← All decks
The first 25 slides, exactly as they appear. The full deck has 83 content slides.
Anaesthesiology
Breathing systems
Built from Al-Shaikh — Essentials of Equipment in Anaesthesia, Critical Care and Peri-operative Medicine, 6e
What’s inside
11 sections · 83 slides
Overview
- What this deck will teach you
The fundamentals
What a breathing system must achieve
- The three jobs of any breathing system
- Rebreathing and efficiency - the key idea
- Properties of the ideal breathing system
The shared components
APL valve, reservoir bag and tubing
- The adjustable pressure limiting (APL) valve
- Inside the APL valve
- How the APL valve behaves in use
- APL valve - safety features and pitfalls
- A modern APL valve with fixed safety relief
- The reservoir bag
- Standard 2-litre adult reservoir bag
- What the reservoir bag does for you
- 0.5-L double-ended reservoir bag for the T-piece
- The tubing
The Mapleson classification
One family, defined by where the parts sit
- How the Mapleson family is organised
- The Mapleson classification of breathing systems
- The one rule that explains everything: mode matters
Mapleson A
The Magill and Lack systems
- Magill system - the classic Mapleson A
- How the Magill (Mapleson A) works
- Magill - limits and drawbacks
- Lack system - a tidier Mapleson A
- Lack breathing system - coaxial and parallel versions
Mapleson B and C
Simple systems for recovery and resuscitation
- Mapleson B and C
- Mapleson C system (adult)
Mapleson D
The Bain system
- Bain system - components
- The Bain (coaxial Mapleson D) breathing system
- Machine end of the coaxial Bain
- Bain - mechanism and efficiency
- Mapleson D mechanism during spontaneous ventilation
- Running the Bain with a ventilator
- Bain system connected to a ventilator
- Bain - safety and the classic exam point
T-piece systems
Mapleson E and F for children
- The T-piece (Mapleson E and F)
- Paediatric T-piece breathing system
- T-piece mechanism of action
- T-piece - how it performs
- Scavengeable T-piece with APL valve and closed bag
- T-piece - the trade-offs
The Humphrey ADE
One system, three modes
- Humphrey ADE - the versatile all-rounder
- The Humphrey block - spontaneous and ventilator modes
- Humphrey ADE - why it works so well
The circle system and soda lime
Chemically absorbing CO2 to run at very low flows
- Why the circle system changed everything
- Fresh gas flow to prevent rebreathing (mL/kg/min)
- Three ways to run the circle, by how low the flow goes
- The circle breathing system
- Circle system - the components
- How the circle works
- Circle mechanism of action
- Circle system unidirectional valve
- What soda lime is made of
- Granule size, capacity and alternatives
- The soda lime chemistry - the big picture
- Step 1 - CO2 hydrates to carbonic acid
- KOH pathway - carbonic acid is neutralised
- KOH pathway - potassium hydroxide is regenerated
- NaOH pathway - CO2 neutralised, heat released
- NaOH pathway - sodium hydroxide is regenerated
- Sodium route - neutralisation (repeat)
- Sodium route - regeneration (repeat)
- Where to put the vaporizer: VOC vs VIC
- Vaporizer outside (VOC) versus inside (VIC) the circle
- Circle hazard 1 - compound A
- Circle hazard 2 - carbon monoxide
- Circle system - other practical issues
- Waters canister - the 'to-and-fro' system
- The Waters canister ('to-and-fro') system
Bringing it together
Choosing and comparing systems
- Summary - advantages and disadvantages
- Key takeaways
- Key-point marker used throughout the source text
- If the inner (fresh-gas) tube of a coaxial Bain disconnects at the machine end, what happens and what does the system become?
- References
- Essentials of Equipment in Anaesthesia, Critical Care, and Perioperative Medicine