General anesthesia is a treatment that renders you unconscious during medical procedures, so you don't feel or remember anything that happens. General anesthesia is commonly produced by a combination of intravenous drugs and inhaled gasses (anesthetics).
The "sleep" you experience under general anesthesia is different from regular sleep. The anesthetized brain doesn't respond to pain signals or surgical manipulations.
The practice of general anesthesia also includes controlling your breathing and monitoring your body's vital functions during your procedure. General anesthesia is administered by a specially trained physician, called an anesthesiologist, often in conjunction with a certified registered nurse anesthetist.
Why it's done
Your doctor may recommend general anesthesia for procedures that:
Other forms of anesthesia may provide light sedation or use injections to numb a region of your body selectively.
Most healthy people don't have any problems with general anesthesia. However, as with most medical procedures, there is a small risk of long-term complications and, rarely, death. Specific complications are related to the type of procedure and your general physical health.
Additionally, the following factors can increase your risk of complications:
The following complications are rare and occur more frequently in older adults or in people who have medical problems:
The following factors appear to make this phenomenon — also called unintended intraoperative awareness — more likely:
How you prepare
General anesthesia blunts your body's natural inclination to retain food in your stomach and keep it out of your lungs. That's why it's important to follow your doctor's instructions about when to stop eating and drinking prior to surgery. In most cases, you should start fasting about six hours before your procedure.
Your doctor may tell you to take certain medications with a small sip of water during your fasting time. You may need to avoid some medications, such as blood thinners like aspirin, for at least a week before your procedure. Some vitamins and herbal remedies also keep your blood from clotting normally, so discuss the types of dietary supplements you take with your doctor.
If you have diabetes, talk with your doctor about altering your diabetes medication during the fasting period. Usually you will not take oral diabetes medication the morning of surgery, and if you take insulin a reduced dose will be recommended.
If you have sleep apnea and use a continuous positive airway pressure (CPAP) machine bring it with you to the surgery. As you awaken from anesthesia the CPAP machine can help you breathe more normally.
What you can expect
Before general anesthesia
The information you provide will help the anesthesia specialist choose the drugs that will work best and be safest for you.
During general anesthesia
A member of the anesthesia care team monitors you continuously during your procedure, adjusting your medications, breathing, temperature, fluids and blood pressure as needed. Any abnormalities that occur during the surgery are corrected by administering additional medications, fluids and, sometimes, blood transfusions.
After general anesthesia
Last Updated: 2010-06-26
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