Useful medical devices at home: blood pressure monitor, pulse oximeter, thermometer

In a crisis, getting to a doctor is harder, and the question “do I go to hospital or wait?” becomes more important. A few simple medical devices, used correctly, help you keep track of someone who’s unwell, give a doctor concrete readings over the phone and recognize when things are getting serious. They don’t replace a doctor, but they give you information.

The thermometer: essential

Fever is the simplest sign that something is wrong. You need a digital thermometer (oral or underarm) for adults and, if you have small children, an ear or forehead one, which is quicker and easier. Mercury thermometers are banned or phased out in many countries; if you still have one and it breaks, don’t vacuum the mercury or touch it.

The blood pressure monitor

High blood pressure is one of the most common conditions worldwide and often has no symptoms. A home monitor is useful for:

• anyone over 40;
• people treated for blood pressure, to check the treatment is working;
• keeping an eye on an older relative during a crisis.

How to choose: an upper-arm monitor, not a wrist one (wrist monitors are more sensitive to position and less accurate). Check the model is clinically validated and the cuff fits your arm.

How to measure correctly:

1. Sit quietly for 5 minutes beforehand, back supported, feet flat, legs uncrossed.
2. Arm resting on a table at heart level, cuff on bare skin.
3. Don’t talk during the measurement.
4. Take 2 or 3 readings a minute apart and note the average.
5. Measure at the same time, morning and evening, before medication.

The pulse oximeter

A pulse oximeter clips onto a finger and shows blood oxygen saturation (SpO₂) and pulse. It became popular during the pandemic and remains useful for:

• respiratory infections in vulnerable people;
• heart and lung patients;
• monitoring someone ill at home when a doctor isn’t available.

How to read it: usual values are 95 to 100%. Cold hands, nail polish, movement or poor circulation can give false readings, so repeat on another finger with a warm, still hand. Take symptoms into account: breathing difficulty, blue lips or confusion are emergencies, whatever the device says.

The glucose meter

For people with diabetes, a glucose meter is essential, and a reserve of test strips matters as much as a reserve of medicine. For the rest of the family it isn’t needed unless a doctor recommends it.

What isn’t worth it

The market is full of “medical” gadgets: rings that measure everything, anti-snoring devices, machines promising full diagnoses. Many aren’t registered as medical devices. For emergency preparedness, the four above cover almost everything that matters.

How to look after them

• Keep them with the first aid kit.
• Check batteries twice a year and keep spares.
• Write readings in a notebook with the date and time: a doctor will want to see them.

See also the home first aid kit.