Neurotoxicity of Anesthetic Agents in Children

To the Editor: The review article (1) about anesthetic agents in use in the pediatric population can be complimented on many topics: it invites the anesthetic community to work with the FDA on anesthetic agents in use in young children, and it reviews the current literature without being too judgmental. However, I strongly advise any future research in this area to control for some very important factors: When using high doses of anesthetics in any animal population, vital signs, pulse oximetry, and ABG analysis are critical. In reviewing many of the papers quoted, the researchers usually gave high doses of agents without assessing significant confounding variables: hypoxia, hypotension, and hypercarbia. All of these can significantly affect neuroapoptosis. As with any toxicity research, using doses in excess of clinically relevant levels is misleading. Just do the same study with two common, but necessary compounds: water and oxygen. It is scientifically invalid to state that since 100 L/kg IV water is lethal, that 1 mL/kg IV water is risky. Or that breathing 21% oxygen is one-fifth as risky as breathing 100%. Neurotoxicity in the infant and child has to be studied with much more control and thought. I encourage dialogue between the FDA and the anesthesia community, but I hope that the editorial boards of medical journals will be more cognizant of the controls necessary in toxicity research. Richard Rowe, MD, MPH Department of Anesthesiology Children's Hospital and Research Center at Oakland Oakland, CA