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Article

Effectiveness of an Educational Intervention on Inhaler Technique Proficiency in Chronic Obstructive Pulmonary Disease: A Single-Center Quality Improvement Study

1
Pneumology Division, Hôpitaux Universitaires de Genève, 1205 Geneva, Switzerland
2
Internal Medicine, Hôpitaux Universitaires de Genève, 1205 Geneva, Switzerland
3
Boehringer Ingelheim (Schweiz) GmbH, 4057 Basel, Switzerland
4
Pneumology, Ospedale Regionale di Lugano, 6900 Lugano, Switzerland
*
Author to whom correspondence should be addressed.
J. Respir. 2022, 2(3), 139-146; https://doi.org/10.3390/jor2030012
Submission received: 5 July 2022 / Revised: 15 August 2022 / Accepted: 25 August 2022 / Published: 2 September 2022

Abstract

:
Albeit inhalation therapy is the cornerstone in chronic obstructive pulmonary disease (COPD) treatment, inhaler technique is rarely evaluated, and training materials are often insufficient. In this single-center study, we aimed to evaluate the effectiveness of a teaching session complemented by a flyer on inhaler technique in COPD patients and to evaluate the perceived quality of the flyer. A total of 30 participants with stable COPD who had never used a soft mist inhaler before (Respimat®, Boehringer Ingelheim) received a brief teaching session on proper inhaler technique complemented by a flyer (visit 1). The teaching intervention was completed by a pulmonologist. Epidemiological and clinical characteristics of COPD were collected by a questionnaire, and the ability to properly handle the inhaler was assessed. After 14 days, inhaler handling was re-evaluated, and patients were asked to rate the flyer (visit 2). After the initial training, proper inhaler handling was achieved in 80.0% of patients. Inhaler proficiency was maintained after 14 days (83.0% of the patients used the Respimat® correctly, p-value > 0.99). The flyer was considered at least good by 27 patients (90.0%). This study indicated that the administration of an educational intervention resulted in persistent good competence in inhaler technique at a 14-day follow-up.

1. Introduction

Chronic obstructive pulmonary disease (COPD) is a common (with a global estimated prevalence of 13.1%) [1], preventable, and treatable disease, whose main characteristics are persistent respiratory symptoms and airflow obstruction. COPD is a global health problem that causes significant morbidity and mortality. It is the third leading cause of death worldwide [2]. The natural history of COPD frequently includes acute exacerbations, which is an acute deterioration of respiratory symptoms beyond the normal daily variation, warranting a treatment [3]. Although most exacerbations are infectious, usually due to viral—or less commonly, bacterial triggers—many other factors can precipitate an exacerbation, such as suboptimal inhaler technique [4,5]. Since early reports, the Global Initiative for Chronic Obstructive Lung Disease (GOLD) has emphasized the importance of assessing inhalation technique and adherence at every opportunity [6]. Inhaler technique comprises manipulation, preparation, and inhalation. Several subsequent studies have reported discouraging data on the rate of inhaler device mishandling [7,8]. As clearly reported by Molimard et al. [9], inhaler handling errors are very common, being described in as many as 89.3% of patients using an inhaler, and critical errors (defined as errors that prevent the drug from reaching its target) in up to 46.9% of patients. Thus, overall capacity in inhaler use appears to be at least poor, regardless of the inhaler device used. Other studies have confirmed these data [10,11]. For the above reasons, a comprehensive approach to inhaler device handling technique is urgently needed.

2. Materials and Methods

2.1. Case Definition

COPD was diagnosed according to the presence of obstructive respiratory disease as defined by the Global Lung Initiative (GLI) [12] in patients with characteristic symptoms and a history of exposure to risk factors. Stability of COPD was defined as the absence of acute exacerbations in the preceding 4 weeks.

2.2. Participants and Study Design

Participants with stable COPD were enrolled consecutively during pulmonary outpatient visits. Patients included had to be older than 18 years, have a formal diagnosis of COPD made by spirometry, and have a new prescription for a soft mist inhaler (Respimat®, Boehringer Ingelheim). We planned to enroll a limited number of patients in this exploratory local quality improvement project, as this practice was reported to be preferable for rapid process improvement [13]. Overall, two visits were planned (Figure 1): at recruitment and at a complimentary follow-up visit after 14 days. During the first visit, patients underwent a teaching session by a pulmonologist on how to appropriately manage their inhaler device and received a flyer with written instructions and an attached therapy diary. We distributed the standard 3-page Respimat® flyer provided by Boehringer Ingelheim (available in the Supplementary Materials, Figure S1). This flyer was developed by a group of respiratory physiotherapists based on patient needs to make it as practical as possible. Subsequently, patients were administered a questionnaire to collect key epidemiological and clinical characteristics, and an assessment of their ability to handle the inhaler device correctly was performed at the end of the teaching session. At the follow-up visit, an evaluation of newly acquired inhaler technique was performed, and a second questionnaire was administered to assess the perceived quality of the flyer in addition to the effective use of the diary.
The primary aim of the study was to evaluate the effectiveness of a structured educational intervention on inhaler technique proficiency and on the maintenance of the acquired proficiency in the short term. We defined inhaler technique proficiency as the ability of a patient to comply with all the steps explained during visit 1 and resumed in the flyer. The secondary aim was to assess the perceived quality of the flyer. Our hypothesis was that a brief structured intervention would improve inhaler technique and that the acquired skill would be maintained at a 14-day follow-up.

2.3. Statistical Analysis

Qualitative data were summarized as absolute values with the corresponding percentages. The inhaler technique at the two timepoints was evaluated by Fisher’s exact test. All tests were performed two-sided, and a p-value < 0.05 was considered statistically significant. Statistical analysis was performed using GraphPad Prism 8 software (GraphPad Software, Inc., La Jolla, CA, USA).

3. Results

We enrolled 30 consecutive patients with stable COPD from February to October 2019. An overview of the relevant demographic and clinical characteristics of participants is provided in Table 1. All enrolled patient attended the second visit (n = 30, 100.0%).
Regarding inhaler technique (manipulation, preparation, and inhalation), at visit 1, at the end of the teaching session, 24 patients (80.0%) used the inhaler device correctly. At visit 2, after two weeks, twenty-five patients (83.3%) used the inhaler device correctly (p-value > 0.99).
In Figure 2, we report the usage instructions contained in the Respimat® flyer. During the first visit, the flyer was explained to each enrolled patient, and 22 (73.3%) patients asked questions about the content of the flyer, especially about step 2 (n = 11, 45.8%). The steps considered the most poorly explained were steps 2 and 6. The use and usefulness of the diary were explained to 29 patients (96.7%). At visit 2, the flyer was rated as very good by 21 patients (70.0%) and good by 6 patients (20.0%). On this occasion, the steps considered the most poorly explained were steps 4 and 6. Twenty-nine patients (96.7%) used the diary between the two visits. The results of the questionnaires administered at visits 1 and 2 are presented in Table 1 and Table 2, respectively.

4. Discussion

Our study showed that a simple, rapid, and structured educational intervention, such as a teaching session complemented by a flyer developed pragmatically by a group of respiratory physiotherapists based on patient needs, resulted in good overall inhaler application (80.0% of the COPD patients used the inhaler correctly). Patients’ acquired ability was maintained for up to 14 days (83.0%, p-value > 0.99). These findings show the effectiveness of the proposed intervention in developing proficiency in inhaler technique and maintaining this proficiency in the short term and are of importance considering the error rate reported in the literature and its dismal consequences. Molimard et al. and Navaie et al. indicated an overall inhaler handling error rate of up to 89.3%, with critical errors preventing the drug from working in up to 46.9% of patients [9,10]. Sanchis et al., in a systematic review, showed that over the past four decades, the overall prevalence of correct handling was 31%, and this figure has not improved over time, prompting the implementation of structured educational interventions [14]. On the other hand, poor inhaler technique was reported to be linked to poor clinical control [7,15] and to increased health costs [16]. In general, all inhalers, when correctly used, show no significant differences in treatment efficacy [17,18].
Few studies have looked at the effect of interventions in creating and maintaining proficiency in inhaler technique. A seminal study by Kessel et al., which included 4529 patients aged 6 years and older in a primary care setting, showed that, after professional instruction and despite adequate use at the initial visit, up to 10.2% of elderly patients and 3.2% of patients in general were using their device incorrectly at a 2-week follow-up [19].
Our results further emphasize the importance of teaching, supported by the use of appropriate information material, to reduce errors in the use of inhalers.
Recently, several innovative developments have advanced the field of inhaler device design. Inhaler devices require the coordination of patients between actuation and inspiration regardless of the type and characteristics of the inhaler. Therefore, the patient’s ability to properly use the device is critical to providing successful treatment. In fact, the perfect inhaler does not yet exist, and each inhaler device has its pros and cons. It is well-established that successful treatment depends as much on the inhaler device and the chosen drug as it does on the patient’s ability to handle the inhaler itself. It has been shown in three randomized controlled trials (RCT) that various educational interventions effectively improve patient proficiency and proper handling of inhaler devices, although two of these trials did not evaluate the maintenance of this proficiency [20,21]. Park et al. showed that video education was not inferior to face-to-face education in terms of the number of critical handling errors at 4- and 12-week follow-ups [22]. GOLD guidelines have taken these findings into consideration and therefore recommend that proper inhalation technique is checked at each visit. However, the frequency of inhaler technique re-evaluation has not yet been established, as most studies have not addressed this issue. Various types of educational interventions have proven useful, including video intervention, the delivery of a flyer, and face-to-face teaching by a physician or health care provider. However, the impact of an educational intervention to improve inhalation techniques on hard clinical outcomes has not yet been demonstrated, and further research in this area is therefore warranted [23,24,25].
In summary, more than the intervention itself, it is important to systematically monitor inhalation technique and ideally implement a standardized intervention to ensure reproducibility in daily clinical practice. We propose that a face-to-face education complemented by a flyer develops proficiency in inhaler technique and maintains this proficiency at a 2-week follow-up.
Our study has several limitations. The sample size is small, the follow-up period of 14 days could be seen as too short, the study was conducted in only one center, a control arm and randomization were not planned, and selection biases may have occurred because of the inclusion of patients attending a pulmonary visit. However, we think that these limitations can be justified by the local quality improvement aim of the study, and a 2-week follow-up has already been used in the literature. Our study has the merit of showing that even a brief teaching session, complemented by a flyer, can achieve adequate levels of effectiveness in inhaler technique proficiency and maintain it at a 2-week follow-up. Although we used the Respimat® device exclusively, we expect our results to be generalizable to other devices.

5. Conclusions

In conclusion, we report that a simple, structured, and inexpensive educational intervention (teaching session complemented by a flyer) showed efficacy in developing proficiency in inhaler technique and maintaining this proficiency in the short term.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/jor2030012/s1, Figure S1: Respimat® flyer (Italian version).

Author Contributions

Conceptualization, P.G. and J.P.D.; Methodology, P.G. and J.P.D.; Investigation, P.G. and A.V.; Writing—original draft preparation, M.M.; Writing—review and editing, M.M., A.T. and J.P.D.; Visualization, M.M. and J.P.D.; Funding acquisition, P.G. All authors have read and agreed to the published version of the manuscript.

Funding

For this project, we received funding from Boehringer Ingelheim, who organized the physiotherapist’s workshop and provided the creation, design, and printing of the Respimat® flyer. The funding number was BI:0362//17.

Institutional Review Board Statement

This study was conducted in accordance with the Declaration of Helsinki. This study was notified to the ethics committee; however, ethical review and approval were waived (ethics committee decision: CER-VD/Req-2017-00753).

Informed Consent Statement

Informed consent was obtained from all subjects involved in the study.

Data Availability Statement

All data from the study are available within the manuscript or be provided within the Supplementary Materials (see in the previous section: Supplementary Materials).

Acknowledgments

We thank all the staff of the pneumology department of Ospedale Regionale di Lugano for their kind work and relentless contribution. We thank Katharina Bakhaus, Alcedis GmbH, Giessen, Germany, for medical writing assistance.

Conflicts of Interest

The authors declare no conflict of interest. The funders were involved in the design of the study, in the interpretation of data, in the writing of the manuscript, and in the decision to publish the results.

References

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Figure 1. Study design and visit schedule.
Figure 1. Study design and visit schedule.
Jor 02 00012 g001
Figure 2. Device handling instructions (as in Respimat® flyer). Handling instructions are shown in pictures and supported by short text passages. The correct order is ensured by sequential numbering of the individual handling steps.
Figure 2. Device handling instructions (as in Respimat® flyer). Handling instructions are shown in pictures and supported by short text passages. The correct order is ensured by sequential numbering of the individual handling steps.
Jor 02 00012 g002
Table 1. Patient demographics and clinical characteristics at visit 1.
Table 1. Patient demographics and clinical characteristics at visit 1.
Questionnaire Visit 1n (%)
Number of patients30 (100.00)
Age
  ≤501 (3.33)
  51–605 (16.67)
  61–706 (20.00)
  71–8015 (50.00)
  81–903 (10.00)
Sex
  Female19 (63.33)
  Male11 (36.67)
Year COPD was diagnosed
  20071 (3.33)
  20151 (3.33)
  20162 (6.67)
  20176 (20.00)
  20189 (30.00)
  201911 (36.67)
GOLD stage
  13 (10.00)
  220 (66.66)
  37 (23.33)
Was the explanation with the flyer successful?
  Yes30 (100.00)
Did the patients ask questions?
  Yes22 (73.33)
  No8 (26.37)
If yes: at which step
  16 (27.27)
  211 (50)
  36 (27.27)
  46 (27.27)
  53 (13.63)
  65 (22.72)
  73 (13.63)
  82 (9.1)
Did the Patient follow each step in the flyer instructions?
  Yes24 (80.00)
  No5 (16.67)
  Missing1 (3.33)
If not: which step(s) should be better explained in the flyer?
  22 (6.66)
  31 (3.33)
  41 (3.33)
  62 (6.66)
  81 (3.33)
Was the use of the diary explained?
  Yes  29 (96.67)
  No1 (3.33)
Table 2. Questionnaire at visit 2.
Table 2. Questionnaire at visit 2.
Questionnaire Visit 1n (%)
Number of patients30 (100.00)
Did the patient use the diary?
  Yes29 (96.67)
  No1 (3.33)
Patient Evaluation of the flyer (Scale 1–6 = very bad to very good)
  ≤43 (10.00)
  56 (20.00)
  621 (70.00)
Did the patient follow each step in the flyer instructions for the Respimat®?
  Yes25 (83.33)
  No4 (13.33)
  missing1 (3.33)
If not: which step(s) should be better explained in the flyer
  Before1 (3.33)
  11 (3.33)
  21 (3.33)
  42 (6.66)
  51 (3.33)
  62 (6.66)
Has the last page (Preparation of Respimat®) been shown to the patient, and did he understand it?
  Yes29 (96.67)
  No1 (3.33)
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MDPI and ACS Style

Marando, M.; Tamburello, A.; Diedrich, J.P.; Valenti, A.; Gianella, P. Effectiveness of an Educational Intervention on Inhaler Technique Proficiency in Chronic Obstructive Pulmonary Disease: A Single-Center Quality Improvement Study. J. Respir. 2022, 2, 139-146. https://doi.org/10.3390/jor2030012

AMA Style

Marando M, Tamburello A, Diedrich JP, Valenti A, Gianella P. Effectiveness of an Educational Intervention on Inhaler Technique Proficiency in Chronic Obstructive Pulmonary Disease: A Single-Center Quality Improvement Study. Journal of Respiration. 2022; 2(3):139-146. https://doi.org/10.3390/jor2030012

Chicago/Turabian Style

Marando, Marco, Adriana Tamburello, Jens P. Diedrich, Antonio Valenti, and Pietro Gianella. 2022. "Effectiveness of an Educational Intervention on Inhaler Technique Proficiency in Chronic Obstructive Pulmonary Disease: A Single-Center Quality Improvement Study" Journal of Respiration 2, no. 3: 139-146. https://doi.org/10.3390/jor2030012

APA Style

Marando, M., Tamburello, A., Diedrich, J. P., Valenti, A., & Gianella, P. (2022). Effectiveness of an Educational Intervention on Inhaler Technique Proficiency in Chronic Obstructive Pulmonary Disease: A Single-Center Quality Improvement Study. Journal of Respiration, 2(3), 139-146. https://doi.org/10.3390/jor2030012

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