30 Questions
Which type of oxygenator is more prone to thrombosis and microemboli?
Direct contact oxygenators
Which type of flow allows for increased transfer of X across the barrier throughout the entire length of the system?
Countercurrent flow
What is the purpose of the sweep gas in an oxygenator?
To remove CO2 from the blood
What is the concentration of X at equilibrium in a concurrent flow system?
50%:50%
What is the relationship between bubble diameter and available surface area for gas exchange in the blood?
Inversely proportional
What is the equivalent physiological function of the sweep gas in an oxygenator?
Minute ventilation of native lung function
What are the advantages of using a membrane oxygenator over bubble oxygenators?
Reduced damage and thrombosis
What is the purpose of monitoring the function of the oxygenator during a surgical procedure?
To detect rising pressure indicating a clot
Which material is commonly used to make microporous hollow fiber oxygenators?
Polypropylene
What is the purpose of increasing the length of the blood path in microporous membrane oxygenators?
To create more effective surface area for gas exchange
What is the main difference between the movement of oxygen and carbon dioxide across the oxygenator?
Oxygen is transported on amine groups of plasma proteins, while carbon dioxide is quickly converted to bicarbonate
What is the purpose of the predetermined 'rated flow' in modern oxygenators?
To determine the maximum flow rate that will still allow appropriate oxygenation
According to Fick's First Law of Diffusion, the movement of O2 and CO2 across a barrier will be in the direction of higher to lower concentration (partial pressure) with a magnitude that is proportional to the gradient, and proportional to the area involved, and inversely proportional to the diffusion coefficient or 'diffusivity.'
The movement of O2 and CO2 across a barrier is in the direction of higher to lower concentration.
According to the text, what factors contribute to efficient gas diffusion in an oxygenator?
Low pressure drop and high surface area
If the concentration of CO2 is higher in the blood stream than in the ambient air, what will the sweep gas flow across the oxygenator do?
It will efficiently remove CO2 from the blood stream to the ambient air.
Which equation represents Fick's First Law of Diffusion?
J = -D(Do/dx)
What is the relationship between the diffusion coefficient and the diffusivity?
The diffusion coefficient is proportional to the diffusivity
What factors contribute to efficient gas diffusion in an oxygenator?
Low pressure drop across the membrane
What is the purpose of the sweep gas in an oxygenator?
To maximize gas exchange
What is the equivalent physiological function of the sweep gas in an oxygenator?
Minute ventilation of native lung function
What is the purpose of increasing the gradient across the membrane in an oxygenator?
To increase gas exchange
What is the purpose of monitoring the function of the oxygenator during a surgical procedure?
To detect clot or malfunction
What is the purpose of microporous membrane oxygenators in the operating room?
To provide short-term use with small devices
What is the main advantage of using microporous hollow fiber oxygenators over silicone membrane oxygenators?
They have lower resistance and require lower priming volumes
What happens to the pores in the fibers of microporous membrane oxygenators when exposed to blood?
They become coated with plasma proteins
What is the purpose of increasing the length of the blood path in microporous membrane oxygenators?
To create more effective surface area for gas exchange
What is the purpose of countercurrent flow in a system with two parallel tubes filled with fluid or gas separated by a permeable membrane?
To increase the efficiency of molecule exchange across the barrier
What is the purpose of the priming volume in an oxygenator?
To fill the blood phase of the device and the integrated heat exchanger
What is the definition of the oxygen reference blood flow in an oxygenator?
The flow rate of whole blood at normothermia that will increase the oxygen content of venous blood by 45 mL/L of flow
What is the advantage of using a membrane oxygenator over bubble oxygenators?
Reduced damage and thrombosis, and reduction of gaseous emboli
Test your knowledge on microporous hollow fiber oxygenators and their advantages in the operating room. Learn about their design, materials used, and benefits compared to silicone membrane oxygenators.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
