What percentage is the oxygen saturation measured during the medical treatment of the new colona?

What is oxygen saturation?

The oxygen saturation of the blood of the body can be measured by using a machine that is on the finger called "pulse oximeter".You see whether oxygen is imported into your body from the air.

血液の中には、酸素を運搬してくれる「赤血球」という運び屋がいるのですが、赤血球の中にある「ヘモグロビン」というタンパクが酸素と結合することが重要です（図1）。ヘモグロビンの何％が酸素とくっついているかを見るのが「酸素飽和度」です。指に挟む機械でなぜ簡単にこれが分かるのかというと、爪という窓を通して毛細血管の色の変化などをみているのです。すごい技術ですね。

By the way, what is the normal value of oxygen saturation?

日本呼吸器学会(1)によれば、96～99％が正常値とされています。100％になることはあまりなくて、過呼吸になって呼吸数がはやい人くらいにしか起こりません。

Just as the reference value of the hypertension of the consultation room is 140 mmHg or more, it is not an abnormality immediately if the reference value is removed even if the reference value is removed.If you measure your blood pressure immediately after exercising, you will get high, and just because it is 141mmHg, you don't have to worry about "I'm high blood pressure."

Similarly, if you measure a short walk, the oxygen saturation may be about 93 to 95 %, and just because it is instantaneously lower than 96 %, it will not be immediately abnormal.If I wear a mask during the outpatient and talk to the patient, it may decrease to about 93 %.

The standard for the new colona Ichi is "less than 96 % of oxygen saturation", but for the above reasons, I feel that it is somewhat conservative.It is more important to have pneumonia and whether or not breathing is strong.

ただ、いかなる場合でも医師が容認できないラインが90％です。このラインを切ってくると「呼吸不全」と呼びます。これは間違いなく異常です。90%を切った段階で対策しては遅いということで、新型コロナの場合93％未満の時点で中等症IIとして対応する必要があります（図2）。

Until the fifth wave surface, the Tokyo Metropolitan Government was hospitalized for less than 96 % oxygen saturation.Certainly, the normal value of oxygen saturation is 96 % or more, so it is not a mistake, but as I wrote earlier, it is often about 93 to 95 % for healthy people.For this reason, it is a realistic drop that is hospitalized in a case where dyspnea or less than 90-93 % of cases are more difficult to breathe or less than 90 to 93 %, rather than excessively picking up a slight decrease in a slight decline.I think it is.

If the bed is still tight, you need to inhale oxygen at home.

■ Reference article: New Corona If oxygen is needed during medical treatment (url: https://news.yahoo.co.jp/byline/kuraharayu/20210808-00252121)

Why isn't it good if oxygen saturation decreases?

This is because it affects organs such as the heart and brain.Just because the oxygen saturation drops below 90-93 % does not mean that the heart or brain is done at that moment.If you sprint 100 meters, the oxygen saturation will decrease, but the athletic player does not fall as soon as you go.Leaving the condition is a problem, and if the oxygen saturation is low, there is a risk that health will have a negative effect.

It is more likely to cause shortness of breath, tachycardia, and arrhythmia, and may fall into a coma.

Beware of early dust

パルスオキシメーターは、脈拍と酸素飽和度（SpO2）の2つの数字が表示されます。これらの数字、非常に似通っており、見分けにくい機種が存在します（図3）。

In some cases, it was interpreted as "80 times/min, oxygen saturation 95 %", but "oxygen saturation 80 %, pulse 95 times/min".

In addition, if you put it on your finger, the number of oxygen saturation will appear in a few seconds, but since the average value of the last few seconds is updated every second, the number is low at the moment of measuring.It might be.Even in my outpatient clinic, the moment I put on the pulse oximeter, the patient may be surprised, "Eh! Is it so low!?"As you rest, the numbers will rise more and more.Therefore, look at the oxygen saturation numbers after 20 to 30 seconds when the pulse stabilizes.

And if you have a high fever due to the new colona, the oxygen saturation may be lower than that.If you know the heat of the new Corona, I personally think that you should actively take antipyretic analgesics.

また、下記の記事でも書きましたが、①手が冷たい、②爪の病気、③ネイル・マニキュア、④パルスオキシメーターが粗悪品、などの条件では酸素飽和度の数字に信頼がおけないこともありますので注意してください。

■ Reference article: Large-selling with Corona (URL: https://news.yahoo.co.jp/byline/kuraaharayu/20210524-00236880)

(reference)

(1) Japanese Respiratory Society. Pulse oximeter that is well understood