Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Pharmacology Exam 4 > Inhaled Agents Pt. 1 > Flashcards

Inhaled Agents Pt. 1 Flashcards

0
Q

**What is Woodbridge’s definition of general anesthesia?

A

General anesthesia is depression of sensory, motor, reflex and mental function.
-Includes analgesia, skeletal muscle relaxation, freedom from troubled reflexes (tachycardia, airway protection, salivation), and unconsciousness(hypnosis & amnesia) either present or not.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
1
Q

What is the easiest sign of lightness that is abolished by muscle relaxants?

A

Withdrawal from noxious stimuli

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What’s Prys-Robert’s definition of anesthesia?

A

State in which, as a result of DRUG-INDUCED UNCONSCIOUSNESS, the patient neither perceives nor recalls unpleasant stimuli.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Between somatic response to noxious stimuli and autonomic response, which is easier to suppress?

A

Somatic (Sensory/ pain& motor/ movement)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is included in the autonomic response to noxious stimuli?

A

Breathing, hemodynamics, sudomotor, and hormonal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Recognition of unconsciousness is measured by_______ not______

A

Recognition of unconsciousness is measured by side effects not what’s going on in the mind

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does the word “anesthesia” mean?

A

Greek: “an” means “without”, “sthesia” means “feeling”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Which type of anesthesia is more reliable: rgional, general, or spinal?

A

General

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Name & define stage I of anesthesia

A
  • “Analgesia & Sedation”
  • VA’s not used to produce this stage, except for N2O in dental
  • protective reflexes intact
  • eyes open to command, tolerate mild pain, normal breathing
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Name & define stage 2 of anesthesia

A
  • “Excitement”
  • Associated with MAC awake
  • Rarely seen @ induction with increased VA’s dosing & induction agents
  • More so seen on emergence (transitions quickly)
  • Muscle movement, retching, heightened laryngeal reflexes, increased HR, B/P, Ve
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Define MAC awake

A
  1. 3-0.4 MAC
    - the point below which subjects respond to command; above which they are amnestic. (point of opening eyes & following commands)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Name & define stage 3 of anesthesia

A
  • “Surgical Anesthesia”
  • MAC= that level of agent where there is no movement in response to skin incision in 50% of patients
  • Also associated with MAC95 & MAC bar
  • No behavior pain response
  • Amnesia
  • Reflex depression (HR, B/P, airway protection)
  • Skeletal muscle relaxation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Define MAC 95

A

at 1.3 MAC, 95% of patients will not move

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Define MAC BAR (Block autonomic response)

A

Taking a higher concentration to “block autonomic response” in response to highly-stimulating events.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why is assessing depth beyond MAC difficult?

A

Clinical signs of each VA differ beyond MAC, especially when modified by adjuvant drugs & PMH. Effects of drugs are also modified by time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

***What are the primary means to assess depth?

A
  • Clinical signs: SBP (though this is monitoring a side effect); movement, and respirations, which is the best sign
  • Electronic monitoring: BIS monitor, End Tidal Gas analysis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the clinical signs that gauge anesthesia depth

A
  • Respiratory (Increased RR & decreased Tv)
  • Eye signs (Lacrimation, eye movement, change to disconjugated usually suggests light anesthesia)
  • Motor (Active expiration=light, soft abd. = deep enough)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Is BIS monitoring a monitoring standard for the ASA or AANA?

A

No

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is a monitoring standard for the ASA & AANA

A

End Tidal Gas analysis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are some potential risk factors that would require less anesthetic admin. and/ or pt. at risk of becoming “light” or aware during case.

A
  • Trauma
  • Cardiac Sx.
  • Emergency Sx.
  • Cesarean Section
  • Paralysis
  • Planned use of muscle relaxants
  • Planned “Garbage”/ balanced Anesthesia (N2O & opioids)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the 3 levels End Tidal agent that examines VA that helps infer unmeasured alveolar & brain tension of VA

A

The time & relationship between:

  1. Dial setting
  2. Inspired VA
  3. Expired VA ( proportional to alveolar, arterial & brain once pt. is in equilibrium.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How does the level of anesthetic in the brain relate to the amount of agent shown on End tidal agent gas analyzer?

A

-It lags behind a few minutes (at induction the brain won’t have as much as shown on monitor. at emergence, brain will have more than what’s on monitor)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How has halogenation influenced volatile agents

A
  • Non-flammatory
  • Decreased blood solubility
  • Increased onset and offset
  • Increased resistance to metabolism & degradation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How does using only fluorine effect the VA? Which agent only uses fluorine?

A
  • Desflurane

- Nonflammable, with low solubility, and extreme resistance to metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What does low blood solubility yield?

A
  • Rapid induction
  • More precise control
  • Rapid offset
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What drives the cost of anesthetics

A

-Price per mL
-Inherent characteristics (vapor pressure, potency, solubility)
-Fresh gas flow
(Increased potency= increased cost)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What cost factor is under the control of the anesthetist

A

Fresh gas flow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Which agent boils at room temperature?

A

Desflurane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Which agent has the highest vapor pressure: N2O, Desflurane, or Sevoflurane?

A

Desflurane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Which VA is the most potent?

A

Isoflurane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Which VA is the least potent?

A

Desflurane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Of all the VA we use, which 2 should have the quickest offset/ onset?

A

-Desflurane & N2O

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What’s the boiling point of N2O

A

-it’s a gas so it doesn’t have one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What’s the MAC of Isoflurane

A

1.17%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What’s the MAC of Desflurane

A

6.6 (6)

35
Q

What’s the MAC of Sevoflurane

A

1.8 (2)

36
Q

What’s the MAC of Enflurane

A

1.63

37
Q

What’s the MAC of N20

A

104

38
Q

What is the Blood: gas partition coefficient of N2O

A

0.46

39
Q

What is the Blood: gas partition coefficient of Enflurane

A

1.90

40
Q

What is the Blood: gas partition coefficient of Isoflurane

A

1.46

41
Q

What is the Blood: gas partition coefficient of Desflurane

A

0.42

42
Q

What is the Blood: gas partition coefficient of Sevoflurane

A

0.69

43
Q

What is the Vapor Pressure of Enflurane

A

172

44
Q

What is the Vapor Pressure of Isoflurane

A

240

45
Q

What is the Vapor Pressure of Desflurane

A

669

46
Q

What is the Vapor Pressure of Sevoflurane

A

170

47
Q

How does blood gas coefficient influence the effect of VA

A

The less the BGC> the less soluble the VA is in the blood> the quicker it goes into/ out of the brain> the faster onset/ offset

48
Q

Define MAC

A

The minimum alveolar concentration which produces no movement in response to surgical stimulation in 50% of patients

49
Q

What is the percentage of MAC dependent on?

A
  • Age
  • Temperature
  • Atmospheric pressure
50
Q

Characteristics of N2O

A
  • Commonly admin. alone (sedation) or w/ opioids or VA for GA
  • Nonflammable, but supports combustion like O2
  • Low molecular wt., low potency (MAC 104%), Low BGSC (0.46)
  • Odorless to sweet odor
51
Q

N20 Advantages

A
  • Poor gas solubility = rapid alveolar pressure & brain tension
  • Good Analgesic (equal to MSO4 10mg SC)
  • Additive MAC with VA’s lead to lower cost by decreasing VA
52
Q

Disadvantages of N2O

A

-Minimal skeletal muscle relaxation
-Increased role in PONV
-High problems r/t high volume absorption
-Supports combustion (though it’s nonflammable)
-Toxic effects
-

53
Q

What are the toxic effects of N2)

A

*** depresses methionine synthetase (decreased DNA synthesis, polyneuropathy, B12). Leads to birth defects

  • Immunity (decreased PMNs & chemotaxis)
  • addictive potential
  • Greenhouse effect
54
Q

Halothane characteristics worth noting

A
  • **Metabolized in liver >20% (very high)
  • Needs a preservative d/t susceptible to decomposition so 0.01% thymol added as a preservative

-Increase blood solubility> slower offset/ onset

55
Q

What is the “Gold Standard” for volatile agents

A

Isoflurane

56
Q

Chemical make up of isoflurane

A
  • Halogenated methyl ethyl ether.

- isomer of enflurane

57
Q

***Why is Isoflurane limited in its usefulness for inhaled induction?

A

It’s pungency causes coughing in awake people

58
Q

How does Desflurane’s chemical structure differ from Isoflurane and what are the effects?

A
  • The Chlorine in Isoflurane is substituted for a Fluorine on alpha-ethyl carbon.
  • More stable & resistant to metabolism than Isoflurane
  • Onset/ offset is 1/3 of Isoflurane
59
Q

Disadvantages of desflurane

A
  • expensive
  • Pungency causes airway irritation, cough, salivation, breath-holding, and laryngospasm in awake patients.
  • ***Carbon monoxide generated in soda lime
60
Q

***Opioid effect on MAC

A

Decreases MAC significantly

61
Q

What patient population would receive the highest MAC dose

A

Newborns

62
Q

Characteristics of Sevoflurane

A
  • Least irritating r/t not pungent
  • bronchodilator
  • Slower onset & offset than Des
  • Low BGSC & MAC
  • No CO in soda lime
63
Q

Disadvantages of Sevoflurane

A
  • *****Degraded by soda lime
  • Cost
  • Metabolism 5% (Fluoride ion-potential RENAL TOXICITY)
  • Forms compound A after degraded in soda lime which is nephro toxic
64
Q

Cautions to administering Fluorine r/t FGF & MAC

A

Do not go below 2L/min FGF. If so, don’t give MAC >2.

insert states <2L/min

65
Q

Are MAC doses set or additive? If so, how?

A
  • Additive

- 1/2 MAC N2O + 1/2 MAC VA= 1 MAC

66
Q

Are the dose response curves for all VA broad or steep

A

Steep (1MAC= 50%; 1.3 MAC= 95%; 2 MAC side effects prominent & dangerous)

67
Q

As far as the dose response curve, do we measure MAC on the dial or expired MAC?

A

expired MAC

68
Q

Are you aloud to mix VA, like change to a different agent in the middle of a case?

A

No except for N2O

69
Q

What is the result of maintaing MAC at a high dose (>2)

A

Death/ damage

70
Q

How is MAC effected per decade of age

A

Decreases 6% per decade

71
Q

***How do VA produce progressive depression of CNS function

A

Unknown
(? immobility mediated @ spinal cord; amnesia probably mediated supra-spinally; RAS a likely target; effects on voltage-gated and ligand-gated ion channels?)

72
Q

***What are the effects of almost all injected & inhaled anesthetics on GABA?

A

enhance GABA

73
Q

***What is the only anesthetic that doesn’t enhance GABA activity

A

Ketamine

74
Q

Which receptor has a probable role in immobility

A

GABA

75
Q

Which measurement on gas analysis of VA is more/ less proportional to alveolar, arterial, and brain once patient is in equilibrium with outflow?

A

Expired VA

76
Q

How has halogenation effected anesthetic gases

A
  1. decreased flammability
  2. Low (plasma) solubility
  3. Extreme resistance to metabolism/ degradation (r/t #2)
  4. quicker onset & offset
77
Q

Which agent is not as stable in soda lime

A

sevoflurane

78
Q

Which agent has the lowest boiling point?

A

Desflurane (room temp)

79
Q

Which agent is the most potent

A

Isoflurane

80
Q

Which agent is the least potent

A

Desflurane

81
Q

Which agent has the highest vapor pressure

A

Desflurane (669)

82
Q

What does the blood:gas solubility determine?

A

the rate of equilibration of the amount between the blood & gas phases

83
Q

how would an agent with low blood-to-gas partition coefficient equilibrate compare to an agent with a high blood:gas partition coefficient? (O&J p. 165)

A

the low blood: gas will equilibrate more rapidly

84
Q

Patient factors that influence effects $ side effects of VA

A
  1. age
  2. coexisting dz.
  3. medications
  4. intravascular fluid volume
  5. body temp
85
Q

Which 2 VA are most alike

A

Desflurane & Isoflurane (Des has aF for Cl on alpha-ethyl carbon). They often have same properties and effect in body.

86
Q

How is apprehension HTN in preop affected by VA

A

Exaggerated hypotension

Pharmacology Exam 4 (2 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions