TY - JOUR T1 - Neural respiratory drive during recovery from exacerbations of COPD JF - European Respiratory Journal JO - Eur Respir J VL - 42 IS - Suppl 57 SP - P1918 AU - Eui-Sik Suh AU - Swapna Mandal AU - Michelle Ramsay AU - Meera Kamalanathan AU - Rachel Harding AU - Katherine Henderson AU - John Moxham AU - Nicholas Hart Y1 - 2013/09/01 UR - http://erj.ersjournals.com/content/42/Suppl_57/P1918.abstract N2 - Background: Neural respiratory drive (NRD), obtained from 2nd intercostal parasternal muscle electromyography (EMGpara), is a useful physiological biomarker of treatment failure in acute exacerbations of COPD (AECOPD) (Murphy et al, Thorax 2012). However, the trajectory of NRD change following hospital discharge is unknown. We hypothesised that there would be improvements in NRD, spirometry and symptoms 1 month after discharge.Methods: AECOPD patients were enrolled within 12 hours of hospital admission. EMGpara, spirometry, inspiratory capacity (IC), modified Borg scale and COPD Assessment Test (CAT) score were recorded when medically fit for discharge and at 1 month. NRD (expressed as EMGpara%max) was derived by normalising the per-breath peak inspiratory parasternal muscle EMG activity to a value obtained during a maximal manoeuvre. Data were analysed using paired t- or Mann Witney U tests.Results: 30 hospitalised AECOPD patients were recruited and attended 1 month follow-up. Mean age was 66±9years, 47% male, BMI 27.0±7.2kg/m2 and %predicted FEV1 29.0±9.3. Median length of hospital stay was 2 (IQR 2-7) days. Admission EMGpara%max was 20.3±9.7%. There were improvements in EMGpara%max (15.8±6.3% to 13.1±6.0%; p<0.001), FEV1 (0.76±0.29L to 0.92±0.45L; p=0.002) and IC (1.65±0.54L to 1.90±0.60L, p=0.005) between discharge and 1 month. Surprisingly, there were no improvements in Borg or CAT scores.Conclusions: There was no change in the recorded symptom scores at 1 month following AECOPD. NRD, airways obstruction and hyperinflation were however improved at this point, suggesting that patient-reported symptoms, as measured, may not be a reliable indicator of the changes in respiratory load during recovery from AECOPD. ER -