Life Science Encyclopedia

Transient tachypnea of the newborn (TTNB, or "Transitory tachypnea of newborn") is a respiratory problem seen in the newborn shortly after delivery. It consists of a period of rapid breathing (more than the for newborns normal 40-60 times a minute). It is likely due to retained lung fluid, and common in 35+ week gestation babies who are delivered by caesarian section without labour. Usually, this condition resolves over 24-48 hours. Treatment is supportive and may include supplemental oxygen and antibiotics. The chest X-Ray shows hyperinflation of the lungs including prominent pulmonary vasular markings, flattening of the diaphragm, and fluid in the horizontal fissure.

Pathophysiology

• 1. Due to the higher incidence of TTN in newborns delivered by caesarean section, it has been postulated that TTN could result from a delayed absorption of fetal lung fluid from the pulmonary lymphatic system. The increased fluid in the lungs leads to increased airway resistance and reduced lung compliance.

• 2. Pulmonary immaturity has also been proposed as a causative factor. Levels of phosphatidylglycerol (an indicator of lung maturity) was found to be negative in certain newborns.

• 3. Mild surfactant deficiency has also been suggested as a causative factor.