1.32 Rocuronium + Sugammadex

Question 1

Compare and Contrast Roc and Vec

related to clinical applications

Answer 1

Class
both Monoquaternaty aminosteroid

Presentation
VEC Lipophilized- white powder
ROC Clear Colourless solution

Dose / Speed onset

VEC
0.1mg/kg = 2min

ROC

0. 6mg/kg 2-3min
1. 2 mg/kg <1m

Duration of action
Both 20-35min

Question 2

Compare and Contrast Roc and Vec

Answer 2

Relative potency
VEC - 1
Roc 0.15

VD
Both 0.2L/KG

Protein bind
Vec - 60-90%
Roc - 30%

Metabolism
Vec: Hepatic-active metabolites

Roc - Nil

Question 3

Compare and Contrast Roc and Vec

Answer 3

Excretion
Vec:
25% unmetabolized in Urine
20% unmetabolized in Bile

Roc:
40% unmetabolized in bile
15% unmetab in urine

Clearance
Vec 3-6.4mL/Kg/Min

3.9ml/kg/min

Effect of increase dose
Vec Increase duration
Roc Increase speed onset

Question 4

Compare Roc and Vec

Answer 4

Roc is monoquaternary derivative of Vec

Speed onset inversely proportional to potency
Low potency - faster speed onset
d/t relative increase in number drug molecules required produce same clinical effect

Rocs lower potency and lower plasma bind allows more rapid access to NMJ
increase dose - explains possible to achieve rapid onset NMB more effectively vs Vec

Duration of action - related to ligand receptor binding affinity
avidly bound ligand produce clinical effects longer than one that easily dissociates

Question 5

Reversal of Rocuronium

Answer 5

Competitive agonism of normaly physiological mechanism
or Chelation methods

Termination of effect follow bolus NDMB
due to diffusion of drug away from NMJ
Reducing number pre and post synaptic rec blocked

Question 6

Competition reversal Roc

Answer 6

Infusion of neostigmine precent breakdown of ACh
= increase probability of Ach Displacing a NDMB
triggering excitatory post synaptic potential

Works by reversibly complexing w/ esteratic site ACh-esterase

Given w/ Glycopyrrolate
attenuate muscarinic affects caused by XS Ach accum
M2 - Brady
M3 excess Gi Secretions

Onset 4-6 min after admin
Glycoo given as onset and duration similar

Atropine
Initial tachy late brady
faster speed onset / shorter duration

Question 7

Roc Reversal Chelation

Answer 7

Sugammadex (Bridion ^r)

Selective relaxant binding agonist SRBA

Modified y-cyclodextrin
Contains high density negative charge to attract positive amino moieties within NDMB

High affinity bond renders roc inactive
cleared renally without hepatic metabolism

Question 8

Roc reversal dose and evidence

Answer 8

Most studies have investigated reversal
reversal effects on vec and pan are documented
usual dose 4mg/kg

Found produce reversal rapidly @16mg.kg
1.3-1.8min
following RSI w/ 1.2 mg kg

Cochrane review
More effective at reveral of NDMB with lower s/e
Reports of anaphylaxis + prolonged QT documented

Theoretical late release possible
other positive charged drug displace roc
/
patient with reduced renal clearance

Repeat anaesthesia <24h require non aminosteroid relaxation