Valved Holding Chamber Research Articles

Inhaled corticosteroid delivery is markedly affected by breathing pattern and valved holding chamber model.

There is a scarcity of high-quality research on the efficient delivery of inhaled corticosteroids using valved holding chambers (VHCs) in children. The delivered dose (DD) of fluticasone from a metered dose inhaler (pMDI) was tested using four VHCs: AeroChamber plus Flow-Vu (AC), Babyhaler (BH), EasyChamber (EC), and Optichamber Diamond (OD). The in vitro setup included an anatomical child throat model, Next Generation Impactor, and a breathing simulator to generate tidal breathing of a four and a 6-year-old child, and adult type single inhalation. OD showed the lowest proportion of fluticasone trapped in the throat with all breathing patterns. AC showed similar fine particle dose (FPD) in the respirable range (1-5 µm) irrespective of the breathing pattern. For BH, the median FPD 1-5 µm was highest during adult breathing. OD and EC showed higher overall DD and higher doses in the 1-5 µm range with paediatric breathing profiles compared to adult inhalation. The median DD and FPD 1-5 µm were significantly lower with BH compared to any other VHCs during tidal breathing. Compared to EC, the FPD of the other VHCs were skewed towards <2 µm particles. Fluticasone delivery is markedly affected by breathing pattern and VHC model. The observed differences in throat deposition and FPD delivered may have significant clinical implications for side effects and controlling airway inflammation. All VHCs intended for paediatric use should undergo testing using internationally recognised standardised methods incorporating clinically relevant paediatric breathing patterns.

Comparative performance study of paperboard disposable spacers versus commercial valved holding chambers for aerosol delivery

PurposeThe aim of this study is to evaluate and compare the performance, for the administration of fluticasone propionate with a pressurized metered-dose inhaler (pMDI), of two low-tech paperboard spacers versus two commercially available valved holding chambers (VHC). MethodsAccording to the Canadian standard CAN/CSA-Z264.1–02, total emitted dose (TED) and aerodynamic size distribution were measured for the pMDI in combination with 4 different spacers: a homemade paper cup spacer, the DispozABLE® paperboard spacer, the AeroChamber Plus® plastic VHC, and the Vortex® aluminium VHC. ResultsThe two disposable paperboard spacers had a lower TED compared to the aluminium VHC, but delivered more than 2.5 times the dose of fluticasone than the commercial plastic VHC. The 3 antistatic devices (i.e. the aluminium VHC, the paperboard DispozABLE® spacer and the paper cup spacer) delivered a significantly higher dose of fine particles than the less antistatic plastic VHC. Their fine particle fraction was statistically similar to that obtained with pMDI without spacer. This respirable fraction ensures an optimal therapeutic effect. All spacers limited the flow of coarse particles, thus avoiding adverse effects on the trachea and oropharynx. ConclusionWe have shown that inexpensive and low-tech paperboard spacers are interesting alternatives for the administration of aerosols.

Aerosol deposition and emission from a United States Pharmacopeia‐induction port when using a pressurized metered‐dose inhaler with and without a valved holding chamber

AbstractThe testing of pharmaceutical aerosols includes measuring the aerodynamic particle size distribution, which is usually performed on cascade impactors. In the next generation impactor (NGI), the aerosol dose is introduced through an induction port (IP), being separated into different aerodynamic diameter ranges by seven stages and a micro‐orifice collector. The IP plays an important role in estimating the oropharyngeal deposition fraction. While the IP retains mainly large particles, it also tends to retain particles in the respirable range. In this work, the deposition of particles in the IP of an NGI is studied, both experimentally and through computational fluid dynamic (CFD) simulations. Experimental tests are conducted both with the pressurized metered‐dose inhaler (pMDI) alone and in conjunction with a cylindrical valved holding chamber (VHC). For each case, the total mass deposition that occurs in the VHC, IP, and NGI stages is measured, as well as the mass median aerodynamic diameter of the aerosol leaving the IP. The CFD simulations show minimal variations in results regardless of the injection method due to the relatively low velocity and spray angle of the pMDI‐generated aerosol. If the flap‐valve is removed from the VHC, significant particle deposition occurs upstream or within the valve region, with downstream air recirculation contributing to small particle deposition. Based on the CFD results, a correlation is proposed to accurately predict the particle escape fraction of the IP and VHC, which allows estimation of the tannin distribution of particles collected in the NGI stages, especially those corresponding to the range of respirable particles.

Enhancing Inhalation Drug Delivery: A Comparative Study and Design Optimization of a Novel Valved Holding Chamber.

This paper presents an innovative approach to the design optimization of valved holding chambers (VHCs), crucial devices for aerosol drug delivery. We present the design of an optimal cylindrical VHC body and introduce a novel valve based on particle impaction theory. The research combines computational simulations and physical experiments to assess the performance of various VHCs, with a special focus on the deposition patterns of medication particles within these devices. The methodology incorporates both experimental and simulation approaches to validate the reliability of the simulation. Emphasis is placed on the deposition patterns observed on the VHC walls and the classification of fine and large particles for salbutamol sulfate particles. The study reveals the superior efficacy of our valve design in separating particles compared to commercially available VHCs. In standard conditions, our valve design allows over 95% of particles under 7 μm to pass through while effectively filtering those larger than 8 μm. The optimized body design accomplishes a 60% particle mass flow fraction at the outlet and an average particle size reduction of 58.5%. When compared numerically in terms of size reduction, the optimal design outperforms the two commercially available VHCs selected. This study provides valuable insights into the optimization of VHC design, offering significant potential for improved aerosol drug delivery. Our findings demonstrate a new path forward for future studies, aiming to further optimize the design and performance of VHCs for enhanced pulmonary drug delivery.

Dynamic Analysis of Aerosol Release from a Pressurized Metered Dose Inhaler Combined with a Valved Holding Chamber Using Simplified Laser Photometry.

Background: A pressurized metered dose inhaler combined with a valved holding chamber (pMDI+VHC) is used to prevent upper airway complications and improve the efficiency of inhaled drug delivery; however, the aerodynamic behavior of the released particles has not been well investigated. This study aimed at clarifying the particle release profiles of a VHC using simplified laser photometry. Methods: An inhalation simulator comprised a computer-controlled pump and a valve system that withdrew aerosol from a pMDI+VHC using a jump-up flow profile. A red laser illuminated the particles leaving VHC and evaluated the intensity of the light reflected by the released particles. Results: The data suggested that the output (OPT) from the laser reflection system represented particle concentration rather than particle mass, and the latter was calculated as OPT × instantaneous withdrawn flow (WF). Summation of OPT hyperbolically decreased with flow increment, whereas summation of OPT × instantaneous flow was not influenced by WF strength. Particle release trajectories consisted of three phases, namely increment with a parabolic curve, flat, and decrement with exponential decay phases. The flat phase appeared exclusively at low-flow withdrawal. These particle release profiles suggest the importance of early phase inhalation. The hyperbolic relationship between WF and particle release time revealed the minimal required withdrawal time at an individual withdrawal strength. Conclusions: The particle release mass was calculated as laser photometric output × instantaneous flow. Simulation of the released particles suggested the importance of early phase inhalation and predicted the minimally required withdrawal time from a pMDI+VHC.

In vitro-in vivo correlation of aerosol deposition before and after metered-dose inhaler coaching in healthy children

Although pressurized metered dose inhaler (pMDI) education is a routine part of childhood asthma management and encouraging ‘optimal breathing patterns’ (i.e. slowly, deeply, completely, and with a mouth seal on the mouthpiece) is an integral part of recommended pMDI education, there is currently no quantifiable way to determine if a child is inhaling their medication correctly or optimally through a valved holding chamber (VHC). The TipsHaler™ (tVHC) is a prototype VHC device that measures inspiratory time, flow, and volume without changing the properties of the medication aerosol. The measurements in vivo recorded by the tVHC can be downloaded and transferred to a spontaneous breathing lung model to simulate the inhalational patterns in vitro and also determine the deposition of inhaled aerosol mass with each pattern. We hypothesized that pediatric patients’ inhalational patterns when using a pMDI would improve after active coaching via tVHC. This would increase the pulmonary deposition of inhaled aerosols in an in vitro model. To test this hypothesis, we conducted a single-site, prospective, pilot, pre-and-post intervention study paired with a bedside-to-bench experiment. Healthy, inhaler-naïve subjects used a placebo inhaler in conjunction with the tVHC before and after coaching and recorded inspiratory parameters. These recordings were then implemented into a spontaneous breathing lung model during albuterol MDI delivery, and pulmonary deposition of albuterol was quantified. In this pilot study, active coaching resulted in a statistically significant increase in inspiratory time (n = 8, p= 0.0344, 95%CI: 0.082 to ∞). tVHC recorded inspiratory parameters obtained from patients were successfully implemented in the in vitro model, which demonstrated that both inspiratory time (n = 8, r = 0.78, p < 0.001, 95%CI: 0.47–0.92) and volume (n = 8, r = 0.58, p = 0.0186, 95%CI: 0.15–0.85) strongly correlate with pulmonary deposition of inhaled drugs.

Assessing of low-tech solutions for aerosol delivery: Comparative performance study of manufactured versus homemade spacers

PurposeThis study aims to evaluate the performance of low-cost homemade spacers compared with manufactured valved holding chambers (VHCs) for fluticasone propionate delivery via a pMDI (pressurized Metered Dose Inhaler). MethodsThe Total Emitted Dose (TED) and particle size distribution were measured for pMDI alone or connected to the different spacers, according to CAN/CSA-Z264.1-02 standard. Two types of low-cost alternative and manufactured spacers were investigated: 500 mL plastic bottle and 553 mL aluminium can; non-antistatic plastic VHCs and aluminium antistatic VHCs. ResultsThe TED of homemade plastic bottle vs plastic VHC were similar in the 20–23% range. In contrast, the TED of homemade aluminium can was higher compared to aluminium VHC (83% vs 68%). The Fine Particle Fraction (FPF) was similar for the two plastic-based spacers (in the 12.68–17.60% range), although it was greater for the aluminium can compared to aluminium VHC (51% vs 42%). However, all spacers have limited large particles fraction, mainly deposited in the oropharyngeal tract, potentially decreasing side effects. ConclusionWe demonstrated that low-tech solutions as homemade spacers have at least similar performances to VHC medical devices composed of same material (aluminium or plastic). Thus, low-cost homemade spacers represent alternatives in case of emergency and without VHCs nearby.

Influence of the valve on the performance of two cylindrical valved holding chambers

The use of valved holding chambers (VHCs) is recommended when pressurized metered dose inhalers (pMDI) are prescribed. These medical devices decrease actuation-inhalation coordination difficulties, improve drug delivery and reduce oropharyngeal deposition. In this work, an in vitro and in silico analysis of two commercial VHCs is performed. Both devices are antistatic and are similar in length, volume, shape, but have different valve design (valve seat and flaps). Experimental results, using a Next Generation Impactor, showed that the VHCs differ in their performance, so they are not interchangeable. However, when flaps are not present in commercial VHCs and its 3D prototypes (designed with the same body volume and wall material), the differences in emitted fraction are not significant. In addition, studies performed with computational fluid dynamics showed that the highest particle deposition occurs by impact on the valve. Thus, while multiple factors of VHCs influence the delivered dose, in this work it has been shown that the main one to be considered is the valve design. • An in vitro and in silico analysis of two commercial VHCs is performed. • VHCs are not interchangeable when used with valve flaps. • The differences in emitted fraction are not significant when the flaps are removed. • CFD studies show that the highest particle deposition occurs by impact on the valve. • It has been shown that the main factor to be considered is the valve design.

Does Valved Holding Chamber Improve Aerosol Lung Deposition with a Jet Nebulizer? A Randomized Crossover Study.

Using valved holding chambers (VHC) during aerosol therapy has been reported to improve the inhaled dose with various aerosol devices, including vibrating mesh nebulizers. The aim of this study was to quantify the pulmonary deposition of a jet nebulizer (JN) with and without a VHC, and a mesh nebulizer (MN) with a VHC in a randomized cross-over trial with seven healthy consenting adults. Our hypothesis was that the use of a VHC would improve deposition with the JN. Diethylnitriaminopentacetic acid with technetium (DTPA-Tc99m), with the activity of 1 mC with 0.9% saline solution was nebulized. The radiolabeled aerosol was detected by 2D planar scintigraphy after administration. The pulmonary deposition was greater with a JN with a VHC (4.5%) than a JN alone (3.2%; p = 0.005. However, an MN with a VHC (30.0%) was six-fold greater than a JN or JN with a VHC (p < 0.001). The extrapulmonary deposition was higher in the JN group without a VHC than in the other two modalities (p < 0.001). Deposition in the device was greater with a JN + VHC than an MN+/VHC (p < 0.001). Lower residual drug at the end of the dose was detected with an MN than either JN configuration. The exhaled dose was greater with a JN alone than either an MN or JN with VHC (p < 0.001). In conclusion, the addition of the VHC did not substantially improve the efficiency of aerosol lung deposition over a JN alone.

DRUG DELIVERY EVALUATION OF A NEW VALVED HOLDING CHAMBER DESIGNED SPECIFICALLY FOR ON-THE-GO USE

TOPIC: Pharmacotherapeutics TYPE: Original Investigations Valved Holding Chambers/spacers are commonly prescribed for patients to aid coordination of their MDI and optimize medication delivery to the lungs while filtering out the larger particles that would otherwise deposit in the back of the throat. However, many patients do not use valved holding chambers (VHCs) for their MDI medication when on-the-go due to portability and appearance. This laboratory study evaluated the medication delivery performance when using a LABA (Formoterol) containing combination MDI with and without a new portable VHC (AeroChamber2go*, A2Go) designed specifically for on-the-go usage. DISCLOSURES: no disclosure on file for Rubina Ali; No relevant relationships by Cathy Doyle, source=Web Response Employee relationship with Trudell Medical International Please note: 27 years Added 04/13/2021 by Mark Nagel, source=Web Response, value=Salary Employee relationship with Trudell Medical International Please note: >$100000 by Jason Suggett, source=Web Response, value=Salary

Effects of Shake-Actuation Delay on Delivered Dose and Aerosol Characteristics of an Albuterol Suspension From a Pressurized Metered-Dose Inhaler.

Suspensions delivered via a pressurized metered-dose inhaler (pMDI) require shaking the canister before actuation to prevent drug sedimentation. We hypothesized that a shake-actuation delay of an albuterol hydrofluoroalkane (HFA) pMDI will increase and decrease delivered dose (DOSE) at the beginning and end of the canister's life, respectively, and that aerosol characteristics will remain unchanged with the delay. Albuterol HFA pMDIs (90 µg/actuation, 200 doses) operated with and without a 30-s shake-actuation delay, and with and without a valved holding chamber (VHC), were studied. Ten puffs, with a 30-s interval between puffs and 5s of shaking, were actuated into a drug-recovery apparatus. Inhalers were studied throughout their entire life (from 200 doses to 0 remaining doses). Particle size analysis was performed with cascade impaction at the beginning, middle, and end of the canister's life. Albuterol mass was determined via spectrophotometry (276 nm). Mean (99% CI) delivered dose without shake-actuation delay was 100.4% (98.1-102.9%) of the nominal dose. Mean (99% CI) delivered dose with a VHC without a shake-actuation delay was 48.6% (46.2-50.9%) of the nominal dose. The shake-actuation delay increased and decreased delivered dose at the beginning and end of the canister's life, respectively, irrespective of VHC use. Decline in delivered dose began when 110-120 doses remained in the canister. Aerosol characteristics remained constant throughout the canister's life except for the amount of drug captured by the impactor for the pMDI with delay and the pMDI/VHC with delay. Adding a VHC to a pMDI operated with a delay increased fine-particle fraction and decreased the amount of drug captured by the impactor at the middle and at the end of the canister's life. A 30-s shake-actuation delay of an albuterol HFA pMDI increased and decreased delivered dose at the beginning and end of canister's life, respectively. Particle size characteristics at the end of the canister's life changed when the pMDI and pMDI/VHC were operated with a shake-actuation delay. Patients should re-shake the pMDI if it is not actuated immediately after shaking the canister.

Effect of different accessory devices on the dose delivered from pressurised metred-dose inhalers.

Improved aerosol delivery of bronchodilators to chronic obstructive pulmonary disease (COPD) subjects is a cornerstone in the treatment approach. Drug delivery and response are improved with the use of accessory devices [spacers and valved holding chambers (VHCs)] with metred-dose inhalers (pMDIs). However, different accessory devices are available in the market with different properties that could affect aerosol delivery. Thus, this study aimed to assess the relative lung deposition and systemic bioavailability and compare bronchodilator response of salbutamol delivered using different accessory devices attached to pMDIs. Twelve healthy subjects and twelve COPD subjects inhaled 300 μg salbutamol (3 pMDI puffs) using five different accessory devices with either masks or mouthpieces (Able, Aerochamber plus flow Vu, Dolphin chamber, Tipshaler spacer, and modified Drink bottle spacer). Urine samples were collected thirty minutes post-dosing and cumulatively for the next twenty-four hours, to determine and compare the relative lung deposition [0-0.5 hour excretion of urinary salbutamol (USAL0.5)] and systemic bioavailability [0.5-24hours excretion of urinary salbutamol (USAL24)] of salbutamol from the selected accessory devices. Also, the difference between pre and post-inhalation forced expiratory volume in one second (ΔFEV1 %) of predicted was determined for each accessory device. Urinary excretion of salbutamol (both USAL0.5 and USAL24 samples) in COPD subjects was significantly (P<.05) lower than in healthy subjects for all accessory devices. USAL0.5 and USAL24 in non-antistatic spacers (modified Drink bottle spacer and Dolphin chamber spacers) were significantly lower (P<.05) than that for antistatic spacers (Aerochamber plus flow Vu, Able and Tips-haler). No significant difference in USAL0.5 and USAL24 was observed between facemasks and mouthpieces. There was a significant difference (P<.05) in ΔFEV1 % of predicted values between COPD subjects and healthy subjects. However, within the COPD group and the healthy group there was no significant difference in ΔFEV1 % of predicted values between all accessory devices or between with mouthpiece or with a mask. COPD subjects had lower aerosol delivered compared with healthy subjects. Anti-static accessory devices delivered a higher amount of aerosol compared with non-antistatic accessory devices. Even though the presence of a significant difference in aerosol delivery between non-antistatic and antistatic accessory devices no significant difference was found in the ΔFEV1 % between all accessory devices.

A Novel Adherence Sensor System for Valved Holding Chambers Suitable for Children and Adults With Asthma

Poor adherence to inhaled drug therapy is considered to be a major factor in asthma related morbidity and it has been shown, in a significant number of patients, that estimates of adherence by patients or parents of children is not accurate. Inaccurate reporting may lead to higher dose of drug or more potent drugs being prescribed. A number of adherence sensors are available for some commercial inhaler devices. However, existing adherence monitoring mainly focuses on how the hardware of an inhaler has been actuated and does not provide evidence of drug aerosol inhalation. Valved holding chambers are now first choice for aerosol drug delivery for young children, who inhale drug by breathing in and out of the device several times and are increasingly used by older children and adults who inhale drug aerosol by taking a single deep breath. To the best knowledge of the authors, there is no adherence sensor in the market that provides evidence of actuation of the drug into a valved holding chamber and evidence that it is inhaled by different age groups. We therefore developed a novel adherence sensor system embedded into a valved holding chambers to achieve this. Our customised algorithm ensures that correct use is recorded, and incorrect use flagged. It also distinguishes a deep breath from tidal breaths and in combination measurement of actuation into the device triggers different classifiers for registering usage as good technique or not. A good technique or poor technique is immediately fed back to users using a visual light signal, while the data recorded is Bluetoothed to a paired mobile device for historical recording and statistical analysis. The entire system, including battery, micro-controller, sensors and Bluetooth, is integrated on a 66 ×22 mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> printed circuit board and weighs only 8 grams. The system has been evaluated on a custom-made artificial lung which mimics the breathing patterns confirming recognition of tidal and deep breaths. The low-power device operates from a 3.3 V, 560 mAh battery and lasts 14 months if used daily.

Evaluation of Valved Holding Chambers Simulating Repurposing Use of Ciclesonide Metered-dose Inhaler by Patients with Pneumonia

Achieving appropriate inhalation in patients with coronavirus disease 2019 (COVID-19) is a common challenge in the use of repurposed metered-dose inhaler (MDI) formulations. The purpose of this study was to evaluate the effect of five valved holding chambers (VHCs) on the inhalation of ciclesonide from Alvesco MDI. The aerodynamic particle size distribution of ciclesonide discharged from Alvesco MDI was evaluated using a Next Generation Impactor in the presence and absence of VHCs. The use of VHCs retained or slightly increased the amount of ciclesonide in the fine particle diameter range (aerodynamic particle size below 3 μm) (FPD) and reduced the amount at the induction port after coordinated inhalation. However, the use of VHC reduced the FPD of the formulation by increasing the time between the MDI discharge and the pump suction by various degrees among the five VHCs. These results indicated that use of the VHCs and minimizing the inhalation delay time should ensure sufficient inhalation of ciclesonide particles.

Comparison of tiotropium delivery with the ODAPT adapter and a valved holding chamber

RATIONALE: Facemasks are commonly used by certain patients requiring assistance for aerosol medication delivery. Adapters are used as connectors between facemasks and inhalers. The valved holding chamber (VHC) is commonly prescribed with pressurized metered dose inhalers (pMDIs) to improve medication delivery. Recently, the VHC has been used with the Respimat Soft Mist Inhaler (SMI), which is a propellant-free inhaler. The ODAPT soft mist adapter was previously designed to serve as a connector for facemasks used with the Respimat SMI. OBJECTIVE The purpose of this in vitro study is to compare the Respimat medication delivery and losses using facemasks when connected separately to 1) the VHC and 2) the ODAPT adapter. METHODS Tiotropium was delivered via the Spiriva Respimat SMI with add-ons (either ODAPT adapter or VHC) and without add-ons under different humidity levels (40–50% and >90%) at 28.3 L/min using an 8-stage Andersen cascade impactor. The particle deposition was assessed via UV-visible spectrophotometry. MEASUREMENTS AND MAIN RESULTS: Under ambient humidity conditions, 7.39% and 19.10% loss of fine particle fraction (FPF) were found using the ODAPT adapter and VHC, respectively. However, for higher humidity, mimicking humidity levels in the lungs, a loss of medication of 16.74% and 30.20% was found using the ODAPT adapter and VHC, respectively. Significant differences were found in medication delivery using the two different connectors, where higher medication losses were found using the VHC. CONCLUSION The ODAPT adapter connected to the Respimat SMI was shown to provide higher medication deposition and to minimize drug losses.

Real-Time Analysis of the Respiratory Flow Through a Valved Holding Chamber.

Background: The ability of patients to take, correctly and regularly, aerosol treatments is a key for good control of asthma and chronic obstructive pulmonary disease. Devices that help to improve inhalation technique could train the patient to take their medication properly, reducing risk of exacerbations. In this study we evaluate a new device that by recording real-time respiratory flow into the valved holding chamber (VHC) mouthpiece, could be used to improve patient technique. Methods and Results: Using computational fluid dynamics analysis we demonstrated that compared to a mouthpiece with no flow probe, the presence of a probe modifies the flow profile and velocity regardless of the probe shape or position. During flow measurement using a SDP610 pressure sensor (Sensirion, Switzerland), all probes can accurately record adult and child respiratory patterns. Resistance was determined from the back pressure generated by the VHC with or without probes; and resistance was not impacted by the probes. Aerodynamic particle size distribution and drug delivery measurement were assessed using the United States Pharmacopeia throat model (Copley Scientific, UK), next generation impactor (NGI; Copley Scientific), and a breath simulator (BRS200; Copley Scientific). To test different formulations, these experiments were performed with fluticasone propionate (Flixotide®; GSK, UK), salbutamol (Ventolin®; GSK), and beclomethasone dipropionate (BDP) (QvarSpray®; GSK). Depending on the molecule or the probe configuration, we noticed a decrease of the emitted doses, fine particle deposition, mass median aerodynamic diameter, but no significant change in the mass of drug delivered. A decrease in the fine particle fraction (FPF) was observed in most testing conditions. However, a slight increase was noticed for two conformations with BDP (round and close [Rc] and diamond and far [Df]) and salbutamol (Rc and round and far [Rf]). Conclusion: By inserting a flow probe directly into the mouthpiece of a VHC we could perform real-time analysis of respiratory flow during the VHC use without disturbing drug delivery, or increasing resistance.

Spacers and Valved Holding Chambers—The Risk of Switching to Different Chambers

Spacers are pressurized metered-dose inhaler (pMDI) accessory devices developed to reduce problems of poor inhaler technique with pMDIs. Spacers that feature a 1-way inspiratory valve are termed valved holding chambers (VHCs); they act as aerosol reservoirs, allowing the user to actuate the pMDI device and then inhale the medication in a 2-step process that helps users overcome challenges in coordinating pMDI actuation with inhalation. Both spacers and VHCs have been shown to increase fine particle delivery to the lungs, decrease oropharyngeal deposition, and reduce corticosteroid-related side effects such as throat irritation, dysphonia, and oral candidiasis commonly seen with the use of pMDIs alone. Spacers and VHCs are not all the same,and also are not interchangeable: the performance may varyaccording to their size, shape, material of manufacture and propensity to become electrostatically charged, their mode of interface with the patient, and the presence or otherwise of valves and feedback devices. Thus, pairing of a pMDI plus a spacer or a VHC should be considered as a unique delivery system. In this Rostrum we discuss the risk potential for a patient getting switched to a spacer or VHC that delivers a reduced dose medication.

A comparison of the costs of bronchodilator delivery methods in children with asthma exacerbations treated in hospital. The first Polish study in children.

IntroductionRecommended methods of administering bronchodilator drugs in children with asthma exacerbations in a hospital include the pressurized metered-dose inhaler (pMDI) and nebulization (NEB). These methods differ in clinical effectiveness, safety and, as some studies indicate, the cost of their use in a child.AimTo calculate the direct costs of hospital therapy conducted with the use of short-acting β2-agonist (SABA) or its combination with short-acting muscarinic antagonist (SAMA) administered via pMDI with valved holding chamber (VHC) versus the same drugs in NEB in children with asthma exacerbation.Material and methodsA retrospective analysis of the costs of SABA (salbutamol) and SABA + SAMA (fenoterol + ipratropium bromide) inhalation therapy was performed. Based on the data obtained from the financial department, the pharmacy, and the sterilization department of the university hospital, the direct unit cost of the inhalation therapy in the child was calculated.ResultsThe results of the analysis indicate that in a hospital setting the cost of one-time SABA or SABA + SAMA administration via pMDI+VHC is 1.5–2.4 times lower compared to NEB. The payer incurred the lowest costs during anti-obstructive treatment using SABA with pMDI + VHC (PLN 9.39 for one inhalation procedure). The working time of medical staff during the inhalation treatment is the component generating the highest cost for the hospital (up to 40% of direct costs).ConclusionsIn hospital conditions, the supply of SABA or SABA + SAMA with the use of pMDI + VHC in a child with asthma exacerbation is more beneficial financially than the supply of the same drugs in NEB.

Antistatic treatment and salbutamol dosing have variable effect on drug delivery of valved holding chambers

AimsOur aim was to evaluate whether the number of puffs or antistatic treatment have significant effect on drug delivery of six different valved holding chambers (VHCs). MethodsWe used simulated paediatric breathing pattern with 25/min frequency and 200 ml tidal volume. When comparing the effect of antistatic treatment, we used 100 μg of salbutamol (one puff Ventolin Evohaler 100 μg/dos) actuated into each VHC before and after detergent wash. When comparing the effect of one or two puffs (100 vs. 200 μg), all VHCs were washed prior to the measurements. ResultsAll VHC were significantly affected by antistatic treatment. Washing improved drug delivery of four VHCs (1.3–2.2 fold increase in median filter dose) but had an opposite effect in two devices (54–61% decrease). The effect of dose doubling resulted in a 2.03–2.93 fold increase on filter dose in two VHCs. Four out of the six VHC showed significantly poorer performance with two puffs as opposed to one puff (ratio of two puffs to one puff varied between 1.19 and 1.77). ConclusionVHCs marketed as antistatic are significantly affected by antistatic treatment. To ensure optimal drug delivery, salbutamol should be actuated to VHCs one puff at a time. Each VHC brand has its unique characteristic that affects drug delivery in a way that cannot be generalised to another VHC. There is a need for universal standardisation of VHCs. Key notesValved holding chambers (VHCs) that are marketed as antistatic are significantly affected by antistatic treatment. Multiple actuations before inhalation tend to decrease the drug delivery efficacy of VHCs. Each VHC brand has its unique characteristic that affects drug delivery in a way that cannot be generalised to another VHC. There is a need for comprehensive and financially independent testing and standardisation of VHCs.

Inhalation technique practical skills and knowledge among physicians and nurses in two pediatric emergency settings

Introduction: Correct technique with a pressurized metered-dose inhaler (pMDI) equipped with a valved holding chamber (VHC) or spacer provides an important advantage for adequate control of asthma and virus-induced wheezing in young children. The aim of this study was to assess the ability and knowledge of physicians and nurses to use a pMDI with a masked VHC in two pediatric emergency units.Methods: Study design: Two-center observational study. Inhaler use technique was assessed in 50 physicians and 50 nurses using a child mannequin and a validated videotaped nine-step scoring method. The participants’ knowledge was evaluated by a questionnaire.Results: The inhalation technique was perfectly mastered by 49% of the study participants and almost perfectly mastered by another 34% (mean score 8.3 ± 0.7; range 5–9). Nurses were more likely than doctors to demonstrate the technique perfectly (66% vs. 32%, p < 0.05). The two most common errors were forgetting to shake the pMDI between two consecutive puffs (38% of the participants) and putting the patient in an incorrect position (11%). About half of the participants reported that they checked each patient’s inhalation technique at every opportunity and knew how to clean the VHC. A large majority did not employ a reliable method to determine the amount of medication remaining in pMDIs without a counter.Conclusion: Healthcare professionals’ practical skills and knowledge on inhalation therapy were not completely mastered and could be improved with a mandatory training program.