Anaesthesia for your surgery

You may be about to have surgery, and you likely came to this decision together with your whānau and your surgeon.

Before your surgery, you will be asked some questions. The hospital team caring for you needs to know more about your health and what support you have. They can then plan your surgical operation or procedure.

An anaesthetist who is part of the assessment clinic will usually read through your answers. An anaesthetist is a doctor who has specialised in keeping people safe and comfortable during surgery.

The anaesthetist or nurse might also phone you or ask you to come to hospital for an appointment. You may need to have more tests before your surgery, for example blood tests or scans, or be referred to other doctors who can help plan your surgical care.

They will work with you and your whānau to help you make a decision about whether you would like to have the surgery.

There are different ways that you can be kept safe and comfortable during your operation or procedure.

The anaesthetist will assess you and your health, and recommend the safest type of anaesthesia for the surgery you are having. This advice will be based on:

• the type of surgery
• your health and physical condition
• your past experiences with surgery and anaesthesia
• any reactions or allergies to medicines you have had
• the risks of each type of anaesthesia
• the preferences of you and your whānau.

Local anaesthesia

Local anaesthesia means you will have a numbing medicine injected where the surgery will be. This numbs that area so you feel no pain during surgery.

Local anaesthesia is a good option for some minor surgeries. You stay awake but should not feel pain.

It is used by many healthcare providers when taking biopsies, for example skin samples, and your dentist when working on your teeth. In hospital it is used for minor surgery. The numb feeling usually lasts a few hours.

Local anaesthesia can be given together with sedation.

Sedation

If you are having a procedure under sedation you will be given medicines that make you drowsy, relaxed and comfortable. Sedation is usually given as an injection into a vein, but it can be a tablet or a drink.

You will then be closely monitored throughout the procedure. Afterwards, it is common to have no memories, or only patchy memories, of the procedure.

To make sure you are comfortable, sedation is often given together with pain relief medicines, local anaesthesia or regional anaesthesia.

Regional anaesthesia

Regional anaesthesia also uses a local anaesthetic medicine, but the anaesthetist makes a much larger area of your body numb. They do this by injecting the anaesthetic around a nerve or group of nerves — which is why it is also known as a nerve block. This might mean your whole arm or whole leg is numb.

Regional anaesthesia can be for surgery or for pain relief.

Sometimes regional anaesthesia is a safer option than general anaesthesia. It can be the right choice if you would prefer to stay awake during surgery.

Your anaesthetist will let you know if regional anaesthesia is a good option for you.

There are 2 main types of regional anaesthesia:

• peripheral nerve block
• spinal and epidural.

Peripheral nerve block

A peripheral nerve block is when the anaesthetist makes a part of your body (such as your arm, leg or chest) numb for surgery. This can be made to last from several hours to several days, depending on what is needed.

Spinal anaesthesia

Spinal anaesthesia is a single injection into your lower back, between the bones of your spine. It makes your lower body numb — from your feet up to your chest — so you do not feel any pain during surgery.

It is often used in surgery on the uterus (such as a caesarean section), bladder, prostate, hips or knees.

The numbness typically lasts for several hours. You can remain fully awake or be given sedation to make you feel relaxed and comfortable.

Epidural

An epidural is very similar to spinal anaesthesia.

It is also an injection into your back, but usually a catheter (tube) is left in your back so more local anaesthetic can still be given. The catheter is very small and you can comfortably lie on it when it is taped to your back.

Instead of providing numbness for surgery, an epidural is more often used to provide pain relief over a longer time. It is used during labour and childbirth, and when recovering from surgery to the abdomen (puku).

An epidural catheter in your:

• lower back can help relieve pain in your legs and pelvis
• mid back can help relieve pain in your abdomen
• upper back can help relieve pain in your chest.

You can have sedation with regional anaesthesia to make you feel relaxed and comfortable.

General anaesthesia

General anaesthesia is when you ‘go to sleep’ for surgery. Your anaesthetist will stay with you, monitor you and make sure you are safe during your surgery.

For general anaesthesia, you will be given medicines that make you unconscious. This is different from normal sleep — you will not be able to wake as long as you are getting the anaesthetic medicines.

You are given the anaesthetic medicines in a vein or as a gas through a breathing tube. Your anaesthetist gives you just the right doses while monitoring you closely.

Modern general anaesthesia is very safe, but it has a some risks.

Anaesthesia is generally very safe. There are side effects that do happen quite often, like:

• having a dry throat
• feeling drowsy afterwards.

For most people, the risk of very serious side effects (adverse effects) is small. The risk depends on the type of anaesthetic you have and other health conditions you might have.

Adverse effects of anaesthesia

Common — between 1 in 10 and 1 in 100 people might have:

• sore throat
• nausea and vomiting
• aches, pains, headache or backache
• confusion
• difficulty passing wee (urine).

Uncommon — 1 in 1,000 people might have:

• an existing medical condition getting worse
• chest infection
• damage to teeth
• nerve damage to peripheral nerves (nerves outside of your brain and spine).

Rare — between 1 in 10,000 and 1 in 100,000 people might have:

• heart attack or stroke
• serious allergic reaction
• nerve damage to nerves in the spine
• damage to the eyes
• some memory of parts of the operation.

If you have medical conditions before your operation, the risk of the more serious events might be higher.

Your anaesthetist will discuss this with you and your whānau, including ways to reduce your risk.