Optimal Inhalation Profile of Pressurized Metered Dry Powder Inhaler Using a Valved Holding Chamber: A Dynamic Analysis.

: The combined use of a pressurized metered-dose inhaler and valved holding chamber (pMDI+VHC) is recommended to improve efficiency and safety; however, aerosol release is likely to vary with the inhalation maneuver. This study investigated the aerodynamic characteristics and aerosol release features of pMDI+VHC (Aerochamber, Trudell Medical International). : The static and dynamic changes in the airway resistance () during inhalation (withdrawal) through pMDI+VHC were measured.

In Vitro Comparison of Two Blister-Type Inhalers.

Background: Ellipta is a respiratory device that is a successor of the Diskus. A major difference between the devices is that Ellipta, especially the 2-strip type, includes a pair of blisters rather than a single blister as contained in Diskus. This study aimed to compare the particle-release properties and mechanical features of both devices.

Daily inhaled flow profiles and drug release from dry powder inhalers in patients with bronchial asthma.

Background: Inhalation flow profiles may affect particle release from dry powder inhalers (DPIs). Currently available measures include a limited number of laboratory-measured parameters such as peak inhalation flow (PIF) and inhaled volume (inhV). We aimed to investigate whether parameters obtained under such conditions are valid in real-world settings and determine the effective inhalation profile.

[CHARACTERISTICS OF BUDEFORU FOR BUDESONIDE AND FORMOTEROL MIXTURE].

Background: Recently, BudeForu (BF), a generic of Symbicort Turbuhaler (SMB), is widely used in Japan. Although appearance of BF resembles to SMB, several differences in length, weight, and side-hole sizes are seen with precise inspection. As particle releases from the inhalation device is strongly influenced by its mechanical characteristics, we compared their particle release patterns.

Optimal Inhalation Flow Pattern from Turbuhaler Predicted by Laser Photometry.

The emitted dose (ED) from most dry powder inhalers (DPIs) is almost independent of peak inspiratory flow (PIF) above a certain value, which is specific to the individual DPI. However, the ED of the Turbuhaler (TBH) increases linearly with PIF increments. This study investigated the powder clearance and clinical utility of TBH performance features by using the photo-reflection method (PRM), a type of laser photometry.

Correcting Photo Reflection Method Output and Its Application in the Dynamic Analysis of Particle Release from Dry Powder Inhalers.

The photo reflection method (PRM) is used to measure light reflected from particles released from dry powder inhalers (DPIs). This simple method depicts time trajectories of released drugs; however, it underestimates the number of particles at high peak inhalation flow rates (PIFs). In this study, we aimed to correct this underestimation and clarify whether long inhalation is necessary for capsule-type DPIs, using this unique method.

Analysis of Drug Release Dynamics of the Reservoir-type Dry Powder Inhalers.

Objective: Dry powder inhalers (DPIs) are classified as capsule, blister, and reservoir types. Currently, two reservoir-type DPIs, i.e.

[IS IT NECESSARY TO PROHIBIT SIDE-HOLE CLOSURE IN USE OF THE DRY POWDER INHALERS?].

Background: In use of Ellipta (EPT), Diskus (DKS) or Turbuhaler (TBH), an instruction not to close side holes is sometimes given, but validity of such instruction has not been proved.

Method: Using an inhalation simulator we measured peak inhaled flow (PIF), peak inhaled pressure (PIP) and amount of the drug release from these DPIs before and after closure of side holes (SHC). In the case of EPT, incomplete obstruction was also assessed.

Appropriate use of a dry powder inhaler based on inhalation flow pattern.

Background: An optimal inhalation flow pattern is essential for effective use of a dry powder inhaler (DPI). We wondered whether DPI instructors inhale from a DPI with an appropriate pattern, and if not, whether self-training with visual feedback is effective.

Methods: Subjects were 14 pharmacists regularly engaged in instruction in DPI use.

Impact of holding position during inhalation on drug release from a reservoir-, blister- and capsule-type dry powder inhaler.

Objective: To determine whether drug release may be impaired by tilting some dry powder inhalers (DPIs).

Methods: Using an inhalation simulator, we measured drug release from Turbuhaler® (TBH), Diskus® (DKS) and Breezhaler® (BZH) at several peak inhaled flow rates (PIFs) while the DPIs were held at level and tilted (80°). Drug release was then measured from all three DPIs at 0, 30, 60 and 90° of tilt, and capsule rotation was also recorded.

Exhalation immediately before inhalation optimizes dry powder inhaler use.

Objective: Although exhalation immediately prior to inhalation (EPI) from dry powder inhalers (DPIs) is universally advised, its benefit has not been investigated. The objective of this study to assess the effects of EPI on inhaled flow from a DPI.

Methods: We measured peak inhaled flow rate (PIFR) and inhaled gas volume of 25 volunteers unfamiliar with DPIs.

[Resistances of dry powder inhalers and training whistles and their clinical significance].

Background: Flow resistance of dry powder inhaler (DPI) is important information when physician choose a suitable DPI to individual patient. We previously reported flow resistances of several DPIs and training devices. In the present in vitro study, we measured resistances of new DPIs and new trainers.

[Dynamic characteristics of flow trainer for dpi and its clinical relevance].

Background: Trainer devices are widely employed for flow instruction in the use of dry powder inhalers (DPI). However, their aerodynamic characteristics in actual use have yet to be investigated.

Methods: We recorded inhalation flow signals and sounds produced from trainers for Diskus®, Symbicort®, Pulmicort® and Twisthaler® while five volunteers inhaled from the trainers with various inhalation patterns.

[Flow and inspiratory pressure characteristics of In-Check(tm) and training whistles].

Background: The optimal inhalation effort using dry powder inhalers (DPI's) varies with the specific inhaler. Accordingly, the device used for instruction in the proper use of the specific DPI should have physical characteristics similar to the actual DPI. However, the precision with which these devices mimic the actual DPI's has not been established.

Minimal inspiratory flow from dry powder inhalers according to a biphasic model of pressure vs. flow relationship.

Inhalation therapy using the dry powder inhaler (DPI) is now the first choice for obstructive pulmonary diseases. We previously measured relationships between inspiratory pressure (PI) and flow rate of almost all of the DPIs available in Japan, and described an importance of inspiratory efforts. In the present study, we further analyzed the data obtained in the previous study.

[The relationship between inspiratory pressure and flow through dry powder inhaler available in Japan].

Objective: Recently many of the inhaled drugs are provided as dry powder formula and prescribed for such diseases as COPD and asthma exacerbation. Inspiratory flow rate through the dry powder device (DPI) has a significant influence on therapeutic response in these disease conditions. We planned to measure flow vs.

Spirometric and flow-volume curve analysis in rats, and optimal parameters for estimating obstructive impairment.

We obtained flow-volume (F-V) curves in anesthetized rats by applying positive pressure on the body surface. To obtain the best curve, tracheal intubation with either a 12 or 13 gauge catheter and a surface pressure greater than 56 cmH(2)O was necessary. Peak expiratory flow rate (PEFR) and forced vital capacity (FVC) were shown to be optimal parameters for estimation of bronchoconstriction induced by methacholine inhalation while FEV(0.

Decrease in glomerular filtration rate by plasma low-density lipoprotein cholesterol in subjects with normal kidney function assessed by urinalysis and plasma creatinine.

Objective: It has not been well defined whether plasma low-density lipoprotein cholesterol (LDL-C) progresses arteriolosclerosis (arteriosclerosis of small arteries) or not. Estimated glomerular filtration rate (e-GFR) is an indicator of the function of renal arterioles and capillaries of glomeruli. The relationship between e-GFR and plasma LDL-C was studied to estimate the effect of plasma LDL-C on the function of renal arterioles and capillaries of glomeruli to speculate the effect of plasma LDL-C on arteriolosclerosis.

Aerosolized methacholine-induced bronchoconstriction and pulmonary hyperinflation in rats.

The body plethysmography (BPG) is a useful tool for analyzing pulmonary function in small animals because it simultaneously measures airway resistance (R (aw)) and functional residual capacity (FRC). We previously described a BPG with the enclosed environment maintained at body temperature and water vapor-saturated. We found dose-dependent increases in R (aw) in response to inhaled methacholine (Mch) with no apparent increase in FRC in intratracheally intubated rats without paralysis.

Gefitinib-induced lung injury successfully treated with high-dose corticosteroids.

A 55-year-old man was treated with gefitinib for disseminated pleural lesions, 1 year after resection of the left lower lobe for non-small cell lung cancer. After 6 weeks of continuous daily treatment with oral gefitinib, he developed dyspnoea on exertion and a non-productive cough. CXR and CT revealed focal areas of ground-glass opacity (GGO) in the right upper lobe.

Functional residual capacity and airway resistance in rats of COPD model induced by systemic hyaluronidase.

Unlabelled: Chronic obstructive pulmonary disease (COPD) is characterized by obstructive bronchiolitis and parenchymal destruction. In animal models, air space enlargement induced by intratracheal elastase is augmented by prior depletion of lung hyaluronan by hyaluronisase. Recently our colleagues reported that intravenous hyaluronisaein in the absence of elastase produced emphysema-like alveolar dilation [1].

Eosinophilic pleurisy induced by dantrolene.

A 70-year-old male developed eosinophilic pleurisy fifteen years after dantrolene sodium had been started for his spastic paraplegia due to spinocerebellar degeneration. Drug lymphocyte stimulation test (DLST) for dantrolene was positive. After discontinuance of dantrolene, pleural effusion gradually decreased and inflammatory reaction improved.

Impact of Fluticasone Diskhaler on health-related quality of life in asthmatic patients.

Objective: To assess effect of a breath-actuated inhaled steroid, Fluticasone Diskhaler (Flutide) on health-related quality of life in asthmatic patients using Hyland's living with asthma questionnaire (LWAQ).

Subjects And Methods: Randomly selected asthmatic patients filled out the LWAQ (the first study). Then, the eight physicians switched inhaled steroid from pressurelized metered-dose inhaler of beclomethasone (BDI) to Flutide according to their own decision.