A retrospective audit of hospital records evaluating change in respiratory function during hospitalisation for pulmonary exacerbation in a paediatric population with cystic fibrosis

ObjectivesTo determine the rate of change in lung function during hospitalisation in young people with cystic fibrosis using forced expiratory volume in 1 second (FEV1) and sputum expectorated at admission.DesignRetrospective audit of hospital records from 1998 and 2000.SettingTertiary paediatric hospital.ParticipantsOne hundred and twenty-six young people admitted during an acute pulmonary exacerbation.Outcome measuresSputum weight at admission, FEV1, forced vital capacity (FVC) and forced expiratory flow rate. Participants were grouped into bands according to FEV1 severity and expectorated sputum weight at admission.ResultsSignificant differences were found in the rate of change of FEV1 and FVC across FEV1 bands and sputum groups during hospitalisation. Those in the moderate FEV1 band demonstrated a greater rate of change in FEV1 [mean 0.95, 95% confidence intervals (CI) 0.75–1.18] than those in the normal FEV1 band (mean 0.11, 95% CI −0.42 to 0.64). Those in the moderate and severe FEV1 bands had a greater rate of change in FVC (means 0.88 and 0.86, 95% CI 0.63 to 1.13 and 0.56 to 1.16, respectively) than those in the normal FEV1 band (mean −0.07, 95% CI −0.63 to 0.48). Those producing more than 10 g of sputum had a greater rate of improvement in FEV1 (mean 1.03, 95% CI 0.69 to 1.37) than those producing 1 to 10 g of sputum (mean 0.47, 95% CI 0.27 to 0.66). Those producing more than 10 g of sputum had a greater rate of improvement in FVC (mean 1.10, 95% CI 0.79 to 1.41) than those producing 1 to 10 g of sputum (mean 0.51, 95% CI 0.29 to 0.72).ConclusionsIn this cohort, improved rates of change in FEV1 and FVC during hospitalisation were related to FEV1 severity and sputum production at admission.