Hernia diafragmática congénita / Congenital diaphragmatic hernia

The congenital diaphragmatic hernia (CDH) is a congenital defect of the formation and /or closure of the diaphragm that permits the herniation of abdominal contents into the thorax. It occurs when the diaphragmatic muscle fails to close during the prenatal development, and the contain of the abdomen migrate into the chest through this hole. When the abdominal organs are in the chest, there is limited room for the lungs to grow. This prevents the lungs for developing normally, resulting in pulmonary hypoplasia (or underdeveloped lungs). This can cause reduced blood flow to the lungs and pulmonary hypertension, as well as gastrointestinal reflux, feeding disorders and developmental delays. CDH can occur on the left side, right side or, very rarely, on both sides, and it can be life-threatening. The etiology is usually unknown. The incidence of CDH may be as high as 1 in 2000 to 1 in 5000 newborns alive. The sex relationship male/female is 1:1.8. Because of associated persistent pulmonary hypertension of the newborn and pulmonary hypoplasia, medical therapy in patients with CDH is directed toward optimizing oxygenation while avoiding definitive therapy. No time for repair of CDH is ideal, but it is suggested that the opportunity is 24-48 hours after birth to achieve pulmonary development. The key to survival lies in prompt diagnosis and treatment. Over the past two decades antenatal diagnosis rates have increased the knowledge of the pathophysiology of CDH and has become better understand with advances in clinical care including prenatal surgery, with a reported mortality of almost 35 % in live-born patients and a higher mortality when in utero deaths are conected. All these considerations are described in the article, with special reference to pre and post-natal treatment, complications management, diagnosis and prognosis

Vascular and ventilatory mechanical responses in three different stages of pulmonary development in the rabbit model of congenital diaphragmatic hernia

Abstract Purpose: To evaluate the vascular ventilatory response in different stages of lung development and to compare them to the neonates with congenital diaphragmatic hernia (CDH) in a rabbit model. Methods: New Zealand rabbits were divided into 8 groups (n=5): E25, E27, E30, and CDH. All groups were ventilated on a FlexiVent (Scireq, Montreal, QC, Canada), compounding the other 4 groups. The CDH surgery was performed at E25 and the harvest at E30. Dynamic compliance (CRS), dynamic elastance (ERS) and dynamic resistance (RRS) were measured every 4 min/24 min. Median wall thickness (MWT) and airspace were measured. ANOVA Bonferroni tests were used to perform statistical analysis. Significance was considered when p<0.05. Results: CRS was higher in E30 compared to all other groups (p<0.05). CRS and RRS of CDH and E27 were similar and were higher in E25 (p<0.05). MWT was decreased according to the gestational age, was increased in E27V and E30V (p<0.05) and decreased in CDHV (p<0.05), airspace was decreased in E25 and increased in all ventilated groups (p<0.05). Conclusions: The ventilation response of congenital diaphragmatic hernia is like the pseudoglandular stage of the lung development. These findings add information about the physiology of pulmonary ventilation in CDH.