Breathing Circuits-APEX

For spontaneous ventilation, which circuit is best and which circuit is worst?

All Dogs Bite, A>DFE>CB;

Best: Mapelson A

Worst: Mapelson B

For controlled ventilation, which circuit is best and worst?

“Don’t Be Arrogant”

Best: Mapelson D

Worst: Mapelson A

Which Mapelson circuit is most likely to cause Hypercarbia when receiving controlled ventilation w/ FGF of 5 L/min?

Mapelson A-FGF of at least 20 L/min is required

Which circuit contains a reservoir bag but does not allow rebreathing of exhaled gases?

semi-open circuits (Nonrebreathing circuits)

What components are absent in a Mapelson D?

Unidirectional Valves

CO2 absorbent

A circle system with a fresh gas flow of 3L/min is an example of a/an

Semi-closed

Which Mapelson circuits are MOST likely to be encountered in modern anesthetic practice?

D, E, F (T-piece group)

What are the 4 steps of the Pethick test when performing a pre-anesthetic check on Bain circuit?

1. Occlude the elbow at the patient end of the circuit

2. Close the APL valve

3. Use the oxygen flush valve to fill the circuit

4. Remove the occlusion at the elbow while flushing the circuit

Which circuit does not contain dead space?

Open b/c it's open to atmosphere

Between the simple face mask, T-piece, nasal cannula, and Bain system, all allow fresh gas to escape into the atmosphere except which one?

Bain System-b/c it's semi-open