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Caffeine Accelerates Emergence from Isoflurane Anesthesia in Humans: A Randomized, Double-blind, Crossover Study
Robert Fong1, Lingzhi Wang, James P Zacny
1From the Departments of Anesthesia and Critical Care (R.F., L.W., J.P.Z., S.K., J.L.A., Z.X.) Neurobiology (A.P.F.), University of Chicago, Chicago, Illinois the Department of Anesthesia, Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China (L.W.) the Cancer Center (J.P.Z.) the College of Medicine (S.K.), University of Illinois at Chicago, College of Medicine, Chicago, Illinois.
Caffeine significantly speeds up recovery from isoflurane anesthesia in healthy males. This study found that intravenous caffeine reduced anesthesia emergence time by 42% with no adverse effects.
Area of Science:
- Anesthesiology
- Pharmacology
Background:
- No current drugs reverse general anesthesia.
- Previous rodent studies showed caffeine accelerates emergence from anesthesia.
Purpose of the Study:
- To test if caffeine accelerates emergence from isoflurane anesthesia in humans.
Main Methods:
- Randomized, double-blind, crossover study with eight healthy males.
- Subjects received IV caffeine citrate or saline placebo during isoflurane anesthesia.
- Primary outcome: time to emergence after discontinuing isoflurane.
Main Results:
- Caffeine reduced emergence time by 42% (6.9 minutes) compared to placebo (P = 0.002).
- Faster return to baseline Bispectral Index and improved psychomotor testing performance with caffeine.
- No significant differences in vital signs or adverse events.
Conclusions:
- Intravenous caffeine accelerates emergence from isoflurane anesthesia in healthy males.
- Caffeine appears safe for this indication, with no observed adverse effects.
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