Vital Signs Home Monitoring Kit

Since getting in to see a doctor these days can be very difficult (for example, we are not going to be seeing patients in person until 2021), now seems like a good time to get a home monitoring kit. For around 200$ you can purchase a set of devices that will measure your blood pressure, heart rate, weight, temperature and blood oxygenation. Quite a miracle of technology, if you think about it.

Blood Pressure and Heart Rate Monitor

A good blood pressure machine is very helpful for assessing a number of conditions, including orthostatic hypotension (dizziness when standing up, that can be caused by many psychiatric medications) and hypertension.

There are several good choices that are reasonably priced. These are the current recommendations from the New York Times’ Wirecutter site.

These are the current recommendations from Consumer Reports.

Due to the COVID-19 pandemic, there has been an increase in use of home blood pressure monitors through telemedicine modalities with self-measured blood pressure (SMBP). The American Medical Association (AMA) created a 7-Step SMBP Quick Guide to help you achieve and maintain blood pressure goals.

Thermometers

Having an accurate thermometer is essential for anyone these days. Wirecutter has several recommendations, but as of this date, most of them were not available.

The good news is that most under the tongue thermometers are reasonably accurate.

For those who prefer the cleanliness and ease of use of an infrared temperature gauge you should know that there is a great deal of variability in the accuracy of these measurements.

Forehead measurements are the least reliable, unless done very carefully. Tympanic membrane (ear drum) measurements are very reliable, unless wax gets in the way. Another option that is quite reliable is measuring the temperature on the neck over the carotid artery (which you can usually see or at least feel, it is where the neck pulse rate is measured).

Pulse Oximeter

Pulse oximeters seem like a very good idea. In theory they can quickly tell you if your lungs are not delivering enough oxygen to your body, and thus screen for significant illnesses, such as CoVID, that may show up with relatively few symptoms but large drops in oxygen in the blood. However, there is a great deal of variability in the accuracy of the devices.

If you want to find accurate devices you can go to the FDA’s website and search for FDA approved pulse oximeters, there are many of them, but then you will spend quite a bit of time searching online to find devices that you can actually purchase.

As a short cut, one device has been shown to be reasonably accurate in studies in two medical journals and is still available to purchase, the CMS50D pulse oximeter. As of late June 2020 it is still available to purchase for around 50$.

Scales

Devices to measure weight are fairly reliable, but body weight measurements can be hard to translate into changes in body fat, which is usually what we care about, because most of what we measure is water (either inside the cell or outside the cell) and many factors (hydration status, edema, etcetera) affect the amount of water in the body, and vary from day to day.

So, a single weight measurement gives us only a rough idea of body fat. However, taking 2 or 3 weight measurements in a period of a week is a pretty good way to track changes in body fat. 

These are the recommended body scales from Wirecutter:

And these are the recommended scales from Consumer Reports:

References:

  1. Lipnick, Michael S. MD; Feiner, John R. MD; Au, Paul BS; Bernstein, Michael BS†; Bickler, Philip E. MD, PhD The Accuracy of 6 Inexpensive Pulse Oximeters Not Cleared by the Food and Drug Administration: The Possible Global Public Health Implications, Anesthesia & Analgesia: August 2016 – Volume 123 – Issue 2 – p 338-345
    doi: 10.1213/ANE.0000000000001300
  2. Ataş Berksoy E, Bağ Ö, Yazici S, Çelik T. Use of noncontact infrared thermography to measure temperature in children in a triage room. Medicine (Baltimore). 2018;97(5):e9737. doi:10.1097/MD.0000000000009737
  3. Gasim GI, Musa IR, Abdien MT, Adam I. Accuracy of tympanic temperature measurement using an infrared tympanic membrane thermometer. BMC Res Notes. 2013;6:194. Published 2013 May 10. doi:10.1186/1756-0500-6-194
  4. American Medical Association. 2020. The 7-step self-measured blood pressure (SMBP) quick guide. [online] Available at: https://www.ama-assn.org/delivering-care/hypertension/7-step-self-measured-blood-pressure-smbp-quick-guide [Accessed 24 May 2021].