Inhalation Technique among Chronic Obstructive Pulmonary Disease Patients using Metered Dose Inhaler and Dry Powder Inhaler: An Observational Study

Abstract

Introduction: Incorrect inhaler technique is a major contributor to poor disease control in chronic respiratory diseases, particularly in low- and middle-income countries where therapeutic optimization is crucial. Studies report incorrect technique in up to 40–80% of
patients, leading to poor drug deposition and increased exacerbations. This study assessed inhaler techniques across different device types among patients with chronic obstructive pulmonary disease.

Methods: A hospital-based descriptive cross-sectional study was conducted among 500 adult patients using dry powder inhalers or metered-dose inhalers with or without spacers. Ethical approval was obtained from the IRC of the institue. Technique was evaluated using a standardized stepwise checklist through direct observation. Categorical variables were expressed as frequencies and percentages.

Results: Of the 500 participants, 298 (59.60%) used DPIs, 202 (40.40%) used metered dose inhalers, of whom 40 (20% of Metered dose inhalers users; 8% of total participants) used a spacer. Among dry powder inhaler users, correct performance was observed in 50%
for deep inhalation and 45% for breath-holding. In Metered dose inhalers users without spacers, coordination between actuation and inhalation was correct in 29%, slow deep inhalation in 27%, and breath-holding in 25%. Metered dose inhalers use with spacers
showed better performance, with correct inhalation in 68% and breath-holding in 60%. Critical inhalation steps showed the low correctness across all devices. Spacer improved performance but did not eliminate inhalation-related errors, highlighting the importance of targeted training.

Conclusions: This study shows that patients using both MDIs and DPIs still frequently use inhalers incorrectly, with the most serious mistakes happening during the inhalation phase.