2.1 Inguinal Hernia

Inguinal hernias are the most common type of hernia in children, accounting for approximately 80% of all pediatric hernias. They occur when abdominal contents protrude through the inguinal canal.

Pathophysiology:

In males, inguinal hernias typically result from failure of the processus vaginalis to close completely. During fetal development, the testes descend from the abdominal cavity through the inguinal canal and into the scrotum. The processus vaginalis, a pouch of peritoneum, precedes the testis and normally obliterates after testicular descent. When it remains patent, it forms a potential space for abdominal contents to herniate.

In females, inguinal hernias are associated with the round ligament of the uterus and the canal of Nuck (the female equivalent of the processus vaginalis).

Figure 1: Anatomy of pediatric inguinal hernia showing the patent processus vaginalis

Classification:

• Indirect inguinal hernia: Most common (99% of pediatric inguinal hernias). Occurs when abdominal contents protrude through the internal inguinal ring and into the inguinal canal through a patent processus vaginalis.
• Direct inguinal hernia: Extremely rare in children. Occurs when abdominal contents protrude through a weakness in the posterior wall of the inguinal canal (Hesselbach’s triangle).

Risk Factors:

• Prematurity (increased risk by 7-10 times)
• Low birth weight
• Male gender
• Family history of inguinal hernia
• Conditions with increased intra-abdominal pressure:
  • Chronic cough
  • Constipation
  • Ascites
  • Ventriculoperitoneal shunt
• Connective tissue disorders (Ehlers-Danlos syndrome, Marfan syndrome)
• Cryptorchidism (undescended testicle)
• Cystic fibrosis

Clinical Presentation:

• Painless, reducible bulge in the groin that may extend into the scrotum or labia
• Bulge often appears during crying, coughing, or straining
• May disappear when the child is relaxed or lying down
• Occasionally painful if incarcerated or strangulated
• May cause irritability in infants

2.2 Umbilical Hernia

Umbilical hernias are the second most common type of hernia in children. They occur when abdominal contents protrude through a weakness in the abdominal wall at the umbilicus (belly button).

Pathophysiology:

During fetal development, the umbilical cord passes through an opening in the abdominal wall called the umbilical ring. This opening normally closes shortly after birth. When closure is incomplete, a weakness remains, allowing abdominal contents (usually intestine and omentum) to protrude through the defect.

Figure 2: Umbilical hernia showing protrusion at the umbilicus (belly button)

Risk Factors:

• Prematurity
• Low birth weight
• African American ethnicity (up to 5x higher incidence)
• Trisomy 21 (Down syndrome)
• Hypothyroidism
• Ehlers-Danlos syndrome
• Beckwith-Wiedemann syndrome

Clinical Presentation:

• Painless, soft, reducible bulge at the umbilicus
• More prominent during crying, coughing, or straining
• Size varies from a few millimeters to several centimeters
• Usually asymptomatic
• Rarely becomes incarcerated or strangulated

Natural History:

Unlike inguinal hernias, most umbilical hernias (90%) close spontaneously by age 4-5 years. The likelihood of spontaneous closure depends on:

• Size of the fascial defect (smaller defects more likely to close)
• Age at presentation (earlier presentation more likely to resolve)

2.3 Epigastric Hernia

Epigastric hernias occur through the linea alba (midline) above the umbilicus and below the xiphoid process. They are the third most common type of hernia in children.

Pathophysiology:

Epigastric hernias result from a weakness or defect in the linea alba, which is the fibrous structure that runs down the midline of the abdomen. These defects allow preperitoneal fat or, rarely, abdominal contents to protrude through.

Figure 3: Epigastric hernia location in the midline above the umbilicus

Clinical Characteristics:

• Usually small (0.5-1 cm)
• Often asymptomatic, discovered incidentally
• May cause discomfort or pain, especially after eating or physical activity
• Typically contains preperitoneal fat rather than intestine
• Multiple defects may be present in 20-30% of cases
• Unlike umbilical hernias, epigastric hernias rarely close spontaneously

2.4 Femoral Hernia

Femoral hernias are rare in children, accounting for less than 0.5% of all pediatric hernias. They occur when abdominal contents protrude through the femoral canal, below the inguinal ligament.

Pathophysiology:

The femoral canal is a potential space located medial to the femoral vein, below the inguinal ligament. A hernia occurs when abdominal contents protrude through this space due to congenital or acquired weakness.

Clinical Characteristics:

• More common in girls than boys (unlike inguinal hernias)
• Often misdiagnosed as inguinal hernia
• Presents as a bulge below the inguinal ligament and lateral to the pubic tubercle
• Higher risk of incarceration due to narrow neck of hernia sac
• Often associated with connective tissue disorders

2.5 Diaphragmatic Hernia

Congenital diaphragmatic hernia (CDH) is a serious birth defect where there is an abnormal opening in the diaphragm, allowing abdominal organs to move into the chest cavity during fetal development.

Pathophysiology:

CDH results from incomplete formation of the diaphragm during embryonic development (weeks 4-10 of gestation). The most common type is a posterolateral defect (Bochdalek hernia), accounting for 90% of cases.

Figure 4: Congenital diaphragmatic hernia showing abdominal organs in the chest cavity

Types:

• Bochdalek hernia: Posterolateral defect (90% of cases), more common on left side (80-85%)
• Morgagni hernia: Anterior defect (2% of cases), typically right-sided
• Central/septum transversum defect: Rare

Clinical Presentation:

• Often diagnosed prenatally through ultrasound
• Severe respiratory distress at birth (tachypnea, cyanosis, grunting)
• Scaphoid (concave) abdomen
• Barrel-shaped chest
• Breath sounds diminished or absent on affected side
• Heart sounds shifted away from affected side
• Difficulty feeding

Associated Complications:

• Pulmonary hypoplasia: Underdevelopment of lungs due to compression by herniated organs
• Pulmonary hypertension: Due to abnormal pulmonary vasculature development
• Cardiac anomalies: Present in 10-20% of cases
• Other congenital anomalies: Neural tube defects, chromosomal abnormalities, etc.

Inguinal, Umbilical, Epigastric, and Femoral Hernias:

• Ultrasound: May be helpful when physical exam is equivocal, especially in:
  • Obese children
  • Children with undescended testes
  • Differentiating hernia from hydrocele or lymphadenopathy
  • Evaluating for incarceration or strangulation
• Abdominal X-ray: Generally not useful for diagnosis of external hernias, but may be indicated if bowel obstruction is suspected in case of incarceration.

Diaphragmatic Hernia:

• Prenatal ultrasound: Often identifies CDH between 16-24 weeks gestation
• Prenatal MRI: May be used to better define the defect and assess lung volume
• Chest X-ray: Shows intestinal loops in thoracic cavity, mediastinal shift
• CT scan: Rarely needed but may provide detailed anatomy before repair
• Echocardiogram: To assess cardiac function and rule out associated cardiac anomalies

Umbilical Hernia:

• Observation is the standard approach for most umbilical hernias in children
• 90% close spontaneously by age 4-5 years
• Factors that predict spontaneous closure:
  • Small defect size (<1.5 cm)
  • Early age at presentation
• Regular follow-up to monitor for changes in size or symptoms

Inguinal, Epigastric, and Femoral Hernias:

• Generally not managed conservatively due to risk of incarceration
• Surgery is the definitive treatment
• Sometimes brief observation may be considered in:
  • Very premature infants until they reach appropriate weight
  • Children with serious medical conditions precluding surgery

Initial Management:

1. Place child in supine position with slight Trendelenburg (feet elevated)
2. Apply ice pack to reduce swelling (10-15 minutes)
3. Provide appropriate pain management
4. Avoid repeated forceful attempts at reduction
5. Gentle, sustained pressure for manual reduction
6. If not reducible within 1-2 attempts, contact surgeon

Sedation-Assisted Reduction:

• May be performed in the emergency department under sedation
• Common sedatives used:
  • Midazolam
  • Ketamine
  • Propofol
• Nurse responsibilities:
  • Monitor vital signs continuously
  • Ensure resuscitation equipment available
  • Document pre- and post-reduction assessment
  • Educate parents about post-reduction monitoring

Post-Reduction Management:

• Observation for 2-4 hours after successful reduction
• Ensure child can tolerate oral intake
• Schedule urgent surgical repair (usually within 24-48 hours)
• Provide clear instructions to parents regarding warning signs

Assessment:

• Complete physical assessment, focusing on:
  • Characteristics of the hernia (size, location, reducibility)
  • Vital signs
  • Hydration status
  • Abdominal assessment
  • Pain level (age-appropriate scale)
• Review medical history and identify risk factors:
  • Prematurity
  • Previous surgeries
  • Congenital anomalies
  • Conditions causing increased intra-abdominal pressure
• Evaluate nutritional status
• Assess family understanding and concerns

Interventions:

• Prepare child and family for surgery:
  • Age-appropriate education about the procedure
  • Tour of surgical area if possible
  • Discuss expected postoperative course
• Implement preoperative fasting guidelines:
  • Clear liquids: Up to 2 hours before surgery
  • Breast milk: Up to 4 hours before surgery
  • Formula/light meals: Up to 6 hours before surgery
• Complete preoperative checklist and documentation
• Administer preoperative medications as ordered
• Provide emotional support to child and family

Discharge Instructions:

• Wound care:
  • Keep incision clean and dry
  • Steri-strips typically fall off in 7-10 days
  • Showers usually allowed after 48 hours; avoid tub baths for 5-7 days
• Pain management:
  • Schedule for prescribed pain medications
  • Signs of pain in younger children
  • Non-pharmacological pain relief strategies
• Activity restrictions:
  • No strenuous activity, heavy lifting, or sports for 2-4 weeks
  • Return to school/daycare typically in 2-7 days
  • Age-appropriate guidance for play

Warning Signs (When to Call Provider):

• Fever > 38.5°C (101.3°F)
• Increased redness, swelling, or drainage from incision
• Persistent or increasing pain not relieved by medication
• Inability to urinate within 8-12 hours after surgery
• Persistent vomiting or inability to tolerate fluids
• For boys with inguinal hernia repair: significant scrotal swelling or discoloration

Follow-up:

• Schedule for postoperative visit (typically 1-2 weeks)
• Importance of keeping follow-up appointments
• Contact information for questions or concerns

Premature Infants:

• Higher risk of inguinal hernias (up to 30%)
• Increased incidence of bilateral hernias
• Timing of repair considerations:
  • Some surgeons repair before NICU discharge
  • Others wait until infant reaches certain weight (typically 2-2.5 kg)
  • Risk of postoperative apnea if repaired before 60 weeks post-conceptional age
• Nursing implications:
  • Careful monitoring for apnea and bradycardia post-repair
  • Attention to thermoregulation
  • Special considerations for pain assessment and management
  • Careful attention to nutrition and hydration

Children with Connective Tissue Disorders:

• Increased risk of:
  • Hernia development
  • Recurrence after repair
  • Bilateral hernias
• Conditions of concern:
  • Ehlers-Danlos syndrome
  • Marfan syndrome
  • Osteogenesis imperfecta
• Nursing implications:
  • Careful tissue handling during care
  • Extended activity restrictions may be needed
  • Vigilant monitoring for recurrence
  • Education regarding increased lifetime risk

Children with Chronic Constipation or Cough:

• Increased risk of developing hernias due to increased intra-abdominal pressure
• Higher recurrence risk after repair
• Management strategies:
  • Treat underlying condition aggressively
  • Stool softeners to prevent constipation
  • Cough suppression when appropriate
  • Extended activity restrictions may be considered

Children with Ventriculoperitoneal Shunts:

• Increased risk of inguinal hernias due to increased intraperitoneal fluid
• Special considerations:
  • Monitor shunt function before and after repair
  • Coordinate care with neurosurgery team
  • Monitor for signs of increased intracranial pressure
  • Risk of shunt infection if peritoneal contamination occurs