Rectal temperature measurement

Rectal Temperature Measurement
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How to take a rectal temperature

Taking a baby's rectal temperature.

A rectal thermometer is the most accurate way to take a temperature.

To take a rectal temperature:

  1. Apply a lubricant jelly or petroleum jelly, such as Vaseline, on the tip of the thermometer so that you can insert it easily.
  2. Choose a quiet place so that the child won't be distracted or move around too much. If you are measuring the temperature of a baby or small child, you can:
    • Place the child faceup with legs bent toward the chest with your hand on the back of the thighs or holding the feet as if you were changing a diaper.
    • Place the child facedown on your lap or on a flat covered or padded surface, such as a bed.
  3. Gently insert the tip of the rectal thermometer about 0.6 in. (1.5 cm) to 1 in. (2.5 cm) into the anal canal. Don't force it into the rectum. Hold the thermometer in place with two fingers close to the anal opening (not near the end of the thermometer).
  4. Leave it there for as long as the instructions say. Time it with a clock or watch. Some thermometers make a beep or other sound when they are ready to read.
  5. Remove the thermometer and read it.
  6. Clean a digital thermometer with cool, soapy water, and rinse it off before putting it away. After a thermometer has been used to take a rectal temperature, do not use it to take an oral temperature.

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The content above contains general health information provided by Healthwise, Incorporated, and reviewed by its medical experts. This content should not replace the advice of your healthcare provider. Not all treatments or services described are offered as services by us. For recommended treatments, please consult your healthcare provider.

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