Overview
Definition:
Pediatric inguinal hernia refers to the protrusion of abdominal contents through a weakness or defect in the abdominal wall in the inguinal canal
Inguinal herniotomy is the surgical procedure to repair this defect, typically by ligating and dividing the sac within the inguinal canal, and closing the internal ring.
Epidemiology:
Inguinal hernias are common in infants and children, occurring in 1-5% of term infants and up to 30% of premature infants
They are more common in males (5-10:1 ratio) and on the right side
Indirect hernias are the most common type, resulting from the failure of the processus vaginalis to close.
Clinical Significance:
Undiagnosed or unrepaired inguinal hernias pose risks of incarceration and strangulation, leading to bowel obstruction, ischemia, and potentially intestinal necrosis
Early diagnosis and surgical intervention are crucial to prevent these life-threatening complications and ensure optimal outcomes.
Clinical Presentation
Symptoms:
A palpable bulge in the groin or scrotum, which may be more prominent when the child is crying, coughing, or straining
The bulge may disappear when the child is relaxed
Incarceration may present with irritability, vomiting, abdominal distension, and failure to pass stool
Strangulation presents with a tense, tender, irreducible bulge and signs of acute abdomen.
Signs:
A visible or palpable bulge in the inguinal region or scrotum that may be reducible
Palpable hernial sac
In incarcerated hernias, the bulge is tense, tender, and irreducible
Signs of strangulation include erythema of the overlying skin, fever, and signs of peritonitis.
Diagnostic Criteria:
Diagnosis is primarily clinical, based on physical examination findings of a reducible or irreducible bulge in the inguinal canal
In cases of doubt, especially in infants, an ultrasound may be used
Definitive diagnosis is confirmed at surgery.
Diagnostic Approach
History Taking:
Inquire about the presence of a bulge, its timing (e.g., with crying), reducibility, and any associated symptoms like vomiting, fever, or changes in bowel habits
Assess for any signs of incarceration or strangulation, such as irritability and distension.
Physical Examination:
Perform a thorough examination with the child in both supine and erect positions if possible
Carefully palpate the inguinal canal for a bulge, assessing its reducibility and tenderness
A transillumination test can help differentiate a hydrocele from a hernia sac
Examine the scrotum for any masses.
Investigations:
In most cases, no investigations are required beyond clinical assessment
Ultrasound may be considered in ambiguous cases or to rule out other scrotal pathology
Blood tests are generally not indicated unless signs of sepsis or strangulation are present.
Differential Diagnosis:
Undescended testis, hydrocele, spermatocord, lymphadenopathy, femoral hernia, undiagnosed testicular torsion (in males), and ovarian cyst (in females)
Incarcerated hernias can be mistaken for an inflamed lymph node or an undescended testis.
Management
Initial Management:
For an incarcerated, non-strangulated hernia, attempt gentle manual reduction under sedation
If successful, proceed with elective surgery
If reduction fails or if signs of strangulation are present, immediate surgical exploration is warranted.
Surgical Management:
The standard treatment is open inguinal herniotomy
The surgical steps involve incision of the external oblique aponeurosis, dissection of the spermatic cord structures (in males) or round ligament (in females), identification and ligation of the hernial sac at its origin from the internal inguinal ring, and closure of the internal ring and external oblique fascia
Laparoscopic techniques are also used increasingly.
Postoperative Care:
Postoperative care typically involves pain management with analgesics
Patients are usually discharged on the same day or the next day
Advise parents on wound care, activity restrictions (avoiding strenuous activity for 2-4 weeks), and signs of complications to watch for
Wound infection is a common concern.
Age Specific Considerations:
In neonates and premature infants, caution is needed during dissection to avoid injury to delicate structures
Bilateral hernias are more common in neonates, and bilateral repair may be considered
Recurrence rates are slightly higher in younger children.
Complications
Early Complications:
Wound infection, hematoma formation, recurrence of hernia, injury to spermatic cord or vas deferens, injury to testis, nerve injury (leading to chronic pain or paresthesia), urinary retention, and anesthetic complications.
Late Complications:
Chronic pain, infertility (due to damage to vas deferens or testicular blood supply), cosmetic deformity of the scrotum, and recurrence of hernia
Recurrence rates are generally low, around 1-5% after open repair.
Prevention Strategies:
Meticulous surgical technique, appropriate antibiotic prophylaxis (though debated for elective cases), careful handling of tissues, proper identification and high ligation of the hernial sac, and adequate closure of the internal ring are key
Minimizing tension on the repair can also help prevent recurrence.
Prognosis
Factors Affecting Prognosis:
The prognosis is generally excellent for uncomplicated hernias repaired promptly
Factors influencing outcome include the presence of incarceration or strangulation, the skill of the surgeon, and the occurrence of complications
Early repair of even small, asymptomatic hernias is recommended due to the risk of incarceration.
Outcomes:
With appropriate surgical management, the vast majority of children achieve a full recovery with no long-term sequelae
The risk of recurrence is low, and functional outcomes related to fertility are typically preserved when operative techniques are sound.
Follow Up:
Follow-up is usually brief, often around 1-2 weeks postoperatively to check wound healing and assess for any immediate complications
Long-term follow-up is generally not required unless there is a recurrence or suspicion of late complications such as chronic pain or infertility.
Key Points
Exam Focus:
Understand the anatomy of the inguinal canal and processus vaginalis
Differentiate indirect vs
direct hernias (though indirect are far more common in pediatrics)
Recognize the signs of incarceration and strangulation
Know the surgical steps of herniotomy, including high ligation of the sac
Be aware of potential complications and their management.
Clinical Pearls:
Always attempt gentle reduction of incarcerated hernias before proceeding to urgent surgery
Examine the contralateral side, especially in neonates, as bilateral hernias are common
Consider the diagnosis in any infant with unexplained irritability and vomiting
The goal is complete obliteration of the sac and closure of the internal ring.
Common Mistakes:
Failure to identify or ligate the hernial sac at its origin (leading to recurrence)
Injury to the spermatic cord structures (vas deferens, blood vessels) in males
Inadequate closure of the internal inguinal ring
Misdiagnosing an incarcerated hernia as an undescended testis or an inflamed lymph node.