Click on the BEST configuration for spontaneous ventilation.
Study on!!!!
There are — different configurations of the Mapleson circuit
6
(A-F)
All Mapleson Circuits are classified as —– or non-rebreathing circuits
“semi-open”
All Mapleson Circuits are classified as semi-open or non-rebreathing circuits. Since inhaled and exhaled gases travel through the same tubing, there is a risk of
rebreathing
Mapleson Circuits - How Do They Work?
During expiration, gas containing —– enters the corrugated tubing and travels away from the patient
Carbon dioxide
After expiration but before the next inspiration, the —– continues to washout exhaled gas left inside the corrugated tubing.
FGF
During inhalation, the patient breathes in fresh gas. If the FGF is —–, the patient will also breathe in exhaled gas leftover in the corrugated tubing.
“inadequate”
Rebreathing is —– with a higher FGF, a smaller tidal volume, and a longer expiratory time
“minimized”
—– monitoring is the best method of determining the amount of fresh gas flow required to prevent rebreathing (look at the baseline of the capnograph).
End-tidal CO2
Mapleson Circuits have a Reservoir bag
True
Mapleson Circuits have a Fresh gas inlet
True
Mapleson Circuits have a Corrugated circuit tubing
True
Mapleson Circuits have an APL valve
True
(Except Maplesson E)
A Mapleson Circuit a Mask
True
Mapleson –=- does not contain an APL valve or reservoir bag
Mapleson E
Mapleson Circuits do Not have Unidirectional valves
True
Mapleson Circuits do Not have CO2 absorber
True
Which is the Best Mapleson Circuit?
Well, that depends if the circuit will be used for —– or —– ventilation. You should know which are the best and worst for each mode of ventilation.
Spontaneous or Controlled
Mapleson — is the best for Spontaneous Ventilation
Mapleson A
(A > DFE > CB)
Mapleson — is the worst for Spontaneous Ventilation
“Mapleson B”
Mapleson — is the best for Controlled Ventilation
Mapleson D
(DFE >BC> A)
Mapleson — is the worst for Controlled Ventilation
“Mapleson A”
If you really want to get picky, the amount of rebreathing is a function of many things. These include:
Fresh gas flow
Minute ventilation
Mode of ventilation
Respiratory rate
Tidal volume
Inspiratory flow rate
l: E ratio
Volume of the reservoir bag
Volume of corrugated tubing
Use of a mask, LMA, or endotracheal tube.
Fresh gas flow affects the amount of rebreathing
True
True
Minute ventilation affects the amount of rebreathing
True
Mode of ventilation affects the amount of rebreathing
True
Respiratory rate affects the amount of rebreathing
True
Tidal volume affects the amount of rebreathing
True
Inspiratory flow rate affects the amount of rebreathing
True
l: E ratio affects the amount of rebreathing
True
The volume of the reservoir bag affects the amount of rebreathing
True
The volume of corrugated tubing affects the amount of rebreathing
True
The use of a mask, LMA, or endotracheal tube affects the amount of rebreathing
True
It’s impossible to predict exactly how much FGF is required to prevent rebreathing. As a general rule ~ — times the patient’s minute ventilation should be enough in most cases
~ 2.5 times
It’s impossible to predict exactly how much FGF is required to prevent rebreathing. As a general rule ~ 2.5 times the patient’s minute ventilation should be enough in most cases. There are exceptions, however. A Mapleson A requires a FGF of ~ — L/min during controlled ventilation!
~ 20 L/min
When to Use a Mapleson Circuit? By knowing the —– and —– of the Mapleson designs, you can easily determine when to use them.
“advantages and disadvantages”
Mapleson Circuits have —– airway resistance (good for peds)
“Less”
Mapleson Circuits are Convenient
True
Mapleson Circuits are —– scavenged
“Easily”
Which Mapleson Circuit prevents heat loss
Bain circuit
Mapleson Circuits —– apparatus dead space
“increase”
Mapleson Circuits require —– FGF to prevent rebreathing
high FGF
Mapleson Circuits are associated with Loss of heat and humidity
True
(Bain circuit prevents heat loss)
Mapleson Circuits are an —– use of inhaled anesthetics
“inefficient”
Mapleson Circuits are associated with the Risk of environmental pollution
True
Unrecognized kinking of fresh gas hose is possible in —– circuit
Bain circuit
Unrecognized kinking of fresh gas hose is possible in Bain circuit. Use —– test
Pethick test
Click on the BEST configuration for spontaneous ventilation.
Mapleson A
The first circuit is the Mapleson —.
Mapleson E
The second circuit is the Mapleson —. This is the best configuration for controlled ventilation
Mapleson D
The third circuit is the Mapleson — or —–.
Mapleson F or Jackson-Rees
The fourth circuit in the image is the Mapleson —–. This is the best configuration for spontaneous ventilation
Mapleson A
References:
Barash. Clinical Anesthesia. 8th ed. 20 17 . p. 679-680. Nagelhout. Nurse Anesthesia. 6th ed. 2018. p. 249-250.
