8 min

The ongoing pandemic situation holds many mysteries. The second wave of covid 19  in recent times has overwhelmed the healthcare system. The covid cases and death owing to complications of covid is increasing day by day. Many conditions are associated with covid such as black, white, yellow fungus, etc. A new condition called happy hypoxia has been reported in recent times. As the second wave of pandemic rages, young people are now reporting severe lung infections. This is due to happy hypoxia which is a silent killer in recent days. Hence this article highlights the importance of knowing about happy hypoxia.


The decrease in oxygen level in the blood, below 95% is hypoxia. One of the major symptoms of covid 19 is reduced oxygen level. Many of the patients don’t develop any signs (asymptomatic). When checked with a pulse oximeter, oxygen level (spo2 level) drops below 95, this is one of the major alarming signs.


There are five types of hypoxia they are,

Hypoxic hypoxia:

It occurs due to a decrease in arterial PO2 and a decrease in oxygen delivery to the tissues. To clarify, the arterial PO2 level means the amount of oxygen present in the blood arteries. Hence, this type of hypoxia often seen in fibrosis, pulmonary oedema, etc.,

Anaemic hypoxia:

The arterial PO2 level is normal, the amount of haemoglobin to carry oxygen is reduced. This type of hypoxia is more common in anemia.

Stagnant hypoxia:

The arterial PO2 level is normal the amount of hemoglobin is also normal. But the rate of blood flow to the tissues is reduced. Therefore, this type mainly occurs in shock, heart failure cases.

Histotoxic hypoxia:

The arterial PO2 is normal, the amount of Hb level is normal, the rate of blood flow to the tissues is also normal. But the tissue is not able to utilize the oxygen delivered to the tissues. This occurs due to toxic agents. This type of hypoxia seen in cyanide, sulfide poisoning, etc.

High altitude type of hypoxia:

This type of hypoxia usually seen in people who lived at sea level, sudden place of change to high altitudes, leads to this type of hypoxia. This is due to the difference in partial pressure of oxygen that varies from sea level to mountain level. Hence, with an increase in altitude, the partial pressure of oxygen usually falls down.


One of the alarming conditions observed in recent times is happy hypoxia. This develops in the younger population, mainly the age group of 20-30 years. It defined as the silent drop in oxygen level in the body. When the oxygen level drops below 94% in covid patients, they have breathlessness. Moreover, in this condition, there is no symptom when the oxygen level drops below 94%. There are no symptoms of covid 19 such as cough, fever, etc. When the oxygen level drops below 80 % patient has breathlessness, which turns into a fatal condition. Therefore, this affects the lungs severely. This needs immediate hospitalization.


The proper medical term for this condition is ‘silent hypoxia’. This is a warning sign for those who don’t check up on their oxygen levels regularly. Moreover, it is a warning sign for intermittent failure of vital body organs like the kidney, brain, heart, and its usually accompanied by breathlessness. Hence if not noticed properly, it will eventually lead to cardiac arrest, brain stroke finally may result in death.


This phenomenon is particularly high in young people, because they have high immunity, they can withstand the amount of hypoxia to some extent. That’s why these silent hypoxia cases have been reported late.


The symptoms of silent hypoxia vary from person to person they are:

  • Cough
  • Confusion
  • Sweating (without doing any physical works)
  • Wheezing
  • Shortness of breath( that is dyspnea)
  • Rapid breathing
  • Change of the colour of lips from natural tone to blue
  • Change of colour of the skin from red to purple.
  • Diarrhoea
  • Skin rashes.


Recently they have found that nearly 40% of young people affected with covid have more chances to develop this happy hypoxia. The symptoms are:

  • Shortness of breath or choking
  • Change of lip colour (turns blue)
  • The drop of oxygen level below 94%.


The pathogenesis of silent hypoxia is a shift in the oxygen – haemoglobin curve. This curve is responsible for maintaining oxygen and haemoglobin levels in our bodies.

The main reason for hypoxia in covid patients is V/Q mismatch to put in simple terms when one part of the lungs receive oxygen without blood flow. The loss of pulmonary vasoregulation in covid patients, which occurs in the early stages. Hence this leads to a low perfusion rate ( V/ Q mismatch). Therefore, this causes ground glass opacities seen in CT scans of covid patients. The main cause of hypoxia is intrapulmonary shunting and mismatched ventilation-perfusion ratio. To clarify, intrapulmonary shunting is the passage of deoxygenated blood (that is unpure blood) from the left side of the heart to the right side without precipitation of gases like oxygen, carbon dioxide, nitrogen, etc. This ultimately leads to reduced oxygen supply to the organs.


Pulse oximeter a compact, portable device used to assess the oxygen level in the blood. It is a non-invasive technique that measures the oxygen level, as well as the pulse rate in our body. A pulse oximeter works on the combined principle of spectrophotometry and plethysmography to non-invasively measures oxygen saturation in our body. Moreover, it works on oxygen saturation by passing the light through the body part. Hence, the sensors detect oxygen in your blood by comparing red and infrared light absorbed by the blood.

The normal level of oxygen is above 95%. If below, immediately consult your doctor. Hence its our duty to check up on the oxygen level, not only elders youngers, teenagers should check up their oxygen level.



Consume more amount of oxygen packed food such as nuts (cashews, Badams, walnuts, and accrues), fruits like apple, berries, oranges, kiwi, lemon, avocado. Coconut pieces increase our oxygen level, either in raw form or in the form of milk. This is proven to increase our blood oxygen levels.

Add more antioxidant-rich foods to your dietTurmeric is a very good antioxidant. Itboosts up our immune levels. They have found in recent times that reducing the number of carbohydrates in our diet is one of the best ways to boost up our immunity. Add up more greens, protein-rich foods.


If the oxygen level drops below 95, it’s very important to try proning position. It is a medically approved position to improve oxygen levels in our body. Therefore, post covid patients can do this daily to boost up their oxygen levels.


First, place three pillows on a flat surface. The first pillow placed below the neck. The second pillow should be placed below your pelvic area (belly should be free enough to let one hand pass below). The third pillow placed below the foot. The duration of this technique is 30 minutes.

There are three different positions to practice proning. They are, laying in a slanting position, holding in right side posture, completely rest on a flat surface by laying on your belly. You can practice any one of these positions daily. And also, can practice your convenient position daily for a duration of 30 minutes. All three are simple positions, can be done by all age groups of people. Hence, this is indicated for post covid patients, patients whose oxygen level drops below 95%.


To get a good amount of air, rooms should be well ventilated. It’s very important to open up your windows in the early morning time and get enough amount of sunlight. Hence, sunlight is the best remedy to get rid of all sorts of infections. A small walk in the garden areas is also good.


Growing plants in our household areas, gardens, purify the air, produce oxygen. They replenish the carbon dioxide. helps us to absorb more amount of oxygen. According to our Indian tradition,  known to emit a large amount of oxygen. Planting these trees in our surroundings, or the presence of these trees in our surroundings is very beneficial. According to our ayurvedic tradition, the banyan tree believed to cure many diseases. Hence, standing under a banyan tree for some time is the best remedy to increase our oxygen levels. And also neem tree also purifies more amount of oxygen.


To improve pulmonary rehabilitation, practice simple breathing exercises such as deep belly breathing, pursed lip breathing . This improves our oxygen levels in our body , opens up our breathing. Simple breath in and out itself is very beneficial.


Exercise is one of the best ways to lead a healthy life. Practicing aerobics, small home workouts, going for a small walk improves our lymphatic system. According to the American heart association, 30 minutes of walk every day improves our circulation and best way to get rid of any sort of disease.


Hyderabad reported many cases of happy hypoxia. This phenomenon still remains a mystery among doctors.

One case was reported in Indonesia when post covid patient came for a check-up. The patient was able to walk with no breathing difficulty or symptoms of covid. While examining pulse rate was normal. The oxygen saturation was 77%.

Similarly, cases was reported in India in July 2020. This condition is often associated with Covid-19.


To conclude, daily check your oxygen levels using pulse oximeters. Everyone should be aware of this condition, which is affecting this second wave of covid. Hence, it’s our duty to take necessary precautions to prevent this kind of deadly condition. Self-care is more important nowadays, implementing regular habits in our day-to-day life makes to lead a healthy life.

Like it? Share with your friends!

Dr Shalini S.G
I am a dental surgeon. I love travelling and listening to music and a passionate person in research and doing lots of presentation. My area of interest is pathology, diagnosis and forensics.