The effect of hot beverages, cold beverages, and chewing gum on oral temperature

Abstract

Background: A prospective blood donor's oral temperature is affected by external stimuli such as drinking a hot or cold beverage or chewing gum. These stimuli can cause a deferral or an inappropriate acceptance for a certain unknown time.

Study design and methods: Ten volunteer subjects were exposed to each of the three stimuli in separate studies. Oral and tympanic membrane temperatures were taken before exposure, immediately after exposure, and at various times until the subject's temperature returned to baseline.

Results: The drinking of a hot beverage caused an immediate mean temperature elevation of 2.6 degrees F which would lead to deferral for 7 of 10 subjects. All subjects were acceptable for blood donation (temperature <99.6 degrees F) by 5 minutes. A cold beverage lowered the temperature; the temperature in 6 subjects returned to baseline by 10 minutes and that in 4 did so by 30 minutes. Gum chewing caused minimal temperature elevations; only 1 donor's temperature reached 99.6 degrees F, and it was at acceptable levels for blood donation by 5 minutes.

Conclusion: Drinking a hot beverage and, to a much lesser degree, gum chewing can lead to a deferral for elevated temperature, but subjects were acceptable by 5 minutes. Cold beverages are of more concern, because they suppress the temperature for a short time and could theoretically lead to acceptance of a febrile, possibly infectious donor.