Thorax: first published as 10.1136/thx.42.2.126 on 1 February 1987. Downloaded from Thorax 1987;42:126-130 Impaired tracheobronchial clearance in bronchiectasis D C CURRIE, D PAVIA, J E AGNEW, M T LOPEZ-VIDRIERO, P D DIAMOND, P J COLE, S W CLARKE From the Host Defence Unit, Department of Thoracic Medicine, Cardiothoracic Institute, Brompton Hospital, and the Royal Free Hospital and School ofMedicine, London ABSTRACT Tracheobronchial clearance was measured by a radioaerosol technique in 12 patients with bronchiectasis, seven patients with chronic obstructive lung disease expectorating mucoid sputum daily (group X), eight patients with chronic obstructive lung disease but negligible sputum expectoration (group Y), and 10 healthy subjects. The patients with bronchiectasis all expectorated purulent sputum daily (mean wet weight 47 g/day), had reduced forced expiratory volume in one second (FEV1) (mean 47 5% predicted), and were unable to avoid coughing during the six hour observation period. None of the patients with bronchiectasis or the healthy subjects were current smokers. There were five current smokers in group X and six in group Y. The mean FEV1 in group X was 41% predicted and in group Y 52% predicted, both values similar to that of the patients with bronchiectasis. Tracheobronchial clearance in the first six hours after inhalation of radioaerosol was significantly (p < 0-01) slower in patients with bronchiectasis than in matched healthy subjects despite more proximal deposition of radioaerosol (p = 0 01) and more coughing (p < 001) in the former. copyright. Tracheobronchial clearance in patients with bronchiectasis was impaired to a similar degree to that in patients with chronic obstructive lung disease but no bronchiectasis. Clearance ofmicrobes and host derived inflammatory group of 12 patients with bronchiectasis and consid- products from the lungs of patients with bronchi- erable airways obstruction and compared these with http://thorax.bmj.com/ ectasis is important if the vicious circle of microbial the deposition and clearance in patients with chronic colonisation and host response that may lead to obstructive lung disease but no bronchiectasis and in progression of lung damage is to be avoided.' healthy subjects. Only one previous study2 has reported impaired lung mucociliary clearance in patients with bronchi- Methods ectasis (these did not have clinical Kartagener's syn- drome but were not tested for a primary ciliary PATIENTS dyskinesia). The clearance rates of inhaled particles in Three groups of patients and one control group were that study were similar to those in patients with studied. on September 28, 2021 by guest. Protected chronic bronchitis. Clearance was impaired in six of Group B-Twelve patients (seven of them men) with the patients with bronchiectasis and mild airways radiologically definite bronchiectasis who were obstruction (mean FEV, 70% predicted) by com- expectorating purulent sputum daily. Seven were ex- parison with that in normal subjects but, surprisingly, smokers and had not smoked for 8-25 years and five in the other eight patients with bronchiectasis, who were lifelong non-smokers. had more severe symptoms and greater airways Group X-Seven men with chronic obstructive lung obstruction (mean FEV1 50% predicted), it was not disease with no evidence of bronchiectasis on plain shown to be significantly impaired. chest radiographs who were expectorating mucoid Because of this discrepancy we measured the lung sputum daily. Five were smokers and two were ex- deposition and clearance on inhaled radioaerosol in a smokers. Group Y-Eight patients (six of them men) with chronic obstructive lung disease but negligible spu- Address for reprint requests: Dr D C Currie, Host Defence Unit, Cardiothoracic Institute, London SW3 6HP. tum expectoration, with no evidence of bronchiectasis on plain chest radiographs. Six were smokers and two Accepted 18 August 1986 ex-smokers. 126 Thorax: first published as 10.1136/thx.42.2.126 on 1 February 1987. Downloaded from Impaired tracheobronchial clearance in bronchiectasis 127 Table I Characteristics ofpatients and controls (meansfor whole groups with standard errors in parentheses) Tobacco 24 h Inspiratory Age Weight Height consunption sputum FEV1 flow rate Group (yr) (kg) (m) (pack y) (g) (% predicted) (Imini') B (Bronchiectasis-n = 12) 55 (3) 70 (4) 1-69 (0-03) 14 (5) 47 (11) 47 (7) 42 (3) X (COLD with sputum-n = 7) 62 (2) 72 (2) 1-67 (0-03) 61 (14)*t 28§ 41 (8)t 40 (3) Y (COLD without sputum-n = 8) 67 (3)*t 66 (3)$ 1-74 (0-04) 56 (13)*t 0-25 52 (8)t 35 (2) Controls (n = 10) 51(5) 74 (4) 1-68 (0-03) 1 0 113 (6)* 40 (5) p < 0-01: significant difference from group B. tp < 0-01, tp < 0-05: significant differences from controls. §Measured in only four patients. COLD-chronic obstructive lung disease. Control group-Ten healthy subjects (five of them assumed to be unavailable for tracheobronchial clear- men) matched with group B for age, sex, height, ance, and were subtracted from the total lung burden weight, and inspiratory flow rate of radioaerosol. to yield the total amount of radioaerosol available for Two were ex-smokers and eight were lifelong non- tracheobronchial clearance. All counts were smokers. expressed as percentages of the initial count to over- come unavoidable differences between subjects in the The characteristics of each group are shown in initial total lung burden of radioaerosol. The remain- table 1. ing amount of radioaerosol available for tracheo- The patients in group B had moderately severe bronchial clearance was measured at regular intervals bronchiectasis as judged by the extent of their disease for the first six hours. The reading at six hours (TBC6) on computed tomography scans3 (median 3 lobes), 24 was used as a measure of this clearance. These data hour sputum production (range 20-120g) and were also displayed graphically and a second measure reduced FEV1 (range 17-91% predicted).4 The of total clearance of radioaerosol was obtained by copyright. median duration of daily sputum production was 45 calculating the area under the curve (AUC), with the years (range 10->60). Haemophilus influenzae was use of the trapezoidal rule, for the six hours. The isolated from the sputum in 11 of the patients, Pseu- lower the value of TBC6 or AUC the greater the tra- domonas aeruginosa in three patients, and Staphy- cheobronchial clearance (for example, with no clear- lococcus aureus in one patient. One patient had ance TBC6 = 100, AUC = 600). http://thorax.bmj.com/ associated rheumatoid arthritis, two had azoospermia Informed written consent was obtained from all the and 10 reported nasal symptoms. Nasal mucociliary subjects before the test. They were asked to omit all clearance by the saccharin method' was longer than theophylline preparations and oral f#2 agonists for the 60 minutes in three patients and a mean of 28 minutes 12 hours before the test. The initial lung burden per in the remainder. The three patients with prolonged study amounted to about 30,pCi (1-1 MBq) of 99mTc, clearance all had normal ciliary beat frequencies. resulting in an absorbed radiation dose to the lungs of the order of 12mrem (0-12mSv). The mean inspira- TECHNIQUE tory flow rate for each group of patients was similar A non-invasive radioaerosol technique was used to (table 1). on September 28, 2021 by guest. Protected measure tracheobronchial clearance.6 The subjects The number of coughs, wet weight of sputum inhaled polystyrene particles of 5 gm diameter, expectorated, and amount of radioaerosol in the labelled firmly with technetium-99m (99mTc), accord- expectorated sputum during the six hour test period ing to a standard protocol.7 The radioaerosol initially were measured. The amount of radioaerosol in the deposited in the lungs was measured and its sub- sputum was expressed as a percentage of the initial sequent clearance was monitored by two scintillation radioaerosol available for tracheobronchial clear- counters located opposite each other anterior and ance. The data werenot normally distributed and sta- posterior to the chest. All radiation counts were cor- tistical significance was assessed by the rected for background radiation and physical decay non-parametric Wilcoxon rank sum test for unpaired of the radionuclide. A final count was carried out at data.8 48 hours in 10 of the 12 patients with bronchiectasis and at 24 hours in the remaining subjects. The amount of alveolar deposition was defined as the Results amount of radioactivity remaining at the time of the last count (24 or 48 hours). These particles were The results for the three groups of patients and the Thorax: first published as 10.1136/thx.42.2.126 on 1 February 1987. Downloaded from 128 Currie, Pavia, Agnew, Lopez- Vidriero, Diamond, Cole, Clarke Table 2 Results (means with standard errors in parentheses) AD TBC6 AUC Cough Sputum Sputum Group (%) (%) (% h) (No) (g) (% radioaerosol) B (Bronchiectasis) 24 (5) 39 (6) 333 (36) 36 (10) 16 (4) 33 (7) X (COLD with sputum) 32 (5)§ 34 (5)t 343 (24)$ 30 (9)4 5 (2)t 19 (8)$ Y (COLD without sputum) 30 (6)§ 42 (4)t 383 (13)t 5 (1)* 0* 0* Controls 44 (4)t 11 (2)* 210 (20)t 0* 0* 0* AD- alveolar deposition as percentage of total lung burden; COLD-chronic obstructive lung disease; TBC6-percentage of initial radio- aerosol available or tracheobronchial clearance (TBC) remaining at six hours. During the six hour observation period: AUC-area under TBC curve; Cough-number ofcoughs; Sputum-grams ofsputum. Sputum: % radioaerosol-percentage of the initial radioaerosol available for TBC expectorated in sputum. *P < 0°01, tp = 0-01: significant differences from group B. tp < 0-01, § <005: significant differences from controls. 10 4) c Mean tracheobronchial clearance 40) curves 12 with L. for patients bronchiectasis (group B), seven Cl) patients with chronic obstructive ._n lung disease and daily sputum 0) (group X), eight patients with I- chronic obstructive lung disease co alone (group Y), and 10 healthy C control subjects.