### Cough

1) All basic scientific articles should refer to cough as a three-phase motor act. For the purposes of acoustic recordings in clinical studies, however, cough should be described as a forced expulsive manoeuvre or manoeuvres against a closed glottis that are associated with a characteristic sound or sounds.

2) All scientific articles should include a clear definition of what the authors have used as their definition of cough.

### Capsaicin and citric acid inhalation cough challenge

1) The methodology for the performance of inhalation cough challenge should be standardised so as to facilitate universal interpretation and comparison of data generated by different laboratories.

2) Comprehensive normal ranges need to be developed using the standardised methodology advocated in the present document.

3) The single-breath concentration–response method using a flow-limited dosimeter is recommended for most experimental protocols.

4) Both C2 and C5 should be recorded.

5) Since there is wide inter-individual variation, cough challenge data have no intrinsic significance, but may usefully be used to follow change in cough reflex sensitivity in an individual.

### Cough induced by inhalation of aqueous solutions

1) Aerosolised aqueous solutions represent a useful experimental tool in cough research.

2) The cough challenge with ultrasonic distilled water (fog) is difficult to standardise since it is highly dependent upon nebuliser output.

3) Consideration should be given to potential adverse events, such as bronchoconstriction and cross-infection.

### Cough monitors

1) No cough monitor is currently the gold standard.

2) Monitors should be developed that are ambulatory, are capable of being digitally processed and permit prolonged (24-h) recording.

3) There is little to commend any particular method of quantifying cough over any other.

### Assessment of quality of life of patients with chronic cough

1) Cough can have profound effects on health status, which can be assessed by cough-specific health status questionnaires.

2) Cough visual analogue scale (VAS, 0–100 mm) should be used to assess cough severity in patients with chronic cough.

3) Patients with chronic cough should be assessed with cough-specific quality-of-life questionnaires in clinical studies.

### Animal models of cough

1) The most useful animal model of cough is …

/pdf/ers-guidelines-on-the-assessment-of-cough-3gr3n85c88.pdf

ERS guidelines on the assessment of cough

Audio-based cough detection has become more pervasive in recent years because of its utility in evaluating treatments and the potential to impact the quality of life for individuals with chronic cough. We critically examine the current state of the art in cough detection, concluding that existing approaches expose private audio recordings of users and bystanders. We present a novel algorithm for detecting coughs from the audio stream of a mobile phone. Our system allows cough sounds to be reconstructed from the feature set, but prevents speech from being reconstructed intelligibly. We evaluate our algorithm on data collected in the wild and report an average true positive rate of 92% and false positive rate of 0.5%. We also present the results of two psychoacoustic experiments which characterize the tradeoff between the fidelity of reconstructed cough sounds and the intelligibility of reconstructed speech.

https://lyle.smu.edu/~eclarson/pubs/2011UbiComp_Cough.pdf

Accurate and privacy preserving cough sensing using a low-cost microphone

BACKGROUND It has been suggested that cough effectiveness can be improved by assisted techniques. The effects of manually assisted cough and mechanical insufflation on cough flow physiology are reported in this study. METHODS The physiological actions and patient self-assessment of manually assisted cough and mechanical insufflation were investigated in 29 subjects (nine normal subjects, eight patients with chronic obstructive pulmonary disease (COPD), four subjects with respiratory muscle weakness (RMW) with scoliosis, and eight subjects with RMW without scoliosis). RESULTS The peak cough expiratory flow rate and cough expiratory volume were not improved by manually assisted cough and mechanical insufflation alone or in combination in normal subjects. The median increase in peak cough expiratory flow in subjects with RMW without scoliosis with manually assisted cough alone or in combination with mechanical insufflation of 84 l/min (95% confidence interval (CI) 19 to 122) and 144 l/min (95% CI 14 to 195), respectively, reflects improvement in the expulsive phase of coughing by these techniques. Manually assisted cough and mechanical insufflation in combination raised peak expiratory flow rate more than either technique alone in this group. The abnormal chest shape in scoliotic subjects and the fixed inspiratory pressure used made effective manually assisted cough and mechanical insufflation difficult in this group and no improvements were found. In patients with COPD manually assisted cough alone and in combination with mechanical insufflation decreased peak expiratory flow rate by 144 l/min (95% CI 25 to 259) and 135 l/min (95% CI 30 to 312), respectively. CONCLUSIONS Manually assisted cough and mechanical insufflation should be considered to assist expectoration of secretions in patients with RMW without scoliosis but not in those with scoliosis.

https://thorax.bmj.com/content/thoraxjnl/56/6/438.full.pdf

Effect of manually assisted cough and mechanical insufflation on cough flow of normal subjects, patients with chronic obstructive pulmonary disease (COPD), and patients with respiratory muscle weakness

Effects of mechanical insufflation-exsufflation on respiratory parameters for patients with chronic airway secretion encumbrance

Noscapine, a phthalideisoquinoline alkaloid derived from opium, has been used as an oral anti-tussive agent and has shown very few toxic effects in animals or humans. Recently, we reported that noscapine binds stoichiometrically to tubulin and promotes microtubule polymerization. Noscapine causes growth arrest of tumor cells in mitosis and induces apoptosis of tumor cells in vitro. Previous experiments also showed that noscapine has potent antitumor activity in mice when administered parenterally or by gastric lavage. Here, we report that the anti-mitotic effect was specific to noscapine since closely related compounds did not inhibit the growth of a lymphoma cell line. In addition, noscapine was shown to be effective in reducing the growth of the lymphoma and increasing the survival of tumor-bearing mice when administered in the drinking water. It is noteworthy that, noscapine showed little or no toxicity to kidney, liver, heart, bone marrow, spleen or small intestine at tumor-suppressive doses. Furthermore, oral noscapine did not inhibit primary immune responses, which are critically dependent upon proliferation of lymphoid cells. Thus, our results indicate that noscapine has the potential to be an effective chemotherapeutic agent for the treatment of human cancer.

Noscapine inhibits tumor growth with little toxicity to normal tissues or inhibition of immune responses.

The cough response of healthy human subjects stimulated by citric acid aerosol. II. Evaluation of antitussive agents.

The effect of a new bronchodilator aerosol on the air flow dynamics of the maximal voluntary cough of patients with bronchial asthma and pulmonary emphysema.

The therapeutic response to steroids administered by inhalation was studied in 71 patients with severe chronic bronchial asthma. This investigation was based on the concept that topically administered steroid would result in a high local concentration of hormone on the bronchial mucosa and might so effect relief of asthma with less of the adverse reactions encountered with systemic steroid therapy. Thirty-five of the 71 patients obtained marked relief with remission in asthmatic symptoms; 23 were recorded as having moderate reduction in wheeze and obstructive dyspnea; and the remaining 13 noted little or no improvement. Clinical response was assessed in conjunction with ventilatory function studies over a period of approximately 12 months. Except for one instance of marked increase in appetite, there were no adverse hormonal reactions.

https://jamanetwork.com/HttpHandlers/ArticlePdfHandler.ashx?journal=jama&articleId=664954&pdfFileName=jama_184_7_010.pdf

Sylvia E. Itkin

Papers

The cough response of healthy human subjects stimulated by citric acid aerosol. II. Evaluation of antitussive agents.

The effect of a new bronchodilator aerosol on the air flow dynamics of the maximal voluntary cough of patients with bronchial asthma and pulmonary emphysema.

Aerosol Steroid Therapy and Chronic Bronchial Asthma