Transient tachypnea - newborn Health Article

Alternative Names

TTN; Wet lungs - newborns; Retained fetal lung fluid; Transient RDS

Definition

Transient tachypnea is a respiratory disorder usually seen shortly after delivery in full- or near-term babies.

• Transient means it is short-lived (usually less than 24 hours).
• Tachypnea means rapid breathing (most normal newborns take 40-60 breaths per minute).

Causes, incidence, and risk factors

As the baby grows in the womb, the lungs make a special fluid. This fluid fills the developing baby's lungs and helps them grow. When the baby is born at term, chemicals released during labor tell the lungs to stop making this special fluid. The baby's lungs start removing or reabsorbing it.

The first few breaths your baby takes after delivery fill the lungs with air and help to clear most of the remaining lung fluid. Some of the fluid may also clear when the baby's chest is squeezed while passing through the birth canal.

Babies born before 38 weeks gestation may not respond as well to the chemical signals released during labor, and there may be more fluid in the lung at birth.

If you had a cesarean section without being in labor, the chemical signals telling the lung to stop making and start removing lung fluid are not as strong, again leaving more fluid in the lung at the time of birth.

If you have diabetes or received large amounts of pain medications during labor your baby is also at risk of developing TTN.

Symptoms

Newborns with TTN have respiratory problems soon after birth, usually within 1 - 2 hours.

Symptoms include:

• Rapid, noisy breathing, such as grunting
• Flaring nostrils or movements between the ribs or breastbone known as retractions

Signs and tests

The mother’s pregnancy and labor history are important to make the diagnosis.

Tests performed on the baby may include:

• Chest x-ray to rule out other causes of breathing problems
• Blood count and blood culture to try to rule out infection

TTN is usually diagnosed after monitoring your baby for 1-2 days.