What is ‘Anaesthesia’?

The word ‘Anaesthesia’ means ‘loss of sensation’.

• It stops the Patient from feeling pain and other sensations.
• It can be given in various ways.
• Not all anesthesia makes the patient unconscious.
• It can be directed to different parts of the body.

Drugs that cause anesthesia work by blocking the signals that pass along Patient nerves to the Patient's brain. When the drugs wear off, the patient starts to feel normal sensations again, including pain.

Some types of anesthesia

Local anesthesia

A local anesthetic numbs a small part of the Patient’s body. It is used when the nerves can easily be reached by drops, sprays, ointments, or injections. The patient stays conscious but free from pain.

Regional Anaesthesia

Regional anesthesia can be used for operations on larger or deeper parts of the body. Local anesthetic drugs are injected near to the bundles of nerves which carry signals from that area of the body to the brain.

The most common regional anesthetics (also known as regional ‘blocks’) are spinal and epidural anesthetics. These can be used for operations on the lower body such as Caesarean sections, bladder operations, or replacing a hip joint. The patient stays conscious but free from pain.

General Anaesthesia

General anesthesia is a state of controlled unconsciousness during which the Patient feels nothing and may be described as ‘anesthetized’. This is essential for some operations and may be used as an alternative to regional anesthesia for others. Anesthetic drugs injected into a vein, or anesthetic gases breathed into the lungs, are carried to the brain by the blood. They stop the brain from recognizing messages coming from the nerves in the body.

Anaesthetic unconsciousness is different from unconsciousness due to disease or injury and is different from sleep. As the anesthetic drugs wear off, the Patient’s consciousness starts to return.

Combining types of anaesthesia

Anesthetic drugs and techniques are often combined.

For example:

• A regional anesthetic may be given as well as a general anesthetic to provide pain relief after the operation.
• Sedation may be used with a regional anesthetic. The regional or local anesthetic prevents the Patient from feeling pain, and the sedation makes the patient feel drowsy and mentally relaxed during the operation.

Sedation

Sedation is the use of small amounts of anesthetic