It is well documented that most patients who rely on medical devices to treat asthma or an allergy do not use the devices properly. Now, a research team has sought to identify the factors associated with incorrect use of metered-dose inhalers (MDIs) and epinephrine autoinjectors and publish their findings in the latest edition of the US Annals of Allergy, Asthma and Immunology
The research team at University of Texas Medical Branch Galveston assessed how 102 patients with an allergy used an epinephrine (adrenaline) auto-injector device and a group of 44 patients who used an MDI to treat their asthma. All the patients were enrolled from adult or paediatric clinics.
They found that only 7% of asthma patients used their MDI properly, and there was only a 16% success rate of patients using an epinephrine auto-injector device properly.
With MDI users, the researchers found that the most commonly missed step was not exhaling fully before activating the inhaler; 66% of imperfect users failed to do this step. Another common error was not shaking the inhaler before taking a second puff.
With patients using the epinephrine auto-injector, the researchers found that the most common error was not holding the unit in place for at least 10 seconds after triggering it; 76% of erroneous users made this mistake. Other common errors included failing to place the needle end of the device on the thigh and failing to depress it with enough force to activate the injection.
Most patients continued to make at least one mistake in using the auto-injector and would have failed to benefit from the potentially life-saving treatment, the researchers say. Asthma patients’ lack of proper use typically resulted in diminished drug delivery.
The study highlights the need for better patient training, including practical demonstrations, in the use of their devices, the researchers say.
Samantha Walker, director of research and policy at the patient charity Asthma UK, says the findings confirm 2008 research published in Respiratory Medicines
which found that a third of people with asthma make mistakes with their inhalers which reduced the effectiveness of their treatment.
The US study follows Asthma UK research published in November 2014 which showed that almost a quarter of UK patients had not had an annual review in the last year and that in total 80% failed to receive asthma care that met basic clinical standards.
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