FRC
Also written as: FRC — Functional Residual Capacity
Functional residual capacity - the volume of air remaining in the lungs after normal expiration.
Full Definition
FRC, or functional residual capacity, represents the volume of air that remains in the lungs at the end of passive expiration when the elastic recoil of the lungs is balanced by the chest wall's outward recoil. In neonates, particularly preterm infants, FRC is often reduced due to immature lung development, surfactant deficiency, and compliant chest walls. Maintaining adequate FRC is crucial for proper gas exchange and preventing atelectasis. Respiratory support strategies like CPAP and PEEP help preserve FRC by providing continuous positive pressure that prevents alveolar collapse. Measurement of FRC in neonates can be challenging and typically requires specialized equipment such as helium dilution or nitrogen washout techniques. Changes in FRC can indicate improvement or deterioration in respiratory status.
Usage
Usage note: Essential concept in understanding neonatal respiratory physiology and ventilator management.
In Context
- "The preterm infant's reduced FRC contributed to persistent atelectasis and poor oxygenation." — Pulmonology consultation
- "CPAP therapy helped maintain FRC and reduced the work of breathing in this RDS patient." — Respiratory therapy note