Physical findings may include decreased or absent breath sounds on the affected
side , a scaphoid or flat abdomen, shift of the cardia PMI.
.
Recent literature have described prenatal anatomic parameters that predict a
baby who may have difficulty with pulmonary hypertension. These include having an
intrathoracic stomach and/or liver. In a left sided CDH baby, having a lung/head ratio
(taken at EGA 24 - 26 weeks) predicts usually associated with a larger diaphragmatic
defect and a smaller lung (sicker baby).
Babies with CDH vary from those who do not require O2 to those who require
significant help with regard to oxygenation, ventilation, and even cardiac support. The
main reason for the physiologic problems of a baby with CDH stem from increased
pulmonary vascular resistance and pulmonary hypertension. The media layer of the
pulmonary arteries in a baby with CDH contain more smooth muscle cells that are
comparatively larger in size than those of a baby without CDH. These cells are also
more sensitive than normal to factors that cause vasoconstriction, namely, hypoxia,
academia, and hypercarbia. As previously mentioned, the lungs of babies with CDH has
a decreased cross sectional arterial surface area due to the smaller number of
branching seen with lung units. Cardiac dysfunction from hypoxia, ventricular
hypoplasia, or right heart dysfuction may increase pulmonary venous pressure and
PVR.