Correlation of pulmonary functional change of tidal respiration with monitoring result of polysomnography in children with obstructive sleep apnea hyperpnea syndrome

Objective To investigate the pulmonary functional change of tidal respiration and its predictive value from the result of polysomnography(PSG) in children with obstructive sleep apnea hyperpnea syndrome(OSAHS).Methods Based on the overnight monitoring result of PSG,68 children with OSAHS were divided into two groups consisting of positive-PSG group(n = 53) and negative-PSG group(n = 15).Parameters of PSG including apnea hyperpnea index(AHI),apnea index(AI),hyperpnea index(HI) and lowest SaO2 were calculated.All patients in the two groups also received daytime testing of pulmonary function of tidal respiration,and the primary parameters were recorded including tidal volume/kg(VT/kg),respiratory rate(RR),inspiratory time(TI),expiratory time(TE),ratio of Ti /Te(TI /TE),peak tidal expiratory flow(PTEF),time to PTEF(TPEF),ratio of TPEF and total TE(TPEF /TE),expiratory volume at PTEF(VPEF),ratio of VPEF and total VE(VPEF /VE),TEF25% remaining,TEF50% remaining,and TEF75% remaining(TEF25%,TEF50%,TEF75%).Results VT /kg were significantly lower while TPEF,TPEF /TE,VPEF,VPEF /VE were obviously higher in positive-PSG group compared to those in negative-PSG group(P 0.01 for all).The changes of parameters in positive-PSG group were improved to different extents after treat-ment.It was analyzed by multiple linear regression that AHI level was correlated with VT /kg,TPEF,TPEF /TE,VPEF and VPEF /VE.However,using matched-pair chi-square test,no significantly statistical difference was found between pulmonary function of tidal respiration and PSG for the assessment of OSAHS.Conclusions It is feasible that pulmonary function of tidal respiration,as a simple and economic method,can serve as one of the important examinations for the diagnosis of childhood OSAHS.In particular it can be used as preliminarily screening before PSG monitoring for predicting a positive outcome.