Anaesthetics Overview

Anaesthetic— a description

An anaesthetic is a drug mixture that when administered, causes sensation loss. They are grouped into the following:

  • General anaesthetic:- induces a deep sleep. The patient is not aware of what happens at the time, and they will not remember the operation when then wake up.
  • Local anaesthetic:- a temporary measure to alleviate pain by stopping nerve function. The anaesthetic is injected around the area where you will have the operation. Another option is a nerve block, which numbs the nerves to the patient’s arm or leg.
  • Spinal or epidural anaesthetic:- injection of local anaesthetics and painkillers near the spinal cord, resulting in pain relief in certain areas of the patient’s body.

Your surgeon or anaesthetist will talk through the various options with you and recommend the best type, but it you will make the final decision about which anaesthesia you wish to receive. This document will provide details outlining the benefits and risks in order to help you in your decision, and let you make an informed choice. If you have questions that this document does not answer, it is recommended that you ask your surgeon, anaesthetist, or healthcare team.

The benefits of anaesthetics

  • If you suffer from a specific condition or are in pain, anaesthetics can provide pain relief. In this case, they will usually administered by an epidural.
  • In an operation or procedure, you will be required to be in a state where your muscles are relaxed and you are not moving. An anaesthetic is given to ensure this is achieved, so the surgeon or doctor can perform the procedure safely.

General anaesthetic

These are usually injected through a drip (small tube) into a vein. Within about 30 seconds, most people are asleep. Although the injection may ache slightly at the time, the uncomfortable feeling will often be gone by the time you wake up.

During your operation, more of the same anaesthetic is administered either by the drip or by anaesthetic gases in order to keep you asleep. Sometimes the anaesthetist may also administer further medication to limit any sickness or pain afterwards.

When the operation is over, the anaesthetic wears off, which enables you to wake up.

Local anaesthetic

It is possible to give different combinations of anaesthesia, so the operation can proceed with the smallest amount of discomfort to you. An example of this is a local anaesthetic being given to a patient before a general anaesthetic.

The simplest way to give a local anaesthesia is to inject it around the area which is going to have the procedure. It may burn or sting initially, but the area should go numb after a couple of seconds.

When it comes to nerve blocking, a combination of local anaesthetics and painkillers will be injected to the part of your body on which you be operated, near to the major nerves of this area.

Epidural anaesthetic

This will temporarily numb the nerves to give you pain relief. A fine tube called a catheter is inserted near into the epidural space near the spinal cord. Most of your nerves pass through this space. Once the catheter is in place, a mixture of painkillers and local anaesthetics are injected into the epidural space, and your nerves should be numbed.

Spinal anaesthetic

This technique is similar, but with a spinal anaesthesia you will only receive one injection. This is inserted into the bag of fluid surrounding the spinal cord.

Safety of anaesthetics

For most patients all types of anaesthesia are safe. If you require a general anaesthetic, it may be necessary to undergo a couple of tests before the operation, to see how safe this will be. These tests will allow the healthcare team to choose what other options are available and if they need to carry anything out differently.

The anaesthetist may also recommend that you see your GP, to discuss improving your medical condition beforehand. These include angina, asthma, anaemia or high blood pressure.


Anaesthesia in its different forms can be used to provide a safe and effective way for you to undergo a operation, as well as giving you the necessary pain relief. An awareness of them will also help you to detect and treat any potential problems at an early stage. Complications can occur, although usually people do not have any issues and are satisfied with the anaesthetic. In order to make an informed decision about an anaesthetic, it is important that you are aware of these complications.



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