Traumatic Delivery, Diaphragmatic Paresis, and “Dextrocardia”

A term male infant weighing 4170 g was delivered vaginally, by forceps extraction. Apgar scores and cord blood pHs were normal. He was noted to have a left-sided Erb's palsy, tachypnea, and mild chest recession. Oxygen saturations were 87% in room air, and the initial chest radiograph showed an elevated left hemi-diaphragm with mediastinal shift to the right (Figure). Fluoroscopy screening of the diaphragm demonstrated paradoxical movement of the left hemi-diaphragm consistent with left diaphragmatic paresis. He improved clinically and was discharged home after 9 days. Both the diaphragmatic paresis and the Erb's palsy had resolved by 3 months of age.

View Large Image Download to PowerPoint

Figure. Chest radiograph demonstrating markedly elevated left hemi-diaphragm with shift of heart and mediastinum to the right.

Diaphragmatic paresis is an infrequent cause of neonatal respiratory distress and is usually caused by phrenic nerve injury from traumatic delivery.1 It may be associated with brachial plexus injury, especially in infants with shoulder dystocia or breech delivery. The incidence of neonatal phrenic nerve paralysis caused by traumatic delivery is unknown. Clinical presentation is variable. Most reported cases required assisted ventilation with either continuous positive airway pressure or intermittent positive pressure ventilation. A significant proportion required surgical intervention in the form of diaphragmatic plication.1, 2, 3 Phrenic nerve palsy may also present outside the neonatal period with subtle symptoms. Milder cases may be under-reported.1, 2

In comparison with many reported cases, this infant had a mild clinical course.1, 3, 4 Spontaneous clinical recovery occurred within weeks and radiographic resolution occurred within 3 months. On chest radiography, the initial diaphragmatic paresis was accompanied by mediastinal shift, mimicking dextrocardia, and the patient was hypoxic. Few reported cases presenting with hypoxia and “dextrocardia” on chest radiography have been described. This presentation may mislead the physician by mimicking congenital heart disease.5