Crying vital capacity. Measurement of neonatal lung function

Area of Science:

• Neonatal Physiology
• Pulmonary Function Testing
• Pediatric Respiratory Medicine

Background:

• Neonatal respiratory function is crucial for infant health.
• Assessing pulmonary function in newborns requires non-invasive methods.
• Crying vital capacity (CVC) is a potential indicator of lung function.

Purpose of the Study:

• To evaluate crying vital capacity (CVC) in neonates.
• To compare CVC in infants based on birth mode (vaginal vs. cesarean) and gestational age.
• To assess CVC in infants with respiratory conditions like hyaline membrane disease (HMD) and transient tachypnea (TT).

Main Methods:

• Serial measurements of CVC using reverse plethysmography.
• CVC expressed as ml/cm chest circumference.
• Measurements taken during the first two weeks of life.

Main Results:

• Term infants born via elective cesarean section showed lower mean CVC compared to vaginally born infants.
• No significant CVC difference was observed between vaginal and urgent cesarean births.
• Infants born via cesarean section exhibited a smaller percentage rise in CVC within 24 hours and a delayed rise between 24-48 hours.
• Preterm infants had lower CVC than term infants but showed a significant rise between 5-10 days.
• Infants with HMD had lower CVC than preterm infants, and those with TT had lower CVC than term infants.
• CVC decreased in infants with HMD between 24-48 hours, while it increased in infants with TT during the same period.

Conclusions:

• Crying vital capacity (CVC) is a valuable, non-invasive tool for assessing neonatal lung function.
• Birth mode, particularly elective cesarean section, affects early CVC development.
• CVC patterns can help differentiate between respiratory conditions like HMD and TT in neonates.
• CVC aids in evaluating neonates with respiratory distress.