ROCURONIUM 

1. Introduction

Rocuronium is a non-depolarizing neuromuscular blocking agent (NDNMBA) of the aminosteroid group.


 2. Classification

Class

Drug

Aminosteroid

Rocuronium, Vecuronium, Pancuronium

Benzylisoquinolinium

Atracurium, Cisatracurium

 3. Mechanism of Action

  • Competitive antagonist at nicotinic acetylcholine receptors (Nm) at neuromuscular junction
  • Prevents depolarization flaccid paralysis

Sequence of paralysis:

  1. Small muscles (eyes, face)
  2. Limbs
  3. Intercostals
  4. Diaphragm (last)

Recovery reverse order


4. Pharmacokinetics 

Parameter

Rocuronium

Onset

60–90 sec (fast)

Duration

30–60 min

Metabolism

Minimal hepatic

Elimination

Hepatobiliary (major)

Half-life

60–120 min

 Compared to vecuronium faster onset


 5. Dosing (ICU & RSI)

 RSI Dose

  • 1–1.2 mg/kg IV
    Comparable onset to succinylcholine

 Maintenance / ICU infusion

  • Bolus: 0.1–0.2 mg/kg
  • Infusion: 5–12 µg/kg/min

 6. Indications in ICU

 Airway & Ventilation

  • Rapid sequence intubation 
    • Hyperkalemia risk
    • Burns
    • Neuromuscular disease
  • Severe ARDS ventilator synchrony
  • Status asthmaticus (refractory)
  • Raised ICP (prevents coughing/straining)

 Procedural

  • Central line insertion (rarely)
  • Imaging (MRI/CT if needed)

 7. Rocuronium vs Succinylcholine 

Feature

Rocuronium

Succinylcholine

Type

Non-depolarizing

Depolarizing

Onset

Fast (60–90 sec)

Very fast (30–60 sec)

Duration

Longer (30–60 min)

Short (5–10 min)

Hyperkalemia

 No

 Yes

Malignant hyperthermia

 No

 Yes

Fasciculations

No 

Yes 

 Guideline shift:
Rocuronium increasingly preferred for RSI when sugammadex available


 8. Advantages in Critical Care

  • Hemodynamically stable
  • No histamine release
  • No increase in ICP/IOP
  • Safe in:
    • Burns
    • Neuromuscular disorders
    • Hyperkalemia

 9. Adverse Effects

Common

  • Prolonged paralysis (especially in ICU)
  • ICU-acquired weakness (when prolonged use)

 Rare

  • Anaphylaxis (higher risk among NMBAs )
  • Tachycardia (mild)

10. Contraindications / Caution

  • Severe hepatic dysfunction prolonged action
  • Obesity dose based on ideal body weight (IBW)
  • Myasthenia gravis exaggerated effect

 11. Monitoring in ICU

Train-of-Four (TOF)

  • Target: 1–2 twitches out of 4
  • Prevents over-paralysis

Clinical endpoints

  • Ventilator synchrony
  • Absence of spontaneous breathing

12. Reversal 

 Sugammadex

  • Specific reversal agent for aminosteroid NMBAs
  • Encapsulates rocuronium rapid reversal

Dose

Indication

2 mg/kg

Moderate block

4 mg/kg

Deep block

16 mg/kg

Immediate reversal (RSI)

 Advantage over neostigmine:

  • Faster
  • More predictable
  • No cholinergic side effects