The Normal Values of Pulmonary Function Test (PFT) in Neonates according to Postconceptional Age (PCA) and Changes of PFT in Neonatal Respiratory Diseases

Chey, Myoung Jae

Abstract

PURPOSE: Aim of this study is to obtain the normal values of pulmonary function test (PFT) in newborn babies according to their postconceptional age and to detect changes in PFT values of neonatal lung diseases including respiratory distress syndrome and meconium aspiration pneumonia.
METHODS
PFT was performed in 60 newborn babies who were admitted in the neonatal intensive care unit and newborn nurseries of Inje University Sanggye Paik Hospital from 2002. 11. 1. to 2003. 10. 31. The PFT data of 20 respiratory distress syndrome (RDS) and 20 meconium aspiration pneumonia patients during the same period were analyzed and compared with normal values of similar postconceptional age group to find what kind of changes in PFT values occur in patient groups. PFT values including compliance (C), resistance (R), functional residual capacity (FRC), tidal volume (TV), percent volume to peak flow (%V-PF) were measured.
RESULTS
1) In PCA 30-32 week newborns, C:1.22+/-0.43 (mL/cmH2O), R:0.12+/-0.07 (cmH2O/mL/sec), FRC:20.9+/-12.7 (mL/kg), TV:7.1+/-3.6 (mL/kg), In PCA 33-36 week newborns, C:1.81+/-0.76 (mL/cmH2O), R:0.09+/-0.04 (cmH2O/mL/sec), FRC:23.3+/-14.1 (mL/ kg), TV:7.3+/-4.3 (mL/kg). In PCA 37-42 week newborns, C:2.08+/-0.57 (mL/cmH2O), R:0.08+/-0.06 (cmH2O/mL/sec), 28.3+/-13.4 (mL/kg), TV:8.5+/-4.1 (mL/kg). 2) In RDS patients of PCA 30-36 week, C:0.08+/-0.02 (mL/cmH2O), FRC:12.3+/-4.3 (mL/kg), %V-PF:0.27+/-0.11. These values were significantly decreased comparing with normal PFT values of newborns with similar postconceptional age (P<0.05).
CONCLUSIONS
Lung compliance and FRC of normal newborns increased with increase of their postconceptional age. In RDS patients compliance, FRC and %V-PF were significantly decreased comparing with normal newborns with similar postconceptional age.