SM.TAN1, KJA.TEOH1, LP.NEO1, L.PRABHAKARAN1, CY.GOH1, SY.LEE1, NSB.AZMAN2, P.HOU2, HY.XU1
Tan Tock Seng Hospital1, Woodlands Health2
Dry Powdered Inhalers (DPIs) require adequate patient inspiratory effort for effective medication delivery. Training tools such as individual vendor training kits and inspiratory flow meters may be used to assess patient’s peak inspiratory flow rate (PIFR). We aim to investigate if patients can achieve the optimal PIFR for their DPI.
We included asthmatics on DPI seen in the Tan Tock Seng hospital outpatient respiratory clinic. All patients underwent testing using training kits and an inspiratory flow meter (In-check dial G16) set according to the respective device’s internal resistance.
There were 33 asthmatics included (Mean age 58, 60.6% female, 72.7 % non-smokers). Their mean FEV1 and FVC were 77.2 (+20.2%) and 88.9% (+18.2%) respectively. Their mean Asthma Control Test score was 20 (+4) and had a mean of 0.7 (+ 1.4) exacerbations in the preceding 12 months. They were on DPI for a mean of 3.8 (+ 4.8) years. 84.8% of them were on Turbuhaler device, while the rest were on Ellipta. All patients passed testing with the training kits. There were 8 (24.4%) patients on Turbuhaler with suboptimal PIFR on the flow meter. These patients were not significantly different in demographics, lung function and asthma control indices from those who had optimal PIFR.
Almost a quarter of asthmatics on DPI in our study, who were all on Turbuhaler, had suboptimal PIFR as assessed by a flow meter despite passing the vendor training kit. Larger studies are required to assess the clinical implications of this observation.