Congenital Diaphragmatic Hernia (CDH)

Question 1

Describe ultrasound findings in a fetus with CDH.

Answer 1

Left sided CDH -> stomach is posterior and heart is displaced to the right.

Right sided CDH -> stomach below diaphragm but midline.

Bilateral CDH.

Question 2

On which side are congenital diaphragmatic hernia more common?

Answer 2

75% are left sided
15% are right sided
10% bilateral

Question 3

Maternal risk factors for CDH.

Answer 3

Smoking
Alcohol
Anticonvulsants

Question 4

What genetic conditions are associated with CDH?

Answer 4

T18
T13
T21
\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_
10-20% in utero 
40-60% in live born infant 
95% in IUFD

Question 5

What work-up do you perform if a CDH is identified?

Answer 5

Detailed fetal anatomic survey 
Fetal echocardiogram
Amniocentesis 
Fetal growth 
MRI 
Pediatric surgery 
Antenatal testing at 32 weeks

Question 6

What percentage of CDH will have an associated genetic condition or karyotype abnormality?

Answer 6

10-20%

Question 7

How do you counsel a patient if a CDH is identified on ultrasound?

Answer 7

• Less than 24 weeks, termination can be considered
• Associated with cardiac, GI anomalies
• Survival is 80% without liver herniation
• Survival is 50% with liver herniation
• Polyhydramnios if esophageal compression

Question 8

What are potential fetal complications that can develop as a result of CDH?

Answer 8

Polyhydramnios
Pulmonary hypoplasia and pulmonary hypertension
Cardiac anomalies
GI anomalies

Question 9

How do you follow a pregnancy complicated by CDH?

Answer 9

Serial ultrasounds to assess for liver herniation after detailed anatomic survey and fetal echocardiogram and amniocentesis. Assess lung volume using the LHR.
________
Fetoscopic endoluminal occlusion if singleton pregnancy, normal karyotype and no associated anomalies with LHR <1

Question 10

What factors on ultrasound are associated with worse prognosis for CDH?

Answer 10

• Liver herniation
• Decreased lung volume
• Posterior and retrocardiac stomach

Question 11

What is the lung area to head circumference ratio?

Answer 11

area of the lung contralateral to the herniation (mm)/ head circumference (mm)

it helps to predict poor outcome due to association with pulmonary hypoplasia

Question 12

Describe how you calculate the LHR

Answer 12

area of the lung contralateral to the herniation (mm)/ head circumference (mm)

Question 13

How do you interpret LHR results

Answer 13

Less than 1 -> worse prognosis (10-15% survival and 75% will need ECMO) also true if E/O is less than 25%
Greater than 1.4 –> better prognosis. Also true if expected/observed is greater than 45%

Question 14

What are the long term complications of CDH?

Answer 14

Pulmonary hypoplasia
Musculoskeletal disease
GI disease
Neurodevelopmental abnormality in 20-30%