Caffeine may help patients wake up more quickly after general anesthesia, an animal study suggests.
Adult rats were given a 3 percent concentration of a general anesthetic for one hour to simulate effects of a brief surgical procedure. During the last 10 minutes of anesthetic exposure, they received an injection of either caffeine or a salt solution (the control group).
The experiment was repeated three times with increasingly higher amounts of caffeine. Each time, rats in the caffeine group woke faster than the others. At the highest dose, the rats in the caffeine group woke up 55 percent sooner than the control group.
The researchers said caffeine appears to shorten anesthesia recovery time in two ways.
Caffeine boosts levels of cyclic adenosine monophosphate (cAMP), a compound that regulates cell function. Previous studies have found an increase in cAMP levels speeds recovery from general anesthesia, the researchers said.
Caffeine also acts as an adenosine receptor antagonist. Nervous system activity slows when adenosine binds to its receptors, causing sleepiness. Caffeine prevents this binding, according to the study authors.
The study, led by University of Chicago researchers, was published online recently in the Journal of Neurophysiology.
It’s important to remember that findings in animal studies frequently fail to produce similar results in humans.
The U.S. National Institute of General Medical Sciences has more on anesthesia.