Onset and effectiveness of rocuronium for rapid onset of paralysis in patients with major burns: priming or large bolus

Br J Anaesth. 2009 Jan;102(1):55-60. doi: 10.1093/bja/aen332. Epub 2008 Nov 21.


Background: Burn injury leads to resistance to the effects of non-depolarizing muscle relaxants. We tested the hypothesis that a larger bolus dose is as effective as priming for rapid onset of paralysis after burns.

Methods: Ninety adults, aged 18-59 yr with 40 (2)% [mean (SE)] burn and 30 (2) days after injury, received rocuronium as a priming dose followed by bolus (0.06+0.94 mg kg(-1)), or single bolus of either 1.0 or 1.5 mg kg(-1). Sixty-one non-burned, receiving 1.0 mg kg(-1) as a primed (0.06+0.94 mg kg(-1)) or full bolus dose, served as controls. Acceleromyography measured the onset times.

Results: Priming when compared with 1.0 mg kg(-1) bolus in burned patients shortened the time to first appearance of twitch depression (30 vs 45 s, P<0.05) and time to maximum twitch inhibition (135 vs 210 s, P<0.05). The onset times between priming and higher bolus dose (1.5 mg kg(-1)) were not different (30 vs 30 s for first twitch depression and 135 vs 135 s for maximal depression, respectively). The onset times in controls, however, were significantly (P<0.05) faster than burns both for priming and for full bolus (15 and 15 s, respectively, for first twitch depression and 75 and 75 s for maximal depression). Priming caused respiratory distress in 10% of patients in both groups. Intubating conditions in burns were significantly better with 1.5 mg kg(-1) than with priming or full 1.0 mg kg(-1) bolus.

Conclusions: A dose of 1.5 mg kg(-1) not only produces an initial onset of paralysis as early as 30 s, which we speculate could be a reasonable onset time for relief of laryngospasm, but also has an onset as fast as priming with superior intubating conditions and no respiratory side-effects.

Publication types

  • Controlled Clinical Trial
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Androstanols / administration & dosage*
  • Androstanols / adverse effects
  • Androstanols / pharmacology
  • Burns / physiopathology*
  • Burns / surgery
  • Dose-Response Relationship, Drug
  • Drug Administration Schedule
  • Female
  • Humans
  • Intubation, Intratracheal
  • Male
  • Middle Aged
  • Neuromuscular Blockade* / adverse effects
  • Neuromuscular Junction / drug effects
  • Neuromuscular Junction / physiopathology
  • Neuromuscular Nondepolarizing Agents / administration & dosage*
  • Neuromuscular Nondepolarizing Agents / adverse effects
  • Neuromuscular Nondepolarizing Agents / pharmacology
  • Prospective Studies
  • Respiratory Insufficiency / chemically induced
  • Rocuronium
  • Time Factors
  • Young Adult


  • Androstanols
  • Neuromuscular Nondepolarizing Agents
  • Rocuronium