Management of Strangulated vs. Incarcerated Hernia
Strangulated hernias require immediate surgical intervention, while incarcerated hernias without signs of strangulation can be initially managed with attempted manual reduction followed by urgent surgery if reduction fails. 1
Definitions and Differentiation
- Incarcerated hernia: Hernia contents cannot be reduced back into the abdominal cavity but blood supply remains intact
- Strangulated hernia: Blood supply to hernia contents is compromised, leading to ischemia and potential necrosis
Key Clinical Distinctions
| Feature | Incarcerated Hernia | Strangulated Hernia |
|---|---|---|
| Pain | Moderate, constant | Severe, progressive |
| Tenderness | Present | Marked with peritoneal signs |
| Erythema | Minimal/absent | Present |
| Systemic signs | Usually absent | SIRS (fever, tachycardia, leukocytosis) |
| Urgency | Urgent | Emergent |
Management Algorithm
1. Initial Assessment
- Evaluate for signs of strangulation:
- Severe pain and tenderness
- Erythema over the hernia
- Systemic inflammatory response syndrome (SIRS)
- Peritoneal signs
- Leukocytosis
2. Management of Incarcerated Hernia
Without signs of strangulation:
- Attempt gentle manual reduction in Trendelenburg position
- If successful: Schedule early elective repair (within days)
- If unsuccessful: Proceed to urgent surgical repair (within 24 hours)
Duration of conservative management:
- Safe to attempt non-operative management for up to 72 hours if no signs of strangulation 2
- Monitor closely for development of strangulation signs
3. Management of Strangulated Hernia
- Immediate surgical intervention without delay 2, 1
- Preoperative preparation:
- IV fluid resuscitation
- Broad-spectrum antibiotics
- NPO status
- Type and cross-match blood if significant bowel compromise suspected
4. Surgical Approach
Early intervention (<6 hours from symptom onset) is associated with lower incidence of bowel resection 3
Surgical options:
a) Laparoscopic approach (if patient is hemodynamically stable):
- Benefits: Shorter hospital stay, lower recurrence rates, allows evaluation of hernia contents 3, 4
- Technique: TAPP approach for groin hernias, IPOM+ for ventral hernias 4
b) Open approach (preferred for hemodynamically unstable patients):
- Midline incision over the hernia
- Identification and isolation of hernia sac
- Fascial closure with non-absorbable sutures when possible 1
5. Mesh Considerations
- Mesh repair is preferred over primary tissue repair even in emergency settings 3, 5
- Safe to use mesh in incarcerated/strangulated hernias without contaminated hernia content 5
- For contaminated fields (bowel perforation), consider:
- Biologic or biosynthetic mesh
- Primary repair without mesh if significant contamination
6. Bowel Evaluation and Management
- Assess bowel viability after reduction:
- Viable: Normal color, peristalsis, pulsation in mesentery
- Questionable: Warm with saline, observe for 5-10 minutes
- Non-viable: Resect and anastomose if patient stable
- Bowel resection required in approximately 13.7% of cases 5
Important Considerations and Pitfalls
- Delayed diagnosis significantly increases mortality - time from onset to surgery is the most important prognostic factor 2
- Mortality rates are higher in patients whose treatment is delayed for more than 24 hours 2
- Risk factors for bowel resection include:
- Lack of health insurance
- Obvious peritonitis
- Femoral hernia location 2
- Common pitfall: Relying solely on clinical signs to differentiate strangulation - early signs may be subtle and difficult to detect 2
- Occult hernias may be present (60% in one study) - consider laparoscopic exploration to identify and repair simultaneously 6
By following this algorithm, clinicians can effectively differentiate between incarcerated and strangulated hernias and provide appropriate management to minimize morbidity and mortality.