This information is written by the Royal College of Anesthesiologists of Great Britain (www.rcoa.ac.uk)
Anesthetic risks are thought of in terms of side effects and complications.
Side effects are secondary effects of drugs or treatment. They can often be anticipated but are sometimes unavoidable. Almost all treatments (including drugs) have side effects of some kind. Unpleasant side effects do not usually last long. Some are best left to wear off and others can be treated. Examples would be a sore throat or sickness after a general anesthetic.
Complications are unexpected and unwanted events due to a treatment. Examples would be an unexpected allergy to a drug or damage to your teeth caused by difficulty in placing a breathing tube. The risk of something happening to one in 10 people means that, it will not happen to nine out of 10 people.
- Index of side effects and complications:
People vary in how they interpret words and numbers. This scale is provided to help:
Very common (1 in 10) / Common (1 in 100) / Uncommon (1 in 1,000) / Rare (1 in 10,000) / Very rare (1 in 100,000)
If something is:
• Very common, this means that about one in 10 will experience it
• Common means about one in 100
• Uncommon means about one in 1000
• Rare means about one in 10,000
• Very rare means about one in 100,000 (which is the risk of dying by gun shot in the streets of Dubai.)
This index is divided into three sections which relate to the scale. There is also a key to show which side effect or complication is relevant to which type of anesthetic.
RA = this may occur with a regional anesthetic.
GA = this may occur with a general anesthetic.
- Very common and common side effects and complications:
Feeling sick and vomiting after surgery** GA RA
Some operations, anesthetics and pain-relieving drugs are more likely to cause sickness (nausea) than others. Sickness can be treated with anti-vomiting drugs (antiemetics), but it may last from a few hours to several days.
Sore throat** GA
If you have had a tube in your airway to help you breathe, it may give you a sore throat. The discomfort or pain lasts from a few hours to days and can be treated with pain-relieving drugs.
Dizziness and feeling faint GA RA
Your anesthetic may lower your blood pressure and make you feel faint. This may also be caused by dehydration (when you have not been able to drink enough fluids). Fluids or drugs (or both) will be put into your drip to treat this.
Shivering** GA RA
You may shiver if you get cold during your operation. Care is taken to keep you warm during your operation and to warm you afterwards. A hot-air blanket may be used. However, shivering can happen even when you are not cold, due to the effects of anesthetic drugs.
Headache** GA RA
Headaches have many causes which include the anesthetic, the operation, dehydration and anxiety. Most headaches get better within a few hours and can be treated with pain-relieving medicines. Severe headaches can happen after a spinal or epidural anesthetic (see the leaflet about this listed on the inside front cover of this booklet DELETE???). If this happens to you, your nurses should ask the anesthesiologist to come and see you. You may need special treatment to cure your headache.
Itching GA RA
This is a side effect of opiates (such as morphine), but can be caused by an allergy (for example, to drugs, sterilizing fluids, stitches or dressings). If you have itchiness, it can be treated with other drugs.
Aches, pains and backache GA RA
During your operation you may lie in the same position on a firm operating table for a long time. Great care is taken to position you, but some people still feel uncomfortable afterwards.
Pain GA RA
Drugs may cause some pain or discomfort when they are injected.
Bruising and soreness GA RA
This may occur around the injection and drip sites and is caused by the bursting of a thin vein, movement of a nearby joint, or by an infection. It normally settles without treatment, but if the area becomes uncomfortable, the position of the drip can be changed.
Confusion or memory loss** GA
This is common among older people who have had an operation under general anesthetic. It may be due to several causes. It is usually temporary, but may sometimes be permanent.
Chest infection** GA
A chest infection is more likely to happen to people who smoke, and may lead to breathing difficulties. This is why it is very important to give up smoking for as long as possible before your anesthetic.
Bladder problems GA RA
After certain types of operation and regional anesthesia (particularly with a spinal or epidural), men may find it difficult to pass urine, and women tend to leak. To prevent problems, a urinary catheter may be inserted at a suitable time.
Muscle pains GA
These sometimes happen if you have received a drug called suxamethonium. This is a muscle relaxant which is given for emergency surgery when your stomach may not be empty.
Uncommon side effects and complications
Breathing difficulties GA RA
Some pain-relieving drugs can cause slow breathing or drowsiness after the surgery. If muscle relaxants are still having an effect (have not been fully reversed), the respiratory muscles may be weak. These effects can be treated with other drugs.
Damage to teeth, lips or tongue** GA
Minor damage to your lips and tongue is common. Damage to your teeth is uncommon, but may happen as your anesthesiologist places a breathing tube in your airway. It is more likely if you have weak teeth, a small mouth, a stiff neck or a small jaw.
Worsening of an existing medical condition GA RA
Your anesthesiologist will always make sure that you are as fit as possible before your surgery. However, if you have had a heart attack or stroke, it is possible that it may happen again – as it might even without the surgery. Other conditions such as diabetes or high blood pressure will also need to be closely monitored and treated.
Awareness is becoming conscious during some part of an operation when under general anesthetic. It happens because you are not receiving enough anesthetic to keep you unconscious. Monitors are used during the operation to record how much anesthetic is in your body and how your body is responding to it. These normally allow your anesthesiologist to judge how much anesthetic you need to keep you unconscious. If you think you may have been conscious during your operation, your anesthetist should be told about it as soon as possible. He or she will want to know, to help both you and future patients.
- Rare or very rare complications:
Damage to the eyes** GA
Anesthesiologists take great care to protect your eyes. Your eyelids may be held closed with adhesive tape, which is removed before you wake up. However, sterilizing fluids could leak past the tapes, sheets or drapes, or you may rub your eye as you wake up after the tapes have been removed. These could cause damage to the surface of your eye, which is usually temporary and responds to drops. Serious and permanent loss of vision can happen, but it is very rare.
Serious allergy to drugs** GA RA
Allergic reactions will be noticed and treated very quickly. Very rarely, these reactions lead to death even in healthy people. Your anesthesiologist will want to know about any allergies you or your family may have.
Nerve damage** GA RA
Nerve damage (paralysis or numbness) can be caused by a needle when performing a regional anesthetic or can be due to pressure on a nerve during an operation. It varies with the type of anesthetic you have, but is generally rare or very rare. Most nerve damage is temporary, but in some cases damage is permanent.
Death** GA RA
Deaths caused by anesthesia are very rare. There are probably about five deaths for every million anesthetics given in the UK.
Equipment failure** GA RA
Vital equipment that could fail includes the anesthetic gas supply or the ventilator. Monitors give an immediate warning of problems, and anesthesiologists have immediate access to back-up equipment.