Brainscape's Knowledge GenomeTM

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


See full index

Apex > Inhaled Anesthetics: Part 1 > Flashcards

Inhaled Anesthetics: Part 1 Flashcards

1
Q

What three groups do we categorize inhaled anesthetics?

A

Ethers, alkanes, and gases

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

What are examples of ethers? For inhalers anesthetics

A

Desflurane
Isoflurane
Sevoflurane
Enflurane
Ether

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

What are examples of Alkanes? For inhaled anesthetics

A

Halothane
Chloroform

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

What are examples of gases? For inhaled anesthetics

A

Xenon
Nitrous oxide
Cyclopropane

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

How many fluorine atoms does Isoflurane?

A

5 fluorine atoms and
1 chlorine atom

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

How many fluorine atoms are in desflurane?

A

6 fluorine atoms

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

How many fluorine atoms does Sevo have?

A

7 fluorine atoms

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

Which inhaled anesthetic has a bromine atom?

A

Halothane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What is vapor pressure?

A

The pressure exerted by a vapor in equilibrium with its liquid or solid phase inside of a closed container

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is vapor pressure directly proportional to?

A

Temperature

^ temperature = ^ vapor pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is evaporation?

A

Process where a compound transitions from its liquid state to its gaseous state at a temperature below its boiling point

Vapor pressure is < atmospheric pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is boiling?

A

Boiling occurs when vapor pressure = atmospheric pressure

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

What is the equation for partial pressure of a gas?

A

Vol% x total gas pressure = partial pressure of that particular gas

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

What can Isoflurane and desflurane produce in desiccated soda lime?

A

Carbon monoxide

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

What can Sevo produce? (even in hydrated soda lime)

A

Compound A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the vapor pressure and boiling point of Sevo?

A

VP: 157
BP: 59 degrees Celsius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the vapor pressure and boiling point of Des?

A

VP: 669
BP: 22 degrees Celsius

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

What is the vapor pressure and boiling point if Isoflurane?

A

VP: 238
BP: 49 degrees Celsius

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

What is the vapor pressure and boiling point of nitrous oxide?

A

VP: 38,770
BP: -88 degrees Celsius

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the blood:gas coefficient and oil:gas coefficient of Sevo?

A

B:G ~ 0.65
O:G ~ 47

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is the blood:gas coefficient and Oil:gas coefficient for Desflurane?

A

B:G ~ 0.42
O:G ~ 19

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

What is the blood:gas coefficient and oil:gas coefficient for Isoflurane?

A

B:G ~ 1.46
O:G ~ 91

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is the blood:gas and oil:gas coefficients for Nitrous oxide?

A

B:G ~ 0.46
O:G ~ 1.4

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

What are some factors that will increase the FA/FI (wash in of anesthetic gases)

A

Increased fresh gas flows
High alveolar ventilation
Low FRC
Low time constant
low anatomical dead space

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are some factors that will decrease uptake? Aka cause a faster onset

A

Low solubility
Low CO
Low Pa-Pv difference

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

What is the vessel rich group? What does it contain and how much cardiac output does it receive? how much body mass is it?

A

Contains: heart, brain, kidneys, liver, endocrine
Body mass: 10%
CO: 75%

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

What are some factors that would cause a slower onset? Think decreased wash in

A

Low fresh gas flows
Low alveolar ventilation
High FRC
High time constant
High anatomical dead space

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

What are some factors that would cause a slower onset? Think an increase in uptake

A

High CO
High solubility
High Pa-Pv difference

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

What is the muscle group? What is it’s % mass and how much CO does it receive?

A

Contains: muscle and skin
% mass: 50
CO: 20

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

What is the Fat group? How much body mass does it contain? What % of CO does it receive?

A

Contains: fat
Body mass: 20%
CO: 5%

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

What is the hepatic biotransformation of Nitrous oxide?

A

0.004

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

What is the hepatic biotransformation of Des?

A

0.02

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

What is the hepatic biotransformation of iso?

A

0.2

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

What is the hepatic biotransformation of Sevo?

A

2-5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What is the hepatic biotransformation of halothane?

A

20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What is the FDA recommendation for Sevo and fresh gas flows?

A

FGF of 1L/min for up to 2 MAC hours and 2 L/min for > 2 MAC hrs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What byproduct of halothane s has been implicated in causing halothane hepatitis?

A

Trifluoroacetic acid (TFA)

38
Q

What is the concentration effect?

A

The higher the concentration of inhalation anesthetic delivered to the alveolus (FA), the faster it’s onset of action.

This is also called overpressuring

39
Q

Explain concentrating with Nitrous oxide.

A

Nitrous is more soluble than nitrogen (which is the primary gas in the lung)

When nitrous is introduced, volume of nitrous going from alveolus to blood is higher than nitrogen. This causes the alveolus to shrink ~ reducing alveolar volume and causing a relative increase in FA

40
Q

What is the difference if the second gas effect and the concentration effect?

A

The concentration effect deals with a single gas, the second gas effect describes the consequences of the concentration effect when a second gas is co-administered.

41
Q

The second gas effect produces a more meaningful benefit with what agents?

A

More soluble agents

ISO > Sevo > Des

42
Q

What is diffusion hypoxia?

A

It’s when the nitrous that has accumulated in the body transfer back to the alveoli for elimination. This temporarily dilutes alveolar O2 and CO2 ~ leading to hypoxia and hypocarbia

43
Q

How do you mitigate diffusion hypoxia?

A

Administration of oxygen 3-5 minutes after nitrous has been discontinued

44
Q

What type of agents are affected the most in a right-left cardiac shunt?

A

Agents with low solubility (desflurane)

Because agents like ISO are more soluble, they are more dissolved in the blood, which offsets the dilution

45
Q

How does a right-to-left shunt affect IV inductions?

A

Faster induction. Blood bypasses the lungs and travels to the brain faster

46
Q

How does a left-to-right shunt affect volatile agents?

A

Does not have a meaningful effect on anesthetic uptake

47
Q

How does a left-to-right shunt affect IV induction agents?

A

Slower IV induction

Agent is recirculating in lungs

48
Q

If SF6 is placed for a retinal detachment, when should nitrous oxide be discontinued and when can it be restarted?

A

Discontinued: 15 mins before placement
Restarted: 7-10 days after

49
Q

When should we avoid N2O after other types of bubbles?

A

Air: 5 days
Perfluoropropane: 30 days
Silicone oil: no contractindication

50
Q

What is the most realizable way to check the internal pressure of an ETT or LMA?

A

Manometer

51
Q

What vitamin does nitrous oxide irreversibly inhibit?

A

Vitamin B12, which then inhibits methionine synthase (which is required for folate metabolism and myelin production)

52
Q

Risk of complications regarding nitrous oxide and B12 is increased by what pre-existing B12 deficiencies?

A

Pernicious anemia, alcoholism, strict vegan diet, recreational use of N2O

53
Q

What is the potency of the volatile anesthetics from lowest to highest

A

Nitrous< Des< Sevo<ISO

54
Q

MAC is a measure of what?

A

Potency

55
Q

What is the MAC of all the anesthetics?

A

ISO: 1.2
Sevo: 2
Des: 6.6
Nitrous: 104

56
Q

What is MAC-awake?

A

Alveolar concentration where a patient opens his or her eyes.

0.5 during induction
As low as 0.15 during recovery

57
Q

What is MAC-bar?

A

The alveolar concentration required to block autonomic response following a painful stimulus

1.5 MAC

58
Q

When are awareness and recall generally assumed to be prevented?

A

0.4-0.5 MAC

59
Q

What are some things that increase MAC requirements?

A

Chronic alcohol consumption
Amphetamine intoxication
Cocaine
MAOIs
Ephedrine
Levodopa
Hypernatremia
Age (infants ^)
Hyperthermia
Red hair

60
Q

What are some things that decrease MAC requirements?

A

Acute alcohol
IV anesthetics
N2O
Opioids
Alpha 2 agonists
Lithium
Lidocaine
Hyponatremia
Prematurity
Old age
Hypothermia
Hypotension
Anemia
CPB
Metabolic acidosis
Hypo-osmolarity
Postpartum period
PaCO2 > 95 mmHg

61
Q

What are some things that have no effect on MAC?

A

Hypokalemia
Hypothyroid
Hypomagnesemia
Gender
Hypertension

62
Q

What is the Meyer-Overton Rule?

A

Lipid solubility is directly proportional to potency of an inhaled anesthetic

63
Q

What is the unitary hypothesis?

A

All anesthetics share a similar MOA, but each may work at a different site.

64
Q

Generally speaking, volatile anesthetics have what effects on their target receptors?

A

They stimulate inhibitory receptors
They inhibit stimulatory receptors

65
Q

What are some inhibitory pathways that volatile anesthetics stimulate?

A

GABA
glycine
Potassium channels

66
Q

What are some stimulatory pathways that volatile anesthetics inhibit?

A

NMDA
Nicotinic
Sodium channels
Dendritic spine function and mobility

67
Q

In the spinal cord, where so volatile anesthetics produce immobility?

A

Ventral horn

68
Q

Which anesthetics do NOT stimulate the GABA receptor?

A

Xenon
Nitrous

(They have NMDA antagonism)

69
Q

What are the pharmacological effects of volatile anesthetics? Think parts of the brain and spinal cord

A

Unconsciousness: RAS
Amnesia: hippocampus
Analgesia: spinothalamic tract
Immobility: ventral horn

70
Q

What so volatile anesthetics do to hemodynamics?

A

HR: increase (iso/Des/nitrous) or maintain (sevo)
BP: decrease (except Des and xenon)
CO: decrease (except xenon)
SVR: decrease (except nitrous and xenon)

71
Q

What aspect of the EKG do volatile anesthetics affect?

A

QT interval

72
Q

What is the potency of coronary artery vasodilation?

A

ISO>Des>Sevo

73
Q

How do halogenated anesthetics affect the respiratory pattern?

A

Reduce tidal volume
Increase RR
Impair response to carbon dioxide
Impair motor neuron output and muscle tone to the upper airway

(This increases dead space)

74
Q

What does a decreased response to carbon dioxide do to the CO2 response curve? What are some causes?

A

Down and to the right

Causes: volatile anesthetics
Opioids
Metabolic alkalosis
Denervation if peripheral chemoreceptors

75
Q

What happens when you increase the apneic threshold?

A

You increase the PaCO2 at which a patient is stimulated to breathe

76
Q

What are some causes of a left shift in the CO2 response curve?

A

Anxiety
Surgical stimulation
Metabolic acidosis
Increased ICP
Salicylates
Doxapram

77
Q

Which agents inhibit the hypoxic drive the most? Remember that it’s the reactive oxygen species that affect the glomus cells ~ there species occur after metabolism

A

Halothane > Sevo > ISO > Des

It goes in order of hepatic biotransformation

78
Q

What is the best agent for a patient who relies on the hypoxic drive to breathe?

A

Desflurane

79
Q

Where are the carotid baroreceptors located?

A

carotid sinus

80
Q

Where are the carotid chemoreceptors located?

A

Carotid body

81
Q

What do volatile anesthetics do to the cerebral metabolic rate?

A

Reduce it, but only to an isoelectric state

This is a 1.5-2.0 sevo MAC

82
Q

What do volatile anesthetic do to cerebral blood flow?

A

Increase it.

They uncouple CMRO2 and CBF

This can be problematic with patients with increased ICP

83
Q

How do volatile agents affect Cerebrospinal fluid volume?

A

Iso: increases absorption
Desflurane: increases production
Sevo: decreases production

84
Q

What is the best way to preserve evoked potentials

A

TIVA

85
Q

What so volatile anesthetics do to evoked potentials

A

Decrease amplitude
Increase latency

86
Q

What is the max MAC you should use when monitoring evoked potentials?

A

0.5 MAC

87
Q

Match each peripheral nerve with its function?

A

A Alpha: motor
A Delta: fast pain
B: preganglionic SNS
C: slow pain

88
Q

What is the order of blockade in neural fibers

A

1st: B fibers (ANS fibers)
2nd: C fibers (slow pain, temp, touch)
3rd: A-delta fibers (fast pain, touch, temp)
4th: A-alpha (motor, proprioception)

89
Q

Fibers that are more easily blocked have a _______ ____

Fibers that are more resistant to local anesthetics have a ________ ____

A

Lower cm

Higher cm

90
Q

Where and when do local anesthetics bind?

A

Local anesthetics bind to the alpha sub-unit of the sodium channel when it is in the ACTIVE or INACTIVE states

91
Q

What is a use-dependent or physic block?

A

The more frequently a nerve is depolarized and voltage-gated sodium channels open, the more time available for local anesthetic binding to occur and the faster the nerve will be blocked.

Apex (47 decks)

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