Acquired diaphragmatic hernia in a preterm low birth weight neonate

Introduction

We refer to your recent article on diaphragmatic hernia in children. ¹ Iatrogenic diaphragmatic hernia is rare in children and we report a preterm low birth weight neonate with a presumably acquired diaphragmatic hernia due to trauma caused by treatment following pneumothorax.

Case report

A preterm, low birth weight (30 weeks of gestation, 1.515 kg birth weight) female infant, delivered vaginally, was transferred for respiratory distress. There was no perinatal asphyxia. Initial chest radiography revealed Hyaline membrane disease with no other abnormality (Figure 1). Surfactant was administered and the baby was placed on bubble continuous positive pressure ventilation. Despite this, persistent respiratory distress continued; therefore, endotracheal intubation and mechanical ventilation were carried out. After an initial period of improvement on low inspiration volumes, respiratory distress resumed. This time a chest X-ray revealed a tension left pneumothorax (Figure 2). Emergency needle thoracostomy was followed by Ch10 intercostal drain (ICD) insertion in the fifth left intercostal space along the anterior axillary line. A post-insertion chest X-ray showed a resolving pneumothorax (Figure 3) and the child was gradually weaned off invasive ventilation. The ICD was then removed, but respiratory distress again recurred over the next few hours. A further chest X-ray now revealed a left-sided diaphragmatic hernia with herniation of bowel contents into left hemithorax with displacement of left lung and mediastinum to opposite side (Figure 4). At emergency laparotomy, the left diaphragmatic hernia was evident with a defect in posterolateral part of diaphragm. The hernial sac contained the spleen, the splenic flexure of colon, the left kidney and a part of transverse colon. Abdominal contents were reduced, the defect repaired and expansion of all left lung lobes was noted. The baby subsequently made an uneventful postoperative recovery and was discharged after adequate weight gain. OPEN IN VIEWER

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Figure 2.

Chest X-ray showing left pneumothorax with mediastinal shift to opposite side.

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Figure 3.

Chest X-ray showing resolving pneumothorax after ICD insertion.

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Figure 4.

Chest X-ray showing left-sided diaphragmatic hernia with herniation of bowel contents into left hemithorax.

Discussion

There are two well recognised sites where abdominal viscera normally herniate into the chest before birth, the commoner being the foramen of Bockdaleck, posteriorly through the dome of the diaphragm, and the other through the foramen of Morgagni, anteriorly. ² Acquired diaphragmatic hernias in babies are extremely uncommon. Various causes include blunt or penetrating trauma. Catastrophic consequences may ensue if the diagnosis is missed or left untreated. An acquired diaphragmatic hernia in a six-month-old baby from traumatic introduction of an ICD has been recorded. ³

In our case, aggressive ventilation may probably have caused the initial pneumothorax, which prevented herniation of abdominal contents. Once the pneumothorax was treated, there was then space for the spleen, intestine and kidney to migrate into the left hemithorax. Hypoplasia usually only occurs where herniation predates birth or presentation, unlike in this case.

An alternative explanation is traumatic penetration of the diaphragm by ICD insertion. This was, alas, carried out using a trocar, which is a method no longer recommended for this very reason.

Timely management of diaphragm defects is life-saving.