Type Of Nebulizer Research Articles

Comparison of the performance of inhalation nebulizer solution and suspension delivered with active and passive vibrating-mesh device

In the clinical use of nebulizers, the drug and device are sold separately and combined together when at use. Obviously, the matching of formulation and device is very important for the performance of nebulizer. In this study, the combinatorial influences of vibrating-mesh device and formulations were investigated. Two types of vibrating-mesh nebulizers (i.e. Aeroneb Pro nebulizer and Omron mircoAir NE-U22 nebulizer) and two types of inhalation liquids (i.e. albuterol inhalation solution and budesonide suspension) were used for comparison. The stabilities of drug (temperature, pH, osmolality, and concentration) were monitored during nebulization, and in vitro lung depositions of different drug-device combinations were measured under several breathing patterns. During nebulization, the properties of liquid in reservoir were overall stable by using vibrating-mesh nebulizer. In addition, the output rates of albuterol were higher than that of budesonide, and the nebulization time of the Aeroneb Pro nebulizer was shorter, but the total aerosol outputs of Omron nebulizer were higher. Furthermore, a “slow deep breathing”pattern will contribute to more drugs delivered into the lung. As the results of equivalence analysis between pharmacopeial testing and several breathing patterns, it was inferred that the existing pharmacopeial testing likely overestimates the dose reaching the pediatric lung. We conclude that in order to be an effective medication for patient, for a given formulation, a suitable device should be recommended based on specific drug composition and site of action. In addition, a multiple realistic breathing patterns rather than a single standardized adult breathing pattern should be considered in the evaluation of inhaled drug, which is neglected by current compendial method.

Size Distribution of Colistin Delivery by Different Type Nebulizers and Concentrations During Mechanical Ventilation.

Although aerosol delivery through mechanical ventilators has been used to administer various medications, little is known of administration with colistin. This in vitro evaluation aimed to evaluate size distribution of colistin delivery by different types of nebulizers and concentrations during mechanical ventilation. Colistin methanesulfonate (colistin) for injection was dissolved in 6 mL of distilled water to produce a low concentration (L; 156 mg) and a high concentration (H; 312 mg). A dose volume of 6 mL was placed in a vibrating mesh nebulizer (VMN) and a jet nebulizer (JN). The inhaled mass (mean ± SD) of the VMN-L (53.80 ± 14.79 mg) was greater than both the JN-L (19.82 ± 3.34 mg, P = 0.001) and JN-H (31.72 ± 4.48 mg, P = 0.017). The nebulization time of the VMN-L (42.35 ± 2.30 min) was two times longer than the JN-L (21.12 ± 0.8 min) or JN-H (21.65 ± 0.42 min; P < 0.001). The mass median aerodynamic distal to the endotracheal tube was within a similar range at 2.03 to 2.26 μm (P = 0.434), independent of neb or formulation concentration. In conclusion, the VMN-L yields greater inhaled mass than the JN with either concentration. Therefore, a standard nominal dose of colistin results in a higher delivered dose during mechanical ventilation with a VMN compared with a JN and may be considered the preferred device. If JN must be used, multiple doses of low concentration colistin may compensate for poor delivery performance.

Effect of nebulizer type, delivery interface, and flow rate on aerosol drug delivery to spontaneously breathing pediatric and infant lung models.

Different types of nebulizers, interfaces, and flow rates are used to deliver aerosolized medications to children. The purpose of this study was to determine the effect of nebulizer type, delivery interface, and flow rate on aerosol drug delivery to spontaneously breathing pediatric and infant lung models. A teaching mannequin was attached to a sinusoidal pump via a collecting filter at the bronchi to simulate a spontaneously breathing child (Vt: 250 mL, RR: 20 bpm and Ti: 1 second) and infant (Vt = 100 mL, RR = 30 bpm, Ti: 0.7 seconds). Albuterol sulfate was nebulized with jet (Misty Max 10; Cardinal Health) and mesh (Aerogen Solo; Aerogen) nebulizers using a low-flow nasal cannula (LFNC; Hudson), a high-flow nasal cannula (HFNC; Fisher & Paykel), face mask (FM; Hudson), and mouthpiece (MP; Cardinal Health). While all interfaces were used in the pediatric study, only LFNC, HFNC, and FM were tested in the infant study. The mesh nebulizer was tested at 2, 4, and 6 L/min with LFNC, 4 and 6 L/min with HFNC, and 6 L/min with FM and MP. The jet nebulizer was operated at 6 and 8 L/min with FM and 6 L/min with LFNC, HFNC, and MP (n = 5). The drug was eluted from the filter and analyzed by spectrophotometry. Factorial analysis of variance and post hoc comparisons were used for data analysis. P < .05 was considered statistically significant. Delivery efficiency of mesh nebulizers is two to fourfold more than jet nebulizers used with HFNC, FM, and MP. No statistical difference was found between jet and mesh nebulizers used with LFNC in infants (P = .643) and pediatrics (P = .255). Aerosol delivery with MP was the best compared to other interfaces used in pediatrics (P < .05). As the second-best interface in aerosol drug delivery, the delivery efficiency of FM was greater than HFNC (P = .0001) and LFNC (P = .0001). Increasing flow rate with LFNC and HFNC decreased aerosol delivery with the mesh nebulizer in both infants and pediatrics. The type of nebulizer, delivery interface, and flow rate used in the treatment of children affect aerosol drug delivery.

Nebuliser cleaning and disinfection practice in the home among patients with cystic fibrosis.

Nebulised delivery of different classes of drugs is of fundamental importance in therapeutic regimens relating to both the management of disease progression in cystic fibrosis disease and its associated complications. The aim of this study was to determine if current nebuliser hygiene practices in the home environment by paediatric and adult cystic fibrosis populations are appropriate to ensure appropriate infection control and prevention measures have been addressed. An Audit Questionnaire Study was completed with adult cystic fibrosis patients (n=20) or with parents of cystic fibrosis children (n=24), through a healthcare professional interview on a one-to-one basis, during either a home visit or during patient/parent attendance at cystic fibrosis clinic. Hygienic practices relating to nebuliser care varied, with paediatric carers more likely to clean and disinfect their devices. This study suggests there is much variation and confusion with regard to how to clean and disinfect nebulisers, as well as who is responsible for delivering this advice. The adult cystic fibrosis community in particular needs to be educated on practicalities associated with nebuliser hygiene and the reasons why this is important. Furthermore, to date there is a lack of a universally recommended guideline suitable for all types of cystic fibrosis nebulisers that all relevant pharmaceutical manufacturers advocate.

Fabrication of an Ultrasonic Nebulizer: Rate of Flow and Performance Studies

ABSTRACTThis article describes how to build, in-house, a new type of ultrasonic nebulizer and presents the results of tests to determine its rate of aqueous flow and its performance during the transport of a collagen-based adhesive (ratio of adhesive actually delivered to adhesive misted). It also reports on a consolidation treatment case study carried out with the new ultrasonic misting prototype: the NebulA-MG 14. This case study was applied to powdery paint layers of a medium-sized oil painting on canvas, 111.5 × 86.5 cm. The new device is shown to be both reliable and effective, particularly for consolidating medium and large-sized works.

Comparison of Salbutamol Delivery Efficiency for Jet versus Mesh Nebulizer Using Mice.

Recent reports using a breathing simulator system have suggested that mesh nebulizers provide more effective medication delivery than jet nebulizers. In this study, the performances of jet and mesh nebulizers were evaluated by comparing their aerosol drug delivery efficiencies in mice. We compared four home nebulizers: two jet nebulizers (PARI BOY SX with red and blue nozzles), a static mesh nebulizer (NE-U22), and a vibrating mesh nebulizer (NE-SM1). After mice were exposed to salbutamol aerosol, the levels of salbutamol in serum and lung were estimated by enzyme linked immunoassay (ELISA). The residual volume of salbutamol was the largest at 34.6% in PARI BOY SX, while the values for NE-U22 and NE-SM1 mesh nebulizers were each less than 1%. The salbutamol delivery efficiencies of NE-U22 and NE-SM1 were higher than that of PARI BOY SX, as the total delivered amounts of lung and serum were 39.9% and 141.7% as compared to PARI BOY SX, respectively. The delivery efficiency of the mesh nebulizer was better than that of the jet nebulizer. Although the jet nebulizer can generate smaller aerosol particles than the mesh nebulizer used in this study, the output rate of the jet nebulizer is low, resulting in lower salbutamol delivery efficiency. Therefore, clinical validation of the drug delivery efficiency according to nebulizer type is necessary to avoid overdose and reduced drug wastage.

Size distributions of droplets produced by ultrasonic nebulizers

In many applications where small, similar-sized droplets are needed, ultrasonic nebulizers are employed. Little is known about the mechanism of nebulization, for example about what determines the median droplet size. Even less understood, is the droplet size distribution, which is often simply fitted with a log-normal distribution or assumed to be very narrow. We perform the first systematic study of droplet size distributions for different nebulizer technologies, showing that these distributions can be very well fitted with distributions found for sprays, where the size distribution is completely determined by the corrugation of ligaments and the distribution of ligament sizes. In our case, breakup is believed to be due to pinch-off of Faraday instabilities. The droplet size distribution is then set by the distribution of wavelengths of the standing capillary waves and the roughness of the pinch-off ligaments. We show that different nebulizer technologies produce different size distributions, which we relate to (variation in) wavelengths of the waves that contribute to the droplet formation. We further show that the median droplet size scales with the capillary wavelength, with a proportionality constant that depends only slightly on the type of nebulizer, despite order-of-magnitude differences in other parameters.

Comparison of aerosol delivery across combinations of drug delivery interfaces with and without concurrent high-flow nasal therapy

BackgroundCurrent clinical practice during high-flow nasal therapy (HFNT) involves utilization of a nasal cannula to provide humidification, with a facemask placed over the cannula to deliver aerosol. Few studies have compared aerosol delivery across various delivery interfaces during HFNT. The objective of this study was to address this gap in the literature and evaluate aerosol delivery using two nebulizer types across different drug delivery interfaces, nasal cannula, facemask, and mouthpiece, during simulated adult HFNT.MethodsA facemask or mouthpiece and/or a nasal cannula were positioned on an anatomically correct adult head model. The head model was connected to a breathing simulator via a collection filter. Both healthy breathing pattern and distressed breathing patterns were utilized. Aerosol dose was determined by quantifying the mass of drug captured on a filter positioned distal to the trachea.ResultsDuring simulated healthy breathing, a significantly greater aerosol dose was observed when the vibrating mesh nebulizer (VMN) was integrated with HFNT alone, supplying aerosol and humidified air simultaneously (2.88 ± 0.15%), as opposed to using with a facemask (0.33 ± 0.07%, 1.62 ± 0.46%, and 1.07 ± 0.25% at 0 L/min (LPM), 2LPM, and 6LPM, respectively) or mouthpiece (0.56 ± 0.13%, 2.16 ± 0.06%, and 1.82 ± 0.41% at 0LPM, 2LPM, and 6LPM). In addition, aerosol delivery was also significantly greater when the VMN was integrated into simulated HFNT (2.88 ± 0.15%), in comparison with using the jet nebulizer (JN) with a facemask (0.82 ± 0.16%) or a mouthpiece (0.86 ± 0.11%). During simulated distressed breathing, a significantly greater aerosol dose was observed when the VMN was integrated with HFNT, supplying aerosol and humidified air simultaneously (6.81 ± 0.45%), compared with using a facemask (0.86 ± 0.04%, 2.96 ± 0.26%, and 4.23 ± 0.93% at 0LPM, 2LPM, and 6LPM) or mouthpiece (0.73 ± 0.37%, 0.97 ± 0.20%, and 3.11 ± 0.53% at 0LPM, 2LPM, and 6LPM, respectively). Aerosol delivery was also greater when the VMN was integrated into HFNT (6.81 ± 0.45%), in comparison with using the JN with a facemask (5.72 ± 0.71%) or a mouthpiece (0.69 ± 0.53%). Furthermore, across all drug delivery interfaces, and in line with previous reports, aerosol delivery was greater during simulated distressed breathing, in comparison with simulated healthy adult breathing.ConclusionsThis article will be of considerable benefit in enhancing the understanding of aerosol delivery during HFNT, an increasingly adopted therapeutic intervention by healthcare professionals.

Effects of flow pattern, device and formulation on particle size distribution of nebulized aerosol

The evaluation of particle size recommended in the pharmacopeias requires a constant flow rate, and the method for pediatric inhaled drugs is the same as for adult drugs. In this study, the aerosol concentration and particle size distribution (PSD) were measured under a realistic breathing pattern and constant flow. Two types of nebulizer (i.e., breath-enhanced nebulizer and vibrating-mesh nebulizer) and two formulations (i.e., budesonide suspension and albuterol solution) were chosen for comparison. The aerosol concentration under the realistic pattern was not constant, which was different from the result at constant flow. The changing trend of aerosol concentration varied with the operation process of each device. The aerosol concentration profile was similar between budesonide suspension and albuterol solution. As to the PSD, as inspiratory flow increased, the X50 (50% undersize) increased with all nebulizers but Omron microAir NE-U22 nebulizer. There was good agreement between X50 obtained under the realistic inhalation patterns and their equivalent average flow rates by Bland-Altman analysis, although the X50 obtained under the realistic inhalation pattern was greater than value at constant flow. The agreement of the two breath-enhanced jet nebulizers was better than that of the vibrating-mesh nebulizers. The X50 of budesonide was not equal to that of albuterol when using the same nebulizer. Interestingly, a significant difference was observed in the X50 and Span when comparing the results of PSD under adult and child breathing patterns. Furthermore, all vibrating-mesh nebulizers produced aerosol droplets having larger mean diameter and narrower size distribution than those of the air-jet nebulizers. We conclude that it will be more conducive to the evaluation of particle size to use a laser diffractometer under a realistic pattern and make up for the shortcomings of cascade impactors. The effects of flow pattern, nebulizer and formulation should be taken into account in the evaluation of the qualities of nebulizer products in pharmaceutical practice.

Nebulized therapy in children

Nebulization is widely used in treating respiratory disorders in younger patients and critically ill children.Jet nebulizers, ultrasonic nebulizers and vibrating mesh nebulizers are the main types of small volume nebulizers used in emergency room and pediatric intensive care unit.Glucocorticoids, bronchodilators, mucolytic agents can be administered via nebulization.Different compatibilities exist among these therapeutic agents. Key words: Child; Nebulization; Small volume nebulizer; Nebulizable drug

Nebulization effects on structural stability of bacteriophage PEV 44

Reduced infectivity of phage due to the nebulization process has been reported previously, but no visual evidence on structural change upon nebulization has been established, or whether these structural changes can be attributed to the titer reduction. In this study, transmission electron microscopy (TEM) was employed to assess the impact of three different types of nebulizers, air-jet, vibrating-mesh and static-mesh nebulizers, on the structural stability of a Myoviridae phage, PEV44, active against Pseudomonas aeruginosa. The morphology of the phage in the nebulized samples was categorized into two groups: “whole” (the capsid and tail held together) and “broken” (the capsid separated from the tail) phages. The “whole” phage group was further divided into three sub-groups: (1) intact, (2) contracted tail and (3) empty capsid. The starting stock suspension was found to contain considerable portions of “broken” phages (35.5 ± 6.7%), “whole” phages with contracted tails (9.9 ± 5.4%) and empty capsids (19.3 ± 8.9%). The fraction of “broken” phages was significantly increased after nebulization, with the air-jet nebulizer (83%) being more pronounced than the mesh type nebulizers (50–60%). While the amount of intact phages (2–10%) and whole phages with contracted tails (0–3%) were significantly decreased, the proportion of phages with empty capsids (15–36%) were not significantly different. Phages with broken features obtained by TEM quantification were 92.9 ± 3.2%, 74.8 ± 10.4% and 71.2 ± 11.0% for the jet, vibrating-mesh and static-mesh nebulizers, respectively. These results were found to be comparable with the titer loss obtained by the conventional plaque assay results. The in vitro aerosol performance and viable phage delivery of the three nebulizers was also assessed. The Omron nebulizer achieved a significantly higher viable respirable fraction (VRF) than the SideStream and Aeroneb Go (15.1 ± 5.8%, 2.4 ± 2.0%, 4.1 ± 2.7% respectively). In conclusion, this study identified various changes in the phage structure and viability of phage from different types of nebulizers. Understanding these effects and the phage tolerance to nebulization stresses can potentially improve our choice of the delivery method for inhaled phage therapy.

Inhalers and nebulizers: basic principles and preliminary measurements

Inhalers are hand-held devices which are used for administration of therapeutic aerosols via inhalation. Nebulizers are larger devices serving for home and hospital care using inhaled medication. This contribution describes the basic principles of dispersion of aerosol particles used in various types of inhalers and nebulizers, and lists the basic physical mechanisms contributing to the deposition of inhaled particles in the human airways. The second part of this article presents experimental setup, methodology and preliminary results of particle size distributions produced by several selected inhalers and nebulizers.

Vibrating Mesh Nebulisers – Can Greater Drug Delivery to the Airways and Lungs Improve Respiratory Outcomes?

Aerosols are an increasingly important mode of delivery of drugs, particularly bronchodilators, for the treatment of respiratory diseases, notably asthma and chronic obstructive pulmonary disease. The most common type of nebuliser is the jet nebuliser (JN); they have been in use for more than a century but these devices can be cumbersome to use and may sometimes deliver insufficient amounts of drug. A more recent development in aerosol therapy is the vibrating mesh nebuliser (VMN) which is very user friendly and is more efficient than the JNs due to an extremely low residual volume. Scintigraphy images from studies of volunteer subjects using radio-labelled aerosol treatment show that VMN-generated aerosols deliver more drug to patients in a shorter period of time than JN-generated aerosols. Various bench, animal model and small clinical studies have shown that VMNs are more efficient than JNs in drug delivery, potentially improving clinical outcomes. These studies have included various breathing circuits used in mechanical ventilation (MV), non-invasive ventilation, high-flow nasal cannula systems and devices for spontaneously breathing patients. The efficiency of drug delivery was affected by factors including the position of the nebuliser in the circuit and humidity. Some studies have shown potential substantial savings by hospitals in the cost of MV treatments after switching from metered dose inhalers to VMNs. VMNs have also been shown to be effective for the administration of inhaled antibiotics, corticosteroids and other drugs. Larger studies of the effects of VMNs on patient outcomes are needed but they are likely to be an increasingly important means of administering therapies to a burgeoning population with respiratory disease.

Aerosol delivery during spontaneous breathing with different types of nebulizers- in vitro/ex vivo models evaluation

BackgroundNebulizers for spontaneous breathing have been evaluated through different study designs. There are limitations in simulated bench models related to patient and nebulizer factors. The aim of this study was to determine the correlation of inhaled drug mass between in vitro and ex vivo studies by testing aerosol deposition of various types of nebulizers. MethodsTen healthy subjects were recruited to receive aerosol therapy with five nebulizers in random order: 1) a jet nebulizer (JN); 2) a breath-enhanced nebulizer (BEN); 3) a manually triggered nebulizer (MTN), 4) a breath-actuated nebulizer (BAN), and 5) a vibrating mesh nebulizer (VMN) with valved-adapter. A unit dose of salbutamol containing 5 mg in 2.5 mL was placed into the nebulizer and administered for 10 min. For the ex vivo study, minute ventilation of healthy subjects was recorded for 1 min. For the in vitro study a breathing simulator was utilized with adult breathing patterns. Aerosolized drug from the nebulizers and the accessory tubes was captured using inspiratory and expiratory collecting filters. Captured drug was eluted, measured and expressed as inhaled and exhaled mass using spectrophotometry at a wavelength of 276 nm. Results10 healthy subjects were recruited, aged 20.8 ± 0.7 years old, with a mean height of 166.2 ± 9.2 cm and weight of 64.7 ± 12.4 kg. There was no significant difference in the inhaled drug dose between the JN and BEN (15.0 ± 1.94% and 17.74 ± 2.65%, respectively, p = .763), yet the inhaled doses were lower than the other three nebulizers (p < .001). The VMN delivered greater inhaled dose than the other four nebulizers (p < .01). The respiratory rate of the cohorts was significantly correlated with the inhaled drug dose. For the in vitro model, the JN delivered a lower inhaled dose (11.6 ± 1.6, p < .001) than the other nebulizers, whereas the MTN and BAN deposited significantly lower exhaled doses (1.7 ± 0.4 and 2.7 ± 0.2, respectively, p < .001). The VMN demonstrated a greater drug dose with the in vitro study than the ex vivo model (44.0 ± 0.9% and 35.5 ± 6.3% respectively, p = .003), whereas the JN in the ex vivo model resulted in a greater inhaled drug dose (15.0 ± 1.9% for ex vivo vs 11.6 ± 1.6% for in vitro, p = .008). ConclusionsThese in vitro/ex vivo model comparisons of nebulizers performance indicated that breath-related nebulizers can be estimated using an in vitro model; however, the JN and VMN delivered inhaled drug mass differed between models. There was a significant correlation between respiratory rate and inhaled mass, and the inhaled drug dose generated by VMN correlated with minute ventilation. This study demonstrated that the VMN produced greater inhaled drug dose and lowest residual dose, whereas the BEN, BAN, and MTN produced lower exhaled drug dose in both in vitro and ex vivo models.

Albuterol Delivery Efficiency in a Pediatric Model of Noninvasive Ventilation With Double-Limb Circuit.

Noninvasive ventilation (NIV) is used to treat respiratory failure in patients with concomitant need for aerosol delivery. Limited pediatric data are available on aerosol delivery efficiency, and none at all regarding aerosol delivery efficiency with a double-limb circuit. We compared the effect of position in the double-limb ventilator circuit, types of nebulizer, and ventilator settings on aerosol delivery efficiency in a pediatric model of NIV. We hypothesized that placing a vibrating mesh nebulizer at the ventilator and using the highest inspiratory pressures would increase aerosol delivery efficiency. A breathing simulator was connected in series to a low dead-space filter holder (lung dose) and to an anatomically correct head/airway model of a 5-year-old child. A non-vented mask connected the model to a ventilator operated on noninvasive bi-level mode and assembled with a double-limb, heated-wired adult circuit. Inspiratory pressures of either 15 or 20 cm H2O and an expiratory pressure of 5 cm H2O were used. Two different vibrating mesh nebulizers and 2 different jet nebulizers loaded with albuterol solution were studied. Albuterol was measured with spectrophotometry. Aerosol delivery efficiency was calculated as lung dose expressed as a percentage of the nominal dose. A vibrating mesh nebulizer before the mask or Y-piece provided the highest delivery efficiency and outperformed a vibrating mesh nebulizer integrated into the mask. Vibrating mesh nebulizers delivered more drug than jet nebulizers, regardless of their position in the circuit. Increasing the inspiratory pressure only improved aerosol delivery efficiency with a jet nebulizer placed at the ventilator. In a pediatric model of NIV, the effect of nebulizer position on aerosol delivery efficiency depends on the type of device and its placement in the ventilator circuit. A vibrating mesh nebulizer placed at the mask or before the Y-piece of the double-limb circuit provided the highest aerosol drug delivery during NIV. Data generated with invasive ventilation models should not be generalized to NIV models.

Early Halt of a Randomized Controlled Study with 3% Hypertonic Saline in Acute Bronchiolitis

Background: Albeit not recommended because of contradictory results, nebulized 3% hypertonic saline is widely used for treating acute viral bronchiolitis. Whether clinical differences may be attributed to the type of nebulizer used has never been studied. Objectives: By modifying the amount of salt deposited into the airways, the nebulizer characteristics might influence clinical response. Methods: A prospective, randomized, controlled trial included infants hospitalized in a French university hospital for a first episode of bronchiolitis. Each child received 6 nebulizations of 3% hypertonic saline during 48 h delivered with 1 of the 3 following nebulizers: 2 jet nebulizers delivering large or small particles, with a low aerosol output, and 1 mesh nebulizer delivering small particles, with a high aerosol output. The primary endpoint was the difference in the Wang score at 48 h. Results: Only 61 children of 168 were recruited before stopping this study because of severe adverse events (n = 4) or parental requests for discontinuation due to discomfort to their child during nebulization (n = 2). One minor adverse event was noted in 91.8% (n = 56/61) of children. A high aerosol output induced 75% of the severe adverse events; it was significantly associated with the nebulization-induced cough between 24 and 48 h (p = 0.036). Decreases in Wang scores were not significantly different between the groups at 48 h, 9 recoveries out of 10 being obtained with small particles. Conclusion: No beneficial effects and possibly severe adverse events are observed with 3% hypertonic saline in the treatment of bronchiolitis.

Conspectus Of Nebulizers

Nebulization or atomization is a technique of transforming liquid into a fine mist and the machine used for this particular purpose is called a nebulizer. Generally nebulizers can be sorted into jet, ultrasound and mesh which are classified on the basis of the method of production of aerosols from liquid. Various factors such as distal drug deposition on the face and mask, median aerodynamic diameter, remaining drug after nebulizing and nebulization time, determine the extent of performance and its efficiency. All the three kinds of nebulizers have different properties this paper will focus on the nebulizer types, their performance and uses in the medical field.

Principle and influence factors of aerosolized antibiotics in the treatment of ventilator associated pneumonia

Ventilator associated pneumonia (VAP) is a challenging complication of critical illness. Aerosolized antibiotic is an option for the management of VAP currently, as it is reported that it could increase levels of drug in alveolar without increasing systemic toxicity. The articles that focused on the aerosolized antibiotics in the treatment of VAP and its influence factors were reviewed, and it was found that to achieve maximum drug delivery efficiency and reduce the influence of nebulization method, some factors, such as ventilation modes, tidal volume, nebulizer type, should be adjusted and monitored during the treatment.

Modelling of in-vitro and in-vivo performance of aerosol emitted from different vibrating mesh nebulisers in non-invasive ventilation circuit

Substituting nebulisers by another in non-invasive ventilation circuit (NIV) involves many process variables which must be adjusted to ensure patient optimum therapy. However, there is a doubt when nebulisers use the same technology.Data mining technology based on artificial neural networks and genetic algorithms were used here to model in-vitro inhalation process and predict bioavailability from inhaled doses delivered by three different vibrating mesh nebulisers (VMNs) in NIV.Modelling of data indicated that in-vitro performance of VMNs was dependent mainly on fine particle fraction, mass median aerodynamic diameter (MMAD), total emitted dose (TED) and to lesser extent on nebuliser type.Ex-vivo model indicated that amount of salbutamol collected on facemask filter was directly affected by TED. In-vivo model showed that amount of salbutamol deposited into the lung (0.5hQ) and amount absorbed systemically (24hQ) were dependent directly on MMAD and TED. Female patients showed higher 24hQ values than males. Nebuliser type affected TED, 0.5hQ but not 24hQ values.Results indicate suitability of VMNs in achieving appropriate in-vitro inhalation performance model. The results also, indicate that the three VMNs are comparable and can be interchanged with no fear of any additional toxicity.

Inhalation Antibiotics in Ventilator-associated Pneumonia (VAP): Drugs, Devices, and Evidence

Ventilator-associated pneumonia (VAP) is still one of the most frequent nosocomial infections. It is associated with a prolonged intensive care unit and hospital stay, high mortality rates, and additional health care costs. Despite the availability of modern intensive care unit care and antibiotics, the overall clinical cure rate for VAP in randomized clinical trials is low, especially in the presence of multidrug-resistant gram-negative pathogens. Therefore, many clinicians explore the use of inhalation antibiotics in the treatment of VAP. This review focuses on the currently available inhalation antibiotics for VAP and different types of nebulizers for the administration of antibiotics.