MUSCLE RELAXANTS CH. 12
NAGELHOUT QUESTIONS AND
ANSWERS
*this is a tertiary amine that is used as an anticholinesterase for the brain (it acts like
neostigmine with CNS effects) - ANSWER-physostigmine
*what population might we see taking physostigmine; how might this affect muscle
relaxants? - ANSWER-Alzheimer's patientst (bc increases acetylcholine levels and acts
as CNS stimulant for these patients); could make muscle relaxants have longer effect
name the ultra short acting neuromuscular blocking agents - ANSWER-succ
name the short acting neuromuscular blocking agents - ANSWER-none available yet
name the intermediate acting neuromuscular blocking agents - ANSWER-atracurium
cisatracurium
vecuronium
rocuronium
(last 30-60minutes and dose dependent)
name the long acting neuromuscular blocking agents - ANSWER-pancuronium
(last 60-90 minutes and dose dependent)
how do we provide 100% muscle relaxation - ANSWER-when we fill up all of our muscle
receptor sites with agent
describe the difference between the efficacy of NMBAs - ANSWER-not much of a
difference between them bc it mainly depends on the % of NM receptors filled
what kind of muscle do the NMBAs block? - ANSWER-skeletal muscle NOT smooth or
cardiac muscle
how and why do NMBAs block the diaphragm? - ANSWER-in pharmacology, the
diaphragm acts like skeletal muscle
what are the 5 tests used for nerve stimulation - ANSWER-1. single twitch
2. TOF
3. double burst stimulation
4. tetanus
5. post tetanic count
,what is the most common nerve stim test? - ANSWER-TOF
*describe how to deliver single twitch nerve stim - ANSWER-single supramaximal
electrical stimulus ranging from 0.1-1 Hz.
hertz means ______ - ANSWER-frequency
*what can the single twitch tell us? - ANSWER-all or nothing test. can't tell you the %
paralyzed, but can tell you if the patient is 100% blocked (no twitch seen) or less than
100% (get some kind of twitch response)
*the single twitch is more of a ______ rather than _____ assessment - ANSWER-
qualitative; quantitative (quality of the twitch characteristics rather than the count bc you
can't differ for counts for single twitch)
*describe how TOF is delivered - ANSWER-series of 4 twitches at 2Hz every 0.5
seconds for 2 seconds.
*what can the TOF stim test tell us? - ANSWER-can tell us blockade from 70%-100%
*explain how double burst stimulation is done - ANSWER-two short bursts of 50Hz
tetanus separated by 0.75 seconds. compare the 1st and 2nd
formula for the TOF ratio - ANSWER-twitch 4 (T4) : twitch1 (T1)
*why would we use double burst stim over TOF? - ANSWER-they are similar, however
may be easier to detect fade than with TOF
*this nerve stim requires a baseline test to compare responses (before drug admin);
why? - ANSWER-single twitch; quality test versus quantity
*how to deliver tetanus nerve stim? - ANSWER-rapid delivery of 30, 50 or 100 Hz
stimulus for 5 seconds (remember that you need to actually hold the button for this long)
consideration when using tetanus - ANSWER-don't use on awake pt- painful
*when and how to deliver post-tetanic count nerve stim - ANSWER-do this when all the
other test fail to stimulate a twitch. we do this when TOF or DBS responses is absent. is
a 50Hz tetanus for 5 seconds, then wait 3 seconds, then deliver single twitches of 1Hz
for up to 20 seconds
*what does it mean when you have a higher # of twitches post-tetanic; lower too -
ANSWER-usually see between 1-8 twitches. The more you have then the closer you
are to reversal. If you see 1-2, probably will need to keep patient ventilated a bit in
PACU
, *def for onset time: - ANSWER-time from drug admin to maximum effect
*def for clinical duration: - ANSWER-time from drug admin to 25% recovery of the twitch
response
*def for total duration of action: - ANSWER-time from drug admin to 90% recovery of
twitch response
*def for recovery index: - ANSWER-time from 25% to 75% recovery of the twitch
response (once it starts to wear off, how quickly will it completely)
what is the train of four ratio? what does 90% tell us? - ANSWER-compares the 4th
twitch of TOF with 1st. when 4th twitch is 90% of 1st, then recovery is indicated
when is is best to use the ulnar nerve for nerve stim? - ANSWER-BEST to use facial
nerve for ONSET and the corrugator supercilii is better than the orbicularis oculi;
Use the ulnar nerve and adductor pollicus for measuring RECOVERY
*the ____ ____ muscle recovers faster than the adductor pollicis and recovers
approximately at the exact same time as the ______ - ANSWER-corrugator supercilli
(eyebrow); diaphragm
*you are reversing your patient and the corrugator supercilii muscle has complete return
of response. what should we do next? is it safe to extubate? - ANSWER-monitor
response at the adductor pollicis bc the peripheral is expected to lag behind the facial
nerve. not safe to extubate bc more residual paralysis is expected it you guide recovery
with corrugator supercilii
*what are the cardiac effects seen by using paralytics? what about for smooth muscle of
the bronchioles? what about for uterus?
what about for bowel?
what about sphincters? - ANSWER-cardiac muscle isnt affected, but the cardiac effects
are indirect bc that cause histamine and catecholamine release.
don't paralyze smooth muscle of the bronchioles, uterus, or bowel
sphincters are skeletal muscle and ARE affected
*true or false; one way to treat bronchospasm is with NMBA - ANSWER-FALSE! don't
paralyze smooth muscle, which is muscle in bronchioles. BUT you can treat
laryngospasm bc larynx behaves like skeletal muscle
*what is the most popular location we use for nerve stimulation (name the nerve and
muscle); name 2nd most common location with nerve and muscle - ANSWER-ulnar
nerve and adductor pollicus muscle (thumb adduction);
facial nerve is 2nd most common; orbicularis oculi (eyelid movement) and corrugator
supercili muscle is eyebrow movement down and inward
NAGELHOUT QUESTIONS AND
ANSWERS
*this is a tertiary amine that is used as an anticholinesterase for the brain (it acts like
neostigmine with CNS effects) - ANSWER-physostigmine
*what population might we see taking physostigmine; how might this affect muscle
relaxants? - ANSWER-Alzheimer's patientst (bc increases acetylcholine levels and acts
as CNS stimulant for these patients); could make muscle relaxants have longer effect
name the ultra short acting neuromuscular blocking agents - ANSWER-succ
name the short acting neuromuscular blocking agents - ANSWER-none available yet
name the intermediate acting neuromuscular blocking agents - ANSWER-atracurium
cisatracurium
vecuronium
rocuronium
(last 30-60minutes and dose dependent)
name the long acting neuromuscular blocking agents - ANSWER-pancuronium
(last 60-90 minutes and dose dependent)
how do we provide 100% muscle relaxation - ANSWER-when we fill up all of our muscle
receptor sites with agent
describe the difference between the efficacy of NMBAs - ANSWER-not much of a
difference between them bc it mainly depends on the % of NM receptors filled
what kind of muscle do the NMBAs block? - ANSWER-skeletal muscle NOT smooth or
cardiac muscle
how and why do NMBAs block the diaphragm? - ANSWER-in pharmacology, the
diaphragm acts like skeletal muscle
what are the 5 tests used for nerve stimulation - ANSWER-1. single twitch
2. TOF
3. double burst stimulation
4. tetanus
5. post tetanic count
,what is the most common nerve stim test? - ANSWER-TOF
*describe how to deliver single twitch nerve stim - ANSWER-single supramaximal
electrical stimulus ranging from 0.1-1 Hz.
hertz means ______ - ANSWER-frequency
*what can the single twitch tell us? - ANSWER-all or nothing test. can't tell you the %
paralyzed, but can tell you if the patient is 100% blocked (no twitch seen) or less than
100% (get some kind of twitch response)
*the single twitch is more of a ______ rather than _____ assessment - ANSWER-
qualitative; quantitative (quality of the twitch characteristics rather than the count bc you
can't differ for counts for single twitch)
*describe how TOF is delivered - ANSWER-series of 4 twitches at 2Hz every 0.5
seconds for 2 seconds.
*what can the TOF stim test tell us? - ANSWER-can tell us blockade from 70%-100%
*explain how double burst stimulation is done - ANSWER-two short bursts of 50Hz
tetanus separated by 0.75 seconds. compare the 1st and 2nd
formula for the TOF ratio - ANSWER-twitch 4 (T4) : twitch1 (T1)
*why would we use double burst stim over TOF? - ANSWER-they are similar, however
may be easier to detect fade than with TOF
*this nerve stim requires a baseline test to compare responses (before drug admin);
why? - ANSWER-single twitch; quality test versus quantity
*how to deliver tetanus nerve stim? - ANSWER-rapid delivery of 30, 50 or 100 Hz
stimulus for 5 seconds (remember that you need to actually hold the button for this long)
consideration when using tetanus - ANSWER-don't use on awake pt- painful
*when and how to deliver post-tetanic count nerve stim - ANSWER-do this when all the
other test fail to stimulate a twitch. we do this when TOF or DBS responses is absent. is
a 50Hz tetanus for 5 seconds, then wait 3 seconds, then deliver single twitches of 1Hz
for up to 20 seconds
*what does it mean when you have a higher # of twitches post-tetanic; lower too -
ANSWER-usually see between 1-8 twitches. The more you have then the closer you
are to reversal. If you see 1-2, probably will need to keep patient ventilated a bit in
PACU
, *def for onset time: - ANSWER-time from drug admin to maximum effect
*def for clinical duration: - ANSWER-time from drug admin to 25% recovery of the twitch
response
*def for total duration of action: - ANSWER-time from drug admin to 90% recovery of
twitch response
*def for recovery index: - ANSWER-time from 25% to 75% recovery of the twitch
response (once it starts to wear off, how quickly will it completely)
what is the train of four ratio? what does 90% tell us? - ANSWER-compares the 4th
twitch of TOF with 1st. when 4th twitch is 90% of 1st, then recovery is indicated
when is is best to use the ulnar nerve for nerve stim? - ANSWER-BEST to use facial
nerve for ONSET and the corrugator supercilii is better than the orbicularis oculi;
Use the ulnar nerve and adductor pollicus for measuring RECOVERY
*the ____ ____ muscle recovers faster than the adductor pollicis and recovers
approximately at the exact same time as the ______ - ANSWER-corrugator supercilli
(eyebrow); diaphragm
*you are reversing your patient and the corrugator supercilii muscle has complete return
of response. what should we do next? is it safe to extubate? - ANSWER-monitor
response at the adductor pollicis bc the peripheral is expected to lag behind the facial
nerve. not safe to extubate bc more residual paralysis is expected it you guide recovery
with corrugator supercilii
*what are the cardiac effects seen by using paralytics? what about for smooth muscle of
the bronchioles? what about for uterus?
what about for bowel?
what about sphincters? - ANSWER-cardiac muscle isnt affected, but the cardiac effects
are indirect bc that cause histamine and catecholamine release.
don't paralyze smooth muscle of the bronchioles, uterus, or bowel
sphincters are skeletal muscle and ARE affected
*true or false; one way to treat bronchospasm is with NMBA - ANSWER-FALSE! don't
paralyze smooth muscle, which is muscle in bronchioles. BUT you can treat
laryngospasm bc larynx behaves like skeletal muscle
*what is the most popular location we use for nerve stimulation (name the nerve and
muscle); name 2nd most common location with nerve and muscle - ANSWER-ulnar
nerve and adductor pollicus muscle (thumb adduction);
facial nerve is 2nd most common; orbicularis oculi (eyelid movement) and corrugator
supercili muscle is eyebrow movement down and inward
