Introduction: The European Respiratory Society Oscillometry Taskforce identified that clinical correlates of bronchodilator responses are needed to advance oscillometry in clinical practice. The understanding of bronchodilator-induced oscillometry changes in preterm lung disease is poor. Here we describe a comparison of bronchodilator assessments performed using oscillometry and spirometry in a population born very preterm and explore the relationship between bronchodilator-induced changes in respiratory function and clinical outcomes. Methods: Participants aged 6-23 born ≤32 (N=288; 132 with bronchopulmonary dysplasia) and ≥37 weeks’ gestation (N=76, term-born controls) performed spirometry and oscillometry. A significant bronchodilator response (BDR) to 400mcg salbutamol was classified according to published criteria. Results: A BDR was identified in 30.9% (n=85) of preterm-born individuals via spirometry and/or oscillometry, with poor agreement between spirometry and oscillometry definitions (k=0.26; 95%CI 0.18 to 0.40, p<0.001). Those born preterm with a BDR by oscillometry but not spirometry had increased wheeze (33% vs 11%, p=0.010) and baseline resistance (Rrs 5 z-score mean difference (MD)= 0.86, 95%CI 0.07 to 1.65, p=0.025), but similar spirometry to the group without a BDR (FEV 1 z-score MD= -0.01, 95%CI -0.66 to 0.68, p>0.999). Oscillometry was more feasible than spirometry (95% vs 85% (FEV 1), 69% (FVC), p<0.001), however being born preterm did not affect test feasibility. Conclusion: In the preterm population, oscillometry is a feasible and clinically useful supportive test to assess the airway response to inhaled salbutamol. Changes measured by oscillometry reflect related but distinct physiological changes to that measured by spirometry and thus these tests should not be used interchangeably.

Background: There is considerable variation in recommendations from clinical practice guidelines on when and how to screen for glucose intolerance in people with cystic fibrosis (CF). In terms of glucose tolerance, the Australian Standards of Care state that blood glucose monitoring should be performed to exclude hyperglycaemia on a regular basis. Annual oral glucose tolerance test (OGTT) in patients 10 years or older should be considered and performed in patients with symptoms suggestive of glucose impairment or unexplained weight loss, growth failure or worsening respiratory disease.   In 2018, 13 (14%) of the eligible 99 patients with CF ≥10 years old had an OGTT.  Aims: To evaluate the added benefit of enhanced screening to children and adolescents with CF by improving screening to 50% by the end of 2020.  Methods:  A prospective cross-sectional quality improvement cycles was performed on patients in the CF clinic, ≥11 years for OGTT. Patients were excluded from OGTTs if they were prescribed insulin or prolonged oral/parenteral steroids.  Multiple quality improvement initiatives were tried. Each intervention was done as a plan-do-study-act cycles with refinement between each.  Results:  Screening for CF related diabetes (CFRD) increased in 2020 to 60% of >10 year olds. Four patients had new results suggestive of CFRD and ten had new impaired glucose tolerance.  The most successful strategy was sending letters to families.  Conclusion:  The Australian Standards of Care may require revision, as there may be a benefit of routine screening of all children at certain ages as opposed to waiting for symptoms.

Background: Cystic fibrosis is a common cause of pancreatic exocrine insufficiency. Clinically pancreatic insufficiency is treated as a permanent problem. However, new cystic fibrosis transmembrane conductance regulator (CFTR) protein modulator therapies, like ivacaftor, can change pancreatic function in children. Also, children with residual CFTR function mutations may be pancreatic insufficient in infancy and spontaneously become pancreatic sufficient. Aims: To evaluate the benefit of reviewing pancreatic function, testing and diagnosis, of a cohort and repeat testing to patients with the potential to change function. Methods: all children with cystic fibrosis managed at Perth Children’s Hospital at the end of 2019 were reviewed for pancreatic function testing at diagnosis, genotype and current modulator and pancreatic enzyme replacement therapy use. Children with the potential to change pancreatic function were offered repeat testing. Results: 204 children were included. 11 children were prescribed ivacaftor and four of these became pancreatic sufficient. Five children with a residual CFTR function mutation were pancreatic insufficient at diagnosis. Four became pancreatic sufficient. Conclusion: there is benefit in re-evaluating pancreatic function in children with cystic fibrosis regularly, especially if on ivacaftor or pancreatic insufficient with a residual CFTR function mutation.