factors

  • Prior abdominal surgery (especially midline laparotomy incisions).
  • Surgical site infection (SSI) is the single strongest modifiable risk factor.
  • Patient factors: Obesity, DM2, advanced age, smoking, malnutrition (hypoalbuminemia), and corticosteroid use (impaired wound healing).
  • Increased intra-abdominal pressure: Chronic cough (COPD), chronic constipation, ascites, or pregnancy.
  • Surgical factors: Emergency surgery, poor suture technique, or tension on the fascial closure.

Clinical Features

  • History: Pt reports a painless or aching bulge at or near a prior surgical scar. Bulge typically enlarges with coughing, standing, or Valsalva maneuvers and decompresses/flattens when supine.
  • Physical Exam: Palpable fascial defect along the surgical scar.
  • Reducibility:
    • Reducible: Contents easily pushed back into the peritoneal cavity.
    • Incarcerated: Hernia contents are trapped; painful, firm, and non-reducible mass.
    • Strangulated: Compromised blood supply. Characterized by severe pain, fever, tachycardia, overlying skin erythema/warmth, and signs of SBO (nausea, vomiting, obstipation).

Diagnosis

  • Initial Test: Physical examination with pt in both supine and standing positions during a Valsalva maneuver (highly sensitive for most palpable defects).
  • Confirmatory/Best Imaging: CT abdomen/pelvis with contrast.
    • Used to confirm diagnosis when PE is equivocal (e.g., in obese pts).
    • Identifies occult incarceration, measures defect size, and assists in pre-op planning.
  • Alternative Imaging: Abdominal US can be used in pregnant pts or children to avoid radiation.

Differential Diagnostics

  • Diastasis Recti: Differentiated by a widening of the linea alba without a true fascial defect or risk of strangulation; occurs mainly when rising from supine.
  • Abdominal Wall Hematoma/Seroma: Typically occurs in the immediate post-op period; exquisitely tender (hematoma), fluctuant (seroma), with no fascial defect on imaging.
  • Surgical Site Infection / Abscess: Differentiated by localized erythema, warmth, purulent drainage, and fever; lacks a reducible mass.

Management

  1. Strangulated or Acute Incarcerated Hernia with SBO:
    • First-line: Emergency surgical exploration (laparoscopy or laparotomy).
    • Steps: Reduce hernia contents, assess bowel viability, resect necrotic bowel, and repair the fascial defect. Avoid synthetic mesh in contaminated fields (high risk of mesh infection).
  2. Symptomatic but Reducible Hernia:
    • First-line: Elective surgical repair.
    • Technique: Mesh repair (open or laparoscopic) is preferred over primary suture repair for defects >2 cm due to significantly lower recurrence rates.
  3. Asymptomatic or Mildly Symptomatic Hernia:
    • First-line: Watchful waiting may be considered in asymptomatic pts with high-risk surgical comorbidities. Provide counseling on signs of incarceration/strangulation.

Complications

  • Small bowel obstruction (SBO) secondary to herniated bowel loops.
  • Incarceration and Strangulation leading to bowel necrosis, perforation, and peritonitis/sepsis.
  • Hernia recurrence (most common long-term complication; up to 10-20% even with mesh repair).
  • Enterocutaneous fistula (occurs if mesh erodes into underlying bowel loops).