ANAESTHETIC INFORMATION

It is important to read this information carefully before seeing your anaesthetist. The purpose of this website is to help you to understand your anaesthetic and to assist you in making informed decisions about your care. It contains a lot of information and you may need to read it more than once. Unfortunately, this amount of information is necessary to have you well informed. If you would like to, it is a good idea to discuss this information with a member of your family or a friend. The information provided is of a general nature and does not take your individual circumstances into account. It cannot replace specific advice given to you by your own anaesthetist. If you have any questions or concerns, or there is anything don't understand, talk to your anaesthetist.

In Australia, most anaesthetics are provided by specialist anaesthetists or trainee anaesthetists under the supervision of specialist anaesthetists. However, this is not always the case. You should feel welcome to ask about the qualifications of the person anaesthetising you.

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WHAT IS AN ANAESTHETIC?

The purpose of an anaesthetic is to remove the pain or awareness of an operation or procedure. There are a number of ways in which your anaesthetist can do this. Your anaesthetist will provide the type of anaesthetic most suited to your needs. This decision is based on a balance between your state of health, the specific risks and benefits for you, the type and length of procedure and your preference.

In addition to removing the pain or awareness of an operation, your anaesthetist looks after your general well being during and after your procedure. This may include giving intravenous fluids and, when required, blood transfusions to replace bloodloss caused by the surgery or the use of drugs to maintain optimal levels for blood pressure, heart rate and rhythm and breathing. Your anaesthetist also manages your postoperative pain relief.

A general anaesthetic is given using a combination of drugs that are injected into you and gases that you breathe. It is used to make you unconscious in a carefully controlled way. Your body has a number of reflex responses to the painful stimulus caused by the surgery, even when you are not aware of the pain. These responses include raising your blood pressure, raising or lowering your heart rate and changes to breathing. As well as making you unconscious, the anaesthetist also controls the changes in your blood pressure, heart rate and breathing that are caused by the surgery. For some operations, drugs are used to weaken your muscles and a machine called a ventilator is used to do your breathing for you. Muscle relaxing drugs are used in long procedures or to make it possible for the surgeon to do a particular operation. For other procedures, you are asleep and able to breathe by yourself and do not need a machine to assist you.

Sedation is the use of drugs to make you sleepy, but not as deeply asleep as a general anaesthetic. The anaesthetist injects these drugs into a vein intermittently throughout the procedure to control the depth of sleep. Sedation can be used for a large number of investigations and procedures, such as gastroscopies and colonoscopies. Often, sedation is used in combination with local anaesthetic injections, which make parts of the body go numb. Sedation is usually used for shorter, less painful procedures, but can be used for some types of larger operation. It has advantages over a general anaesthetic in that it may be safer, causes less nausea or vomiting, and allows quicker recovery. It is not unusual for patients receiving sedation to wake up during the procedure and to be aware of what is going on around them.. After the procedure, most patients do not remember being awake, but some patients do recall what has happened. This is not an unpleasant experience and should not be of concern.. If you have any concerns about this, you should talk to your anaesthetist.

Local anaesthetic blocks involve the injection of special drugs that make specific parts of the body go numb. This can range from making a single finger go numb to making half of your body numb. These blocks are particularly safe when small parts of the body are made numb. Larger blocks, such as epidural or spinal anaesthetic, can also be safer than a general anaesthetic. Local anaesthetic blocks provide better pain relief following surgery and are often combined with sedation. They can also be used with general anaesthetic.

TYPES OF LOCAL ANAESTHETIC BLOCK

Local anaesthetics may be injected directly at the site of surgery, or to block a single nerve or even whole groups of nerves to make parts of the body go numb and prevent pain.

Intravenous limb block. For this type of block, your anaesthetist puts a tourniquet around your upper arm or leg and injects a local anaesthetic drug into a vein in your hand or foot. This is a very reliable block for making the arm numb, particularly for short procedures and is less commonly used in the leg. However, there can be some discomfort from the tourniquet and for this reason it is common for the anaesthetist to give sedation as well.

Nerve plexus blocks. Nerves are grouped together in some parts of the body. Such a group of nerves is called a plexus. The whole upper limb and parts of the lower limb can be made numb by injecting a local anaesthetic drug near the groups of nerves that supply the limbs. For the upper limb, this is most commonly done by injecting the local anaesthetic into the armpit, but can also be done by injecting in the neck, or either above or below the collarbone. For the lower limb, this can be done in the upper thigh or behind the knee. It is common to give sedation when the block is put in. This technique is best used for longer, larger operations on the limbs.

Individual nerve blocks. Individual nerves in the face, mouth and limbs can be blocked by injecting the local anaesthetic near the individual nerve which supplies the area of the body where the procedure will take place. These blocks are particularly safe. Because smaller doses of local anaesthetic are required there are less potential complications. This type of block is most useful for surgery on the hand or fingers.

Spinal and epidural anaesthetics. An epidural or spinal anaesthetic is an injection of local anaesthetic, often with other pain-relieving drugs, into the lower back. Your anaesthetist uses this type of block to make a large region of your body go numb. Your anaesthetist may recommend this type of block, because it may provide better safety, quicker recovery and better postoperative pain relief than a general anaesthetic. Running down the middle of the backbones (spine) there is a sac of fluid called the dural sac. A spinal anaesthetic is an injection of local anaesthetic through the back, into the fluid inside the dural sac. An epidural anaesthetic is an injection of local anaesthetic through the back, into the area outside of the dural sac. Nerves travel both inside and outside the dural sac and the local anaesthetic is used to block these nerves and make parts of the body go numb.

Epidural anaesthetics are usually used for treating pain postoperatively or in labour. Epidurals can also be used to treat long term pain. This is because a plastic tube, called an epidural catheter, can be threaded into the epidural space and left there for ongoing doses of local anaesthetic until pain relief is no longer required. An epidural may be used for several days. Spinal anaesthetics are usually used as a single injection of local anaesthetic for an operation. The single injection lasts for 2-3 hours Spinal anaesthetics are more commonly chosen for caesarean section, because they block the nerves more completely and more rapidly than an epidural.

Sometimes a combined epidural/spinal technique is used and can offer the benefits of both techniques

Another common local anaesthetic block is a caudal anaesthetic. This is like an epidural anaesthetic, but given lower down in the back.

WHAT SHOULD YOU DO BEFORE YOUR ANAESTHETIC?

•  You will need to follow the instructions your surgeon gives you.

•  You will need to fast before your anaesthetic . This means no food or drink, not even water, lollies or chewing gum. You need to fast for at least four hours and for some operations even longer. Your surgeon will let you know how long you need to fast for. If you don't fast, there is a risk you will vomit while under the anaesthetic and that this material will go into your lungs and cause serious lung infections.

•  Keep taking your regular, prescribed medications, but remember to let your surgeon or anaesthetist know what you are taking. It is especially important to take medication to control your blood pressure, asthma or angina on the day of the anaesthetic. It is okay to take a sip of water with your medicines. If you are diabetic you will need to adjust your medications because of the surgery and must ask your surgeon or anaesthetist what to do before the day of your operation or procedure. Not eating and surgery change your body's insulin needs.

•  If you are taking blood-thinning drugs (anticoagulants) such as aspirin , warfarin , plavix , iscover, fragmin or clexane , you need to talk to your surgeon or anaesthetist about whether you need to alter these medications before the day of the operation. These may need to be altered weeks before you can have the operation.

•  Do not take herbal and alternative products for at least two weeks before your anaesthetic, as some of these products may interfere with the anaesthetic, blood clotting and blood pressure. If you are unsure, talk to your doctor.

•  Tell your anaesthetist if you are pregnant or may be pregnant.

•  It is best to stop smoking for as long as you can before your anaesthetic.Stopping smoking is always better for your health and stopping for at least 24 hours before surgery improves your blood's ability to carry oxygen.

•  If you object to blood transfusions you should let your surgeon know. If you are having an operation where blood loss is likely, it is sometimes possible to donate your own blood prior to your operation, but this needs to be done well in advance. You should talk to your surgeon about this. Donated blood is carefully screened, but the risks of infection or reactions cannot be totally eliminated. Your   doctor will only consider giving you a blood transfusion if the benefits to you outweigh the risks.

•  Your anaesthetist will usually see you on the day of your operation, if you have any concerns or questions you would like to discuss before this, you should contact your anaesthetist prior to the day of the procedure.

•  If you have any serious health problems, let your anaesthetist know before the operation. Your anaesthetist is especially interested in lung or heart problems; problems with blood clotting; or if you or anyone in your family has had problems with anaesthetics in the past. You will receive better care, if your anaesthetist has all the information.

WHEN YOU SEE YOUR ANAESTHETIST

·            When you see your anaesthetist on the day of your operation, you will be asked a number of questions about your general health, medical history, family medical history, dental history, anaesthetic history, especially any problems with past anaesthetics, medications and allergies. Your anaesthetist needs to know about any problems with your health . You will also be asked about the procedure or operation you are about to have and how long since you last ate or drank. Bring all the medications you are taking with you to show your anaesthetist. It is helpful if you bring a list of the medications and doses you take as well.

·            You will need to tell your anaesthetist about all the drugs you take, including recreational drugs and alcohol, as these too may interfere with the anaesthetic or alter how much anaesthetic you need.

·            Your anaesthetist will also collect personal details such as your name, date of birth, address, health fund and Medicare details and motor vehicle or worker's compensation information, if required.

The personal information collected by your anaesthetist is used for the purposes of providing you with anaesthetic care, referral and discussion with other health care providers looking after you, billing and medical indemnity purposes. Government Privacy Legislation protects all the information collected

·            Your anaesthetist will also perform a physical examination, concentrating on your heart and lungs.

·            Your anaesthetist will discuss the anaesthetic with you, including the associated risks; the usual side effects you may experience and planned pain relief after the procedure. You will have the opportunity to ask questions and are encouraged to do so.

·            Your anaesthetist may order a medication to relax or calm you before the procedure or operation. Usually this is not necessary, especially when you are having day surgery, as this type of medication may keep you drowsy for longer and may delay your going home. For children, local anaesthetic cream may be used to reduce discomfort at injection sites.

DURING YOUR ANAESTHETIC

The anaesthetic may be started by giving you an injection of special anaesthetic drugs into a vein or by giving you special gases to breathe through a facemask. Oxygen may be given through a facemask before the anaesthetic starts. Your anaesthetist routinely uses an intravenous line (drip), a pulse oximeter, blood pressure monitor and an ECG during your anaesthetic.

Intravenous Line. An intravenous line or drip is a small plastic tube or cannula that is inserted into a vein. A vein is a blood vessel that carries blood back to the heart. Your anaesthetist uses the drip to give you drugs or fluids during and after your anaesthetic. Risks associated with an intravenous drip include pain and bruising at the insertion site that usually resolves in a few days and infection.

Pulse Oximeter. A pulse oximeter is a small peg that your anaesthetist places on your finger, toe or earlobe to monitor your pulse and the oxygen level in your blood.

Blood Pressure Monitor. Your blood pressure is monitored via a cuff placed around your upper arm. The cuff can be inflated either manually or automatically in order to measure your blood pressure .

ECG. An ECG, or electrocardiograph, monitors the electrical activity of your heart. It is not invasive and small electrodes or leads are connected to sticky patches that are placed on your chest and limbs. Your anaesthetist uses the ECG to monitor the rate and rhythm of your heart. An ECG also provides information about whether enough oxygen is getting to the heart, past damage to the heart and how well your heart is functioning. The only side effect of an ECG may be some skin irritation from the sticky patches.

Your anaesthetist understands the importance of looking after your wellbeing very carefully during your procedure and remains with you during your whole anaesthetic. In Australia an aneasthetist only cares for one patient at a time. Your anaesthetist uses sophistocated equipment to monitor you during your anaesthetic. This equipment is used to measure your breathing, oxygen level, blood pressure, heart rate, heart rhythm and the level of anaesthetic. Your anaesthetist adjusts your anaesthetic according to your needs.

For large operations or for sicker patients, your anaesthetist may use some of the following procedures to monitor you more closely and provide you with optimal care. These procedures are not used routinely for most operations.

Arterial Line. Arteries are blood vessels that carry blood away from the heart. An arterial line is a plastic tube or cannula that is inserted into an artery, usually at the wrist. Your anaesthetist uses an arterial line to measure blood pressure very accurately or to collect blood samples. Arterial lines are used with some anaesthetics or in Intensive Care Units. Risks associated with arterial lines include pain and bruising that can be more severe than that caused by an intravenous line, but which still resolves within a few days, or infection. There is an extremely small risk that the artery will become blocked and cut off the blood supply to part of the hand. This would not normally cause a problem as two arteries carry blood to the hand in most people. However, in a small number of people only one artery supplies the hand and this type of blockage may cause permanent damage to the hand.

Central Line. A central line is a plastic tube inserted into a major vein in the neck, or below the collarbone. This is a larger tube than an intravenous drip and your anaesthetist uses this for measuring pressures in the veins, giving fluids and drugs and assessing how much fluid is in your body. A central line is more likely to be used in association with larger operations or to closely monitor more seriously ill patients and does not need to be changed as often as intravenous drips do. Risks associated with Central Lines include pain; bruising and infection as with other lines into blood vessels, however because of the position of a central line there are also some other potential risks. It is possible to damage nearby structures when a central line is being inserted, these structures include the lung or the carotid artery (the main artery in the neck) or the subclavian artery (main artery to the upper limb).

Nasogastric tube. A nasogastric tube is a plastic tube that goes from your nose down into your stomach to help empty the contents from your stomach. Even when you haven't been eating your stomach still makes acid and your surgeon may ask your anaesthetist to insert a nasogastric tube, especially if you are having surgery on your intestines. There is a very small risk of damage to the nose, throat or oesophagus when the tube is inserted.

All needles, syringes, drugs for injection, intravenous equipment and fluids are sterile items that are used for one patient only. Other items of anaesthetic equipment are either single patient use, are sterilized before each use in accordance with Australian Standards, or are protected by viral and bacterial filters. These measures have been shown to be extremely effective in preventing cross-infection.

AFTER YOUR ANAESTHETIC

When the operation or procedure is finished, you will be taken to the Post Anaesthetic Care Unit. Your anaesthetist hands your care over to specially trained recovery nurses in the Post Anaesthetic Care Unit. You will remain in this specialized area for at least half an hour while you recover from your anaesthetic. It is standard to be given oxygen to breathe and for monitoring of the blood pressure, heart rate, breathing and oxygen level to continue at this time. The effectiveness of pain relief is also assessed.

POSTOPERATIVE PAIN

Your anaesthetist aims to have you as comfortable as possible following your operation or procedure and will order pain relief for you. However, it is not always possible to have you totally free of any discomfort. The use of local anaesthetic blocks, with or without general anaesthetic best reduces post operative pain, but other methods include: tablets, mixtures, suppositories (medicine via the back passage), injections into muscles or veins or combinations of these.

A common method for delivering postoperative pain relief is to use an electronic pump to deliver doses of pain reliving medicines through the intravenous drip. The pain relief can be given to you at a steady rate from the pump, or be available as small doses when you push a button attached to the pump, or both.

Your pain relief requirements will depend on the type of procedure you are having. While you are in the Post Anaesthetic Care Unit, the recovery nurses will ask you whether you have any pain. As different people need different amounts of pain relief, it is important to tell the nurses how you are feeling. If you have any concerns about postoperative pain, you should discuss them with your anaesthetist.

SIDE EFFECTS

Side effects are minor, unpleasant reactions to an anaesthetic. These occur commonly and are usually of short duration.

Dizziness, drowsiness, headache and blurred vision are common and usually wear off quickly. Occasionally muscle weakness can be noticed immediately after the anaesthetic, and may briefly cause difficulty with breathing. Occasionally patients wake up feeling agitated or teary. These problems recover quickly.

Swelling and bruising at injection sites are common and recover within a few days.

Short-term memory loss is common. Most patients do not remember being awake in the Post Anaesthetic Care Unit. Short-term memory loss usually recovers by the next day, but may last longer in patients who undergo larger operations, require stronger pain relieving drugs or who are elderly.

Nausea and vomiting are the most common side effects of general anaesthetics, up to 30% of patients experience some nausea or vomiting. They are more likely to occur with longer and larger operations, abdominal surgery- including laparoscopy, and surgery on the ear. They are less likely to occur when sedation or local anaesthetic techniques are used. There is a lot of individual variation, with some patients more likely to experience these side effects. If you have had problems with nausea and vomiting after anaesthetics in the past, tell your anaesthetist, as there are ways to tackle this problem.

It is common for your anaesthetist to place a tube in your airway to help maintain your breathing while you are anaesthetized. This may cause a sore throat or hoarse voice, which usually recovers within 24 hours.

After surgery on the mouth or face, it is possible to have black eyes or a nosebleed.

Muscle aches and pains are uncommon, but can occur when certain anaesthetic drugs are used. These are more likely to occur after emergency surgery, but usually recover within three days. These aches and pains are usually controlled with paracetamol.

RISKS AND COMPLICATIONS

Anaesthetics in Australia are among the safest in the world. For a fit and healthy person, general anaesthetic and local anaesthetic blocks are no more hazardous than a couple of short trips in the car. This level of safety is because, in addition to being a fully trained medical practitioner, your anaesthetist has spent an additional five years completing a high level of specialist training in anaesthetics, pain relief and treating emergencies and participates in continuous education and professional development. The newer anaesthetic drugs and modern anaesthetic equipment make having an anaesthetic the safest it has ever been.

However, as with driving a car, it is not possible to totally eliminate risk. Although very uncommon, anaesthetic complications do occur and these complications may be serious. These risks may be higher for people who are less healthy, especially for those with heart or lung disease and those undergoing longer, more complex procedures.

Awareness. During a general anaesthetic, it is possible to be awake, unable to move and aware of what is happening around you, This may include feeling the operation. This is called awareness and only occurs during general anaesthetics where muscle-relaxing drugs are used. Most general anaesthetics do not require muscle-relaxing drugs. It is also possible to dream of being aware, without it actually happening. Where muscle-relaxing drugs are used, awareness may occur in up to 1% of patients. For patients who are given sedation rather than a general anaesthetic, being aware and comfortable is expected and is not of concern.

Death or serious complication. This may include conditions such as: heart attack; stroke; brain damage; blindness; fitting; pneumonia; DVT (blood clot in the leg) and pulmonary embolus (blood clot in the lungs); major allergic reaction; irregular heart beat; kidney, lung or liver failure; permanent nerve damage; permanent damage to voice; eye damage; and infections or reactions to blood transfusions. Even though many patients are worried about this, the chance of dying or having a serious complication because of an anaesthetic is extremely low. For a young healthy person, the chance is so low that it is not possible to measure it accurately. For those with poor general health, especially heart or lung disease, the risks may be greater. You should discuss your individual risks with your anaesthetist.

Damage to teeth. Every care is taken by your anaesthetist not to damage teeth (including false teeth, capped teeth and bridges). Although dental damage is uncommon, it is important to understand that with any general anaesthetic there is a small risk that teeth may be damaged. Although very uncommon, injury may also occur to the larynx (voice box), vocal chords, lips, throat or tongue.

Incidental injury. Very rarely, a patient who is unconscious or drowsy is injured accidentally. For example, falls from the operating table, eye damage, pressure injury, stretching injury, back injury associated with being moved, or unintentional burns. Nerve damage may occur despite the best positioning or padding of pressure points, resulting in an area or region of numbness, pain or weakness.

RISKS ASSOCIATED WITH LOCAL ANAESTHETIC BLOCKS.

There are many situations in which a local anaesthetic block with or without sedation is safer than a general anaesthetic and you should discuss this with your anaesthetist. Local anaesthetic blocks also provide better postoperative pain relief and may lead to quicker recovery.

As with general anaesthetics, there are risks associated with local anaesthetic blocks.

Pain at injection site. Pain and bruising at injection sites are common but are expected to resolve within 2 weeks

Inadequate block. With some types of local anaesthetic block it is common to feel pressure and pulling during the operation. You should not feel pain. However, local anaesthetic blocks are often temperamental. They can be patchy, may only block one side, may block too high or too low, or may miss blocking individual nerves and as epidural catheters are only held in by tape, they can leak or fall out. In some cases, local anaesthetic blocks can be inadequate. There are several ways of managing these problems. Changes in your position and additional doses of local anaesthetic or increased sedation often fix these problems, however, in some cases, it may be necessary to re-insert the local anaesthetic block or proceed to a general anaesthetic.

There is a lot of individual variation in people's size and shape and requirements for local anaesthetic. It is not always possible for the anaesthetist to put in some blocks such as an epidural or spinal injection. This can result in the need to have a general anaesthetic

Death or serious complications. These are the same types of risks as those discussed for general anaesthesia. Although these risks are often lower with a local anaesthetic block than with general anaesthesia, they still exist and cannot be totally eliminated.

Post spinal headache. A headache can occur after spinal or epidural injection in up to 1% of healthy young people and is far less common in older age groups. This headache can be mild or severe and usually resolves spontaneously over 1-3 weeks. It can be cured more quickly using an epidural injection of the patient's own blood. If you have a persistent headache following an epidural or spinal anaesthetic you should contact your anaesthetist. It is also important to understand that there are many other causes of headache that are more common. It is also possible to have temporary deafness following a spinal anaesthetic.

Difficulty passing urine. A spinal or epidural anaesthetic may make it difficult to sense a full bladder. Occasionally a catheter is needed to drain the urine. There is a small risk of bladder infection associated with using a urinary catheter.

Infection. Infections are extremely rare, so rare that it is not possible to give an accurate incidence. All of the needles, catheters, local anaesthetics, intravenous drips, syringes, tubing and fluids are sterile and used for one patient only. Your anaesthetist uses a sterile technique to insert a local anaesthetic block. However, it is not possible to totally eliminate the risk of infection at the injection site. With epidurals and spinal anaesthetics it is possible to develop an infection around the spinal cord, causing meningitis or an abscess. This extremely rare type of infection may have serious consequences and result in brain damage, paraplegia or death. Infection may require antibiotic treatment, or very rarely surgery.

Nerve Damage. Nerve damage is uncommon and usually only temporary, but rarely may be permanent. The type and extent of damage depends on where the block is placed. Nerve damage may range from causing a very small area of numbness, pain or weakness to, in extremely rare cases, paraplegia or quadriplegia. Once again, these risks are usually lower than those of a general anaesthetic.

WHEN YOU GO HOME

• Anaesthetic drugs can remain in your system and impair your judgment for 24 hours after an anaesthetic.
• Don't drive a car, operate dangerous equipment or tools, make important decisions, sign legal documents or drink alcohol for at least 24 hours after the anaesthetic.Arrange for a responsible adult to accompany you home by car or taxi (don't take public transport) and stay with you for 24 hours.
• Rest quietly at home and arrange for someone else to care for small children or other dependants.
• Local anaesthetics take time to wear off completely. If part of your body is still numb, you need to take care not to injure yourself.
• Make sure you have a clear understanding of which medications to take, especially for pain relief. You may need extra pain relief when a local anaesthetic block wears off.
• If you have any concerns call your anaesthetist, surgeon or the facility at which you were treated.

OUT OF POCKET COSTS

If you are treated as a private patient, there will be an out of pocket cost with most anaesthetic services. There are no standard charges, each anaesthetist sets his or her own fees. The level of the ‘gap' or out of pocket cost will also depend on whether or not you have Private Health Insurance, the type of insurance you have, the type of procedure you are undergoing and how long the procedure takes. You should ask your surgeon or anaesthetist about the cost of your anaesthetic.

This information has been prepared by Dr G. Eastaugh MMBS, FANZCA and Dr L Eastaugh MBBS, MBA to give you a better understanding of your anaesthetic, but cannot replace professional advice regarding your individual circumstances. It is important that you are satisfied that you understand the information regarding both your procedure and the anaesthetic. If you are unsure or concerned about any of this information you should talk to your anaesthetist. Your anaesthetist can assess you and discuss your risks at the pre anaesthetic visit or earlier if required.

Copyright. © Tellwave Pty Ltd 2003 (Revised July 2007). All Rights Reserved.

Except as expressly stated otherwise, you are authorized to view, copy, print and distribute the content of the preop.com.au Web site subject to the following conditions: (i) it is used for informational, non-commercial purposes only; (ii) any copy or portion must include the Tellwave Pty Ltd copyright notice above and acknowledge authorship; (iii) no modifications are made; and (iv) Tellwave Pty Ltd reserves the right to revoke such authorization at any time, and any such use shall be discontinued upon written notice from Tellwave Pty Ltd.

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