Aerosol Therapy Research Articles

The efficacy and safety of aerosol therapy in rhinology

Abstract Aerosol drug administration has a long history as an important part of the treatment for different respiratory disorders in both adult and paediatric patients. The nebulization process permits the drug delivery directly to the upper and lower airways tracts, allowing increased local effectiveness, and avoids systemic side effects. The aerosol therapy is mainly used in pneumology for lower respiratory tract disorders, a series of drugs having a proven efficacy. Few publications present the efficacy and safety of ENT nebulization, despite its worldwide utilization. Topical drug delivery to the nasal cavities and paranasal sinuses via aerosols appears to be an interesting, but also a challenging alternative. The transport and deposition of drugs and aerosol particles into the sinuses is debatable due to several factors: sinuses are poorly perfused and virtually non-ventilated cavities; they are protected by the efficient particle filtration function of the nasal cavities. The review evaluates the efficacy and safety of aerosol therapy in rhinologic pathology.

Targeted delivery of flagellin by nebulization offers optimized respiratory immunity and defense against pneumococcal pneumonia.

Novel therapeutic strategies are urgently needed to combat pneumonia caused by Streptococcus pneumoniae strains resistant to standard-of-care antibiotics. Previous studies have shown that targeted stimulation of lung innate immune defenses through intranasal administration of the Toll-like receptor 5 agonist flagellin improves the treatment of pneumonia when combined with antibiotics. To promote translation to the clinic application, this study assessed the direct delivery of flagellin to the airways through nebulization using a vibrating mesh nebulizer in mice. Intranasal delivery achieved approximately 40% lung deposition of the administered flagellin dose, whereas nebulization yielded less than 1%. Despite these differences, nebulized flagellin induced transient activation of lung innate immunity characterized by cytokine/chemokine production and neutrophil infiltration into airways analogous to intranasal administration. Furthermore, inhalation by nebulization resulted in an accelerated resolution of systemic pro-inflammatory responses. Lastly, adjunct therapy combining nebulized flagellin and amoxicillin proved effective against antibiotic-resistant pneumococcal pneumonia in mice. We posit that flagellin aerosol therapy represents a safe and promising approach to address bacterial pneumonia within the context of antimicrobial resistance.

High-Flow Nasal Aerosol Therapy; Regional Aerosol Deposition and Airway Responsiveness.

Introduction: In normal subjects, during tidal breathing, aerosols deposit by settling in small airways. With obstructive lung disease (OLD), collapse of airways during expiration causes turbulence and increased deposition in central airways. High-flow nasal cannula (HFNC) therapy, washing out dead space, may affect deposition mechanisms and drug delivery. This study compared aerosol deposition and airway responsiveness in OLD after traditional and HFNC nebulization therapy. Methods: Twelve subjects with moderate to severe OLD participated in a two-day study. Spirometry was measured pre- and post-aerosol inhalation. On Day 1 (D1) subjects tidally inhaled radiolabeled albuterol (99mTc DTPA) by mouth via AeroTech II, (Biodex. Shirley, NY). Day 2 (D2) inhalation was via HFNC using i-AIRE (InspiRx, Inc. Somerset, NJ). The HFNC system (60 L/m) was infused by syringe pump at 50 mL/h. D2 lung deposition was monitored in real time by gamma camera to match D1. Pre and post heart rate, O2 sat, and nasopharyngeal deposition (NP) were measured. Mechanistic contributions were modeled using multiple linear regression (MLR) of deposition rate (DR µg/m) as a function of breathing frequency, airway geometry (FEV1), and parenchymal integrity (DLCO). Results: Albuterol lung depositions were matched (p = 0.13) with D1 central/peripheral (sC/P) ratios 1.99 ± 0.98. Following HFNC, peripheral deposition increased (31% ± 33%, sC/P = 1.51 ± 0.43, p = 0.01). D2/D1% change FVC increased by 16.1 ± 16.7% (p = 0.003). NP deposition averaged 333% of lung. Heart rate and O2 sat were unaffected (p = 0.31, p = 0.63 respectively). DR analysis was markedly different between D1 (R2 = 0.82) and D2 (R2 = 0.12). Conclusion: In subjects with OLD, HFNC nebulization at 60 L/min was well tolerated and increased peripheral drug delivery. Spirometry significantly improved. Systemic effects were undetected indicating limited nasal absorption. MLR demonstrated that different mechanisms of deposition govern traditional vs HFNC aerosol delivery. Breath-enhanced nebulization via HFNC may provide controllable and effective aerosol therapy in OLD.

A new aerosol delivery approach for enhanced long-term respiratory care in resource-poor settings

Continuous aerosol therapy is safe, superior, and the mainstay in the therapy of patients with severe asthma, cystic fibrosis, chronic obstructive pulmonary disease (COPD), and coronavirus disease (COVID-19). However, continuous nebulization has been perceived as highly expensive and labor-intensive, which often requires specialized medical equipment. Moreover, it is difficult to maintain consistent aerosol output and particle size delivery over an extended period without operator intervention. This work proposes a simple and reliable continuous nebulization method using a conventional gas jet nebulizer and intravenous (IV) bottle/bag. The present work reports detailed experimental studies on a gas jet nebulizer with Particle image velocimetry (PIV), Particle/droplet Imaging Analysis (PDIA), and Mie scattering techniques to demonstrate the feasibility of the proposed technique. The preliminary investigation shows that the proposed method provides continuous liquid output delivery without external supervision. The liquid delivery rate and mass median diameter (MMD) of the nebulizer mainly depend on the gas flow rate and suction height. The MMD of the primary generated droplets is reported to vary between 100 and 230 μm for a ± 10 cm suction height and 500–1000 mlph nebulization gas flow rate. Most importantly, the nebulizer spray angle, stability, droplet size distribution, and the axial and radial velocities of the droplets are marginally affected by the suction height. Therefore, the proposed system is a versatile, safe, and cost-effective method of continuous nebulization therapy, especially in resource-poor countries or contagious disease outbreak situations.

The effect of decoupling humidity control on aerosol drug delivery during HFNC for infants.

Aerosol therapy is commonly used during treatment with high-flow nasal cannula (HFNC) in the intensive care unit (ICU). Heated humidification inside the HFNC tubing circuit leads to unwanted condensation, which may greatly limit the efficiency of drug delivery. In this study, we aimed to investigate whether a novel humidification system, which decouples temperature and humidity control, can improve the delivered dose. In a bench study setup, fluorescein sodium solution was nebulized using a vibrating-mesh nebulizer in an infant HFNC circuit to measure the delivered dose, with a conventional versus a novel decoupled humidifier. The deposition of fluorescein inside each breathing circuit component and a final collection filter at the end of the nasal cannula was collected and quantified with a UV-vis spectrometer. Droplet sizes at different sections of the breathing circuit were measured by laser diffraction. Three air flow rates: 5, 10 and 15 L/min, and two nebulizer positions: (1) at the humidifier and (2) after the inspiratory tube, were tested. The delivered dose decreased with increasing flow rate for the conventional setup and was higher when the nebulizer was placed after the inspiratory tube. Turning off the conventional humidifier 10 minutes before and during nebulization did not improve the delivered dose. The decoupled humidifier achieved a significantly higher (p = .002) delivered dose than the conventional setup. The highest delivered dose obtained by the decoupled humidifier was 62.4% when the nebulizer was placed after the humidifier, while the highest dose obtained for the conventional humidifier was 36.3% by placing the nebulizer after the inspiratory tube. In this bench study, we found that the delivered dose for an infant HFNC nebulization setup could be improved significantly by decoupling temperature and humidity control inside the HFNC circuit, as it reduced drug deposition inside the breathing circuit.

Guardian’s knowledge and attitude towards inhaled corticosteroids aerosol therapy and medication compliance of children with wheezing diseases

BackgroundGlucocorticoids are widely used in inhalation aerosol therapy for wheezing diseases. This study aims to explore guardians’ knowledge and attitude towards inhaled corticosteroids (ICS) aerosol therapy and the medication compliance of children with wheezing diseases in China.MethodsThis cross-sectional study enrolled guardians of children with wheezing diseases at the First Hospital Affiliated to Shaoyang College between October 2022 and February 2023. A self-administered questionnaire was developed to collect demographic information of the participants and evaluate their knowledge and attitude towards ICS aerosol therapy. The 8-item Morisky Medication Adherence Scale was used to assess the medication compliance of children.ResultsA total of 506 valid questionnaires were collected. 260 (51.38%) participants were guardians of a ≤ 3-year-old child and 327 (64.62%) were children’s mothers. The knowledge, attitude, and medication compliance scores of all participants were 12.61 ± 5.78, 20.95 ± 2.37, and 4.69 ± 2.18, respectively. Multivariate logistic regression showed that knowledge scores [OR = 1.053, 95% CI (confidence interval): 1.017–1.090, P = 0.003], attitude scores (OR = 1.121, 95% CI: 1.030–1.219, P = 0.008), guardians of children aged 4–6 years (OR = 0.385, 95% CI: 0.242–0.612, P < 0.001), and grandparents of children (OR = 2.633, 95% CI: 1.104–6.275, P = 0.029) were independently associated with children’s medication compliance.ConclusionsIn conclusion, guardians of children with wheezing diseases in China had insufficient knowledge, unsatisfactory attitude, and poor medication compliance towards ICS aerosol therapy.Trial registrationRetrospectively registered.

Use of a Capsaicin Cough Challenge Test to Compare Four Different Techniques for Nebulization Delivery in Cats.

Successful aerosol therapy might rely more heavily on proper drug delivery than on the effectiveness of the medication. This study compared four techniques for nebulization delivery in cats. Tolerance rate (TR) was subjectively evaluated (1-3). Increasing capsaicin concentrations were nebulized for objective evaluation of efficiency. The positive response (PR) was considered when more than five coughs were induced. The following delivery methods were tested: flow-by (FB); face mask (FM); plastic-covered Elizabethan collar (EC); and plexiglass chamber (PC). The number of PRs (NPR) and the concentration of capsaicin that induced a PR (CCP) were statistically compared (p < 0.05). The PC method was the best tolerated (TR = 3.0 ± 0.0), followed by the FB (2.7 ± 0.5) and FM (2.6 ± 0.5). The EC was very stressful, and the test had to be suspended in four out of nine cats. The lowest CCP was found with the FM (91.8 ± 157.2 µM), followed by the FB (166.7 ± 190.9 µM), PC (242.6 ± 244.8 µM), and EC (350.0 ± 225.7 µM), with significant differences only between the FM and EC (p = 0.02). The highest NPR (8) corresponded to the FM, followed by the FB (7), the PC (5), and the EC (3), with significant differences between the FM and EC (p = 0.016). In conclusion, the capsaicin cough test induces reproducible and quantifiable cat responses. The FM is the most efficient for nebulization delivery, offering good compliance and the best quantitative results. FB nebulization is less efficient but may be practical if the FM is not tolerated. PC offers minor efficiency but may be useful for very stressed or aggressive cats. The EC presents low efficiency and compliance.

STUDY OF THE EFFECT OF THE COMBINATION OF HALOTHERAPY AND BREATHING GYMNASTICS IN CHILDREN WITH BRONCHIAL ASTHMA

Purpose. To date, there is no developed program and in-depth analysis of the complex impact of the effect of the combination of halotherapy and respiratory gymnastics in children with bronchial asthma, and the effect of its application on the disease has not been tracked. For this reason, referring to the successful results of the combined application of physiotherapeutic techniques, natural and reshaped physical factors in the recovery process in bronchial asthma in childhood, the following research goal was set: to implement the combined application of respiratory gymnastics and halotherapy for more effective rehabilitation program and optimal functional recovery in children with bronchial asthma and to track the effect of its impact. Material/Methods. The study was conducted from October 2018 to March 2020 in the city of Razgrad, Bulgaria, in the Resonance after-school training center. Results. The results show that properly conducted respiratory rehabilitation, combining the application of respiratory gymnastics and aerosol therapy, can contribute to the improvement of clinical indicators, reducing the frequency and severity of paroxysmal conditions, improving ventilation indicators, some gas parameters, physical capacity and quality of life. Conclusions. There are objective grounds for asserting that the tested physiotherapy program with an emphasis on respiratory gymnastics and halotherapy has a positive effect on the functional status of children with bronchial asthma and contributes to achieving independence in daily activities and improving their quality of life.

Update on the Efficacy of Aerosol Therapy Delivered to Obstructive Lung Disease Patients

Update on the Efficacy of Aerosol Therapy Delivered to Obstructive Lung Disease Patients

Aerosol drug therapy in critically ill patients (Aero-in-ICU study): A multicentre prospective observational cohort study.

In recent years, a significant understanding of delivering optimal aerosol therapy and the availability of various drugs and devices have led to an increase in its use in clinical practice. There are only a few studies available regarding their use in critically ill patients from a few parts of the world. We aimed to study the practice pattern of aerosol therapy in critically ill patients from Indian intensive care units (ICUs). After ethical approval, this multi-centric prospective observational study was performed over a study period of four weeks. Newly admitted adult patients considered who had an artificial airway and/or ventilation (including non-invasive). Patients were followed up for the next 14 days or until ICU discharge/death (whichever came first) for details of each aerosol therapy, including ongoing respiratory support, drug type, and aerosol-generating device. From the nine participating centers across India, 218 patients were enrolled. Of 218 enrolled patients, 72.48% received 4884 aerosols with 30.91 ± 27.15 (95%CI: 26.6-35.1) aerosols per patient over 1108 patient days. Approximately 62.7% during IMV, 30.2% during NIV, 2.3% in spontaneously breathing patients with an artificial airway during weaning, and 4.7% were given without an artificial airway after weaning or decannulation. In 59%, a single drug was used, and bronchodilators were the most frequent. The jet nebulizer was the most common, followed by the ultrasonic and vibrating mesh aerosol generator. The ventilator setting was changed in only 6.6% of the aerosol sessions with IMV and none with NIV. Aerosol therapy is frequently used with a wide variation in practices; bronchodilators are the most commonly used drugs, and jet nebulizers are the most widely used.

Nebulizers.

Nebulizers generate aerosols from liquid-based solutions and suspensions. Nebulizers are particularly well suited to delivering larger doses of medication than is practical with inhalers and are used with a broad range of liquid formulations. When the same drug is available in liquid or inhaler form, nebulizers are applicable for use with patients who will not or cannot reliably use a pressurized metered-dosed inhaler (pMDI) or dry powder inhaler (DPI) due to poor lung function, hand-breath coordination, cognitive abilities (e.g., infants, elderly) or device preference. In a nebulizer, liquid medication is placed in a reservoir and fed to an aerosol generator to produce the droplets. A series of tubes and channels direct the aerosol to the patient via an interface such as mouthpiece, mask, tent, nasal prongs or artificial airway. All nebulizers contain these basic parts, although the technology and design used can vary widely and can result in significant difference in ergonomics, directions for use, and performance. While many types of nebulizers have been described, the three categories of modern clinical nebulizers include: (1) pneumatic jet nebulizers (JN); (2) ultrasonic nebulizers (USN); and (3) vibrating mesh nebulizers (VMN). Nebulizers are also described in terms of their reservoir size. Small volume nebulizers (SVNs), most commonly used for medical aerosol therapy, can hold 5 to 20 mL of medication and may be jet, ultrasonic, or mesh nebulizers. Large volume nebulizers, typically jet or ultrasonic nebulizers, hold up to 200 mL and may be used for either bland aerosol therapy or continuous drug administration.

Performance Characterisation of the Airvo2TM Nebuliser Adapter in Combination with the Aerogen SoloTM Vibrating Mesh Nebuliser for in Line Aerosol Therapy during High Flow Nasal Oxygen Therapy.

High flow oxygen (HFO) therapy is a well-established treatment in respiratory disease. Concurrent aerosol delivery can greatly expediate their recovery. The aim of this work was to complete a comprehensive characterisation of one such HFO therapy system, the Airvo2TM, used in combination with the Aerogen SoloTM vibrating mesh nebuliser. Representative adult, infant, and paediatric head models were connected to a breathing simulator via a collection filter placed at the level of the trachea. A tracheostomy interface and nasal cannulas were used to deliver the aerosol. Cannula size and gas flow rate were varied across the full operating range recommended by the manufacturer. The tracheal and emitted doses were quantified via UV-spectrophotometry. The aerosol droplet diameter at the exit of the nares and tracheal interface was measured via cascade impaction. High gas flow rates resulted in low emitted and tracheal doses (%). Nasal cannula size had no significant effect on the tracheal dose (%) available in infant and paediatric models. Higher gas flow rates resulted in smaller aerosol droplets at the exit of the nares and tracheostomy interface. Gas flow rate was found to be the primary parameter affecting aerosol delivery. Thus, gas flow rates should be kept low and where possible, delivered using larger nasal cannulas to maximise aerosol delivery.

Riboflavin based setup as an alternative method for a preliminary screening of face mask filtration efficiency

Face masks are essential in reducing the transmission of respiratory infections and bacterial filtration efficiency, a key parameter of mask performances, requires the use of Staphylococcus aureus and specialised staff. This study aims to develop a novel method for a preliminary screening of masks or materials filtration efficiency by a green, easy and rapid setup based on the use of a riboflavin solution, a safe autofluorescent biomolecule. The proposed setup is composed of a commercial aerosol generator commonly used for aerosol therapy, custom 3D printed aerosol chamber and sample holder, a filter for downstream riboflavin detection and a vacuum pump. The filtration efficiency of four different masks was assessed using the riboflavin-based setup and the bacterial filtration efficiency (BFE). The averaged filtration efficiency values, measured with both methods, were similar but were higher for the riboflavin-based setup (about 2% for all tested samples) than bacterial filtration efficiency. Considering the good correlation, the riboflavin-based setup can be considered validated as an alternative method to bacterial filtration efficiency for masks and related materials fabrics filtration efficiency screening but This study aims to develop a novel method for a preliminary screening of masks or materials filtration efficiency by a green, easy and rapid setup based on the use of a riboflavin solution, a safe autofluorescent biomolecule, but not to replace regulation approaches. The proposed setup can be easily implemented at low price, is more rapid and eco-friendly and can be performed in chemical-physical laboratories without the needing of biosafety laboratory and specialised operators.

Aerosol Therapy With Inhalers During Mechanical Ventilation

What Is the Issue?&#x0D; &#x0D; Mechanical ventilation helps individuals breathe when they cannot do so on their own. During mechanical ventilation, aerosol therapy is used to deliver medication to the lungs of the person who is using the ventilator.&#x0D; High doses of aerosol therapy administered via metered dose inhaler for adults and older adults who are mechanically ventilated is common clinical practice. However, the reasoning behind this practice, and whether it has clinical benefits compared to no doses and standard doses, is unclear.&#x0D; &#x0D; What Did We Do?&#x0D; &#x0D; To inform decisions about high doses of aerosol therapy delivered with metered dose inhalers in adults and older adults receiving mechanical ventilation, we sought to identify and summarize literature comparing the clinical effectiveness of inhaled high doses of aerosol therapy versus no aerosol therapy. We also sought to identify and summarize literature comparing the clinical effectiveness of inhaled high doses of aerosol therapy versus standard doses.&#x0D; A research information specialist conducted a literature search of peer-reviewed and grey literature sources published between January 1, 2004, and January 25, 2024. The search was limited to English-language documents. One reviewer screened articles for inclusion based on predefined criteria, critically appraised the included study, and narratively summarized the findings.&#x0D; &#x0D; What Did We Find?&#x0D; &#x0D; We found 1 retrospective chart review that compared the clinical effectiveness of 2 different doses of inhaled high doses of aerosol therapy. The findings from this study suggest that, compared to lower doses, higher doses of salbutamol are associated with more days alive and free of acute lung injury and more days alive and free of indicators of acute respiratory distress and respiratory failure.&#x0D; We did not find any studies that compared the clinical effectiveness of inhaled high doses of aerosol therapy to no aerosol therapy for adults and older adults receiving mechanical ventilation that met inclusion criteria for our review.&#x0D; &#x0D; What Does It Mean?&#x0D; &#x0D; The available evidence with methodological limitations suggests that high doses of aerosol therapy with salbutamol may be associated with better clinical respiratory outcomes when compared to low doses in patients with acute lung injury who are mechanically ventilated. To inform future clinical practice, decision-makers may want to consider the potential risks and benefits and environmental implications of aerosol therapy, as well as implementation factors (e.g., resource needs, risk of contamination).&#x0D; Additional clinical studies would help provide a better understanding of the optimal dosage and clinical effectiveness of aerosol therapy for patients who are mechanically ventilated.&#x0D;

Salt Lake Aerosol Overview: Emissions, Chemical Composition and Health Impacts under the Changing Climate

Salt Lakes, having a salt concentration higher than that of seawater and hosting unique extremophiles, are predominantly located in drought-prone zones worldwide, accumulating diverse salts and continuously emitting salt dust or aerosols. However, knowledge on emission, chemical composition, and health impacts of Salt Lake aerosols under climate change is scarce. This review delves into the intricate dynamics of Salt Lake aerosols in the context of climate change, pointing out that, as global warming develops and weather patterns shift, Salt Lakes undergo notable changes in water levels, salinity, and overall hydrological balance, leading to a significant alteration of Salt Lake aerosols in generation and emission patterns, physicochemical characteristics, and transportation. Linked to rising temperatures and intensified evaporation, a marked increase will occur in aerosol emissions from breaking waves on the Salt Lake surface and in saline dust emission from dry lakebeds. The hygroscopic nature of these aerosols, coupled with the emission of sulfate aerosols, will impart light-scattering properties and a cooling effect. The rising temperature and wind speed; increase in extreme weather in regard to the number of events; and blooms of aquatic microorganisms, phytoplankton, and artemia salina in and around Salt Lakes, will lead to the release of more organic substances or biogenic compounds, which contribute to the alteration of saline aerosols in regard to their quantitative and chemical composition. Although the inhalation of saline aerosols from Salt Lakes and fine salt particles suspended in the air due to salt dust storms raises potential health concerns, particularly causing respiratory and cardiovascular disease and leading to eye and skin discomfort, rock salt aerosol therapy is proved to be a good treatment and rehabilitation method for the prevention and treatment of pneumoconiosis and chronic obstructive pulmonary disease (COPD). It is implied that the Salt Lake aerosols, at a certain exposure concentration, likely can delay the pathogenesis of silicosis by regulating oxidative stress and reducing interstitial fibrosis of the lungs. It emphasizes the interconnectedness of climate changes, chemical composition, and health aspects, advocating for a comprehensive and practical approach to address the challenges faced by Salt Lake aerosols in an ever-changing global climate.

Clinical Efficacy Evaluation of Salt Rock Aerosol Therapy in Patients with Chronic Obstructive Pulmonary Disease Complicated with Silicosis

Clinical Efficacy Evaluation of Salt Rock Aerosol Therapy in Patients with Chronic Obstructive Pulmonary Disease Complicated with Silicosis

Thalassotherapy as a multidirectional form of marine resources therapy

Thalassotherapy is a treatment that uses the natural gifts of the sea (climate, air, sea sand, algae, some species of sea fish, mother of pearl) and physical factors (hydrotherapy, heliotherapy, aerosol therapy, music therapy, kinesitherapy and others). It is mainly intended for people who are stressed, overtired and have sleep problems. Thalassotherapy is also used in the treatment of rheumatism, back pain, lung diseases, heart diseases and skin dermatoses, such as psoriasis or atopic dermatitis. These treatments are widely used in wellness centers as care and therapeutic treatments for problematic skin. In cosmetology, preparations of marine origin are also used in the form of masks, peeling creams intended for dry, oily, gray, mature or poorly nourished skin.

Inhaled drug delivery: a randomized study in intubated patients with healthy lungs

BackgroundThe administration technique for inhaled drug delivery during invasive ventilation remains debated. This study aimed to compare in vivo and in vitro the deposition of a radiolabeled aerosol generated through four configurations during invasive ventilation, including setups optimizing drug delivery.MethodsThirty-one intubated postoperative neurosurgery patients with healthy lungs were randomly assigned to four configurations of aerosol delivery using a vibrating-mesh nebulizer and specific ventilator settings: (1) a specific circuit for aerosol therapy (SCAT) with the nebulizer placed at 30 cm of the wye, (2) a heated-humidified circuit switched off 30 min before the nebulization or (3) left on with the nebulizer at the inlet of the heated-humidifier, (4) a conventional circuit with the nebulizer placed between the heat and moisture exchanger filter and the endotracheal tube. Aerosol deposition was analyzed using planar scintigraphy.ResultsA two to three times greater lung delivery was measured in the SCAT group, reaching 19.7% (14.0–24.5) of the nominal dose in comparison to the three other groups (p < 0.01). Around 50 to 60% of lung doses reached the outer region of both lungs in all groups. Drug doses in inner and outer lung regions were significantly increased in the SCAT group (p < 0.01), except for the outer right lung region in the fourth group due to preferential drug trickling from the endotracheal tube and the trachea to the right bronchi. Similar lung delivery was observed whether the heated humidifier was switched off or left on. Inhaled doses measured in vitro correlated with lung doses (R = 0.768, p < 0.001).ConclusionOptimizing the administration technique enables a significant increase in inhaled drug delivery to the lungs, including peripheral airways. Before adapting mechanical ventilation, studies are required to continue this optimization and to assess its impact on drug delivery and patient outcome in comparison to more usual settings.

In-Line Aerosol Therapy via Nasal Cannula during Adult and Paediatric Normal, Obstructive, and Restrictive Breathing.

High-flow nasal oxygen therapy is being increasingly adopted in intensive and home care settings. The concurrent delivery of aerosolised therapeutics allows for the targeted treatment of respiratory illnesses. This study examined in-line aerosol therapy via a nasal cannula to simulated adult and paediatric models with healthy, obstructive and restrictive lung types. The Aerogen Solo vibrating mesh nebuliser was used in combination with the InspiredTM O2FLO high-flow therapy system. Representative adult and paediatric head models were connected to a breathing simulator, which replicated several different states of lung health. The aerosol delivery was quantified at the tracheal level using UV-spectrophotometry. Testing was performed at a range of supplemental gas flow rates applicable to both models. Positive end-expiratory pressure was measured pre-, during and post-nebulisation. The increases in supplemental gas flow rates resulted in a decrease in aerosol delivery, irrespective of lung health. Large tidal volumes and extended inspiratory phases were associated with the greatest aerosol delivery. Gas flow to inspiratory flow ratios of 0.29-0.5 were found to be optimum for aerosol delivery. To enhance aerosol delivery to patients receiving high-flow nasal oxygen therapy, respiratory therapists should keep supplemental gas-flow rates below the inspiratory flow of the patient.

Evaluation of a Novel Dry Powder Surfactant Aerosol Delivery System for Use in Premature Infants Supported with Bubble CPAP.

Aerosolized lung surfactant therapy during nasal continuous positive airway pressure (CPAP) support avoids intubation but is highly complex, with reported poor nebulizer efficiency and low pulmonary deposition. The study objective was to evaluate particle size, operational compatibility, and drug delivery efficiency with various nasal CPAP interfaces and gas humidity levels of a synthetic dry powder (DP) surfactant aerosol delivered by a low-flow aerosol chamber (LFAC) inhaler combined with bubble nasal CPAP (bCPAP). A particle impactor characterized DP surfactant aerosol particle size. Lung pressures and volumes were measured in a preterm infant nasal airway and lung model using LFAC flow injection into the bCPAP system with different nasal prongs. The LFAC was combined with bCPAP and a non-heated passover humidifier. DP surfactant mass deposition within the nasal airway and lung was quantified for different interfaces. Finally, surfactant aerosol therapy was investigated using select interfaces and bCPAP gas humidification by active heating. Surfactant aerosol particle size was 3.68 µm. Lung pressures and volumes were within an acceptable range for lung protection with LFAC actuation and bCPAP. Aerosol delivery of DP surfactant resulted in variable nasal airway (0-20%) and lung (0-40%) deposition. DP lung surfactant aerosols agglomerated in the prongs and nasal airways with significant reductions in lung delivery during active humidification of bCPAP gas. Our findings show high-efficiency delivery of small, synthetic DP surfactant particles without increasing the potential risk for lung injury during concurrent aerosol delivery and bCPAP with passive humidification. Specialized prongs adapted to minimize extrapulmonary aerosol losses and nasal deposition showed the greatest lung deposition. The use of heated, humidified bCPAP gases compromised drug delivery and safety. Safety and efficacy of DP aerosol delivery in preterm infants supported with bCPAP requires more research.