In a consideration of the chemical agents to be used in preparing a patient for an operation, three factors are of importance:
1. Which anesthetic agent (basis) is to be used?
2. Which of the nonvolatile agents (adjuvants) should be used to produce the preanesthetic depression of the central nervous system?
3. Which agents (correctives) should be used to prevent or counteract certain undesirable side reactions produced in the patient by the main anesthetic agent to be employed?
It is a discussion of the agents used as adjuvants and correctives and the reaction of the body to their administration that is to follow.
ADJUVANTS FOR DEPRESSION OF THE CENTRAL NERVOUS SYSTEM
The almost universal custom of producing moderate depression of the central nervous system in patients before administration of the major anesthetic agent is based in part on the following points:1. The production of a quiet mental state before