Learning About Taking Your Child's Temperature

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Electronic and ear thermometers

How do you take a child's temperature?

Body temperature is a measure of how well your child's body can make and get rid of heat. You can find out what your child's temperature is by using a thermometer. There are specific types of thermometers to use in different parts of the body.

A rectal or ear temperature reading is about 0.25°C to 0.5°C higher than an oral reading. A temperature taken in the armpit is about 0.25°C to 0.5°C lower than an oral reading. Rectal thermometers are thought to be the most accurate way to check a child's temperature.

Experts say that a rectal temperature in a child over 38°C is a fever.

The method you use to take a child's temperature depends on the child's age:

  • For a baby or child younger than 2 years, it's best to use a rectal thermometer for an accurate reading. You can also take your child's temperature from his or her armpit (axillary).
  • For a child ages 2 to 5 years, you can use a rectal, armpit, or ear thermometer. But rectal is the most accurate.
  • For a child 5 years or older, use a mouth, armpit, or ear thermometer.

To take a temperature by mouth (orally)

  1. Place the thermometer under the tongue, just to one side of the centre. Have your child close his or her lips tightly around it.
  2. Leave the thermometer in place for the required amount of time.
  3. Remove the thermometer and read it.
  4. Clean the thermometer with cool, soapy water, and rinse it off before you put it away.

To take a rectal temperature

A rectal thermometer is the most accurate way to take a temperature in a child younger than age 5.

  1. Put a lubricant jelly or petroleum jelly, such as Vaseline, on the tip of the thermometer. This will help you insert it easily.
  2. Turn your child face down on your lap or on a flat covered or padded surface, such as a bed.Choose a quiet place so that the child won't be distracted or move around too much.
  3. Spread your child's buttocks apart with one hand. Gently insert the bulb end of the rectal thermometer about 1 to 2.5 centimetres into the rectum with your other hand. Don't force it into the rectum. Hold the thermometer in place with two fingers close to the rectum (not near the end of the thermometer). Pressing the child's buttocks together will help keep the thermometer in place.
  4. Leave the thermometer in place for the required amount of time.
  5. Remove the thermometer and read it.
  6. Clean the 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.

To take an armpit temperature

  1. Place the thermometer under the arm with the tip in the centre of the armpit.
  2. Press the arm against the body, and leave the thermometer in place for the required amount of time.
  3. Remove the thermometer and read it.
  4. Clean the thermometer with cool, soapy water, and rinse it off before putting it away.

To take an ear temperature

  1. Check that the ear probe is clean. If it is dirty, wipe it gently with a clean cloth. Do not put the thermometer in water.
  2. To keep the probe clean, use a disposable probe cover. Attach the disposable cover to the probe.
  3. Turn the thermometer on.
  4. Pull the earlobe up and back. Centre the probe tip in the ear, and push gently inward toward the eardrum.
  5. Press the "on" button to display the temperature reading.
  6. Remove the thermometer, and throw away the used probe cover.
  7. Use a new probe cover each time you take an ear temperature.

Where can you learn more?

Go to https://www.healthwise.net/patientEd

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