Mysterious ‘happy hypoxics’: What doctors know about the latest coronavirus condition
Doctors are learning that what’s happening outside a coronavirus patient is not a true reflection of what’s happening on the inside.
Patients with COVID-19 — the disease the virus causes — with dangerously low blood-oxygen levels appear to have normal breathing, yet such levels usually amount to unconsciousness or even death, according to U.S. doctors.
The phenomenon is called hypoxia, and medical professionals are trying to figure out if early detection along with home monitoring can make the difference between life or death, especially now that most people are afraid to step foot in a hospital.
“It’s intriguing to see so many people coming in, quite how hypoxic they are,” Dr. Jonathan Bannard-Smith, a consultant in critical care and anesthesia at Manchester Royal Infirmary in England, told The Guardian. “We’re seeing oxygen saturations that are very low and they’re unaware of that. … It’s very much more profound and an example of very abnormal physiology going on before our eyes.”
Normal blood-oxygen levels tend to stand between 95% and 100%; anything below the minimum can lead to shortness of breath, rapid heartbeat and chest pain, according to Healthline.
But COVID-19 patients don’t seem to be showing these symptoms, despite having oxygen saturation levels in the 80s or 70s, with some pushing below 50%, The Guardian reported.
Clinicians are calling them “happy hypoxics.”
These levels are similar to those of people in high altitudes, such as mountain climbers.
Part of the reason is that the brain is not equipped to monitor drops in oxygen levels.
“The brain is tuned to monitoring the carbon dioxide with various sensors,” Paul Davenport, a respiratory physiologist at the University of Florida, told Science Magazine. “We don’t sense our oxygen levels.”
This means that people will be able to breathe comfortably, despite low blood-oxygen levels, until their lungs can no longer expel carbon dioxide, sending alarming signals to the brain.
Other possible explanations are simply unknown, scientists admit.
There’s growing evidence that SARS-CoV-2 — the virus driving the pandemic — can cause clots to form in the blood. The clots could then block oxygen flowing through tiny, already-inflamed vessels in the lungs from entering the bloodstream.
To combat this, some doctors are experimenting with blood thinners to prevent and treat severe COVID-19 complications, outlets report.
A pulmonologist from São Paulo, Brazil, gave heparin — a common blood thinner — to a patient who had breathing troubles and circulatory problems in her toes, and both issues recovered, according to Science Magazine.
Elnara Marcia Negri later conducted a small study of 26 COVID-19 patients and gave them the medication regardless of whether they were struggling to breathe, the magazine reported.
Of the sample, 24 patients started to recover while the last two remained critically ill, Negri said in her preprint published in April in medRxiv.
Other medical professionals, however, say “doctors should avoid aggressive treatment they’ve been trained to offer in other settings,” Science reported.
Throughout the pandemic, doctors have been putting patients experiencing hypoxia on a ventilator to inflate their lungs even when their breathing was normal. It’s what one German doctor calls the “Pavlovian response to COVID-19,” the outlet said.
However, the practice could be harming patients’ lungs that are working fine on their own, the doctor, Luciano Gattinoni, revealed in his study published in April in the journal JAMA.
Therefore, home monitoring using pulse oximeters — a device that measures oxygen levels through your finger — is on the list of potential ways to help these “happy hypoxics,” experts say. But there lacks evidence that early detection of hypoxia could help patients who might later need to go to the hospital.
“Transportation of the devices would put more people on the road,” Dr. Mike Charlesworth, an anesthetist at Wythenshawe hospital in Manchester, England, told The Guardian. “Then there are issues around people buying them on the internet and whether they (have proper safety certificates). … If you’re at the point of needing your oxygen levels monitored, that’s the time to go to hospital.”
This story was originally published May 4, 2020 at 12:07 PM with the headline "Mysterious ‘happy hypoxics’: What doctors know about the latest coronavirus condition."
