Lung hypoplasia in congenital diaphragmatic hernia: A quantitative study of airway, artery, and alveolar development

Abstract

From a case of congenital diaphragmatic hernia the pattern of growth of the airways, alveoli, and pulmonary arteries of both lungs, each hypoplastic, has been analysed quantitatively. The impairment of growth for each type of structure is not necessarily the same and differs in each lung. Airway and alveolar numbers are both greatly reduced, although the latter are more nearly normal when related to the number of terminal bronchioli in the lung. In each lung the size of the pulmonary artery at the hilum is appropriate to the lung volume but small for the age of the child. Muscle is found in much smaller arteries than is normal but not to a more peripheral level. The way the lungs in a case of congenital diaphragmatic hernia might grow after surgical correction of the hernia is discussed and a plea made for respiratory physiological studies in such cases.

Pulmonary vascular resistance in repaired congenital diaphragmatic hernia vs. age-matched controls

“…Histological studies of lung parenchyma in these patients have shown a reduced total pulmonary vascular bed with decreased numbers of vessels per unit lung. Medial hyperplasia of the pulmonary arteries together with peripheral extension of the muscle layer into the small arterioles has also been noted (12)(13)(14)(15)(16). Further, in the CDH lung, there is failure of arterial wall thinning associated with normal newborn pulmonary arterial remodeling (14).…”

Prenatal diagnosis of primary pulmonary hypoplasia in fraternal twins

“…However, the pulmonary arteries were reduced in size for the airways, making a defect in pulmonary artery development a possible etiology. In lung hypoplasia due to congenital diaphragmatic hernia, where there is a reduced number of airway generations, intrapulmonary artery size is normal relative to the airways and lung volume, but there is an increase in muscular wall and adventitia 16,17 . In renal agenesis, increased pulmonary artery size relative to lung volume has been described 18 .…”

Congenital diaphragmatic hernia: a systematic review and summary of best-evidence practice strategies

“…1 The combination of pathophysiologic derangements associated with CDH, including lung hypoplasia, lung dysmaturity and pulmonary hypertension (PPHN), requires a multidisciplinary approach to care. 2,3 The complex nature of clinical management and the relatively infrequent presentation of infants with this rare malformation to single centers has lead to difficulty identifying consistent strategies for CDH management. A recent report from the Canadian Neonatal Research Network indicates better than predicted survival in Network centers, with significant improvement in the higher mortality odds strata, and 90% survival in the three centers that cared for at least 12 infants over a 22-month period.…”