Information about anaesthesia

What is Anaesthesia? retract
  • Anaesthesia is pronounced an-ass-thees-ya. It may best be thought of as freedom from pain and is broadly classified into three types: General, Regional and Local. General Anaesthesia We often think of general anaesthesia as going to sleep for an operation. General Anaesthesia is actually a carefully controlled state of unconsciousness to pain and a loss of awareness of surroundings. It is achieved by a combination of drugs that are injected into the bloodstream and gases that are breathed into the lungs. Regional Anaesthesia This is where we numb part of the body while you remain awake. The most common forms of regional anaesthesia are Epidurals and Spinals but there are many other types that can just numb an arm or a leg for instance. Local Anaesthesia Operations on a very small part of the body, such as a skin lump or an eye operation may be possible just by numbing a localised area. Local anaesthesia may also be combined with sedation to help you remain calm.
What is Sedation? retract
  • Sedation, sometimes called twilight anaesthesia, is commonly used where a procedure would be too uncomfortable to be performed awake, but where it is not desirable, safe or necessary to have a general anaesthetic. Some of the more common procedures performed under sedation include eye operations, colonoscopy, gastroscopy, or minor procedures such as removal of skin lesions or dental extractions. A person under sedation is neither anaesthetised nor asleep. It is quite common for a person to be awake and talking during a procedure and yet have no recollection of anything after the procedure has finished. This is why most people who have had sedation believe that they were asleep throughout. It is not uncommon to have some hazy recollections of feeling movement or hearing voices during sedation. It is important to realise that this does not mean that the sedation has failed. There should not be any painful or uncomfortable experiences during sedation and if you do experience anything unpleasant simply inform the anaesthetist who will give you something extra.
About Your Anaesthetist retract
  • An anaesthetist (an-ees-thet-ist) is a doctor who has undergone additional specialist training. The minimum amount of training to become a specialist is 7 years, in addition to the 6-8 years required to become a doctor. Your anaesthetist is therefore a highly trained specialist and an expert in the field. Your anaesthetist does much more than just put you to sleep. They remain by your side or in close proximity at all times while you are anaesthetized and constantly monitor your level of consciousness and vital signs such as blood pressure and heart rate. Your anaesthetist is trained to recognize and treat any complications or conditions that may arise during anaesthesia.
What Happens During General Anaesthesia? retract
  • Every anaesthetic is different. This is a summary of the most common things that happen but if there are particular issues with your anaesthetic they will be discussed with you beforehand. The anaesthetist will usually see you before your operation wither in the pre-op clinic, in the ward, day-surgery unit or outside the operating theatre. Any questions or concerns that you have can be discussed and the best anaesthetic management plan to suit you and your condition will be discussed. An intravenous cannula (or IV drip) will be put into a vein, usually on your arm or hand. This process usually causes a short sharp pain but can sometimes be associated with bruising. Sometimes it can be difficult to insert the cannula and even very experienced anaesthetists sometimes need several attempt. You will have several monitors attached before going off to sleep. These include monitors that look at your heart-beat, blood pressure, oxygen levels and anaesthetic gases. They are used routinely and are not painful although the blood pressure cuff gives your arm a bit of a squeeze! You will be given oxygen to breathe through a mask. Some people find this a bit alarming but it is important to ensure that you have lots of oxygen before going off to sleep. When the anaesthetist is ready to commence the anaesthetic they will inject some drugs into the IV cannula. These might sting a bit as they run into your vein but they work very quickly and you will find yourself becoming sleepy within about 20 seconds. Depending on the type of surgery the anaesthetist may need to assist or control your breathing while under the anaesthetic. If this is necessary you will have a tube inserted through your mouth or nose into your throat. This tube is put in after you are asleep and usually removed before you are awake so you will not usually be aware that is was there, except that sometimes it can cause a sore throat. During the surgery the anaesthetist closely monitors your level of anaesthesia and vital signs such as heart rate and blood pressure. Many different medications may be administered during the anaesthetic to ensure you are as safe as possible and to make sure you wake up as free from side effects such as pain and nausea as possible. At the conclusion of surgery the anaesthetic is stopped and you will wake up within a few minutes, but will often be drowsy for another half an hour or so afterwards. When the anaesthetist is happy with your condition you will be moved from the theatre to the recovery room where you will be cared for by specially trained nurses. These nurses will give any medications needed to control pain or side effects
What Happens During Regional Anaesthesia? retract
  • You will usually have an IV drip commenced. This allows fluid and medications to be given to prevent or treat any change in blood pressure. You may be given some light sedation at this point if the anaesthetist feels it would be safe and advisable. You will generally have a number of monitors attached to keep an eye on your pulse and blood pressure. These are not painful. The epidural or spinal will be put in either with you sitting up, or lying on your side curled up in a ball. Your back will be washed with antiseptic and a sterile drape will be placed over the area to keep it clean. Some local anaesthetic is injected into the skin of the back. This stings for a moment and is usually the worst part. It is vital that you remain extremely still while the needle is being inserted because it is very important that the needle goes into the correct space. If you feel the need to cough, sneeze or move please advise the anaesthetist before you do so. A spinal begins working within a few seconds, an epidural or nerve block takes several minutes to begin working.
What Happens During Sedation? retract
  • Every procedure is different. This is a summary of the most common things that happen but if there are particular issues with your sedation they will be discussed with you beforehand. The anaesthetist will usually see you before your procedure in the pre-op clinic, in the ward, day surgery unit or outside the operating theatre. Any questions or concerns that you have can be discussed and the best management plan to suit you and your condition will be discussed. An intravenous cannula (or IV drip) will be put into a vein, usually on your arm or hand. This process usually causes a short sharp pain but can sometimes be associated with bruising. Sometimes it can be difficult to insert the cannula and even very experienced anaesthetists sometimes need several attempts. You will have several monitors attached before going off to sleep. These include monitors that look at your heart-beat, blood pressure and oxygen levels. You may be given oxygen to breathe through a mask or nasal prongs. When the anaesthetist is ready to commence the sedation they will inject some drugs into the IV cannula. These might sting a bit as they run into your vein but they work very quickly and you will find yourself becoming pleasantly drowsy within about 20 seconds. During the procedure the anaesthetist closely monitors your level of sedation and vital signs such as heart rate and blood pressure. Many different medications may be administered during the procedure to ensure you are as safe as possible and to make sure you wake up as free from side-effects such as pain and nausea as possible. After the procedure you may still be drowsy for a few minutes and your memory will not be sharp during this time, however your level of alertness will improve quickly. When the anaesthetist is happy with your condition you will be moved from the procedure room to the recovery room where you will be cared for by specially trained nurses. These nurses will give any medications needed to control pain or side-effects.
Before the Procedure retract
  • The anaesthetist must take a full history so the safest type of anaesthetic can be given. Please answer all questions as fully and honestly as possible especially regarding use of medications and other drugs. This information will be kept confidential. Try to cut down on smoking at least a week before surgery and do not smoke at all within 24 hours of surgery if possible. This also applies to alcohol and illicit drugs. It is very important that your stomach is empty before having an anaesthetic because food or drink increases the risks. Make sure you have nothing to eat for at least six hours before the scheduled start time for your surgery. Check with your anaesthetist if not sure. Bring all your normal medicines with you to hospital. Some medications must usually be stopped before surgery, such as diabetic medications and blood-thinning medicines like aspirin, warfarin, iscover or plavix. Most other medicines should be continued, especially heart and blood pressure medicines. You can have a small sip of water to take your tablets. If you have any doubts ask your anaesthetist.
After the Procedure retract
  • You must not drive, operate heavy machinery or sign important documents for 24 hours after the anaesthetic. If your procedure is to be done as a day-stay patient, you must have a responsible person to drive you home and stay with you for the first 24 hours. Catching a taxi home to an empty house is not acceptable.
Is Anaesthesia Dangerous? retract
  • Anaesthesia is not dangerous but everything in life has risks and it is important that you are aware of possible risks before proceeding. Anaesthesia has some minor risks that occur relatively commonly and some serious risks that occur very rarely. The vast majority of people have anaesthesia with no problems and this information is designed to inform you, not to frighten you. Minor complications can include headache, nausea, vomiting, light-headedness, backache, muscle aches and pains, stiffness, damage to teeth, sore throat and bruising. If these complications do occur they are only short-lasting in most people. Serious complications can include allergic reactions to drugs, nerve damage, paralysis, psychological problems or damage to vital organs including heart, brain, lungs, kidney or liver. The risk of dying due to anaesthetic complications is somewhere around 1:40,000 anaesthetics, or about the same risk as flying in a commercial aircraft. Some patients are more at risk than others and your anaesthetist will ask you questions that will help them determine the safest type of anaesthesia for you.
I am worried about post operative nausea and vomiting retract
  • Post operative nausea and vomiting is a complex and multi factorial problem. During an operation your anaesthetist will administer strong pain medication to keep the pain away. These are the most common cause of nausea and vomiting. Depending on the operation the anaesthetist will vary the type and dose of pain medication so your recovery is as pain free as possible. This explains the low incidence of vomiting after a colonoscopy ( non painful no pain medication needed ) compared with shoulder surgery ( strong pain medication needed ).
    There are also other factors; people often vomit after many intra oral surgeries, this is because blood is an irritant to the stomach so the body expels this.
    These days modern anaesthetics wear off after a few hours, so if you continue vomiting after this it is most likely it is the pain medication. Morphine, Pethidine, Endone, Tramadol, and Codeine are all common causes of vomiting. Also there is a very small subsection of people who suffer from travel or motion sickness, awaking from an anaesthetic will often provoke this.
  • All anaesthetists are very aware of the problems of post operative nausea and vomiting and try their best to avoid this. Most of us routinely administer combinations of anti nausea drugs to try to prevent this. We also routinely write anti nausea drugs on the post operative orders, so if you are feeling any nausea ask the nurse for something.
  • What can I do?
    Discuss your fears with your anaesthetist, inform him of any history of motion sickness, take note of any pain medications that make you nauseous. These days modern anaesthetics are a lot better than the past, and we have many new anti nausea drugs. We often see patients that in the past have vomited after every anaesthetic, but now are pleasantly surprised when they wake nausea free. We will always try our best but cannot guarantee.
How much will the anaesthetic cost? retract
  • It is not always possible to give you an exact figure before the operation because fees are calculated according to a number of factors such as the type of operation, type of anaesthesia, your age and health, and how long the operation actually takes. However it is usually possible to give an estimate of costs. These are detailed in a separate sheet or you can request an estimate.
    Estimates
    Note that the amount you get back varies enormously depending on your health fund. The gap can vary between different health funds by several hundred dollars. If you have any questions or concerns, ask your anaesthetist.
Epidural Pain-Relief for Labour retract
  • What is an Epidural?
    Nerves from the spinal cord pass through the epidural space as they go to all parts of the body. Local anaesthetic in the epidural space blocks these nerves so they are unable to carry pain sensations for a period of time. An epidural is the most effective form of pain relief available for labour without causing drowsiness. About 95% of women are very satisfied with the pain relief provided.

  • Are there any side-effects?
    Epidurals are not dangerous. The vast majority of women have epidurals with no problems however all things in life have risks and this information is intended to inform you, not frighten you. The most common problems with epidurals are relatively minor and temporary. They include headache, nausea, shivering and itch. Back pain is common after delivery and other than mild local tenderness at the injection site we do not believe that epidurals increase the risk of back pain. Epidurals can cause your blood pressure to drop and this can make you feel dizzy, light-headed or sick. Headaches can occur after about 1 in 300 epidurals. They usually get better by themselves but sometimes they can be quite severe and need further treatment. Occasionally the epidural solution can be injected into the wrong space. In rare cases this could cause difficulty breathing, convulsions or heart problems. Serious complications such as infection, meningitis, nerve damage, paralysis, drug allergies or even death can occur but are very very rare. It is estimated that the risk of serious permanent nerve damage causing weakness, numbness or paralysis, or causing bladder and bowel problems is around 1 in 150,000 epidurals.

  • Are epidurals painful?
    Epidurals are not usually painful. There is a sting in the back with some local anaesthetic then a bit of pushing and it usually is all over in a couple of minutes. Sometimes it can be difficult to put the needle in exactly the right place and it may take a bit longer and hurt a bit more. The relief of pain from labour is usually worth the brief discomfort of an epidural.

  • What are the effects on the baby?
    The local anaesthetics used for epidurals do not generally have any effect on the baby. The baby is less likely to have breathing problems after delivery if an epidural is used compared to narcotics such as pethidine. If the epidural causes your blood pressure to drop excessively this can cause the baby to become distressed and this needs to be treated with extra fluids or medication. Good pain relief can reduce the level of stress hormones in the mother. Many Studies have shown that in the short-term babies do better when epidurals are used.

  • Can I still have a normal delivery?
    Some old studies suggested that epidurals increase the risk of needing forceps or caesarean delivery but most newer studies have shown that there is no difference. New anaesthetics let you feel the tightening of a contraction without feeling the pain and you will still be able to “push” when the time comes. There is no reason why you should not be able to deliver normally.

  • Are there any alternatives?
    Everybody feels pain differently and some women do not need epidurals. Other methods of pain relief are available but none are as effective or leave you as alert as an epidural. Narcotics such as pethidine may help the pain but can have side effects such as drowsiness and nausea. Laughing gas (nitrous oxide) may help relieve pain in some people but is not effective for everyone and can make you feel delirious. Other options include breathing exercises, hypnosis, relaxation techniques or even acupuncture. You should discuss all the options with your midwife, obstetrician or anaesthetist. Consider all the options before labour but be prepared to change your mind if your original choice is not working for you.

  • Can everyone have an epidural?
    Not everyone can have an epidural. Some medications such as drugs that thin the blood increase the risk of complications. Some people with back problems or who have had back medical conditions or infections make epidurals inadvisable. Sometimes labour will progress so fast that there is no time for an epidural. If you don’t request an epidural until labour is well advanced there may not be enough time to perform the epidural before delivery. This is a common occurrence so if you are contemplating asking for an epidural, do not leave it too late.

  • What is going to happen to me?
    You will usually have an IV drip commenced if it has not already been done. This allows fluid and medications to be given to prevent or treat any change in blood pressure. The epidural will be put in either with you sitting up, or lying on your side curled up in a ball. Your back will be washed with antiseptic and a sterile drape will be placed over the area to keep it clean. Some local anaesthetic is injected into the skin of the back. This stings for a moment and is usually the worst part. The epidural needle is carefully inserted and then a catheter is fed through the needle into the epidural space. It is vital that you remain extremely still while the needle is being inserted because it is very important that the needle goes into the correct space. If you feel a contraction coming on just let the anaesthetist know and they can stop until the contraction passes. It will take 15-20 minutes for the epidural to take effect so you will still feel a couple of painful contractions until the epidural is working. During this time your blood pressure will be checked frequently. Let your midwife or doctor know if you feel dizzy, light-headed or sick. As the epidural starts to take effect you may get a feeling of warmth, heaviness, numbness or pinsand- needles spreading up from your legs into your tummy. You should not normally experience any drowsiness or confusion. You will usually have a catheter put into your bladder to keep it empty. After delivery, the epidural catheter is removed quite easily and with little if any discomfort. The epidural will wear off after a couple of hours.

  • What if I need forceps or caesarean?
    If your epidural has been working well and providing good pain relief, it is usually possible to top-up the epidural with a stronger solution so that you can be awake for the birth of your baby by caesarean section or forceps. Occasionally your anaesthetist will recommend either a spinal anaesthetic (which is a bit like an epidural) or a general anaesthetic. If you have a Caesarean Section under a spinal or epidural anaesthesia the procedure will not be painful but you will feel some movement and pressure sensations. Let your anaesthetist know if you experience any discomfort, nausea, faintness or lightheadedness.
Anaesthesia for Caesarean Section retract
  • Regional or General Anaesthesia
  • The vast majority of Caesarean Sections in the Western world are performed under a regional anaesthetic, either a spinal or an epidural or a combination of the two, however it is sometimes necessary or advisable to have a general anaesthetic, for example where there is no time to establish a regional anaesthetic or where there is a particular reason that regional anaesthesia is not possible or not advisable. For more information see our section on General Anaesthesia. Regional anaesthesia is generally preferred because:


  • Pregnancy causes a number of changes in the mother’s body to help with development of the baby and to prepare for delivery. While completely normal, some of these physiological changes do make general anaesthesia more risky than in an equivalent non-pregnant patient.

  • Drugs used for general anaesthesia cross the placenta so the baby also receives a general anaesthetic and will have some extra hurdles immediately after delivery.
  • Studies have shown that in the short term, babies do better if delivered under a regional anaesthetic.
  • Being awake for the delivery also allows mother and baby to bond immediately after delivery without having to wait for recovery from a general anaesthetic.
  • Less post-operative pain and other side effects.


    While ultimately it is every woman’s choice whether they have a regional or general anaesthetic for Caesarean Section, most anaesthetists would strongly recommend regional anaesthesia as being safer for both mother and baby. If you have questions or concerns, you are welcome to contact our rooms so you can have a consultation with one of our specialist anaesthetists in advance of delivery. Spinal and Epidural anaesthesia are very similar techniques but there are a couple of important differences. Both involve a needle inserted in the back and the use of local anaesthetic that blocks transmission of nerve impulses in the spinal cord. Both result in a loss of pain sensation from the lower half of the body so that you are temporarily numb and weak from the breasts down. Both mean that you can be wide awake for the delivery of the baby yet feel no pain. Neither technique involves the spinal cord itself.
    An epidural deposits the anaesthetic just outside the fibrous sac that covers the spinal cord and fluid. A spinal deposits the anaesthetic inside this sac. In simple terms an epidural is slow onset, long duration while a spinal is fast onset, short duration Typically an epidural is used when the block may need to last a long time because a thin plastic catheter can be left in the epidural space and further doses (top ups) can be given later if necessary. Generally, though not always, a spinal is a single shot technique with a single injection and no catheter left behind. As a general rule a spinal will easily last long enough to perform a Caesarean Section.
    An elective Caesarean Section is usually done with a spinal anaesthetic while an epidural is used if the patient requires pain relief in labour. If the patient subsequently has to have an emergency Caesarean the epidural can be easily topped up for this purpose. Sometimes a spinal can be combined with an epidural to give the advantages of fast onset and long duration.


    Risks of Anaesthesia for Caesarean Section
    Anaesthesia for Caesarean Section is not dangerous but everything in life has risks and this is no different. It is important that you are aware of possible risks before proceeding but remember that serious complications are incredibly rare. The vast majority of people have anaesthesia with no problems and this information is designed to inform you, not to frighten you. It is fair to say that the very process of childbirth carries more risk than the anaesthesia.

  • Minor complications can include headache, nausea, vomiting, light-headedness, backache, muscle aches and pains, stiffness, damage to teeth, sore throat and bruising. If these complications do occur they are only short-lasting in most people.
  • Nausea and vomiting is less common with regional anaesthesia than with general anaesthesia. There are many hormonal changes that can cause nausea, and if you start eating and drinking too soon after a Caesarean Section this can cause vomiting. A regional anaesthetic can cause nausea if your blood pressure drops too low so we keep a fairly close eye on this.
  • Headaches due to leakage of the fluid occur about once in every 100 procedures. The headaches usually only last a few days and go away by themselves. However on occasion the headache can be so severe or long lasting that a second epidural procedure may be needed.
  • Back pain is a common problem after pregnancy and is no more likely if you have a regional anaesthetic for Caesarean Section than if you have a normal delivery.
  • Serious complications can include allergic reactions to drugs, nerve damage or damage to vital organs including heart, brain, lungs, kidney or liver. The risk of dying due to anaesthetic complications is somewhere around 1:40,000 procedures, or about the same degree of risk as flying in a commercial aircraft. The risk of serious permanent nerve damage (such as paralysis or having bowel or bladder problems) is probably less than 1:150,000 procedures.

    The majority of mothers can have a regional anaesthetic. Sometimes the procedure can be particularly difficult, for example in patients who are overweight or who have had back problems or back surgery, however even in these patients it is often still possible to do a regional anaesthetic. Occasionally there may not be enough time to perform a regional anaesthetic or there may be some other reason that makes a general anaesthetic more appropriate.

    What Happens During the Epidural or Spinal?
    The anaesthetist will usually see you before your procedure in the pre-op clinic, in the ward or outside the operating theatre. Any questions or concerns that you have can be discussed and the best management plan for you will be formulated. An intravenous cannula (or “IV drip”) will be put into a vein, usually on your arm or hand. This process usually causes a short sharp pain but can sometimes be associated with bruising. Sometimes it can be difficult to insert the cannula and even very experienced anaesthetists sometimes need several attempts. You will have several monitors attached to look at your heart-beat, blood pressure and oxygen levels. You may be given oxygen to breathe through a mask or nasal prongs but this is not universal. The epidural or spinal may be inserted with you sitting up or lying on your side curled up into a ball. It is important that you arch your back outwards towards the anaesthetist, remain as still as possible and obey all instructions. Your back will be cleansed with anti-septic solution and a sterile drape applied. There is a short sting with local anaesthetic in the back then a bit of pushing and prodding for a minute or two and that is about it. Most people are pleasantly surprised that the needle in the back is nowhere near as bad as they had feared.


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