Core pharmacology

Class Group

Non-Depolarizing
Isoquinolone

Legacy Cicm Level

Level 1

Introduction

Benzylisoquinolinium ester

Indications Uses

to facilitate intubation and controlled ventilation

Chemical Pharmaceutics

Bisquaternary. 1 of 10 stereoisomers. In atrac (15% wt, 50% pot)

Presentation

Clear, 10mg in 5mL as cisatracurium besylate, stored at 4°C.

Mechanism of action

ND-NMB acts as competitive antagonist →
competes with ACh for nAChR binding → blocks cholinergic transmission → muscle
relaxation (> 70% post-synaptic nAChR occupancy required to result in block)
ND-NMB also inhibits pre-synaptic ACh receptors →prevents enhancement of ACh
release → fade with repeated stimulation

Onset Peak Duration

Intubate @ 3 – 5min

Duration 45mins

Adverse Effects Toxicity

HISTAMINE RELEASE
- None
VAGOLYSIS
- None
OTHER
- Anaphylaxis

Protein binding

PB 15%

Volume of distribution

VD 0.15L/kg

Metabolism

77% Hofmann degradation →
laudanosine and quat.
monoacrylates
Minimal ester hydrolysis
Inactive metabolites

Excretion

Ren: 10-30% (laud.)
Liver: (laudanosine)

Clearance

Pl cl 4-5ml/kg/min

Half-life

El t1/2: 25mins

Special Points

Duration prolonged by:
- ↓K ↓Ca ↑Mg
- ↑pH ↑PaCO2
- ↓temp ↓protein Dehydration

Route And Dose

ED95 0.05 mg/kg
Int 0.15 mg/kg

Inf 1 – 2 mcg/kg/min