General Anaesthetic

This document is intended to provide details about general anaesthetic. For more in-depth information, please contact your consultant. A general anaesthetic is used to put patients to sleep during surgical procedures so that they experience as little pain and distress as possible.

The medicines administered will:

  • Cause a deep and controlled sleep
  • Ensure pain relief
  • Prevent awareness and memory of the procedure

The general anaesthetic process

You will be asked to refrain from eating and drinking for a certain period of time before the anaesthesia is administered and your medical history will be checked to ascertain suitability for the procedure. Certain medical tests may be performed if your anaesthetist considers it necessary.

Most people undergo a general anaesthesia via a thin tube called a cannula. This will be inserted into a vein in the hand or arm. Sometimes anaesthetic gas is administered via a face mask. It takes around 30 seconds for the medicine to take effect. During surgery, an anaesthetist will constantly monitor the levels of anaesthetic to ensure that the right amount is maintained.

Other types of anaesthesia

Sometimes other types of anaesthesia are more suitable for a medical procedure. Regional or local anaesthetic can be used in some cases to numb certain areas of the body by injecting the anaesthesia into a specific area or near to a nerve or the spine. The difference is that with local anaesthetic you will be awake or under sedation throughout the surgery.

The risks of general anaesthesia

There are some risks associated with general anaesthesia and your consultant or nurse will explain them clearly to you. Many people undergo general anaesthetic every year with no problems at all.

Recovering from a general anaesthetic

Everyone recovers at different rates, but patients are advised it can take up to 24 hours to feel normal again following a general anaesthetic. You may experience some confusion or problems with coordination. Avoid driving, operating machinery or any strenuous physical activity. Additionally, avoid making important decisions in this period.


Most people have no problems after a general anaesthetic and it is usually a safe and effective way of enabling patients to undergo operations without pain.


References: EIDO Healthcare Limited – The operation and treatment information on this website is produced using information from EIDO Healthcare Ltd and is licensed by Aspen Healthcare.

The information should not replace advice that your relevant health professional would give you.