Anesthesia Student Survival Guide.pdf - Index of

Chapter 5
Pharmacology of Inhalational Anesthetics
Jerome M. Adams and John W. Wolfe
For maximum impact, it is recommended that the case study and questions found
on page xix are reviewed before reading this chapter.
Key Learning Objectives
● Learn the pharmacokinetic factors affecting the rate of induction and
emergence with inhalational anesthetics
● Understand the concept of Minimum Alveolar Concentration (MAC)
● Know the key characteristics of the four most commonly used inhalational
agents (nitrous oxide, isoflurane, desflurane, sevoflurane)
The inhalational anesthetics (nitrous oxide and various volatile halogenated
ethers) play a key role in current anesthetic practice. They provide rapid induction
of anesthesia, rapid titratability during the anesthetic, and rapid emergence
at the conclusion of the anesthetic. At clinically relevant doses, the volatile
anesthetics provide reliable amnesia, immobility, a modest degree of muscle
relaxation, and blunting of the adrenergic response to surgical stimulation.
Pharmacokinetics of Uptake, Distribution and Elimination
Induction: In order to have an effect on the patient, inhalational anesthetics
must be:
1. Inspired after having been delivered from the breathing circuit
2. Absorbed from the alveoli into the blood
3. Transported from the lungs to the target tissue
4. Absorbed from the blood into the target tissue (i.e. the brain)
J.M. Ehrenfeld et al. (eds.), Anesthesia Student Survival Guide: A Case-Based Approach,
DOI 10.1007/978-0-387-09709-1_5, © Springer Science+Business Media, LLC 2010
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