Chest physiotherapy: time for reappraisal.

Chest physiotherapy should now be updated with attention to three important features: first, its use should be limited to those patients with actual or potential sputum production and its central aim should be to increase expectoration. Second, it should incorporate the forced expiration technique with postural drainage and omit traditional elements such as percussion and vibration. Third, the additional use of inhaled adrenergic agents and possibly oral high frequency oscillation may increase sputum clearance further.

Use of nebulised saline and nebulised terbutaline as an adjunct to chest physiotherapy.

To determine whether sputum clearance is increased by using nebulised saline or terbutaline as an adjunct to chest physiotherapy, a radioaerosol method (using technetium-99m labelled human albumin millimicrospheres) was employed in eight patients with stable bronchiectasis on four occasions, for comparison of sputum clearance with four different regimens. These were: control, with the patient resting in an upright position; chest physiotherapy, by the forced expiration technique with postural drainage; and chest physiotherapy following five minutes' inhalation of either nebulised normal saline or nebulised terbutaline 5 mg. Use of both nebulised saline and nebulised terbutaline immediately before chest physiotherapy gave a significantly greater yield of sputum than did physiotherapy alone, and terbutaline also significantly increased radioaerosol clearance from the whole lung and from regions of interest. The mechanism is unclear, but this method may provide a simple way of increasing the efficacy of conventional chest physiotherapy.

Impaired mucus clearance in patients with chronic bronchial sepsis, sinusitis and dextrocardia.

Published reports have indicated that patients with Kartagener's syndrome (dextrocardia, sinusitis and bronchiectasis) have no significant lung mucociliary clearance. With a radioaerosol technique we measured over a 6-hour observation period the tracheobronchial clearance of 8 patients with dextrocardia, chronic bronchial sepsis and chronic sinusitis (DC). The tracheobronchial clearance of these patients was significantly reduced (p less than 0.02) compared with that of 29 healthy subjects of similar age. However, even when allowance was made for productive coughing during the observation period, the reduced clearance was much better than anticipated from published reports in patients with Kartagener's syndrome, which confined their observations to a 2-hour period. The tracheobronchial clearance of the DC patients, adjusted for productive coughing, was as bad as that found in an older group of patients with chronic obstructive airways disease who refrained from expectorating during the equivalent test period. Our study implies one or more of the following possibilities: (a) a spectrum of mucociliary impairment in patients with DC; (b) an effective cough clearance deeper in the lung than hitherto believed, and (c) two-phase flow of mucus cephalad as an effective clearance mechanism in patients with DC.

Effect of terbutaline administered from metered dose inhaler (2 mg) and subcutaneously (0.25 mg) on tracheobronchial clearance in mild asthma.

Tracheobronchial mucus clearance was measured in nine mild asthmatics, using an objective radioaerosol technique, on 3 separate days at intervals of 1 week. Immediately after radioaerosol inhalation, drug or placebo was administered via subcutaneous injection (SC) plus metered dose inhaler (MDI)--2 puffs. Three randomized treatments were used: saline placebo SC plus 2 mg terbutaline by MDI (1 mg per puff); 0.25 mg terbutaline SC plus placebo (propellants and surfactant only) by MDI; and double placebo. Changes in lung mucociliary clearance showed an inverse relationship to baseline clearance of both proximal and distal ciliated airways following inhaled terbutaline, whereas terbutaline SC related inversely only to baseline clearance of the distal ciliated airways. This may reflect the surface concentrations of drug, established by each route.

Radioaerosol assessment of mucociliary clearance: towards definition of a normal range.

Radioaerosol measurements of mucociliary clearance have been assessed in relationship to depth of particle penetration into the lung. The tests analysed were performed with 5 microns diameter 99Tcm particles inhaled under standardised conditions but at varying inhalation flow rates. Aerosol lung penetration was assessed by (i) penetration index (PI), a ratio of outer to inner zone radioactivity determined from a gamma camera image; and (ii) alveolar deposition (AD), a measure of activity retained at 24 hours and taken to represent deposition distal to the ciliated airways. Clearance rates in 30 tests on 19 normal non-smokers under the age of 50 varied significantly with aerosol inhalation flow rate, PI and AD. A normal range varying with PI is proposed although normal inter-subject variability remains high even after allowance for PI. Nevertheless 8 out of 12 patients with stable asthma and 21 out of 24 patients with chronic bronchitis demonstrated slow clearance lying outside the PI-based normal range.

Effects of iodopropylidene glycerol on tracheobronchial clearance in stable, chronic bronchitic patients.

We carried out a randomised, double-blind, two-period crossover study in 15 stable, chronic bronchitics to ascertain the effect on tracheobronchial clearance (TBC) of 1 week's treatment with iodopropylidene glycerol (IPG-Organidin), two tablets four times daily compared to matched placebo. TBC was measured by radioaerosol technique. The drug did not significantly alter TBC in the group as a whole but did significantly enhance TBC in 6 patients who expectorated during both placebo and IPG 6-h observation periods. In 4 patients who did not expectorate in either period no change in TBC occurred. In 10 patients who expectorated in either one or both observation periods, a significant positive correlation was found between an index of the patients' sputum produced and improvement in TBC following IPG treatment. IPG can be an effective expectorant in patients with mucus hypersecretion and particularly so in patients with copious sputum production.

Assessment of percussion, vibratory-shaking and breathing exercises in chest physiotherapy.

While gravity-assisted positions (postural drainage) and the forced expiratory technique are known to promote sputum clearance, the additional value of percussion, vibratory-shaking and breathing exercises individually in chest physiotherapy is uncertain. These modalities have been evaluated in 8 patients with copious sputum production (mean: 44 g/day), using an inhaled radioaerosol technique. Tracheobronchial clearance was unaffected by the addition of either vibratory-shaking or percussion with and without breathing exercises to postural drainage. There was however a significant (p less than 0.01) increase in the dry weight of sputum produced during each of these treatments. The combination of postural drainage used in conjunction with the forced expiration technique is responsible for the majority of mucus mobilisation and should form the basis of routine chest physiotherapy programmes; the other modes appear to be of lesser value.

Canary fancier's lung.

A 54-year-old man presented with features consistent with extrinsic allergic alveolitis occurring after contact with his pet birds. Screening of the serum for avian precipitating antibody was negative but canary precipitins were present. Extrinsic allergic alveolitis to his pet canaries was confirmed by inhalation challenge.

Krypton-81m and 5-micron radioaerosol images in asymptomatic asthma: a blind marking assessment.

Gamma camera images recorded during tidal breathing of krypton-81m (81mKr) and after slow inhalation of 99mTc-labelled monodisperse 5-micron polystyrene particles were assessed by three independent observers. Results from 20 symptom-free asthmatic subjects, all with a forced expiratory volume in 1 s (FEV1) at least equal to 75% of the predicted value, were compared with those from 16 healthy non-smoking volunteers. Blind marking scores for the 81mKr images of the asthmatic subjects related significantly to small airways function. Radioaerosol abnormalities in the asthmatic subjects included excessive deposition of the radioaerosol in the central airways and related significantly to small airways function. Radioaerosol imaging performed better than 81mKr imaging at differentiating asthmatic from normal subjects. Radioaerosol abnormalities in patients with poor small airways function probably reflect (1) uneven distribution of ventilation to different regions of the lung periphery and (2) changed patterns of airflow in the bronchial tree. Image abnormalities detected in routine clinical ventilation imaging - with 81mKr or radioaerosol - may sometimes be caused by small airways dysfunction even when the patient's FEV1 is normal.

Measurement of bronchial mucociliary clearance.

We briefly review bronchial mucociliary clearance: one of the non-specific host defence mechanisms operating in the lungs, helping to maintain cleanliness and sterility. We describe in detail the measurement in man of bronchial mucociliary clearance by means of the radioaerosol technique used in our laboratory. We report the use of the technique for detecting impairment of tracheobronchial clearance in patients with chronic bronchitis compared with healthy control subjects. We illustrate whole lung and tracheobronchial retention curves in a patient with Kartagener's syndrome - and also preliminary results on the inter-subject variability of clearance in a small group of patients (n = 5) with this syndrome. In 24 chronic bronchitics studied on three separate occasions intra-subject variability of 6 hr tracheobronchial clearance was 17%, inter-subject variability was 25% - figures commensurate with those reported by other authors.

Assessment of the forced expiration technique, postural drainage and directed coughing in chest physiotherapy.

The Forced Expiration Technique (FET), postural drainage (PD) and directed coughing have been evaluated in 10 patients with copious sputum (mean value 63.3 ml/24 h) with an inhaled radioaerosol method over a 30-min treatment period. FET alone and FET + PD (but not directed coughing) cleared more radioaerosol than during the control period (P less than 0.01). The wet weight of sputum obtained following FET, FET + PD and directed coughing were all significantly greater than control (P less than 0.01). However, sputum obtained by FET + PD was significantly greater than FET alone (P less than 0.05). Both FET and particularly FET + PD have been shown to be more effective than directed coughing alone and it is suggested that these manoeuvres should be incorporated into standard chest physiotherapy.

Drug effects on mucociliary function.

We summarize the findings of 18 clinical studies carried out over a decade to ascertain the effect of 14 pharmacological agents on lung mucociliary clearance. These studies were carried out on a total of 172 subjects/patients and amounted to 443 individual assessments. The objective, in vivo radioaerosol technique was used to measure clearance. Bromhexine, aerosolized hypertonic saline and aminophylline enhanced the clearance of lung secretions. There was some indirect evidence of a speeding up of mucociliary clearance following the administration of prednisolone and the synthetic anticholinergic bronchodilator ipratropium, while hyoscine was found to reduce clearance. There was no effect on clearance of single doses of the beta blockers propranolol and atenolol, the beta 2 adrenergic drug terbutaline, the cholonergic drug bethanecol and the expectorants 2-mercapto-ethane-sulphonate (aerosol) and glycerol guaiacolate. Long term administration (4 - 7 days) of the beta 2 adrenergic drugs terbutaline and clenbuterol also failed to show any effect on lung mucociliary function.

Chest physiotherapy: a review.

Postural drainage enhances mucociliary clearance and produces larger sputum volumes than an equivalent control period in disease characterised by excessive tracheobronchial secretions. Postural drainage, percussion and vibration will improve pulmonary function only in patients with large sputum volumes. There is no evidence that sputum yield is increased by the addition of percussion and vibration. From radioaerosol studies effective cough is limited to central airways. Breathing exercises may be of some immediate value in asthma but are without long term advantages and probably do not alter the ventilation of the underlying lung. IPPB probably does not improve delivery of bronchodilators and is of no benefit (and possible harmful) in the long term treatment of chronic bronchitis. Infective exacerbations of chronic bronchitis not characterised by copious volumes of sputum, uncomplicated pneumonia and routine post-operative states are not indications for chest physiotherapy. The value of regular physiotherapy on ventilation, gas exchange, work of breathing and incidence of infective exacerbations is uncertain but exercise training and rehabilitation of chronic obstructive airways disease improves exercise tolerance and mobility.

Lung mucociliary clearance in rheumatoid disease.

Lung mucociliary clearance rates were measured in 11 patients with rheumatoid disease and found to be unaltered when compared with those of a group of matched control subjects. The results are discussed in relation to the increased incidence of respiratory infection in patients with rheumatoid disease and also to the recently reported finding of increased airways obstruction in these patients.

Diagnostic criteria for pulmonary embolism.

The most important and consistent symptom of acute PE is the sudden onset of dyspnoea unexplained by pneumonia, heart failure, pneumothorax, or exacerbation of airway obstruction. The features commonly remembered such as haemoptysis and pleural rub may be absent in up to two thirds of patients. With previous cardiorespiratory disease the signs and symptoms become nonspecific and a relatively minor PE can produce clinical features more suggestive of a large embolus. Hypoxia and a raised respiratory rate are also suggestive but cannot be relied upon if there is pre-existing cardiorespiratory disease or in the elderly. Although the radiological appearance of an infarct shadow may be recognized, the chest X-ray is frequently nonspecific or normal. A negative perfusion scan excludes any significant emboli and an abnormal perfusion scan is suggestive of PE but not diagnostic; its specificity can be increased considerably if facilities are available for a concurrent ventilation scan. A deep venous thrombosis when present is also indicative of PE, although its absence does not preclude the diagnosis. Factors predisposing to deep venous thrombosis are usually present in the patient with PE. No single diagnostic aid can be relied upon in the diagnosis of PE. As with many illnesses much of the evidence begins with a careful consideration of the presenting history and physical signs. Further help can be obtained from various investigations, but results must be interpreted with consideration of the patient's age and pre-existing health. The final diagnosis may need to be established by pulmonary angiography.