LONG-TERM PULMONARY SEQUELAE OF SEVERE BRONCHOPULMONARY DYSPLASIA

Objective: To evaluate the long-term pulmonary sequelae of survivors o f bronchopulmonary dysplasia (BPD) of sufficient severity to have requ ired supplemental oxygen for at least 1 month after term. Study design : Fifteen patients with a mean age of 1.1 years were matched to preter m infants of similar gestational age and age at time of study. Pulmona ry function testing included spirometry, plethysmographic lung volumes , carbon monoxide diffusion capacity, and in 9 of 15 subjects with BPD , measurement of lung static elastic recoil pressures. Results: The su bjects with BPD had a mean expiratory volume in 1 second (FEV1) of 64% +/- 21% predicted (4 had an FEV1 < 50% predicted) compared with 85% /- 11% (P < .01) for the preterm children in the control group. Subjec ts with BPD had a significant degree of gas trapping with a residual v olume to total lung capacity ratio of 37% +/- 13% compared with 25% +/ - 4% for the control group (P < .01). An inverse relationship was seen between the FEV1 and the time on supplemental oxygen (r = -0.84, P < .0001), with 3 of the 4 children whose FEV1 was < 50% requiring oxygen for more than 900 days. Those with the greatest degree of airflow lim itation and gas trapping had the greatest abnormalities in both shape and position of the pressure volume curves of the lung. Conclusion: Se vere BPD may result in moderate to severe long-term abnormalities in p ulmonary function tests.