Brainscape's Knowledge GenomeTM

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


See full index

Pharmacology 2 > 5.6 General Anesthetics > Flashcards

5.6 General Anesthetics Flashcards

1
Q

Anesthesia

A

partial or complete loss of all sensation w/ or w/o loss of consciousness

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

General anestesia

A

reversible loss of all sensation and consciousness

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

anestesia is a reversible condition of

A

comfort, quiescence and physiological stability in a patient before, during, and after performance of a procedure (usually surgical)

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

General anesthesia

A

for surgical procedure to render the pt unaware/unresponsive to the painful stimuli

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

GA is characterized by

A

loss of conciousness, analgesia, amnesia, skeletal muscle relaxation, inhibition of autonomic and sensory reflexes

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

analgesia

A

perception of pain eliminated

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

hypnosis

A

unconsciousness

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

essential components of GA

A

analgesia, hypnosis, depression of spinal motor refexes, muscle relaxation –> these terms together emphasize the role of insensibility and of immobility

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

Surgery before anesthesia

A

soprifics, Narcotics, marijuana, belladonna and jimson weed, induction of psychological state of anesthesia by mesmerism or hypnosis

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

Surgical stress

A

evokes HPA axis and sympathetic system

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

Tissue damage during surgery induces

A

coagulation factors and activates platelets leading to hypercoagulability of blood

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

Anesthesia decreases

A

the components of surgical stress response

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

hallmark of anesthesia

A

analgesia, amnesia, muscle relaxation

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

anestheisa is associated with

A

dec in systemic BP (due to myocardial depression and direct vasodialation), blunting of baroreceptor control and decreased central sympathetic tone, muscle relaxation (valuable during anesthesia –facilitates endotrachal intubation)

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

Pre-anesthetic medication

A

use of drugs prior to anesthesia to make it safer and more pleasant, aim is to relieve apprehension and facilitate smooth induction, to supplement analgesic, amnesic aciton of anesthetics, used of preanestetic can decrease requirment of general anesthetic

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

Preanestetics

A

benzos, antihitaminics, antiemetics, opiods, atropine

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

benzo

A

relive anxiety

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

antiheistameinics

A

prevent allergic reactiosn

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

antiemetics

A

prevent nausea and vomiting (antipeptic ulcer drugs can also be given)

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

opiods

A

provide analgesia

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

atropine/anticholinergics

A

prevent bradycardia and secretion

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

balanced anesthesia

A

no single drug achieves all of the desired goals of anesthesia, refers to a combination of drugs used to take advantage of individual drug properties while attempting to minimize their adverse effects, effects are additive, improves potency and provides rapid recovery

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

other drugs can be administered

A

pre, intra, or post operatively to achieve balanced anesthesia, to ensure smooth induction, analgesia, sedation, and smooth recovery. Cater to the individual drug need of the situation.

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

Stages of anesthesia

A

4

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

stage 1

A

analgesia

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

stage 2

A

excitement, combative behavir-dangerous state

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

stage 3

A

surgical anesthesia – further classified into 4 different substages

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

stage 4

A

medullary paralysis – respiratory and vasomotor control seases

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

General anesthetics unique drugs

A

not usually used for therapeutic or preventive, or diagnostic purposes

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

Molecular mechanisms of GA

A

Gaba-A rec Cl channes, glycine receptors

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

GabaA action of GA

A

facilitate Gaba mediated inhibition at Gaba-Arec sites

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

GabaA acting drugs

A

halothane, propofol, etomidate

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

glycine receptor action

A

activity increased, inhaled anesthetics

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

NMDA rec actions

A

inhibited by Ketamine, N2O

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

Mechanisms of Gas

A

depress synamptic transmission, potentiate, block cation channel, receoptor operated ion channels primary site of action

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

potentiation of gaba action

A

pzds, barbiturate, propofol

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

inhibit NMDA rec

A

Ketamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

induction

A

period of time from the onset of administration of the anesthetic to the development of effetive surgical anesthesia, induction of anesthetisa depends on how fast effective concentration of the anesthetic drugs reach the brain, maybe req for breif period then start maintanance drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

maintainces

A

provides sustained surgical anesthesia, after pt is unconcious

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

recovery

A

time from discontinuation of administration of anesthesia until consciousness and protective physiologic reflexes are regained, recovery is the revers of induction and epends on how fast the anesthetic drug diffuses back from the brain, must restore muscle fn before removing endotrachal tube so ask pt to do things so you know pts voluntary muscls are functioning

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

two types of anesthetics

A

intravenous - for induction, inhalational - for mainenance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

if procedure is short

A

induction drug can be used without a maintainance drug

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

intravenous inducing agents

A

thiopental, methohexital, propofol, etomidate, ketamine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

ketamine

A

can be used for a brief surgical procedure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

inhalational gas

A

nitrous oxide (N2O) – cant be used alone so use it with something – need to give O2 when you’re giving anesthesia!!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

inhalational vaporized liquid

A

halothane, enflurane, isoflurane, desflurane, sevoflurane, ether

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

slower acting durgs as adjunct

A

benzos and opioids

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

benzo andjunct

A

diazepam, lorazepam, midazolam

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

opiods

A

fentanyl

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

IV anesthetics uased for

A

rapid induction of anesthesia, produce loss of conciousness in one arm-brain ciruculation time (10 to 20s), high lipophilicity, rapid onset of action, reduce the amount of inhalation anesthetic required for maintenance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

recovery from IV anesthetics

A

maily by redistribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Thiopental action

A

ultra short acting barb, having high libid solubility, also rapid recovery due to rapid redustribution

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

Thiopental time

A

produces unconsiousnes in approx 20 secons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

Thiopental recovery

A

consciousness regained withing 10-20 min by redistribution to skeletal muslce/adipose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

Thiopental effects

A

smooth, pleasant, rapid induction and minimal postoperative nausea and vomiting, eliminated slowly from the body and produce hangover (should not be left on his own –bc even after redistribution some amt of the drug enters the brain and dulls his mind)

56
Q

thipental properties

A

not an analgesic and also a weak muscle relaxant, decreases cerebral blood flow, thus no increase in ICT–> can be used in head injury

57
Q

thiopental adverse effects

A

laryngospasm can occur – atropine may be useful

58
Q

Thipental and CVS

A

produces severe hypotension in hypovolemic pts, dose not sensitize the heart to catecholamines and hence arrhythmia is rare

59
Q

Thiopental complication

A

can percipitate acute intermittent or veriegate porphyria insusceptible individuals –hence contraindicated

60
Q

other uses of thipental

A

rapidly control the seizures since gaba facilitatory and also mimetic

61
Q

Methoxital poency

A

3x more potent than thiopental, quicker and shorter action than thiopental, excitemtn and restlessness during indcution, pain on injection (like propofol)

62
Q

most common IV anesthtic

A

Propofol

63
Q

Propofol

A

most common IV anesthetic (milk of amnesia) , replaced thiopental as the first choice for anesthesia induction and sedation bc it procduces euphoric feeling (subjectivley “feel better”) in the pt and does not cause post anesthetic nausea and vomiting, dec intracranial pressure

64
Q

propofol timeing

A

unconcsiousness in 45 s and lasts 15minutes

65
Q

Propofol can cause

A

pain on injection, dose dependent dec in BP and resp depression, baradycardia, (frequent), excitatory effects (muscle twitiching, spontaneous movements, hiccups) noted in a few pts

66
Q

Propofol benefits

A

is an antiemetic so no postoperative nasea and vomiting, used for sedation in intensive care untis, also suited for day care surgery bc residual imparmetn is less marked (not like thiopental with hangover effect)

67
Q

Ethomidate

A

induction anesthetic, lacks analgesic effect, rapid onset and short duration of action (5-10 min) (briefer than thiopental

68
Q

Ethomidate advantage

A

little CVS and resp depression, used for induction of anesthesia in pts with coronary artery disease or cardiovascular dysfn such as shock

69
Q

what is more common with Ethomidate

A

restless rigidity

70
Q

Why should repeated injections of Etomidate be avoided

A

it suppresses the production of steroids form th eadrenal gland

71
Q

adverse effects of Etomidate

A

postoperative nasea and vomiting, also causes unpredictable and often sever myoclonus during induction

72
Q

Ketamine

A

a short-acting, non barbituarate anesthetic

73
Q

Ketamine induces

A

dissociative anesthsia by blocking NMDA receptors —an effect which pts feel dissociated form their surrouding; also produces analgesia and amnesia, with or without loss of consciousness

74
Q

Inhalational anesthetics

A

are gases or vapors that diffuse rapidly across pulmonary alveoli and tissue barriers

75
Q

advantages of Inhalational anesthetis

A

control the depth of anesthesia

76
Q

Inhalational metabolism and excretion

A

metabolism is very minimal and is excreted by exhalation – what goes incomes out

77
Q

Inhalation anesthetics

A

depth of anesthesia depends upon concnetration of anestehtics in the CNS

78
Q

effectiv concentration of inhalation anesthetics

A

the rate at chich effective concentration achived in barin (induction) depends upon PK parameters of anesthetics, to achieve effective concentration in the CNS anesthetics requre to be transferred from alveoli to blood and from blood to brain

79
Q

characteristics of inhalational anesthetics which goveren anesthesia are

A

solublility in the blood (blood;gaspartition) (soluble form does not produce anesthesia, gas from enters the brain, so lower the blood:gas, the more rapid is induction, sloubility in fat (oil:gas partition) (hihger solubility in fat high potency

80
Q

solubiity in blood indicates

A

rapidity of onset

81
Q

solubitiy in fate indicates

A

potency – MAC will be less –less amt of the drug will be responsible to mobility

82
Q

blood gas coeff

A

measure of solubility in the blood, determins the rate of induction and reovery of ihalational anesthetics, lower the blood gas coeff, fater the induction and recovery–NO (.47—>but blood gas is low so faster but oil gas ratio is low so potency is very low, meaning lipid oil gas coeff is very low) –MAC is very high —only few molecules are required to raise its partial pressure in gth blood

83
Q

higher blood gas coeff

A

higher the coeff, slower induction and recovery (Halothane) –more molecules soluble in blood, hence slowly raises its partial pressure tension and onset of action

84
Q

NO produces

A

rapid action bic low blood gas coeff so rapid ly attains pp in gaseous form

85
Q

halothane produces

A

slow action bc high blood gas coeff

86
Q

rate of onset and recovery depend on

A

blood:gas ratio

87
Q

the more soluble the anesthetic in the blood

A

the slower the anesthesia

88
Q

high bood gas ratio

A

slow onset, slow recovery

89
Q

low blood gas ratio

A

fast onset, fast recovery

90
Q

higher oilgas coef

A

higer lipid solubility and potency will bi higher

91
Q

higher the lipid solubility

A

higher the potnecy eg. Halothane

92
Q

MAC

A

minium alveolar concentration (median alveolar concentration) –lowest conc of the anesthtic in pulmonary alveoli (% of the inspired air) needed to produce the immobility in response to painful stimuli (surgical) stimulus in 50% individuals –> ED50 for anesthetic agent

93
Q

MAC is a valid measure of

A

potency of inhalational anesthetics

94
Q

the more lipid soluble the anesthetic

A

the lower the MAC and greater the potency

95
Q

MAC values are

A

additive (lower in the presence of opiods or sedative-hypnotics—so requirement of the inhalational anesthetic will be less) ; also are lower in elderly–so will also requrie less of the drug to produce anesthesia

96
Q

concentration response curve

A

most inhalational anesthetics have a steep con-response curve.

97
Q

increasing conc by 1/3 MAC

A

makes almost all individuals immobile and 2-4 MAC is often lethal, so its not good to go above the MAC value

98
Q

relationship of oilgas and MAC

A

inverse

99
Q

relationship of oilgas and potency

A

direct

100
Q

relationship of MAC and potency

A

inverse

101
Q

nonhalogenated gas

A

nitrous oxide

102
Q

halogenated hydrocarbons

A

halothane, enflurane, isoflurane, desflurane, sevoflurane, methoxyflurane

103
Q

what drug produces nephrotoxicity

A

methoxyflurane

104
Q

what is the safest inhalational anesthetic

A

Nitrous oxide, no effect on respriation and heart, non toxic to liver, kidney and brain

105
Q

Nitrous oxide metabolism

A

does not occur and quickly removed form the body by lungs. Used as a carrer and adjuvant to other anesthetics

106
Q

NO mixture

A

70% N2O + 25-30% O2 + 0.2-2.0% another potent anesthetic _ employed for most surgical procedures

107
Q

Nitrous oxide effeects

A

weak anesthetic (surgical anesthesia cannot be produced on its own), good analgesic, but poor muscle relaxant (often neuromuscular blockers are required)

108
Q

NO and Second gas effect

A

N2O can concentrate the halogenated anesthetics in the alveoli when they are concoamitany adminstrered bc of its fast uptake from the alveolar gas, creating a vacuum space so the other drug is sucked in

109
Q

NO and Diffusion hypoxia

A

when flow of N2O is turend off at the ned of anesthesia, then its concentration int eh alveoli will be lower than in the blood. Consequently N2O floods in from the blood and alveolar gas are diluted with N2o, making pt breathe hypoxic mixture. To overcome this 100% oxygen should be adminsitered to patent unto N2O is washed out.

110
Q

NO can cause

A

pneumothroax and megaloblastic anemia

111
Q

NO with O2

A

has been used for dental and obstetric analgesia

112
Q

Halothane effects

A

potent anesthetic but weak analgesic, inductionis pleasant

113
Q

Halothan is also

A

vagomimetic and can cause bradycardia, produces dose dependent hypotension (to counter excessive hypotension during halothane anesthesia, a direct acting vasoconstricor phenylephrine is given)

114
Q

Halothane causes

A

direct depression of myocardial contractility by reducing intracellular Ca concentration, CO is reduced with deepening anesthesia, sensitizes heart to catecholamines

115
Q

what drug is preferred in asthmatics

A

Halothane, dialates bronchus

116
Q

halothane relaxes

A

skeltal and uterine musle and can be used in obstetrics when uterine relaxation is indicated

117
Q

halothane adverse effects

A

Halothane Hepatitis, Malignant hyperthermia (with all halogenated hydrocarbon anesthetics and musle relaxants succinylcholine—withdraw anestheitc mixtuer and give dantrolene)

118
Q

Halothane metabolism

A

metabolisme significantly (30%) to bromide, trifluoroacetate–responsible for rare heaptotoxicity

119
Q

Enflurane difference from halothane

A

less potent than halothane, but produces rapid induction and recovery, does not sensitize the heart to catecholamines (less chance of arrhythmias), greater potentiation of muscle relaxant, due to a more potent “curare-like” effect

120
Q

contraindications of enflurane

A

seizures (CNS excitation) occur at deeper levels so contraindicated in epileptics; caution in renal failure due to fluoride metabolite, pungent and may result in breath holding or couging and is less accepted by children

121
Q

Isoflurane

A

produces more rapid induction and recovery than halothane, widely used, less likeley than halothane to sensitize the heart to catecholamines or cause arrhythmias, dialates coronary vasculature, increase coronary blood flow and increase oxygen supply to heart - hence beneficial in pts with IHD (ischemic heart disease) ( safe in myocardial ischemia)

122
Q

Isoflurane effects

A

does not provoke seizures, hence preferred in neurosurgery, produces concentration dependent hypotension due to peripheral vasodialation, skeletal muscle relaxation is similar to enflurane, negligible metabolism hence less organ toxicity, postanesthetic nausea and vomiting is low

123
Q

Desflurane

A

induction and recovery very very fast (faster than isoflurane) hence preferred for outpt surgical procedures, less potent than Isoflurane, delivered through special vaporizer (due to low volatility), short-lived postanesthetic cognitive and motor impairment, irritates the air passage (pungent) – coughing, laryngospasm, and excessive secretion

124
Q

Desflurane similarites to isoflurane

A

degree of respiratory depression, musle relaxation, vasodialation and fall in BP, as well as maintained cardiac contractility and coronary circulation are like Isoflurane, lack of seizure provoking potential or arrhythmogenicity and absence of liver as well as kidney toxicity are similar to isoflurane

125
Q

Sevoflurane

A

fast induction and recovery, absence of pungency and airway irritancy, makes it pleasant and acceptable in pediatric pts, causes bronchodialation, useful for pts with respiratory difficulties, metabolized by liver releaseing fluoride ions, thus like enflurane, raises concerns about nephrotoxicity, inaddition it is very unstable compound, degrades to a nephrotoxic compound

126
Q

Neuroleptanalgesia/neuroleptanesthesia

A

characterized by analgesia, general quiexcnce, psychic indifference and intense analgesia without total unconsciousness, not commonly used, usually reserved where inhalational and or other parenteral anesthetics are relativley contraindicated

127
Q

fentanyl (opiods)

A

short acting

128
Q

droperidol

A

long acting neuroleptic

129
Q

neuroleptanalgesia causes

A

drowsiness but respons to commands, respiratory depression and extra pyramidal s/s seen, used for endoscopies, angiographies and minor operations

130
Q

Benzodizepiens as adjucnts

A

used for anxiolysis, amnesia, and sedation prior to induction of anesthesia, most frequenly used in perioperative period is midazolam (preferred), diazepam and lorazepam

131
Q

Analgesics

A

analgesics are administered with general anesthetics to reduce anesthetic requirment and minimize hemodynamic chanes produced by painful stimulation, opiods are commonly used for these purposes,

132
Q

major perenteral opiods given during perioperative period are

A

fentanyl (most common), sufentanil, alfentanil, remifentanil, meperidine and morphine

133
Q

neuromuscular blocking agens

A

purpose is to relax muscles of the jaw, neck, and airway and thereby facilityate lanryngoscopy and endotrachal intubation, during the induction of anesthesia

134
Q

exampls of neuromuscular blockers

A

pancuronium (non-depolarizing muslce relaxant), Succinylcholine (depolarizing muslce relaxant)

135
Q

Properties of ideal gas for the pt

A

pleasant non irritating, non flammable, should not cause nasea/vomiting, induction and recovery should be fast with no after-effect

136
Q

Properties of ideal gas for the surgeon

A

provide adequeate analgesia, immobility and muscle relaxation

137
Q

Properties of ideal gas for the anesthetist

A

administration should be easy, controllable and veratile, should have wide margin of safety, should not affect ehart, liver, and other organs, rapid adjustment in depth should be possible, should be cheap, stable and easily stored, should not react with rubber tubing or soda lime

Pharmacology 2 (12 decks)

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