ANAESTHESIA FOR MAJOR JOINT REPLACEMENT
A Guide for Patients
The Basford Consulting Rooms has a number of Orthopaedic Surgeons and Anaesthetists who specialise in Joint Replacement Surgery.
Joint replacements are usually performed for arthritis associated with wear and roughening of the joint. It is a major operation and one that requires an anaesthetic. There are various types of anaesthesia and each technique has an advantage over the other depending on various factors.
· a general anaesthetic
· a spinal anaesthetic
· an epidural anaesthetic
· a nerve block (to help with pain afterwards)
· A combination of anaesthetic techniques.
Your anaesthetist will explain which anaesthetic methods are suitable for you, and help you decide which you would prefer.
A General Anaesthetic
A general anaesthetic gives a state of controlled unconsciousness during which you feel nothing.
You will receive:-
· anaesthetic drugs (an injection or a gas to breathe)
· strong pain relief drugs (morphine or something similar)
· oxygen to breathe
· sometimes, a drug to relax your muscles.
You will need a breathing tube in your throat to make sure that oxygen and anaesthetic gases can move easily into your lungs. If you have been given drugs that relax your muscles, you will not be able to breathe for yourself and a breathing machine (ventilator) will be used.
When the operation is finished the anaesthetic is stopped and you regain consciousness.
You will be unconscious during the operation.
A general anaesthetic alone does not provide pain relief after the operation. You will need strong pain relieving medicines afterwards which make some people feel quite unwell. Or you may wish to consider a nerve block with a general anaesthetic (see below).
A Spinal Anaesthetic
This is done by injecting a local anaesthetic near to the nerves in your lower back.
· You go numb from the waist downwards
· You feel no pain, but you remain conscious
· If you prefer, you can also have drugs which make you feel sleepy and relaxed (sedation).
Advantages – compared to a general anaesthetic
· It helps to avoid blood clots in the legs and lungs.
· There may be less bleeding during surgery and you may be less likely to need a blood transfusion.
· You remain in full control of your breathing. You breathe better in the first few hours after the operation.
· You do not need so much strong pain relieving medicine in the first few hours after the operation.
· You should have less sickness and drowsiness after the operation and may be able to eat and drink sooner.
· Headache - When the spinal wears off and you begin to move around there is a small risk of developing a headache.
· Low blood pressure. This can be easily treated by your anaesthetist
· Itching –If you experience itching it can be treated, as long as you tell the staff when it occurs.
· Difficulty passing water (urinary retention) - You may find it difficult to empty your bladder normally for as long as the spinal lasts. Your bladder function returns to normal after the spinal wears off.
· Nerve damage –This is a very rare complication of spinal anaesthesia. Permanent nerve damage is even rarer and has about the same chance of occurring as major complications of general anaesthesia.
An Epidural Anaesthetic
A small plastic tube (an epidural catheter) is passed through a needle into a place near to the nerves in your back. You receive local anaesthetics and pain relief drugs through this tube, relieving pain and reducing all feeling in your lower body.
Although operations can be done with an epidural alone, it is more commonly used for:
· operations expected to be very long, say more than 3 hours
· operations expected to be particularly painful afterwards.
For these operations, it is often combined with a spinal or a general anaesthetic.
· It can be topped up with more local anaesthetic, and therefore its effects can be made to last longer than a spinal anaesthetic.
· It can be used to make you comfortable for several days after the operation.
· About 1 in 10 epidurals is not fully effective in relieving pain after the operation.
· All the side effects and complications described can occur without an epidural.
· Side effects are common, are often minor and are usually easy to treat. Serious complications are fortunately rare.
· For major surgery, the risk of permanent nerve damage is probably about the same, with or without an epidural.
A Nerve Block
This is an injection of local anaesthetic near to the nerves which go to your leg or arm. Part of your leg/arm should be numb and pain-free for some hours afterwards. You may also not be able to move it properly during this time.
If you are having a general anaesthetic, this injection may be done before the anaesthetic starts, or it may be done when you are unconscious.
· You usually need a lighter general anaesthetic and you should be less sick and drowsy afterwards. This is because you should need less strong pain relieving medicines during and after the anaesthetic.
· You should be more comfortable for several hours after the operation.
A combination of anaesthetics
You can have a spinal or epidural anaesthetic and a general anaesthetic together.
· You gain the benefits of a spinal or epidural anaesthetic but you are unconscious during the operation.
· Unpleasant after-effects of the general anaesthetic may be less.
You can have a nerve block with a general anaesthetic, or after a spinal anaesthetic.
· You should be more comfortable for some hours after the operation than with a general anaesthetic or spinal anaesthetic alone.
· Before your operation
You will generally be called up to hospital about two weeks before the proposed date of your operation. This allows doctors and nurses to check to see if you are medically fit for the anaesthetic and operation. Fresh x-rays and blood tests may be taken.
You will be questioned about your current health and past medical, surgical or medication history. Particularly important things to tell the nurse or doctor about are:
· Previous heart problems
· any particular shortness of breath problems
· any bad reactions to a previous anaesthetic
This is an opportunity to tell the nurse of any worries or special needs when you return home after your operation. The operation cannot be performed if there are any active infections. If any infections, including a bad cold occur after your assessment but before your admission, please telephone the Admissions Officer or your Surgeon’s Secretary.
You must bring all your current medicines prescribed by your doctor to the Assessment Clinic and on admission to the ward. Smokers must stop prior to surgery to lessen the likelihood of a post-operative infection thrombosis and other complications.
After Admission to Hospital
After you are admitted you may, be visited by a physiotherapist or nurse who will advise you of simple muscle bracing exercises and breathing exercises to do before and after your operation. Any special post-operative exercises or rehabilitation needs will be indicated.
You will be asked to remove any make-up or nail polish and all jewellery except for a wedding ring. The nursing staff will ensure you have a complete all over shower (as your physical limitations allow) using an antiseptic soap. Your pre-medication (if prescribed by the anesthetist) will be administered.
The side of the operation will be marked and/or a label affixed to you detailing the procedure to be undertaken. You will be carried on a trolley or bed to the theatre.
You can wear your hearing aid, glasses and dentures until you are in the anaesthetic room. If you are not having a general anaesthetic, you can usually keep them on during the operation.
Nothing to eat or drink – fasting (‘nil by mouth’)
It is essential that you do not have anything to eat, drink or chew for some hours before your operation, as this could cause vomiting while you are under the anaesthetic. The nurses looking after you should give you clear instructions about fasting. It is important to follow these. If there is food or liquid in your stomach during your anaesthetic, it could come up into the back of your throat and damage your lungs.
If you are not having a general anaesthetic, you will still be asked to follow these instructions. This is because a general anaesthetic may be needed unexpectedly and you need to be prepared.
The anaesthetist’s visit
The anaesthetist will come and see you before your operation. He or she will ask you about your health and discuss which kinds of anaesthetic are suitable for you. This is the time to ask any questions about the anaesthetic. Your Anaesthetist will be able to advise you of which technique might be more suitable for you, taking into account your general health.
The anaesthetist will ask you about:-
· your general health and fitness
· any serious illnesses you have had
· previous anaesthetics and if there were any problems as far as you know
· whether you know of any family members who have had problems with anaesthetics
· medicines, pills, inhalers or homeopathic remedies that you use
· any allergies that you have
· whether you smoke
· whether you drink alcohol
· whether you have any loose, capped or crowned teeth.
Having a ‘premed’ (pre-medication)
This is the name for drugs which are sometimes given before an anaesthetic. The Anaesthetist may recommend a pre-medication to be given some hours before surgery. This is an injection or tablet that will make your wait less anxious.
· A premed is not always necessary.
· Some premeds prepare your body for the anaesthetic, for example, drugs to prevent sickness or to reduce the acid in your stomach.
· You can also ask for a drug which makes you feel drowsy and helps you relax. If you think that this kind of premed will help you, please ask your anaesthetist.
Your usual medicines
It is important that you continue to take your usual medicines, including inhalers, unless your surgeon or anaesthetist has advised you not to.
The Anaesthetist will also advise you of any other special techniques, which might be necessary for you and give you an indication of any particular risks regarding your general state of health.
Your preferences are important. Nothing will happen to you until you understand and agree with what is planned for you. You have the right to refuse if you do not want the treatment suggested.
Delaying your operation
Your anaesthetist may suggest delaying your operation for a few weeks. This may be because he/she thinks that:-
· you need some more tests.
· your health could be improved to reduce the risks of the operation or the anaesthetic.
It is possible that your anaesthetist will think there are very high risks. You may want time to think about whether to go ahead with the operation. These concerns will also be discussed with your surgeon.
The Anaesthetic Room
You will then be taken through to the Anaesthetic Room. Several people will be there, including your Anaesthetist and an anaesthetic assistant.
The Anaesthetist will use equipment to measure:
· your heart rate - 3 sticky patches on your chest (electrocardiogram or ECG)
· your blood pressure – a cuff on your arm
· the oxygen level in your blood – a clip on your finger (pulse oximeter)
A needle is used to put a thin soft plastic tube (a cannula) into a vein in the back of your hand or arm. Drugs and fluids can be given through this cannula.
Once asleep you will be moved into Theatre and your Consultant will perform your operation for you. You will only be woken up when it is all finished.
During the operation
All anaesthetics may cause changes in
· your heart rate
· your blood pressure
· your breathing.
Changes may also occur due to loss of blood, the use of surgical cement and the use of a tourniquet on your leg/arm.
Your Anaesthetist may intentionally adjust your blood pressure and breathing to control your response to surgery. Anaesthetic drugs are given continuously throughout surgery and are stopped when the operation ends.
You may lose a significant amount of blood during and after the operation.
· A blood transfusion can be used to replace the blood you have lost.
· Usually this is blood from a volunteer who has given blood to help others (a blood donor).
· A blood transfusion will not be recommended unless you have a significantly low blood count.
· It may be possible to collect blood that is lost during the operation and afterwards from the drain that the surgeon places in your leg. This blood can be given back to you through your drip.
· Please ask your Surgeon or Anaesthetist if you would like to know more about blood transfusion and any alternatives there may be.
You will be taken to the recovery room, which is near to the operating theatre.
· You will have your own nurse in the recovery room. You will not be left alone.
· There will be other patients in the same room.
· You may need to breathe oxygen through a light plastic mask.
· You will have a drip in your arm to ensure you get enough fluids.
· The nurses will continue to check your blood pressure regularly as required.
· You will have close monitoring by a nurse who will also help you to move in bed to change position, so relieving any pressure points.
· If you have pain or sickness, the nurse will treat it promptly.
When the recovery room staff are satisfied that you have recovered safely from your anaesthetic you will be taken back to the ward
Post operative Ward - Room
You may eat and drink as you feel able. However, you may feel a little under the weather and not have much of an appetite. This is quite normal and your appetite will return over the next few days.
Although you may find you are able to move independently, the nurses will help you change position to relieve any pressure points as it is still important to keep you on the move every couple of hours. You must call the nurse if you need help more often or if you need anything at all.
Your temperature will be checked every four hours or so. This shows us whether you have any infection or reactions following your operation,
Dressings are usually checked every day and if clean and dry will not be disturbed.
What to Expect After Surgery
You will have some discomfort or pain after surgery. The nursing staff will assist you to control any pain through injections or tablets.
If you have pain; please ask for painkillers - they will be offered to you when the nurse in charge goes round with the drug trolley, but you must feel free to ask at anytime - pain does not always coincide with the times that we do a drug round.
Your Anaesthetist will discuss the best method of controlling your pain with you. There is a form of pain relief available called a PCA (Patient Controlled Analgesia). This means you will have a pump, which you control yourself to administer small doses of painkiller by pressing a button on the handset whenever you need more pain relief. It is very safe and you will be closely monitored by nursing staff.
Another form of pain relief is an epidural. The Anaesthetist inserts a thin hollow needle into the epidural space, just outside the outer covering of the spinal cord in the lower back. A small plastic tube is then introduced through the needle and left in position when the needle is removed. The tube is used to introduce local anaesthetic and pain killing medication. Staff will be happy to help you in any way to make your stay as comfortable as possible.
Good pain relief is important and some people need more pain relief medicines than others.
Here are some ways of giving pain relief:-
Pills, tablets or liquids to swallow
These take at least half an hour to work and you need to be able to eat and drink and not feel sick for these drugs to work.
These waxy pellets are placed in your back passage (rectum). They are useful if you cannot swallow or might vomit and are highly effective at controlling pain
These are given into a vein for immediate effect, or into your leg or buttock muscle. Strong pain relieving drugs such as morphine, pethidine and codeine may be given by injection.
Patient controlled analgesia (PCA)
This is a method using a machine that allows you to control your pain relief yourself. Small doses are given into a vein for immediate effect.
Nerve blocks and epidurals
As already described, these can give effective pain relief for hours or days after the operation.
Side-effects, complications and risks
In modern anaesthesia serious problems are uncommon. Risk cannot be removed completely, but modern equipment, training and drugs have made anaesthesia a much safer procedure in recent years.
Common and very common side effects
· Pain around injection sites and general aches and pains
· You may not be able to pass water (urine) or you may wet the bed. This is because you are lying down, you may have pain and you may have received strong pain relieving drugs. A soft plastic tube may be put in your bladder (a catheter) to drain away the urine for a day or two. This is more common after spinal or epidural anaesthetics.
Spinal or epidural anaesthetics
· You will not be able to move your legs properly for a while.
· If pain relieving drugs are given in your spinal or epidural as well as local anaesthetic, you may feel itchy.
· Sickness – treated with anti sickness drugs
· Sore throat – treated with pain relief drugs
· Drowsiness, headache, shivering, blurred vision – may be treated with fluids or drugs
· Difficult breathing at first – this usually improves rapidly
· Confusion and memory loss are common in older people, but are usually temporary.
Uncommon side effects and complications
· Heart attack or stroke
· Damage to teeth, lips and gums
· Chest infection
· Awareness (becoming conscious during a general anaesthetic)
Rare or very rare complications
· Serious allergic reactions to drugs
· Damage to nerves
· Damage to eyes
· Vomit getting into your lungs
· Frequently asked questions
Frequently Asked Questions
Q Should I take all my usual medicines or tablets right up to my operation?
Your surgeon and anaesthetist will tell you which drugs they would like you to take and which ones to stop. It helps if you bring all your medication with you so that they will know what you usually take.
Q Do other drugs affect the anaesthetic?
Most drugs that treat heart, circulation or breathing problems have some effect on the anaesthetic. Your anaesthetist will be familiar with all the drugs that you take and will adjust the anaesthetic accordingly.
Q How do you know how much anaesthetic each person needs?
The amount of anaesthetic needed for a spinal or general anaesthetic varies with your age, your weight and build and your general health. There is no easy formula! Anaesthetists use their judgment and experience. They stay with you all the time and they adjust the anaesthetic as needed.
Q Can I bring a relative or friend with me?
It may be possible to arrange this. If this would help you, please ask the nurses on the ward or your anaesthetist if a relative or friend could come into the anaesthetic room.
Q How long does it take to regain consciousness after a general anaesthetic?
You regain consciousness in 5 – 20 minutes. It may be longer before your memory fully returns.
Q Am I likely to get long term backache if I have a spinal injection?
You may have a bruise at the site of the injection, but this soon passes. Backache due to arthritis is common in people having a hip or knee replacement. It is not made worse by having a spinal or epidural injection.
Partners in Care
We want you to be our partner in care. Please try to help by:
· Providing full information on your health history and related matters
· Following the advice given to you
· Accepting responsibility if you refuse treatment or medical advice
· Taking reasonable care of your own property and respecting the property of other people in hospital
· Keeping appointments and giving adequate notice if unable to do so
· Switching off your mobile phone when in hospital
· Not smoking
· Ensuring reasonable and responsible behaviour by yourself and your visitors
· Please return any equipment when you have finished with it
If you have any questions, which are not answered by this booklet, then please don’t hesitate to ask your doctor or one of the nursing staff.