Background : Pulmonary function testing is an essential part in assessing patients with lung problems. However, it necessitates corporation and though, it cannot be performed easily in infants. The currently established technique in infants, the Raised-volume rapid thoracoabdominal compression technique (RVTCT), uses a compression vest to squeeze the chest forcely after inflating the lungs. Though commonly used, it is far from perfect since it is not easy to perform. The quality of the data established from the Raised-volume passive expiration technique (RVPE), has hitherto not been investigated.
Aim : To compare data collected from the RVPE flow-volume loops with those of the RVTCT and investigate the ability and ease of creating a technically valid loop.
Methods: A retrospective study investigating the RVPE and the RVTCT loops in infants being tested at Hadassah hospital during the years 2011-2015. Data was gathered for FVC (Forced Vital Capacity), FEV0.5 , FEV0.75 (Forced Expiratory Volume at 0.5 and 0.75 seconds), and the respective parameters on the RVPE loops.
Results : Of 166 tests meeting inclusion criteria, 35% did not have valid RVTCT loops, as opposed to 8.4% of the RVPE group. In 107 tests with valid loops, only a third of the trials ended in a valid RVTCT loop, compared to 70% of RVPE loop trails.
FVC, FEV0.5, FEV0.75 and FEV0.5/FVC were correlated with their perspective parameters on the RVPE loops. R was equal to 0.888, 0.844, 0.819 and 0.646 respectively (P<0.05).
Conclusions: RVPE is easier to perform and is well corellated with the RVTCT.
