Video: What is anaesthesia?
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(ANZCA, 2018)
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(ANZCA, 2018)
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Anaesthetics temporarily block the nerve signals that keep you awake and aware from reaching your brain. This means procedures can be done without you feeling anything. After the anaesthetic wears off, the nerve signals reach your brain and feeling will return to the affected part of your body.
(Steven Zheng, TedEd, 2015)
There are three main types of anaesthesia: local, regional and general. Sedation (see below) is sometimes used with local and regional anaesthesia to help relax you or make you sleep.
Local anaesthesia is used to numb a small part of your body while you are awake. It is used for minor procedures. This anaesthetic can be given as an injection or as a spray, cream or gel that is put on the area.
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(Swansea Bay NHS TV, UK, 2020)
Regional anaesthesia is used to numb a larger part of your body. This anaesthetic is given as an injection around specific nerves. Regional anaesthesia allows you to stay awake. There are two types of regional anaesthesia:
General anaesthesia is used to keep you unconscious during surgery, so you will feel nothing and have no memory of what happens during your surgery. Your awareness will return when the effects of the anaesthesia wares off. General anaesthesia is given as a gas that you breathe into your lungs and as an injection through a vein. While you are under a general anaesthetic a breathing tube is put into your windpipe to help you breathe. The tube is removed as you wake up after surgery. General anaesthesia is used for many operations such as surgery on your heart, lungs, and abdomen.
Sedation involves using small amounts of anaesthetic medication to make you relaxed and sleepy, but not unconscious. Many people having local or regional anaesthesia do not want to be awake for the surgery so they choose to have sedation as well. If you have sedation, you will remember little or nothing of the operation. It does not always mean you will have no memory of the operation. Only a general anaesthetic can do that.
The type of anaesthesia used will depend on the type of procedure or surgery, your health such as heart disease or diabetes and the results of tests, such as blood tests or an electrocardiogram (ECG).
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You may be having a baby and may need anaesthesia. Watch the video below about anaesthesia and having a baby.
(ANZCA, 2021)
Anaesthetists are doctors who have specialist training in anaesthesia. Before the procedure, your anaesthetist will discuss the best types of anaesthetic for the procedure. They'll plan your anaesthetic and pain control with you, including any preferences you have. Your anaesthetist will carefully monitor you during your operation and make sure you wake up comfortably afterwards. They may also help with pain relief after the procedure.
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(ANZCA, 2016)
Like all medicines, anaesthetics can cause side effects, but they don't last very long. Common side effects of general anaesthesia and some of regional anaesthesia include:
Usually having anaesthesia is safe and major problems are rare. Your risk depends on the type of anaesthesia you get, your age, your health, and how you respond to the medicines. Some health problems, such as heart or lung disease, increase your chances of problems from anaesthesia. Being overweight, taking certain medicines, smoking and using illegal drugs can also increase your chance of problems. Your anaesthetist will talk with you about the best type for you and will review risks, benefits and other choices.
Possible complications include allergic reaction, permanent nerve damage, heart attack, stroke, organ failure, reawakening during a procedure and the risk of dying. Complications are more likely in the very young, the elderly and people with other health problems. For a fit person under 60 years of age, the chance of dying due to an anaesthetic complication is approximately 1 in 1 million. The risk for people over the age of 60 can be higher depending on other health conditions.
Your doctor will let you know what to do the night before and on the day of the procedure. Here are some tips to help you prepare:
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(ANZCA, 2019)
The following links provide further information about anaesthesia. Be aware that websites from other countries may have information that differs from New Zealand recommendations.
Anaesthetics and asthma fact sheet(external link) Asthma + Respiratory Foundation NZ
About anaesthesia(external link) The Australian and New Zealand College of Anaesthetists (ANZCA)
Anaesthesia(external link) NHS Choices, UK, 2015
Anaesthetics and asthma fact sheet(external link) Asthma + Respiratory Foundation NZ, 2010
What is anaesthesia?(external link) ANZCA
Types of anaesthesia(external link) ANZCA
Asthma + Respiratory Foundation NZ, 2010
Credits: Healthify editorial team. Healthify is brought to you by Health Navigator Charitable Trust.
Reviewed by: Angela Lambie, Pharmacist, Auckland
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