Fig. 83.1
Schematic diagram of an anesthesia machine
- 1.
what is section A and what are its components?
- 2.
What are the safety systems in the high-pressure system, and what is the pressure for the different gases in the high-pressure system?
- 3.
What is section B and what are its components?
- 4.
What is section C and what are its components?
- 5.
What is a fail-safe valve and what is its function?
- 6.
What are the mechanisms used to prevent delivering a hypoxic mixture at the fresh gas outlet?
- 7.
What is the oxygen flush valve? What are the properties of the oxygen coming through the oxygen flush activation and what are the disadvantages?
- 8.
How is the leak test performed?
- 9.
How do we determine the presence of an oxygen pressure failure safety device or fail-safe valve?
- 10.
What is an oxygen supply failure alarm?
Answers
- 1.
This is the high-pressure system (cylinder to pressure regulators) in the anesthesia machine. Its components are:
Hanger yoke, which includes the filter and unidirectional valve
Yoke block
Cylinders with safety features and pressure gauge
Cylinder pressure regulators
- 2.
Cylinder pressure can increase due to defective overfilling or when cylinders are exposed to high temperature. The increase in pressure can cause the cylinder to explode. Rupture disk device in the cylinder plays a safety role by rupturing the disk when the pressure in the cylinder increases beyond the safety range expelling the contents thereby avoiding an explosion. Thermally controlled fusible plug melts and releases the gas under high pressure due to expansion of gases when cylinders are exposed to higher temperature [1].
Working pressure for the different gases in the high-pressure system are:
Oxygen 1900 psig
Nitrous Oxide 745 psig
Air 1900 psig upstream of the pressure reducing valve
- 3.
This is the intermediate pressure system (from pressure regulators to the flowmeter). Components include:
Pipeline inlets for oxygen, nitrous oxide and air.Full access? Get Clinical Tree