RSI, NMB, NMB Reversal SEM1 Flashcards
MODULE QUIZ QUESTION
Neostigmine reverses neuromuscular blockade through which of the following actions?
A. Enhancement of Acetylcholinesterase at the neuromuscular junction
B. Direct agonism of the nicotinic receptors
C. Inhibition of acetylcholinesterase at the neuromuscular junction
D. Chelates and decreases free Rocuronium, causing passive diffusion away from the neuromuscular junction
C
MODULE QUIZ QUESTION
Sugammadex works to reverse neuromuscular blockade caused by Rocuronium through which of the following?
A. Inhibition of acetylcholinesterase at the neuromuscular junction
B. Direct agonism of the nicotinic receptors
C. Enhancement of Acetylcholinesterase at the neuromuscular junction
D. Chelates and decreases free Rocuronium, causing passive diffusion away from the neuromuscular junction
D
MODULE QUIZ QUESTION
Which of the following is true regarding the pharmacokinetics of Sugammadex?
A. It is bound to plasma proteins
B. It is excreted unchanged renally and enhances Rocuronium renal excretion
C. Its rate of excretion is dose dependent and requires intact renal function
D. It is metabolized hepatically and metabolites excreted in the urine
B
MODULE QUIZ QUESTION
Neostigmine causes which of the following adverse reactions.
Select ALL that apply.
A. Urinary retention B. Fasciculations C. Bronchoconstriction D. Bradycardia E. Hepatotoxicity F. Tachyarrhythmias
B and D
What is Sugammadex used for ?
is used to reverse the effects of the muscle relaxants ROCUronium and VECUronium
What is the brand name for Sugammadex?
Bridion
How does Sugammadex work ?
Binds to the neuromuscular blocking agents ROCUronium or VECUronium to form a complex
It does not affect the release or breakdown of acetylcholine.
The reduction of free rocuronium available in the blood plasma creates a concentration gradient at the neuromuscular junction.2
resulting in a a shift of rocuronium into the plasma, where it is encapsulated by Sugammadex
This process reduces the amount of neuromuscular blocking agent available to bind to nicotinic cholinergic receptors in the neuromuscular junction, resulting in the reversal of neuromuscular blockade.
ROCUronium - is it a depolarizing or non-depolarizing NMB ? An Agonist or Antagonist ?
NON-Depolarizing (therefore a COMPETITIVE ANTAGONIST of ACh Receptors at the NMJ)……so how would you reverse this ? (it will come up in another question)
How to you reverse NMB caused by ROCUronium ?
Use an ANTICHOLINESTERASE INHIBITOR, such as Neostigmine or Physostigmine.
ROC works as a competitive antagonist at the Ach R at the NMJ. So if you increase Ach, by blocking the breakdown of ACh by blocking the the enzyme Anticholinesterase, then Ach will outcompete ROC, and NMB will be reveresed
What are you option to reverse ROCuronium (or VECuronium) ?
Neostigmine / Physostigmine (AChesterase Inhibitor), or Sugamadex - Chelating agent that binds to ROC or VERcuronium.
What is the typical dosing of ROC ? And appox time of Onset ?
1 .2 mg/kg (TBW) ; 45 - 60 seconds
Neostigmine is mostly used for ?
Reversal of Non-Depolarizing NMB agents. Ex: Rocuronium.
Physostigmine is used mostly for what ?
Can be used to reverse NMB for Non Depolarizing NMB agents (ROC). But we typically use Neostigmine for that.
On the other hand, Physostigmine is often the choice to REVERESE ANTICHOLINERGIC TOXIDROME (not ENOUGH Ach activity)…..by blocking Anticholinesterase, Ach increases,,,
Physostigmine is used to reverse the effects of certain drugs or substances that interfere with this nerve-muscle communication. Such substances include atropine, scopolamine, belladonna, antihistamines, some antidepressants, and other anticholinergic drugs
Typical Symptoms of ANTICHOLINERGIC TOXIDROME = “Mad as a Hatter” (confused), “Dry as a Bone” (dry mouth, urinary retention), Tachycardia, Shaking/Tremosd, Blind as a Bat (dilated pupils (mydriasis), “HOT as a Desert” Hyperthermia, “Red as a Beet” (flushed skin)………..so Physostigmine can be used to reverse this…..
Side effects of Physostigmine would then be the reverse of ANTICHOLINERGIC symptoms, like excessive sweating, vomiting , diarrhea…..ect…
It’s a drug of choice to reverse the effects of TCA overdoses, possibly Antihistamine OD, or too much Atropine (conversely high dose Atropine is Tx for SLUDGE symptoms related to Organophosphate poisoning (which blocks AChEsterase, therefore TOO MUCH Ach)
How is Succ reversed ?
XXX
Not generally reversed due to many complications - - - but some info related to Malignant Hyperthermia
Usually you just use supportive care (keep ventilating) as the duration of action is 10-15 min only.
