Technical evaluation of Turbuhaler® use in children with bronchial asthma: combination of a checklist and inhalation parameters.

Background: The Turbuhaler^® is a dry powder inhaler (DPI) that is commonly used in the treatment of asthmatic patients aged 5 years and above. Nevertheless, the technique of using the Turbuhaler^® in the real world remains ambiguous. This study aims to evaluate techniques in using Turbuhaler^® by combining a checklist with inhalation parameters and to investigate the association between the patient characteristics and inhaler technique.

Methods: This study recruited asthmatic children aged 4 to 14 years who were using the Turbuhaler^® from The First Affiliated Hospital of Guangzhou Medical University from August 2023 to August 2024. The technique of using Turbuhaler^® was evaluated step by step, and the inhalation parameters of patients were subsequently tested. Influencing factors related to inhaler technique were analyzed by ordered logistic regression analysis.

Results: Of the 141 enrolled patients, 50 (35.5%) scored 10 points on the checklist. Overall, 105 (74.4%), 28 (19.9%) and 8 (5.7%) patients performed good, moderate, and poor inhaler technique, respectively. The three common improper steps were ''exhale to residual volume'' (35.5%), "inhale forcefully and deeply" (13.5%), "rinse mouth after inhalation" (13.5%). The three common inappropriate inhalation parameters were "Effective inspiratory time(EIT) < 2s" (90.8%), "Peak inspiratory flow rate(PIFR) < 60L/min" (41.8%), and "Breath-hold time(BHT) < 5s" (27.0%). In the three groups with good, moderate, poor inhaler techniques, 0, 2 (7.1%), and 2 (25.0%) patients did not reach the minimum PIFR. Meanwhile, 38 (36.2%), 15 (53.6%), and 6 (75.0%) patients did not reach the optimal PIFR, respectively. The results of ordered logistic regression analysis indicated that low medication adherence (P = 0.045), PIFR (P = 0.041), BHT (P = 0.003) and the duration of Turbuhaler^® use (P = 0.009) were the primary factors influencing asthmatic children's inhaler technique.

Conclusion: The improper use of inhalers and inappropriate inhalation parameters are common among asthmatic children. Using checklist and inhalation parameters enables a more comprehensive evaluation of the patients' inhalation maneuvers and inspiratory effort.

Trial registration: This study is registered at Chictr.org with the identifier number ChiCTR2200056579.