How to Use a Rectal Thermometer: A Step-by-Step Guide
Taking a temperature is a common practice for monitoring health, especially when you suspect a fever or illness. While oral and axillary (armpit) thermometers are widely used, a rectal thermometer provides the most accurate core body temperature reading. This method is particularly beneficial for infants, young children, and individuals who are unable to hold a thermometer in their mouth reliably. This comprehensive guide will walk you through the process of using a rectal thermometer safely and effectively.
Why Use a Rectal Thermometer?
The rectal method offers several advantages:
* **Accuracy:** Rectal temperature readings are considered the most accurate because they reflect the core body temperature more closely than oral or axillary methods.
* **Reliability:** It’s less susceptible to external factors like breathing through the mouth or recent food/drink consumption.
* **Suitability for Certain Populations:** It’s ideal for infants, young children, people who are unconscious, or those who have difficulty holding a thermometer in their mouth.
When to Use a Rectal Thermometer
Consider using a rectal thermometer in the following situations:
* **Infants and Young Children:** Especially for babies under 3 months, a rectal temperature is often recommended for accuracy.
* **Unconscious or Confused Individuals:** When someone is unable to cooperate with oral temperature taking.
* **When Oral Temperature is Unreliable:** After consuming hot or cold beverages, or if someone breathes primarily through their mouth.
* **Doctor’s Recommendation:** Always follow your doctor’s specific instructions.
What You’ll Need
Before you begin, gather the necessary supplies:
* **Digital Rectal Thermometer:** Use a digital thermometer specifically designed for rectal use. These often have flexible tips.
* **Lubricant:** Petroleum jelly (Vaseline), K-Y Jelly, or another water-soluble lubricant.
* **Clean Gloves (Optional):** For added hygiene.
* **Disinfectant Wipes or Soap and Water:** For cleaning the thermometer before and after use.
* **Tissues or Soft Cloth:** To wipe away excess lubricant.
Step-by-Step Instructions for Taking a Rectal Temperature
Follow these steps carefully to ensure accurate and safe temperature measurement:
1. Prepare the Thermometer
* **Clean the Thermometer:** Before each use, thoroughly clean the thermometer with disinfectant wipes or soap and water. Rinse well and dry with a clean cloth.
* **Turn On the Thermometer:** Press the power button to turn on the thermometer. Ensure the display reads “0.0” or has a similar indication that it’s ready for use.
* **Apply Lubricant:** Generously lubricate the tip of the thermometer with petroleum jelly or another water-soluble lubricant. This will make insertion more comfortable and prevent injury. About 1/2 to 1 inch of lubricant is usually sufficient.
2. Position the Person
The positioning will vary depending on the age and cooperation of the individual.
* **Infants (Under 6 Months):** Place the infant face down across your lap or on a changing table. Hold them securely. You can also position them on their back with their legs bent towards their chest.
* **Older Infants and Toddlers:** Position them face down across your lap or on a changing table. You can also have them lie on their side with their knees bent.
* **Children and Adults:** The person can lie on their side with their knees bent towards their chest. This position provides the best access and comfort.
3. Insert the Thermometer
* **Gently Separate the Buttocks:** Use one hand to gently separate the buttocks to expose the anus.
* **Insert the Thermometer:** With the other hand, gently insert the lubricated tip of the thermometer into the rectum. Insert it only about 1/2 to 1 inch (1.25 to 2.5 cm) for infants and children. For adults, insert it about 1 to 1.5 inches (2.5 to 3.8 cm).
* **Do Not Force It:** If you encounter resistance, do not force the thermometer. Gently reposition it and try again. Forcing it can cause injury.
* **Hold the Thermometer in Place:** Hold the thermometer in place gently but firmly to prevent it from slipping out. Avoid moving the thermometer around while it’s inserted.
4. Wait for the Reading
* **Listen for the Beep:** Most digital thermometers will beep when the reading is complete. This usually takes between 10 seconds and a minute. Consult the thermometer’s instructions for the exact timing.
* **Read the Temperature:** Once the thermometer beeps, carefully remove it from the rectum. Read the temperature displayed on the screen. Note the temperature reading.
5. Clean the Thermometer
* **Clean Thoroughly:** After each use, thoroughly clean the thermometer with disinfectant wipes or soap and water. Rinse well and dry with a clean cloth. This is crucial to prevent the spread of germs.
* **Store Properly:** Store the thermometer in a clean, dry place, away from extreme temperatures or direct sunlight. Consider storing it in its original case or a designated container.
Understanding the Temperature Reading
A normal rectal temperature is generally considered to be between 97.9°F (36.6°C) and 100.4°F (38°C). Keep in mind that temperature can vary slightly depending on the individual and the time of day. A fever is generally defined as a rectal temperature of 100.4°F (38°C) or higher.
* **Normal Range:** 97.9°F (36.6°C) to 100.4°F (38°C)
* **Fever:** 100.4°F (38°C) or higher
**Important Note:** Always consult with a doctor if you are concerned about a fever, especially in infants and young children. A high fever can be a sign of a serious infection.
Safety Precautions
* **Never Leave the Person Unattended:** When taking a rectal temperature, especially with infants and children, never leave them unattended.
* **Use Gentle Insertion:** Always insert the thermometer gently. Never force it.
* **Lubricate Adequately:** Use plenty of lubricant to minimize discomfort and prevent injury.
* **Clean the Thermometer Properly:** Thoroughly clean the thermometer before and after each use to prevent the spread of infection.
* **Use a Rectal Thermometer Specifically:** Do not use an oral thermometer for rectal use.
* **Consult a Doctor:** If you are unsure about the proper technique or have any concerns, consult a healthcare professional.
* **Do not use on individuals with rectal problems:** If the individual has hemorrhoids, rectal prolapse, or has undergone rectal surgery, consult a doctor before taking a rectal temperature.
Tips for Success
* **Choose the Right Thermometer:** Select a digital rectal thermometer with a flexible tip for added comfort and safety.
* **Be Prepared:** Gather all necessary supplies before you begin.
* **Stay Calm:** If you are nervous, the person you are taking the temperature of may also become anxious. Remain calm and reassuring.
* **Use Distraction:** For infants and young children, try using a toy or singing a song to distract them during the process.
* **Document the Reading:** Record the date, time, and temperature reading for future reference.
* **Know When to Seek Medical Advice:** Don’t hesitate to contact a doctor if you’re concerned about a fever, especially in infants and young children.
Troubleshooting
* **Difficulty Inserting the Thermometer:** If you encounter resistance, do not force the thermometer. Try repositioning the person or adding more lubricant.
* **Inaccurate Readings:** Ensure the thermometer is properly cleaned and calibrated. Also, make sure you are inserting it correctly and holding it in place until the reading is complete.
* **The Person is Uncomfortable:** Ensure you are using plenty of lubricant and inserting the thermometer gently. Distraction techniques can also help.
Choosing the Right Thermometer
While this guide focuses on digital rectal thermometers, it’s important to understand the different types of thermometers available and their suitability for various situations.
* **Digital Rectal Thermometers:** These are specifically designed for rectal use. They usually have a flexible tip for added comfort and safety and provide a quick and accurate reading.
* **Digital Oral Thermometers:** These are designed for oral use but should *never* be used rectally. They lack the necessary flexibility and shape for safe rectal insertion.
* **Axillary Thermometers (Armpit):** These are placed under the armpit. While less accurate than rectal thermometers, they are a non-invasive option, particularly for older children and adults who can hold their arm still. They are often considered the least accurate method.
* **Tympanic Thermometers (Ear):** These measure temperature in the ear canal. Accuracy can vary depending on proper placement. They are generally not recommended for infants under 6 months.
* **Temporal Artery Thermometers (Forehead):** These measure temperature on the forehead by scanning the temporal artery. They are non-invasive and generally well-tolerated, but accuracy can vary.
**Why Digital Rectal Thermometers are Preferred for Infants and Young Children:**
The accuracy of rectal thermometers makes them the gold standard for temperature taking in infants and young children. The other methods are often less reliable in this age group.
## Alternatives to Rectal Temperature Taking
While rectal temperature taking is often the most accurate, there are situations where it may not be possible or desirable. Here are some alternative methods and their considerations:
* **Axillary (Armpit) Temperature:**
* **How to:** Place the thermometer high in the armpit, ensuring skin contact. Hold the arm firmly against the body for the recommended time (as per the thermometer instructions).
* **Accuracy:** Less accurate than rectal. Add 1 degree Fahrenheit (0.5 degrees Celsius) to the reading to estimate the core temperature.
* **Suitable for:** Older children and adults who can hold their arm still.
* **Oral Temperature:**
* **How to:** Place the thermometer under the tongue and close the mouth. Breathe through the nose. Avoid eating or drinking for at least 15 minutes before taking the temperature.
* **Accuracy:** Can be affected by recent food or drink consumption and breathing through the mouth.
* **Suitable for:** Children over 4 years old and adults who can cooperate.
* **Tympanic (Ear) Temperature:**
* **How to:** Gently pull the ear back and up (for adults) or back and down (for children under 3) to straighten the ear canal. Insert the thermometer probe into the ear canal and press the button.
* **Accuracy:** Accuracy depends on proper technique. Not recommended for infants under 6 months.
* **Suitable for:** Older children and adults.
* **Temporal Artery (Forehead) Temperature:**
* **How to:** Gently swipe the thermometer across the forehead, following the manufacturer’s instructions.
* **Accuracy:** Can be affected by sweat or environmental factors.
* **Suitable for:** All ages, but accuracy can vary.
**When to Choose an Alternative:**
* **Refusal:** If the person strongly resists rectal temperature taking.
* **Rectal Issues:** If the person has hemorrhoids, rectal fissures, or has had recent rectal surgery.
* **Practicality:** In situations where rectal temperature taking is not feasible.
**Important Considerations for Alternative Methods:**
* Always follow the manufacturer’s instructions for the specific thermometer you are using.
* Be aware that alternative methods may be less accurate than rectal temperature taking.
* Consider the age and cooperation level of the person when choosing a method.
## When to See a Doctor
While taking a temperature can provide valuable information, it’s crucial to know when to seek medical attention. Contact a doctor immediately if:
* **Infants under 3 months:** Have a rectal temperature of 100.4°F (38°C) or higher.
* **Children 3 months to 3 years:** Have a rectal temperature of 102°F (38.9°C) or higher.
* **Adults:** Have a temperature of 103°F (39.4°C) or higher.
* **Any age:** If the fever is accompanied by other concerning symptoms, such as:
* Difficulty breathing
* Stiff neck
* Severe headache
* Rash
* Seizures
* Lethargy or unresponsiveness
* Dehydration
* Persistent vomiting or diarrhea
* Pain that doesn’t improve with medication
**Trust Your Instincts:**
Always trust your instincts. If you are concerned about someone’s health, even if the temperature isn’t extremely high, it’s best to err on the side of caution and seek medical advice.
## Conclusion
Using a rectal thermometer is a safe and accurate way to measure body temperature, especially for infants, young children, and individuals who are unable to take an oral temperature reliably. By following these step-by-step instructions and safety precautions, you can confidently and accurately monitor temperature and seek medical attention when necessary. Remember to always consult with a healthcare professional if you have any questions or concerns about temperature readings or other symptoms.