FİKRET KANAT, Hüseyin ÇİÇEK, TURGUT TEKE

Astımda akciğer difüzyon kapasitesinin hava yolu obstrüksiyonu ile ilişkisi

Amaç: Karbon monoksit difüzyon kapasitesinin (DLco) ölçümü, alveole-kapiller membranda gaz değişimi hakkında bilgi veren önemli bir solunum fonksiyon testidir. Çalışmada astımlı hastalarda obstrüksiyon derecesiyle DLco arasındaki ilişki araştırılmaktadır. Yöntem: Çalışmaya önceden astım tanısı almış ve DLco’yu etkileyecek ilave bir hastalığı olmayan ve sigara içmeyen 91 (ortalama yaş: 37.2±9.4, 18-56 yaş) ve kontrol grubu olarak gönüllü 47 (ortalama yaş: 38.0±8.7, 22-56 yaş) kişi katıldı. Tüm olguların akım hızları, akciğer volümleri ve DLco ölçümleri Vmax22 spirometre cihazı ile yapıldı. Hastalar Global Initiative for Asthma (GINA) rehberinde tanımlanan FEV1 ve PEF parametreleri kullanılarak obstrüksiyon derecesine göre 3 gruba ayrıldı. Buna göre; FEV1 ve PEF değeri ≥ % 80 olan hastalar Grup 1’e (n:25), FEV1 veya PEF değeri ≥ % 80 olup FEV1 veya PEF değerinin herhangi biri % 60-80 arasında olanlar Grup 2’ye (n:29) ve FEV1 veya PEF değerinin herhangi biri ≤ % 60 olan hastalar Grup 3’e (n:37) dahil edildi. Bulgular: Astımlı hastalarla kontrol grubu arasında DLco, DLco (%), alveoler volüm (VA) ve DLco/VA değerleri bakımından istatistiksel olarak anlamlı bir farklılık bulunmadı. Sonuç: Astımlılarda DLco obstrüksiyon derecesinden etkilenmemektedir Bu da astımda efektif VA azalmamasına bağlıdır. DLco ölçümü kronik hava yolu obstrüksiyonu olan hastalarda astımın özellikle amfizemden ayrımında önemli bir yere sahiptir.

Relationship of lung diffusion capacity with airway obstruction in asthma

Objective: The carbon monoxide diffusion capacity (DLco) measurement is an important pulmonary function test, giving information about gas exchange through the alveolocapillary membrane. In this study, the relationship between DLco and the degree of bronchial obstruction in patients with asthma has been investigated. Methods: The study included 91 nonsmoker subjects (mean age: 37.2±9.4, range: 18-56 years) who were previously diagnosed as asthma and not having any diseases affecting DLco, and 47 nonsmoker voluntary subjects (mean age: 38.0±8.7, range: 22-56 years) as controls. Flow rates, lung volumes and DLco measurements of all subjects were performed via Vmax22 spirometer. The patients were subdivided into 3 groups according to the degree of bronchial obstruction, using the parameters of FEV1 and PEF defined in Global Initiative for Asthma (GINA) guideline. Patients who had FEV1 and PEF values ≥ 80 % were included into group 1 (n:25); FEV1 or PEF values ≥ 80 % and any one of FEV1 or PEF values between 60 and 80 % into group 2 (n:29); and any one of FEV1 or PEF values ≤ 60 % into group 3 (n:37). Results: There was not a statistically significant difference between patients with asthma and controls regarding to DLco, DLco (%), VA and DLco/VA values. Conclusion: DLco is not affected by the degree of bronchial obstruction in asthma. This is related to that the effective alveolar volume is not reduced in asthma. DLco measurement has an important role in differentiation of asthma, especially from emphysema.

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