Blood oxygen saturation indicates the percentage of oxygen carried by red blood cells throughout the body. This measure, SpO2, provides insight into how efficiently the lungs deliver oxygen to the bloodstream. Maintaining healthy oxygen levels is important for organ function and well-being. A low oxygen level, such as 85%, signals a serious medical condition requiring immediate attention.
Understanding Oxygen Saturation
Oxygen saturation (SpO2) is the amount of oxygen in a person’s blood. For most healthy adults, normal oxygen saturation ranges between 95% and 100% when measured with a pulse oximeter. Levels below this range indicate a problem, with lower percentages signaling more severe conditions.
An oxygen saturation level of 85% indicates severe hypoxemia, meaning there isn’t enough oxygen in the blood. Such a low level can impact the brain and other vital organs, leading to serious complications. Symptoms of dangerously low oxygen levels include severe shortness of breath, confusion, dizziness, and a bluish tint to the lips or face.
Monitoring Oxygen Levels at Home
A pulse oximeter is a small device that measures blood oxygen saturation. It clips onto a body part, usually a fingertip, emitting light that passes through the tissue. A sensor detects the light absorbed by the blood, calculating the SpO2 percentage.
For accurate readings, ensure your hand is warm and still, and remove nail polish or artificial nails from the tested finger. Several factors can affect the accuracy of a pulse oximeter, including poor circulation, skin temperature, excessive movement, and ambient light. Additionally, pulse oximeters may be less accurate for individuals with darker skin tones due to melanin interfering with light absorption.
How COVID-19 Affects Oxygen
COVID-19 primarily leads to low oxygen levels by affecting the lungs. The virus can cause inflammation, pneumonia, and Acute Respiratory Distress Syndrome (ARDS), impairing the lungs’ ability to transfer oxygen to the blood. This damage to the air sacs can disrupt oxygen diffusion through their membranes.
A notable phenomenon in some COVID-19 patients is “silent hypoxia” or “happy hypoxia,” where individuals have dangerously low oxygen levels without significant shortness of breath. This can occur because the lungs may initially remain compliant and able to expel carbon dioxide, delaying the sensation of breathlessness despite low oxygen. This condition highlights why monitoring oxygen levels is important, even if symptoms feel mild.
Responding to Low Oxygen Levels
If your oxygen saturation consistently drops below 90%, it is a medical emergency. Call 911 or go to the nearest emergency room for immediate medical attention. This is important if you experience symptoms such as severe shortness of breath, confusion, chest pain, or a bluish discoloration of your lips, face, or fingernails.
For oxygen levels between 91% and 94%, it is advisable to contact your healthcare provider immediately for guidance. While awaiting medical help for critically low levels, sitting upright or trying prone positioning (lying on your stomach) if comfortable may help improve breathing and oxygen saturation. Do not attempt to self-treat severe drops in oxygen levels; professional medical evaluation is required to determine the underlying cause and appropriate interventions.