inhalational agents - individual agents Flashcards

1
Q

Halothane
- blood:gas
- MAC
- MAC-awake
- MW
- Vapor pressure @ 20 C

A

Halothane
2-bromo-2-chloro-1,1,1-trifluroethane
- blood:gas - 2.4
- MAC - 0.76%
- MAC-awake - 55% of MAC
- MW - 197.4
- Vapor pressure @ 20 C - 244 torr

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2
Q

Halothane: _____, ______ odor

A

sweet, nonpungent

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3
Q

Halothane: stable in ____ ____, but decomposes _____ products and most ______

A

soda lime
rubber
metals

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4
Q

Halothane: requires storage in _____ _____ and preservative ______, to prevent spontaneous oxidative decomposition

A

dark bottle
thymol

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5
Q

Halothane: breaks down to (5)

A
  1. hydrochloric acid
  2. hydrobromic acid
  3. chloride
  4. bromide
  5. phosgene
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6
Q

Halothane cardiac: dose-dependent myocardial _____ ______ causes decreased _____ and decreased _____

A

contractility depression
CO
BP

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7
Q

Halothane cardiac: 2 MAC causes

A

50% reduction in BP, CO

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8
Q

Halothane cardiac: slows conduction through the AV node to cause _______ _______, _____ _____, and _______

A

junctional rhythms, wandering pacemaker, and bradycardia

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9
Q

Halothane cardiac: inhibits ______ _____

A

baroreceptor reflex

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10
Q

Halothane cardiac: sensitizes myocardium to ______

A

catecholamines

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11
Q

with halothane: adults epi max dose _____, and when ______ is added it doubles dose of epi allowed

A

1.5 mcg/kg subq
0.5% lidocaine

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12
Q

with halothane: children epi doses

A

more tolerant - 7.8-10 mcg/kg with and without lido

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13
Q

Halothane: hypercarbia enhances

A

sensitization

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14
Q

Halothane sensitization of heart thought to be due to effect on the _____ _____ of cardiac impulses through the _______ system

A

transmission rate
conduction

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15
Q

Halothane resp: excellent _______ - reverses asthma induced _______

A

bronchodilator
bronchospasms

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16
Q

Halothane resp - may be the best ______ of currently used inhaled agents

A

bronchodilator

but is likely there is no clinical significant difference between agents

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17
Q

Halothane resp: works by inhibiting _____ _____ mobilization - bronchial smooth muscle

A

intracellular calcium

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18
Q

Halothane resp: ________ inhalation induction

A

nonpungent

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19
Q

Halothane CNS: direct cerebral _______, decreases ______

A

vasodilation
CMRO2

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20
Q

Halothane CNS: cerebral autoregulation is _____

A

attenuated (DESTROYED)

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21
Q

Halothane CNS: must _______ ______ to initiation of halothane

A

hyperventilate PRIOR

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22
Q

Halothane CNS: at 1.1 MAC and MAP of 80, halothane increases CBF by _____

A

190% (more than iso)

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23
Q

Halothane: MH ____ ____ trigger

A

most potent

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24
Q

Halothane metabolism: ___-____ metabolized

A

15-40%

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25
Q

Halothane hepatitis: ___ ____ mechanism

A

no clear

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26
Q

Halothane hepatitis: likely an _______ that binds to hepatocytes previously exposed to halothane, has been isolated from _____ of patients with halothane-induced _____ _____

A

antibody
70%
hepatic dysfunction

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27
Q

Halothane hepatitis: this antibody response may involve microsomal proteins that have been modified by ______ _____ as the triggering antigens

A

trifluoroacetic acid

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28
Q

Halothane hepatitis: incidence is __ in _____ fatal, hepatic ____ (1 in 10,000 ____)

A

1 in 35,000
necrosis
jaundice

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29
Q

Halothane hepatitis: hepatitis due to other inhaled agents ___ in ____ _____

A

1 in 1 million

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30
Q

Halothane hepatitis: incidence is higher if halothane exposure _____ within ____ ____

A

repeats within 28 days

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31
Q

Halothane hepatitis: risk factors (5)

A
  • sepsis
  • obesity
  • age > 40 yrs
  • female
  • enhanced metabolism/induced enzymes
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32
Q

Halothane hepatitis: rarely reported with _______ _______ even with pre-existing liver disease

A

pre-pubescent children

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33
Q

Halothane hepatitis: similar hepatitis can be induced with other volatiles but ______

A

rarely

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34
Q

Halothane hematology: like sevo, halothane may cause a _____ in _____ ____ and increases _____ time

A

decrease in platelets
increases bleeding time

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35
Q

Halothane immune: unlike the other three potent agents, halothane depresses the defense against _____, the _____ _____ response of ______

A

infection
oxidative burst response of neutrophils

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36
Q

Isoflurane
- chemical name
- blood:gas
- MAC
- MAC-awake
- MW
- Vapor pressure @ 20 C

A

Isoflurane
- chemical name - 1-chloro-2,2,2-trifuoroethyl-difluoromethyl ether
- blood:gas - 1.4
- MAC - 1.17%
- MAC-awake - 38% of MAC
- MW - 184
- Vapor pressure @ 20 C - 240 torr

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37
Q

Isoflurane: ______, _____-type smell

A

pungent, ether

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38
Q

Isoflurane: isomer of ______

A

enflurane

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39
Q

Isoflurane: stable, ________

A

nonflammable

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40
Q

Isoflurane: no ________ necessary

A

preservative

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41
Q

Isoflurane cardiac: minimal _____ ______; decreased oxygen demand more in ______ than _____ _____

A

myocardial depression
heart
other organs

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42
Q

Isoflurane cardiac: cardiac output preserved by increased _____ related to _______

A

HR
baroreceptors

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43
Q

Isoflurane cardiac: _____ decreases but _____ remains nearly constant due to compensation

A

SV
CO

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44
Q

Isoflurane cardiac: rapid increase in concentration causes increases in ____, _____, and _______

A

HR, BP, and norepinephrine

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45
Q

Isoflurane cardiac: different from other agents due to ____ _____-_____ _____ properties

A

mild beta-adregnergic agonist

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46
Q

Isoflurane cardiac: decreases coronary vascular _______ with coronary blood flow ______ or _______

A

resistance
increased
unchanged

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47
Q

Isoflurane cardiac: unlike nitroglycerin, isoflurane dilates small ______ ______ ______ within the heart muscle

A

endocardial coronary arteries

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48
Q

Isoflurane cardiac: coronary artery steal - the studies suggest that with the steal, the _____ fell significantly; other studies suggest that steal doesnt occur

A

MAP

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49
Q

Isoflurane cardiac: ____ is decreased based on dose; this is mainly due to _____ reduction

A

BP
SVR

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50
Q

Isoflurane: carotid sinus baroreceptor reflex is maintained at _______ but depressed at ______

A

1 MAC
2 MAC

Iso - studies differ - abolish at 1.25 MAC v. some response at 1.5 MAC

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51
Q

Isoflurane: Accessory pathway conduction - increases the ________ of accessory pathways and the _____ _______ system

A

refractoriness
AV conduction

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52
Q

Isoflurane: accessory pathway conduction - interferes with interpretation of confirming success of _____ _____

A

ablation procedures (suppression of SVT re-entry tachycardia)

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53
Q

Isoflurane ablations: prolong action-potential duration, delay _____ and _____ ________, decrease ________ inducibility

A

atrial and vent repolarization
tachyarrythmia

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54
Q

Isoflurane ablations: enhance automaticity of secondary _____ ______ causing ectopic atrial rhythms

A

atrial pacemakers

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55
Q

Isoflurane: ____ prolongation in healthy patients, may not be seen in pts with idiopathic long _____

A

QT
QTc

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56
Q

Isoflurane resp: causes greater resp depression than ______

A

halothane

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57
Q

Isoflurane resp: tachypnea is ____ ____ resulting in enhanced reduction in _____ _____

A

less pronounced
minute ventilation

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58
Q

Isoflurane resp: _____ and _____ to some airways; however, overall good ______

A

pungent and irritating
bronchodilator

not as good as halothane

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59
Q

Isoflurane CNS: at concentrations greater than 1 MAC, iso increases _____ and _____

A

CBF
ICP

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60
Q

Isoflurane CNS: ________ that accompanies the introduction of iso can minimize the effect on ______

A

hyperventilation
ICP

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61
Q

Isoflurane CNS: when iso is used for deliberate hypotension, it ______ _____ _____ ______

A

decreases cerebral oxygen demand

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62
Q

Isoflurane CNS: at 2 MAC, iso results in an _______ ______; this provides _____ protection during episodes of ______ ischemia

A

isoelectric EEG
brain
cerebral

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63
Q

Isoflurane hepatic: hepatic oxygenation is better maintained because……

A

hepatic artery perfusion and hepatic venous oxygen saturation are preserved

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64
Q

Isoflurane hepatic: iso is metabolized to ______ ions, _____, and _____ acid, but there are no real concerns for ______ ______ levels

A

fluoride
TFA
formic
inorganic fluoride levels

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65
Q

Isoflurane hepatic: ICU pt on iso for 30 MAC hours had a max inorganic fluoride level of ______ and _____ ______ of renal failure

A

37 mcgmol/L
no evidence

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66
Q

Isoflurane hepatic: metabolized ___

A

0.2%

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67
Q

Desflurane
- chemical name
- blood:gas
- MAC
- MAC-awake
- MW
- Vapor pressure @ 20 C

A

Desflurane
- chemical name - difluromethyl 1-fluoro 2,2,2-trifluroethyl ether
- blood:gas - 0.42
- MAC - 6.6%
- MAC-awake - 34% of MAC
- MW - 168
- Vapor pressure @ 20 C - 669 torr
- boiling point - 22.8 degrees C

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68
Q

Desflurane: differs from iso only in the substitution of a ______ atom for a _____ atom on the alpha ethyl carbon

A

fluorine
chlorine

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69
Q

Desflurane: ____ boiling point and _____ vapor pressure require _____-controlled vaporizer

A

low
high
temperature

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70
Q

Desflurane: stable in _____ absorbant

A

moist

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71
Q

Desflurane: requires no _______

A

preservatives

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72
Q

Desflurane: odor

A

pungent (the worst!)

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73
Q

Desflurane: bc Des is less potent, there are ranges of MAC values in different age groups -
- 0.6-0.7 years
- 25 years
- 36-49 years
- 65 years

A
  • 0.6-0.7 years - 9.96%
  • 25 years - 7.25%
  • 36-49 years - 6.0%
  • 65 years - 5.17%
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74
Q

Desflurane: blood gas solubility (0.42) very similar to ____ (___)

A

N2O (0.46)

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75
Q

Desflurane: fat:gas solubility of ____ compared to _____ for isoflurane

A

13
70

76
Q

Desflurane cardiac: RAPID increase in the concentration above ____ can cause sympathetic ______ with _______ HR and BP

A

6%
stimulation

77
Q

Desflurane cardiac: can double ___ and ___ with change from ___ to ___ in less than one minute

A

HR and BP
4% to 8%

78
Q

Desflurane cardiac: HR and BP increase is accompanied by a significant increase in _____ _____ suggesting enhanced release from the _____ _____

A

plasma epinephrine
adrenal gland

79
Q

Desflurane cardiac: sympathetic stimulation most commonly seen in ____ _____ patients with little _____

A

young healthy patients
opioids

80
Q

Desflurane cardiac: SNS stimulation occurs both with _____ and without

A

N2O

81
Q

Desflurane cardiac: SNS stimulation returns to normal within ______

A

5 mins

82
Q

Desflurane cardiac: how do we limit change to HR and BP?

_______ _____ PRIOR to increasing concentration

A

fentanyl 1.5 mcg/kg

83
Q

Desflurane cardiac: how do we limit change to HR and BP?

dont exceed ____ _____

A

6% desflurane

84
Q

Desflurane cardiac: how do we limit change to HR and BP?

Increase ______ to minimize change

A

SLOWLY (even above 6%)

85
Q

Desflurane cardiac: how do we limit change to HR and BP?

Drugs we can give (4)

A
  1. alfentanil
  2. sufentanil
  3. clonidine
  4. beta blockers
86
Q

Desflurane cardiac: how do we limit change to HR and BP?

_____ affects increase in HR but doesnt change BP

A

esmolol

87
Q

Desflurane cardiac: how do we limit change to HR and BP?

Lidocaine 1.5 mg/kg minimizes _____ response but not ____ response

A

HR
BP

88
Q

Desflurane cardiac: how do we limit change to HR and BP?

_____ and _____ have no effect

A

propofol and N2O

89
Q

Desflurane cardiac: ____ decreases but to a lesser extent with iso

A

SVR

90
Q

Desflurane cardiac: decreased resistance to _____ ____ ____

A

coronary blood flow

91
Q

Desflurane cardiac: ______ (____ ____) not seen when CAD is present

A

redistribution (coronary steal)

92
Q

Desflurane respiratory: respiratory depression is similar to _____ up to _____

A

isoflurane
1.24 MAC of Des

93
Q

Desflurane respiratory: profound resp depression to apnea at ___-___ ____

A

1.5-2 MAC

94
Q

Desflurane respiratory: HPV is ______ as it is with sevo and iso

A

preserved

95
Q

Desflurane respiratory: less effect on ____ ____ than other agents

A

hypoxic drive

96
Q

Desflurane respiratory: 0.1 MAC of des decreased hypoxic drive response by ____ with _____

A

30% with hypercapnia
(other volatiles 50-70% decrease)

97
Q

Desflurane respiratory: causes _____ resistance with ______

A

increased resistance with smokers
(less than 6% is less irritating, can give fent to help minimize irritation as well)

98
Q

Desflurane neuromuscular: causes fade with tetanus at ____ to ____

A

3% to 12%

99
Q

Desflurane neuromuscular: potentiated _____, ______, ______, and ____ in a dose-dependent manner

A

pancuronium, vecuronium, rocuronium, and succ

100
Q

Desflurane neuromuscular: some studies say des has the greatest effect on ____

A

NMB

101
Q

Desflurane CNS: EEG changes similar with ______

A

isoflurane

102
Q

Desflurane CNS: burst suppression at ______, no _____ activity

A

1.24 MAC
seizure

103
Q

Desflurane CNS: ______ _____ at 1.5 - 2.0 MAC

A

isoelectric EEG

104
Q

Desflurane CNS: cerebral blood flow similar with _____ during 1 and 1.5 MAC

A

isoflurane

105
Q

Desflurane CNS: consider use during deliberate hypotension due to rapid ______ and reduction of ______ and _____

A

titratability
CMRO2
CPP

106
Q

Desflurane CNS: maintains ______ at 1 MAC

A

autoregulation

107
Q

Desflurane metabolism: ____ metabolized at ____

A

least
0.02%

108
Q

Desflurane metabolism: minute amount of ____ produced

A

TFA

109
Q

Desflurane metabolism: no increase in serum ____ ____

A

inorganic fluoride

110
Q

Desflurane metabolism: greenhouse effect (8 hr day using 1-2 L/min FGF)
- Des
- Sevo
- Iso

A
  • Des - 58-116 days worth of auto emission
  • Sevo - 4.3 days
  • Iso - 4.8-9.6 days
111
Q

Sevoflurane
- chemical name
- blood:gas
- MAC
- MAC-awake
- MW
- Vapor pressure @ 20 C

A
  • chemical name - fluoromethyl 2,2,2-trifluoro-1-(trifluoromethyl) ethyl ether
  • blood:gas - 0.69
  • MAC - 1.8%
  • MAC-awake - 34% of MAC
  • MW - 200
  • Vapor pressure @ 20 C - 170 torr
112
Q

Sevoflurane: odor

A

nonpungent, sweet smelling

113
Q

Sevoflurane: ___ solubility
- blood:gas
- fat:gas

A

low
- blood:gas - 0.65 v. des 0.42 v. iso 1.4
- fat:gas - 37 v. des 13 v. iso 70

114
Q

Sevoflurane: is _____ and can spontaneously degrade, must have _____ added as a preservative, bottles changed to _____

A

unstable
water
plastic

115
Q

Sevoflurane: reactive with _____ to produce _____

A

CO2 absorbant
compound A

116
Q

Sevoflurane: potential for ____ with dry absorbant

A

fire

117
Q

Sevoflurane cardiac: myocardial depression is comparable to _______ at _____ MAC concentrations

A

isoflurane
equal

118
Q

Sevoflurane cardiac: _____ decreased at 1/1.5 MAC and recovered at 2 MAC

A

CO

119
Q

Sevoflurane cardiac: increase ____ > 1.5 MAC

A

HR

120
Q

Sevoflurane cardiac: RARELY _______ but treat by ______ concentration

A

bradycardia

121
Q

Sevoflurane cardiac: prolong ____ _____ - use with caution in pts with previously prolonged ____

A

QT interval
QT

122
Q

Sevoflurane cardiac: minimal effect on conduction of ____, ____, and _____ pathway

A

AV, SA, and accessory pathway

123
Q

Sevoflurane cardiac: ______ suppression, prolongs _____ and _____ _____ - may affect arrhythmogenicity

A

autonomic
QT
action potential

124
Q

Sevoflurane cardiac: _____ reduction is slightly less magnitude than iso

A

SVR

125
Q

Sevoflurane cardiac: SVR reduction different mechanism than isoflurane - reduces resistance through aortic arch (arterioles at higher concentrations and abruptly), v. iso that reduces arteriolar resistance ____ and _____-_____

A

gradually and dose-dependently

126
Q

Sevoflurane cardiac: ______ is preserved to a greater extent than with other agents

A

baroreflex

127
Q

Sevoflurane resp: ______, stoelting says it causes the ____ ____ of airway irritation among available agents

A

bronchodilator
least degree

128
Q

Sevoflurane compared to Halothane for inhalation induction: sevo is better for 4 things -

A
  1. slightly faster
  2. less patient movement
  3. quicker onset of mobility
  4. fewer airway problems

of course - other studies contradict

129
Q

Sevoflurane: at ______ concentrations sevo causes less myocardial depression than halothane

A

HIGH

130
Q

Sevoflurane inhalation induction: adult, healthy, unpremedicated, given vital capacity breaths of up to 7% sevoflurane (3)

A
  1. loss of lash reflex in 1 min
  2. acceptance of LMA in 1.7 mins
  3. laryngoscopy, intubation in 4.7 mins
131
Q

Sevoflurane HPV: ______ at clinically used concentrations

A

preserved

132
Q

Sevoflurane neuromuscular: enhanced _____ and _____ of NMB, may prolong duration of _______ slightly longer than iso

A

intensity and duration
rocuronium

133
Q

Sevoflurane CNS: _______ preserved up to 1.5 MAC

A

autoregulation

134
Q

Sevoflurane CNS: _____ _____ similar to that with iso

A

cerebral vasodilation

135
Q

Sevoflurane CNS: EEG may have evidence of _____ _____ (__%)

A

seizure activity (7%)

136
Q

Sevoflurane: _____ ______ inhibited more strongly than halothane due to suppression of ______ acid, probably due to inhibition of ______

A

platelet aggregation
arachadonic
cyclooxygenase

137
Q

Sevoflurane metabolism: 5-8% of sevo is metabolized by ______ to produce _____ _____

A

CYP450
inorganic fluoride

138
Q

Sevoflurane metabolism: levels of serum fluoride greater than 50 mcmol/L in 7% of patients; BUT….

A

no evidence of clinically significant renal dysfunction

139
Q

Nitrous oxide
- blood:gas
- MAC
- MAC-awake
- MW
- Vapor pressure @ 20 C
- critical temp

A
  • blood:gas - 0.46
  • MAC - 104%
  • MAC-awake - 64% of MAC
  • MW - 44
  • Vapor pressure @ 20 C - gas form
  • critical temp - 35.5 degrees C
140
Q

Nitrous oxide: organic or inorganic?

A

inorganic

141
Q

Nitrous oxide: ____ molecular weight

A

low

142
Q

Nitrous oxide: odor

A

odorless (sweet smelling)

143
Q

Nitrous oxide: ____ solubility, equilibrates _____

A

low
rapidly

144
Q

Nitrous oxide: ____ potency

A

low

145
Q

Nitrous oxide: non______ but supports _____

A

nonflammable
combustion

146
Q

Nitrous oxide: stored in a ____-____ equilibrium @ ____ psi in blue cylinders

A

liquid-gas
745 psi

147
Q

Nitrous oxide: stable with ____ ____

A

soda lime

148
Q

Nitrous oxide: 4 impurities in Nitrous oxide

A
  1. N2
  2. NO
  3. NO2
  4. water vapor
149
Q

Nitrous oxide: does not combine with _____, carried in solution in _____

A

Hgb
blood

150
Q

Nitrous oxide: hepatic enzymes are _____ by N2O

A

induced

151
Q

Nitrous oxide: less than _____ is metabolized by ____ ____

A

0.004%
intestinal flora

152
Q

Nitrous oxide cardiac: ____ ____ on myocardial depression

A

direct effect

153
Q

Nitrous oxide cardiac: young and healthy -

A

SNS stimulation and increased SVR due to increased endogenous catecholamines

154
Q

Nitrous oxide cardiac - increased ____ (esp if already slightly elevated)

A

SVR

(dont want to use with congenital heart kids)

155
Q

Nitrous oxide cardiac: with pre-existing CVD, myocardial depression can be significant, ____% produces myocardial depression and adds to _____ ______

A

40%
opioid anesthetic

156
Q

Nitrous oxide respiratory: at concentrations < 50% no increase in PaCO2; it increases ____ more than other agents

A

RR

157
Q

Nitrous oxide respiratory: response to _____ is reduced with even small amounts of N2O

A

hypoxia

158
Q

Nitrous oxide neuromuscular: does NOT potentiate _______ ______, but DOES potentiate ______, and increases muscle rigidity with _____

A

nondepolarizing NMB
succinylcholine
opioids

159
Q

Nitrous oxide CNS: produces ____ and ____

A

analgesia and amnesia

160
Q

Nitrous oxide CNS: analgesia due to increase in ______ _____

A

enkephalins produced

161
Q

Nitrous oxide CNS: ______ occurs with 50% N2O

A

nystagmus

162
Q

Nitrous oxide CNS: EEG effects similar to volatiles - _____ ____ and _____ _____

A

slowing frequency and higher voltage

163
Q

Nitrous oxide CNS: cerebral vasodilation ____ than potent agents

A

less

164
Q

Nitrous oxide CNS: increases _____

A

CMRO2

165
Q

Nitrous oxide CNS: ____ ____ seen with nitrous may reflect acute nitrous dependence

A

withdrawal seizures

166
Q

Nitrous oxide CNS: neuropathy/sensorimotor polyneuropathy - related to _____ effect on _____ atom of ______ ______

A

oxidizing effect
cobalt atom
vitamin B12

167
Q

Nitrous oxide GI: gas in the bowel will…

A

increase in size with the use of nitrous

168
Q

Nitrous oxide GI: increased incidences of _____ - controversial yet meta analysis of studies show increased incidence of ______

A

PONV
PONV

169
Q

Nitrous oxide uterine/reproductive: ____ _____ effect uterine tone

A

does not effect

170
Q

Nitrous oxide uterine: weak ____ when used in high concentrations for prolonged time frame

A

teratogen

171
Q

IMPORTANT
Nitrous oxide Vit B12 dependent enzymes: inhibits ____ ____ which is necessary for _____ formation, and _____ ____ which is necessary for _____ _____

A

methionine synthetase
myelin formation
thymidylate synthesis
DNA synthesis

172
Q

Nitrous oxide Vit B12 dependent enzymes: prolonged exposure can result in ____ _____ depression - ______ anemia, and even ______ deficiencies - peripheral neuropathies and pernicious anemia

A

bone marrow depression - megaloblastic anemia
neurological

173
Q

Nitrous oxide: ENIGMA and ENIGMA II showed nitrous free anesthesia had decreased ____, _____ _____, _____, _______, _______

A

decreased PONV, wound infection, fever, pneumonia, atelectasis

174
Q

Nitrous oxide: 59% increase in long term risk of ____; increased _____ levels

A

MI
homocysteine

(postop strokes/deaths NOT increased)

175
Q

Nitrous oxide diffusion: ____ more soluble than _____ in the blood

A

34x
nitrogen

176
Q

Nitrous oxide diffusion: it is absorbed into air-filled spaces faster than nitrogen moves back into blood causing _____ of _____

A

expansion of bubble

177
Q

Nitrous oxide diffusion: air expansion can affect…

A
  • ears
  • pneumo
  • gastric/intestinal air
  • retinal detachment
  • intraocular gas bubble that serves as tamponade or splint
178
Q

Nitrous oxide immunologic: affects chemotaxis and mobility of _______ ______ for ______ which is necessary for the inflammatory response to infection

A

polymorphonuclear leukocytes for phagocytosis

179
Q

Nitrous oxide: diffusion hypoxia - N2O is so insoluble that it returns to alveoli so rapidly and in such volumes that it….

A

dilutes other gases including oxygen

(this can be avoided by supplemental O2 for 5-10 mins after its dc’d)

180
Q

Nitrous oxide: second gas effect - administering high concentrations of N2O will cause an increase of the _____ ______ of a _____ gas

A

alveolar concentration
second gas

(theoretically)

181
Q

Nitrous oxide: when N2O is utilized, the ____ concentration must be _____

A

oxygen
decreased

182
Q

Nitrous oxide: care must be taken to avoid hypoxia especially in special populations such as…

A

c-section - common practice to deliver more than 50% N2O prior to delivery of infant (however with emergency cases youre worried about baby being deprived of O2)

183
Q

Nitrous oxide: occupational risks - recent studies showed with scavenging and limited exposure….

A

it failed to show difference in fertility and birth defects with gen pop

184
Q

Nitrous oxide: if substituted for a portion of a volatile agent, it (3)

A
  1. decreases magnitude of BP decrease
  2. less depression of ventilation (doesnt increase PaCO2)
  3. MAC portion r/t N2O is not reduced due to decrease in temp
185
Q

in summary:

A