The ongoing Covid-19 pandemic has introduced medical practitioners to a new condition called ‘silent’ or ‘happy hypoxia’. In this situation, patients exhibit extremely low blood oxygen levels without showing signs of breathlessness. This has caused confusion among healthcare providers and contributed to urgent calls for early detection to prevent a lethal sickness known as Covid pneumonia.
Understanding Hypoxia
Hypoxia is a health condition in which not enough oxygen is accessible to the blood and body tissues. It can be generalized, affecting the entire body, or local, affecting a specific area of the body.
Under normal circumstances, arterial oxygen is approximately 75 to 100 millimetres of mercury (mm Hg), and typical pulse oximeter readings range from 95 to 100%. Values under 90% are considered low. If these levels drop below 90%, patients might start to experience lethargy, confusion, or mental disruptions due to an inadequate supply of oxygen to the brain. Further, if the levels slide below 80%, it could result in damage to vital organs.
The Phenomenon of Silent Hypoxia
Silent hypoxia is a type of oxygen deprivation that is harder to identify than regular hypoxia. This is because patients seem less distressed despite their low oxygen levels. Silent hypoxia often precedes Covid pneumonia, a serious medical condition found in severe Covid-19 patients.
Oddly, various Covid-19 patients whose oxygen levels were below 80% seemed relaxed and alert. There have even been a few instances of oxygen levels dropping below 50%. Generally, individuals with such low oxygen levels appear gravely sick, but this is not the case with silent hypoxia.
In many instances, Covid-19 patients with silent hypoxia did not exhibit symptoms such as shortness of breath or coughing until their oxygen levels dropped to dangerously low levels. This precipitated risks of acute respiratory distress (ARDS) and organ failure.
Reasons Behind Silent Hypoxia
People usually feel breathless not because of the fall in oxygen levels itself but due to simultaneous increases in carbon dioxide levels. This happens when the lungs are unable to expel this gas efficiently. In several Covid-19 cases, this was not the response observed, and patients did not report feeling breathless.
In patients suffering from Covid pneumonia, the virus causes air sacs to collapse, thereby decreasing levels of oxygen. However, the lungs initially do not stiffen or fill with fluid while remaining compliant, meaning they can still expel carbon dioxide and prevent its buildup. As a result, patients do not feel short of breath.
The Role of Pulse Oximeter in Early Detection
A medical device called a pulse oximeter can potentially detect silent hypoxia early. This is particularly useful for active Covid-19 sufferers or those suspected to have the disease. They can check their oxygen levels early on using the device. If these levels fall, it could serve as a signal to seek additional treatment immediately. Though some concerns have been raised about the frequent use of this device leading to increased anxiety.
The pulse oximeter measures the saturation of oxygen in red blood cells (RBCs). It can be attached to a person’s fingers, toes, nose, feet, ears, or forehead. Its use is simple and painless, and the device can be reused or discarded after use.
Covid Pneumonia: A Lethal Condition
Covid pneumonia is a potentially fatal condition in Covid-19 patients that hampers the lungs’ ability to transfer oxygen and causes breathing difficulties. When a person cannot inhale enough oxygen or exhale enough carbon dioxide, this pneumonia can turn deadly.
Covid pneumonia is particularly severe because it impacts the entire lungs rather than small parts, unlike other types of pneumonia typically caused by bacteria and treatable with antibiotics. In severe cases requiring ventilator support, the focus is on facilitating adequate oxygen circulation in the body.
Last Modified: February 7, 2024