What is Anaesthesia?

The word anaesthesia means ‘loss of sensation’. Anaesthesia refers to the administration of medications either by injection or by inhalation (breathing in) that block the feeling of pain and other sensations.

Anaesthesia can range from a simple injection of local anaesthetic to numb a small area of the body, such as a finger or a tooth, to the use of powerful drugs that cause unconsciousness.

These powerful drugs also affect the function of the heart, the lungs and the circulation. As a result, anaesthesia is only administered under the close supervision of an anaesthetist who has been trained to consider the best way to give you an effective anaesthetic while keeping you safe and well.

Australia is one of the safest places in the world to have a general anaesthetic.

Types of Anaesthesia


Sedation is used for procedures where general anaesthesia is not required. It allows patients to tolerate procedures that would otherwise be uncomfortable or painful. It may be associated with a lack of memory of events.

Regional Anaesthesia

Regional anaesthesia includes ‘nerve blocks’, ‘epidurals’ and ‘spinal blocks’. These involve the injection of local anaesthetic near major nerve bundles that supply an area such as the ankle, foot, shoulder, forearm or hand.

Regional anaesthesia is often achieved using either an ultrasound and/or a painless nerve-stimulating device. These devices allow the precise location of the selected nerves to improve the accuracy and safety of regional anaesthesia.

Once the local anaesthetic has been injected into the desired location, patients may experience numbness and tingling in the area, and it may become difficult or impossible to move that part of the body. Regional anaesthetics are also useful for pain relief after an operation as the area will stay numb for a number of hours. Once the local anaesthetic wears off, sensation will return to normal.

Regional anaesthesia may be used on its own or in combination with sedation or general anaesthesia.

Local Anaesthesia

Local anaesthesia involves the injection of local anaesthetic near the surgical site and is usually used for minor surgery. It may be used on its own or in combination with sedation or general anaesthesia.

General Anaesthesia

General anaesthesia produces a drug-induced state where the patient is unconscious and will not respond to any stimuli including pain. It results in changes in breathing and circulation which will be monitored closely by your anaesthetist to ensure your safety.

For more information:
ANZCA - Patient Information
ASA - Patients