How is a congenital left posterolateral diaphragmatic (Bochdalek) hernia presented and managed in neonates and adults?

Bochdalek Hernia: Presentation and Management

Definition and Epidemiology

Bochdalek hernia is a congenital posterolateral diaphragmatic defect that accounts for approximately 95% of all congenital diaphragmatic hernias, occurring on the left side in 85% of cases and the right side in 15%. 1

• The incidence in neonates is approximately 1 in 2000 to 3000 live births 2
• Adult presentation is rare, with an incidence of only 0.17% and typical diagnosis around 40 years of age 1
• The defect results from incomplete diaphragmatic development during the eighth week of gestation 3

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Clinical Presentation

Neonatal Presentation

Neonates present with severe respiratory distress immediately after birth due to pulmonary hypoplasia and persistent pulmonary hypertension. 2

• Respiratory failure is the primary cause of morbidity and mortality, resulting from hypoplastic lungs compressed by herniated abdominal organs during prenatal development 3
• Pulmonary hypertension coexists in approximately 63% of CDH patients 1
• When pulmonary hypertension is present, mortality rises to 45% 1
• Right-sided hernias are particularly difficult to diagnose, as the liver may mimic pleural effusion or pulmonary consolidation on imaging 4

Adult Presentation

Adults typically present with nonspecific gastrointestinal and respiratory symptoms that can remain asymptomatic for decades before becoming clinically apparent. 5

• Common symptoms include dyspnea, abdominal pain, nausea, vomiting, and dysphagia 6
• Gastrointestinal symptoms predominate in left-sided hernias, including intestinal obstruction 5
• Life-threatening complications include organ incarceration, strangulation, volvulus, perforation, respiratory failure from lung compression, and cardiac tamponade from heart compression 1, 4
• Misdiagnosis is common—patients may be incorrectly treated for pneumonia, bronchiolitis, or chronic bronchitis for extended periods 7
• Delayed diagnosis occurs in 5–45% of all congenital diaphragmatic hernias 5

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Diagnostic Approach

Computed tomography of the chest and abdomen is the diagnostic gold standard for evaluating Bochdalek hernia in both neonates and adults. 4

• In neonates and patients with respiratory symptoms, chest X-ray (anteroposterior and lateral) is recommended as the first diagnostic study 5
• Routine echocardiography is mandatory for every CDH patient to assess pulmonary hypertension severity and identify associated congenital heart disease 1, 4
• The diagnosis is frequently missed in acute settings because the condition is rare and clinical findings are nonspecific 4

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Management

Neonatal Management

Immediate endotracheal intubation is mandated to keep peak inspiratory pressures low and avoid large tidal volumes (Class I recommendation). 1, 4

Ventilation Strategy:

• Minimize peak inspiratory pressure and avoid large tidal volumes to prevent barotrauma 4
• High-frequency oscillatory ventilation is reasonable when lung compliance is poor, tidal volumes are low, and gas exchange is inadequate (Class IIa) 1, 4

Medical Therapy:

• Inhaled nitric oxide may improve oxygenation in severe pulmonary hypertension but should be used cautiously if left-ventricular dysfunction is suspected (Class IIa) 1, 4
• Extracorporeal membrane oxygenation (ECMO) is recommended for patients with severe pulmonary hypertension unresponsive to medical therapy (Class I) 1, 4

Surgical Timing:

• In neonates, surgery is performed to prevent complications of pulmonary hypoplasia after initial stabilization 6

Adult Management

All complicated diaphragmatic hernias require surgical repair; the operative approach is dictated by hemodynamic stability. 4

Surgical Approach Selection:

For hemodynamically stable patients, laparoscopic repair is preferred because it enables early detection of small diaphragmatic injuries and is associated with fewer postoperative complications. 1, 4

Open repair is indicated when:

• The patient is hemodynamically unstable 4
• Exploratory laparotomy is required 4
• Laparoscopic expertise or equipment is unavailable 4
• Damage-control surgery is necessary 4

Mesh Reinforcement:

• Biological and bio-absorbable meshes are preferred for diaphragmatic reinforcement because they reduce recurrence rates compared with synthetic alternatives 1

Conservative Management:

• In adults, surgical correction is primarily for symptomatic management 6
• Conservative management may be considered in elderly patients with significant comorbidities who decline surgery, though this carries risk of life-threatening complications 6

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Key Clinical Pitfalls

• Never delay diagnosis by attributing respiratory symptoms to common conditions like pneumonia or bronchiolitis in neonates 5
• Do not miss right-sided hernias—the liver can masquerade as pleural pathology 4
• Always obtain echocardiography to assess for pulmonary hypertension, as it directly impacts mortality 1
• Avoid bag-mask ventilation in neonates—this can worsen gastric distension and further compromise respiratory function; proceed directly to endotracheal intubation 1