Is Cough As Effective As Chest Physiotherapy in the Removal of Excessive Tracheobronchial Secretions?

Thorax: first published as 10.1136/thx.36.9.683 on 1 September 1981. Downloaded from

Thorax 1981;36:683-687

Is cough as effective as chest physiotherapy in the removal of excessive tracheobronchial secretions?

JRM BATEMAN, SP NEWMAN, KATHLEEN M DAUNT, NOIRIN F SHEAHAN, D PAVIA, SW CLARKE From the Departments of Thoracic Medicine, Medical Physics, and Physiotherapy, The Royal Free Hospital, London

ABSTRACT The relative value of chest physiotherapy (including cough) and cough alone for the removal of excessive tracheobronchial secretions has been assessed in six patients with stable chronic obstructive lung disease. After labelling with inhaled radioactive tracer particles, clearance of secretions from selected central and peripheral lung regions was followed with a gamma camera linked to a computer. Cough alone and chest physiotherapy (including cough) were equally effective in the enhancement of central lung clearance. Physiotherapy but not cough alone accelerated peripheral lung clearance (p < 0 05). Sputum yield was greater during physiotherapy than during cough (p < 0-05). These findings confirm the value of chest physiotherapy and high-light the limitation of cough in patients with excessive tracheobronchial secretion and impaired mucociliary clearance. copyright. Since the description of simple manoeuvres in 1915,1 bronchiectasis. Three were non-smokers, two ex- chest physiotherapy has become established in the smokers, and one a current smoker. Their physical treatment of chronic lung conditions associated characteristics and ventilatory function are sum- with excessive tracheobronchial secretions. Objec- marised in table 1. tive evidence for its value, however, is both lacking The labelling of tracheobronchial secretions by an and controversial.2 3 Using the radioaerosol tracer aerosol containing uniform 5 ,um polystyrene http://thorax.bmj.com/ technique,4 we were able to establish the efficacy particles firmly tagged with 99mTc (half-life 6 h) of the various combined manoeuvres of the chest has been fully described previously.6 After the physiotherapist with cough in aiding the removal controlled inhalation of radioaerosol, the clearance of excessive secretions from central, intermediate of particles deposited throughout the tracheo- and peripheral lung regions. Oldenburg et al,5 bronchial tree was monitored by external gamma however, using similar techniques subsequently counting using a Nuclear Enterprises Mark III produced data suggesting that cough alone was as gamma camera. Counts were collected from the effective as chest physiotherapy combined with anterior chest over five-minute periods at half- on September 24, 2021 by guest. Protected cough. We have therefore examined critically the hourly intervals from 30 to 150 minutes after relative roles of cough alone and chest physiotherapy with cough in enhancing regional lung clearance. Table 1 Physical characteristics, daily sputum production, and ventilatory function for six patients Methods with stable chronic airways obstruction Six patients (three men and three women) with stable Characteristic Results (mean SD) chronic airway obstruction and regular daily Age (yr) 60 ± 16 Height (m) 1-63 0 09 expectoration took part in the study. Written Weight (kg) 61 : 10 informed consent from the patients and approval Sputum production (ml/day) 160 ± 100 of the local ethics committee were obtained. Three PEFR observed (1/min) 166 i 38 PEFR % predicted 38 ± 6 patients had chronic obstructive bronchitis and three FEV1 observed (1) 0 94 0 43 FEV1 % predicted 37 + 13 Address for reprint requests: Dr D Pavia, Department FVC observed (1) 1-75 0 64 FVC V. predicted 55 i 16 of Thoracic Medicine, The Royal Free Hospital, London + NW3 2QG. FEVJ/FVC observed (%) 52 6 683 Thorax: first published as 10.1136/thx.36.9.683 on 1 September 1981. Downloaded from

684 Bateman, Newman, Daunt, Sheahan, Pavia, Clarke radioaerosol inhalation. A P-D-P 1105 computer cough was preceded by a deep inspiration of air. All enabled the calculation of particle clearance from manoeuvres were given by hand which was held in selected central, intermediate and peripheral lung the cupped position during percussion. The fre- regions (fig 1). quency of each manoeuvre was determined by the For each region the data from both lungs were physiotherapist applying her techniques to a large combined. All counts were corrected for radio- ambu bag filled with air and attached to a pressure active decay and background. Clearance was ex- transducer (SE Laboratories type 1150) linked with pressed as a percentage of the initial radioactivity an ultraviolet recorder (SE Laboratories oscillograph counts to compensate for unavoidable differences type 3006) via an amplifier and pre-amplifier (SE in radioactive lung burden between patients and Laboratories types 4910 and 4919). Frequency was studies. A radiation dose of less than 15 mrem was thus measured from a trace of pressure against time. delivered to the lungs during each inhalation During the equivalent period in the third study, the procedure. patients were instructed by the physiotherapist to Each patient completed a control, a chest physio- cough for one-minute periods every five minutes. therapy, and a cough study in a random order The total period of coughing was the same for both separated by one or two days. All bronchodilator the physiotherapy andthecoughstudies. Spontaneous therapy was withdrawn for 12 h and simple venti- coughing was allowed in all three studies one and latory function assessed 1 h before each study. In a half hours after radioaerosol inhalation. All all three studies the patients refrained from coughing sputum samples produced during the physiotherapy for the first 60 minutes and, in the control study, for and cough periods were collected and weighed. the first 90 minutes after radioaerosol inhalation. In As the number of patients studied was small and the physiotherapy study a sequence of postural the results do not follow a normal distribution. drainage, vibration (12 to 16 Hz), shaking (2 Hz), non-parametric methods have been used in the and percussion (5 Hz) was administered for four statistical analysis.7 minutes every five minutes for a total duration of

20 minutes one hour after the inhalation of radio- Results copyright. aerosol. The patient lay horizontally in the left and right lateral positions for equal periods of time. Ventilatory function was similar for all three study At the end of each four-minute sequence the patient days, confirming the stability of airway obstruction. was sat upright and was instructed by the physio- The initial group mean distribution of radioaerosol therapist to cough for a one minute period. Each across the three selected lung regions was also

similar (fig 2). The group mean retention of deposited http://thorax.bmj.com/

50r n CONTROL

0T PHYSIOTHERAPY on September 24, 2021 by guest. Protected

Fig 2 Initial group (six patients) mean distribution of deposited radioaerosol 30 min after particle inhalation Fig 1 The computer-selected lung regions: central (C), across the three selected regions. The results from right intermediate (I), andperipheral (P), related by area in and left lungs have been combined and expressed as a the ratio 2:1:2. percentage of the combined total lung count. Thorax: first published as 10.1136/thx.36.9.683 on 1 September 1981. Downloaded from

Is cough as effective as chest physiotherapy in the removal ofexcessive tracheobronchial secretions ? 685 radioaerosol for the three selected regions and the Discussion total lung fields is shown in fig 3. All the curves from 30 to 60 minutes are similar. After chest physio- Lung mucociliary clearance has been found to be therapy there was a marked fall in deposited radio- impaired in chronic bronchitis,8 bronchiectasis,9 aerosol in all regions and in the total lung fields. and cystic fibrosis,10 leading to an excess of tracheo- The fall after cough alone was similar to that bronchial secretions partly cleared by cough, a major following physiotherapy in the central lung region symptom. Chest percussion, shaking, vibration, and but less in the intermediate region and total lung postural drainage are manoeuvres used by the physio- fields. In the peripheral lung region, however, the therapist to move tenacious peripheral bronchial fall after cough alone was similar to that during the secretions to more central airways for expectoration equivalent control period. by coughing. In the present study, chest physio- The group mean clearance of deposited radio- therapy with cough accelerated both central and aerosol for each region and the total lung fields peripheral lung clearance, whereas cough alone during the physiotherapy, cough, and respective enhanced central lung clearance but was ineffective control periods is shown in table 2. For the total in peripheral lung regions and, furthermore, yielded lung fields and central and intermediate regions, less sputum. These findings confirm that cough only clearance was signficantly more (p < 0-05) for partially compensates for impaired mucociliary both physiotherapy and cough studies than for the clearance and that chest physiotherapy is a necessary respective control period. Only chest physiotherapy adjunct for the enhancement of impaired peripheral produced a significant increase in peripheral lung lung clearance. clearance (p < 0 05). The essential component of the cough mechanism No sputum samples were produced during the is the generation of a linear velocity of air flow first 90 minutes of the control study. The group within a given airway high enough to shear secretions mean weight of sputum collected during physio- from its walls.'1 The relevant linear flow is the post- therapy was significantly more than that during the peak sustained flow'2 and approximates to half the cough study (physiotherapy 19 ± 5 (SE)g; cough PEFR.13 In the chronic bronchitic, the PEFR may copyright. alone 11 ± 3 (SE)g; p < 0*05). be very low and the post-peak flow even lower

TOTAL LUNG FIELDS CENTRAL LUNG INTERMEDIATE LUNG PERIPHERAL LUNG REGION REGION REGION 100 http://thorax.bmj.com/ 90 Fig 3 The group (six patients) mean retention of 80 deposited radioaerosolfor 70 T E~~~~ the three selected regions L-1, z and total lung fields. The 60- results from right and left so lungs have been combined and expressed as a percentage ofthe count at 30 min post particle on September 24, 2021 by guest. Protected 0 . , ,.I I e I 30 60 90 120 150 30 60 90 120 150 30 60 90 120 150 30 60 90 120 150 inhalation. TIME (MIN ) 0-0 CONTROL *-* CHEST PHYSIOTHERAPY AA COUGH

Table 2 Group mean (± SE) clearance ofdeposited radioaerosol (six patients) expressed as a percentage ofeach regional lung count 30 min after particle inhalation during chest physiotherapy, cough, and equivalent control periods. *Statistical differences from control period p < 0 05 Total lung fields Central lung region Intermediate lung Peripheral lung region region Chest physiotherapy 34 0 ± 3 5* 30 5 i 9 5* 39.5 i 4-5* 34-5 i 2-5* Cough 26-0 ± 5 0* 31-0 + 6 5* 24-5 + 4 5* 14-0 + 3 0 Control 5 5 + 4 0 5 0 i 4 5 5 0 d 4 0 8-0 + 3 0 Thorax: first published as 10.1136/thx.36.9.683 on 1 September 1981. Downloaded from

686 Bateman, Newman, Daunt, Sheahan, Pavia, Clarke because of extreme airway narrowing. Thus the lung regions in patients with stable chronic airways shearing of secretions by cough may well be limited obstruction and highlights the limitation of coughing to the trachea and first two airways generations,'3 alone. resulting in retention of secretions in peripheral airways. The group mean PEFR in our patients References was greatly reduced (38 ± 6 SD % predicted value). Shearing of secretions by cough would therefore MacMahon C. Breathing and physical exercises for use in be expected to be limited to central airways. cases of wounds in the pleura, lung and diaphragm. Both the quality for example, viscosity and Lancet 1915 ;2 :769-70. 2 Jones NL. Physical therapy. Am Rev Respir Dis 1974;110: elasticity-and quantity of tracheobronchial secre- 132-6. tions may modify the efficacy of a given cough." 3Murray JF. The ketchup-bottle method. N Engl J Med The interaction of elasticity and viscosity is complex 1979 ;300:1155-7. and difficult to study in man, the effect on clearance 4Bateman JRM, Newman SP, Daunt K, Pavia D, Clarke SW. Regional lung clearance of excessive bronchial being largely unknown. The quantity of bronchial secretions during chest physiotherapy in patients with secretion is more easily investigated. The lung has stable chronic airways obstruction. Lancet 1979 ;1 :294-7. been compared to a ketchup bottle3-the bottle 5 Oldenburg FA, Dolovich MB, Montgomery JM, Newhouse must contain some ketchup before it can be MT. Effects of postural drainage, exercise and cough on mucus clearance in chronic bronchitis. Am Rev Respir emptied. Excessive secretions must be present in the Dis 1979;120:739-45. lung before they can be removed either by cough or 6 Thomson ML, Pavia D, McNicol MW. A preliminary physiotherapy. Camner et al,14 using a radioaerosol study of the effect of guaiphenesin on mucociliary tracer method, found that cough enhanced total lung clearance from the human lung. Thorax 1973 ;28:742-7. 7Snedecor GW, Cochran WG. Statistical methods. Sixth clearance in six patients with lung disease and edition. Ames, Iowa: Iowa State University Press. sputum, but proved ineffective in normal subjects 1968. and in two patients with no sputum. Previous 8 Bertrand A, Puchelle E. Mesure de la clearance muco- negative studies evaluating chest physiotherapyl5-20 ciliaire des bronches proximales chez le bronchitique chronique. Path Biol 1977;25:623-7. may have resulted in part from the patients lacking 9 Lourenco RV, Loddenkemper R, Carton RW. Patterns ofcopyright. increased secretions. The group mean daily sputum distribution and clearance of aerosols in patients with production in our study was 160 ml, confirming bronchiectasis. Am Rev Respir Dis 1972;106:857-66. the presence of excessive lung secretion. In health, 10 Wood RE, Wanner A, Hirsch J, Farrell PM. Tracheal mucociliary transport in patients with cystic fibrosis and bronchial secretions removed by mucociliary clear- its stimulation by terbutaline. Am Rev Respir Dis 1975; ance amount to about 30 ml/day. 111:733-8. Our results differ from those of Oldenburg et al.5 Clarke SW, Jones JG, Oliver DR. Resistance to two-phase http://thorax.bmj.com/ Using a radioaerosol method, these workers found gas-liquid flow in airways. J ApplPhysiol 1970;29:464-71. 12 Harris RS, Lawson TV. The relative mechanical effective- cough to be an effective manoeuvre for accelerating ness and efficiency of successive voluntary coughs in peripheral lung clearance in patients with chronic healthy young adults. Clin Sci 1968 ;34:569-77. bronchitis. The studies differ in several ways. 13 Clarke SW. The role of two-phase flow in bronchial Firstly, in our patients sputum volume was greater clearance. Bull Physiopathol Respir 1973;9:359-72. 14 Camner P, Mossberg B, Philipson K, Strandberg K. (50-300 ml versus 10-120 ml) and airways obstruction Elimination of test particles from the human tracheo- more severe (FEV1 = 37 + 13 (SD) % versus bronchial tract by voluntary coughing. Scand J Respir 58 ± 21 (SD) % predicted value). Their coughs were Dis 1979 ;60:56-62. 11 Laws AK, McIntyre RW. Chest physiotherapy: A physio- perhaps less efficient. Secondly, the initial distri- on September 24, 2021 by guest. Protected logical assessment during intermittent positive pressure bution of radioaerosol tracer particles in Oldenburg's ventilation in respiratory failure. Can Anaesth Soc J study was predominantly central, whereas our 1969 ;16 :487-93. particles were deposited more uniformly throughout 6 March H. Appraisal of postural drainage for chronic the lung. Furthermore, the computer-selected lung obstructive pulmonary disease. Arch Phys Med Rehabil 1971 ;52:528-30. regions are not directly comparable. It is possible, 17 Campbell AH, O'Connell JM, Wilson F. The effect of therefore, that we were monitoring clearance from chest physiotherapy upon the FEV1 in chronic bron- more pheripheral airways. chitics. Med J Aust 1975;1:33-5. Chest physiotherapy consists of postural drainage, 18 Graham WGB, Bradley DA. Efficacy of chest physiotherapy and intermittent positive-pressure breathing vibration, shaking, and percussion. The effect of in the resolution of pneumonia. N Engl J Med 1978 ;299: postural drainage has been evaluated by several 624-7. workers16 21-23 with conflicting results, while neither 19 Newton DAG, Stephenson A. Effect of physiotherapy on vibration, shaking nor percussion alone has been pulmonary function. Lancet 1978;2:228-9. 20 Newton DAG, Bevans HG. Physiotherapy and inter- examined. The present study confirms the value of mittent positive-pressure ventilation of chronic bron- chest physiotherapy as a whole in accelerating the chitis. Br Med J 1978;2:1525-8. clearance of excessive bronchial secretions from all 21 Lorin MI, Denning CR. Evaluation of postural drainage Thorax: first published as 10.1136/thx.36.9.683 on 1 September 1981. Downloaded from

Is cough as effective as chest physiotherapy in the removal ofexcessive tracheobronchial secretions ? 687

by measurement of sputum volume and consistency. Dis 1977;115:1009-14. Am JPhys Med 1971;50:215-9. 23 Wong JW, Keens TG, Wannamaker EM et al. Effects of 22 Chopra SK, Taplin GV, Simmons DH, Robinson GD, gravity on tracheal mucus transport rates in normal Elam D, Coulson A. Effects of hydration and physical subjects and in patients with cystic fibrosis. Pediatrics therapy on tracheal transport velocity. Am Rev Respir 1977;60:146-52. copyright. http://thorax.bmj.com/ on September 24, 2021 by guest. Protected