Types of Risks 

The risks of anesthesia may be considered in terms of side effects and
adverse effects.

A side effect is a secondary or unwanted effect of a drug or treatment.
Many side effects of anesthesia drugs and techniques can be anticipated,
but may be unavoidable. Although at times uncomfortable or distressing,
most common side effects are not particularly dangerous. They will either
wear off or can be treated easily. Examples of side effects are nausea,
vomiting, drowsiness, dizziness, sore throat, shivering, aches and pains,
discomfort during injection of drugs, and agitation upon awakening from

An adverse effect is a result of a drug or treatment that is neither intended
nor expected. Adverse effects are very rare, but may occur. These may
include dental trauma, croup (swelling of the windpipe), allergic reactions
to drugs or latex products, wheezing, vocal cord spasm or injury, regurgitation
of stomach contents with subsequent aspiration pneumonia, injury
to arteries, veins or nerves, alterations in blood pressure, and/or irregular
heart rhythms. Death and heart attack are the most feared of all
anesthetic risks, but fortunately these complications are extremely rare. In
the United States, the chance (risk) of a healthy individual of sustaining a
severe injury as a result of anesthesia is less than the risk of
traveling in a car.