Lecture 15 NMBD Reversal Agents (Exam IV) -Grayson's Deck Flashcards
How long, generally, until NMJ blockade is fully reversed with neostigmine?
20-30 min
Do AChE inhibitors work with deep neuromuscular blockade?
No
Reversal of NMJ blockade is dependent on these 5 factors:
- Depth of block
- Drug choice (neo vs edro)
- Dose
- Rate of plasma clearance
- Anesthetic agent and depth
What is the max dosage of neostigmine?
40 - 70 mcg/kg
0.04 - 0.07 mg/kg
What is the onset and duration of neostigmine?
Onset: 5 - 10 min
Duration: 60 min
What is the dosage of edrophonium?
1 mg/kg
What is the onset and duration of edrophonium?
Onset: 1-2 min
Duration: 5-15 min
What percentage of neostigmine is renally excreted?
50%
What percentage of both pyridostigmine and edrophonium are renally excreted?
75%
How are NMB reversal agents cleared if the patient has no innate renal function?
30 - 50% cleared hepatically
What is the major side effect of NMBD reversal agents?
↑PSNS activity (from increased nACh and mACh activity)
What drugs would be coupled with NMBD reversal agents to prevent adverse side effects from these drugs?
Anti-cholinergic / Anti-muscarinics
- Atropine
- Glycopyrrolate
If you’re concerned about someone’s cardiac status due to existing disease, which Anticholinergic drug would you use?
Glycopyrrolate
What AChE inhibitor is glycopyrrolate used with?
- Neostigmine
- Pyridostigmine
What NMBD(s) is atropine used with?
Edrophonium
What is the dose of Atropine?
7 - 10 mcg/kg
What common side effects are seen right after atropine administration?
- Mydriasis
- Tachycardia
What is the dose of glycopyrrolate?
What is the max dose?
- 7 - 15 mcg/kg
- 1mg max dose
How long does glycopyrrolate need to be administered over?
2 - 5 min
What reversal drug is specific to mivacurium?
Purified human plasma cholinesterase
What reversal drug is specific to gantacurium?
Cystiene
What reversal drug is very specific to rocuronium?
Sugammadex
What type of drug is sugammadex?
Selective relaxant-binding agent
What should be known about sugammadex’s organic structure and physical properties?
- γ-cyclodextrin
- Dextrose units from starch
- Very H₂O-soluble
What is the MOA of Sugammadex?
Encapsulates rocuronium via:
- Van der Waals forces
- H-bonds
- Hydrophobic interactions
What drugs does sugammadex work with?
Roc > Vec > Pancuronium
What is the E ½ time of sugammadex?
2 hours
How is sugammedex eliminated?
Urine:
- 70% gone in 6 hours
- 90% gone in 24 hours
Differentiate a moderate block vs a deep block.
- Moderate: 2/4 twitches on TOF
- Deep: No twitches to TOF, but will have a twitch w/ post tetanic stimulation
What is the Sugammadex dose for a moderate block?
2 mg/kg
What is the Sugammadex dose for a deep block?
4 mg/kg
What is the sugammadex dose for an extreme (overdose) block?
8 - 16 mg/kg
What are the side effects of Sugammadex?
- Bradycardia
- dose-related N/V
- dose-related Pruritis
- dose-related Urticaria
- Anaphylaxis
If 1.2 mg/kg of rocuronium needs to be re-administered after reversal with sugammedex. What is the minimum waiting time?
5 min
If 0.6 mg/kg of rocuronium needs to be re-administered after reversal with sugammedex. What is the minimum waiting time?
4 hours
If 0.1 mg/kg of vecuronium needs to be re-administered after reversal with sugammedex. What is the minimum waiting time?
4 hours
What drugs/conditions are relative contraindications to sugammadex?
- Contraceptives
- Toremifene (displaces roc from sugammadex)
- Coagulopathy (↑ bleeding)
What is recurarization?
Resumption of NMJ blockade after period of reversal
What s/s would indicated recurarization?
Say you just brought the patient to PACU.
- ↓ SpO₂
- ↓ respiratory effort
- Floppy/uncoordinated
- Unresponsive
What drug and dose would be a good choice for a recurarizing patient in the PACU?
Why might this be a good choice?
- Neostigmine 0.05 mg/kg IV
- Longer duration of action
