Corona, Hypoxia and Oximeter: A context to curriculum

Corona, Hypoxia and Oximeter: A context to curriculum

Today few municipal people came to my place to check the oxygen level of people aged above 40 with a device known as an oximeter.
Then I searched and read about it. I have understood a few things which is something that we actually know since school, just need to join the dots!

Revisiting the Basics
Let’s start with our respiratory system.
We inhale air which gets transported to our lungs. This air reaches alveoli which are tiny air chambers (one cell thick). A network of blood capillaries surrounds the walls of the alveolus. Gaseous diffusion takes place and oxygen is carried by RBCs in the form of oxyhemoglobin. This is taken to each tissue and then to each cell where it is utilized to produce energy. The carbon dioxide formed in the process is transported to lungs in the form of either bicarbonate or as carbaminohemoglobin which is then released as carbon dioxide during exhalation.

Hypoxia and Asphyxia
Hypoxia is caused when there is a deficiency of oxygen, whereas, asphyxiation is caused by the accumulation of carbon dioxide along with a diminished supply of oxygen.

Hypoxia and corona
How is corona affecting the biological system?
It messes with this respiratory system wherein the body experiences hypoxia leading to further complications

Early detection of hypoxia with Oximeter
An oximeter is a small device based on the principles of spectroscopy which looks like a stapler. A finger is to be placed inside and light is passed through the fingertip. Oxygenated blood absorbs some light and the rest is transmitted to the detector in the device. We can back-calculate the amount that has been absorbed and correlate with oxygen saturation in the blood.

Knowing the level of oxygenated blood provides an early assessment of whether the person’s oxygen level in the body is dropping enabling doctors to take early measures before condition worsens.

Prevention is better than cure

  1. Maintain hygiene
  2. Social distance is the key
  3. Watch your breath
  4. Be aware about hypoxia which could prevent further complications
  5. Maintain a positive mindset
  6. Don’t panic, but be careful
  7. Take care :innocent:

Researchers increasingly opine that stool swabs might be more reliable, with detection in asymptomatic persons.
What is the opinion of cubists?


@Priti_Kanade Good to see this post.

One week ago SPO2 data collection for all family members also happened at my home town (Dr. Ambedkar Nagar (MHOW) District: Indore, MP) by the Anganwadi Kendra workers. I think this is happening across the country. They came up with a Pulse Oxymeter and hand sanitizer.

Here is captured snap of that process.

This also triggered my curiosity to read about SPO2 and also designing DIY Pulse Oxymeter with IoT enabled.

I have also curated a brief note on SPO2 and would like to add some points here.

Starting With Red Blood Cell (RBC)

RBC also known as Erythrocyte in medical term where Erythro is Red and cyte is cell.

Hemoglobin is a red color pigment and there are millions of hemoglobin molecules in RBC. Each of Hemoglobin can carry four molecules of oxygen.

Oxyhemoglobin : Hemoglobin with oxygen.
Deoxyhemoglobin: Hemoglobin without oxygen.

If every single hemoglobin molecule is completely full of oxygen molecules then blood is said to be 100 % saturated.

If every single hemoglobin molecule is partially full of oxygen molecules then the oxygen saturation is averaged.

Thus this lead to massively important question,

How much oxygen is in your arterial blood?

Deficiency of Oxygen

Deficiency in the amount of oxygen in hemoglobin will led to Hypoxaemia.

where Hypo is low and aemia is in the blood.

The purpose of the red blood cells and the hemoglobin is to carry the oxygen to the tissues and this tissues could be fingers, nose, tongue, kidney, brain etc.
They all need oxygen and If they don’t get enough oxygen that causes Hypoxia .


Hypoxaemia --------------------------> Hypoxia

Hypoxaemia = Defficiency of oxygen in blood.
Hypoxia = Defficiency of oxygen in tissues.

Thus Hypoxia will lead to tissue damage. If there is not enough oxygen to brain, brain may stop working and person may become unconscious and hypoxia can also cause permanent brain damage.

SPO2 is know as saturation of peripheral oxygen. Measuring the SPO2 gives us the oxygen level in blood in percentage.

Range of SPO2 Readings

Normal: 94% to 99%
Need oxygen support: 90% to 95%
Serious illness: <= 88%

We can discuss more on the above range of SPO2 measurement.

Would also like to hear from other users on this platform.

Happy Curiosity and Research !


The blood of a normal person contains about 15grams of Haemoglobin per 100mL of Blood.
Each gram of Haemoglobin has the capacity to carry or bind with 1.34mL of Oxygen.

Which means that 15grams of Haemoglobin will carry 15 x 1.34 = 20.1mL of Oxygen dissolved in 100mL of Blood.

How much oxygen is in your arterial blood?
The total quantity of oxygen bound with haemoglobin in normal arterial blood circulation is 19.4mL where the haemoglobin is 97% saturated.


@Ashish_Pardeshi @drishtantmkawale
That was quite informative
Kindly share references for further reading


Some apps use the phone camera to measure blood oxygen levels. Galaxy S10 had a sensor too.

PhonePulseOximeter-tomlinson2017.pdf (621.2 KB)


Actually I have the physiology of Haemoglobin in my College’s Second Semester and I had read this from Chapter 41-Transport of Oxygen and Carbon Dioxide
in Blood and Tissue Fluids
from Guyton and Hall Textbook of Medical Physiology 13th Edition.