Determinación de volúmenes pulmonares mediante pletismografía en pacientes con fíbrosis quística

Abstract

Introduction: Cystic fibrosis (CF) patients develop a progressive impairment of pulmonary function tests (PFT) by recurrent infection. Objective: To evaluate PFT in CF patients using spirometry, oxygen saturometry (Sa0(2)) and whole plethysmography (WP) for determining possible mathematical relationships. Methods: FVC, FRC, RV, TLC, FEV1, FEF25.75, obtained in 10 CF patients were compared with Zapletal's reference values and with the values obtained in 33 healthy-school children. Results: Mean age 13.6 years-old (range: 9-20). All CF patients had normal Sa0(2), FEV1 was normal in five (four had FEV1 between 65-80%), 4 had RV/TLC > 30%, 3 had increased FRC and RV/TLC, only one CF patient had WP normal. The average of TLC and RV were higher than reference values and control group (p < 0.05). We found an inverse relationship between FEV1, FEF25-75 and RV/TLC [r = -0.642 (p < 0.05) and r = -0.803 (p < 0.01); respectively]. Conclusion: This study suggests an increase of pulmonary volume in CF patients with not necessarily abnormal spirometry and an inverse mathematical relationship between FEV1, FEF25-75 and RV/TLC.