Pre-op guidance › Assessment & consent

Your anaesthetic assessment and consent

Before your operation you will meet your anaesthetist. This is a chance to check you are well prepared, answer your questions, and agree on the anaesthetic plan together.

Before the day - getting ready

Depending on your operation and your health, you may be asked to complete a health questionnaire, have some tests (such as blood tests or an ECG), or attend a pre-admission clinic. It helps to have ready:

• A current list of all your medicines, including doses (and anything from the chemist or health-food shop)
• Any allergies or past reactions to medicines or anaesthetics
• Any previous problems you or close family have had with anaesthesia
• Your major medical conditions and any specialists you see

Meeting your anaesthetist

On the day, your anaesthetist will review your health, examine you if needed (often your heart, lungs and airway), and talk through the plan for keeping you safe and comfortable. They will explain the type of anaesthesia suited to your operation - for example a general anaesthetic (fully asleep), a regional or spinal anaesthetic (numbing part of the body), sedation, or a combination - and how your pain will be managed afterwards.

Risks and questions

Every anaesthetic carries some risks. Most people have a smooth anaesthetic, and serious problems are uncommon, but your anaesthetist will discuss the risks that are relevant to you and your operation. There are no silly questions - it is completely reasonable to ask about anything that is on your mind.

Questions people often find useful to ask:

• What type of anaesthetic do you recommend for me, and why?
• How will my pain be managed after the operation?
• Are there any risks that particularly apply to me?
• How might I feel when I wake up, and how long will recovery take?

Consent to your anaesthetic

Consent means agreeing to go ahead with your anaesthetic once you understand what it involves. It is a conversation, not just a signature. The aim is for you to make a decision that is right for you, with the information and time you need.

As part of consent, your anaesthetist will usually explain:

• What is planned - the type of anaesthetic (general, spinal or epidural, sedation, nerve block, or a combination) and why it suits you and your operation.
• What it involves - what will happen as you go off to sleep or are numbed, what you might feel, and what to expect as you wake up.
• The benefits - good pain control, comfort, and safety during your surgery.
• The common side effects - such as nausea, drowsiness, a sore throat or shivering, which are usually short-lived and treatable.
• The risks relevant to you - more serious risks are uncommon and rare, and your anaesthetist will focus on the ones that matter for your health and your operation.
• The alternatives - where there is a reasonable choice (for example a spinal versus a general anaesthetic), so you can weigh them up.

You can ask as many questions as you like, ask for more information at any time, and you can change your mind - including on the day. Nothing will be done without your agreement. If you would prefer a family member or interpreter to be involved in the conversation, that can be arranged.

Putting the risks in perspective

It is natural to feel anxious about an anaesthetic. It can help to compare the risks to everyday risks we accept without much thought. For a fit and healthy person, the risk of dying as a direct result of an anaesthetic is very low - in the order of 1 in 60,000.

How likely is a problem? A scale of risk

Words like "rare" can mean different things to different people, so it helps to put numbers to them. The scale below is a rough guide to how often something happens.

• Very common - 1 in 10 (like one person on a busy bus).
• Common - 1 in 100 (like one person in a large lecture theatre).
• Uncommon - 1 in 1,000 (like one person in a small concert crowd).
• Rare - 1 in 10,000 (like one person in a full sports stadium).
• Very rare - 1 in 100,000 or less (like one person in a large city suburb).

Your own risk depends on your health, your age and your operation. Your anaesthetist will focus on the risks that actually matter for you.

Side effects and risks of a general anaesthetic

Very common and common (most settle quickly and are easily treated):

• Feeling sick or vomiting, and shivering or feeling cold.
• A sore throat, dry mouth, or hoarse voice.
• Drowsiness, dizziness, blurred vision and headache.
• Bruising or soreness where your drip or blocks were placed.
• Temporary confusion or memory problems, mainly in older people.

Uncommon:

• Minor damage to the lips or tongue, a chest infection, or aching muscles.
• Difficulty passing urine, or worsening of an existing medical condition.

Rare and very rare:

• Damage to teeth that needs a dentist (rare).
• Becoming aware during a general anaesthetic (around 1 in 19,000).
• A serious allergic reaction to a medicine (around 1 in 10,000), which the team is trained to treat.
• Nerve or eye injury, or a problem with the anaesthetic equipment (very rare).
• Death as a direct result of the anaesthetic is very rare - in the order of 1 in 100,000 in a fit and healthy person.

Some risks are higher if you smoke, are overweight, or have heart, lung, kidney or other health problems. Stopping smoking and being as active as you can beforehand both help.

Nerve blocks (regional anaesthesia)

Dr Halvey uses nerve blocks frequently. A nerve block is an injection of local anaesthetic placed near the nerves that supply the part of your body being operated on - often using an ultrasound machine to guide the needle accurately. It can be used for shoulder, arm, hand, hip, knee, leg, chest and abdominal surgery, on its own or alongside a general or spinal anaesthetic.

Why they are used:

• Excellent, targeted pain relief that can last many hours, and sometimes longer with a fine catheter and a small pump.
• Less need for strong opioid medicines, which means less nausea, drowsiness and constipation.
• Often a clearer head, earlier eating and drinking, and earlier movement and physiotherapy.

What to expect: the area becomes numb, heavy and weak - this is normal and expected. It wears off gradually over several hours (occasionally up to a day). While the limb is numb, take care to protect it from knocks, heat and pressure, and have your tablets ready for when the block wears off so there is no gap in your pain relief.

Risks of nerve blocks:

• Common: temporary numbness, heaviness or weakness; some bruising or soreness at the injection site.
• Uncommon: the block not working fully, so you need extra pain relief or a different technique.
• Rare: temporary nerve irritation, with tingling or numbness that lasts days to a few weeks and then settles; infection or bleeding at the injection site.
• Very rare: longer-lasting or permanent nerve damage (in the order of 1 in 2,000 to 1 in 5,000, and often related to the surgery itself rather than the block); local anaesthetic affecting the heart or brain if too much reaches the bloodstream, which the team is trained to manage. Blocks near the chest or neck can occasionally affect nearby structures and breathing - your anaesthetist will explain if this applies to your block.

Your anaesthetist will talk you through whether a nerve block is right for you and your operation.

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