Intrathecal lipophilic opioids as adjuncts to surgical spinal anesthesia

Abstract

Background and objectives: Lipophilic opioids, especially fentanyl and sufentanil, are increasingly being administered intrathecally as adjuncts to spinal anesthesia. This review analyzes the efficacy of these opioids for subarachnoid anesthesia.

Methods: Medline search of the literature from 1980 to the present and a survey of recent meeting abstracts are reviewed.

Results: A significant number of citations regarding intrathecal lipophilic opioids as adjuncts to spinal anesthesia were found: 59 are cited in this review. Most clinical experience has been in obstetric surgery, but lipophilic spinal opioid administration is being used with greater frequency for other surgical procedures as well. The benefits include reduction of minimal alveolar concentration (MAC) when general anesthesia is combined with spinal anesthesia and enhancement of the quality of spinal anesthesia without prolongation of motor block. Intrathecal fentanyl and sufentanil allow clinicians to use smaller doses of spinal local anesthetic, yet still provide excellent anesthesia for surgical procedures. Furthermore, lipophilic opioid/local anesthetic combination permits more rapid motor recovery; short outpatient procedures are therefore more amenable to spinal anesthesia. Finally, the side-effect profiles of intrathecal lipophilic opioids are now well characterized and appear less troublesome than intrathecal morphine.

Conclusions: The anesthesia-enhancing properties and side-effect profile of lipophilic opioids administered intrathecally suggest significant roles for these agents as adjuncts to spinal anesthesia for obstetric and outpatient procedures.