Breathing Circuits

Question 1

What are examples of an open circuit?

Answer 1

NO rebreathing and NO reservoir:

Insufflation
Nasal Cannula
Open drop
Simple Mask

Question 2

What are examples of a semi-open circuit?

Answer 2

NO rebreathing WITH a resevoir:

Mapleson Circuit
Circle Circuit (if FGF > Mv)

Question 3

What are examples of a semi-closed circuit?

Answer 3

PARTIAL rebreathing WITH a resevoir:

Circle system with FGF < Mv)

Question 4

What are examples of a closed circuit?

Answer 4

FULL rebreathing WITH a resevoir:

Circle system when FGF is very low and the APL is closed

Question 5

What are two common system malfunctions that increase CO2 rebreathing?

Answer 5

1. Exhausted scrubber
2. Incompetent Unidirectional Valves

Question 6

Which Mapleson circuit is best for spontaneous ventilation?

Answer 6

Mapleson A

Question 7

Which Mapleson circuit is worst for spontaneous ventilation?

Answer 7

Mapleson B

Question 8

Which Mapleson circuit is best for controlled ventilation?

Answer 8

Mapleson D

Question 9

Which Mapleson circuit is worst for controlled ventilation?

Answer 9

Mapleson A

Question 10

Unlike circle systems, Mapleson circuits do not have:

Answer 10

Unidirectional Valves
CO2 absorbers

Question 11

ALL Mapleson circuits are ________

Answer 11

semi-open (non-rebreathing) circuits

Question 12

Where is the APL valve located in Mapleson A and D circuits:

Answer 12

A: APL is by the Airway
D: APL is by the Drugs

Question 13

Where is the fresh gas inlet in Mapleson A and D circuits?

Answer 13

A: Near the bag
D: Near the patient

Question 14

Mapleson A circuits are the only circuits that:

Answer 14

have the FGF next to the bag

Question 15

The Mapleson D is the only circuit with:

Answer 15

the APL valve away from the patient

Question 16

What are the advantages of Mapleson circuits?

Answer 16

Question 17

What are the disadvantages of Mapleson circuits?

Answer 17

Question 18

What FGF is required to prevent rebreathing with a Mapleson circuit?

Answer 18

Generally 2.5x the Mv

Question 19

What is the Bain system?

Answer 19

A modified Mapleson D

Question 20

Answer 20

Mapleson A

Question 21

Answer 21

Mapleson B

Question 22

Answer 22

Mapleson C

Question 23

Answer 23

Mapleson D

Question 24

Answer 24

Mapleson E
(Ayre’s T Piece)

Question 25

Answer 25

Mapleson F (Jackson Reese)

Question 26

The Jackson Reese is also known as the:

Answer 26

Mapleson F

Question 27

The resistance to gas flow through the anesthesia circuit is:

Answer 27

Less than 1 cmH2o per liter per minute Less than half what it is for normal breathing

Question 28

what is the internal volume of the typical adult anesthesia circuit?

Answer 28

400-500ml

Question 29

What is the max amount of CO2 that can be absorbed by 100g of absorbent?

Answer 29

26L for every 100g of absorbent

Question 30

By weight, what is the primary component of soda lime?

Answer 30

Calcium hydroxide