This article requires a subscription to view the full text. If you have a subscription you may use the login form below to view the article. Access to this article can also be purchased.
- Lokesh Guglani, MD*
- Satyan Lakshminrusimha, MD*
- Rita M. Ryan, MD*
- *Department of Pediatrics, University at Buffalo, Women and Children's Hospital of Buffalo, Buffalo, NY
Introduction
The birth of a child is preceded by several changes to prepare for the transition from intrauterine to extrauterine life. The five major events that establish the lungs as the organ of gas exchange at birth include: clearance of fetal lung fluid, establishment of spontaneous breathing, decrease in pulmonary vascular resistance, release of surfactant, and cessation of the right-to-left shunting of venous blood returning to the heart. (1) During fetal life, fluid is secreted into the alveoli to maintain normal growth and function, (2) and fetal lung volume approximates the functional residual capacity that would be established once air breathing is initiated. (3) Clearance of lung fluid can be affected by several factors, and its impairment culminates in tachypnea and could necessitate transfer to an intensive care unit for monitoring and respiratory support.
Transient tachypnea of the newborn (TTN), which is believed to result from incomplete resorption of fluid from the lungs of the newborn, presents an important diagnostic and therapeutic dilemma in the newborn nursery. This review focuses on TTN, with emphasis on fetal lung fluid mechanics and possible mechanisms of fetal lung fluid resorption as well as its pathophysiology, clinical and diagnostic features, and management. Some neonatologists refer to TTN as retained fetal lung liquid syndrome.
Physiology of Fetal Lung Fluid
The lungs are filled with liquid in utero, which increases from 4 to 6 mL/kg body weight at mid-gestation to about 30 to 50 mL/kg near term in fetal lambs. (4) Jost and Policard (5) first demonstrated that fluid within the fetal lung arises from the lung and contributes to the volume of amniotic fluid. The rate of production ranges from 2 mL/kg per hour in the initial part of pregnancy to 5 mL/kg per hour at term, thereby contributing one third to one half of the daily turnover of amniotic fluid. …
Individual Login
Institutional Login
You may be able to gain access using your login credentials for your institution. Contact your librarian or administrator if you do not have a username and password.
Log in through your institution
Pay Per Article - You may access this article (from the computer you are currently using) for 2 days for US$25.00
Regain Access - You can regain access to a recent Pay per Article purchase if your access period has not yet expired.