Clinical Reference Systems: Pediatric Advisor 10.0
Transient Tachypnea of the Newborn (TTN)
DESCRIPTION
A newborn with transient tachypnea (TTN) has extra fluid in
his lungs which causes him to:
- breathe rapidly (more than 60 times a minute)
- pull in his chest wall with each breath (retractions)
- occasionally have a bluish tinge around his lips
(cyanosis), which indicates a need for extra oxygen.
This rapid breathing begins shortly after birth and the
baby's breathing rate usually becomes normal within 24 to
48 hours.
Another name for TTN is retained lung fluid.
CAUSE
A baby's lungs are normally filled with fluid while she is
inside the mother. After birth, the baby takes her first
breath and the lungs fill with air, replacing the fluid.
The baby's blood absorbs the lung fluid, or she coughs the
fluid out. The absorption process usually takes several
hours.
Some babies have extra fluid or absorb the fluid too slowly.
The fluid makes the lungs stiff, causing the baby to breathe
faster and harder than normal. As the fluid is absorbed, it
becomes easier to breathe and the baby's breathing rate
becomes normal.
The process of labor and vaginal birth squeezes the baby's
chest wall and prepares the lungs for the first breath.
Babies born by cesarean section (C-section) without labor or
babies born after fast labors are more likely to have TTN.
TREATMENT
- Special care nursery (SCN)
When newborns have breathing problems they are taken to
the SCN for observation and treatment. They are placed
on a warming bed. They are attached to a
cardiorespiratory monitor, which continuously records
their heart rate and respiratory (breathing) rate.
Often the babies are also attached to a monitor that
measures the oxygen level in the skin. This monitor is
called a pulse oximeter.
- Laboratory tests
To determine the cause of the breathing problem the baby
has blood tests and a chest x-ray. The blood tests
include a complete blood count (CBC), a blood culture to
look for signs of infection, and a blood gas
determination. This last test shows the level of oxygen
in the blood so your physician knows whether the baby
needs to be given extra oxygen.
- Oxygen
If the baby's color around the lips is bluish or the
blood gas determination and pulse oximeter readings
suggest the baby needs extra oxygen, he is placed in a
plastic hood into which extra oxygen is blown.
We breathe 21 percent oxygen in normal air. Most babies
with TTN will not need any extra oxygen. Some will need
only a small to moderate amount of extra oxygen (25 to
40 percent); rarely they may need up to 100 percent for
a short period of time. The most reliable signs that
the lung fluid is leaving the lungs are that the baby
needs less oxygen and the breathing rate comes down to
normal in 24 to 48 hours.
- IV fluids
If a baby breathes over 80 times a minute or is working
hard to breathe, he cannot coordinate sucking,
swallowing, and breathing at the same time. The baby is
given fluids through a vein in the hand or foot (an IV)
to prevent dehydration and to keep the blood sugar
levels normal. As soon as the breathing rate is normal,
the baby will be allowed to nurse.
- IV antibiotics
Every newborn with breathing problems is suspected of
having an infection because the difference between
pneumonia and TTN cannot be detected in the early
stages. For this reason the baby is given intravenous
(IV) antibiotics after blood has been drawn for tests.
The medication is continued until the results of the
blood tests confirm that there is no infection. This
usually takes 48 to 72 hours.
OUTCOME
Babies who have TTN recover completely within 24 to 72 hours
after birth and have no long-lasting side effects.
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