Succinylcholine

What is Succinylcholine? 1

  • A depolarizing neuromuscular blocking drug
  • Commonly used for rapid sequence induction and intubation due to its rapid onset and ultra-short duration of action.
  • Succinylcholine has very important contraindications

Mechanism of Action & Pharmacokinetics 1

  • Mimics acetylcholine by binding to nicotinic receptors at the neuromuscular junction, causing an initial depolarization (muscle fasciculations) followed by sustained depolarization, leading to paralysis.
  • Onset of action is typically 30-60 seconds, with peak effect occurring within 1 minute.
  • Duration of action is approximately 5-10 minutes due to rapid hydrolysis by plasma cholinesterase (pseudocholinesterase).

Pharmacodynamics 1

Cardiovascular

  • Minimal direct cardiovascular effects, but may cause bradycardia, particularly in pediatric patients or with repeated dosing.

    Respiratory

  • Causes complete paralysis of respiratory muscles, requiring assisted ventilation until the drug wears off.

    Neurological

  • Can cause increased intracranial pressure (ICP) transiently.

Indications 1

  • DrugLibrary/Rapid Sequence Induction Rapid Sequence Induction Private or Broken Links
    The page you're looking for is either not available or private!
    and intubation.
  • Situations requiring quick onset of muscle paralysis.

Dosage 2

  • Intubation Dose: 1-1.5 mg/kg IV based on total body weight (TBW).
  • Intramuscular Dose: 3-4 mg/kg IM based on total body weight (TBW).

Contraindications 1

  • History of malignant hyperthermia.
  • Hyperkalemia or conditions that predispose to hyperkalemia (e.g., burns, severe trauma, spinal cord injuries).
  • History of myopathies associated with elevated creatine kinase (CK) levels.

Complications 1

  • Bradycardia, especially with repeated doses in pediatric patients.
  • Hyperkalemia
  • Malignant hyperthermia in susceptible individuals.
  • Fasciculations, which can cause postoperative myalgias.

References

  1. Birdi T, Sullivan P. Ottawa Anesthesia Primer. Toronto, Ontario: Echo Book Publishing; 2012.  2 3 4 5 6

  2. De Baerdemaeker LE, Mortier EP, Struys MM. Pharmacokinetics in obese patients. Continuing Education in Anaesthesia Critical Care & Pain. 2004 Oct;4(5):152–5.