Transient tachypnea of the newborn is a

respiratory The respiratory system (also respiratory apparatus, ventilatory system) is a biological system consisting of specific organs and structures used for gas exchange in animals and plants. The anatomy and physiology that make this happen varies gre ...

problem that can be seen in the

newborn An infant or baby is the very young offspring of human beings. ''Infant'' (from the Latin word ''infans'', meaning 'unable to speak' or 'speechless') is a formal or specialised synonym for the common term ''baby''. The terms may also be used to ...

shortly after delivery. It is caused by retained fetal lung fluid due to impaired clearance mechanisms. It is the most common cause of respiratory distress in term neonates. It consists of a period of

tachypnea Tachypnea, also spelt tachypnoea, is a respiratory rate greater than normal, resulting in abnormally rapid and shallow breathing. In adult humans at rest, any respiratory rate of 1220 per minute is considered clinically normal, with tachypnea b ...

(rapid breathing (higher than the normal range of 30-60 times per minute). Usually, this condition resolves over 24–72 hours. Treatment is supportive and may include supplemental

oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements ...

and

antibiotic An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention ...

s. The chest

x-ray An X-ray, or, much less commonly, X-radiation, is a penetrating form of high-energy electromagnetic radiation. Most X-rays have a wavelength ranging from 10 picometers to 10 nanometers, corresponding to frequencies in the range 30&nb ...

shows hyperinflation of the lungs including prominent pulmonary vascular markings, flattening of the

diaphragm Diaphragm may refer to: Anatomy * Thoracic diaphragm, a thin sheet of muscle between the thorax and the abdomen * Pelvic diaphragm or pelvic floor, a pelvic structure * Urogenital diaphragm or triangular ligament, a pelvic structure Other * Diap ...

, and fluid in the horizontal fissure of the right lung.

Signs and symptoms

Symptoms of transient tachypnea of the newborn include

respiratory distress Shortness of breath (SOB), also medically known as dyspnea (in AmE) or dyspnoea (in BrE), is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing disc ...

and rapid breathing (

). This condition usually occurs within the first two hours of birth in full term and late term newborn infants.

Pathophysiology

Due to the higher incidence of transient tachypnea of the newborn in infants delivered by caesarean section, it has been postulated that it 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. It is thought this could be from lower levels of circulating

catecholamine A catecholamine (; abbreviated CA) is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine. Catechol can be either a free molecule or a su ...

s after a caesarean section, which are believed to be necessary to alter the function of the ENaC channel to absorb excess fluid from the lungs. Pulmonary immaturity has also been proposed as a causative factor. Levels of phosphatidylglycerol (an indicator of lung maturity) were found to be negative in certain newborns Mild surfactant deficiency has also been suggested as a causative factor.

Diagnosis

Transient tachypnea of the newborn is a diagnosis of exclusion as it is a benign condition that can have symptoms and signs similar to more serious conditions, such as respiratory distress syndrome. A chest X-ray may show a radiopaque line - fluid - in the horizontal fissure of the right lung, fluid infiltrate throughout alveoli or fluid in individual lung lobes. The lungs may also appear hyperinflated.

Treatment

Supportive care is the treatment of choice for transient tachypnea of the newborn. This may include withholding oral feeding in periods of extreme tachypnea (over 60 breaths per minute) to prevent aspiration, supplemental oxygen, and CPAP. Evidence from clinical trials investigating the use of postnatal

corticosteroids Corticosteroids are a class of steroid hormones that are produced in the adrenal cortex of vertebrates, as well as the synthetic analogues of these hormones. Two main classes of corticosteroids, glucocorticoids and mineralocorticoids, are invol ...

for transient tachypnea of the newborn is inconclusive. Similarly, the clinical trial evidence investigating non-invasive respiratory support (i.e. without endotracheal intubation) compared to supplemental oxygen is uncertain.

Epinephrine Adrenaline, also known as epinephrine, is a hormone and medication which is involved in regulating visceral functions (e.g., respiration). It appears as a white microcrystalline granule. Adrenaline is normally produced by the adrenal glands and ...

salbutamol Salbutamol, also known as albuterol and sold under the brand name Ventolin among others, is a medication that opens up the medium and large airways in the lungs. It is a short-acting β2 adrenergic receptor agonist which works by causing rel ...

( albuterol) have been suggested as a treatment option for transient tachypnea, as a result of evidence that β-agonists increase the speed of alveolar fluid clearance in the lung of newborns. However, the safety and effectiveness of these treatment approaches is not clear.

Prognosis

Transient tachypnea of the newborn is usually self limiting, however, it may be associated with

wheezing A wheeze is a continuous, coarse, whistling sound produced in the respiratory airways during breathing. For wheezes to occur, some part of the respiratory tree must be narrowed or obstructed (for example narrowing of the lower respiratory tract ...

syndromes as the child grows older.

Epidemiology

Transient tachypnea of the newborn occurs in approximately 1 in 100 preterm infants and 3.6-5.7 per 1000 term infants. It is most common in infants born by Caesarian section without a trial of labor after 35 weeks' gestation. Male infants and infants with an

umbilical cord prolapse Umbilical cord prolapse is when the umbilical cord comes out of the uterus with or before the presenting part of the baby. The concern with cord prolapse is that pressure on the cord from the baby will compromise blood flow to the baby. It usuall ...

or perinatal asphyxia are at higher risk. Parental risk factors include use of pain control or anesthesia during labor,

asthma Asthma is a long-term inflammatory disease of the airways of the lungs. It is characterized by variable and recurring symptoms, reversible airflow obstruction, and easily triggered bronchospasms. Symptoms include episodes of wheezing, co ...

, and

diabetes Diabetes, also known as diabetes mellitus, is a group of metabolic disorders characterized by a high blood sugar level ( hyperglycemia) over a prolonged period of time. Symptoms often include frequent urination, increased thirst and increased ...

References

External links

{{Certain conditions originating in the perinatal period Respiratory and cardiovascular disorders specific to the perinatal period Neonatology