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Pulmonary function changes following surgical correction for pectus excavatum.

OBJECTIVE
To assess whether and to what extent pulmonary function returns to normal after surgical correction for pectus excavatum.


METHODS
Twenty-seven patients who could be examined in person at the outpatient department of our hospital were included in this study. Of these patients, 24 were boys and 3 were girls, with age ranging from 3 to 16 years (mean: 8.67 years). The mean age at surgery was 4 years and mean years at follow-up was 6.8. Pulmonary function measurements included inspiratory vital capacity (IVC), total lung capacity (TLC), residual volume (RV), functional residual capacity (FRC), RV/TLC ratio, maximal voluntary ventilation (MVV), forced ventilatory capacity (FVC), forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMEF), maximal expiratory flow at 75% vital capacity (V75), maximal expiratory flow at 50% vital capacity (V50), maximal expiratory flow at 25% vital capacity (V25) and breathing reserve ratio (BR).


RESULTS
TLC, FRC, MVV, MMEF, V75 and V50 were not different from normal values. IVC, FVC, FEV1 and V25 were significantly decreased compared with normal values. RV and RV/TLC were high in 87.5% cases.


CONCLUSIONS
Preoperative symptoms improved substantially after operation. Little airway obstruction was observed postoperatively, suggesting that patients with pectus excavatum should have surgery as early in life as possible, preferably by age 3.