Breathing Systems Flashcards
Describe a Magill Circuit
Non rebreathing
- Valve near patient
- Bag at machiene end
- Alveolar gas vented, dead space gas rebreathed
- Requires expiratory pause to function correctly (time for fresh gas to fill tube)
Give the flow rate for a Magill or Lack circuits
0.7-1 x MV
What circuits can be used for Medium sized dogs breathing spontaneously?
Magill, Lack and Bain
Describe a lack circuit
Modified mapelson A
- Non Rebreathing
- Inefficient for IPPV
- Parrallel (bag and valve at same end but different tubes
- For dogs over 10kg
Describe a mini lack circuit
- Non rebreathing
- Smooth inner bore tubing and lightweight valve = minimal resistance
- 1/3 flow rates of a T piece
for patients 2-10kg
What circuits can be used for patients from 2-10kg
Mini lack and T piece
Describe a bain circuit
- Non rebreathing
- Inner tube provides fresh gas directly to the patient
- High flow rates
- Excellent for IPPV (squeezing bag returns gas from expiratory limb into the patient)
What is the circuit factor for the Bain
2.5
Describe the T piece breathing circuit
- Non rebreathing
- No valve
- Low resistance
- Good for IPPV
What is the normal minute volume for an animal
250ml/0.25L per kg
How do you work out flow rates for an animal?
Circuit factor x Weight x 0.25 = L O2 required
Describe how you would work out minute volume
= Tidal volume vs resp rate (normally 0.25L per Kg in an animal)
Describe a to and fro circuit
- Rebreathing
- outdated
- dust inhailation etc
Describe a circle breathing circuit
- Efficient
- Warm and humidify air
- less pollutant
- Easy IPPV
- Use Y tubing
- One way valve system
What chemicals are usually used as absorbants in rebreathing systems
- Calcium Hydroxide(soda lime)
- Incorporates indicator to usage (check before use)
- Active soda lime generates heat (detectable by touching the cannister)
