A congenital diaphragmatic hernia (CDH) is a failure of the diaphragmatic tissue to fuse, resulting in a defect that allows abdominal contents to herniate into the thoracic cavity. The main issue with congenital diaphragmatic hernias is respiratory insufficiency due to hypoplasia of the ipsilateral lung and pulmonary hypertension. It commonly occurs on the left.
70% of patients with a congenital diaphragmatic hernia die within the first year of life
Types of congenital diaphragmatic hernia
| Type | Description |
|---|---|
| Posterolateral defect | Also known as a Bochdalek hernia. Accounts for 95% of hernias. The majority occur on the left |
| Non-posterolateral defect | Anterior defect (Morgagni hernia) is the most common. Accounts for 2 – 3 %. May be discovered later in life since they are smaller defects |
- Signs and symptoms
- Respiratory distress
- Scaphoid abdomen
- Shift of heart sounds to the right
- Tachypnea
- Bowel sounds or absent breath sounds on the affected side
- Pulmonary hypertension
- Investigations
- Prenatal ultrasound
- Polyhydramnios (75% of fetuses with CDH)
- Absent stomach bubble or stomach bubble in the chest
- Bowel loops in the chest
- Mediastinal shift from the side of the hernia
- Hydrops fetalis (edema in 2 of 4 of fetal spaces – skin, pericardium, pleural space, peritoneal cavity)
- Chest X-ray
- Abdominal contents in the thoracic cavity, typically in the left(cystic lucencies)
- Mediastinal shift
- Lung hypoplasia
- Compressive atelectasis
- Lung-to-head ratio: product of the length and width of the right lung at the level of the cardiac atria divided by the head circumference (all measurements in millimeters)
- < 1.0 is commonly fatal
- ≥ 1.4 is favourable
- Prenatal ultrasound
- Treatment
- NICU care
- Nasogastric tube for decompression
- Intubation and gentle mechanical ventilation
- Allow a bit of hypercapnia – PaCO2 50 – 60 mmHg if pH remains > 7.25
- Adjuncts
- Inhaled nitric oxide
- High-frequency oscillatory ventilation (HFOV)
- Extracorporeal membrane oxygenation (ECMO)
- Intravenous fluids and glucose
- Delay surgery for 24-48 hours to allow for improvement of pulmonary hypertension
- Factors associated with poor prognosis
- Associated anomalies
- Prematurity
- Poor APGAR score
- Early pneumothorax
- High degree of pulmonary hypoplasia and pulmonary hypertension
