How to Use a Rectal Thermometer

Rectal temperatures are considered to be the most accurate. However, the digital ear thermometers have gained in popularity, taking over as the thermometer of choice in many emergency rooms.

Instructions

Difficulty: Moderately Easy

Things You’ll Need:

• Isopropyl Alcohols
• Antibacterial Soaps
• Facial Tissues
• Petroleum Jelly
• Rectal Thermometer

1. Shake down the mercury in your rectal thermometer to below the 98 degrees F mark.
2. Check the thermometer under a bright light to make sure the mercury is down.
3. Lubricate the end of the glass thermometer with petroleum jelly.
4. Ask your child to lie on her left side with knees bent or across your lap.
5. Insert the thermometer into the rectum approximately one inch. Never force the thermometer.
6. Ask the child to lie still.
7. Remove the thermometer after two minutes. Use a watch to make sure you have left the thermometer in for the full two minutes. Pulling a thermometer out too early will cause you to miss a fever.
8. Wipe the thermometer off with a tissue. Unless the glass is wiped clean, it is difficult to get an accurate reading.
9. Hold the thermometer under a bright light to get your reading. Take your time. The mercury will not drop, once it has been removed from the rectum.
10. Understand that a normal rectal temperature is 99.6 degrees F.

Tips & Warnings

• Many of the digital ear thermometers have switchable tips, allowing you to use the same thermometer to take rectal temperatures.
• Especially in children, normal temperatures can fluctuate by a degree.
• Avoid taking a rectal temperature immediately after activity, a bowel movement or a hot bath or shower.
• Clean a rectal thermometer in soapy warm water and then wipe it with isopropyl alcohol. Never use water warmer than 97 degrees F.
• Never use a glass oral thermometer in a rectum. The oral tip is slender and easier to break than a rectal thermometer tip.