Influence of bronchial diameter change on the airflow dynamics based on a pressure-controlled ventilation system

Task of controlled ventilation in modern residential buildings is to ensure optimum quality of interior environment and fulfill hygienic and thermal technical requirements guaranteeing comfort of user. The paper discusses development and experimental verification of atypical vertical ventilation units of under pressure controlled ventilation system for residential high-rise building. Recommended concept of solution to façade detail in relation to ventilation system. Conceptual designs of alternatives of air inlet openings of under pressure controlled ventilation system for apartments of atypical vertical geometry. Optimized alternative of air inlet openings in the bottom level of vertical pilaster with function of air distribution channel for ventilation system. Laboratory experimental verification of physical properties of optimized alternative of ventilation units of under pressure controlled ventilation system in their development cycle. Hydrodynamic regime of air inlet openings of controlled ventilation system – laboratory experimental research in large rain chamber. Aerodynamic regime of natural controlled ventilation system – laboratory experimental research in large pressure chamber. Acoustic properties of natural controlled ventilation system – laboratory experimental research in acoustic chambers. Comparison by the experiment of verified parameters of ventilation units of under pressure controlled ventilation with design parameters.

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A low-cost multi-patient pressure-controlled ventilation system with individualized parameter settings

10.1101/2020.04.17.20069799 ◽

2020 ◽

Author(s):

Alcendino Cândido Jardim-Neto ◽

Carrie E. Perlman

Keyword(s):

Low Cost ◽

Ventilation System ◽

Pressure Control ◽

Mechanical Ventilators ◽

Health Crisis ◽

Major Health ◽

Controlled Ventilation ◽

Pressure Controlled Ventilation ◽

Multiple Patients ◽

Pressure Controlled

AbstractIn a major health crisis, demand for mechanical ventilators may exceed supply. This scenario has led to the idea of connecting ventilation circuits in parallel to ventilate multiple patients simultaneously with the same machine. However, simple parallel connection may be harmful when the patients’ respiratory system mechanics differ. The aim of this work was to develop and test a low-cost, multi-patient, pressure-controlled ventilation system in which parameter settings could be individualized. Two types of circuits were built from polyvinyl chloride plumbing tubes and connectors, with ball valves and water columns used to control pressures. The circuits were connected to test lungs of differing compliances, ventilated in parallel at 20 cycles per minute and assessed for control error, variability and interdependency during peak inspiratory (20 to 35 cmH2O, in 5 cmH2O steps) and positive end-expiratory (5 to 20 to 5 cmH2O, in 5 cmH2O steps) pressure changes in one of the circuits. Results showed control errors lower than 1 cmH2O, a maximum standard deviation in pressure of 1.4 cmH2O and no dependency between the parallel circuits during the pressure maneuvers or a controlled disconnection/reconnection. This pressure-control system might be used to expand a commercial ventilator or, with constant gas inflow and an automated outlet valve, as a stand-alone ventilator with individually-controlled settings for multiple patients. In conclusion, the proposed solution is presented as a potentially reliable strategy for safely individualizing pressure-control parameters in a multi-patient ventilation system during a major health crisis.

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New Façade Ventilation Units of under Pressure Controlled Ventilation System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1057.113 ◽

2014 ◽

Vol 1057 ◽

pp. 113-120

Author(s):

Boris Bielek ◽

Daniel Szabó

Keyword(s):

Experimental Research ◽

Experimental Verification ◽

Ventilation System ◽

Acoustic Properties ◽

High Rise ◽

Controlled Ventilation ◽

High Rise Building ◽

Air Inlet ◽

Pressure Controlled Ventilation ◽

Pressure Controlled

Task of controlled ventilation in modern residential buildings is to ensure optimum quality of interior environment and fulfill hygienic and thermal technical requirements guaranteeing comfort of user. The paper discusses development and experimental verification of atypical vertical ventilation units of under pressure controlled ventilation system for residential high-rise building. Recommended concept of solution to façade detail in relation to ventilation system. Optimized alternative of air inlet openings in the bottom level of vertical pilaster with function of air distribution channel for under pressure controlled ventilation system. The paper discusses laboratory experimental verification of physical properties of optimized alternative of ventilation units of under pressure controlled ventilation system for high-rise residential building in their development cycle. Boundary conditions of physical designing of envelope structures for load of wind-driven rain and their modifications for high-rise building in the locality of Bratislava. Hydrodynamic regime of air inlet openings of controlled ventilation system – maintaining water impermeability of air inlet openings of the ventilation system under the effect of wind-driven rain – laboratory experimental research in large rain chamber, its results and necessary construction modifications of elements of ventilation units. Aerodynamic regime of natural controlled ventilation system – quantification of volume of air flow rate through ventilation units in dependence to air pressure difference - laboratory experimental research in large pressure chamber. Acoustic properties of natural controlled ventilation system – quantification of index of air impermeability of controlled ventilation system in open and closed position - laboratory experimental research in acoustic chambers. Comparison by the experiment of verified parameters of ventilation units of under pressure controlled ventilation with design parameters.

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Transparent Elemental Facade with an Integrated Ventilation Unit for a High-Rise Building – Development and Experimental Verification

Slovak Journal of Civil Engineering ◽

10.2478/sjce-2018-0030 ◽

2018 ◽

Vol 26 (4) ◽

pp. 66-77 ◽

Cited By ~ 1

Author(s):

Boris Bielek ◽

Daniel Szabó ◽

Milan Lavrinčík

Keyword(s):

Experimental Research ◽

Experimental Verification ◽

Ventilation System ◽

Acoustic Properties ◽

High Rise ◽

Controlled Ventilation ◽

High Rise Building ◽

Air Inlet ◽

Pressure Controlled Ventilation ◽

Pressure Controlled

Abstract The article documents the development of a modular transparent elemental facade. The cooperative development was realized in two areas, i.e., the development of facade ventilation units for an under-pressure ventilation system and experimental verification in a laboratory of a facade panel and optimization of its acoustic parameters. The task of controlled ventilation in modern residential buildings is to ensure the optimum quality of the interior environment and fulfill hygienic and thermal technical requirements that guarantee the comfort of the users. The paper discusses the development and experimental verification of atypical vertical ventilation units of an under-pressure controlled ventilation system for a residential high-rise building. A recommended concept for the facade´s details has been developed in relation to the ventilation system. Conceptual designs of alternatives to the air inlet openings of an under-pressure controlled ventilation system for the apartments with an atypical vertical geometry were proposed. An optimized alternative to air inlet openings in the bottom level of a vertical pilaster with the function of an air distribution channel for a ventilation system has been selected and developed. Laboratory experiments have verified the physical properties of the optimized alternative ventilation units of the under-pressure controlled ventilation system in their development cycle. The hydrodynamic regime of the air inlet openings of the controlled ventilation system has been verified by experimental research in a laboratory large rain chamber. The aerodynamic regime of a naturally controlled ventilation system was verified by experimental research in a large laboratory pressure chamber. The acoustic properties of the naturally controlled ventilation system were verified by experimental research in a laboratory´s acoustic chambers. The verified parameters of the ventilation units of the under-pressure controlled ventilation obtained by the experiment were compared with the design parameters. An experimental assessment of the mechanical, thermal and acoustical parameters of the elemental modular facade was carried out in a laboratory. At the end of the article, the results and conclusions of the laboratory experiment are summarized.

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A prospective evaluation of the new laryngeal tube suction-disposable in paralyzed, anesthetized pediatric patients under pressure-controlled ventilation

Minerva Anestesiologica ◽

10.23736/s0375-9393.20.14594-2 ◽

2020 ◽

Vol 86 (9) ◽

Author(s):

Mostafa Somri ◽

Luis A. Gaitini ◽

Anan Safadi ◽

Jalaa Hossein ◽

Nashed Ebraheem ◽

...

Keyword(s):

Pediatric Patients ◽

Laryngeal Tube ◽

Prospective Evaluation ◽

Controlled Ventilation ◽

Pressure Controlled Ventilation ◽

Tube Suction ◽

Pressure Controlled

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Comparison of Volume-Guaranteed or -Targeted, Pressure-Controlled Ventilation with Volume-Controlled Ventilation during Elective Surgery: A Systematic Review and Meta-Analysis

Journal of Clinical Medicine ◽

10.3390/jcm10061276 ◽

2021 ◽

Vol 10 (6) ◽

pp. 1276

Author(s):

Volker Schick ◽

Fabian Dusse ◽

Ronny Eckardt ◽

Steffen Kerkhoff ◽

Simone Commotio ◽

...

Keyword(s):

Systematic Review ◽

Elective Surgery ◽

Meta Analysis ◽

Lung Ventilation ◽

One Lung Ventilation ◽

Controlled Ventilation ◽

Pressure Controlled Ventilation ◽

Volume Controlled Ventilation ◽

Volume Controlled ◽

Pressure Controlled

For perioperative mechanical ventilation under general anesthesia, modern respirators aim at combining the benefits of pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV) in modes typically named “volume-guaranteed” or “volume-targeted” pressure-controlled ventilation (PCV-VG). This systematic review and meta-analysis tested the hypothesis that PCV-VG modes of ventilation could be beneficial in terms of improved airway pressures (Ppeak, Pplateau, Pmean), dynamic compliance (Cdyn), or arterial blood gases (PaO2, PaCO2) in adults undergoing elective surgery under general anesthesia. Three major medical electronic databases were searched with predefined search strategies and publications were systematically evaluated according to the Cochrane Review Methods. Continuous variables were tested for mean differences using the inverse variance method and 95% confidence intervals (CI) were calculated. Based on the assumption that intervention effects across studies were not identical, a random effects model was chosen. Assessment for heterogeneity was performed with the χ2 test and the I2 statistic. As primary endpoints, Ppeak, Pplateau, Pmean, Cdyn, PaO2, and PaCO2 were evaluated. Of the 725 publications identified, 17 finally met eligibility criteria, with a total of 929 patients recruited. Under supine two-lung ventilation, PCV-VG resulted in significantly reduced Ppeak (15 studies) and Pplateau (9 studies) as well as higher Cdyn (9 studies), compared with VCV [random effects models; Ppeak: CI −3.26 to −1.47; p < 0.001; I2 = 82%; Pplateau: −3.12 to −0.12; p = 0.03; I2 = 90%; Cdyn: CI 3.42 to 8.65; p < 0.001; I2 = 90%]. For one-lung ventilation (8 studies), PCV-VG allowed for significantly lower Ppeak and higher PaO2 compared with VCV. In Trendelenburg position (5 studies), this effect was significant for Ppeak only. This systematic review and meta-analysis demonstrates that volume-targeting, pressure-controlled ventilation modes may provide benefits with respect to the improved airway dynamics in two- and one-lung ventilation, and improved oxygenation in one-lung ventilation in adults undergoing elective surgery.

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0435. Pressure-support ventilation compared to pressure-controlled ventilation in experimental emphysema

Intensive Care Medicine Experimental ◽

10.1186/2197-425x-2-s1-p27 ◽

2014 ◽

Vol 2 (S1) ◽

Author(s):

GA Padilha ◽

I Henriques ◽

L Moraes ◽

MV Oliveira ◽

IP Ramos ◽

...

Keyword(s):

Pressure Support Ventilation ◽

Pressure Support ◽

Support Ventilation ◽

Controlled Ventilation ◽

Pressure Controlled Ventilation ◽

Experimental Emphysema ◽

Pressure Controlled

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Lung regional stress and strain as a function of posture and ventilatory mode

Journal of Applied Physiology ◽

10.1152/japplphysiol.00439.2010 ◽

2011 ◽

Vol 110 (5) ◽

pp. 1374-1383 ◽

Cited By ~ 35

Author(s):

Gaetano Perchiazzi ◽

Christian Rylander ◽

Antonio Vena ◽

Savino Derosa ◽

Debora Polieri ◽

...

Keyword(s):

Computed Tomography ◽

Volume Control ◽

Dynamic Strain ◽

Positive Pressure ◽

Stress And Strain ◽

Prone Positioning ◽

Ventilatory Mode ◽

Controlled Ventilation ◽

Pressure Controlled Ventilation ◽

Pressure Controlled

During positive-pressure ventilation parenchymal deformation can be assessed as strain (volume increase above functional residual capacity) in response to stress (transpulmonary pressure). The aim of this study was to explore the relationship between stress and strain on the regional level using computed tomography in anesthetized healthy pigs in two postures and two patterns of breathing. Airway opening and esophageal pressures were used to calculate stress; change of gas content as assessed from computed tomography was used to calculate strain. Static stress-strain curves and dynamic strain-time curves were constructed, the latter during the inspiratory phase of volume and pressure-controlled ventilation, both in supine and prone position. The lung was divided into nondependent, intermediate, dependent, and central regions: their curves were modeled by exponential regression and examined for statistically significant differences. In all the examined regions, there were strong but different exponential relations between stress and strain. During mechanical ventilation, the end-inspiratory strain was higher in the dependent than in the nondependent regions. No differences between volume- and pressure-controlled ventilation were found. However, during volume control ventilation, prone positioning decreased the end-inspiratory strain of dependent regions and increased it in nondependent regions, resulting in reduced strain gradient. Strain is inhomogeneously distributed within the healthy lung. Prone positioning attenuates differences between dependent and nondependent regions. The regional effects of ventilatory mode and body positioning should be further explored in patients with acute lung injury.

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Effect of mechanical pressure-controlled ventilation in patients with disturbed respiratory function during laparoscopic cholecystectomy

Vojnosanitetski pregled ◽

10.2298/vsp1301009s ◽

2013 ◽

Vol 70 (1) ◽

pp. 9-15

Author(s):

Maja Surbatovic ◽

Zoran Vesic ◽

Dragan Djordjevic ◽

Sonja Radakovic ◽

Snjezana Zeba ◽

...

Keyword(s):

Laparoscopic Cholecystectomy ◽

Respiratory Function ◽

Respiratory Diseases ◽

Positive Pressure ◽

Time Interval ◽

Time Intervals ◽

Controlled Ventilation ◽

Arterial Blood ◽

Pressure Controlled Ventilation ◽

Pressure Controlled

Background/Aim: Laparoscopic cholecystectomy is considered to be the gold standard for laparoscopic surgical procedures. In ASA III patients with concomitant respiratory diseases, however, creation of pneumoperitoneum and the position of patients during surgery exert additional negative effect on intraoperative respiratory function, thus making a higher challenge for the anesthesiologist than for the surgeon. The aim of this study was to compare the effect of intermittent positive pressure ventilation (IPPV) and pressure controlled ventilation (PCV) during general anesthesia on respiratory function in ASA III patients submitted to laparoscopic cholecystectomy. Methods. The study included 60 patients randomized into two groups depending on the mode of ventilation: IPPV or PCV. Respiratory volume (VT), peak inspiratory pressure (PIP), compliance (C), end-tidal CO2 pressure (PETCO2), oxygen saturation (SpO2), partial pressures of O2, CO2 (PaO2 and PaCO2) and pH of arterial blood were recorded within four time intervals. Results. There were no statistically significant differences in VT, SpO2, PaO2, PaCO2 and pH values neither within nor between the two groups. In time interval t1 there were no statistically significant differences in PIP, C, PETCO2 values between the IPPV and the PCV group. But, in the next three time intervals there was a difference in PIP, C, and PETCO2 values between the two groups which ranged from statistically significant to highly significant; PIP was lower, C and PETCO2 were higher in the PCV group. Conclusion. Pressure controlled ventilation better maintains stability regarding intraoperative ventilatory parameters in ASA III patients with concomitant respiratory diseases during laparoscopic cholecystectomy.

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