AGENTS USED DURING SURGERY
Section I. GENERAL ANESTHETIC AGENTS
a. Have you ever undergone surgery? If you have, you can readily appreciate
the importance of drugs used during surgery. This group of agents is widely used. The
agents within the group differ widely in their uses and indications. This lesson will focus
on this group of drugs with the intent of giving you a background in this important area.
b. In days gone by, various substances (that is, whiskey) were used to "put the
patient to sleep" during surgery. As surgical procedures became increasingly
sophisticated, the need for better anesthetic agents became more apparent. Today,
general anesthetic agents comprise an important group of pharmacological agents.
Their use promotes patient welfare. This section of the subcourse will discuss this
important group of agents.
A general anesthetic is an agent that depresses the central nervous system
reversibly, producing loss of consciousness, analgesia, and muscle relaxation, with
minimal depression of the patient's vital functions. That is, a general anesthetic agent
places the patient in a state of anesthesia in which his muscles are relaxed and he feels
no pain. Later, after the procedure has been completed, the patient can regain
consciousness and recuperate.
6-3. MECHANISM OF ACTION OF GENERAL ANESTHETICS
It is known that the general anesthetic agents depress the central nervous
system. Precisely how this depression occurs is unknown. Several theories attempt to
explain this depression. One-theory states the agents affect lipid (fat) structures in the
brain in order to produce the central nervous system depression. If you desire a
detailed discussion of the various theories, you should consult a pharmacology text.
6-4. TYPES OF GENERAL ANESTHETIC AGENTS
There are two broad types of general anesthetics: The inhalation agents and the
intravenous agents. It is not the purpose of this subcourse to provide a complete listing
or a detailed discussion of the agents that are presented. If you desire additional
information on these agents, you should consult a pharmacology text.