What kind of anaesthesia will I have? 

The choice of anesthesia depends on many factors, including the type of surgery, your general fitness (including any other medical problems you may have), hospital resources, your preferences, and the needs and preferences of your surgeon. 

The choice of a particular anesthetic technique is normally a decision made by your anesthesiologist. The main concern of your anesthesiologist is your safety. In some cases your anaesthesiologist will recommend an anesthetic that is most suitable on that basis alone. In other cases there are different benefits and risks with the different anesthetics and knowing your preferences or the preferences of your surgeon become important in helping make the best choice for you. 

You are the ultimate decision-maker and your anesthesiologist and surgeon cannot proceed with the anesthesia and the operation without your agreement and your informed consent. 

What is general anesthesia? 

General anesthesia provides unconsciousness so you do not feel, see, or hear anything during a surgical procedure. The anesthetic medications are given through an intravenous (IV) line (drip) or as a breathing gas mixed with air or pure oxygen. 

The state of unconsciousness achieved during general anaesthesia reduces, or eliminates completely, your body’s observed reactions to a painful stimulus, like a surgical knife. The results of general anesthesia include the blocking of pain, of awareness, and of muscle movements. Reactions of the so-called “autonomic nervous system” like increased heart rate, blood pressure and sweating are also blocked. 

In many cases, drugs with pain-killing properties, such as morphine, are used as part of the “mix” of anesthetic drugs. 

During general anesthesia muscle relaxing drugs are often given to make absolutely sure your muscles do not naturally contract, which would make surgery difficult. An artificial airway (breathing tube) must then be inserted and breathing achieved with a machine – a mechanical ventilator. 

Your anesthesiologist watches over you very closely throughout the entire procedure with sophisticated technological equipment called “monitors”, as well as with close “hands-on” observation with the human senses. 

Anesthesia is maintained until the surgical procedure is over – this involves continued administration of the medications and continual adjustment of their dose, based on how you respond. A fixed dose of anesthetic does not produce the same level of anesthesia in all patients. A person's response depends on age, weight, sex, general state of health or disease, genetic factors, drug interactions, and other factors. 

Recovery from anesthesia occurs as the amount of anaesthetic in the brain decreases and, ultimately, is removed from the body entirely. The gases are removed from the body mainly by breathing them out, and the intravenous drugs by the action of the liver and kidneys. The effect of the muscle relaxing drugs is usually ended by giving other “reversal” drugs. 

After waking up from anesthesia, you are usually transferred to a recovery area where you are monitored closely by specially trained nurses. After some major surgeries, patients may be taken to an intensive care unit for recovery. 

Depending on the surgery and the type of anesthesia used, many people are able to go home within 1 - 4 hours. In this case the person who has had anesthesia must have a responsible adult companion provide an escort home and ideally care at home for the first 24 hours or so after surgery. 

What are the risks of general anesthesia? 

Some people may experience nausea and vomiting afterwards. In people who are susceptible this can be quite annoying, but treatment is available. Other after-effects or problems that can occur with general anesthesia include sore throat, tooth damage, headache, drowsiness or dizziness. Severe problems or even death can occur with general anesthesia but are rare, especially in healthy people. 

For more detail on the risks that apply to you, please talk with your anesthesiologist. 

What is regional anaesthesia?  

 In this form of anesthesia, so-called “local” anesthetic medications are injected to numb the nerves that supply sensation to the operated-on body part. Lidocaine, and the old “Novocain” (procaine) are examples of local anesthetics.  

 The nerves are “blocked”, meaning that they cannot transmit their signals during the time the anesthetic is active.  

 Regional anesthesia relies on the anesthetic drug being placed in exactly the right part of the body, close to the nerve, or bundle of nerves, or the spinal cord. If good positioning is not achieved, the regional anesthesia will not work well or may not work at all. General anesthesia may then be necessary.  

 To assist in the accurate placement of the regional anesthesia needle a machine called a nerve stimulator may be used. The electricity it sends into the needle makes muscles twitch. Ultrasound machines can also be used to help find the nerves and increase the chances of a successful block. The needle is normally inserted with the patient awake so small amounts of sedation medicine are often given to decrease discomfort at this time.  

Epidural anaesthesia is a form of regional anaesthesia in which a narrow tube, (also called a catheter) is placed in the epidural space in your back. The epidural space is a part of the spinal canal that is in close contact with nerves. By injecting anesthetic medication into this space, the spinal nerves are numbed. An epidural requires the insertion of a special needle into the back. The epidural needle can be inserted with very little discomfort by an experienced practitioner, using local anesthesia to numb up the skin and tissues of the back. When the needle is in place, the epidural catheter is threaded through the needle and the needle is then removed.  

A spinal anesthetic is an alternative to the epidural technique. A special needle is inserted in the lower part of the back, and local anesthetic medication is injected through the needle directly into the fluid that bathes the spinal nerves. The needle is then removed. No catheter is involved.  

The effects of spinal and epidural anesthesia, and of other regional anaesthesia techniques, are very similar - they temporarily block nerve signals, so that pain is not felt. As well as blocking sensation, these anesthetic techniques usually also decrease the ability to move part of the body. As the medication wears off, the affected parts recover both sensation and movement.  

The recovery time depends on the dose and type of local anaesthetic used and can range from an hour or less, to more than 12 hours. The time that the block is effective can also be prolonged if needed by inserting a catheter through which local anesthetic is continually administered.  

Sedation is often given along with regional anesthesia to provide comfort but some patients, with the consent of anaesthesiologist and surgeon, may choose to remain completely awake during regional anesthesia and surgery.  

What are the risks of regional anesthesia?  

Problems that can occur with regional anesthesia include temporary or permanent nerve injury (rare), headache, backache, infection, reactions to the medication (“toxicity”) or allergic reactions. Severe problems, and death, are as uncommon as with general anesthesia but can occur.  

For more detail on the risks that apply to you, please talk with your anesthesiologist. 

Sedation techniques include “mild”, “moderate” and “deep sedation”. A variety of other terms are also used, such as ”monitored anesthesia care” (MAC), “conscious sedation” and “twilight sleep”. These techniques differ from general anesthesia in that patients are more likely to respond to pain (which is why local anesthesia will often be used also), are able to breathe more easily without the assistance of a breathing tube or ventilator, and show less effect on the heart and blood pressure. 

Sedation techniques usually involve: 

    * Administration of intravenous anesthetic drugs 

    * Oxygen (given with a nasal cannula or face mask) 

    * Standard patient monitoring procedures similar to those used during a general anesthetic 

Because sedation usually involves the administration of lower doses of anesthetic drugs than with a general anesthetic, the recovery period tends to be shorter. The drugs that are used affect your ability to remember the procedure, but periods of awareness are likely to occur. 

What are the risks of sedation?  

A fixed dose of anesthetic medication does not produce the same level of sedation in all persons. A particular person’s response depends on age, weight, sex, general state of health or disease, genetic factors, drug interactions, and other factors.  

Because of this unpredictability a patient undergoing sedation may on occasion enter the “zone” of general anesthesia. The anesthesiologist must then be able to provide support for the airway (such as a breathing tube), breathing (such as a mechanical ventilator) and the heart and blood pressure (such as a resuscitation drugs). This is known as the ability to “rescue” from general anaesthesia and is one of the main reasons why sedation is risky when undertaken by unqualified personnel in poorly equipped settings.  

The possible complications of sedation are similar to those of general anesthesia, but are usually fewer in number and less in severity, provided patients are not severely ill or unsuited to receive sedation for some other reason.  

Some people may experience nausea and vomiting afterwards. In patients who are susceptible this can be quite annoying, but treatment is available. Other after-effects or problems that can occur with sedation include sore throat, tooth damage, headache, drowsiness or dizziness. Severe problems or even death can occur with sedation but are extremely rare, especially in healthy people.  

For more detail on the risks that apply to you, please talk with your anesthesiologist.