Congenital Diaphragmatic Hernias Treatment & Management

Resuscitation with ventilatory support is of prime importance in patients born with CDH. The trend over the past few years has been a switch from conventional mechanical ventilation to high-frequency oscillatory ventilation (HFOV). HFOV serves to minimize airway pressure and, in conjunction with permissive hypercapnia, HFOV helps those with CDH suffer less traumatic lung injury and fewer long-term complications. Mortality has been shown to decrease from 49-20% when HFOV is used early in the treatment course.{Ref30}

Extracorporeal membrane oxygenation (ECMO) has been shown to significantly decrease the mortality of CDH but is currently reserved for individuals whose condition fails to improve with both HFOV and conventional mechanical ventilation. The decision to utilize ECMO is made early in the disease process, usually within 24 hours of birth.

With the addition of HFOV, more reports exist of decreased morbidity and mortality with early surgical intervention. However, this practice is still rather controversial. The classical teaching is that patients need to be stabilized (often with the use of ECMO) and that repair be delayed until the infant is better prepared to survive the operation.^[12]

• Congenital (perinatal period): Significant issues remain, and many questions are unanswered, but the possibility of maternal-fetal surgical treatment of congenital diaphragmatic hernia is on the horizon.^{[13, 14]}
• Congenital (neonatal period): A subcostal incision is used. An attempt is made to repair the hernia with a primary repair; however, a prosthetic material such at ePTFE or polypropylene must sometimes be used.
• Congenital (latent): Approach is through thoracotomy or laparotomy. Most surgeons approach with laparotomy so that abdominal contents can be inspected adequately. Minimally invasive approaches are currently being explored via video-assisted thoracoscopic or laparoscopic approach.

• Congenital (neonatal period): Reduce the abdominal contents, then approximate the edges of the diaphragm with nonabsorbable suture. If the defect is large or the repair is being made while the patient is on ECMO, prosthetic mesh is used.
• Congenital (latent): This typically is repaired with prosthetic mesh in children and direct suture technique in adults with nonabsorbable suture material. Minimally invasive repair is being explored at a number of institutions.
• Traumatic rupture:^{[15, 16, 17]} The surgical approach depends on the timing of the diagnosis with the surgical intervention.^[14]

Once an anatomic defect has been corrected, periodically assessing pulmonary function and obtaining chest radiographs is important. Although spontaneous recurrence of a repaired diaphragmatic hernia is low, small defects in the repair site have been reported, so surveillance is essential.

• Congenital defects: Remembering that an increased risk of concomitant congenital defects in an infant with CDH is extremely important. If a diaphragmatic hernia is diagnosed in utero, have a high suspicion for concomitant abnormalities. Always remember that the infants with CDH have an increased risk of postnatal respiratory failure, incarceration or strangulation of bowel, and hypoplasia of lung.^[18]
• Traumatic or adult repaired CDH: Recurrence of the hernia is possible; thus, follow-up is important with chest radiograph.

With the development of newer treatment techniques to include HFOV and more sophisticated extracorporeal oxygenation equipment, the mortality rate of CDH has continually decreased.^{[19, 20, 21, 22]} However, long-term morbidity includes such entities as gastroesophageal reflux disease (GERD), neurologic and development disorders, and musculoskeletal orders.^[23]

New research currently is underway using inhaled nitric oxide, partial liquid ventilation, and the possibility of lung transplantation for infants born with severe hypoplasia.^[23] Minimally invasive repair techniques for latent CDH are being explored at a number of institutions.

Some centers use intrauterine fetal surgery (fetoscopy) to repair diaphragmatic defects in an attempt to prevent the hypoplastic lung problems encountered with large hernias.^[23] Because the number of cases performed is still small and very few centers are capable of performing intrauterine surgery, this practice is rather controversial. Preterm rupture of membranes remains the weak link of fetoscopy. Refinement of the technique of fetoscopy and technologic advances such as partial amniotic carbon dioxide insufflation will help correct this problem and may allow the application of fetoscopy for other pathologies in the future.^{[24, 14, 13]}