1. Non-Rebreathing System
Used for patients weighing: <15 pounds
Some clinics may use a rebreather for patients as small as 6 pounds
Less than 6 pounds: non-rebreather is a MUST
There are many types: we will be discussing the Jackson-Rees (in detail) and the Bain coaxial

2. Non-Rebreathing System
Attach a clear, long, plastic hose to the fresh
gas outlet (this tube comes from the vaporizer outlet port)
Flow of gas differs from rebreathing circuit now!!
Fresh gas goes directly to the patient
Not through the unidirectional valves!
The same gas exchange happens
in the patient…

3. Non-Rebreathing System
Exhaled gas comes directly out through a separate hose.
This plastic hose is corrugated, short and much wider.
Gas now flows through the pop-off and then either into a reservoir bag OR scavenging hose.
WAG are scavenged the same
way as a rebreather

4. What’s Missing Here??
What parts on the rebreathing system are missing from the non-rebreathing system? 1. 2. 3.
How do we compensate for this?
CO2 canister, flutter valves, pressure manometer; high O2 flow rates and extra careful when PPV

5. Non-Rebreathing System
Benefits:
1. Less parts = less ________________
Smaller animals need this feature!
2. Quicker changes in Ax depth
Disadvantages:
1. Higher amount of oxygen used due to patient not-rebreathing any gas
2. Patient is only breathing cold, dry fresh gas
What can we do about this?
Resistance
Warm the inspiratory tube

6. Non-Rebreathing Systems
Jackson-Rees
Norman Mask Elbow

7. Non-rebreathing Systems
Bain coaxial
Tube within a tube- helps with warming

8. Universal Bain Block
Has a pressure manometer!

9. Oxygen Flow Rate Non-rebreathing system:
High b/c removal of CO2 is dependent on flow in the system
Can go up to 600 ml/kg/min!
Note: An inadequate fresh gas supply will result in your patient re-breathing gases…remember, there is no CO2 absorber!
300 ml/kg/min

10. Non-rebreathing Oxygen Flow Rate
Practice problem: Patient weighs 4.65 kg
How many ml/min of oxygen does the patient need?
Flow rates need to be in L/min:

11. Leak Testing (Both Breathing Circuits)
Performed before every anesthesia to check the system for leaks
The last thing you do on your anesthetic machine
*Hint: this will also tell you if your machine is hooked up correctly
Top three most common leaky parts: 1. 2. 3.
Fresh gas inlet not connected, CO2 canister misaligned, reservoir bag damaged

12. Leak Testing – Low Pressure Test
Steps: close pop-off valve AND cover end of breathing tube with something
Turn on flow meter to 2 L/min and let oxygen fill reservoir bag
Once full, turn down the O2 to 0.2 L/min
Gently squeeze the bag and listen/feel for leaks
If none, maintain a full bag for: __________ at _______________.
If the bag doesn’t hold pressure (remain full), you have a leak!
30 psi for 30 seconds

13. Things to Consider
Which breathing system may help keep a patient from becoming hypothermic?
Which rebreathing circuit provides the least resistance to the patient?
Which breathing system is more costly to use?
Which breathing system allows for the quickest change in anesthetic depth?
Any coaxial
Circle with y piece
Non-rebreather