Term
| inhalation general anesthetics currently in use (2)? |
|
Definition
1. nitrous oxide
2. halogenated aliphatics |
|
|
Term
| halogenated aliphatics (6) |
|
Definition
1. halothane
2. methoxyflurane
3. enflurane
4. isoflurane
5. desflurane
6. sevoflurane |
|
|
Term
| IV general anesthetics currently in use (7)? |
|
Definition
1. barbiturates - thiopental, methohexital
2. benzodiazepines - diazepam, lorazepam, midazolam
3. ethomidate
4. opioid analgesics - morphine, meperidine, fentanyl
5. propofol
6. dexmedetomidine
7. ketamine |
|
|
Term
| what are the 5 characteristics of general anesthesia? |
|
Definition
1. loss of consciousness
2. analgesia
3. amnesia
4. skeletal muscle relaxation
5. inhibition of autonomic and sensory reflexes |
|
|
Term
| what is the Ostwald coefficient? |
|
Definition
the blood:gas partition coefficient
the ratio of concentration of anesthetic in blood to the concentration of anesthetic in the gas phase when the partial pressure of the anesthetic is equal in both phases (ie at equilibrium) |
|
|
Term
| how is the Ostwald coefficient used in anesthesia? |
|
Definition
| its the primary determinant of the rate of onset (and rate of reversal) of anesthesia |
|
|
Term
| what is the primary determinant of the rate of onset (and rate of reversal) of anesthesia? |
|
Definition
|
|
Term
| what does the size of the Oswald coefficient tell you? |
|
Definition
| the larger the Oswald coefficient, the longer it takes to reach equilibrium, therefore, induction time is slower |
|
|
Term
| how does the Oswald coefficient relate to induction time? |
|
Definition
| the larger the Oswald coefficient, the slower the induction time (the longer it takes to reach equilibrium) |
|
|
Term
| what is lipid solubility? |
|
Definition
| ability of any agent to mix or dissolve in a lipid phase |
|
|
Term
| anesthetics with high lipid solubility require what? |
|
Definition
| more gas to achieve a significant partial pressure in the blood and tissues |
|
|
Term
| why is lipid solubility important in induction and recovery from anesthesia? |
|
Definition
| anesthetics with high lipid solubility require more gas to achieve a significant partial pressure in the blood and tissues so induction and recovery from anesthesia are slower |
|
|
Term
| what is equilibrium of inhalation anesthetics? |
|
Definition
| the state reached when the partial pressure of the gaseous anesthetic is the same in all biophases |
|
|
Term
| what do the actual concentration of inhalation anesthetic agents in each biophase depend on in equilibrium? |
|
Definition
| the solubility of agent in the different compartments |
|
|
Term
| at equilibrium, what is equal for each phase of the anesthetic? |
|
Definition
partial pressures are equal
concentrations of anesthetic in each phase are not equal |
|
|
Term
|
Definition
| minimal alveolar concentration |
|
|
Term
| what does the MAC value describe? |
|
Definition
the potency of an inhalation anesthetic agent
the lower the MAC value, the more potent the agent |
|
|
Term
| the most potent an inhalation anesthetic, the ____ the MAC value |
|
Definition
|
|
Term
| what is the objective of the induction of anesthesia? |
|
Definition
| to produce an appropriate concentration or partial pressure of the anesthetic agent in brain tissue |
|
|
Term
| what happens in phase 1 of anesthesia induction? |
|
Definition
| establishment of an equilibrium between the inspired mixture and the lungs |
|
|
Term
| what 3 things does phase 1 of anesthesia induction depend on? |
|
Definition
1. initial concentration of gas in the inspired mixture
2. amount inhaled
3. second-gas effect |
|
|
Term
| how does a high partial pressure of the gas in the lungs change the attainment of equilibrium in phase 1 of anesthesia induction? |
|
Definition
| high partial pressure of the gas in the lungs results in more rapid attainment of equilibrium |
|
|
Term
| how can the amount of anesthetic inhaled be regulated? |
|
Definition
by changing the rate and/or depth of respiration (pulmonary ventilation)
deeper breathing = more inhaled
shallow breathing = less anesthetic inhaled |
|
|
Term
| how can pre-anesthetic medications increase time to reach equilibrium for anesthesia? |
|
Definition
| some decrease resp thereby increasing the time to reach equilibrium |
|
|
Term
| what is the second-gas effect of phase 1 of anesthesia induction? |
|
Definition
a rapidly absorbed gas (nitrous oxide) increases the rate of uptake of a second anesthetic gas (halothane)
this allows equilibrium to be reached faster |
|
|
Term
| what is a reason that nitrous oxide is frequently used in combo with other inhalation anesthetics? |
|
Definition
the second-gas effect
allows equilibrium to be reached faster because it increases the rate of uptake of a second anesthetic gas |
|
|
Term
| what happens in phase 2 of anesthesia induction? |
|
Definition
| passage of the anesthetic from alveoli to the blood in pulmonary capillaries |
|
|
Term
| what 2 things is phase 2 of anesthesia induction dependent on? |
|
Definition
1. the blood:gas partition (Ostwald) coefficient
2. the partial pressure differences of the agent in the alveoli vs. the blood |
|
|
Term
| how does the Ostwald coefficient affect phase 2 of anesthesia induction? |
|
Definition
| drugs with low blood solubility (low coefficient, like nitrous oxide) equilibrate more rapidly than do drugs with a higher partition coefficient (halothane or methoxyflurane) |
|
|
Term
| how do the partial pressure differences of the anesthetic agent in alveoli vs. the blood affect phase 2 of induction of anesthesia? |
|
Definition
| as blood becomes closer to saturation with the anesthetic - the slower the rate of transfer of anesthetic from the alveoli to the blood |
|
|
Term
| what affect does drug equilibration with the blood have on the agent passing to the brain? |
|
Definition
| the more rapidly a drug equilibrates with the blood - the more quickly it passes into the brain to produce its anesthetic effects |
|
|
Term
| what happens in phase 3 of anesthesia induction? |
|
Definition
| passage of gas from the blood into tissues of the body, especially the brain |
|
|
Term
| what 3 things is phase 3 of induction of anesthesia dependent on? |
|
Definition
1. solubility of gas in tissue
2. partial pressure in the blood relative to tissues
3. tissue blood flow |
|
|
Term
| how is phase 3 of induction of anesthesia dependent on the solubility of gas in tissue? |
|
Definition
| related to how quickly equilibrium is reached between blood and tissue |
|
|
Term
| how is the solubility of gas in tissue expressed? |
|
Definition
as the tissue:blood partition coefficient
solubility in brain, muscle, kidney, etc relative to blood |
|
|
Term
| how does the solubility of gas in lean tissues compare to blood? |
|
Definition
|
|
Term
how does the solubility of gas in fatty tissues compare to blood?
why is this important? |
|
Definition
fatty tissues is greater
it takes longer to reach equilibrium in these tissues |
|
|
Term
| the rate at which tissue takes up gas in phase 3 of induction of anesthesia is directly dependent upon what? |
|
Definition
| the difference in partial pressure between the tissue and the blood |
|
|
Term
| at early times in phase 3 of induction of anesthesia tissue takes up gas ____ but _____ as ____ approaches? |
|
Definition
quickly
slows down
saturation |
|
|
Term
| how does tissue blood flow play a role in phase 3 of induction of anesthesia? |
|
Definition
| highly perfused organs (brain, heart, kidneys) reach equilibrium faster than poorly perfused organs or tissues such as body fat |
|
|
Term
| how does anesthetic tension (partial pressure) in the blood rise toward that in inspired air in the induction of inhalation anesthesia? |
|
Definition
rapidly at first
then more slowly |
|
|
Term
| how does the Ostwald coefficient related to rate of induction of inhalation anesthesia? |
|
Definition
| the less soluble the anesthetic in the blood (low blood:gas or Ostwald coefficient) - the faster the rate of induction |
|
|
Term
| how does increasing alveolar ventilation affect rate of induction of inhalation anesthesia? |
|
Definition
|
|
Term
| how does the concentration of inspired anesthetic affect rate of induction of inhalation anesthetic? |
|
Definition
| as the concentration is increased, the rate of induction is increased |
|
|
Term
| how do tissue concentrations change with induction of inhalation anesthesia? |
|
Definition
increase rapidly at first then more slowly as they approach the blood concentration (tension)
gas moves from a compartment of higher partial pressure to a lower partial pressure compartment |
|
|
Term
| where in the body does partial pressure increase most rapidly with induction of inhalation anesthesia? |
|
Definition
| in lean tissues and/or organs with a high rate of blood flow |
|
|
Term
| how can drugs or diseased states affect the rate of induction of inhalation anesthesia? |
|
Definition
slower in obese than in lean individuals
slower if pulmonary status is poor
individual variation also plays a role |
|
|
Term
| the vast majority of inhalation anesthetics are eliminated how? |
|
Definition
| largely unchanged via the lungs |
|
|
Term
| how are inhalation anesthetic gases eliminated? |
|
Definition
|
|
Term
| how does ventilation rate after removal of the anesthetic affect recovery from inhalation anesthesia? |
|
Definition
| the higher the ventilation rate after removal of the anesthetic - the faster the recovery |
|
|
Term
| how does solubility of an inhalation anesthetic in blood or in lipids affect the recovery from the drug? |
|
Definition
| the lower the solubility - the faster the recovery |
|
|
Term
| what is the MAC (minimal alveolar concentration) value? |
|
Definition
| defined as the minimum alveolar concentration at steady-state (measured in V/V %) which results in immobility in 50% of individuals when exposed to a noxious stimulus, such as surgical incision |
|
|
Term
| what is MAC independent of? |
|
Definition
time
MAC is the alveolar concentration at equilibrium and is independent of the time required to reach this level (ie. induction time) |
|
|
Term
| does the MAC vary for different drugs and/or patients? |
|
Definition
| each anesthetic has a defined MAC, but this concentration may vary among patients depending on age, pulmonary status, use of adjuvant drugs, etc |
|
|
Term
| how does the MAC value relate to anesthetic potency? |
|
Definition
| the lower the MAC value - the more potent the anesthetic |
|
|
Term
| what 4 things cause the MAC value to decrease? |
|
Definition
1. presence of adjuvant drugs - other anesthetics, opioids, sedative-hypnotics
2. hypothermia
3. hypotension
4. age |
|
|
Term
|
Definition
| the percentage of anesthetic needed in the inspired air to obtain immobility in 50% of individuals |
|
|
Term
| how do MAC values range among anesthetic agents? |
|
Definition
|
|
Term
| how is potency related to MAC value? |
|
Definition
|
|
Term
|
Definition
|
|
Term
| what does nitrous oxide having a MAC value of more than 100 indicate? |
|
Definition
| that immobility could be achieved only under hyperbaric conditions |
|
|
Term
| how is lipid solubility of inhalation anesthetics related to anesthetic potency? |
|
Definition
directly related
the more lipid soluble an inhalation anesthetic - the higher the potency (and therefore the lower the MAC value) |
|
|
Term
| general anesthetics mechanism of action? |
|
Definition
| influence synaptic transmission rather than axonal conductance |
|
|
Term
| what are the prime targets for most general anesthetics? |
|
Definition
post-synaptic ligand gated ion channels
especially GABAa receptors |
|
|
Term
| effect of all anesthetics except ketamine at the GABAa receptor? |
|
Definition
| potentiate the actions of GABA (the principal inhibitory NT in the CNS) |
|
|
Term
| what is the only anesthetic agent that doesn't potentiate the actions of GABA? |
|
Definition
|
|
Term
| how do general anesthetics (except ketamine) work at the GABA receptor? |
|
Definition
| at clinical concentrations they increase GABA induced chloride current by over 50% by increasing the affinity of GABA for GABAa receptors |
|
|
Term
| how do general anesthetics increase GABA induced chloride current? |
|
Definition
| by increasing the affinity of GABA for GABAa receptors |
|
|
Term
| what general anesthetic differs in its mechanism of action? |
|
Definition
|
|
Term
| ketamine mechanism of action? |
|
Definition
| selectively inhibits the NMDA receptor --> thus interfering with the action of L-glutamate (the major excitatory NT in the CNS) |
|
|
Term
| what are the 4 stages of anesthesia? |
|
Definition
1. induction
2. excitement
3. operative
4. danger |
|
|
Term
| what is seen in stage 1 (induction) of anesthesia? |
|
Definition
constricted pupils
rapid resp rate
irregular pulse rate
normal BP |
|
|
Term
| what is seen in stage 2 (excitement) of anesthesia? |
|
Definition
pupils often dilate
rapid resp rate
irregular pulse rate
high BP |
|
|
Term
| what is seen in stage 3 (operative) of anesthesia? |
|
Definition
slightly dilated pupil
shallow and slow resp rate
steady and shallow pulse rate
normal BP |
|
|
Term
| what is seen in stage 4 (danger) of anesthesia? |
|
Definition
extremely dilated pupil
very slow resp rate
weak pulse rate
very low BP |
|
|
Term
| what stage of anesthesia do you want to minimize a patient's time in? |
|
Definition
|
|
Term
| what stage of anesthesia is the goal? |
|
Definition
stage 3 - operative
want to get them there quickly and keep them there |
|
|
Term
| when does stage 4 (danger) of anesthesia occur and what is the result? |
|
Definition
occurs if anesthesia goes too far and is not controlled
results in resp collapse |
|
|
Term
| how does the degree of skeletal muscle relaxation change with the stages of anesthesia? |
|
Definition
| degree of skeletal muscle relaxation increases with increasing depth |
|
|
Term
| what are the most reliable signs of stage 3 anesthesia? |
|
Definition
1. loss of eyelash (corneal) reflex
2. a pattern of resp that is regular in rate and depth |
|
|
Term
| why are the stages of anesthesia more obscure in the new, more potent agents? |
|
Definition
| they progress through the stages more rapidly |
|
|
Term
| what 2 things can obscure the signs which indicate the depth of anesthesia? |
|
Definition
1. mechanical ventilation
2. use of adjunct drugs |
|
|
Term
| why is a combination of anesthetic drugs use? |
|
Definition
| to take advantage of individual pharmacological properties while attempting to minimize or counteract the adverse effects of anesthetic agents |
|
|
Term
| use of a single anesthetic agent on its own is ____ and distinct stages of anesthesia are ____ |
|
Definition
now uncommon
seldom observed in practice |
|
|
Term
| anesthetic procedures are designed to eliminate what stage(s)? |
|
Definition
|
|
Term
| does metabolism of inhalation anesthetics occur? |
|
Definition
|
|
Term
what is metabolism of inhalation anesthetics not a factor in determining?
what does it contribute to? |
|
Definition
duration of action
toxicity |
|
|
Term
| halothane metabolites include what 3 things? |
|
Definition
1. bromide ion
2. chloride ion
3. trifluoroacetic acid |
|
|
Term
| what adverse side effect has been reported from repeated halothane administration? |
|
Definition
hepatotoxicity
incidence is low |
|
|
Term
| what is the major toxic metabolite of methoxyflurane? |
|
Definition
|
|
Term
| how much do plasma fluoride levels increase following anesthesia with methoxyflurane? |
|
Definition
| from normal (2 umol/L) to 40-80 umol/L and remain high for several days |
|
|
Term
| high levels of fluoride after anesthesia with methoxyflurane can cause what? |
|
Definition
|
|
Term
| what is an adverse side effect of inhalation anesthetics that causes a rapid rise in body temp and body rigidity? |
|
Definition
|
|
Term
| what is characteristic of malignant hyperthermia as an adverse effect of inhalation anesthetics? |
|
Definition
1. rapid rise in body temp
2. increase in oxygen consumption and CO2 production
3. leads to body rigidity |
|
|
Term
| why is there an increase in oxygen consumption and CO2 production in malignant hyperthermia? |
|
Definition
| due to excessive release of Ca from the SR |
|
|
Term
| what is the drug of choice for prevention and treatment of malignant hyperthermia and how does it work? |
|
Definition
dantrolene
blocks the release of Ca |
|
|
Term
| what is the incidence of malignant hyperthermia with use of inhalation anesthetics and what increases this risk? |
|
Definition
1:250,000
increases 50 fold with use of succinylcholine in genetically susceptible individuals |
|
|
Term
| what is the risk in patients with brain tumor or head injury given inhalation anesthetics? |
|
Definition
| increase in cerebral blood flow by the rise in pCO2 may increase ICP |
|
|
Term
| how is the risk reduced for increase ICP in patients with brain tumor or head injury given inhalation anesthetics? |
|
Definition
| patient is hyperventilated before anesthesia |
|
|
Term
| desired features of anesthesia (9)? |
|
Definition
1. smooth and rapid induction and recovery
2. analgesia and amnesia
3. sedation
4. muscle relaxation
5. ease of providing moment to moment control
6. safe to handle - non-flammable, non-explosive
7. no adverse effects - esp CV
8. no long term toxicity - to liver or kidney
9. non-irritating both pre and post op - no nausea and vomiting |
|
|
Term
| 5 objective to pre-anesthetic meds? |
|
Definition
1. decrease patient anxiety level
2. facilitate smooth and rapid induction
3. decrease muscle tone
4. alleviate undesirable side effect of anesthetics - nausea, vomiting, increased secretions
5. relieve pre and post op pain |
|
|
Term
| 7 classes of pre-anesthetic meds? |
|
Definition
1. anxiolytics - benzodiazepines
2. sedative-hypnotics - barbiturates
3. opiates - morphine, fentanyl
4. anti-emetics - droperidol, metoclopramide
5. anti-GI effects - H2 receptor antagonists - cimetidine
6. muscle relaxants - succinylcholine
7. anti-cholinergics - glycopyrrolate - to decrease secretions |
|
|
Term
| structure of all general anesthetic agents except nitrous oxide and halothane |
|
Definition
|
|
Term
| what progressively replaces other halogens in the development of the halogenated anesthetic agents? |
|
Definition
|
|
Term
| all structural differences in general anesthetics are associated with what? |
|
Definition
| important differences in pharmacological properties |
|
|
Term
| properties of nitrous oxide? |
|
Definition
non-halogenated gas
MAC = 100+
weak anesthetic
good analgesic with sedative qualities |
|
|
Term
| long term use of nitrous oxide leads to what? |
|
Definition
1. B12 deficiency
2. neuropathy
3. leukopenia |
|
|
Term
| what was the first halogenated anesthetic? |
|
Definition
|
|
Term
|
Definition
| fair analgesic and skeletal muscle relaxant |
|
|
Term
| how does halothane cause cardiac arrhythmia? |
|
Definition
| sensitizes the heart to catecholamines |
|
|
Term
| side effect of halothane? |
|
Definition
| sensitizes heart to catecholamines --> can cause cardiac arrhythmia |
|
|
Term
| is halothane metabolized? |
|
Definition
|
|
Term
| what inhalation anesthetic is highly metabolized? |
|
Definition
|
|
Term
| methoxyflurane characterisitcs? |
|
Definition
slow induction and emergence
highly metabolized - 70% |
|
|
Term
| why is methoxyflurane no longer used? |
|
Definition
| due to high rate of metabolism with release of fluoride |
|
|
Term
| induction and emergence of enflurane? |
|
Definition
|
|
Term
|
Definition
| good analgesic and hypnotic |
|
|
Term
| side effects of enflurane? |
|
Definition
minimal CV effects
very small amount of metabolism with release of fluoride |
|
|
Term
| induction and emergence of isoflurane? |
|
Definition
|
|
Term
|
Definition
| good analgesic and hypnotic |
|
|
Term
| side effects of isoflurane? |
|
Definition
|
|
Term
| metabolism of isoflurane? |
|
Definition
NO metabolism
NO fluoride release |
|
|
Term
| how do circulatory and resp depression of desflurane compare to that of halothane, enflurane, and isoflurane? |
|
Definition
| at deep levels of anesthesia - they are similar |
|
|
Term
| solubility of desflurane? |
|
Definition
lower solubility
similar to that of nitrous oxide |
|
|
Term
|
Definition
used most where rapid onset and rapid recovery are desirable
e.g. ambulatory surgery |
|
|
Term
| what is the newest inhalation anesthetic? |
|
Definition
|
|
Term
|
Definition
low MAC value - 2%
induction and recovery are intermediate between that of isoflurane and desflurane |
|
|
Term
| which acts more rapidly: inhalation or IV anesthetics? |
|
Definition
|
|
Term
|
Definition
| primarily for induction of anesthesia followed by inhalation agent |
|
|
Term
| IV anesthetics are usually followed by what? |
|
Definition
|
|
Term
| IV anesthetics allow for what? |
|
Definition
lower doses of inhalation anesthetic to be used
decrease MAC |
|
|
Term
| IV anesthetics induce what? |
|
Definition
sedation
analgesia
amnesia
relaxation
control of visceral reflex responses |
|
|
Term
| how do you acquire more precise control of the required effect of IV anesthetics? |
|
Definition
| with combination of agents with different actions |
|
|
Term
are IV anesthetics alone satisfactory for producing maintained anesthesia?
why or why not? |
|
Definition
NO
due to slower elimination from the body and therefore less easily controlled emergence |
|
|
Term
| what IV anesthetics are widely used as an induction agent? |
|
Definition
|
|
Term
| what do barbiturates produce? |
|
Definition
sedation
but not analgesia or muscle relaxation |
|
|
Term
|
Definition
|
|
Term
| why do barbiturates have rapid action? |
|
Definition
| due to very high lipid solubility and rapid transfer across BBB |
|
|
Term
| why do barbiturates have short duration? |
|
Definition
|
|
Term
| metabolism of barbiturates? |
|
Definition
| slowly metabolized and liable to accumulate in body fat |
|
|
Term
| what is important about dosing for barbiturates? |
|
Definition
| there is a narrow margin between the anesthetic dose and a dose causing CV depression |
|
|
Term
| why are benzodiazepines useful in pre-anesthetic medication? |
|
Definition
| for their sedative and anti-anxiety properties |
|
|
Term
| how are benzodiazepines used in anesthesia? |
|
Definition
| to supplement or induce and maintain anesthesia |
|
|
Term
| action of benzodiazepines compared to barbiturates? |
|
Definition
|
|
Term
| do benzodiazepines cause resp or CV depression? |
|
Definition
|
|
Term
|
Definition
for induction of anesthesia
very short acting hypnotic - fast onset, fairly fast recovery |
|
|
Term
| does etomidate have analgesic properties? |
|
Definition
|
|
Term
| how does etomidate compare to thiopental? |
|
Definition
larger margin of safety between anesthetic dose and dose that produces resp and CV depression
more rapidly metabolized |
|
|
Term
| why is etomidate not used for total anesthesia? |
|
Definition
| due to risk of toxicity (adrenocortical suppression) at high doses |
|
|
Term
| side effects of etomidate during induction and recovery? |
|
Definition
| may cause involuntary movements |
|
|
Term
| opioid analgesics used as supplements during general anesthesia with inhalation or IV agents (5)? |
|
Definition
1. morphine
2. meperidine
3. fentanyl
4. sulfentanil
5. alfentanil |
|
|
Term
| where do opioid analgesics act? |
|
Definition
| opioid receptors - not GABA receptors |
|
|
Term
| opioid analgesics use for anesthesia? |
|
Definition
used as supplements during general anesthesia with inhalation or IV agents
rapid onset of analgesia |
|
|
Term
| side effects of opioid analgesics? |
|
Definition
may cause resp depression
some delay in awakening
post-op nausea and vomiting |
|
|
Term
| what can be used to reverse resp depression caused by opioid analgesics? |
|
Definition
| specific opioid antagonists - naloxone |
|
|
Term
opioid analgesics can be combined with what to produce neuroleptic analgesia or anesthesia?
what is an example of this? |
|
Definition
neuroleptic drug
fentanyl + droperidol |
|
|
Term
|
Definition
1. rapidly acting - induces anesthesia as rapidly as does thiopental
2. rapidly metabolized
3. very rapid recovery - no cumulative effect |
|
|
Term
| can propofol be used for total IV anesthesia? |
|
Definition
|
|
Term
| side effects of propofol? |
|
Definition
|
|
Term
| Dexmedetomidine drug type? |
|
Definition
| alpha2-adrenergic receptor agonist |
|
|
Term
|
Definition
| approved for sedation of initially intubated and mechanically ventilated patients during treatment in ICU |
|
|
Term
| Dexmedetomidine analgesic properties? |
|
Definition
|
|
Term
|
Definition
continuous infusion
<24 hr to avoid adverse side effects such as bradycardia |
|
|
Term
| adverse side effects of Dexmedetomidine? |
|
Definition
|
|
Term
| how can bradycardia as an adverse side effect of Dexmedetomidine be avoided? |
|
Definition
| infusions should be administered for <24 hours |
|
|
Term
| does Dexmedetomidine reliable provide general anesthesia alone? |
|
Definition
|
|
Term
| effect of Dexmedetomidine in combination with inhalation anesthetics? |
|
Definition
| can decrease the MAC value by as much as 90% |
|
|
Term
| what is anesthetic sparing? |
|
Definition
| Dexmedetomidine in combination with inhalation anesthetics can decrease the MAC value by as much as 90% |
|
|
Term
| Dexmedetomidine resp depression? |
|
Definition
|
|
Term
|
Definition
differs from other anesthetic agents
related to effect on NMDA type glutamate receptors |
|
|
Term
|
Definition
| related to phencyclidine (PCP) |
|
|
Term
| ketamine produces what type of anesthesia? |
|
Definition
|
|
Term
| what is dissociative anesthesia? |
|
Definition
| patient may remain conscious though amnesic and insensitive to pain |
|
|
Term
| what anesthetic produces dissociative anesthesia? |
|
Definition
|
|
Term
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Definition
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Term
| what 2 effects of ketamine are rapidly established? |
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Definition
| intense analgesia and amnesia |
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Term
| ketamine onset of action? |
|
Definition
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Term
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Definition
analgesia persists for 40 mins
amnesia for 1-2 hours |
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Term
| ketamine side effects during recovery? |
|
Definition
high incidence of dysphoria, hallucinations, unpleasant dreams, delirium, etc
less in children |
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Term
| side effects of ketamine are seen less in? |
|
Definition
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Term
|
Definition
mainly - minor procedures in children
also useful for trauma and emergency surgical procedures |
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Term
| how can you reduce adverse effects of ketamine? |
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Definition
| by prior admin of a benzodiazepine |
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Term
An 8 yo asthmatic child is to undergo appendectomy. Anesthetized with mix of sevoflurane and Nitrous Oxide. The sevoflurane is delivered at a dose 1.2 times higher than its MAC. Why was it delivered at a dose higher than MAC value?
a. Because addition of NO increases MAC
b. Because addition of NO decreases MAC
c. To ensure that the child remained anesthetized for the duration of surgery
d. Because children require a higher dose of inhalation anesthetics
e. Because the child has a respiratory problem |
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Definition
| d. Because children require a higher dose of inhalation anesthetics |
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Term
An Anesthesiologist has a choice between 2 inhalation anesthetics. Agent A provides a very rapid rate of induction and recovery while both induction and recovery are slower with agent B. This difference can be explained by:
a. A has a higher blood: gas partition coefficient
b. A is more soluble in lipid
c. A has a higher vapor pressure
d. A has lower blood solubility
e. MAC for A is 1% and B is 2% |
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Definition
| d. A has lower blood solubility |
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Term
Maintaining anesthesia at 1 MAC of Halothane in one patient and at 1 MAC of enflurane in another patient means that :
a. The partial pressure in the alveolar space will be identical in each patient
b. The partial pressure of both agents in the brain will be identical
c. Anesthesia will be deeper with the more potent agent
d. The probability that either patient will move on skin incision is the same |
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Definition
| d. The probability that either patient will move on skin incision is the same |
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