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 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 (aminosteroid) ?
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
