Inhalation Agents--Pharm Test 3

Front 1

What's the generic name for Penthrane?

Back 1

Methoxyflurane

Front 2

What's the generic name for Halothane?

Back 2

Fluathane

Front 3

What's the generic name for Ethrane?

Back 3

Enflurane

Front 4

What's the generic name for Forane?

Back 4

Isoflurane

Front 5

What's the generic name for Suprane?

Back 5

Desflurane

Front 6

What's the generic name for Ultane?

Back 6

Sevoflurane

Front 7

What's the chemical name for Nitrous Oxide?

Back 7

N2O

Front 8

What's the trade name for Methoxyflurane?

Back 8

Penthrane

Front 9

What's the trade name for Fluathane?

Back 9

Halothane

Front 10

What's the trade name for Enflurane?

Back 10

Ethrane

Front 11

What's the trade name for Isoflurane?

Back 11

Forane

Front 12

What's the trade name for Desflurane?

Back 12

Suprane

Front 13

What's the trade name for Sevoflurane?

Back 13

Ultane

Front 14

What does N2O stand for?

Back 14

Nitrous Oxide

Front 15

which 2 inhalation agents are not used in the U.S. anymore but are used in other countries due to how cheap they are?

Back 15

Halothane (Fluathane) and Ethrane (Enflurane)

Front 16

Which inhalation agent is not used ANYWHERE anymore?

Back 16

Penthrane (Methoxyflurane)

Front 17

Which inhalation agent is non-pourable?

Back 17

Suprane (Desflurane)

Front 18

Why is Suprane (Desflurane) non-pourable?

Back 18

it evaporates too quickly; it must be used in a closed system

Front 19

What is considered to be the "Gold Standard" for inhalation agents?

Back 19

Response to surgical skin incision

Front 20

Who and in what year made the 1st attempts to describe anesthetic depth and potency?

Back 20

John Snow, Plomley in 1847

Front 21

What are 7 specific signs of CNS Depression that were assessed in 1847 to describe the anesthetic depth and potency?

Back 21

Movement in response to surgical stimuli, Loss of righting reflex, EKG suppression (bradycardia, tachycardia, etc), Diameter of Pupils, Eye movement, Respiration patterns and Muscle tone

Front 22

In 1963, only one parameter was distinguished in describing anesthetic depth and potency. What was it?

Back 22

Abolition of movement in response to noxious stimuli

Front 23

What is the general definition of MAC?

Back 23

Minimal Alveolar Concentration of anesthetic at 1 atm required to abolish movement in 50% of pts (or animals) in response to noxious stimuli

Front 24

Can you measure MAC immediately after the first couple of breaths? Why or why not?

Back 24

NO; takes some time over several breaths for partial pressures to equalize

Front 25

Are inspired and alveolar partial pressures equivalent or different?

Back 25

Equivalent

Front 26

Are Alveolar and Brain partial pressures the same or different at equilibrium?

Back 26

The Same

Front 27

Does the anesthetic partial pressure change when at sea level versus on top of Mt. Everest?

Back 27

No, it stays the same

Front 28

MAC represents anesthetic activity at the _________.

Back 28

Site of Action

Front 29

Is MAC applied to all inhaled agents?

Back 29

YES

Front 30

What is an indicator of anesthetic depth that is unlike clinical signs which rely on side effects and varies from one drug to another?

Back 30

MAC

Front 31

In relation to MAC, what is considered the "noxious stimuli" used in humans?

Back 31

Surgical Skin Incision

Front 32

In relation to Mac, what is considered the "noxious stimuli" used in animals?

Back 32

Either a tail clamp or S.Q. electrical current

Front 33

MAC concentrations produce equivalent ________; however, MAC may produce different effects on ________, ________, and ________.

Back 33

equivalent depression of CNS; different effects on ventilation, BP and CO

Front 34

1 MAC of Enflurane depresses CO (greater than/less than/equal to) 1 MAC of Isoflurane?

Back 34

Greater Than

Front 35

Describe how MAC values are ADDITIVE (give an example)

Back 35

0.5 MAC N2O + 0.5 MAC Isoflurane has the same effect on the CNS as 1 MAC of either agent alone

Front 36

We don't usually combine more than 1 Volatile Inhalation agent; What is the only inhalation agent we can combine with the other volatile inhalation agents?

Back 36

Nitrous Oxide (N2O)

Front 37

Why can't we use Nitrous Oxide (N2O) as a sole inhalation agent at 1 atm?

Back 37

Nitrous Oxide has a MAC of 104%; if given alone, it will not allow for an adequate level of O2; pt will not receive enough O2

Front 38

what MAC prevents movement in 95% of patients?

Back 38

1.3 MAC

Front 39

Whatis the MAC of N2O (Nitrous Oxide) (in O2)?

Back 39

104%

Front 40

What's the MAC of Methoxyflurane (Penthrane) in O2?

Back 40

0.16%

Front 41

What's the MAC of Halothane (Fluathane) in O2?

Back 41

0.75%

Front 42

What's the MAC of Enflurane (Ethrane) in O2?

Back 42

1.63%

Front 43

What's the MAC of Isoflurane (Forane) in O2?

Back 43

1.17% (up to 1.2%)

Front 44

What's the MAC of Desflurane (Suprane) in O2?

Back 44

6.6%

Front 45

What's the MAC of Sevoflurane (Ultane) in O2?

Back 45

1.8% (up to 2.05%)

Front 46

How do we administer the appropriate MAC percentage of each inhalation agent?

Back 46

Given via vaporizers; use the control dial to adjust percentage settings

Front 47

MAC is age dependent; it is _____ in newborn and ______ in elderly

Back 47

Highest in newborn; lowest in elderly

Front 48

MAC is body temperature dependent; MAC _____ with decreased temperature and ______ with increased temperature

Back 48

Decreases with decreased temperature and increases with increased temperature

Front 49

MAC decreases about __-__% per degree decrease in body temperature

Back 49

2-5%

Front 50

What are 5 major factors that INCREASE MAC?

Back 50

Hyperthermia, Hyperthyroidism, Alcoholism (chronic), Acute administration of dextroamphetamine, young age

Front 51

Acute administration of Dextroamphetamines increase MAC; What are 4 examples of Dextroamphetamines?

Back 51

MAO inhibitors, Cocaine, Ephedrine and Levodopa

Front 52

What are 6 MAJOR factors that DECREASE MAC?

Back 52

Hypothermia, Severe Hypotension, Advanced Age, Admin. of Opioids and/or Ketamine, Chronic admin. of Amphetamine, Admin. of Reserpine and/or alpha-methyldopa

Front 53

What are non-major factors that DECREASE MAC?

Back 53

Cholinesterase inhibitors, IV local anesthetics, Pregnancy, Hypoxemia (PaO2< 40 mmHg), anemia, and admin. of alpha-2 agonists

Front 54

What are 6 factors that DO NOT effect MAC?

Back 54

Duration of anesthesia, Sex, Metabolic Acid-Base status, Hypercapnia and hypocapnia, Isovolemic Anemia, and HTN

Front 55

Oil:Gas Partition Coefficient is a basic measurement of an inhaled agent's ________.

Back 55

Lipid Solubility

Front 56

An agent with a Oil:Gas Partition Coefficient of 100 means what?

Back 56

100x more of this agent is attracted to oil than gas

Front 57

What's the estimation measurement (mathematical formula) of an agent's MAC in regards to the Oil:Gas Partition Coefficient?

Back 57

150/oil:gas p.c. of I.A.

Front 58

What would the MAC be of an agent with an oil:gas partition coefficient of 100?

Back 58

150/100=1.5%

Front 59

What are the general pharmacokinetics of inhaled anesthetics?

Back 59

Absorption (uptake of IA from Alveoli into Pulmonary Capillary Blood), distribution in the body and elimination via the Lungs and/or liver & kidneys

Front 60

Take home message regarding Oil:Gas Partition Coefficient and MAC: The more lipid soluble the inhaled anesthetic agent is, the _____ the MAC would be

Back 60

LOWER

Front 61

What is the MAJOR objective of Inhalation Anesthesia? This is also the definition of "General Anesthesia"

Back 61

To cause a state in which body is insensible to pain and other stimuli

Front 62

How is General Anesthesia achieved?

Back 62

By obtaining a constant and optimal CNS partial pressure of the Inhaled Anesthetic

Front 63

True/False: The Brain, Spinal Cord and all other tissues equilibrate with the partial pressure of anesthesia agent in the blood

Back 63

TRUE;
PA = Pa = PCNS

Front 64

True/False: When the partial pressure of anesthesia agent in blood equilibrates with the brain, spinal cord, and all other tissues, this means that the concentration is also the same in both places

Back 64

FALSE; partial pressures equilibrate but this does NOT mean the concentrations become the same

Front 65

Are gases (or vapors) simple molecules or complex?

Back 65

Simple Molecules

Front 66

Are gases (or vapors) confined or do they move freely?

Back 66

Move Freely

Front 67

Direction of movement of gases (or vapors) is determined by the ____ ____ (from high to low pressure)

Back 67

Pressure Gradient

Front 68

Gases move from areas of ____ pressure to areas of ____ pressure

Back 68

High to Low Pressure

Front 69

One aspect of Dalton's Law of Partial Pressure: Sum of partial pressure = _______.

Back 69

Pressure exerted by the mixture

Front 70

True/False regarding Dalton's Law: In a mixture of gases (or vapors) the pressure exerted by each gas is the same as it would exert if it occupied the container alone

Back 70

TRUE

Front 71

True/False: According to Dalton's Law, the pressure each gas exerts is dependent upon other gases present

Back 71

FALSE; each gas exerts its pressure INDEPENDENT of other gases present

Front 72

What is the partial pressure of dry air at atmospheric pressure (1 atm)?

Back 72

760 mmHg

Front 73

What percentage of Nitrogen is present in dry air? Does this percentage change whether at sea level or on Mt. Everest?

Back 73

79% Nitrogen in dry air; percentage does NOT change; it stays constant

Front 74

What is the percentage of O2 present in dry air? Does this % change whether at sea level or on Mt. Everest?

Back 74

21% Oxygen in dry air; % does NOT change; stays constant

Front 75

What's the partial pressure of Nitrogen in dry air at atmospheric pressure (1 atm)? How is this calculated?

Back 75

600 mmHg; 760 mmHg x 0.79 = 600 mmHg

Front 76

What's the partial pressure of Oxygen in dry air at atmospheric pressure (1 atm)? How is this calculated?

Back 76

160 mmHg; 760 mmHg x 0.21= 160 mmHg

Front 77

Because the partial pressure of dry air on Mt. Everest (220s mmHg) differs from 760 mmHg (at sea level), what is the partial pressure of Oxygen on Mt. Everest and how is this calculated?

Back 77

47 mmHg; 222 mmHg x 0.21 = 47 mmHg

Front 78

When calculating partial pressures of inhalation agents as a % of 1 atm (760 mmHg), what is the partial pressure of a 1% inhaled anesthetic agent; how is this calculated?

Back 78

7.6 mmHg; 760 x 0.01 = 7.6 mmHg

Front 79

When calculating partial pressures of inhalation agents as a % of 1 atm (760 mmHg), what is the partial pressure of a 10% inhaled anesthetic agent; how is this calculated?

Back 79

76 mmHg; 760 x 0.10 = 76 mmHg

Front 80

True/False regarding Vapor Pressure: Molecules escape from the surface of a liquid to enter the space above; Equilibrium is established between the molecules in the vapor phase and the molecules in the liquid phase

Back 80

TRUE

Front 81

What are 3 facts regarding molecules in the Vapor Phase?

Back 81

Molecules in the Vapor phase are in constant motion, molecules strike the walls of the container to exert a Vapor Pressure, and an increase in temperature causes an increase in vapor pressure

Front 82

When the gas phase above the liquid holds all the vapor that it can hold at that temperature, it is said to be _____.

Back 82

Saturated

Front 83

What are 2 factors that the vapor pressure of a potent volatile agent depends on?

Back 83

Depends on the volatile agent itself and the ambient temperature

Front 84

What is the Vapor Pressure of Halothane (Fluathane) at room temp (20 degrees Celsius)?

Back 84

244 mmHg

Front 85

What is the Vapor Pressure of Ethrane (Enflurane) at room temp?

Back 85

172 mmHg

Front 86

What is the Vapor Pressure of Forane (Isoflurane) at room temp?

Back 86

242 mmHg

Front 87

What is the Vapor Pressure of Suprane (Desflurane) at room temp?

Back 87

669 mmHg

Front 88

What is the Vapor Pressure of Ultane (Sevoflurane) at room temp?

Back 88

170 mmHg

Front 89

What's the Vapor Pressure of N2O (Nitrous Oxide) at room temp?

Back 89

Gas

Front 90

What MAC range is considered a lethal dose range of inhalation agents?

Back 90

2-3 MAC

Front 91

Which 2 IAs have Vapor Pressures very similar (in the 170 mmHg range)?

Back 91

Ethrane (172 mmHg) and Ultane (170 mmHg)

Front 92

Which 2 IAs have Vapor Pressures very similar (in the 240 mmHg range)?

Back 92

Halothane (244 mmHg) and Forane (242 mmHg)

Front 93

The temperature at which the Vapor Pressure becomes equal to atmospheric pressure is called the liquid's ____ ____.

Back 93

Boiling Point

Front 94

At what point does all the liquid agent change to the Vapor Phase?

Back 94

Boiling Point

Front 95

What is considered "input" of IAs?

Back 95

Vaporizer to patient breathing circuit

Front 96

What are the 4 general components to "input?"

Back 96

Vaporizer to anesthesia machine inflow, Vapor mixes with carrier gas, Vapor/carrier gas exits anesthesia machine (via common gas outlet), Vapor continues on to patient breathing circuit

Front 97

What are the 3 carrier gases used in anesthesia?

Back 97

O2, N2O, and Air

Front 98

What carrier gas is most often used in anesthesia?

Back 98

O2

Front 99

What is important to consider when using air as a carrier gas?

Back 99

have to mix with O2 to get O2% up to 30%--the minimum amount we use in anesthesia

Front 100

If you're giving an IA with 2L O2 and 1L N2O, how much O2 is being delivered; how is this calculated?

Back 100

33% O2 is being delivered; 100%/3 (2L+1L)=33%

Front 101

What are the 2 types of anesthesia breathing circuits?

Back 101

Rebreathing and Non-rebreathing

Front 102

Which type of breathing system (Rebreathing or non-rebreathing) uses a lower flow rate (<minute volume)?

Back 102

Rebreathing

Front 103

Which type of breathing system (rebreathing or non-rebreathing) uses a low gas flow (<5L/min)?

Back 103

Rebreathing

Front 104

Which type of breathing system (rebreathing or non-rebreathing) has a concentration in inspired gases that differs from inflow concentration?

Back 104

Rebreathing

Front 105

Which type of breathing system (rebreathing or non-rebreathing) uses a high flow rate (5-10 L/min)?

Back 105

Non-Rebreathing

Front 106

With the rebreathing system, why does the concentration in inspired gases differ from the inflow concentration?

Back 106

because exhaled gases have been in the body and they have some anesthetic agent removed from them; dilutional effect of rebreathed gases

Front 107

Which type of breathing system (rebreathing or non-rebreathing) has a concentration in the inflow that is equal to inspired gases?

Back 107

Non-rebreathing

Front 108

Unlike the Rebreathing System, why is the concentration in the inflow equal to inspired gases in the Non-rebreathing system?

Back 108

Only breathing in fresh gases

Front 109

Geographically, on the anesthesia machine, what is considered the "breathing circuit?"

Back 109

from the Common Gas Outlet on

Front 110

How much volume does the anesthesia breathing circuit hold?

Back 110

8-10 liters

Front 111

What type of material are anesthesia breathing circuits composed of?

Back 111

rubber or plastic

Front 112

What are 4 substances Inhaled Anesthetics are soluble in?

Back 112

Rubber, plastic, metal (to a lesser degree) and CO2 absorbent

Front 113

What is the significance of IAs being soluble in Rubber or plastic (what breathing circuits are composed of)?

Back 113

Rubber and Plastic become a reservoir for inhalation agents

Front 114

IA moving from Alveoli to arterial blood to tissue is a function of ______.

Back 114

Uptake

Front 115

Dissolved gases also exert a pressure. What are 3 factors that determine amount of IA dissolved?

Back 115

Partial Pressure of gas, Solubility Coefficient of gas, and Temperature

Front 116

What is Henry's Law?

Back 116

Concentration of dissolved gas = partial pressure times solubility coefficient (pp x sc)

Front 117

True/False: Some types of molecules are physically attracted to H2O while others are repelled

Back 117

True

Front 118

True/False: Hyperthermia decreases MAC

Back 118

FALSE; Hyperthermia increases MAC

Front 119

True/False: Hypothermia decreases MAC

Back 119

TRUE

Front 120

How much more soluble is CO2 than O2?

Back 120

20x

Front 121

What's the solubility coefficient of O2?

Back 121

0.024 (not a starred item to memorize)

Front 122

What's the solubility coefficient of CO2?

Back 122

0.57 (not a starred item to memorize)

Front 123

What's the solubility coefficient of N?

Back 123

0.012 (not a starred item to memorize)

Front 124

The higher the partial pressure, the higher the solubility coefficient and the higher the temperature, the _____ the amount of gas that's dissolved in a liquid.

Back 124

Higher

Front 125

What is the Solubility Coefficient of Desflurane (Suprane)?

Back 125

0.42

Front 126

What is the solubility coefficient of Nitrous Oxide (N2O)?

Back 126

0.46

Front 127

What is the solubility coefficent of Sevoflurane (Ultane)?

Back 127

0.69

Front 128

What is the solubility coefficient of Isoflurane (Forane)?

Back 128

1.46

Front 129

What is the solubility coefficient of Enflurane (Ethrane)?

Back 129

1.9

Front 130

What is the solubility coefficient of Halothane (Fluathane)?

Back 130

2.54

Front 131

What is the solubility coefficient of Methoxyflurane (Penthrane)?

Back 131

12

Front 132

Based on Solubility coefficients, which 3 IAs are relatively insoluble?

Back 132

Desflurane (Suprane), Nitrous Oxide (N2O), and Sevoflurane (Ultane)

Front 133

Based on solubility coefficients, which 3 IAs are moderately soluble?

Back 133

Isoflurane (Forane), Enflurane (Ethrane) and Halothane (Fluathane)

Front 134

Based on solubility coefficients, which IA is the most soluble?

Back 134

Methoxyflurane (Penthrane)

Front 135

What's the range of partition coefficients of the Brain-Blood for IAs?

Back 135

1-2

Front 136

What's the range of partition coefficients of the Muscle-Blood for IAs (with the exception of Nitrous Oxide)?

Back 136

2-3.5

Front 137

What's the range of partition coefficients of the Fat-Blood for IAs (with the exception of Nitrous Oxide)?

Back 137

27-51

Front 138

What's the partition coefficient of Muscle-Blood for Nitrous Oxide?

Back 138

1.2

Front 139

What's the partition coefficient of Fat-Blood for Nitrous Oxide?

Back 139

2.3

Front 140

What % of Desflurane (Suprane) is biodegraded in humans?

Back 140

0-0.02%

Front 141

What % of Isoflurane (Forane) is biodegraded in humans?

Back 141

0-0.2%

Front 142

What % of Sevoflurane (Ultane) is biodegraded in humans?

Back 142

5-8%

Front 143

What's the approximate time constant range for the VRG (in minutes)?

Back 143

4-6 minutes

Front 144

What's the approximate time constant range for the MG (in minutes)?

Back 144

35-59 minutes

Front 145

Approximately how much anesthetic does the 4th compartment (intertissue) hold?

Back 145

30% or 1/3

Front 146

What is the approximate time constant of the 4th compartment (intertissue) in minutes?

Back 146

300-500 minutes