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Background Little is known about the sensations and triggers that provoke cough in patients, or their preferred language to describe their experiences. We have previously collected a list of descriptors covering the themes of triggers, sensations and secretions, generated from individual interviews in a range of respiratory disorders, with a view to developing a questionnaire. Aims To take the key descriptors and present these to focus groups diagnosed with chronic cough, COPD, ILD, asthma, and non-CF bronchiectasis. Methods Five semi-structured focus groups were conducted with 22 participants (7 chronic cough, mean age 67.7 years (range 57-80) 4 female; 5 asthma, age 66 years (60-71) 2 female; 4 COPD, age 68 years (66-73) 2 female; 3 ILD, age 70 years (65-74) 0 female; 3 non-CF bronchiectasis, age 67.3 years (53-77) 2 female). Using simple manifest content analysis, a list of descriptors was derived based on the frequency of use during individual interviews. These were presented to the focus groups, asking them to describe what each word meant to them, the image it conjured up and whether they could identify a most appropriate word. Results All focus groups favoured the terms 'phlegm' over 'sputum' (which was considered too "clinical"), 'irritation' over the word 'tickle' (which was considered too "gentle") and the 'need to cough' over an 'urge to cough'. In contrast, there were distinct differences in some disease groups for example, all groups, apart from COPD, recognised specific foods and eating as triggers of coughing. Similarly, all groups, apart from asthma, identified specific smells and odours as triggers of coughing. Patients with COPD, ILD and non-CF bronchiectasis related to the word 'crackle', but asthmatics only associated this word with "infection" and chronic cough patients did not identify with this terminology. Conclusion These focus group discussions would suggest that whilst some descriptors of cough are felt to be universally appropriate, other descriptors and triggers appear to discriminate between diagnoses. This study will inform the language and content of a future questionnaire to categorise patients by the sensations and triggers provoking their cough. COUGH SOUND INTENSITY: THE DEVELOPMENT OF A NOVEL MEASURE OF COUGH SEVERITY Introduction and ObjectivesCough sound analysis is currently used for the assessment of cough frequency; it is not known if it could be used to assess cough intensity. We investigated the optimal Cough Sound Intensity (CSI) measure by validating it against peak cough flow rate (PCFR). Methods 17 (11 female) patients with stable chronic cough and 15 (8 female) healthy subjects underwent simultaneous measurements of peak cough flow rate and cough sound during voluntary coughs using 2 types of microphones. Subjects were asked to cough voluntarily 10 times at 5 incremental thoracic pressures as measured by an oesophageal balloon catheter. Visual feedback was given to patients. A range of CSI parameters were determined from the P157 P158 only immunopositive for one ...

Introduction and objectivesFew studies have investigated cough frequency in neurological patient groups, in which cough may be impaired or increased in the presence of aspiration. This study aimed to (1) validate the Leicester Cough Monitor (LCM) on a stroke unit, where background coughs might contaminate one patient’s cough recordings; and (2) observe cough frequency longitudinally in a convenience sample of acute stroke survivors.MethodsTo validate the LCM, 15-minute recordings were made from 5 patients on a stroke unit. LCM results were compared with real-time cough counts by a researcher present in the room (visual and auditory). To observe cough frequency longitudinally, 21 stroke survivors underwent 24-hour LCM recordings at baseline (<2 weeks post stroke), week 1 and 4. Participants (14 men, mean (SD) age 60 (15) years) had moderate stroke impairment (median (IQR) NIHSS score 8 (5, 11)) with cortical (n = 9), subcortical (n = 9), brainstem (n = 2) and cerebellar (n = 1) strokes. Five randomly selected recordings were analysed by a second researcher, blinded to subject characteristics and not present during the recordings.ResultsIn the validation study, the real-time observer counted 67 subject coughs plus 81 background coughs in total. The LCM returned a subject cough count of 68, not significantly different to the observer’s count (p = 0.99) with excellent agreement (ICC 0.996, 95% CI: 0.967, >0.999). Inter-rater reliability for LCM hourly cough counts was good (ICC 0.973, 95% CI: 0.789, 0.997). In the longitudinal cohort, average cough frequency was higher at baseline and reduced over time, with wide individual variability (Table 1) and higher cough frequency during day-time. There were no significant associations between cough frequency and sex, age, stroke site, stroke severity, swallowing safety, smoking status or ACE-inhibitor use.Abstract P237 Table 124-hour cough frequency (median, range) following acute stroke. Baseline assessments were conducted within 2 weeks of stroke24-hour cough frequencyBaseline(n = 21)Week 1(n = 20)Week 4(n = 17)Total number of coughs118 (4, 375)60 (6, 217)56 (1, 186)Hourly coughs5 (0, 16)2 (0, 9)2 (0, 8)Day time coughsa86 (4, 282)30 (6, 159)41 (1, 108)Hourly day time coughs6 (0, 20)2 (0, 11)3 (0, 8)Night time coughsa21 (0, 112)18 (0, 58)9 (0, 90)Hourly night time coughs2 (0,11)2 (0, 6)1 (0, 9) aday time: 08:00–22:00, night time: 22:00–08:00.ConclusionsThis study is limited due to the small sample size and should be regarded as exploratory. It was possible to validate the LCM for application on an acute stroke unit. The findings might serve hypothesis-generation: For example, is cough frequency after stroke increased, indicating sub-clinical levels of swallowing impairment and aspiration threat, which trigger frequent protective coughs?

In conclusion, FEV 1 /FIV 1 index has a good correlation with ALSFRS-R (n = 20, r=-0.71, p < 0. 10.1136/thoraxjnl-2014-206260.341 Neural respiratory drive (NRD), measured using the parasternal intercostal muscle electromyogram (EMGpara), relates to lung disease severity as quantified by conventional methods in a range of diseases. Reference data from healthy populations are required for the technique to be used as an independent measure of lung disease severity. EMGpara has previously been expressed as a percentage of that obtained during a maximal inspiratory effort (EMGpara%max), restricting the use of the technique to subjects able to reliably perform such manoeuvres. The aim of this study was to investigate variability of both raw EMGpara (rEMGpara) and EMGpara%max in healthy adults.EMGpara was measured during tidal breathing in 43 healthy adult non-smokers (25 females, median (range) age 32 (19-79) years, mean (SD) BMI 23.4 (3.5) kg/m 2 ), using surface electrodes positioned bilaterally over the second interchondral space. Measurements were made with and without a mouthpiece/pneumotachograph in situ in 20 participants. Repeated measures were obtained within the same testing session in 27 subjects, and at least seven days later in 13 individuals. Spirometry, height, weight, BMI, fat free mass (FFM) via bioelectrical impedance and measures of regional fat distribution (waist/hip ratio and neck circumference) were also recorded.Mean (SD) EMGpara%max and rEMGpara were 5.88 (3.63)% and 5.06 (2.26)mV respectively. Significant relationships were observed between anthropometric measures and rEMGpara and EMGpara%max (Table 1). rEMGpara and EMGpara%max were unrelated to spirometry variables. Median (range) rEMGpara and EMGpara%max increased significantly with the pneumotachograph in place (4.86 (2.11-8.19)mV versus 5.62 (2.47-10.98) mV and 4.77(1.68-17.00)% versus 6.78 (2.35-20.94)%, both p < 0.0001).Analysis of variance by subject was used to assess within-subject variability. Measurement error was higher for EMGpara% max than rEMGpara (upper 95% confidence limit of difference between repeat measures of EMGpara%max 3.14%, versus 2.35 mV for rEMGpara; within-subject coefficient of variation EMGpara%max 30.8% versus rEMGpara 24.5%). rEMGpara appears to be a reproducible marker of NRD. Both rEMGpara and EMGpara%max are influenced by subjects' anthropometry. Further investigation is required to determine whether these influences are technical or physiological and must be considered when the technique is applied clinically or for research, or when developing reference values.

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