Assessment of inhalation flow patterns of soft mist inhaler co-prescribed with dry powder inhaler using inspiratory flow meter for multi inhalation devices

Abstract

The patients’ inhalation flow pattern is one of the significant determinants for clinical performance of inhalation therapy. However, the development of inhalation flow meters for various inhalation devices has been unable to keep up with the increasing number of newly launched inhalation devices. In the present study, we developed simple attachment orifices for the inhalation flow pattern monitoring system, which are suitable for all commercial inhalers, and investigated the efficacy of the system on the clinical inhalation instruction for patients co-prescribed dry powder inhaler (DPI) and soft mist inhaler (SMI). First, we constructed simple attachment orifices that were adjusted for 13 commercial inhalers, and examined the correlation between orifice and inhalation device. Second, the inhalation flow patterns (peak inspiratory flow rate, PIFR; inhalation duration time, DT) of patients prescribed a combination of DPI and SMI were monitored before and after inhalation instruction. The inhalation resistance of commercial inhalers are listed in the following order; Twincaps® > Handihaler® > Swinghaler® = Clickhaler® > Twisthaler® > Turbuhaler® > Jenuair® > Diskus® = Ellipta® > Diskhaler® > Breezhaler® > Respimat® = pMDI. The pressure drop via orifice was significantly correlated with that via the commercial inhaler. For the confirmation, all participants achieved the DPI criterion of PIFR. On the other hand, 4 participants (6 clinical visits) of 10 experimented participants could not achieve the essential criterion of DT (> 1.5 sec) for SMI, but all participants improved their duration time after inhalation instruction by pharmacists (P<0.05). In the present study, we successfully developed simple attachment orifice suitable for 13 commercial inhalation devices. These data suggested that our simple attachment orifices for the inhalation flow pattern monitoring system can detect patients with inadequate inhalation patterns via SMI.

Dispositivos de inhalación para asma y EPOC: una revisión de la literatura

“…This device has similar steps to Turbuhaler ® , and in a study with 165 patients with asthma and COPD, both devices had more incorrect applications compared with Diskus ® or Ellipta ® (28). Breezhaler ® requires an inspiratory flow greater than 50 L/min for the powder dispersion (56). This is higher than the inspiratory flow rated needed to action the Synchrobreathe device.…”

“…Advantages of this device are its portability and compact use, and its breath actuated action, which does not require coordination, and propellant free characteristics. Ellipta ® requires more than 30 L/min to trigger the medication (56), which could be an issue during exacerbation episodes or advanced stages of disease (51). A study from the Netherlands, with 567 patients with COPD and 162 with asthma, assessed the proportion of patients that made critical and overall mistakes using Ellipta ® and other commonly used inhaler devices such as Diskus ® , metered dose inhalers (MDI), Turbuhaler ® and Breezhaler ® .…”

“…Additionally, the long generation time of the aerosol cloud (approximately 1.5 seconds) facilitates coordination of inhalation and actuation generating higher lung deposition, which is a major problem with pMDIs (55). Because of this characteristic this device does not need a high inspiratory flow, when the patient is given appropriate instruction, and are taught that lower inspiratory flows are optimal (56). Clinical trials have shown that medication delivered by Respimat ® is effective and requires smaller doses in patients with obstructive airway diseases (57).…”

“…Also, employing drug blisters can cause incomplete emptying of the metered dose, reducing the amount of drug delivered to the lung, consequently reducing clinical efficacy (52). As Ellipta ® , this device requires an inspiratory flow higher than 30 L/min to be triggered (56), which could be a disadvantage in certain patients, when compared to other devices. In a review performed by Ninane et al (13) several randomized controlled trials indicate that patients tend to prefer newer and easier to use devices, finding that Diskus ® was preferred by patients before Ellipta ® was released to the market.…”

“…This type of device produces a fair lung deposition with sufficient (about 60 L/min) inspiratory flow (52). As Diskus ® , this device does not have a triggering mechanism, making it entirely dependent on the quality of the patient's inspiration maneuver requiring an inspiratory flow of approximately 60 L/min (52,56) which is twice the inspiratory flow needed for the Synchrobreathe ® device. There are many variations in the design and performance of different types of DPIs, and patients do not use them equally well, making DPIs not easily interchangeable (47,63).…”