Overview
Definition:
Richter's hernia is a type of abdominal wall hernia where only a portion of the antimesenteric border of the small intestine protrudes through the fascial defect
Strangulation occurs when this incarcerated bowel segment becomes compromised due to vascular compression, leading to ischemia and potential necrosis
Small incision repair refers to minimally invasive surgical techniques, often using local anesthesia and limited dissection, aiming to reduce morbidity and recovery time.
Epidemiology:
Richter's hernia is less common than other types of hernias, accounting for approximately 0.7-1.5% of all incarcerated hernias
It is more frequently seen in femoral hernias (up to 10% of femoral hernias) and Richter's type is observed more often in elderly patients or those with multiple comorbidities
Strangulation is a common complication due to the tight fascial rings of some hernia orifices.
Clinical Significance:
Strangulated Richter's hernia is a surgical emergency due to the risk of bowel gangrene, perforation, peritonitis, and systemic sepsis
Prompt diagnosis and surgical intervention are crucial to prevent life-threatening complications
Understanding the unique presentation and management strategies, including minimally invasive approaches, is vital for surgical residents preparing for DNB and NEET SS examinations.
Clinical Presentation
Symptoms:
Sudden onset of severe, localized abdominal pain
Nausea and vomiting, often projectile
Abdominal distension
Palpable, tender, irreducible lump in the groin or affected hernia site
Absence of bowel obstruction symptoms like obstipation, though partial obstruction can occur
Fever may indicate strangulation or perforation.
Signs:
A tender, irreducible bulge at the hernia site (inguinal, femoral, umbilical, incisional)
Signs of systemic toxicity: tachycardia, hypotension, fever
Skin discoloration over the bulge may indicate impending gangrene
Bowel sounds may be hyperactive or absent depending on the degree of obstruction
Percussion tenderness over the lump.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on the presence of a tender, irreducible hernia bulge and signs of strangulation
Imaging is used to confirm diagnosis and assess bowel viability
Definitive diagnosis is often made intraoperatively
The clinical picture of a focal, tender, irreducible lump without overt signs of complete bowel obstruction is highly suggestive.
Diagnostic Approach
History Taking:
Detailed history of pain onset and character
Previous history of hernias or surgery
Presence of comorbidities like COPD, obesity, or constipation
Any history of trauma to the area
Absence of complete bowel obstruction symptoms can be misleading
Focus on localized pain and the irreducible lump.
Physical Examination:
Careful examination of all common hernia sites (inguinal, femoral, umbilical, incisional)
Palpation for tenderness, reducibility, and size of the bulge
Assess for cough impulse
Examine for signs of strangulation and systemic toxicity
Digital rectal examination may be considered in some cases to rule out other causes of lower abdominal pain.
Investigations:
Complete Blood Count (CBC): Leukocytosis may be present
Serum electrolytes and renal function tests: To assess hydration and electrolyte balance
Imaging: Ultrasound of the abdomen and groin is the initial modality of choice, can identify incarcerated bowel loops, fluid collections, and assess vascularity using Doppler
CT scan of the abdomen and pelvis with intravenous contrast is highly sensitive and specific for confirming strangulation, assessing bowel viability, and identifying the exact location and extent of the incarcerated bowel segment.
Differential Diagnosis:
Femoral hernia, inguinal hernia, incarcerated umbilical hernia, incisional hernia, strangulated bowel obstruction from other causes, appendicular abscess, ectopic testis, lymphadenopathy, psoas abscess, saphena varix.
Management
Initial Management:
NPO status
Intravenous fluid resuscitation
Broad-spectrum intravenous antibiotics (e.g., a third-generation cephalosporin with metronidazole)
Analgesia for pain control
Nasogastric tube insertion if significant vomiting or distension is present.
Surgical Management:
Urgent surgical exploration is indicated in all cases of suspected strangulated Richter's hernia
Small incision repair techniques include open repair under local anesthesia, or laparoscopic repair
Open repair involves a limited incision over the hernia sac to reduce the incarcerated bowel and then performing a standard herniorrhaphy or hernioplasty
Laparoscopic repair allows for a wider view of the abdominal cavity, better assessment of bowel viability, and can be performed with smaller port sites
The key is to assess bowel viability
if viable, it is reduced
if non-viable, resection and anastomosis are necessary.
Bowel Viability Assessment:
Intraoperative assessment of the incarcerated bowel segment
Pink, briskly bleeding serosa, and presence of peristalsis indicate viability
Pallor, dusky discoloration, absent pulsations, and lack of peristalsis suggest non-viability
Fluorescein angiography can be used intraoperatively to assess viability
If resection is needed, it is typically a limited enterectomy followed by primary anastomosis or stoma formation.
Postoperative Care:
Continued IV fluids and antibiotics
Monitor for signs of peritonitis, anastomotic leak, or recurrent hernia
Pain management
Early ambulation
Gradual return to oral intake
Drain management if placed
Monitor for wound complications.
Complications
Early Complications:
Bowel perforation, peritonitis, intra-abdominal abscess, wound infection, anastomotic leak (if resection performed), phlebitis, urinary retention
Recurrent hernia formation.
Late Complications:
Chronic pain at the surgical site, incisional hernia at the repair site, adhesions leading to bowel obstruction, infertility (rare, particularly with inguinal hernia repair in males).
Prevention Strategies:
Early diagnosis and prompt surgical intervention are paramount
Meticulous surgical technique to avoid iatrogenic injury
Appropriate prosthetic mesh use in tension-free repairs
Careful assessment of bowel viability during surgery
Adequate antibiotic prophylaxis.
Prognosis
Factors Affecting Prognosis:
The extent of bowel necrosis and the presence of perforation or peritonitis are the most critical factors
Patient's age, comorbidities, and promptness of surgical intervention also significantly impact outcomes
Successful repair with viable bowel has a good prognosis.
Outcomes:
With prompt surgical management and viable bowel, the prognosis is generally good, with a low recurrence rate for well-performed repairs
Outcomes are significantly poorer in cases with bowel gangrene, perforation, and peritonitis, leading to increased morbidity and mortality.
Follow Up:
Routine follow-up to monitor for wound healing, signs of infection, and early recurrence
Patients who have undergone bowel resection will require specific monitoring for anastomotic integrity and nutritional status
Education on recognizing signs of recurrent hernia is important.
Key Points
Exam Focus:
Richter's hernia involves only a portion of the bowel antimesenteric border
Strangulation is common and a surgical emergency
CT scan is crucial for diagnosis and assessment of viability
Small incision repair aims for minimal morbidity
Bowel viability assessment is critical intraoperatively
Non-viable bowel requires resection and anastomosis.
Clinical Pearls:
Always consider Richter's hernia in a patient with sudden, localized abdominal pain and an irreducible, tender bulge, especially without full bowel obstruction symptoms
Ultrasound can be a quick bedside tool for initial assessment
Be prepared for bowel resection if viability is compromised
Laparoscopic approach offers better visualization of the bowel and abdominal cavity.
Common Mistakes:
Delaying surgical intervention due to the absence of complete bowel obstruction symptoms
Misdiagnosing strangulated Richter's hernia as a simple incarcerated hernia or other benign lump
Inadequate assessment of bowel viability intraoperatively
Performing a repair without addressing strangulated or necrotic bowel
Failing to consider mesh in tension-free repairs where appropriate.