Congenital Diaphragmatic Hernia From Prenatal Diagnosis to Surgery

Congenital diaphragmatic hernia (CDH) is a developmental defect in the diaphragm that allows abdominal organs to move into the chest. The resulting compression can limit lung growth and interfere with pulmonary vascular development. Although the anatomical defect can often be identified before birth, the clinical course varies widely, from relatively mild respiratory disease to severe pulmonary hypoplasia and persistent pulmonary hypertension.

Care now depends on a coordinated pathway. Fetal imaging, genetic assessment, maternal counseling, delivery-room stabilization, neonatal intensive care, and surgical repair must be connected rather than treated as separate events. Families benefit when clinicians explain both the seriousness of the diagnosis and the considerable variation in outcomes.

The FAOPS 2020 congress website, created for a meeting focused on perinatal and neonatal medicine in Tokyo, remains a useful example of how specialists share research and clinical perspectives across disciplines. Its FAOPS 2020 congress site also reflects the international setting in which advances in fetal diagnosis, neonatal resuscitation, and pediatric surgery are discussed.

Why prenatal recognition matters

Most cases of CDH are detected during the second-trimester anatomy scan or during a targeted examination prompted by an abnormal finding. The sonographic appearance may include herniation of the stomach, bowel, liver, or spleen into the thorax, mediastinal shift, and reduced visible lung tissue. A left-sided defect is more common, while right-sided disease can be harder to identify because the liver and lung have similar ultrasound characteristics.

Prenatal diagnosis gives the clinical team time to clarify the anatomy and estimate the expected severity. It also allows referral to a fetal medicine unit with neonatal intensive care, pediatric surgery, pediatric cardiology, anesthesia, and respiratory support expertise. When CDH is recognized only after birth, emergency stabilization may occur before the right resources are assembled.

The diagnosis can also reveal associated conditions. Cardiac abnormalities, chromosomal differences, genetic syndromes, and additional structural defects may influence counseling and treatment decisions. A detailed fetal survey, fetal echocardiography, and a discussion of diagnostic testing are therefore important parts of evaluation, especially when the hernia is accompanied by other abnormalities.

Imaging severity and fetal assessment

Ultrasound remains central to the assessment of fetal CDH. Clinicians evaluate the side of the defect, the organs in the chest, the degree of mediastinal displacement, and the amount of liver herniation. Liver-up disease is generally associated with greater thoracic compression, although no single finding can predict an individual infant’s outcome with certainty.

The observed-to-expected lung-to-head ratio, or o/e LHR, is commonly used to estimate the amount of residual lung tissue. Measurements are interpreted according to gestational age, the side of the defect, and the imaging method. A lower value suggests more severe pulmonary hypoplasia, while a higher value is generally associated with a greater chance of survival without advanced support. The result should be presented as a risk estimate, not as a fixed forecast.

Fetal magnetic resonance imaging can add information when ultrasound findings are limited by maternal body habitus, fetal position, or uncertainty about liver position. MRI may provide a more comprehensive estimate of fetal lung volume and clarify the distribution of herniated organs. Serial examinations are useful because the relative size of the lungs and the position of abdominal organs can change as pregnancy progresses.

Assessment should also include fetal growth, amniotic fluid, cardiac function, and signs of hydrops. These findings help distinguish isolated CDH from a broader fetal disorder. Multidisciplinary review is especially valuable when imaging results are borderline or when parents are considering options such as fetal intervention.

Counseling families about risk

Prenatal counseling should explain the anatomy in plain language before moving to survival statistics or treatment possibilities. Parents usually need to understand that the main threat is lung underdevelopment, with pulmonary hypertension and cardiac strain contributing after birth. The hole in the diaphragm can be repaired surgically, but closing it does not immediately reverse the effects of small lungs or abnormal pulmonary vessels.

Prognostic conversations should combine several findings: o/e LHR, liver position, defect side, associated anomalies, fetal growth, and the resources available at the planned delivery center. Families should hear about the likely need for intubation, prolonged ventilation, medication for pulmonary hypertension, nutritional support, and a delayed operation. They should also be told that neonatal progress can be unpredictable even when prenatal measurements appear reassuring.

Genetic counseling deserves a place in the same pathway. Isolated CDH may have a favorable genetic evaluation, but the presence of heart defects, skeletal abnormalities, brain findings, or growth restriction increases concern for an underlying syndrome or chromosomal condition. The choice of testing depends on gestational age, local practice, ultrasound findings, and parental preferences.

Preparing the delivery room

Timing and location of birth should be planned around fetal condition, gestational age, and access to specialist care rather than choosing early delivery simply because CDH has been diagnosed. In many cases, continuing the pregnancy to term or near term supports further lung development. Delivery should occur where neonatal ventilation, echocardiography, pediatric surgery, and extracorporeal membrane oxygenation can be accessed when appropriate.

Routine vaginal birth is often possible unless obstetric indications require another approach. A controlled delivery prevents the risks associated with an unnecessary premature birth. Before labor, the team should document the anticipated severity, assign roles, confirm blood products and equipment, and discuss whether the infant may need transfer after initial stabilization.

At birth, the infant should generally receive immediate airway control with endotracheal intubation rather than vigorous mask ventilation. Mask ventilation can force air into the stomach and bowel, increasing thoracic compression. A nasogastric or orogastric tube is placed for continuous decompression. Gentle ventilation using the lowest effective pressures helps reduce ventilator-induced lung injury in fragile hypoplastic lungs.

Initial stabilization includes monitoring oxygen saturation, heart rate, blood pressure, temperature, blood gases, and perfusion. Cord blood gas information can contribute to the first assessment of acid-base status and perinatal stress; discussion of cord blood gas analysis is relevant to broader delivery-room decision-making. In CDH, however, gas values must be interpreted alongside clinical examination, preductal and postductal oxygenation, echocardiography, and the infant’s response to support.

Stabilization before repair

The immediate objective is physiological stabilization, not rapid closure of the diaphragm. Ventilation strategies typically prioritize gentle pressures and acceptable carbon dioxide levels rather than forcing normal blood gases at the cost of lung injury. Sedation may reduce agitation and oxygen consumption, while vasoactive medicines support systemic perfusion when needed.

Pulmonary hypertension is assessed with echocardiography, which can show right-to-left shunting, right ventricular dysfunction, ductal flow patterns, and associated heart disease. Treatment may include optimized ventilation, oxygen, inhaled nitric oxide in selected cases, vasoactive support, and management of acidosis or hypothermia. The precise combination depends on the infant’s physiology rather than the diagnosis alone.

Some infants respond to conventional ventilation, while others need high-frequency ventilation or extracorporeal membrane oxygenation. ECMO can provide temporary heart-lung support when oxygenation or circulation remains inadequate despite maximal medical treatment. Eligibility depends on gestational age, weight, bleeding risk, neurological status, organ function, and local expertise.

Surgery is usually postponed until the infant has achieved relative stability. Common readiness indicators include improved gas exchange, manageable pulmonary pressures, stable blood pressure, adequate urine output, and reduced dependence on escalating support. Operating too early in an unstable infant may add physiological stress without correcting the underlying pulmonary hypoplasia.

Surgical repair and long-term care

The operation returns the abdominal organs to the abdomen and closes the diaphragmatic defect. A primary repair may be possible when the edges can be brought together without excessive tension. Larger defects may require a patch, and severe cases can involve a substantial abdominal-wall or thoracic size mismatch. The surgical approach, including open or minimally invasive techniques, is selected according to the infant’s stability, anatomy, and institutional experience.

Repair does not mark the end of treatment. Infants may need prolonged ventilation, careful fluid management, nutritional support, and surveillance for recurrent pulmonary hypertension. Feeding difficulties are common because of respiratory disease, reflux, altered gastrointestinal positioning, weakness, and prolonged hospitalization. A multidisciplinary team may include neonatology, surgery, pulmonology, cardiology, gastroenterology, nutrition, speech therapy, and developmental specialists.

Long-term follow-up should monitor recurrent hernia, chest-wall or spinal changes, gastroesophageal reflux, hearing, growth, neurodevelopment, and respiratory symptoms. Some children have exercise intolerance, chronic lung disease, or learning difficulties even after surviving the neonatal period. Early developmental assessment and family support can identify problems when intervention is most useful.

Priorities for a coordinated care pathway

• Confirm the anatomy with detailed ultrasound, fetal echocardiography, and MRI when it will improve decision-making.
• Refer the family early to a center with fetal medicine, neonatal intensive care, pediatric surgery, and advanced respiratory support.
• Use multiple prognostic findings rather than relying on a single lung measurement or liver-position result.
• Prepare a written delivery-room plan covering airway management, gastric decompression, ventilation targets, monitoring, and transfer procedures.
• Arrange structured follow-up for pulmonary, nutritional, developmental, cardiac, and surgical complications.

Prenatal diagnosis creates time for careful preparation, but it cannot remove every uncertainty. The most reliable care comes from repeated reassessment as gestation advances and from communication that keeps parents involved in decisions. Imaging, fetal therapy discussions, delivery-room stabilization, and surgery should be treated as stages of one continuous plan.

Clinicians and trainees can use the FAOPS resource to connect perinatal research with practical neonatal care, while families affected by CDH should be directed to a specialist center for individualized counseling. Early referral and a coordinated delivery-to-surgery pathway give each infant the strongest possible start.