Understanding Anesthesiology - The Global Regional Anesthesia ...

FENTANYL
Class
Synthetic opioid analgesic (intermediate-acting); adjunct
to anesthesia. Fentanyl can be used as an additive to spinal
and epidural anesthesia/analgesia.
Mechanism of Action
Acts at the mu-and kappa opioid receptors.
Dose
General anesthesia: 1-20 ug/kg IV according to physical
status, other agents used, duration and nature of surgery.
support their circulation such as those in hypovolemic or
cardiogenic shock.
Respiratory
Respiratory depression which at the extreme leads to apnea.
GI
Nausea, vomiting, biliary tract spasm, constipation.
Misc
Muscle rigidity
Onset
IV 4-6 minutes
Duration
IV 30-45 minutes
Elimination
Hepatic
Effects
CNS
Potent analgesic effects; some sedative effect. Rarely
causes blurred vision, seizures. All of the depressant effects
of fentanyl are potentiated by concurrent use of
sedatives, volatile anesthetics and nitrous oxide.
CVS
Hypotension, bradycardia. 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
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