scholarly journals Instant velocity and consistency of emitted cloud change by the different levels of canister filling with Metered Dose Inhalers (MDIs), but not with Soft Mist Inhalers (SMIs): a bench study

2017 ◽  
Vol 12 ◽  
Author(s):  
Roberto W. Dal Negro ◽  
Pietro Longo ◽  
Orestepaolo Villanis Ziani ◽  
Luca Bonadiman ◽  
Paola Turco
Keyword(s):  
High Speed ◽  
Real Life ◽  
Metered Dose Inhalers ◽  
Salbutamol Sulphate ◽  
Significance Level ◽  
Significant Difference ◽  
Metered Dose ◽  
Dose Fraction ◽  
Different Levels ◽  
Formoterol Fumarate

Background: Inhalation is the preferred route for respiratory drug delivery, but several factors contribute to the variability of the respirable dose fraction. Instant velocity and the dynamic characteristics of the droplet cloud represent crucial factors. Aim was to measure and compare the instant velocity and the consistency of emitted cloud from five different MDIs (A - Salbutamol sulphate 100mcg, GSK; B - Salbutamol sulphate 100mcg, Valeas; C - Salmeterol xinafoate/Fluticasone propionate 25/125mcg, GSK; D - Formoterol fumarate/Bechlomethasone propionate 6/100mcg, Chiesi; E - Formoterol fumarate/Fluticasone dipropionate 5/125mcg, Mundipharma) and one SMI (Tiotropium bromide 5mcg, Boehringer Ingelheim), at different distance from the nozzle and canister filling. Methods: Measurements were made at 90, 50, and 10% of canister filling, and at 5, 10, and 20 cm from the nozzle, for a total of 972 puffs. A high speed video photography protocol was adopted and high speed cameras (1.200 frames/ sec.) were used. Data were acquired by means of specialized softwares. Temperature, humidity, and vibrations occurrence were strictly controlled during measurements. Statistics: Anova and p < 0.05 were accepted as the minimum significance level. Results: MDIs generated different Instant velocities: MDI B generated the highest, while MDI A the lowest. As expected, velocity decreased in proportion to the distance from the nozzle. Except with MDI C, instant velocity decreased significantly over the first 50% of canister emptying, but dropped by >33% at 90% of emptying with all other MDIs (p < 0–037; p < 0.001; p < 0.005, and p < 0.001, respectively). Instant velocity was extremely lower (p < 0.001) and constant for all levels of canister filling (p = ns) with SMI. All MDIs had a very fast jet phase, ranging 0.01–0.03 s at 10 cm, and 0.03–0.05 s at 20 cm from the nozzle, without any significant difference from each other (p= ns). MDIs generated a cloud similarly tight (p = ns) at 10 and 20 cm from the nozzle, while it was extremely wider and constant with the SMI (p = 0–001). Also the cloud turbulence was minimized during the SMI emission. Discussion and Conclusions: MDIs are characterized by a substantial variability in both their instant velocity and consistency of the emitted cloud at different levels of canister filling. SMI generates a much slower soft mist cloud which is constantly homogeneous and independent of canister emptying. These peculiarities assessed at bench are suggesting a higher dose consistency and a much more effective therapeutic performance also in real life.

scholarly journals Numerical and Experimental Investigation on Key Parameters of the Respimat® Spray Inhaler

Processes ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 44
Author(s):  
Yi Ge ◽  
Zhenbo Tong ◽  
Renjie Li ◽  
Fen Huang ◽  
Jiaqi Yu
Keyword(s):  
High Speed ◽  
Fine Particles ◽  
Geometric Parameters ◽  
Metered Dose Inhalers ◽  
Geometric Pattern ◽  
Long Duration ◽  
Metered Dose ◽  
New Type ◽  
Computational Fluid Dynamics Cfd ◽  
Spray Velocity

Respimat®Soft MistTM is a newly developed spray inhaler. Different from traditional nebulizers, metered-dose inhalers, and dry powder inhalers, this new type of inhaler can produce aerosols with long duration, relatively slow speed, and a high content of fine particles. Investigating the effect of the key geometric parameters of the device on the atomization is of great significance for generic product development and inhaler optimization. In this paper, a laser high-speed camera experimental platform is built, and important parameters such as the geometric pattern and particle size distribution of the Respimat®Soft MistTM are measured. Computational fluid dynamics (CFD) and the volume of fluid method coupled with the Shear Stress Transport (SST) k-ω turbulence model are applied to simulate the key geometric parameters of the device. The effects of geometric parameters on the spray velocity distribution and geometric pattern are obtained. The angle of flow collision, the sphere size of the central divider and the length and width of the flow channel show significant impacts on the spray atomization.

scholarly journals NANO-VESICLES OF SALBUTAMOL SULPHATE IN METERED DOSE INHALERS: FORMULATION, CHARACTERIZATION AND IN VITRO EVALUATION

2017 ◽  
Vol 9 (6) ◽  
pp. 100 ◽  
Author(s):  
Mona G. Arafa ◽  
Bassam M. Ayoub
Keyword(s):  
In Vitro Release ◽  
Pulmonary Delivery ◽  
Entrapment Efficiency ◽  
Reversed Phase ◽  
Molar Ratio ◽  
Metered Dose Inhalers ◽  
Salbutamol Sulphate ◽  
Novel Approach ◽  
Metered Dose

Objective: The present work was aimed to prepare niosomes entrapping salbutamol sulphate (SS) using reversed phase evaporation method (REV).Methods: Niosomes were prepared by mixing span 60 and cholesterol in 1:1 molar ratio in chloroform, SS in water was then added to organic phase to form niosomal SS. Formulations after evaporation of chloroform, freeze centrifuged then lyophilized, were evaluated for particles size, polydispersity index (Pdi), zeta-potential, morphology, entrapment efficiency (EE%) and in vitro release. For pulmonary delivery; metered dose inhalers (MDI) were prepared by suspending SS niosomes equivalent to 20 mg SS in hydrofluoroalkane (HFA). The metered valve was investigated for leakage rate, the total number of puffs/canister, weight/puff, dose uniformity and particle size.Results: The results showed spherical niosomes with 400-451 nm particles that entrapped 66.19% of SS. 76.54±0.132% SS release from niosomes that showed a controlled release profile for 8h. The leakage test was not exceeding 4 mg/3 d, the number of puffs were up to 200puffs/canister, the dose delivered/puff was 0.1 mg and 0.64-4.51μm niosomal aerosol.Conclusion: The results indicate an encouraging strategy to formulate a controlled drug delivery by entrapping (SS) in niosomes which could be packaged into (MDI) that met the requirements of (USP) aerosols guidelines which offering a novel approach to respiratory delivery.

Analysis of Pedestrian Gait and Perception-Reaction at Signal-Controlled Crosswalk Intersections

2000 ◽  
Vol 1705 (1) ◽  
pp. 20-25 ◽  
Author(s):  
Thomas F. Fugger ◽  
Bryan C. Randles ◽  
Anthony C. Stein ◽  
William C. Whiting ◽  
Brian Gallagher
Keyword(s):  
Steady State ◽  
High Speed ◽  
Real Life ◽  
Light Illumination ◽  
Acceleration Rate ◽  
Significant Difference ◽  
Pedestrian Accident ◽  
Walking Velocity ◽  
The Mean ◽  
Walking Speeds

Pedestrian accident analysis and reconstruction remain the most difficult areas for the accident analyst. Although data relating to average pedestrian walking speeds, perception-reaction, and pedestrian accident reconstruction can be found in the literature, proper pedestrian study data pertaining to real-life situations are lacking. Pedestrians were observed at signal-controlled crosswalk intersections, and their perception-reaction to the crosswalk signal, acceleration rate to reach constant walking velocity, and average walking speed once steady state velocity is achieved were determined. Experimental test data collected regarding pedestrian gait analysis, initiation, and steady state walking speeds are presented. “Real world” pedestrian observations were gathered at a variety of intersections, ranging from busy downtown intersections to suburban intersections throughout the greater Los Angeles area. Kinematic data on pedestrian movements were obtained using high-speed digital video. A high-speed video motion analysis system was used to reduce the data and to obtain the mean acceleration and time to steady state walking velocity. Perception-reaction data collected on 288 subjects show a significant percentage of the pedestrians initiating movement within 1 s of Walk light illumination. Some differences were observed when the state of anticipation was being considered, and these results are presented. The mean acceleration (0.14 ± 0.09 g) and steady state velocity (1.36 ± 0.24 m/s) values did not demonstrate a significant difference between males and females. The width of the street or initial state of anticipation did not have an effect on either mean acceleration values or steady state velocities.

Effects of Load Cycling on the Microleakage of Beveled and Nonbeveled Margins in Class V Resin-Based Composite Restorations

2010 ◽  
Vol 11 (5) ◽  
pp. 25-32 ◽  
Author(s):  
Hamideh Ameri ◽  
Marjaneh Ghavamnasiri ◽  
Ehsan Abdoli
Keyword(s):  
High Speed ◽  
Class V ◽  
Significance Level ◽  
Gingival Margin ◽  
Composite Restorations ◽  
Nail Polish ◽  
Significant Difference ◽  
Load Cycling ◽  
Composite Restoration

Abstract Aim This study evaluated the influence of mechanical loading and thermocycling on microleakage of class V resin-based composite restorations with and without enamel bevel. Methods and Materials Sixty class V cavity preparations measuring 3.0 mm wide (mesiogingivally) x 2.0 mm high (occluso-gingivally) x 1.5 mm deep with the occlusal margin in enamel and the gingival margin in cementum were prepared on the buccal surfaces of human premolars using a #12 diamond round bur (Drendel & Zweiling Diamant GmbH, Lemgo, Germany) in a high-speed, water-cooled handpiece. The specimens were then divided into two groups of 30 specimens each, based on the type of enamel cavosurface margin configuration as beveled or nonbeveled (butt joint). After restoring the preparations with a flowable resin-based composite (Tetric Flow, Ivoclar Vivadent-AG, Schaan, Liechtenstein) and finishing and polishing with sequential discs (Sof-Lex Pop-on, 3M-ESPE, St. Paul, MN, USA), the teeth were stored at 37°C and 100 percent humidity. Twenty-four hours later, half of the specimens in each group (nonbeveled “N” or beveled “B”) were exposed to a cycling loading for 250,000 cycles to simulate occlusal loading and assigned to two subgroups (NL+ or BL+), while the remainder of the specimens in each group were only maintained in a 100-percent-humidity environment, without any cyclical loading, until tested (NL– or BL–). The specimens were sealed with sticky wax (Kemdent, Associated Dental Products, Swindon, UK) and nail polish. The apical foramen of each tooth was sealed with sticky wax and the rest of the tooth was covered with nail varnish, except for an area within 1.0 mm around the composite restoration. To detect marginal leakage, all of the samples were stored in a 0.5 percent basic fuchsine solution for 24 hours. The specimens were then sectioned longitudinally using a low-speed diamond blade (IsoMet, Buehler Ltd., Lake Bluff, IL, USA), machined, and evaluated under 25X magnification using a stereomicroscope (M9, Wild Heerbrugg, Switzerland). The specimens were scored on a scale from 1 to 4 on the degree of dye penetration. The qualitative data were analyzed by the Mann- Whitney U test at a 5 percent significance level (p<0.05). The null hypothesis of this study was that there is no difference in microleakage between beveled and nonbeveled class V buccal preparations in premolar teeth restored with resinbased composite and subjected to simulated occlusal loading and thermocycling. Results In each group the gingival margin showed significantly more microleakage than the enamel margin (p<0.05). Load cycling did not result in an increase in microleakage in nonbeveled (p=0.259) or in beveled (p=0.053) occlusal margins. However, the gingival margins showed a statistically significant difference in microleakage after load cycling whether in cavities with enamel occlusal bevel (p=0.004) or in groups without a bevel. This means the enamel margin configuration of the enamel occlusal margin had no effect on decreasing microleakage in the gingival aspect of class V composite restorations. In general, the nonbeveled preparations in this study had significantly less microleakage than the bevel specimens whether they were loaded occlusally or not (p=0.001). Clinical Significance Within the limitations of this in vitro study, no benefit was derived from placing an enamel cavosurface bevel on the occlusal margin of a standardized class V composite restoration located at the cementoenamel junction. The most important consideration is to prevent microleakage along the gingival margin regardless of whether the occlusal enamel margin is beveled. Citation Ameri H, Ghavamnasiri M, Abdoli E. Effects of load cycling on the microleakage of beveled and nonbeveled occlusal margins in class V resin-based composite restorations. J Contemp Dent Pract [Internet]. 2010 October; 11(5):025- 032. Available from: http://www.thejcdp.com/ journal/view/volume11-issue5-ghavamnasiri

Metered-Dose Inhalers and Nebulizers in the Acute Setting

1992 ◽  
Vol 26 (1) ◽  
pp. 92-95 ◽  
Author(s):  
Glenn L. Kisch ◽  
Frank P. Paloucek
Keyword(s):  
Pulmonary Function Tests ◽  
Reaction Rates ◽  
Chronic Obstructive ◽  
Adrenergic Agonists ◽  
Metered Dose Inhalers ◽  
Beta Adrenergic ◽  
Beta Adrenergic Agonists ◽  
English Language Journal ◽  
Significant Difference ◽  
Metered Dose

OBJECTIVE: This article evaluates the current literature comparing beta-adrenergic agonists administered via metered-dose inhalers (MDIs) with nebulizer devices in adult and pediatric patients. These studies focus on the acute treatment of asthma or chronic obstructive pulmonary disease in the emergency department and other acute care settings. DATA SOURCES: English-language journal articles published between 1980 and 1991. STUDY SELECTION: Eight studies that compared beta-adrenergic agonists administered via an MDI or an MDI with a spacing device versus a nebulizer were identified. All of the studies were either poorly designed or had few subjects. By consensus of the authors, all were included in the review. DATA EXTRACTION: Studies were assessed according to methodologic strength (e.g., prospective, comparative). DATA SYNTHESIS: Five studies found no differences between administration methods, one study found metered-dose inhalation to be superior, and another found nebulization to be superior based on observed improvements in pulmonary function tests. There were no significant differences in adverse-reaction rates. When surveyed, subjects preferred MDIs to nebulizers. There were marked variations in doses administered within and between studies. There was no consideration given to doses potentially delivered to the lungs. CONCLUSIONS: There is no significant difference between nebulizers and MDIs plus a spacer with regard to the administration of beta-agonists in the treatment of acute asthma. There are insufficient data to conclusively support the role of spacers in this setting. The choice of a specific delivery method at this time must be determined on an individual basis, taking into account the issues of cost, timeliness of administration, and personnel availability.

Evaluation of Changes in Temperature of Zirconia Frameworks During Grinding Under Different Chair-Side Conditions: An In Vitro Study

2020 ◽  
pp. 232020682095394
Author(s):  
Özgecan S¸ivet ◽  
Özlem Malkondu ◽  
Sercan Küçükkurt ◽  
Ender Kazazoglu
Keyword(s):  
High Speed ◽  
In Vitro Study ◽  
Water Cooling ◽  
Significance Level ◽  
Mean Temperature ◽  
Significant Difference ◽  
Clinical Conditions ◽  
Rotary Instrument ◽  
Difference Test

Aim: To evaluate the changes in the temperature of zirconia during grinding under different clinical conditions. Materials and Methods: A total of 60 zirconia framework specimens were fabricated and divided into groups of 10 specimens each. Two different handpieces, namely, a high-speed handpiece (HSH) and a low-speed handpiece (LSH), were used for grinding with and without water cooling. Fine- and coarse-grit diamond burrs were used with the HSH, separately. The following six groups were created: (a) HSH fine-grit with water cooling, (b) HSH coarse grit with water cooling, (c) HSH fine grit without water cooling, (d) HSH coarse grit without water cooling, (e) LSH with water cooling, and (f) LSH without water cooling. Each zirconia framework was ground until 1 mm3 of the material was removed. Temperature values corresponding to the grinding techniques were compared and statistically analyzed. One-way analysis of variance was used to compare the group parameters, while the Tukey honest significant difference test was used to detect significant differences between the groups. The significance level was set at P <.05. Results: The highest mean temperature was measured in the case of grinding with the LSH without water cooling (54.7 °C ± 11.6 °C), while the lowest mean temperature was observed in the case of grinding with the HSH using the coarse-grit diamond rotary instrument under water cooling (22.6 °C ± 0.6 °C). Conclusions: The grinding of zirconia must be performed with an HSH under water cooling. Further, when water cooling is used, neither the type of handpiece nor the grain type of the rotary instrument used as it has a significant effect on the temperature.

A Novel High-Speed Imaging Technique to Predict the Macroscopic Spray Characteristics of Solution Based Pressurised Metered Dose Inhalers

2014 ◽  
Vol 31 (11) ◽  
pp. 2963-2974 ◽  
Author(s):  
Nicolas A. Buchmann ◽  
Daniel J. Duke ◽  
Sayed A. Shakiba ◽  
Daniel M. Mitchell ◽  
Peter J. Stewart ◽  
...  
Keyword(s):  
High Speed ◽  
Imaging Technique ◽  
Metered Dose Inhalers ◽  
High Speed Imaging ◽  
Spray Characteristics ◽  
Metered Dose ◽  
Pressurised Metered Dose Inhalers

scholarly journals FUNCTIONAL RESPIRATORY IMAGING ASSESSMENT OF BUDESONIDE/GLYCOPYRROLATE/FORMOTEROL FUMARATE AND GLYCOPYRROLATE/FORMOTEROL FUMARATE METERED DOSE INHALERS IN PATIENTS WITH COPD

CHEST Journal ◽  
2020 ◽  
Vol 158 (4) ◽  
pp. A1782-A1783
Author(s):  
M. van den Berge ◽  
Jan De Backer ◽  
Cedric Van Holsbeke ◽  
Wilfried De Backer ◽  
Roopa Trivedi ◽  
...  
Keyword(s):  
Metered Dose Inhalers ◽  
Metered Dose ◽  
Formoterol Fumarate
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