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The first 25 slides, exactly as they appear. The full deck has 80 content slides.
Anaesthesiology
Medical gas supply
Built from Al-Shaikh — Essentials of Equipment in Anaesthesia, Critical Care and Peri-operative Medicine, 6e
What’s inside
8 sections · 80 slides
Overview
- What this topic covers
Cylinders
Storing gas safely under pressure
- What a cylinder is and why it must be strong
- Anatomy of a cylinder from the top down
- Nitrous oxide cylinder (size E)
- How much gas a cylinder holds
- Table of cylinder contents by size
- Size E oxygen cylinder
- Gas versus vapour - the idea that explains everything
- The four gas laws in plain words
- Why oxygen and nitrous oxide gauges read differently
- Cylinder pressure as contents are used (schematic)
- The filling ratio - why liquid cylinders are never full
- Testing and the marks stamped on every cylinder
- Reading the label before you use it
- Colour coding - a fast, universal safety cue
- Colour coding of common medical gas cylinders
- Storing and handling cylinders safely
Cylinder valves and pin-index
The gatekeeper on top of the bottle
- What the valve does
- Chemical formula engraved on a nitrous oxide valve
- Different types of cylinder valves
- A cylinder valve that opens and closes by hand
- The pin-index system
- Pin-index configurations differ for each gas
- Oxygen cylinder valve and pin index
- Nitrous oxide cylinder valve and pin index
- Carbon dioxide cylinder valve and pin index
- The Bodok seal - the small washer that seals the joint
- A Bodok seal
- Cylinder yoke with and without the Bodok seal
- Anaesthetic machine cylinder yokes
- Using the valve safely
Piped gas supply
Gas delivered to the wall at 400 kPa
- Why pipe gas around the hospital at all
- What the pipeline is made of
- Outlets and the Schrader probe
- Inserting a probe into a wall outlet socket
- Gas probes for oxygen, nitrous oxide and air
- Outlet sockets in a retractable ceiling unit
- Colour-coded hoses with non-interchangeable fittings
- Safety features and testing of the pipeline
- An area valve service unit
- Medical gas alarm panel
Sources of gas supply
Where the piped gas actually comes from
- Matching the source to the demand
- Two hospital sources of oxygen side by side
- The cylinder manifold
- An oxygen cylinder manifold
- Liquid oxygen and the VIE - the idea
- A vacuum-insulated evaporator
- How the VIE keeps itself cold and delivers gas
- Schematic of a liquid oxygen supply system
- Safety around liquid oxygen
- Oxygen concentrators - making oxygen from room air
- Portable home oxygen concentrator
- Anaesthetic machine with a built-in oxygen concentrator
- Hospital-scale oxygen concentrator
- How the concentrator cycles - and its limits
- Mechanism of action of an oxygen concentrator
Entonox
A ready-mixed analgesic gas
- What Entonox is and the Poynting effect
- Entonox cylinder with integrated demand valve
- Lamination - the cold-weather hazard of Entonox
- Preventing lamination and other precautions
Compressed air and medical vacuum
The other two pipeline services
- Compressed medical air
- Compressed medical air plant
- The centralised vacuum (suction) system
- Medical vacuum plant
- Vacuum performance and safety
Summary and self-assessment
Pulling the topic together
- The topic in three ideas
- Key-points marker used in the source text
- High-yield facts to remember
- Why does a nitrous oxide cylinder's pressure gauge stay almost unchanged until it is nearly empty?
- A patient using Entonox in a cold ambulance becomes hypoxic as the cylinder empties. Explain.
- References
- Essentials of Equipment in Anaesthesia, Critical Care, and Perioperative Medicine