Simple Technology Makes the World Go Round (Revised)

For my equipment review, I am going to discuss what a lot of people don’t talk about or even notice unless it’s broken – the thermometer. To most people, a thermometer is what you use when a child is sick and you need to know if they are running a fever. For veterinary technicians, it is a vital detecting tool. An animal running hot is often the first sign that something in their body is wrong. So it makes sense that vet techs need good, reliable, accurate thermometers in order to do their job effectively. Monitoring temperature is also useful when a pregnant female is about to give birth. The mother’s temp drops about 24 hours before she starts giving birth. This gives the owners time to prepare for the birthing.

First of all, there are 3 types of thermometers. The old school style is the mercury thermometer, in use since 1714 and the only way of taking temperatures for 350 years. It contains a small bulb of mercury at the bottom of a narrow shaft enclosed within the thermometer’s outer glass structure. The mercury reacts with temperature changes by moving up or down the shaft. Numbers printed on the outside correspond with mercury levels to give the temperature.

The most commonly used thermometer today is the digital thermometer, which uses a thermistor apparatus to measure electrical resistance and translates that into a readable temperature on the digital screen.

And last but not least is the fairly recent aural thermometer. These ear thermometers use remote sensing to detect the infrared radiation, also known as heat radiation, emanating from the eardrum.

Each has its pros and cons and is used differently.

Mercury and digital thermometers are used rectally, meaning that the thermometer goes up the animal’s poop chute. This may gross a lot of people out, but it’s done that way for a reason. Core body temperature is different from surface body temperature. What’s on the outside isn’t necessarily the same on the inside, and in this case, core body temp is more accurate. And in order to get a core body temp, vet techs have to go where a lot of people don’t want to go since pets don’t sit still enough for the thermometer to go under their tongues. Plus, there is an added risk that the animal may bite the thermometer or even swallow it when vet techs try to use it under the tongue.

 

‍One thermometer has to be used on many animals a day. This brings up the problem of disease control. We certainly don’t want to take a rectal temp on one animal, then turn around and use the same thermometer on another animal without some sort of sanitation process. As it turns out, this is relatively simple. Alcohol wipes are extremely effective at killing residual bacteria on the thermometer and sanitizing it for the next patient. Soap and warm water are also efficient antiseptics, but because of the fast-paced nature of most clinics and shelters, alcohol wipes are preferred and just as effective.

Mercury thermometers are considered pretty old fashioned in modern clinics since the results take longer to collect and because they contain mercury, a toxic compound. Digital thermometers can get an accurate temp in as little as one second. When animals don’t like you touching them, much less trying to take a rectal temp, faster is definitely better.

Aural thermometers are a little nicer than rectal thermometers since they take temperatures in the ear instead of the rectum. Easier accessibility to a core body structure and more comfort for the animal, all rolled up in one nice little package. Cons for this one are that aural temps tend to not be as accurate as digital rectal temps, and that vet techs have to be very careful not to touch or puncture the animal’s eardrum. Aural thermometers also tend to eat batteries, making it hard for them to be cost productive.

Overall, just from past experience, and for the reasons listed above, I tend to use digital thermometers since they are just as fast as aural thermometers and more accurate, but less expensive to buy and to run.

Normal companion animal temp range

On a side note, animal temperatures are a little different from human temps. Normal for a pet is between 100 and 103 degree F. Above 103 means the animal is running a fever. Below 100 means the animals is suffering from hypothermia. This info seems trivial, but is crucial considering that a normal adult human temperature is 98 degrees F and normal adult companion animal temperature is 102 degrees F.