The Effects Of Silent Hypoxia

Hypoxia is a situation in which the blood and bodily tissues do not receive adequate oxygen. Hypoxia can be generalised, affecting the entire body, or localised, affecting a specific bodily part.

The normal arterial oxygen level of 80 is 75 to 100 millimetres of mercury (mm Hg), and normal pulse oximeter values are 95 to 100 percent, according to the Mayo Clinic, an American non-profit organisation. Low values are defined as those that fall below 90%. When fatal oxygen level 80 falls below 90%, patients may experience lethargy, confusion, or mental disturbances as a result of insufficient oxygen reaching the brain. Vital organs may be harmed if the concentration falls below 80%.

Why is it in the news?

During the ongoing Covid-19 pandemic, doctors have discovered a phenomenon known as silent or joyful hypoxia, in which patients have dangerously low blood oxygen levels of 80 yet show no signs of breathlessness.

It has perplexed doctors, and many are now calling for early discovery as a means of avoiding a lethal condition known as Covid pneumonia.

Key Points:

Hypoxia

• It is a condition wherein there is not enough oxygen available to the blood and body tissues.
• Hypoxia can either be generalised, affecting the whole body, or local, affecting a region of the body.Normal arterial oxygen is approximately 75 to 100 millimetres of mercury (mm Hg) and normal pulse oximeter readings usually range from 95 to 100%.
  • Values under 90% are considered low.
• When levels fall below 90%, patients could begin experiencing lethargy, confusion or mental disruptions because of insufficient quantities of oxygen reaching the brain.
  • Levels below 80% can result in damage to vital organs.

Silent Hypoxia

• It is a form of oxygen deprivation that is harder to detect than regular Hypoxis because patients appear to be less in distress.
• Covid pneumonia, a serious medical condition found in severe Covid-19 patients, is preceded by silent hypoxia.
• Many Covid-19 patients with oxygen levels of 80 look at ease and alert. There have been a few cases of Fatal oxygen levels below 50% as well.
  • Those with such low levels of oxygen would normally appear extremely ill but not in silent hypoxia cases.
• In many cases, Covid-19 patients with silent hypoxia did not exhibit symptoms such as shortness of breath or coughing until their oxygen fell to acutely low levels, at which point there was a risk of acute respiratory distress (ARDS) and organ failure.

Reasons:

• The reason why people are left feeling breathless is not because of the fall in oxygen levels itself but due to the rise in carbon dioxide levels that occur at the same time when the lungs are not able to expel this gas efficiently.

• In some Covid-19 cases, this was not the response and patients did not feel breathless.
• It happened because, in patients with Covid pneumonia, the virus causes air sacs to fall, leading to a reduction in levels of oxygen. However, the lungs initially do not become stiff or heavy with fluid and remain compliant meaning they are able to expel carbon dioxide and avoid its buildup. Thus, patients do not feel short of breath.

A medical device called a pulse oximeter can be used in the early detection of silent hypoxia.

• Active Covid-19 or suspected cases can check their oxygen levels early on by using the device.
• A fall in oxygen levels can serve as a signal for seeking additional treatment immediately.
• Concerns have been raised against it arguing that the frequent use of the device would lead to increased anxiety.

Pneumonia in Covids

It is a potentially fatal disease that inhibits the lungs’ ability to transport oxygen and creates breathing difficulties in Covid-19 patients.

Pneumonia can be fatal if a person is unable to breathe enough oxygen or exhale enough carbon dioxide. Covid pneumonia is particularly dangerous because it is viral and attacks the entire lungs rather than just a few tiny areas.

Other types of pneumonia, such as those caused mostly by bacteria and treatable with antibiotics, are less severe than Covid pneumonia.

In such extreme cases, patients must be placed on ventilator support to guarantee enough oxygen circulation throughout the body.

Conclusion:

Covid pneumonia, a deadly medical illness reported in severe Covid-19 sufferers, is preceded by ‘silent hypoxia,’ a type of oxygen deprivation that is harder to detect than typical hypoxia, according to a New York Times opinion post by physician and inventor Dr Richard Levitan. Patients with ‘silent’ or ‘happy’ hypoxia appear to be less distressed. 

People experience shortness of breath not because of a decline in oxygen levels, but because of a spike in carbon dioxide levels, which occurs when the lungs are unable to efficiently remove this gas. This response does not appear to be kicking in in other Covid-19 patients.