Am. J. Respir. Crit. Care Med., Vol 152, No. 4, 10 1995, 1284-1289.
Factors limiting exercise performance in long-term survivors of bronchopulmonary dysplasia
P Santuz, E Baraldi, P Zaramella, M Filippone and F Zacchello
Department of Pediatrics, University of Padova School of Medicine, Italy.
The long-term impairment of pulmonary function during exercise was assessed
in 12 children, aged 6 to 12 yr, who developed BPD after prematurity
(gestational age 30 +/- 2 wk [mean +/- SD] and birth weight 1,400 +/- 335
g) and 16 age-, sex-, and physical activity-matched healthy children born
at term, who served as controls. The children performed pulmonary function
tests at rest and a maximal stepwise exercise on a treadmill. Oxygen
consumption (VO2), carbon dioxide output (VCO2), and minute ventilation
(VE) were monitored during the run. Baseline mean spirometric values (% of
predicted) were in the normal range for both groups but were lower in BPD
children with respect to control children (p < 0.05). At rest, arterial
oxygen saturation (SaO2) was > or = 98% in all BPD children, but at peak
exercise, 4 of them had a SaO2 fall > or = 4%. The postexercise FEV1
fall, with respect to the baseline, was 8 +/- 6%, in BPD and 2 +/- 1% in
control children (p < 0.01). Maximum VO2 and VE were significantly lower
in BPD children with respect to the control group (25.2 +/- 10.3 versus
37.1 +/- 10.4 ml/min/kg and 20.8 +/- 9.4 versus 30.7 +/- 7.9 L/min,
respectively, both p < 0.01). Also, at submaximal levels of exercise
dynamic, VO2 and VE responses were significantly lower in the BPD group
(ANOVA, p < 0.001), with a ventilatory pattern characterized by lower
tidal volumes. Anaerobic threshold was 20.6 +/- 9 in BPD and 28.8 +/- 8.6
ml O2/min/kg in healthy children (p < 0.05).(ABSTRACT TRUNCATED AT 250
WORDS)
