Strategies to Reduce Surface Area Requirements for Carbon Dioxide Removal for an Intravenacaval Gas Exchange Device

The human lung comprises 24 generations of dichotomously branching tubes known as bronchi [1]. Functionally, these generations can be categorized as: (1) conducting airways which are non-alveolated and comprise the first 16 generations, and (2) the acini which consist of flexible, alveolated airways and are responsible for gas exchange. The alveoli are the most important units of the human respiratory system and provide large surface area (about 70–80 m2) for efficient gas exchange; oxygen diffuses into the blood through the alveolar epithelium, whereas carbon dioxide diffuses in the opposite direction from the blood to the lung.

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Effect of Geometric and Dynamic Parameters on Fluid Flow and Particle Dispersion in Human Lung Acini

ASME 2009 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2009-204757 ◽

2009 ◽

Author(s):

Sudhaker Chhabra ◽

Ajay K. Prasad

Keyword(s):

Carbon Dioxide ◽

Fluid Flow ◽

Gas Exchange ◽

Surface Area ◽

Respiratory System ◽

Human Lung ◽

Alveolar Epithelium ◽

Particle Dispersion ◽

Dynamic Parameters ◽

Conducting Airways

Breathing, defined as the exchange of gases between the respiratory system and the environment, is an essential process for life. The human respiratory system can be divided into three parts: (i) nose, mouth, and nasopharynx, (ii) trachea, and (iii) lungs. The human lung can be further subdivided into conducting airways which are non-alveolated and comprise the upper part of lung, and the acini which consist of flexible, alveolated airways and are responsible for gas exchange [1]. The alveoli collectively provide a large surface area (∼70 m2) for efficient gas exchange [1]; oxygen diffuses into the blood through the alveolar epithelium, whereas carbon dioxide diffuses in the opposite direction from the blood to the lung.

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Pre-clinical Evaluation of an Adult Extracoproreal Carbon Dioxide Removal System for Pediatric Application

Central Asian Journal of Global Health ◽

10.5195/cajgh.2014.167 ◽

2014 ◽

Vol 3 ◽

Author(s):

Yerbol Mussin ◽

Richard Jeffries ◽

Denis Bulanin ◽

Zhaksybay Zhumadilov ◽

Farkhad Olzhayev ◽

...

Keyword(s):

Carbon Dioxide ◽

Blood Flow ◽

Gas Exchange ◽

Pediatric Population ◽

Blood Flow Rate ◽

Carbon Dioxide Removal ◽

Respiratory Support ◽

In Vivo Studies ◽

Co2 Removal

Introduction. Adult extracorporeal carbon dioxide removal (ECCO2R) systems and pediatric ECMO share the common objectives of having a low blood flow rate and low priming volume while safely maintaining sufficient respiratory support. The Hemolung is a highly simplified adult ECCO2R system intended for partial respiratory support in adult patients with acute hypercapnic respiratory failure. The objective of this work was to conduct pre-clinical feasibility studies to determine if a highly efficient, active-mixing, adult ECCO2R system can safely be translated to the pediatric population. Methods. 14 healthy nonsedated juvenile sheep were used for acute (2 animals) and 7-day chronic (12 animals) in-vivo studies to evaluate treatment safety independently of respiratory related injuries. In all evaluations, we hypothesized that gas exchange capabilities of the Hemolung RAS in this model would be equivalent to the adult configuration performance at similar blood flows - minimum CO2 removal of 50 mL/min at a venous partial pressure of CO2 equal to 45 mmHg. Target blood flow rates were set to a minimum of 280 mL/min. Swan Ganz catheters were used under general anesthesia in the two acute subjects to evaluate blood gas status in the pulmonary artery.Results. The Hemolung RAS was found to have adequate gas exchange and pumping capabilities for full respiratory support for subjects weighing 3 – 25 kg. The Hemolung device was estimated to provide a partial respiratory support for subjects weighing 27 – 34 kg. The seven-day studies in juvenile sheep demonstrated that veno-venous extracorporeal support could be provided safely at low flows with no significant adverse reactions related to device operation.Conclusion. The study outcomes suggest the potential use of the Hemolung RAS in a veno-venous pediatric configuration to safely provide respiratory support utilizing a significantly less complex system than traditional pediatric ECMO.

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Faculty Opinions recommendation of Tidal volume lower than 6 ml/kg enhances lung protection: role of extracorporeal carbon dioxide removal.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.1168498.630691 ◽

2009 ◽

Author(s):

Nigel Webster

Keyword(s):

Carbon Dioxide ◽

Tidal Volume ◽

Carbon Dioxide Removal ◽

Extracorporeal Carbon Dioxide Removal ◽

Lung Protection

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Ratcheting Ambition to Limit Warming to 1.55C Trade-Offs between Emission Reductions and Carbon Dioxide Removal

SSRN Electronic Journal ◽

10.2139/ssrn.3063337 ◽

2017 ◽

Author(s):

Christian Holz ◽

Lori S Siegel ◽

Eleanor Johnston ◽

Andrew P Jones ◽

John Sterman

Keyword(s):

Carbon Dioxide ◽

Carbon Dioxide Removal ◽

Emission Reductions ◽

Trade Offs

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Developing Eco-Friendly and Cost-Effective Porous Adsorbent for Carbon Dioxide Capture

Molecules ◽

10.3390/molecules26071962 ◽

2021 ◽

Vol 26 (7) ◽

pp. 1962

Author(s):

Mahboubeh Nabavinia ◽

Baishali Kanjilal ◽

Noahiro Fujinuma ◽

Amos Mugweru ◽

Iman Noshadi

Keyword(s):

Carbon Dioxide ◽

Surface Area ◽

Co2 Capture ◽

High Surface ◽

Scale Up ◽

Polymer Networks ◽

High Surface Area ◽

Excellent Thermal Stability ◽

Doped Polymers ◽

Metal Doped

To address the issue of global warming and climate change issues, recent research efforts have highlighted opportunities for capturing and electrochemically converting carbon dioxide (CO2). Despite metal doped polymers receiving widespread attention in this respect, the structures hitherto reported lack in ease of synthesis with scale up feasibility. In this study, a series of mesoporous metal-doped polymers (MRFs) with tunable metal functionality and hierarchical porosity were successfully synthesized using a one-step copolymerization of resorcinol and formaldehyde with Polyethyleneimine (PEI) under solvothermal conditions. The effect of PEI and metal doping concentrations were observed on physical properties and adsorption results. The results confirmed the role of PEI on the mesoporosity of the polymer networks and high surface area in addition to enhanced CO2 capture capacity. The resulting Cobalt doped material shows excellent thermal stability and promising CO2 capture performance, with equilibrium adsorption of 2.3 mmol CO2/g at 0 °C and 1 bar for at a surface area 675.62 m2/g. This mesoporous polymer, with its ease of synthesis is a promising candidate for promising for CO2 capture and possible subsequent electrochemical conversion.

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