Fetal Intervention
Fetuses on the most severe end of the spectrum with liver up and LHR less
than 1.0 are candidates for prenatal intervention. For more than two decades,
we have been working on ways to improve the outcome for these fetuses by
getting the lung to grow before birth, so that it will be adequate at the
time of birth. The most promising uses FETENDO fetal surgery, specifically a fetoscopic temporary
tracheal occlusion to enlarge the lung.
While in the uterus, the fetal lung
constantly makes fluid that escapes through its mouth and into the amniotic
fluid. When the trachea is blocked, this fluid stays in the lungs. As it
builds up, the lung fluid expands the lungs, stimulates their growth, and
pushes the abdominal contents (liver, intestine) out of the chest and into
the abdomen. The goal of this treatment is to have a baby born with lungs
that are big enough that the child can breathe and provide itself enough
oxygen to breath on its own.
Minimally Invasive Surgery: Tracheal Occlusion
The FTC at UCSF has long been the world leader in treatment for CDH. We
have received approval (an investigational device exemption) to use a
new medical device for tracheal occlusion in severe CDH. We have the
only significant experience with tracheal occlusion in the United
States, having performed a prospective randomized trial in the past
sponsored by the NIH and published in the New England Journal of
Medicine. Although we did not find a difference between the tracheal
occlusion group and the control group, we learned much from the trial.
We offer tracheal occlusion to a select group of patients that we feel
have the most to potentially benefit from this procedure.
Using only a tiny keyhole incision in the mother and mother's
uterus, and a tiny detachable balloon is placed in the fetal trachea.
Once the fetal lung has grown, the balloon can be removed or deflated
so the baby can be born normally. Both insertion and removal os the
tracheal occlusion happens before birth; as a result, mothers can
deliver vaginally without need for an EXIT procedure in most cases. We
feel that this more minimally invasive strategy will allow mothers to
stay pregnant longer and avoid the complications of preterm labor
associated with previous attempts at tracheal occlusion.
Who is a candidate for balloon tracheal occlusion?
Balloon
tracheal occlusion is only offered to those patients whose fetus have
the most severe form of congenital diaphragmatic hernia. We have
defined this group as: 1) a part of the liver has moved into the fetal
chest cavity, and 2) the measured lung on the right side (not the side
of the hernia) is small and has a lung to head ratio (LHR) of less than
or equal to 1.0
In order to be considered for fetal intervention, you must first
undergo an amniocentesis to determine that there are no chromosome
problems with the fetus. The results of this test usually takes 7-10
working days.
Inclusion criteria
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Exclusion criteria |
- Confirmed CDH with a portion of the liver herniated into the chest
- LHR less than or equal to 1.0
- normal amniocentesis
- no other birth defects
- Less than 28 weeks' gestation
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- abnormal amniocentesis results
- fetus has another birth defect
- Mother has a contraindication to general anesthesia
- placenta previa
- short cervical length (< 2.0cm)
- BMI > 35
- Abnormal uterus
- Preterm labor
|
UCSF formal evaluation
If you meet all these criteria and wish to be considered for
tracheal occlusion you will need to travel to San Francisco for a
formal evaluation. A formal evaluation would include: an ultrasound (to
determine liver position and LHR), and ECHO (ultrasound of the heart to
rule out any abnormalities), and counseling by a number of the members
of our Fetal Treatment Center team (surgeon, social worker,
perinatologist, nurse, etc).
The balloon tracheal occlusion operation
If you are found to be a tracheal occlusion candidate, and you chose
to undergo the procedure, the tracheal occlusion operation will be
performed between the 26th and 28th week of your pregnancy. The
procedure requires an overnight hospital stay. After discharge from the
hospital you will need to stay in San Francisco while the balloon is in
your fetuses' trachea. This is usually for a period of 4 weeks. During
this time you would have weekly ultrasound and medical appointments.
After 4 weeks you would again enter the hospital for an overnight stay
to have the balloon removed from the fetal trachea. If the procedures
are successful, you could return home to deliver.
Insurance pre-authorization requirement
Both the evaluation and the operations need to be authorized by your
insurance company. Most insurance companies have paid for this
procedure for their insured. You should contact your insurance company
to determine whether pre-authorization is required. We can provide your
with the diagnosis and procedures codes.
For more information please contact our center.
What will happen after birth?
All babies with CDH should be delivered at a tertiary perinatal center
with a high-level intensive care nursery and pediatric surgery. Although
some babies with a very favorable outlook (LHR > 1.4) will not need very
high level intensive care, most should be cared for by neonatologists and
surgeons in an ICN experienced in high frequency and oscillation ventilation,
nitric oxide inhalation, and particularly extracorporeal membrane oxygenation
(ECMO). It is not possible to tell before birth how much support any baby
will need after birth. Babies with CDH known before birth should never be
delivered in an institution incapable of providing all the support needed:
transporting a sick baby is dangerous.
All babies with CDH should be delivered into a “set-up” where
the neonatologists take the baby from the obstetricians and immediately
provide life support—breathing, oxygen, IV fluids, etc., as needed. The baby’s
response will determine the amount of breathing support is needed, ranging
from a little oxygen to a breathing machine to ECMO.
The severity of the lung problem will also determine the course in the
intensive care nursery—again, ranging from surgical repair in the first
day and home in a few weeks, to full support including ECMO for weeks, surgical
repair (sometimes done while the baby is on ECMO), and then months of very
intensive support before going home.
The long-term outcome depends on this need for very intensive support.
