An anesthesia nurse administers medication to a burn victim.

U.S. Air Force photo by SSGT C. E. LEWIS, USAF

Anesthesia is a mysterious concept to most of us, even if we've been anesthetized before. The term comes from the Greek for "loss of sensation," but that's not the only effect it causes in your body. Anesthesia, essentially a reversible condition induced by drugs, is intended to result in one or more different states of being. It can relieve pain, give you amnesia to knock out your memory of the procedure or how it felt, reduce anxiety (because who doesn't have anxiety when undergoing a medical procedure?) and paralyze your muscles.

It sounds a little scary, but anesthesia is made as safe as possible by careful calculation of the required dosages and diligent monitoring by medical professionals. And not all types of anesthesia are created equal.

When you think of anesthesia, it's likely you think of what's called general anesthesia, which is when you're completely unconscious during a medical procedure such as a major surgery. But there are several different types, and not all of them leave you oblivious to the world. Local anesthesia, for example, can affect just a small patch of skin. Which type you receive depends on a number of factors, including what kind of medical procedure you need and what your medical history looks like. There can also be some overlap between different types of anesthesia, and often, more than one drug is necessary to produce all the desired effects.

In this article, we will look at the different types of anesthesia so that you can understand what it is, how it works and what risks are involved. We'll also learn about anesthesia awareness and talk about the history of anesthesia (and what it has to do with cocaine). Let's start by looking at procedural sedation, also known as "twilight sleep."