DM1 Pt4-5 Anaesthesia breathing systems Flashcards
What are the key features of an ideal breathing system for maintaining anesthesia in cats?
The system should have low dead space and low resistance to respiration.
What are examples of breathing systems suitable for use in cats?
Ayres T Piece with Jackson Rees modification, mini Lack, and Humphrey ADE circuit.
What is the function of the Jackson Rees modification in the Ayres T Piece?
The Jackson Rees modification adds a reservoir bag to the T Piece, allowing manual support of respiration using Intermittent Positive Pressure Ventilation (IPPV).
How is the fresh gas flow (FGF) rate calculated for cats using an Ayres T Piece?
FGF (liters/min) = 2-3 x Minute Volume, where Minute Volume ≈ 250 ml/kg.
What is the minute volume of a 5 kg cat?
Minute Volume = 5 kg x 250 ml/kg = 1.25 liters.
What fresh gas flow rate is needed for a 5 kg cat using the Ayres T Piece?
FGF = 3 x 1.25 liters = 3.75 liters/minute.
What minimum oxygen concentration should be used in the carrier gas mixture?
The oxygen concentration in the gas mixture should be at least 30%.
What is the Humphrey ADE circuit, and why is it useful?
The Humphrey ADE circuit combines the advantages of a Lack breathing system (A) with those of a T Piece (E) in one system, offering flexibility in anesthesia maintenance.
Why is it important to understand the function of the breathing circuit used in anesthesia?
Understanding how the circuit functions ensures safe use in clinical patients, especially since the circuits can be expensive and improper use can lead to complications.
