Measuring core temperature, or the internal body temperature, accurately is crucial in certain medical situations, athletics, and work-related environments, among others. The ideal reading varies from person to person, but it usually falls between 97.5°F (36.4°C) and 99.5°F (37.5°C). With that in mind, what is the best way to measure core temperature accurately and safely? Here’s what you need to know.
Rectal Temperature
Rectal temperature is perhaps the most invasive yet most accurate method to measure core temperature. It’s usually done with a digital thermometer lubricated with petroleum jelly and inserted 1-2 inches into the rectum. The patient is then instructed to lie on their side while waiting for the device to beep and record the reading. It’s important to note that rectal temperature is often 0.5-1°F (0.3-0.6°C) higher than oral temperature and that it should only be measured in emergencies, critically ill patients, or when other methods are not accessible.
Oral Temperature
Oral temperature is the most common way to measure body temperature. It’s done by placing a digital thermometer under the tongue, closing the mouth, and waiting for the device to beep the reading. According to medical professionals, oral temperature is a reliable method to measure core temperature, but it also has a slightly lower accuracy rate than rectal temperature. To get the best results, it’s recommended to take the oral temperature before eating, drinking, or smoking.
Axillary Temperature
Axillary temperature is done by placing a thermometer in the armpit and holding the arm against the body for several minutes. It’s the least invasive method to measure core temperature, but it’s also the least accurate. In fact, axillary temperature is 1°F (0.6°C) lower than oral temperature, and it’s usually not used in health care settings unless other methods are impossible.
Ear Temperature
Ear temperature is often done with an infrared thermometer that reads the temperature of the temporal artery located in the forehead. The device is pointed at the ear canal and takes a reading within seconds. This method is quick and non-invasive, making it ideal for children, but it’s also less accurate than oral and rectal temperature. There’s a risk of improper placement, earwax buildup, or ambient temperature affecting the reading, so it’s essential to follow the manufacturer’s instructions carefully.
Skin Temperature
Skin temperature is measured with a digital thermometer that reads the temperature of the skin’s surface. This method is used in athletics and outdoor sports to prevent heat exhaustion and dehydration. It can be done on any part of the body, but it’s usually done on the forehead or neck. Skin temperature is lower than core temperature, and it can vary depending on factors like wind, humidity, and sweating. Nevertheless, it’s a useful tool to monitor body temperature in real-time and prevent overheating.
Ingestible Temperature
Ingestible temperature is measured by swallowing a small pill that contains a telemetry sensor. The sensor transmits a signal to a receiver that displays the core temperature. This method is still under clinical studies, but it shows promise in extreme environments like space, deep-sea diving, or polar expeditions. The main advantage of ingestible temperature is that the sensor stays in the body for up to 30 hours, providing continuous and accurate readings without any discomfort or interruption.
Conclusion
Measuring core temperature accurately is essential to monitor health, prevent illnesses, and perform at peak levels. The best way to measure core temperature depends on the situation, the person’s condition, and the equipment available. Rectal temperature is the most accurate but also the most invasive. Oral temperature is reliable and commonly used, while axillary temperature is less invasive but less accurate. Ear temperature and skin temperature are quick and non-invasive, making them ideal for children and athletics, respectively. Finally, ingestible temperature shows promise in extreme environments but requires more clinical studies to be widely available. Whatever method you choose, it’s important to follow the instructions carefully and note any factors that can affect the reading. By measuring core temperature accurately, you can ensure your body is functioning normally and take action when necessary.