What is the diagnosis and treatment for an inguinal hernia?

Inguinal Hernia: Diagnosis and Treatment

Diagnosis

Inguinal hernias are diagnosed primarily by physical examination, palpating for a bulge or impulse in the groin while the patient coughs or strains. 1

• The classic presentation includes groin swelling accompanied by pain, burning, gurgling, or a dragging sensation that worsens with prolonged activity and improves when lying down 1
• The abdominal bulge typically disappears when the patient is prone 1
• Imaging is rarely necessary for diagnosis, but ultrasonography can be useful when physical examination is equivocal, particularly in athletes without a palpable bulge, or when differentiating from other causes of groin swelling 2, 1

Emergency Assessment

For patients presenting acutely, determine if the hernia is:

• Reducible (can be pushed back into the abdomen)
• Incarcerated (trapped but not compromised)
• Strangulated (blood supply compromised - requires emergency surgery) 3

Systemic inflammatory response syndrome (SIRS), elevated lactate, serum creatinine phosphokinase (CPK), D-dimer levels, and contrast-enhanced CT findings predict bowel strangulation. 4, 5

Treatment Algorithm

Non-Emergency Inguinal Hernias

Mesh repair is the definitive standard treatment for inguinal hernias, with significantly lower recurrence rates compared to tissue repair (0% vs 19%). 3, 6

Surgical Approach Selection:

For bilateral hernias or hernias in women: Laparoscopic repair (TAPP or TEP) is preferred 3, 6

• Advantages include reduced postoperative pain, lower analgesic requirements, faster return to activities, and ability to identify occult contralateral hernias (present in 11.2-50% of cases) 3, 5
• Both TAPP and TEP demonstrate comparable outcomes with low complication rates 3

For unilateral hernias in men: Either open (Lichtenstein) or laparoscopic repair is appropriate 3, 6

• Laparoscopic approach results in less chronic pain development compared to open surgery 6, 3
• Open Lichtenstein repair remains excellent when laparoscopic expertise is unavailable or patient has significant comorbidities 5
• Open repair can be performed under local anesthesia if preferred 5

All inguinal hernias in women should be surgically repaired due to higher risk of femoral hernia component and complications. 6

Emergency/Complicated Inguinal Hernias

Early surgical intervention (<6 hours from symptom onset) is strongly recommended for incarcerated or strangulated hernias, as it significantly reduces the need for bowel resection (OR 0.1) and mortality. 7

Delayed diagnosis beyond 24 hours is associated with significantly higher mortality rates. 4, 5

Mesh Use in Emergency Settings:

Clean surgical field (CDC Class I - incarcerated without strangulation):

• Prosthetic repair with synthetic mesh is strongly recommended (Grade 1A) 3, 8

Clean-contaminated field (CDC Class II - strangulation with bowel resection but no gross spillage):

• Emergent prosthetic repair with synthetic mesh can be safely performed and is associated with significantly lower recurrence risk (OR 0.34) without increased infection rates 8, 3, 7
• Multiple studies demonstrate that mesh repair with concomitant bowel resection shows no significant difference in wound or mesh infection rates compared to hernias with viable contents 8

Contaminated-dirty field (CDC Class III-IV - bowel necrosis with gross spillage or peritonitis):

• For small defects (<3 cm): Primary tissue repair is recommended 8, 3
• For larger defects when direct suture not feasible: Biological mesh may be used, with choice between cross-linked and non-cross-linked depending on defect size and contamination degree 8, 3

Laparoscopic vs Open in Emergency Settings:

Laparoscopic approach (TAPP/TEP) is appropriate for incarcerated hernias without suspected strangulation or bowel compromise 3, 7

• Associated with significantly lower wound infection rates (p<0.018) and shorter hospital stays compared to open repair 3, 7
• No increase in recurrence rates (p<0.815) compared to open approach 3

Open preperitoneal approach is preferable when:

• Strangulation is suspected or bowel resection may be needed 3
• Patient cannot tolerate general anesthesia 3
• Bowel gangrene is present 3

Hernioscopy (laparoscopy through hernia sac) is specifically recommended to assess bowel viability after spontaneous reduction of strangulated hernias, avoiding unnecessary laparotomy and decreasing hospital stay 3, 4, 5

Antibiotic Prophylaxis

• 48-hour antimicrobial prophylaxis for intestinal strangulation and/or concurrent bowel resection (CDC classes II-III) 3, 5
• Full antimicrobial therapy for peritonitis (CDC class IV) 3, 5

Critical Pitfalls to Avoid

The most dangerous pitfall is delaying repair of strangulated hernias, which leads to bowel necrosis, increased morbidity, and significantly higher mortality. 4, 5

• Spontaneous reduction of a previously incarcerated hernia does NOT exclude bowel ischemia - the bowel may have been compromised during incarceration and reduced back while still ischemic, requiring urgent diagnostic laparoscopy 4
• The transition from intermittent, reducible pain to constant pain with abdominal tenderness indicates progression from incarceration to strangulation 4
• Clinical suspicion of strangulation warrants urgent surgery; imaging should not delay surgical exploration 4

During laparoscopic repair (TAPP), always inspect the contralateral side after obtaining patient consent, as occult contralateral hernias are present in 11.2-50% of cases. 3, 5

In emergency settings with suspected strangulation, local anesthesia can be used for incarcerated inguinal hernias only in the absence of bowel gangrene. 3, 5

Postoperative Monitoring

Monitor for:

• Wound infection 3, 5
• Chronic pain 3
• Recurrence 3, 5
• Testicular complications including atrophy and vas deferens injury 5