Common General Anesthetics Given at an Early Age May Cause Brain Damage, Other Neurologic Problems
For immediate release.
NEWS RELEASE NR-03-03For more information, please call Joe Carey (SfN) at (202) 745-5138 or Jim Dryden (WU) at (314) 286-0110 or Bob Beard (UVA) at (434) 924-9641.
COMMON GENERAL ANESTHETICS GIVEN AT AN EARLY AGE MAY CAUSE BRAIN DAMAGE, OTHER NEUROLOGIC PROBLEMS
WASHINGTON, DC February 10 - A combination of drugs commonly used to sedate children undergoing surgery caused widespread brain damage and subsequent functional and learning impairments in rats, researchers say. They caution that more research must be done to determine the relevance of these findings to humans.
Previous animal research has shown that rats given general anesthetics that exert their effects by blocking two different chemical pathways can trick brain cells into committing suicide.
In the new study, infant rats were anesthetized for six hours by an administration of the drugs midazolam, nitrous oxide and isoflurane. “These animals tolerated the anesthesia very well and displayed no obvious neurologic deficits, but when we examined their brains, we saw unmistakable evidence of cell death involving many different brain regions,” says lead author Vesna Jevtovic-Todorovic, MD, PhD, associate professor of anesthesiology at the University of Virginia. “Furthermore, when these rats grew to adulthood, they displayed significant, albeit subtle, learning and memory deficits.”
The research, funded by the National Institutes of Health, is published in the February 1 issue of The Journal of Neuroscience.
Additional investigations showed the rats also displayed disturbances in the circuitry of the hippocampus, a brain region that plays an important role in learning and memory.
“Another class of anesthetic agents called opiates may not have the same central nervous system effects,” says Jevtovic-Todorovic. “However, it’s hard to know whether the effects of the drugs we studied in immature rats would be the same in human infants.”
“The primary goal of anesthesia is to provide safe conditions for painless surgery,” says James Eisenach, MD, of Wake Forest University. Eisenach, an anesthesiologist not involved with the study, explains “If the drugs we use are the best for that purpose, we should not hesitate to use them until we know that they cause problems and we can turn to alternatives that are problem-free. If surgery is not absolutely necessary in infants it should not be performed. This is current medical practice.”
Jevtovic-Todorovic’s colleagues in this study include: Richard Hartman, PhD; Yukitoshi Izumi, MD, PhD; John Olney, MD; Nicholas Benshoff; Krikor Dikranian, MD, PhD; Charles Zorumski, MD; and David Wozniak, PhD, all of Washington University, St. Louis. Jevtovic-Todorovic, Hartman, Izumi, Dikranian, Zorumski, Olney and Wozniak are members of the Society for Neuroscience, which publishes The Journal of Neuroscience. SfN is an organization of more than 31,000 basic scientists and clinicians who study the brain and nervous system.