Ch 27 General Anesthetics

Question 1

General anesthetics produce __.

Answer 1

unconsciousness and insensitivity to painful stimuli.

In contrast, analgesics reduce sensitivity to pain but do not reduce consciousness.

Question 2

The term balanced anesthesia refers to __.

Answer 2

the use of several drugs to ensure that induction of anesthesia is smooth and rapid and that analgesia and muscle relaxation are adequate.

Question 3

The ___ of an inhalation anesthetic is defined as the minimum concentration of drug in alveolar air that will produce immobility in 50% of patients exposed to a painful stimulus.

Answer 3

minimum alveolar concentration (MAC)

A low MAC indicates high anesthetic potency!

Question 4

__ work by enhancing transmission at inhibitory synapses and by inhibiting transmission at excitatory synapses.

Answer 4

Inhalational agents

Question 5

__ are eliminated almost entirely in the expired air.

Answer 5

Inhalation anesthetics

As a rule, they undergo minimal hepatic metabolism.

Question 6

The principal adverse effects of general anesthetics are (2).

Answer 6

depression of respiration and cardiac performance

Question 7

Malignant hyperthermia is a rare genetically determined, lifethreatening reaction to __.

Answer 7

general anesthetics.

Coadministration of succinylcholine, a neuromuscular blocker, increases the risk of the reaction.

Question 8

By enhancing analgesia, __ reduce the required dosage of general anesthetic.

Answer 8

opioids

Question 9

By enhancing muscle relaxation, __ reduce the required dosage of general anesthetic.

Answer 9

neuromuscular blockers

Question 10

Nitrous oxide differs from other general anesthetics in two important ways:

Answer 10

(1) it has a very high MAC and therefore cannot be used alone to produce general anesthesia, and
(2) it has high analgesic potency and therefore is frequently combined with other general anesthetics to supplement their analgesic effects.

Question 11

__ is widely used alone (for diagnostic procedures) and
combined with an inhalation anesthetic (as a component
of balanced anesthesia).

Answer 11

Propofol, a rapid-acting agent with an ultrashort duration,

Question 12

__ is an IV anesthetic that produces a state known as dissociative anesthesia.

Answer 12

Ketamine

Patients recovering from ketamine may experience adverse psychologic reactions.