Oxygen Please

When I visit my Doctor for a regular visit the first thing done by a Nurse is to record my ‘vitals’. I cannot remember when it started but a regular reading is my saturated oxygen level, pulse rate and blood pressure. My general doctor is a cardio-pulmonary specialist which probably caused saturated oxygen level to be added quickly to the vitals group. I had occasional breathing congestion for so many years I cannot remember and at one point they, medical profession, gave it the name of COPD. Unfortunately there are many of us with widely varying problems grouped in this category because the first letter stands for Chronic. Whatever the history, oxygen is important and the standard it 95%-100%. For us with ‘conditions’, 90%-100% is good. This value has never indicated a problem for me.

Now I read that Covid-19 can cause a lower value, even to 50%, without showing respiratory distress. What this means for us is that Covid-19 will start by lowering the value before it goes real low and you feel it. I actually did not find any indication that the value drops as the disease worsen only that doctors find the value low!

In an article ‘Can a Pulse Oximeter Save Your Life if You Have COVID-19?’ Dr. Richard Levitan, who’s been an emergency room physician for some 30 years reports his experience with Covid-19 patients durning a stay in an ER of a large NYC hospital. excerpts follow.

A pulse oximeter works by passing beams of light through your finger and calculating blood-oxygen levels based on light absorption.

Dr. Levitan refers to this hard-to-detect type of oxygen deprivation (or hypoxia) as a silent killer. After observing patients during a 10-day volunteering stint in the ER at Bellevue Hospital in Manhattan, he wrote about this aspect of the virus in an opinion piece in The New York Times. I reviewed this article in my post in April. The question is the ‘hard-to-detect’seems to be done regularly by my general doctor every visit. The oxygen depletion may not be apparent immediately because the virus attacks the lungs in such a way that the patient gradually gets less and less oxygen over time, according Levitan. “These patients do not feel like they have breathing difficulty because they slowly adjust to the lower oxygen,” he says. The oximeter may provide a simple way to spot potential health trouble, but it’s not a substitute for a doctor’s consultation. “Why not have one?” he says. “A pulse oximeter is a very easy gadget to use. It’s not costly and it’s not invasive. Within 10 to 15 seconds, you’ll get an oxygen saturation reading. If it plummets below 90, you may need supplemental oxygen.”

Some people with the novel coronavirus have alarmingly low levels of blood oxygen, and they don’t even have a clue that their lives are in danger. They don’t appear to have any major trouble breathing, so they don’t realize how dire their situation may be. The phenomenon has been raising concern among doctors, because these individuals typically need emergency medical attention to survive. “The level of oxygen that these people are reaching can be so low that it’s amazing to me not only that they’re alive, but that they’re often not in distress,” says Richard Levitan, MD, an emergency physician in Littleton, New Hampshire, and the president of Airway Cam Technologies, a company that teaches courses in intubation and airway management. “They may be awake, alert, and even on their cell phones.” According to Levitan, he and other doctors are seeing many coronavirus patients who are breathing fairly well when they check in to the hospital, but upon examination it’s clear they have pneumonia and their lungs are failing to sufficiently oxygenate their blood. A normal blood oxygen reading would be between 95 and 100 percent, according to the Mayo Clinic. Anything under 90 is considered unhealthy. While at Bellevue in March, Levitan saw coronavirus patients with measurements as low as 50 percent. When oxygen levels sink this far, Levitan expects patients to have much more apparent trouble breathing. Instead, these patients were often coming into the ER only after recently noticing a shortness of breath and having been sick with symptoms like fever, cough, upset stomach, and fatigue for a week.

He was perplexed. “If you get this low with your oxygen, your brain doesn’t like it,” he says. “You have respiratory failure, you pass out, or you have a seizure.” But that wasn’t happening with the patients he was seeing. He explains that with COVID-19, the lungs initially remain “compliant,” meaning not yet stiff or heavy with fluid, so they’re able to get rid of carbon dioxide even as their ability to provide oxygen to the body becomes impaired. A buildup of carbon dioxide would cause patients to become lethargic or unconscious. To compensate, individuals breathe faster and deeper, and this change in respiration, Levitan says, increases inflammation in the lungs while also, for a while, masking some symptoms of pneumonia.

Identifying pneumonia early on before it advances can help a patient beat the disease and perhaps avoid more extreme measures like being put on a ventilator. “Through all of medicine, we know that earlier diagnosis and earlier treatment make a difference,” says Levitan. He adds that some of the most effective interventions can also be the least complicated. “For example, giving people oxygen and turning people onto their stomach — what we call proning — can reduce ventilator necessity,” he says. “People come in with oxygen levels in the 50s, and after we’ve turned them on their stomachs and given them oxygen their oxygen levels are in the 90s.” “Fixating on pulse oximeter readings may provide a false sense of security,” warns Albert Rizzo, MD, the chief medical officer for the American Lung Association. “In some cases, they do catch lung problems before you struggle with shortness of breath. However, it is also possible for the device to show healthy oxygen saturation levels even when experiencing trouble breathing, which may lead some individuals to delay seeking urgently needed care.” “Everybody I know has anxiety about this disease,” he says. “One way to give patients assurance that they’re okay is to empower them to self-monitor, and adding pulse oximetry does that.