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The first 25 slides, exactly as they appear. The full deck has 102 content slides.
Anaesthesiology
The anaesthetic machine
Built from Al-Shaikh — Essentials of Equipment in Anaesthesia, Critical Care and Peri-operative Medicine, 6e
What’s inside
9 sections · 102 slides
Overview
- What the machine actually does
- The seven building blocks
- A modern continuous-flow anaesthetic machine
- The gas pathway from supply to patient
- Safety features built into a modern machine
Pressure gauges
Reading how much gas is in the cylinder or pipeline
- What a pressure gauge tells you
- Analogue pressure gauges on the machine
- Digital display of supply pressures
- The Bourdon gauge mechanism
- Inside the gauge, and how it moves
- Why the gauge can mislead — and its safety features
Pressure regulators
Reducing valves that create a steady working pressure
- Why we need regulators
- How a reducing valve works
- Cylinder regulators above the yokes
- A regulator with the tray removed
- Inside the regulator, and how it balances
- Problems and safety features
- Second-stage regulators and flow restrictors
- A flow restrictor
Flow control valves and flowmeters
Setting and measuring each gas flow
- The flow control (needle) valve
- Needle valve and flowmeter tube
- The flowmeter bank
- What a flowmeter is and how accurate it is
- Why the float rises: widening clearance
- How the float works
- Laminar vs turbulent: why viscosity AND density matter
- Reading the scale and float shapes
- Two flowmeters in series for low flows
- Reading, low flows and the oxygen minimum
- Section marker from the source text
- Flow control knobs: making oxygen unmistakable
- Colour-coded, distinctively shaped knobs
- Preventing hypoxia: the interactive O2/N2O link
- How a cracked flowmeter can cause hypoxia
- When flowmeters read wrong
Vaporizers
Adding a measured dose of inhalational agent
- What a vaporizer does, and the ideal one
- Two families of vaporizer
- A draw-over vaporizer
- A plenum vaporizer on the back bar
- Inside a plenum vaporizer
- Schematic of a plenum vaporizer
- The bimetallic strip
- How the splitting ratio makes a precise concentration
- Temperature compensation and altitude
- Selectatec back bar and its O-rings
- The Selectatec interlock
- Only one vaporizer can feed gas
- Mounting and interlock safety
- Vaporizer problems and safety features
- Filling devices: the right agent in the right vaporizer
- Agent-specific, colour-coded fillers
- Filler colour codes
- Non-return pressure relief valve
- The non-return pressure relief valve
Flush, alarms and gas outlet
The safety layer around the gas mixture
- The emergency oxygen flush
- The oxygen flush button and its valve
- Dangers of the oxygen flush
- Compressed oxygen outlet
- Compressed oxygen outlet
- The ideal oxygen-supply-failure alarm
- An oxygen-failure alarm
- How the fail-safe valve acts
- The pressure thresholds that protect the patient
- Anti-hypoxic features: three ways to guarantee oxygen
- The common gas outlet
- The common gas outlet
Desflurane and modern workstations
When a normal vaporizer will not do
- Why desflurane needs a special vaporizer
- A desflurane vaporizer
- Schematic of the desflurane vaporizer
- How the heated desflurane vaporizer works
- Electronic and integrated machines
- Aladin agent cassettes
- An integrated anaesthesia workstation
- The Aladin cassette (GE Aisys)
- A direct-injection workstation
- The Dräger Zeus IE workstation
- A non-ferrous MRI-compatible machine
- A compact anaesthetic machine
- MRI-compatible and compact machines
- A dental-style mixture machine
- The Quantiflex machine
- Break-before-make vaporizer selection
- The Glostavent Helix Duo for low-resource settings
Anaesthesia in remote areas
The Triservice apparatus
- The Triservice apparatus: compact field anaesthesia
- The Triservice apparatus
- How the Triservice apparatus works
- How it works and the OMV
- Triservice: problems and safety
Summary
Pulling the machine together
- The three jobs of the machine
- Key numbers to remember
- Why is oxygen always the last gas added to the mixture at the back bar?
- References
- Essentials of Equipment in Anaesthesia, Critical Care, and Perioperative Medicine