An audit of antiasthmatic drug inhalation technique and understanding

Systematic Review of Errors in Inhaler Use: Has Patient Technique Improved Over Time?

BACKGROUND

Problems with the use of inhalers by patients were noted shortly after the launch of the metered-dose inhaler (MDI) and persist today. We aimed to assess the most common errors in inhaler use over the past 40 years in patients treated with MDIs or dry powder inhalers (DPIs).

METHODS

A systematic search for articles reporting direct observation of inhaler technique by trained personnel covered the period from 1975 to 2014. Outcomes were the nature and frequencies of the three most common errors; the percentage of patients demonstrating correct, acceptable, or poor technique; and variations in these outcomes over these 40 years and when partitioned into years 1 to 20 and years 21 to 40. Analyses were conducted in accordance with recommendations from Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Strengthening the Reporting of Observational Studies in Epidemiology.

RESULTS

Data were extracted from 144 articles reporting on a total number of 54,354 subjects performing 59,584 observed tests of technique. The most frequent MDI errors were in coordination (45%; 95% CI, 41%-49%), speed and/or depth of inspiration (44%; 40%-47%), and no postinhalation breath-hold (46%; 42%-49%). Frequent DPI errors were incorrect preparation in 29% (26%-33%), no full expiration before inhalation in 46% (42%-50%), and no postinhalation breath-hold in 37% (33%-40%). The overall prevalence of correct technique was 31% (28%-35%); of acceptable, 41% (36%-47%); and of poor, 31% (27%-36%). There were no significant differences between the first and second 20-year periods of scrutiny.

CONCLUSIONS

Incorrect inhaler technique is unacceptably frequent and has not improved over the past 40 years, pointing to an urgent need for new approaches to education and drug delivery.

Assessment of inhalation technique in primary care asthmatic patients using metered-dose inhalers with or without a spacer

BACKGROUND

Asthma is a chronic disease with increasing morbidity and mortality. Although the development of metered-dose inhalers (MDIs) was a landmark in asthma management, their use is burdened by inappropriate training. Inadequate inhalation technique is reported in 24% to 89% of patients. We assessed how a sample of adult asthmatic patients seen in primary healthcare clinics (PHCs) in Riyadh used their metered-dose inhalers (MDI).

PATIENTS AND METHODS

We conducted a cross-sectional survey of asthmatic adults â yen 18 years of age who attended PHCs and used an MDI with or without a spacer device. Patient inhalation technique was observed independently by the primary researcher and a respiratory therapist using a checklist based on US (National Heart, Lung and Blood Institute) asthma management guidelines.

RESULTS

The mean age of the 191 patients in the survey was 40.64 years (range, 18 to 80 years). Fifty-nine percent were females and 41% were males. Most (77%) were illiterate and most (86%) had received previous education on MDI inhalation technique. Ninety-three percent were using an MDI without a spacer, but none could use their MDI without committing at least one error in both groups. In patients using an MDI without a spacer, the most common error was not tilting the head backward slightly and breathing out to residual volume (85%), followed by not breathing in slowly (84%). In patients using an MDI with a spacer, the most common errors were not tilting the head back slightly and breathing out slowly to residual volume (77%), and not holding the breath for 10 seconds (77%).

CONCLUSION

Despite that MDIs are a mainstay in the management of our asthmatic patients, inhalation technique is very poor among our patients.

An exploration of the skills needed for inhalation therapy in schoolchildren with asthma in Taiwan

BACKGROUND

Clinical observation has shown that many asthma-affected children and their parents are not familiar with appropriate techniques for inhaler use. This may result in misuse, overdose, or diminished response of the administered therapeutic drugs, or may even result in unnecessary, repeated hospitalization. Inappropriate inhalation technique is hazardous to the safety of children with asthma and unnecessarily increases costs resulting from unnecessary rehospitalization.

OBJECTIVE

We designed a study to evaluate the skills needed for inhaler use among children with asthma in Taiwan.

SUBJECTS AND METHODS

Schoolchildren with asthma, aged 8 to 13 years, were asked to demonstrate their inhalation technique. The inhalers used in this study were either metered-dose inhalers or dry-power inhalers. Assessment of the inhalation technique was made using a standardized inhaler checklist. A higher score indicates greater skill using the inhaler.

RESULTS

This study surveyed 132 schoolchildren with asthma. Of those, only 23 (17.4%) asthmatic children who received inhalation therapy revealed good compliance with their medication regimens. No child was observed to have completed all inhaler techniques correctly. Those family members who participated in educational programs and who received instruction from health teams had higher scores for the inhaler checklist (P < 0.05). It was found that children who inhaled medication unaided had a better knowledge of asthma, and their drug inhalation technique was also more skillful (P < 0.03). By multiple regression analysis, we found that determinants of a child's skill at performing the inhalation maneuver included: number of asthma attacks within the preceding year, unaided application of inhaler therapy, older subject age, potential for subjects to receive instructions from parents regarding inhaler use, subjects reading related publications, and the family's degree of satisfaction with the physician's educational program. These variables contributed a total of 23% to variance in the subjects' inhalation technique.

CONCLUSION

This study revealed that most asthmatic children being treated with inhaler medication do not use such devices appropriately. More aggressive asthma education is necessary in Taiwan.

Increasing use of inhaled steroids associated with declining asthma mortality

Increasing worldwide asthma prevalence and mortality has led to greater advocacy of inhaled agents, especially steroids. To determine whether corresponding drug usage trends had ensued locally, wholesale data (expressed as defined daily doses (DDDs)/1000 inhabitants/day) were compared for inclusive periods 1984-1986 and 1992-1994. Whereas absolute usage of anti-asthmatics increased by 79%, proportional inhaled usage increased markedly, especially of steroids (571%) and in hospitals. An odds ratio trend analysis revealed asthma mortality from 1992 onward had declined, particularly in males (p < 0.001). In Hong Kong, despite increasing asthma prevalence, more intensive use of anti-asthmatic drugs (especially inhaled steroids) was associated with declining asthma mortality.

Effect of a brief educational intervention on medical students' use of asthma devices

Several studies have shown that a significant percentage of housestaff and attending physicians are deficient in both skill and knowledge of the metered-dose inhaler (MDI). There are no studies involving medical students, or any including the peak flow meter (PFM). The setting was a large health science center with investigators in private conference rooms with individual medical students. Twenty-two medical students in the last semester before graduation were scored in the use of these devices pre-education and post-education (instruction included both discussion and demonstration). Results revealed a lack of skill initially, followed by dramatic improvement after the intervention. The total number of correct steps for each device (MDI with spacer and PFM) improved significantly (p < 0.0001). This group of medical students was deficient in the use of common asthma devices. A short educational intervention was effective in improving skill.

Bronchodilator responses to salbutamol using diskhaler versus metered-dose inhaler

In adults inhaling salbutamol via metered-dose inhalers (MDls) 200 microg doses are recommended, but with diskhalers the manufacturer advocates 400 rather than 200 microg doses. To assess this advice, a partially double-blind, placebo-controlled salbutamol dose response, crossover study (also incorporating MDI doses) was conducted in 12 mild/moderate asthmatics. After active treatment, mean peak expiratory flow rate (PEFR) increments yielded no clinically or statistically significant differences; compared to placebo, respective median differences in PEFR increments (95% Cls) were 10 (-10, 50), 20 (0, 50), and 15 (0, 30) following 400 and 200 microg via diskhalers and 200 microg via MDls. Diskhalers are a suitable alternative for patients with poor MDI technique, but the use of 400 rather than 200 microg salbutamol doses is not supported by evidence.

Inability of physicians to use metered-dose inhalers

The effectiveness of antiasthmatic therapy with metered-dose inhalers (MDIs) is usually limited by defective inhalational technique. This study surveyed the MDI inhalation performance and knowledge of 100 physicians whose performance (demarcated into six stages) and knowledge scores correlated (r = 0.33, p < 0.001). Inhalation performance scores for shaking the canister, full expiration prior to using the MDI, breath holding thereafter, and positioning of the mouth-piece correlated with their corresponding knowledge scores (p < or = 0.02). Training of physicians entailing actual instruction and supervision of inhalational maneuvers may enhance the ability of doctors to use MDIs and facilitate better patient supervision.

Goals of asthma management. A step-care approach

The past 15 years have seen a rise in mortality and morbidity resulting from asthma, despite a concurrent rise in general knowledge about the disease. The step-care strategy recognized these changes in its approach to asthma management; however, this approach should be used only with attempts to control environmental allergens. Step-care therapy requires that patients be categorized by the severity of illness. Step-one therapy is used for mild, infrequent symptoms and involves treatment based primarily on inhaled bronchodilators. Step-two therapy is instituted in all asthmatics except the mildest cases; it involves treatment by inhaled corticosteroids, cromolyn, or nedocromil. Step-three treatment targets cases of severe asthma through the use of oral corticosteroids. In all phases of treatment, however, it should be remembered that patient education is of critical importance. Education improves patient compliance and is critical to the successful treatment of asthma.