Apple has been working on a futuristic blood pressure device solution since at least 2018. Since then, Apple’s patents have shown us various approaches their research teams are taking from wrist devices to advanced blood pressure cuffs: 01 , 02 , 03 , 04 , 05 and more. Today the US Patent and Trademark Office published a patent application from Apple relating to systems and methods for non-invasively capturing and analyzing blood pressure measurement data.
In the background to Apple’s patent he notes that various non-invasive blood pressure measurement techniques are commonly used to determine a user’s blood pressure. Auscultation and oscillometry are popular methods of noninvasively measuring a user’s blood pressure due to their ease of use and ability to be performed in remote settings such as the user’s home. However, noninvasive blood pressure measurement methods, such as these, tend to have lower accuracy and/or greater variability than invasive measurement techniques such as direct intra-arterial sensing.
Apple’s invention covers a blood pressure measurement system for determining one or more blood pressure parameters of a user. Examples of blood pressure parameters may include systolic blood pressure, diastolic blood pressure, mean pressure, blood pressure variability, or other physiological parameters for the user.
The system may include a restriction device. which is configured to apply external pressure to the user to stop blood flow through one or more blood vessels of the user. In some cases, the external pressure cycle may be called an applied pressure sweep.
The restraint device may be an inflatable cuff, a band that can be tightened around the user’s limbs, or some other suitable device.
The system may also include a pressure sensing device configured to detect pressure changes within one or more blood vessels while an external pressure cycle is applied. For example, pressure changes may result in changes in the pulse pressure waveform within the user’s blood vessel as a result of an external pressure cycle. The system may analyze the pressure detected by the pressure sensing device to determine one or more blood pressure parameters for the user.
A non-invasive blood pressure measurement system and analysis technique that can more accurately and repeatedly determine one or more parameters of a user’s blood pressure.
The described blood pressure measurement system includes devices and analysis techniques that may result in more accurate and/or more repeatable non-invasive blood pressure measurements for the user. The system may include the use of a pressure sensing device that detects pressure within a user’s blood vessel while applying external pressure to the user to alter flow through the user’s blood vessel. In some cases, the pressure sensing device can be configured to detect the pressure of the pulse pressure waves that occur within the user’s blood vessels and output a signal of the pressure detected for the pulse pressure waves. she does. In this regard, output pressure includes data corresponding to changes in blood pressure that occur during each pulse pressure wave. Output detection pressure includes minimum pulse pressure, maximum pulse pressure, rate of pressure change, pressure change due to valve closure, pulse frequency, and/or other pulse pressure values. May include event related information.
Apple’s patent FIG. 1A below shows a block diagram of an example blood pressure management system. fig. 1B shows an example of a blood pressure measurement system worn by a user.
Apple’s patent FIG. 1C below shows an example of a blood pressure measurement system worn by a user in the form of an Apple Watch with a custom band. fig. 2 An example process flow chart for operating a blood pressure measurement system is:
Apple’s patent FIG. Figure 5 above is a flowchart illustrating the operation of determining a blood pressure parameter from a blood pressure measurement. And fig. 6B shows a sample set of blood pressure data used to determine a user’s blood pressure parameter.
For more details, review Apple’s patent application number US 20220400959 A1.
Inventor of Apple
- Rob Montgomery: Systems Engineer
- Chanhan Lin: Engineering Manager, Sensing Technology