How Wearable Pulse Oximeters Help Long COVID? Real-world Hypoxemia Cases
- viatomtechnology
- Mar 24, 2021
- 6 min read
Updated: Feb 11
Since the COVID-19 pandemic began, millions have experienced long COVID symptoms. How does hypoxemia contribute to these COVID long-term effects? Why are wearable pulse oximeters recommended to improve patient management? How can clinics choose the right oximeter? Let’s explore these questions and examine the vital role of oxygen monitoring in post-COVID care.
Long COVID Symptoms Due to Silent Hypoxemia
Emerging evidence highlights that hypoxemia—particularly when it is unnoticed, known as “silent hypoxemia” or “happy hypoxemia”—plays a key role in both the immediate severity and long-term COVID symptoms.
A 2022 study pointed out that many COVID-19 patients with severe hypoxemia experienced prolonged disorders of consciousness and cognitive impairments. These neurocognitive issues continued to last for weeks after stopping ventilator support. Importantly, the severity of these sequela was closely related to patients’ hypoxemia levels, independent of brain injury or sedation effects[1]. The study suggested that hypoxemia itself may underlie these after-effect COVID-19 neurological problems.
Additionally, a study from Rwanda found that low oxygen saturation at admission—often without any overt symptoms—was the strongest predictor of critical deterioration[2]. This highlights that if hypoxemia is not detected and managed, it can result in worse COVID long-term effects.
Together, these findings underscore the critical importance of detection and management of hypoxemia are essential for reducing post-COVID symptoms and improving patient outcomes. The main method includes routine, objective monitoring of oxygen levels.
What is hypoxemia? Types, symptoms, causes, and risks
Hypoxemia means a below-normal saturation of oxygen in the blood, especially in the arteries. This reduced oxygen level can cause many medical problems, such as shortness of breath, headache, coughing, problems with breathing, and circulation. So Hypoxemia is a severe medical condition, and it requires prompt medical attention.
Hypoxia vs Hypoxemia
Hypoxemia refers specifically to low oxygen levels in the blood. If severe or prolonged, hypoxemia will lead to hypoxia, a broader condition of insufficient oxygen supply to the body's tissues and organs.[3]
Hypoxemia Types
There are different types of Hypoxemia, and the following list contains the most common types:
a. Ventilation/perfusion (V/Q) mismatch
b. Shunt
c. Diffusion impairment
d. Hypoventilation
e. Low environmental oxygen
Hypoxemia Symptoms
Some of the significant symptoms of Hypoxemia include: headache, shortness of breath, fast heartbeat, coughing, wheezing, confusion, bluish color in fingernails, lips, and skin.
The term “silent hypoxemia” or “happy hypoxemia” was introduced early in the COVID-19 pandemic to describe patients who presented with severe hypoxemia and absence of dyspnea[4].
Hypoxemia Causes
Different factors cause hypoxemia in your body. Some of them are given in the list below;
a. Heart defects
b. Lung conditions, i.e., asthma, bronchitis, and emphysema
c. High altitude
d. COPD
e. A collapsed lung
f. Acute respiratory distress syndrome (ARDS)
g. Sleep apnea (a disturbed breathing condition during sleep)
h. Inflammation of lung tissues
Hypoxemia Hazards
Hypoxemia is a severe medical condition that, if not cured at the right time, can cause some dangerous complications. In the long term, it can also affect the functioning of your heart or brain. So, diagnosing and treating hypoxemia at the right time is very important.
How to monitor and manage hypoxemia? Role of wearable pulse oximeters
The early detection and continuous monitoring of hypoxemia, especially silent hypoxemia, are the best ways to reduce the harm of hypoxemia. Lack of dyspnea is common in patients suffering from severe COVID-19 pneumonia, leading to respiratory failure, since up to a third of them could be asymptomatic on admission[5].
Almost all countries are calling for people to use a wearable pulse oximeter to monitor hypoxemia during COVID-19. Physicians are finding that many patients have very low oxygen readings, but remain in no apparent discomfort. By the time symptoms appeared, the condition had evolved into a serious illness.
Once the blood oxygen level drops to an acutely low level, it can even cause death. There are some ways of curing hypoxemia, such as oxygen masks and a small tube clipped to your nose to provide supplemental oxygen. The first line of defense is to have a record of your blood oxygen level. You can record your blood oxygen level with a wearable pulse oximeter or a fingertip pulse oximeter.
How to choose wearable pulse oximeters for continuous SpO2 monitoring?
A wearable pulse oximeter is a convenient and non-invasive device that continuously monitors blood oxygen levels, providing valuable insights for health-conscious individuals and those at risk of hypoxemia, such as COVID-19 patients. Wearable pulse oximeters offer other benefits as well, such as remote monitoring, sleep monitoring, etc.
Below, we explore three common types of wearable pulse oximeters and highlight their unique features and advantages.
1. Ring pulse oximeter
A ring oximeter is attached to your thumb or other fingers, depending on the ring size, typically during sleep or daily activity. It enables continuous monitoring of blood oxygen levels, pulse rate, and body movement, enabled by a secure, ergonomic design that prevents slippage.
Viatom ring pulse oximeter features:
A soft, flexible design for unmatched comfort
A touchable screen with real-time SpO2 reading
A built-in rechargeable battery for 12h+ use
Instant vibration for abnormal heart rate/oxygen level
Advanced sensors for darker skin tone accuracy
Seamless data synchronization to the mobile App
Suitable for:
Overnight use
24/7 personal wellness tracking
At-home respiratory condition management
2. Fingertip pulse oximeter
A fingertip pulse oximeter is a small clip-like device that helps detect your blood oxygen level and heartbeat. Simply stay still, hold the hand at your heart level, and read immediate readings. For fingertip oximeters, factors such as nail polish may impact accuracy.
Viatom fingertip pulse oximeter features:
Larger OLED screen showing battery status and PR reading
Higher-resolution display with multiple colors
Competitive price for clinic stock
Advanced sensors for darker skin tone accuracy
Seamless data synchronization to the mobile App
Suitable for:
Quick health checks at home
Instant spot-checks in hospitals and clinics.
3. Wrist pulse oximeter
A wrist pulse oximeter usually features a comfortable wrist strap, and some models include a separate finger sensor, enabling hands-free, continuous monitoring. Its key advantage is patient comfort and stability during extended use, particularly overnight.
Viatom wrist pulse oximeter features:
Larger OLED screen showing PR reading
A higher sampling rate of 1 second
Separate, flexible sensor choices (ring/duckbill)
Extended 16- to 100-hour battery life
Reliable, stable wearing experience
Advanced sensors for darker skin tone accuracy
Seamless data synchronization to the mobile App
Suitable for:
Continuous overnight monitoring (including sleep studies)
Remote patient monitoring
Chronic respiratory condition management
Frequently Asked Questions
What oxygen level is hypoxemia?
Hypoxemia is classified by the level of oxygen in your arterial blood, typically measured via an arterial blood gas (ABG) test for PaO2 readings or a pulse oximeter for SpO2 readings.
Arterial Blood Gas (PaO2) level:
Normal: 75-100 mmHg
Hypoxemia: Below 60 mmHg
Blood Oxygen Saturation (SpO2) level:
Normal: 95-100%
Hypoxemia: Below 90%
What are the dangers of hypoxemia?
Mild/Light Hypoxemia:
Level: PaO2 60-79 mmHg | SpO2 90-94%
Key danger: Body strain & reduced function
Common symptoms: Shortness of breath with activity, fatigue, headache
Moderate Hypoxemia:
Level: PaO2 40-59 mmHg | SpO2 75-89%
Key danger: Onset of organ stress, especially to the heart & brain
Common symptoms: Confusion, fast heart rate, shortness of breath at rest, bluish lips/fingers
Severe Hypoxemia:
Level: PaO2 <40 mmHg | SpO2 <75%
Key danger: Organ failure & death
Common symptoms: Medical emergency, such as extreme confusion, loss of consciousness, severe breathing difficulty
What are the first signs of hypoxemia?
Your body’s immediate response to hypoxemia includes:
Headache
Increased heart rate (>100bpm) and breathing to get more oxygen
Bluish skin
How do you treat hypoxemia?
Hypoxemia treatment generally involves receiving extra oxygen. This treatment is called supplemental oxygen or oxygen therapy. Specific equipment is chosen based on severity:
Supplemental Oxygen (mild to moderate):
Nasal Cannula: A lightweight tube for the nostrils.
Face Mask: Covers nose and mouth for higher oxygen flow.
Oxygen Concentrator/Tank: Provides long-term or portable oxygen.
Breathing Support (moderate to severe):
CPAP/BiPAP machine: Uses air pressure to keep airways open and assist breathing.
Advanced Support (severe):
Mechanical Ventilator: Breaths for you in life-threatening respiratory failure.
Hyperbaric Chamber: Delivers pure, pressurized oxygen for specific emergencies.
Other therapies target the underlying cause of hypoxemia, including bronchodilators for lung disease, diuretics for heart failure, antibiotics for infections, and blood transfusions for anemia.
About Us
Viatom's wearable pulse oximeter uses a high-quality chip with more accurate blood oxygen pulse signal capture and more computational power. Our products have provided medical assistance in more than 60 countries during Covid-19. Viatom has always been involved in the life and health business and has been a pioneer in the field of home medical care by building a healthy ecosystem from prevention to rehabilitation, by bringing the medical market and the home market together.
Reference:
[1] Prolonged Unconsciousness is Common in COVID-19 and Associated with Hypoxemia (2022)
[2] Prevalence and predictors of critical COVID-19 pneumonia among patients with COVID-19 admitted at Nyarugenge major COVID-19 Referral Center in Rwanda (2025)
[3] What is Hypoxemia: Causes, Symptoms, Treatment and Prevention (2025)
[4] Happy or Silent Hypoxia in COVID-19–A Misnomer Born in the Pandemic Era (2021)
[5] Frequency, characteristics, and outcome of patients with COVID-19 pneumonia and “silent hypoxemia” at admission: a severity-matched analysis (2022)
