General Anesthetics

Question 1

What 2 categories of responses can be triggered by stimulation?

Answer 1

1. somatic (sensory, motor)
2. autonomic

Question 2

Which response is triggered by very painful (noxious) stimuli?

Answer 2

autonomic

Question 3

Which requires the greatest anesthetic depth/levels (i.e. general anesthesia) to suppress it?

Answer 3

autonomic responses

Question 4

How are factors like anxiety, responsiveness, consciousness, pain perception and memory affected by the depth of anesthesia?

Answer 4

as anesthetic depth increases, anxiety, responsiveness, consciousness, pain perception and ability to remember the event diminish

Question 5

What are the five goals of general anesthesia?

Answer 5

1. unconsciousness
2. amnesia (no memory of experience)
3. analgesia (no pain from noxious stimulus)
4. immobility in response to noxious stimulus
5. no autonomic response to noxious stimulus

Question 6

Does every general anesthetic produce all 5 goals of anesthesia?

Answer 6

All produce unconsciousness, some general anesthetic drugs produce all 5 effects, others only one or two

Question 7

Balanced anesthesia

Answer 7

administration of a combination of drugs to provide more complete anesthesia than possible with one agent alone, and to minimize dose-dependent side effects of each drug

Question 8

2 major routes of administration of general anesthetics

Answer 8

IV and inhalation

Question 9

Volatile anesthetics (halogenated agents)

Answer 9

liquid at room temperature, evaporate easily

Question 10

Gaseous anesthetics

Answer 10

gasses at room temperature

Question 11

Induction agents

Answer 11

those used to bring patients to desired level of anesthesia (IV agents are preferred for this purpose)

Question 12

Maintenance agents

Answer 12

those used to maintain patients at the correct level of anesthesia (inhaled agents preferred for this purpose)

Question 13

Two main mechanisms of general anesthetics at the cellular level

Answer 13

1. altering synaptic transmission
2. hyperpolarization of neurons

Question 14

Which category of general anesthetics act directly at synapses?

Answer 14

IV and inhaled

Question 15

What 3 neurotransmitter systems are mainly affected by general anesthetics that act directly at synapses?

Answer 15

GABA, glycine, and glutamate

Question 16

Which category of general anesthetics hyperpolarizes neurons by unknown mechanisms?

Answer 16

inhaled agents make neurons less likely to produce action potentials

Question 17

3 neurotransmitter receptors that are mainly targeted by general anesthetics

Answer 17

1. NMDA glutamate receptor
2. GABA(a) receptor
3. glycine receptor

Question 18

Which 1 neurotransmitter receptor is the most common target of general anesthetics?

Answer 18

GABA

Question 19

Which 1 neurotransmitter receptor is the least common target and which 2 anesthetics act at this receptor?

Answer 19

NMDA
ketamine and gaseous anesthetics

Question 20

What two categories of side effects are produced by nearly all general anesthetics?

Answer 20

changes in heart rate and blood pressure; decrease in blood pressure and increase in heart rate

Question 21

Which 1 general anesthetic is essentially free of cardiovascular effects?

Answer 21

Etomidate

Question 22

Which 1 general anesthetic is essentially free of respiratory effects?

Answer 22

Ketamine

Question 23

What 4 categories of side effects are possible with general anesthetics?

Answer 23

1. altered cerebral blood flow, volume, and metabolic rate
2. nausea and vomiting
3. hypothermia
4. emergence agitation

Question 24

What 3 categories of side effects are possible with all volatile inhaled anesthetics and which 1 of these is useful?

Answer 24

1. malignant hyperthermia
2. relaxation of skeletal muscle (useful)
3. reduction of clearance organ blood flow