Anaesthesia for eye surgery

A cataract is a cloudiness of the natural lens inside the eye that can blur vision. The most common eye procedure carried out is a cataract extraction and this is usually done under a local anaesthetic. Other, more difficult eye surgery such as retinal detachment, corneal grafts and glaucoma surgery are also usually done under local anaesthetic.

You may have trouble imagining having an eye operation under local anaesthesia but it is the most common way and has fewer risks and side effects than a general anaesthetic. Surgery of the cornea, such as laser surgery or removal of pterygiums or other lesions, can also be done just using local anaesthetic eye drops.

Types of anaesthetic

Local anaesthetic drops are special eye drops that will numb your eye. A local anaesthetic injection is used to numb an area around or behind your eye. This gives the best level of local anaesthesia for cataract and more difficult eye surgery. You stay awake but you are free from pain.

Sedation may be given if required. Sedation is a drug that gives you a ‘sleepy like’ feeling. It makes you feel very relaxed and comfortable.

Sometimes a general anaesthetic is needed. A general anaesthetic is a mixture of drugs to keep you deeply asleep and pain free during the operation. Drugs are injected into the bloodstream via a vein and/or breathed in as gases into the lungs. A breathing tube will be put into your throat or windpipe to help you breathe while under the anaesthetic. The tube is removed as you wake up after surgery.

What are the risks of the local anaesthetic?

Modern anaesthesia is generally very safe. Every anaesthetic has a risk of side effects and complications. Whilst these are usually temporary, some of them may cause long- term problems.

The risk to you will depend on:

• whether you have any other illness.

• personal factors, such as whether you smoke or are overweight.

• how simple or complex your surgery is.

• whether your surgery takes a short or a long time.

• whether your surgery is done in an emergency. Risks of a local anaesthetic injection for eye surgery

Common side effects and complications

• Mild bruising around the eye from the injection needle is common.

• Fuzzy or double vision

• Sagging of your upper eyelid.

Uncommon side effects and complications

• Bleeding or infection around your eye which may need further treatment.

• Damage to your eye and sight.

Rare risks

• Permanent partial or total sight loss

• Brainstem anaesthesia – this is where the local anaesthetic that has been injected spreads to your brain

• The needle may make a hole in your eye. This may require further treatment.

Risks of a general anaesthetic or sedation

Common side effects and complications

• Nausea or vomiting

• Headache

Pain and/or bruising at injection sites

• Sore or dry throat and lips

• Fuzzy/double vision and dizziness.

Less common side effects and complications

• Muscle aches and pains

• Weakness

• Mild allergic reaction - itching or rash

• Temporary nerve damage.

Uncommon side effects and complications

• Being awake under general anaesthetic

• Damage to teeth, dental work

• Damage to the voice box and cords, which may cause temporary loss or change of voice

• Allergic reactions and/or asthma

• Blood clot in the leg

• Damage to nerves and pressure areas

• Epileptic seizure

• Chest infection (more likely with smokers)

• Nerve damage due to pressure on a nerve during operation

• An existing medical condition getting worse.

Rare risks which may cause death

• Severe allergy or shock

• Very high temperature

• Stroke or heart attack

• Vomit in the lungs (pneumonia)

• Paralysis

• Blood clot in the lungs

• Brain damage.

Increased risks Risks are increased if:

− you are elderly

− smoke and

− are overweight. and if you have the following:

− A bad cold or flu, asthma or other chest disease

− Diabetes

− Heart disease

− Kidney disease

− High blood pressure

− Other serious medical conditions.

Your responsibilities before having a procedure

You are at less risk of problems from your anaesthetic if you do the following:

  1. When you have a local anaesthetic for eye surgery, it is very important for you to lie still and not move your head. Tell me if you have a cough or if you cannot control head movements.
  2. Increase your fitness before your surgery to improve your blood circulation and lung health.
  3. If you are overweight, reducing your weight will reduce many of the risks of having anaesthetic.
  4. Give up smoking at least 6 weeks before your surgery to give your lungs and heart a chance to improve. Smoking reduces the oxygen in your blood and increases breathing problems during and after an operation.
  5. Supplements and show your anaesthetist what you are taking.
  6. Drink less alcohol as alcohol may alter the affect of the anaesthetic drugs. Do not drink any alcohol 24 hours before the procedure.
  7. Stop taking recreational drugs before the surgery as these may affect the anaesthetic. If you have a drug addiction please tell your anaesthetist.

Your recovery

After the surgery you will be returned to the ward or Day Procedure Area where you will rest until you are recovered enough to go home.

Tell the nurse if you have any side effects from the anaesthetic, such as headache, nausea, or vomiting. The nurse will be able to give you some medication to help.

I will arrange your pain relief and any other medications you may need. Some ways of giving you pain relief are: • Tablets or pills – used for all types of pain. You need to be able to eat and drink and not feel sick for these to work. These take at least half an hour to work. • Injections – it is uncommon to need a strong pain relieving drug such as an injection for eye surgery.

Things for you to avoid after your anaesthesia

An anaesthetic will affect your judgment for about 24 hours. For your own safety:

• Do NOT drive any type of car, bike or other vehicle.

• Do NOT operate machinery including cooking implements.

• Do NOT make important decisions or sign a legal document.

• Do NOT drink alcohol, take other mindaltering substances, or smoke. They may react with the anaesthetic drugs.

• Have an adult with you on the first night after your surgery.