Comparison of Single Breath Carbon Monoxide Diffusing Capacity and Pressure-Volume Curves in Detecting Emphysema

Abstract

To evaluate the sensitivity of diffusing capacity (DLCO) and pressure-volume (P-V) curves in the detection of emphysema, these tests were compared with pathologic assessment of emphysema in patients undergoing lung resection for a localized tumor, and with the overall extent of emphysema as assessed by computed tomography (CT). The resected lung specimens were fixed in the inflated state and cut at 1-cm intervals in the horizontal plane. The pathologic extent of emphysema was quantitated by comparison with a standard reference panel of emphysema grading. The overall extent of emphysema on CT was assessed by a visual scoring system in a total of 55 patients, 19 undergoing lung resection and 36 not undergoing lung resection. Analysis of 37 patients by pathology scores revealed 18 with no or trivial emphysema (emphysema grades less than or equal to 5; mean grade, 2.2 +/- SD 2.6) and 19 with emphysema (grades greater than or equal to 10; mean grade, 33.2 +/- SD 24.2). Diffusing capacity, the ratio of DLCO to alveolar volume (DLCO/VA), maximal lung elastic recoil (PLmax), and lung elastic recoil at 90% of total lung capacity (PL90) were significantly different between the two groups, whereas K (the exponential constant describing the shape of the P-V curve) was not. The pathology grade of emphysema showed a significant correlation with (DLCO) (r = -0.53) and DLCO/VA (r = -0.55), which was greater than the correlation with PLmax (r = -0.42) and PL90 (r = -0.43).(ABSTRACT TRUNCATED AT 250 WORDS)

Tumour necrosis factor family genes in a phenotype of COPD associated with emphysema

“…The first group of subjects consisted of 63 consecutive male patients with history of COPD, diagnosed according to the American Thoracic Society (ATS) guidelines [22] and characterised by significant impairment in diffusing capacity for carbon monoxide (DL,CO), a functional abnormality known to be associated with pulmonary emphysema [23,24]. These patients were recruited in two clinical centres, 33 in Pavia and 30 in Gussago, both located in Northern Italy, based on a common protocol requiring forced expiratory volume in one second (FEV1) v50% pred, v12% reversible, FEV1/forced vital capacity (FVC)v70% pred, and DL,COv50% pred.…”

“…The mean¡SD FEV1 reversibility in these subjects was 4¡4. The low level of DL,CO in the COPD group (37¡12% pred) allowed them to be defined as affected by moderate-to-severe COPD (Stage II-III) associated with pulmonary emphysema [23,24].…”

Severe airflow obstruction in a patient with ulcerative colitis and toxic epidermal necrolysis: A case report

“…Early-onset chronic obstructive pulmonary disease was initially suspected from the patient's symptoms and severe irreversible airway limitation; however, the chest CT scan was not consistent with smoking-induced centrilobular emphysema in this case, although the diagnosis of panlobular emphysema could not be refuted. It is generally accepted that decreases in DL CO and DL CO /VA are useful indicators of pulmonary emphysema (19,20); therefore, these parameters were evaluated, but no decreases were found despite severe irreversible airflow limitation. A mosaic pattern and bronchiectasis have been reported to be the typical findings in OB, although there have been cases demonstrating only diffuse hyperinflation, bronchial wall thickening and bronchiectasis, or even normal findings on a CT scan (21,22).…”

Kroni̇k Obstrükti̇f Akci̇ğer Hastaliklarinda Di̇ffüzyon Kapasi̇tesi̇ni̇n Spesi̇fi̇k Di̇ffüzyon Katsayisinin Önemi̇

“…Amfizem tanısı, The Intermountain Thoracic Society'ye göre; havayolu obstrüksiyonu, akciğerin fazla havalanması, DLCO"'da azalma ile desteklenebilecğini bildirirken (6), Morrison ve ark. amfizemde 2 önemli fonksiyon bozukluğundan birinin DLCO'nun azalması (diğerinin akciğer elastisitesindeki azalma) olduğu-nu ifade etmişlerdir (13). Amfizemde DLCO; alveolokapiller membran yüzey alanının azalması, kapiller yatağın azalması, terminal bronşiol ve alveolokapiller membran arası mesafenin artması, V/P dengesindeki bozukluklar nedeni ile azalmaktadır (6,7,10,14,18,23).…”