This section explains what sedation is, how it works and when you may need it. It also explains the benefits and risks of using sedation and what it might feel like. Importantly, it tells you what you will need to plan for your care after sedation
Sedation is usually given into your vein (IV or intravenous) but can sometimes be given by mouth (oral) or through a face mask.
What is intravenous sedation?
Intravenous sedation is when a sedative (sedation medicine) is injected into your bloodstream (vein) through a drip (tube) to relax you. In the operating theatre, the anaesthetist would administer the sedatives for the patients.
There are three different levels of intravenous sedation. They are called ‘minimal’, ‘moderate’ (sometimes also called conscious sedation) and ‘deep’ sedation.
- Minimal sedation – a small amount of sedative would be given. You will feel relaxed and less worried by what is happening around you, but you will be awake and able to talk normally. You are likely to remember having your treatment, but not all the detail. Minimal sedation should not affect your breathing.
- Moderate sedation (conscious sedation) – you would be given a little more sedative(s) so you will feel very relaxed and drowsy. Importantly though, you can still communicate with the staff around you and you will still be able to follow simple instructions. You may remember some parts of your treatment. Moderate sedation should not affect your breathing.
- Deep sedation – a higher dose of one or more drugs would be given to make you sleep during most of your treatment. Your doctor will not expect to talk to you during your treatment. Your breathing may be affected, and your anaesthetist will watch and help you if needed. You may sometimes remember part of your treatment
What is oral sedation?
This can sometimes be useful to relax very anxious people before a general anaesthetic, but it is usually not enough to relax you during a procedure on its own. It takes a while to work and it can be difficult to get the right dose as it varies between people.
What are the differences between sedation and general anaesthesia?
The main differences between sedation and general anaesthesia are:
- your level of consciousness
- the need for equipment to help support your breathing
- possible side effects.
With minimal and moderate sedation, you feel drowsy, comfortable, sleepy and relaxed, but you remain conscious throughout the procedure. With general anaesthesia you are completely unresponsive and unconscious during the procedure. Deep sedation is between the two.
What treatments can be carried out under intravenous sedation?
Many minor treatments can be undertaken with intravenous sedation. A few examples include:
- skin or breast biopsies
- minor repair to fractured bones
- minor surgery to the skin, hand or foot
- procedures to help diagnose problems with the stomach (endoscopy), the lung (bronchoscopy), the colon (colonoscopy) or the bladder (cystoscopy)
- removal of teeth or other dental treatment
- eye operations, such as cataract removal.
- injections to the spinal nerve roots and facet joints
What are the benefits of intravenous sedation?
- It is quick acting, and the dose can be adjusted quickly so you get just the right amount.
- It allows you to be more relaxed during your treatment. It may also mean that you remember very little about your treatment afterwards.
- For some procedures, it avoids the need for a general anaesthetic which may be unsuitable for patients with some medical problems.
- It usually has fewer side effects than a general anaesthetic.
- Recovery is quicker than after a general anaesthetic, so you can usually go home earlier.
What are the risks of intravenous sedation?
- Your breathing rate may become slow. This is common in deep sedation, but is a risk whenever sedation is used. The anaesthetist is skilled in monitoring you and can assist your breathing if required.
- It is common for your blood pressure to drop, but the anaesthetist is trained in treating this too.
- Feeling sick or vomiting can happen but is uncommon.
- Any allergic reaction to the sedation drugs is very rare.
- You may have a small bruise where your cannula was placed or attempted.
- Afterwards you may feel less steady on your feet and you may be at higher risk of falling, especially if you are elderly.
- Sedation can affect your judgement and memory for up to 24 hours.
What are the alternatives to sedation?
- A general anaesthetic: you will be fully unconscious throughout and have no memory of the procedure.
- Local anaesthetic without any sedation: you will be fully awake during your treatment, but will be comfortable.
Who decides whether I can have sedation?
You can discuss the option of sedation with your doctor at the time of assessment. If it has not been offered, you can always ask to see if it is possible to have it. If you are at higher risk from existing medical conditions, your doctors will discuss the options with you, and you can reach a decision together.
I am having sedation, what should I do before I come to the hospital?
- If you have people that you look after, for example children or old people, you will need to plan for someone else to look after them until the next day.
- A capable adult will need to take you home by car or taxi – ideally not public transport. As the effects of sedation can last up to 24 hours, they should stay overnight to look after you.
- Take all your medicines to hospital with you, including any inhalers you use.
- If you have an illness, a cold or you are pregnant, please contact your hospital as it may not be safe to have sedation. Your treatment may have to be re-arranged.
- Let your doctor know on the day of the procedure if you are breastfeeding.
- Remove all makeup – including nail varnish and jewellery – before coming to hospital. You may wear a wedding band.
Can I eat and drink before my treatment?
The clinic or hospital will give you instructions on when to stop eating and drinking. You will usually be asked to stop eating six hours before your treatment. If you have diabetes, you should ask for specific instructions about when you should take your medication and stop eating food.
Side-effects, complications and risks
In modern anaesthesia, serious problems are uncommon. Risk cannot be removed completely, but modern drugs, equipment and training have made anaesthesia a much safer procedure in recent years. Anaesthetists take a lot of care to avoid all the risks outlined in this section. Your anaesthetist will be able to give you more information about any of these risks and the precautions taken to avoid them.
Contributed by Dr Cheong Keng Fatt, Consultant Anesthetist
Adapted from Royal College of Anaesthetists, UK