Anaesthetic machine

Anaesthetic_machine

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  Maquet Flow-I anesthesia machine
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  Cyprane Trilene inhaler
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  Vaporizer
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  Anaesthetic machine
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  Adjustable pressure-limiting valve on anaesthetic machine

Anaesthetic Machine

An anaesthetic machine is a medical device used to generate and mix a fresh gas flow of medical gases and inhalational anaesthetic agents for the purpose of inducing and maintaining anaesthesia. The machine delivers a controlled flow of oxygen, nitrous oxide, and other gases to the patient, along with volatile anaesthetic agents, to ensure the patient remains unconscious and pain-free during surgical procedures.

Components

The anaesthetic machine consists of several key components:

Gas Supply

The gas supply system provides the necessary gases, such as oxygen, nitrous oxide, and sometimes air, to the anaesthetic machine. These gases are typically stored in high-pressure cylinders or supplied via a central pipeline system.

Flowmeters

Flowmeters are used to control and measure the flow rate of each gas. They ensure that the correct mixture of gases is delivered to the patient. Each gas has its own flowmeter, and the flow rates are adjusted using control knobs.

Vaporizers

Vaporizers are devices that convert liquid anaesthetic agents into vapors, which are then mixed with the fresh gas flow. Common inhalational agents include isoflurane, sevoflurane, and desflurane. Vaporizers are calibrated to deliver a precise concentration of anaesthetic vapor.

Breathing Circuit

The breathing circuit connects the anaesthetic machine to the patient. It includes components such as the breathing tubes, reservoir bag, and patient interface (such as a mask or endotracheal tube). The circuit allows for the delivery of anaesthetic gases and the removal of exhaled gases.

Ventilator

The ventilator is an integral part of the anaesthetic machine, providing mechanical ventilation to the patient. It ensures adequate ventilation by delivering breaths at a set rate and volume, especially when the patient is unable to breathe spontaneously.

Scavenging System

The scavenging system is responsible for collecting and removing excess anaesthetic gases from the operating room environment, preventing exposure to healthcare personnel.

Function

The primary function of the anaesthetic machine is to deliver a precise mixture of gases and anaesthetic agents to the patient. The machine allows for the control of:

• The concentration of oxygen and other gases.
• The concentration of inhalational anaesthetic agents.
• The rate and volume of ventilation.

The anaesthetic machine also includes safety features such as alarms and monitors to ensure patient safety during anaesthesia.

Safety Features

Anaesthetic machines are equipped with various safety features to prevent accidents and ensure patient safety:

• Oxygen failure alarm: Alerts the operator if the oxygen supply is interrupted.
• Hypoxic guard: Prevents the delivery of a hypoxic gas mixture by ensuring a minimum concentration of oxygen.
• Pressure relief valves: Protect the patient from excessive pressure in the breathing circuit.

Related Pages

• Anaesthesia
• Inhalational anaesthetic
• Mechanical ventilation
• Patient monitoring