Understanding Anesthesiology - The Global Regional Anesthesia ...

Remifentanil
Class
Synthetic opioid analgesic (ultra short-acting); adjunct to anesthesia.
Mechanism of Action
Acts at the mu-and kappa opioid receptors.
Dose
On induction of general anesthesia: 0.3-1 ug/kg
For maintenance of general anesthesia: 0.1-1 $g/kg/minute (by infusion)
For sedation: infusion 0.05 – 0.1 $g/kg/minute
Onset
After single bolus: 1-1.5 minutes
After initiation of infusion: 3-5 minutes
Duration
5-10 minutes; context sensitive half time 3 minutes
Elimination
Non-specific blood-tissue esterases (end-organ independent)
Effects
CNS
Potent analgesic effects, sedation. “MAC sparing” allows up to 75% reduction in dose of coanesthetics.
All of the depressant effects of remifentanil are potentiated by concurrent use of
sedatives, volatile anesthetics and nitrous oxide.
CVS
Exaggerated bradycardia, hypotension (compared with other opioids). The synthetic opioids
are not direct myocardial depressants but they do reduce sympathetic drive, which may result
in decreased cardiac output in patients who are relying on sympathetic tone to support
their circulation, such as those in hypovolemic or cardiogenic shock.
Respiratory
Profound respiratory depressant which often leads to apnea.
GI
Nausea, vomiting.
Misc.
Can cause profound muscle rigidity. Not suitable for spinal or epidural use due to glycine
additive. Rapid elimination requires initiation of post-operative analgesia (usually morphine)
prior to emergence .
Related Glossary Terms
Alfentanil, Analgesia, Apneic threshold, Balanced anesthesia, Continuous Infusion, Fentanyl,
Four A’s of anesthesia, Morphine Sulfate, Naloxone, Opioids, Sufentanil, Total intravenous
anesthesia
Index
Find Term
Chapter 3 - General Anesthesia
Chapter 3 - General Anesthesia
Chapter 6 - Drug Finder
Chapter 6 - Opioid agonists and antagonists