Propofol

For exam revision only — verify all doses against the current BNF, the SmPC and your local formulary before clinical use. Disclaimer

Propofol

Intravenous anaesthetic (alkylphenol)

A lipophilic IV agent for induction and maintenance with rapid, smooth onset and offset, used for TIVA/TCI and sedation.

Dose
  • Induction — 1.5-2.5 mg/kg IV, titrated (reduce in the elderly)
  • Maintenance (TCI) — effect-site target 3-6 micrograms/mL
  • ICU sedation — up to 4 mg/kg/h
Indications
  • Induction of anaesthesia
  • Maintenance (TIVA / TCI)
  • Sedation (ICU and procedural)
Cautions
  • Dose-dependent hypotension and apnoea
  • Propofol infusion syndrome with prolonged high-dose use
  • Pain on injection; egg/soya components in the emulsion

Pharmacokinetics

Disposition

Describe the pharmacokinetics of propofol.

A highly lipophilic agent with a large volume of distribution and rapid redistribution.

  • Onset within one arm-brain circulation; offset after a bolus is by redistribution.
  • Volume of distribution is large (~4 L/kg); ~98% protein-bound.
  • Hepatic and significant extra-hepatic metabolism to inactive conjugates, renally excreted.
  • Context-sensitive half-time rises modestly with infusion, allowing predictable TIVA.

Pharmacodynamics

Systemic effects

What are the cardiovascular and respiratory effects of propofol?

Dose-dependent cardiovascular and respiratory depression.

  • Falls in SVR, contractility and preload cause hypotension, marked in the elderly or hypovolaemic.
  • Blunts the baroreflex, so compensatory tachycardia is often absent.
  • Dose-dependent respiratory depression and apnoea; obtunds airway reflexes.
  • Anticonvulsant; reduces CMRO₂, cerebral blood flow and ICP.