So how do you measure someone’s body temperature?
We have six common ways in medicine
that will measure body temperature.
The first is via the axilla. So this is something where
you’re putting a temperature probe in someone’s armpit.
The nice thing about it, it’s very easy to do.
All you have to have is a surface skin available.
The down side of it, is that it’s not very accurate.
So it is simply going to be used very sparingly
and only when you don’t have access to another side.
Blood temperature is another one that we can measure.
This one is very accurate. But the only problem is
you need have an indwelling catheter in place.
So this is usually done in emergency medicine
conditions, or in the ICU, or in clinical care unit.
Esophageal temperature is a very accurate
way to measure body temperature.
And this is done by inserting a temperature probe up
the nose and swallowed down to the height of the aorta.
So you need to have someone who is awake and
fairly motivated to be able to get the temperature
probe in that location. But it is
very accurate if it can be obtained.
Oral temperature is done quite often. And this
is done in many, many clinical situations.
So this is a temperature probe, that’s placed in
the sublingual focused, which is just below the tongue.
And the only downside for this, is it needs
to have low ventilation at this prime point.
Because the more breathing rate that you have,
the more you can cool off the oral tissues,
and therefore, decrease body temperature.
The other thing to think about is that almost
always resolve to a lower body temperature.
Then you would get from some body other
mechanisms, such as blood temperature
or esophageal temperature. It’s usually all about
0,4° less. And thats something to keep in mind
when you’re trying determine someone has a fever.
Rectal temperature is another way you can
measure a body temperature. And this is
often times done in children. And it is for a rectal
temperature is usually a thermometer that is used.
And for this, the only downside with it, is that
the temperature changes that occur in the rectum
are usually slower than a temperature changes
that occur in the blood or in the esophagus
and as because there’s less amount
in the blood flow in the GI system.
The final temperature measurement that people
often times use is a tympanic membrane temperature.
So this involves an infrared temperature
that you try to bounce off a tympanic membrane.
And this enteric could be accurate. The problem is,
is that it’s very hard to bounce this wave right of
the tympanic membrane. Usually, it bounce it
off the external auditory meatus or the
internal auditory meatus. And therefore, you
don’t exactly get tympanic membrane temperature.
And if this is the case, then that temperature
measurement can be inaccurate. Also, even if
you get an accurate temperature measurement
or bounced it off in tympanic membrane,
it usually has a little bit lower than even oral temperature.
And so that’s needs to be taken in to a count.
These are six ways to measure internal temperature.
And again, if available, the blood is the best
followed by the esophageal. And then, if
you’re okay with stable temperature, rectal works
really well. And then, oral temperature, followed by
tympanic membrane temperature. And finally, if it’s
the only thing available, axillary temperature.
Now, when we classify someone in different body
temperatures, we need to think about,
what is a normal body temperature?
So we need to account for a diurnal variation
of a round, a half a degree from 37.
So that be 36,5 to 37,5.
We also if there of a woman of reproductive years, we need
to also change, what is a normal body temperature,
depending upon which phase of their
menstrual cycle the woman is in.
So normally, we think of body temperature as
somewhere between 36,5 and 37,5 °C.
If someone has a low-grade fever,
we use classify that as 37,8 to 38,3 °C.
A high-grade temperature is something
between 39,4 to 40 °C.
Finally, hyperpyrexia is a very dangerous condition
which you can even involve some neurological damage.
This is with temperatures above 41,1 °C.