血氧(Blood)测量是新一代Apple Watch 机型(Apple Watch models)的旗舰健康相关功能。这是对您的红细胞从肺部输送到身体其他部位的氧气量的估计。
这篇博文将解释Apple Watch 血氧(Apple Watch Blood Oxygen)传感器如何测量您的血氧水平。此外，您将学习如何在您的新Apple Watch和 iPhone上设置血氧应用程序。(Blood Oxygen)
Apple Watch(Apple Watch Measures)如何测量您的血氧(Blood)
Apple Watch Series 4、Series 5、Series 6和Series 7具有测量心率的光学心脏传感器。然而，Apple Watch Series 6和Series 7 以及(Series 7—and)可能更新的型号上的心脏传感器可以测量心率和血氧水平（也称为氧饱和度水平）。
测量血氧时，Apple Watch会向您的手腕发出明亮的红色和绿色LED灯以及红外线。血液(Blood)反射红色，因此光电二极管(Photodiode)传感器测量皮肤中血液反射的红光量。
这就是Apple Watch Series 6和Series 7如何确定您的血液含氧量的方式。通常，您的血液反射的红光越多，您的血氧含量就越高。
如何设置 Apple Watch 的血氧功能(Blood Oxygen Feature)
(Blood)兼容的Apple Watch(Apple Watch)型号默认禁用血氧测量。要使用该功能，请在Apple Watch上启用(Apple Watch)血氧(Blood Oxygen)测量。然后，配置 iPhone Health应用程序以接收来自(Health)Apple Watch的血氧数据。
设置血氧应用程序(Set Up the Blood Oxygen App)
在Apple Watch(Apple Watch)设置中启用血氧测量会激活血氧(Blood Oxygen)应用程序。
打开Apple Watch 上的“设置”应用，轻点(Settings app)“血氧(Blood Oxygen)”，然后打开“血氧测量”(Blood Oxygen Measurements)。
或者，您可以通过 iPhone 上的Watch应用远程设置Apple Watch Blood Oxygen 。打开手表应用程序(Watch app)，转到我的手表(My Watch)>血氧(Blood Oxygen)，然后打开血氧测量(Blood Oxygen Measurements)。然后(Afterward)，选择您是否希望血氧(Blood Oxygen)应用程序在剧院和睡眠模式下进行背景测量。
【注】(Note:)如果您所在的国家或地区不提供血氧(Blood Oxygen)服务，您将不会在Apple Watch上找到该服务。(Apple Watch)如果您不能等到Apple将应用程序推广到您所在的国家/地区，请(Apple)更改您的 App Store 国家(Change your App Store country)/地区。访问此watchOS 功能可用性页面(watchOS feature availability page)以查看可以使用血氧(Blood Oxygen)应用程序的国家/地区。
在 Health App 中设置血氧测量(Set Up Blood Oxygen Measurement in the Health App)
(Blood)Apple Watch上的血氧测量值会记录在iPhone 上的“健康”应用中。(Health)在Apple Watch(Apple Watch)上启用血氧测量(Blood Oxygen Measurements)后，请按照以下步骤在“健康(Health)”应用中启用血氧：(Blood Oxygen)
- 在 iPhone 上打开“健康”应用，输入个人健康详情，然后轻点(Health)“完成”(Done)以设置您的健康档案。
- 如果您的Apple Watch和 iPhone 已连接，健康(Health)应用程序应显示启用血氧的提示。(Blood Oxygen)点击启用(Enable)以继续。
- 如果您没有收到此提示，请前往Browse选项卡，点击Respiratory，选择Blood Oxygen，然后点击Enable。然后，继续下一部分进行第一次血氧测量。
在“健康(Health)”应用中找不到血氧(Blood Oxygen)？将您的 Apple Watch(Update your Apple Watch)和 iPhone 分别更新到最新版本的 watchOS 和 iOS。
值得一提的是，血氧(Blood Oxygen)测量仅适用于 18 岁及以上的用户。如果您的健康档案(Health Profile)中的年龄低于 18 岁，您将不会在健康(Health)应用程序中找到血氧。如果您超过 18 岁，请在(Blood Oxygen)健康档案(Health Profile)中设置您的年龄并再次检查血氧(Blood Oxygen)应用程序。
点击“摘要”选项卡中的个人资料图标，选择“(profile icon)健康详情(Health Details)” ，点击“编辑(Edit)”，然后点击“出生(Birth)日期(Date)”行。输入正确的出生详细信息，然后点击完成(Done)。
关闭(Close)并重新打开Health应用程序，然后查看上面的step #3以启用血氧。
如何进行血氧测量(Blood Oxygen Measurement)
将Apple Watch(Apple Watch)戴在手腕上，确保表带紧实舒适。将Apple Watch移至手腕上方，使底座始终贴合您的皮肤。Apple建议将手表放置在距离腕骨 1-2 英寸的位置。
将手臂放在膝上、桌子或任何稳定的表面上，让Apple Watch朝上并保持静止。
- 按下数字表冠(Digital Crown)打开手表的主屏幕，然后点击血氧应用程序(Blood Oxygen app)图标。
- 如果这是您第一次使用该应用程序，请点击下一步(Next)以阅读一些测量提示和指南。
- 点击开始(Start)进行血氧测量并保持手臂不动，直到应用程序完成 15 秒倒计时。您将在结果页面上看到您的血氧水平。
注意：(Note:) 血氧(Blood)水平或氧饱和度水平（缩写为SpO2）以百分比 (%) 测量。
轻敲手指或轻轻移动手会中断测量。如果应用程序在结果页面上显示“无法测量血氧水平”错误，请重新进行测试。(Blood)这一次，重新调整您的Apple Watch以使其适合，并将您的手臂保持在桌子上。
什么是“正常”血氧水平？
美国食品(Food)和药物管理局(Drug Administration)( FDA ) 将blood oxygen level for healthy individuals at 95% to 100%。但是，患有肺病和心脏病的人的血氧水平可能较低（80-90%）。
我们还应该提到，一些环境和物理因素会暂时降低您的血氧水平。例如，睡觉、屏住呼吸或在高海拔环境中（山上或飞机上）消磨时间会降低血氧。这是因为肺中的氧气量取决于时间、活动和地点。
健康(Health)应用中有一篇关于血氧(Blood Oxygen)的教育文章。阅读文章，了解血氧对您的健康的重要性。
打开 Health 应用程序，转至Browse > Respiratory > Blood Oxygen，然后点击Learn About Blood Oxygen Levels。
查看血氧读数
打开健康应用程序，点击所有健康数据(All Health Data)，然后选择血氧(Blood Oxygen)卡。您将在图表下方看到最新的血氧测量值。
或者，转到浏览(Browse)>呼吸(Respiratory)并点击最近的血氧(Blood Oxygen)测量。
向下滚动页面并点击显示所有数据(Show All Data)以查看所有带有日期和时间戳的测量值。
你应该相信 Apple Watch 的血氧测量(Blood Oxygen Measurement)吗？
你应该，但不是为了医疗目的。智能手表(Smartwatches)未经美国食品(Food)药品监督管理局(Drug Administration)( FDA ) 认证可测量血氧水平。此外，Apple Watch 传感器发出的彩色和红外LED灯不会穿透您的皮肤或血液。相反，传感器使用皮肤中的血液反射多少（红色）光来测量血氧。
环境或皮肤温度的变化会影响血氧(Blood Oxygen)应用程序的测量。因此，在寒冷中获得准确的血氧测量是非常渺茫的。纹身还会阻挡 Apple Watch 传感器发出的光线，导致测量失败。
一些报告证明，Apple Watch 上的血氧测量值不可靠(blood oxygen measurements on the Apple Watch are unreliable)，可能会产生误导。Apple还警告说， (Apple)Apple Watch的血氧测量不适合医疗用途。据Apple称，该功能仅为“一般健身和保健目的”而设计。
医院使用的经 FDA 批准的处方血氧计可提供更准确的血氧测量。非处方 ( OTC ) 血氧计可以提供近乎准确的血氧饱和度估计值，但它们未经 FDA 认证，不能用于临床目的。
抽血测试仍然是确定血氧水平的最佳和最准确的方法。如果您有任何需要测量血氧的严重疾病，请勿使用Apple Watch。相反，请咨询医生或前往医学实验室进行抽血和测试。
How to Use Apple Watch’s Blood Oxygen Sensor
Blood oxygen measurement іs the flagship health-related feature of the new generation of Apple Watch models. It’s an estimation of how much oxygen your red blood cells transport from your lungs to other body parts.
This blog post will explain how the Apple Watch Blood Oxygen sensor measures your blood oxygen level. Additionally, you’ll learn how to set up the Blood Oxygen app on your new Apple Watch and iPhone.
How Apple Watch Measures Your Blood Oxygen
The Apple Watch Series 4, Series 5, Series 6, and Series 7 have optical heart sensors that measure heart rate. However, the heart sensors on the Apple Watch Series 6 and Series 7—and possibly newer models—can measure both heart rates and blood oxygen level (also called oxygen saturation level).
When measuring blood oxygen, your Apple Watch shines bright red and green LED lights and infrared light onto your wrist. Blood reflects red, so the Photodiode sensors measure the amount of red light the blood in your skin reflects.
That’s how the Apple Watch Series 6 and Series 7 determine how oxygen-rich your blood is. Typically, the more red light your blood reflects, the higher your blood oxygen.
How to Set Up Apple Watch’s Blood Oxygen Feature
Blood oxygen measurement is disabled by default on compatible Apple Watch models. To use the feature, enable Blood Oxygen measurement on your Apple Watch. Then, configure the iPhone Health app to receive blood oxygen data from your Apple Watch.
Set Up the Blood Oxygen App
Enabling blood oxygen measurement in your Apple Watch settings activates the Blood Oxygen app.
Open the Settings app on your Apple Watch, tap Blood Oxygen, and toggle on Blood Oxygen Measurements.
Alternatively, you can remotely set up Apple Watch Blood Oxygen from the Watch app on your iPhone. Open the Watch app, go to My Watch > Blood Oxygen, and turn on Blood Oxygen Measurements. Afterward, select if you want the Blood Oxygen app to take background measurements in theater and sleep mode.
Note: You won’t find Blood Oxygen on your Apple Watch if the service isn’t available in your country or region. Change your App Store country if you can’t wait until Apple rolls out the app to your country. Visit this watchOS feature availability page to view countries that can use the Blood Oxygen app.
Set Up Blood Oxygen Measurement in the Health App
Blood oxygen measurements from your Apple Watch are recorded in the Health app on your iPhone. After enabling Blood Oxygen Measurements on your Apple Watch, follow these steps to enable Blood Oxygen in the Health app:
- Open the Health app on your iPhone, enter personal health details, and tap Done to set up your Health Profile.
- The Health app should display a prompt to enable Blood Oxygen if your Apple Watch and iPhone are connected. Tap Enable to continue.
- If you don’t get this prompt, head to the Browse tab, tap Respiratory, select Blood Oxygen, and tap Enable. Then, proceed to the next section to take your first blood oxygen measurement.
Can’t find Blood Oxygen in the Health app? Update your Apple Watch and iPhone to the latest version of watchOS and iOS, respectively.
We should mention that Blood Oxygen measurement is only available for users aged 18 years and older. You won’t find Blood Oxygen in the Health app if the age in your Health Profile is below 18. If you’re over 18, set up your age in the Health Profile and check for the Blood Oxygen app again.
Tap the profile icon in the “Summary” tab, select Health Details, tap Edit, and tap the Date of Birth row. Enter your correct birth details and tap Done.
Close and reopen the Health app and see step #3 above to enable Blood Oxygen.
How to Take Blood Oxygen Measurement
Wear your Apple Watch on your wrist and ensure the watch band has a tight but comfortable fit. Move your Apple Watch above your wrist so that the base sits on your skin all the time. Apple recommends positioning your watch 1-2-inches away from your wrist bone.
Rest your arm (on your lap, table, or any stable surface), keep your Apple Watch facing up, and stay still.
- Press the Digital Crown to open your watch’s home screen and tap the Blood Oxygen app icon.
- If it’s your first time using the app, tap Next to read some measurement tips and guidelines.
- Tap Start to take the blood oxygen measurement and keep your arm still until the app completes the 15 seconds countdown. You’ll see your blood oxygen level on the results page.
Note: Blood oxygen level or oxygen saturation level (abbreviated SpO2) is measured in percentage (%).
Tapping your fingers or slightly moving your hands will interrupt the measurement. Retake the test if the app displays a “Blood oxygen levels could not be measured” error on the results page. This time, readjust your Apple Watch for a proper fit and keep your arm still on a table.
What’s the “Normal” Blood Oxygen Level?
The Food and Drug Administration (FDA) pegs the blood oxygen level for healthy individuals at 95% to 100%. However, people with lung and heart conditions may have low blood oxygen levels (80-90%).
We should also mention that some environmental and physical factors can temporarily drop your blood oxygen level. For instance, sleeping, holding your breath, or spending time in high-elevation environments (on mountains or airplanes) will reduce blood oxygen. That’s because the amount of oxygen in your lungs depends on time, activity, and places.
There’s an educational article about Blood Oxygen in the Health app. Go through the article to learn about the significance of blood oxygen to your health.
Open the Health app, go to Browse > Respiratory > Blood Oxygen, and tap Learn About Blood Oxygen Levels.
View Blood Oxygen Readings
Open the Health app, tap All Health Data, and select the Blood Oxygen card. You’ll see the latest blood oxygen measurement below the graph.
Alternatively, go to Browse > Respiratory and tap the recent Blood Oxygen measurement.
Scroll down the page and tap Show All Data to view all measurements with date and timestamps.
Should You Trust Apple Watch’s Blood Oxygen Measurement?
You should, but not for medical purposes. Smartwatches aren’t certified by the Food and Drug Administration (FDA) to measure blood oxygen levels. Besides, the colored and infrared LED lights from your Apple Watch’s sensors don’t penetrate your skin or blood. Instead, the sensor measures blood oxygen using how much (red) light the blood in your skin reflects.
Changes in environmental or skin temperature can impact the measurement of the Blood Oxygen app. Therefore, getting an accurate blood oxygen measurement in the cold is very slim. Tattoos can also block the light from your Apple Watch’s sensors and cause unsuccessful measurements.
Some reports prove that blood oxygen measurements on the Apple Watch are unreliable and could be misleading. Apple also warns that blood oxygen measurements from your Apple Watch aren’t intended for medical use. The feature, according to Apple, is designed for “general fitness and wellness purposes” only.
FDA-approved prescription oximeters used in hospitals provide more accurate blood oxygen measurements. Over-the-counter (OTC) oximeters may provide near-accurate blood oxygen saturation estimates, but they aren’t FDA-certified and cannot be used for clinical purposes.
A blood draw test remains the best and most accurate method to determine your blood oxygen level. If you have any serious medical condition requiring blood oxygen measurement, don’t use an Apple Watch. Instead, speak to a doctor or visit a medical lab to have your blood drawn and tested.
