How it works: Biobeat has several devices and systems available, but this overview focuses on the "Hospital at Home" option with continuous monitoring. The user (patient) downloads the app on their phone and connects the watch, which has a proprietary PPG sensor in it that derives multiple types of vital sign data. Regarding the measurement of many of these vital signs, the watch has been FDA-approved for accuracy. The app sends the data to the Biobeat system, which does further calculations and analysis to produce a dashboard of vitals. This dashboard also shows an "Early Warning Score", which is an AI-derived number representing the likelihood of patient decline. A nurse has to periodically check the dashboard and will see notification alerts on the screen if an issue is detected. The system explicitly states that it is not meant for patients in critical care and is instead meant for patients who are stable and sent home from the hospital but still may run into issues.
High-level summary of issues: Biobeat Monitoring System
Before getting into the issues, I think it's worth acknowledging that it appears Biobeat has moved the needle significantly in terms of what is possible with light-based wrist sensors. Using a proprietary sensor (and newly developed algorithms) they have managed to measure blood pressure on the wrist accurately enough that they have gained FDA approval. They also measure blood saturation, stroke volume, pulse rate, systemic vascular resistance, mean arterial pressure, and cardiac output. Learn more about the Biobeat system here.
The issues with using the Biobeat system for cryonics monitoring can be divided into two categories: issues of access and issues of suitability. The first regards the lack of access to this device outside of a medical setting (e.g., monitoring nurse). The second refers to it's lack of an actual "alarm" system in place as well as questions regarding the behavior of the system in the case of sudden death. I'll go into these in turn.
When I say this system has lack of access, I mean that the company will not sell it for use in a non-medical context, which they define as a medical setting involving patients, nurses, and doctors. Whether this is due to liability concerns, legal (FDA) concerns, or a mix of both is not clear. It may be that Alcor could qualify for purchase and use of this system, but then what? Then we encounter the second kind of issue, that of suitability. As mentioned, the device does not yet have an alarm system in place; instead, a nurse at a nurse station periodically checks an application that will have notifications if a patient may be declining. Since the device not meant for critical patients that should be in a hospital, it's not designed to intervene in emergencies. Rather, it's meant to detect deterioration early, allowing the doctor to evaluate if the patient should be re-admitted.
For cryonics purposes, early detection would be great, even if it didn't catch all early signs all the time. The other issue that arises is the usual issue of sensor calibration not being effective below 20 bpm (beats per minute), meaning it's an open question what PPG data emerges in the state of having no pulse. I have had several personal, at-length communications with a Biobeat representative to try and get some idea of what happens in the case of sudden death. He never commented on that, indicating "our system is not intended for that use".
There may be ways around this. In my discussions with Biobeat, I learned that they will grant access to some of the data coming from the watch to the server and already have clients building custom features this way. It's also possible to automate the 'nurse' role of checking each patient profile for important notifications using robotic process automation software such as UiPath. This would allow us to write custom escalation (e.g., calling contacts) that would run without the need for a person to check each profile.
Alas, the uncertainty around behavior when pulse is 0 bpm in combination with access issues put a damper on the enthusiasm for me personally. It's also expensive to try (around $1800 per device). I don't have a device, and therefore further evaluation of Biobeat's system is sitting on the sidelines for now, though I do think this could be a promising system for cryonics.
Summary: The Biobeat system has a lot of strong points, including a proprietary PPG sensor that performs better than others on the market and FDA approval for uncommon wrist-based measurements, such as light-based blood pressure. However, their devices cannot simply be purchased and used as a cryonics alarm. Access to their system is granted only when used in a medical setting. Moreover, out of the box, it does not have an emergency alerting system. While this limitation could be worked around in various ways with development work done on top of Biobeat's system to adjust it to our needs, this remains out of reach to our team at Cryonics Monitoring, hindering further evaluation.
