Lung function in very preterm infants with patent ductus arteriosus under conservative management: an observational study

Table 2 Comparison of pulmonary function parameters in the two groups

	PDA^a	No-PDA	P value
	(n = 28)	(n = 20)	P value
Postnatal age at testing, days	91.8 ± 30.7	69.2 ± 23.1	0.012^b
PMA at testing, weeks	40.4 ± 2.8	38.8 ± 3.0	0.063^b
Body weight at testing, kg	2.71 ± 0.58	2.65 ± 0.59	0.385^b
Body length at testing, cm	46.7 ± 4.9	46.5 ± 4.1	0.690^b
FRC (ml)	57.1 ± 19.5	56.4 ± 19.0	0.580^c
FRC (ml/kg)	21.6 ± 8.4	21.5 ± 6.7	0.894^c
FRC (ml/cm)	1.23 ± 0.44	1.20 ± 0.33	0.866^c
Vt (ml)	23.3 ± 4.9	23.4 ± 4.6	0.430^c
Vt (ml/kg)	8.8 ± 2.4	9.0 ± 1.5	0.432^c
MV (ml/kg/min)	1359.9 ± 693.5	1358.3 ± 536.0	0.778^c
RR (/min)	78.1 ± 20.2	80.2 ± 15.0	0.637^c
T_I (s)	0.39 ± 0.10	0.36 ± 0.08	0.151^c
T_PTEF (s)	0.16 ± 0.06	0.20 ± 0.15	0.390^c
T_PTEF/T_E (%)	41.1 ± 16.4	46.0 ± 18.4	0.759^c
LCI	15.4 ± 4.4	16.2 ± 3.4	0.745^c
M1/M0	5.0 ± 2.2	5.1 ± 1.7	0.529^c
M2/M0	41.1 ± 16.4	46.0 ± 18.4	0.887^c

^aPDA with conservative treatment
^bcompared using the Mann–Whitney U-test
^cP value: after adjustment with GA, and PMA at testing
All continuous data are presented as mean ± SD
FRC functional residual capacity; Vt tidal volume; T_I inspiratory time; T_PTEF time to peak tidal expiratory flow; T_PTEF/T_E the ratio of time to peak tidal expiratory flow over total expiratory time; LCI lung clearance index; M1/M0 and M2/M0, first and second moment ratios

ISSN: 1471-2431