Widespread inhaler misuse in COPD patients: Need for training

By Dr. Liji Thomas, MDReviewed by Benedette Cuffari, M.Sc.Aug 25 2024

Study: Prevalence of Critical Errors and Insufficient Peak Inspiratory Flow in Patients Hospitalized With COPD in a Department of General Internal Medicine: A Cross-Sectional Study. Image Credit: AtlasStudio / Shutterstock.com

Chronic obstructive pulmonary disease (COPD) is a chronic lung condition characterized by loss of lung elasticity, which leads to dysfunctional gaseous exchange. COPD is the third leading cause of death worldwide, with over 3.2 million deaths caused by COPD in 2019.

A recent study published in the Journal of the COPD Foundation examines errors in the use or design of inhalers used by hospitalized COPD patients.

Differences in inhaler design

Inhalers are frequently used for the treatment of COPD. Poor inhalation techniques can impact treatment outcomes in COPD by increasing the risk of impaired symptom control, reduced quality of life, exacerbated illness, and hospitalization.  

Dry powder inhalers (DPIs) can provide sufficient therapeutic efficacy if the patient inhales strongly and deeply enough to break up the medication-carrying powder to allow it to coat the small airways. If the patient does not achieve adequate peak inspiratory flow (PIF), exacerbation and hospitalization risk worsens.

Patients with cognitive impairment or poor manual dexterity may not be able to use inhalers as designed. These sources of error and their prevalence among outpatients have been reported in prior publications; however, few studies have examined both errors in technique and low PIF.

These failures among hospitalized COPD patients, including persistent inhaler misuse despite proper training, led to the current study measuring the proportion of inhaler misuse.

About the study

The single-center study included 96 patients treated at the internal medicine department of the Hospital of Fribourg (HRF) in Switzerland between August 1, 2022, and April 3, 2023. The mean age of the patients was 71.6.

All study participants were assessed by a physiotherapist for critical errors in inhalation technique within 72 hours of admission. The evaluation was based on a custom checklist tailored to different types of inhalers.

Critical error was defined as any action that could negatively affect the adequate delivery of the drug to the distal airways. If critical errors were observed, the patient was immediately trained.

Misuse of an inhaler was identified when the patient exhibited critical errors in inhalation technique and/or insufficient PIF. Unsuitable inhalers were defined as those that either provide insufficient PIF or prevent the ability to optimally use the inhaler despite specific training.

PIF was also evaluated with a handheld In-Check Dial G16 device, which measured internal resistance with various inhaler types.

What did the study show?

Inhaler misuse was recorded if either low PIF, one or more critical errors, or both were observed. The modifying effects of age, sex, acute exacerbation of COPD, or any breathing issue were also reported.

An average of three inhalers was used for each patient. Overall, 160 inhalers were assessed.

About 69% of hospitalized COPD patients misused inhalers, 66% made critical errors during inhaler use, and 14% had insufficient PIF. An average of 1.4 and 1.3 and critical errors for every inhaler use were observed, respectively.

After training patients who made critical errors, the number of inhalers associated with these errors significantly decreased. For example, 20.6% of patients continued to experience critical errors after one session of remedial teaching, compared to 9.4% and 5.6% after two and three sessions, respectively.

An inhalation technique that persisted uncorrected, even after two or three teaching sessions, was considered unteachable. Factors contributing to this included impaired cognition, poor fine motor function, and the inability to synchronize inspiration with inhaler activation or hold one’s breath for sufficient time.

Despite proper teaching, twenty-seven inhalers were not suitable for therapeutic use. This proportion was higher when compared to inhalers used for COPD patients admitted for acute exacerbations or respiratory symptoms. Age and sex did not alter these results.

When examined by patient, over 82% of patients misused one or more inhalers, 81% used one or more inhalers with a critical error, and 22% used one with a low PIF. After three teaching sessions, 9.4% continued to experience a critical error with at least one inhaler.

Conclusions

The study findings emphasize important issues that must be considered for the clinical management of hospitalized COPD patients using inhalers. These include the need to quickly identify and correct critical errors in inhalation techniques at every opportunity due to their high frequency. Low PIF complicates inhaler use in 14% of patients overall; therefore, healthcare professionals must consider PIF in their treatment recommendations.

Training the patient reduces critical errors by 45% after one session, with a further decline of 11% and 4% after the second and third sessions, respectively. Despite the benefits of repeated training, a significant proportion of inhalers persistently elude correct usage for various reasons.

Therefore, the utility of an inhaler must be determined based on patient-specific characteristics, and the inhalation technique must be frequently monitored. Both the technique and patient profile may change over time and with treatment, both acutely and over the long term, further necessitating regular evaluations. The presence of a respiratory physiotherapist with expertise in inhaler techniques is also important, as most physicians lack this knowledge or time needed to train patients.

The assessment of the inhalation technique and the PIF should be part of the standard clinical assessment of patients with COPD during hospitalization, regardless of the reason for hospitalization.”