This condition is not an aspiration but is caused by a delay in the clearance of lung fluid which is naturally present in utero. The delayed clearance of fetal fluid in turn a result of an excess of fetal fluid in the newborn, a disturbance in clearing mechanisms or both.
- is a respiratory disorder that occurs in full-term (>= 37 weeks' gestation) or late preterm (34 to 36 weeks' gestation) infants
- the newborn baby has tachypnoea that settles within a few hours of birth
- consists of tachypnoea, defined as respiratory rate above 60/min, that is self-limiting and usually lasts up to a couple of days
- pathophysiology may involve a dysregulation in the change from a secretive to an absorptive function of the lungs
- associated with factors that hasten this transition,such as elective caesarean section and fast delivery
- risk factors include (1,2)
- macrosomia,
- maternal diabetes,
- twin pregnancy,
- family history of asthma
- may be confused with the early stages of other, more significant respiratory conditions such as early-onset pneumonia orrespiratory distress syndrome, and to some extent is a diagnosis of exclusion
Chest radiology may reveal the fluid as streaky shadows out from the mediastinum, cardiomegaly, fluid in the horizontal fissure on the right, and small pleural effusions.
Interventions in the management of transient tachypnoea of the newborn (TTN) (1)
- salbutamol may reduce the duration of tachypnoea slightly
- uncertain as to whether salbutamol reduces the need for mechanical ventilation
- uncertain whether epinephrine, corticosteroids, diuretics, fluid restriction, or non-invasive respiratory support reduces the duration of tachypnoea and the need for mechanical ventilation, due to the extremely limited evidence available
Reference:
- Edwards MO, Kotecha SJ, Kotecha S.Respiratory distress of the term newborn infant. Paediatric Respiratory Reviews 2013;14(1):29-36; quiz 36-7.
- Bruschettini M, Hassan K-O, Romantsik O, Banzi R, Calevo MG, Moresco L. Interventions for the management of transient tachypnoea of the newborn - an overview of systematic reviews. Cochrane Database of Systematic Reviews 2022, Issue 2. Art. No.: CD013563. DOI: 10.1002/14651858.CD013563.pub2