Definition General anaesthesia is a method used to stop pain from being felt during a procedure or surgery. In this form of anaesthesia, medication is given to make the person unconscious.
Who is a candidate for the procedure? General anaesthesia is the most powerful form of anaesthesia. It is usually reserved for major surgery, such as surgery inside the skull, neck, chest, abdomen, and pelvis. Other procedures may also require general anaesthesia.
How is the procedure performed? General anaesthesia uses medication to make a person unconscious. Medications are commonly breathed into the lungs or injected into the veins through an intravenous line inserted into the vein of the hand or arm. An individual may also be paralysed with other medications to prevent movement during the surgery.
A ventilator, or artificial breathing machine, breathes for the person during the procedure. This is because the chest muscles are paralysed. A ventilator requires a tube to be put into the windpipe, known as endotracheal intubation. The tube goes through the mouth and into the windpipe. Oxygen and inhaled medication can then be delivered to the lungs.
The person is watched closely during the procedure. The oxygen levels in the blood, pulse, blood pressure and other functions are monitored. Fluids are usually given through an intravenous line to prevent dehydration and low blood pressure.
The individual is totally asleep and unable to feel pain during the surgery. When the procedure is complete, the medication is turned off. The person will have no memory of the surgery when he or she wakes up.
What happens right after the procedure? The person is taken to an area called the recovery room after the procedure. When the person can breathe independently, the ventilator is turned off. It may take several minutes for the person to wake up and he or she may feel groggy at first. Doctors and nurses monitor the person in the recovery room. Analgesics are given as needed. Gradually, the person wakes up and begins the recovery process.
The person may need to stay in the hospital for a few days to recover from the procedure. Often the person can go home after a few hours. The person must be stable and feel well enough to go home, and someone must be available to drive the person home. The medications cause co-ordination problems and slowed reflexes for several hours after surgery. As a rule no-one should drive on the same day as receiving a general anaesthetic.
What happens later at home? After getting home, the person should rest for the remainder of the day. By the next day, the anaesthesia is usually out of the system. The following day, the pain from the surgery usually causes more problems than the anaesthesia. Some people may take a few days to feel that they are back to normal.
What are the potential complications after the procedure? The most feared complication of general anaesthesia is death. This occurs in roughly 1 out of every 10,000 people. It is not possible to predict who will have this type of severe reaction.
The medications used in general anaesthesia can cause severe reactions. These include:
Nausea is fairly common for a few hours after the procedure. Other side effects may occur, depending on the medication used.
Anesthesiologists have warned of the potential side effects and interactions of herbal remedies with medications used before, during, and after surgery. The group recommends that a person stop taking all herbs at least two weeks before planned surgery.
Other complications are possible, such as damage to the mouth or throat from the breathing tube. The surgery itself may also have complications.
Author: Adam Brochert, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request