Flow Recirculation in Cartilaginous Ring Cavities of Human Trachea Model

Evans, Humberto Bocanegra; Castillo, Luciano

doi:10.1089/jamp.2017.1435

Cited by 3 publications

(10 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…(21) High drug deposition was expected in the trachea owing to the presence of the cartilaginous rings. The presence of the cartilaginous rings in the trachea was shown to greatly influence air flow and particle deposition, (19,(23)(24)(25)(26)(27) owing to inertial impaction (dominating the particle dynamics) (25,26) and enhanced turbulence levels. (26) Russo et al (25) conducted a numerical study investigating the effect of the cartilaginous rings by comparing airflow and particle deposition in a trachea model with and without rings.…”

Section: Discussionmentioning

confidence: 99%

“…However, the authors found that the effect of the rings did not propagate to bifurcation downstream. Montoya Segnini et al (19) investigated this phenomenon in vitro, using Particle Image Velocimetry and Particle Tracking Velocimetry. The effect of the trachea rings on the airflow and particle recirculation, particularly near the walls, was determined.…”

Section: Discussionmentioning

confidence: 99%

“…(18) The average dimensions of male subjects were used with a trachea length of 104 mm and anteroposterior diameter of 23 mm and a transverse diameter of 19 mm, as given in Figure 3. The trachea model used in this study included 14 rings within 104 mm following ring spacing and thickness reported in the study of Montoya Segnini et al (19)…”

Section: Design Of Trachea Prototypementioning

confidence: 99%

See 2 more Smart Citations

In Vitro Measurements of Spiriva Respimat Dose Delivery in Mechanically Ventilated Tracheostomy Patients

Mehri

Alatrash

Ogrodnik

et al. 2020

Journal of Aerosol Medicine and Pulmonary Drug Delivery

View full text Add to dashboard Cite

Background: For patients with severe chronic obstructive pulmonary disease under invasive mechanical ventilation, medication for aerosol therapy is delivered through tracheostomy or endotracheal airways. Typically, these medications (such as bronchodilators) are long-acting formulations that are delivered through Soft Mist Ô Inhalers (SMI), or Pressurized Metered-Dose Inhalers. The Respimat Ò SMI has been shown to have increased efficiency because of its slow and prolonged aerosol mist and has gained popularity in clinical settings. However, the Respimat was not designed for drug delivery through artificial airways. Therefore, there is a need for SMI adapters in intensive care for use in mechanical ventilator circuits. The purpose of this study was to evaluate the performance of a new Respimat adapter (ODAPT Ô for mechanical ventilator [ODAPT MV]) for use in mechanical ventilator circuits which, in combination with a Pulmodyne T-piece adapter, allows use without interruption of the circuit in case of medication replacement. Methods: Tiotropium delivery to the lungs, using Respimat, was assessed using the ODAPT MV adapter within an in vitro setup, including a three-dimensional printed trachea model and a mechanical ventilator. Medication deposition and losses were investigated using two commonly used tracheostomy tube (TT) sizes (6 and 8 mm inner canula) for two flow rates (45 and 60 L/min) under different conditions (30%-50%. and 100% relative humidity [RH]). Medication delivery using the ODAPT MV adapter was compared with the RTC-26C in-line adapter under similar conditions (8 mm TT size, 100% RH at 45 L/min). Results: It was found that 7.1%-13.4% of the nominal dose (ND) was lost in the ODAPT MV adapter for different TT size, RH, and flow rates used. Higher losses were found in the inhaler's mouthpiece ranging from 15.7% to 29.1% ND. The percentage of the delivered medication reaching the lungs was determined to be 13.7%-18.5% ND delivered without significant differences between the experimental conditions tested. The ODAPT MV performed well compared with the RTC-26C under similar conditions (17.9% and 16.6% ND, respectively). Conclusion:The medication delivered through mechanical ventilation using the ODAPT MV adapter represents about one third the dose delivered directly through the Respimat SMI in vivo.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

Section: Design Of Trachea Prototypementioning

confidence: 99%

See 1 more Smart Citation

In Vitro Measurements of Spiriva Respimat Dose Delivery in Mechanically Ventilated Tracheostomy Patients

Mehri

Alatrash

Ogrodnik

et al. 2020

Journal of Aerosol Medicine and Pulmonary Drug Delivery

View full text Add to dashboard Cite

show abstract

“…Even though the trachea and main bronchi have undulated walls as a result of the cartilaginous rings [ 26 , 33 ], most research in respiratory fluid dynamics omits these features under the assumption that their effect is negligible. Nevertheless, existing research points to the importance of these small protrusions in both flow structure and aerosol deposition [ 6 , 27 , 33 ]. It is well established that surface roughness can have significant impact on wall-bounded flows [ 16 ], particularly when an adverse pressure gradient (APG), for example, an expansion in the cross-sectional area, is present [ 30 ].…”

Section: Introductionmentioning

confidence: 99%

“…The few studies that have evaluated the effects introduced by cartilaginous rings have found increased particle deposition [ 33 , 44 ], increased shear over the ring surface [ 14 , 39 ], reduced flow separation in the bifurcation [ 6 ], flow recirculation in the ring cavity [ 27 ], and flow asymmetry into the lungs [ 14 ].…”

Section: Introductionmentioning

confidence: 99%

Effect of cartilaginous rings in tracheal flow with stenosis

et al. 2023

Self Cite

View full text Add to dashboard Cite

Background In respiratory fluid dynamics research, it is typically assumed that the wall of the trachea is smooth. However, the trachea is structurally supported by a series of cartilaginous rings that create undulations on the wall surface, which introduce perturbations into the flow. Even though many studies use realistic Computer Tomography (CT) scan data to capture the complex geometry of the respiratory system, its limited spatial resolution does not resolve small features, including those introduced by the cartilaginous rings. Results Here we present an experimental comparison of two simplified trachea models with Grade II stenosis (70% blockage), one with smooth walls and second with cartilaginous rings. The use a unique refractive index-matching method provides unprecedented optical access and allowed us to perform non-intrusive velocity field measurements close to the wall (e.g., Particle Image Velocimetry (PIV)). Measurements were performed in a flow regime comparable to a resting breathing state (Reynolds number ReD = 3350). The cartilaginous rings induce velocity fluctuations in the downstream flow, enhancing the near-wall transport of momentum flux and thus reducing flow separation in the downstream flow. The maximum upstream velocity in the recirculation region is reduced by 38%, resulting in a much weaker recirculation zone— a direct consequence of the cartilaginous rings. Conclusions These results highlight the importance of the cartilaginous rings in respiratory flow studies and the mechanism to reduce flow separation in trachea stenosis.

show abstract

Place of nebulizer therapy in the treatment of bronchial asthma in children

Potapova

2022

Medicinskij sovet

View full text Add to dashboard Cite

The review article presents an analysis of the data of foreign and domestic researchers characterizing the effectiveness of nebulizer therapy for bronchial asthma in children. The paper considers new data comparing the effectiveness of aerosol delivery devices. The advantage of inhalation therapy, which determines its widespread use in childhood, is its rapid delivery to the respiratory tract, high local and low systemic concentrations of the drug in target organs. Difficulties in observing the correct inhalation technique due to the difficulty of synchronizing inhalation and drug delivery, especially in young children, remain an urgent problem in the practice of treating chronic bronchopulmonary diseases, which leads to a severe and uncontrolled course, disability and adverse outcomes. The main disadvantage of ultrasonic nebulizers is the inactivation of suspensions, antibiotics and other drugs. Widely used jet nebulizers create noise during inhalation, have a large residual volume in the nebulizer chamber. In this regard, the improvement of delivery forms continues, taking into account the anatomical and physiological characteristics of the respiratory organs, the age of patients and comorbid conditions. The characteristics of the optimal inhaler include simplicity and ease of use, reliability, the possibility of effective inhalation of various drugs in combination with economical consumption. From this point of view, one of the universal means of transporting aerosols is membrane or electronic mesh (mesh) nebulizers, which provide excellent regional drug deposition in all age groups of children. The rapid achievement of clinical effect, compactness, mobility expand the possibilities of using mesh nebulizers at all levels of medical care.

show abstract

Flow Recirculation in Cartilaginous Ring Cavities of Human Trachea Model

Cited by 3 publications

References 29 publications

In Vitro Measurements of Spiriva Respimat Dose Delivery in Mechanically Ventilated Tracheostomy Patients

In Vitro Measurements of Spiriva Respimat Dose Delivery in Mechanically Ventilated Tracheostomy Patients

Effect of cartilaginous rings in tracheal flow with stenosis

Place of nebulizer therapy in the treatment of bronchial asthma in children

Contact Info

Product

Resources

About