Nagelhout Video 1 - Exam 1 Flashcards
Ultra-short neuromuscular depolarizing relaxants
Succinylcholine
Intermediate neuromuscular non-depolarizing relaxants
Vecuronium (Norcuron)
Cis-astracurium (Nimbex)
Atracurium (Tracrium)
Rocuronium (Zemuron)
Long acting non-depolarizing neuromuscular relaxants
pancuronium
Why is succyinylcholine considered depolarizing?
Because it is (essentially) Acetylcholine - it causes the muscle to contract or depolarize once
There is a period of paralysis while waiting for Succs to leave the synapse.
How do non-depolarizing neuromuscular agents work?
Like classic antagonists- they do not cause muscle contraction
What percent of muscle receptors is required for patient to have normal tidal volume / RR?
What are the implications of this?
20% of receptors
-pt could be 80% paralyzed, poor airway reflexes but have normal respirations
-this is why it’s important to know how many receptors are still occupied by a neuromuscular relaxant before extubating
You can’t be more than 100% paralyzed - what are the implications of this?
the more relaxant you give, the harder to get rid of the drug at the end of the case - the less relaxant you use the easier reversal will be
What type of muscle do neuromuscular relaxants work on?
Skeletal muscle only not cardiac or smooth muscle
What OR procedures require patient to be paralyzed?
Abdominal or chest procedures
When you give a neuromuscular blockade will this work on the bowel?
No because it is smooth muscle - but it will work on sphincter causing them to open up
*Which makes a patient susceptible to aspiration
Single Twitch test
single supramaximal electrical stimulus ranging from 0.1-1.0 Hz
Which Nerve stimulation test provides the least amount of information?
Single-twitch
What does the single twitch test require and what type of information does it represent?
requires a baseline assessment
QUALITATIVE not quantitative
- If they move they’re not paralyzed
- IF they don’t they are
Which Nerve stimulation test is the most popular?
Train-of-four
Train of Four (TOF)
-timing
-results
A series of 4 twitches at 2 Hz. every half-second for 2 seconds
Train-of-four ratio is determined by comparing T1-T4 (looking for fade)
Reflects blockade from 70-100%
Double burst stimulation
two bursts of 50 hz tetanus separated by 0.75 seconds
Compare the first and second twitch - look for fade (fade may be easier to detect than TOF)
Tactile evaluation
Tetanus
-energy used, process of
Rapid delivery of a 30, 50, or 100- Hz.
Stimulus for 5 seconds.
Should be used sparingly for deep block assessment - painful
Post- tetanic count
-Energy used and process
50-Hz. tetanus for 5 seconds, a 3-second pause, then single twitches of 1 Hz.
Tetantic should only be used when which two tests are absent?
Used only when TO4 or double-burst stimulation response is absent;
Tetanic: less than 8 indicates
<8 indicates a deep block and likely prolonged recovery.
Onset
time from drug administration to maximum effect
Clinical Duration of NMBD is usually
time from drug administration to 25% recovery of the twitch response
-DOA of a NMBD = time of recovery of 1/4 TOF twitches
Recovery index
Time from 25% to 75% recovery of the twitch response
Total Duration
Time from drug administration to 90% recovery of the twitch response
*This is the number we use to determine recovery time!
Train of Four Ratio (TOFR)
Compares the 4th twitch of a TOF with the 1st twitch.
When the 4th twitch is 90% of the first, recovery is indicated
Electricity flows from positive to negative, so it flows from what color electrode to what color electrode?
Flows from the red electrode to the black electrode.
Red electrode should be closest to…
the body (proximal)
The black lead should be closest to..
the twitch site (distal)
Think red goes closest to heart
