Improved Metered Dose Inhaler Technique When a Coordination Cap Is Used

Abstract

Background: Patients often experience problems using metered dose inhalers (MDIs), particularly poor coordination between inhalation start and dose actuation (TsIn: time difference between the start of an inhalation and the actuation of a dose), and fast peak inspiratory flow (PIF). We investigated if a coordination cap (CAP), with instruction to prolong inhalation, solved these problems. Methods: Inhalation profiles [PIF, TsIn, inhalation volume (Vi), inhalation time (Ti)] of patients with stable asthma prescribed an MDI were measured using their real-life technique (MDI). Inhalation profiles were then measured with the cap fitted (MDI + CAP). These patients were then instructed to inhale through the MDI + CAP for 5 sec, and inhalation profiles measured (MDI + CAP + TRAIN). TsIn was only measured for the MDI. Results: Resistances of MDI and MDI + CAP were 0.0135 and 0.0243 (cm H 2 O) ½ /(L/min), respectively. Seventyone patients were evaluated, with mean [standard deviation (SD)] forced expiratory volume over 1 sec % predicted normal of 78.3% (21.0). Following MDI, MDI + CAP, and MDI + CAP + TRAIN: mean (SD) PIF was 155.6 (61.5), 112.3 (48.4), and 73.8 (34.9) L/min, respectively ( p < 0.001); mean (SD) Ti was 1.60 (0.60), 1.92 (0.80), and 2.99 (1.03) sec, respectively ( p < 0.001); and Vi was similar between stages. Twelve patients used a slow flow with the MDI alone, but only two of these patients demonstrated good coordination. With the cap in place (which ensures good coordination), the number of patients using a slow flow increased to 25 for MDI + CAP and to 50 following MDI + CAP + TRAIN. Conclusions: The cap with its effect of increasing resistance to airflow combined with the instruction to prolong inhalation time significantly decreased the inhalation flow.

Parameters affecting inhalation therapy adherence in elderly patients with chronic obstructive lung disease and asthma

“…Elderly patients with COPD and asthma might have problems with inhalation according to the type and characteristics of their inhaler device. One of the most important problems during the use of MDI is poor coordination of actuation with inhalation . Dry powder inhalers need to be used at an adequate inspiratory flow rate for effective use in patients.…”

Objective Assessment of Patient Inhaler User Technique Using an Audio-Based Classification Approach

“…However, this method of assessment is subjective, it gives equal rating to all errors, is prone to overestimate patient performance and cannot be used to monitor how patients use their inhaler outside of clinical visits 22 , 23 . Inhaler training devices have been reported to improve patient inhaler user technique 10 , 24 . Devices such as the In-Check Flo-Tone [Clement-Clarke International Ltd, Harlow, UK] can give patients an audible signal once they generate the required inhalation flow rate and has been reported to improve patient inhalation technique in the pMDI 25 .…”

Impact of Inhalation Flow, Inhalation Volume and Critical Handling Errors on Delivered Budesonide/Formoterol Dose in Different Inhalers: An In Vitro Study

“…The present study reports on an apparent inhalation volume dependency for DD for Spiromax, whereas Turbuhaler and Easyhaler showed non-dependency of inhalation volume, a difference that may have impact on clinical outcomes. Patients with COPD have significantly lower inhalation volumes, approximately 2 L, compared to healthy subjects [22][23][24][25][26]. A study by Seheult reported that the mean inspiratory vital capacity (IVC) was 2.13 L (±0.79) [23], whereas Azous et al reported an IVC of 1.82 L (±0.88) in patients with moderate COPD (FEV 1 52% predicted normal), and 1.90 L (±0.90) after enhanced training [26].…”