Monitored anesthesia care (MAC) sedation: clinical utility of fospropofol

Abstract

Fospropofol, a phosphorylated prodrug version of the popular induction agent propofol, is hydrolyzed in vivo to release active propofol, formaldehyde, and phosphate. Pharmacodynamic studies show fospropofol provides clinically useful sedation and EEG/bispectral index suppression while causing significantly less respiratory depression than propofol. Pain at the injection site, a common complaint with propofol, was not reported with fospropofol; the major patient complaint was transitory perianal itching during the drug's administration. Although many clinicians believe fospropofol can safely be given by a registered nurse, the FDA mandated that fospropofol, like propofol, must be used only in the presence of a trained anesthesia provider.

Keywords: fospropofol; monitored anesthesia care; propofol.

Figure 1

The conversion of fospropofol into its metabolites. Reproduced with permission from Gibiansky E, Struys M, Gibiansky L, Vanluchene A, et al. Aquavan^® injection, a water-soluble prodrug of propofol, as a bolus injection: a phase I dose-escalation comparison with Diprivan^® (Part 1 – Pharmacokinetics). Anesthesiology. 2005;103:718–729. Copyright © 2002 Wolters Kluwer Health.

Figure 2

Some investigators suggest that fospropofol exists in a single peripheral compartment, thereby resulting in a 5-compartment model. Others postulate a dual peripheral compartment for fospropofol, suggesting a 6-compartment model (shown).