What are the key characteristics and management strategies for congenital diaphragmatic hernia, particularly in relation to emergency operation, types of hernias, and association with underlying lung pathology?

Congenital Diaphragmatic Hernia: Key Characteristics and Management

The Bochdalek hernia is the most common type of congenital diaphragmatic hernia (CDH), occurring in approximately 95% of cases, and typically requires surgical intervention when respiratory distress is present, though not always as an emergency procedure. 1

Types of Congenital Diaphragmatic Hernias

• Bochdalek hernia is the most common type of CDH (95%), occurring predominantly on the posterior left side of the diaphragm (85% left-sided vs. 15% right-sided) 1
• Morgagni hernia is less common and typically presents with more subtle symptoms rather than acute respiratory distress in adults 1, 2
• CDH results from incomplete development of the diaphragm during the eighth week of gestation 1

Clinical Presentation and Diagnosis

• In newborns, CDH commonly presents with severe respiratory distress due to pulmonary hypoplasia caused by the presence of abdominal organs in the chest cavity during prenatal development 1, 3
• In older children and adults, CDH presentation is rare and may include chronic respiratory infections, vomiting, weight loss, or failure to thrive rather than acute respiratory distress 4
• CT scan of the chest and abdomen is the gold standard for diagnosing diaphragmatic hernia 1
• Physical examination may reveal absence of breathing sounds or presence of bowel sounds in the chest 4, 2

Management Approach

• For patients with CDH presenting with respiratory distress, prompt surgical intervention is necessary but not always as an emergency procedure 1, 5

• Modern management strategies for newborns with CDH and respiratory distress often include:

  • Permissive hypercapnea/spontaneous respiration followed by elective repair rather than emergency surgery 5
  • Appropriate preoperative assessment and stabilization before surgical intervention 1

• For complicated CDH in unstable patients:

  • Open surgical approach (laparotomy) is recommended 1, 6
  • Damage Control Surgery can be life-saving in critically unstable patients 1

• For stable patients with complicated CDH:

  • Minimally invasive approach (laparoscopic) is preferred 1, 6
  • This approach has an excellent safety profile with reported in-hospital mortality rate of only 0.14% 1

Associated Conditions and Complications

• CDH is strongly associated with underlying lung pathology, particularly pulmonary hypoplasia and persistent pulmonary hypertension 3, 7
• About one-third of CDH cases have cardiovascular malformations 3
• Postoperative complications may include:
  • Gastric atony (reported in up to 58% of survivors in some series) 4
  • Chronic respiratory tract disease 3
  • Neurodevelopmental problems 3
  • Gastroesophageal reflux (up to 62% incidence after repair) 1

Important Considerations in Surgical Repair

• For large defects (>8 cm or >20 cm²), mesh reinforcement is recommended 1, 6
• Tackers should be avoided near the pericardium due to risk of cardiac complications 1
• The chronicity of the condition is a primary factor in determining the best surgical approach 6
• Right-sided diaphragmatic hernias may require specialized approaches due to the presence of the liver 1, 6