Gastroenterology · Abdominal Wall Hernias
The facts most likely to be tested
An incarcerated hernia is a non-reducible hernia that remains trapped outside the abdominal cavity, posing a high risk for strangulation.
Strangulated hernia is a surgical emergency characterized by ischemia of the herniated contents due to compromised blood supply, leading to necrosis.
Clinical presentation of a strangulated hernia includes a tender, erythematous, and non-reducible mass associated with fever, tachycardia, and leukocytosis.
Patients with an incarcerated hernia presenting with nausea, vomiting, and obstipation must be evaluated for small bowel obstruction.
Physical examination is the primary diagnostic tool, and forced reduction of a suspected strangulated hernia is strictly contraindicated due to the risk of perforation.
Urgent surgical consultation for emergent herniorrhaphy is the definitive management for any hernia showing signs of strangulation or ischemia.
Computed tomography (CT) of the abdomen and pelvis with intravenous contrast is the imaging modality of choice to confirm the diagnosis and assess for bowel ischemia.
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A 68-year-old male presents to the emergency department with a 12-hour history of severe, constant right groin pain and nausea. He has a known history of a right-sided inguinal hernia that was previously reducible. On physical examination, the patient is febrile (101.2°F) and tachycardic. There is a firm, exquisitely tender, erythematous, and non-reducible mass in the right inguinal canal. Bowel sounds are high-pitched and hyperactive.
What is the most appropriate next step in management?
Emergent surgical consultation for herniorrhaphy
The patient's presentation of a non-reducible, tender, and erythematous mass with systemic signs (fever, tachycardia) is classic for a strangulated hernia, which requires immediate surgical intervention to prevent bowel necrosis.
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Etiology / Epidemiology
Common in elderly and patients with increased intra-abdominal pressure (COPD, obesity, chronic constipation).
Clinical Manifestations
Painful, non-reducible mass; strangulation presents with fever, tachycardia, and overlying skin changes.
Diagnosis
Clinical diagnosis; CT abdomen/pelvis with IV contrast is the gold standard for diagnostic uncertainty.
Treatment
Emergent surgical consultation; do not attempt manual reduction if signs of ischemia are present.
Prognosis
High risk of bowel necrosis and sepsis if surgical intervention is delayed beyond 6 hours.
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Epidemiology & Etiology
Incarceration occurs when a hernia sac becomes trapped outside the abdominal cavity. Primary risk factors include chronic cough, heavy lifting, and prior abdominal surgery. It is most frequently seen in inguinal and femoral hernia types.
Pertinent Anatomy
The femoral canal is the most common site for incarceration due to its narrow, rigid borders. Inguinal hernias pass through the internal inguinal ring, which can act as a constricting neck for protruding bowel loops.
Pathophysiology
Incarceration begins with mechanical obstruction of the bowel lumen. Venous congestion follows, leading to edema and increased intraluminal pressure. If untreated, this progresses to strangulation, where arterial supply is compromised, resulting in ischemia, gangrene, and perforation.
Clinical Manifestations
Patients present with a painful, firm, non-reducible mass. Red flags include fever, leukocytosis, tachycardia, and erythema over the hernia site, which suggest strangulation. Sudden relief of pain followed by diffuse abdominal tenderness may indicate perforation.
Diagnosis
Diagnosis is primarily clinical. If the diagnosis is unclear or complications are suspected, CT abdomen/pelvis with IV contrast is the gold standard to evaluate for bowel wall thickening or lack of enhancement. Avoid barium studies if perforation is suspected.
Treatment
Immediate surgical consultation is required. If the patient is stable and lacks signs of ischemia, a gentle attempt at manual reduction may be performed. Do not attempt reduction if the hernia has been incarcerated for >6 hours or if there is overlying skin erythema.
Prognosis
Delayed treatment leads to bowel necrosis and sepsis. Post-operative monitoring for re-perfusion injury and abdominal compartment syndrome is critical in cases of prolonged ischemia.
Differential Diagnosis
Hydrocele: transilluminates on physical exam
Lymphadenopathy: usually multiple nodes, often associated with infection
Testicular torsion: sudden onset, absent cremasteric reflex
Epididymitis: positive Prehn sign
Lipoma: soft, mobile, non-tender subcutaneous mass