Doctors Warn Against Infrared Thermometers

By BARNABY J. FEDER
Over the next month, thousands of high school and college football teams will get ready for fall by practicing in torrid conditions where heatstroke is a constant danger.
That has some trainers and doctors worried about increasingly popular thermometers that, in their view, sacrifice accuracy for convenience.
The devices use infrared light to scan heat radiation in the ear or on the forehead. The infrared thermometers have produced lower readings in athletic settings — or in lab tests meant to simulate them — than rectal thermometers or other devices.
After testing a widely marketed forehead scanner made by Exergen, researchers at the Institute for Exercise and Environmental Medicine at Presbyterian Hospital in Dallas warned that low readings from the device could deprive patients of critical, perhaps lifesaving medical care.
In the test, reported last month in the journal Medicine and Science in Sports and Exercise, the infrared thermometer gave readings below 100 degrees Fahrenheit when rectal thermometers topped 104 degrees, a temperature at which some patients begin to become vulnerable to heatstroke.
Douglas J. Casa, director of athletic training education at the University of Connecticut, who recently completed a study of 10 types of thermometers in intense training situations, said the infrared forehead and ear scanners were among those producing misleadingly low readings in his test.
And Dr. William Roberts, a University of Minnesota researcher and former president of the American College of Sports Medicine, said his tests of the forehead device on runners in the Medtronic Twin Cities Marathon led him to similar conclusions. Both have submitted their results to peer-reviewed journals.
Exergen said that it was apparent from the report on the Texas test, which used healthy subjects in heated wet suits, that the researchers did not duplicate realistic conditions for athletes, or anyone with a fever.
Exergen also pointed out that the thermometer, the Temporal Scanner, was not marketed for use in athletic settings and came with instructions specifically stating that it was not for outdoor use. That goes for both the consumer version, which costs $30 to $50 at drugstores and other chains, and a more durable model sold for about $350 to doctors’ offices and hospitals.
The company Web site includes a 2005 news release noting that its thermometers had been used for 17 years at the Boston Marathon. But Francesco Pompei, the company president, said the release made it clear that the device had required special handling at the marathon.
The changes, including use of a piece of film to deal with perspiration, have been shared with a small number of trainers who sought more information for their own studies, Mr. Pompei said.
“We use sports medicine for research,” he said. “But we are not selling into the athletic market.”
He added that the association with the Boston Marathon, which began in 1989, ended last year with the retirement of Dr. Marvin Adler, longtime medical director of the race.
Critics said the device might attract coaches looking for something simpler than rectal thermometers and less costly than the most accurate devices available outside hospitals, radio-transmitting temperature-sensing pills that athletes swallow.
Mr. Pompei said his company would be glad to work with critics to discourage using the Temporal Scanner in athletic settings.
But a broader battle may loom. Dr. Benjamin D. Levine, a physician who took part in the Dallas test, said the scanner should not be used in any setting, even though 30 percent of Texas hospitals now use it or a similar device.
Novation, a hospital purchasing group, said its members bought more than $1 million worth of them last year and had not heard any complaints.