果冻传媒

Out-of-hospital cardiac arrest (OHCA) is a major health problem and occurs in individuals of all
ages, women and men, ethnicities and socioeconomic positions. The incidence of OHCA is
approximately 17.000 per year in the Netherlands. All currently available systems to rescue OHCA
victims depend on witnesses who act as the first step in the Chain of Survival by alerting dispatch
centres and/or performing resuscitation and defibrillation with an automated external defibrillator
(AED). At present, however, more than half of OHCA cases is unwitnessed and these victims have
virtually no chance of survival.
Technology to detect OHCA, that can be worn permanently and that automatically alerts dispatch
centres could save the lives of many unwitnessed OHCA victims and improve quality of life. This
technology is therefore urgently needed. Moreover, the technology might also improve outcomes
in witnessed OHCA situations as the chain of rescue is initiated earlier.
Our proposal targets the development of a wearable monitoring platform that enables automatic
detection of OHCA and alerting of bystanders and dispatch centres. Key requirements of our
proposed platform are 1) that it enables 24/7 monitoring of OHCA in a wide and diverse population;
and 2) that it has high accuracy in the detection of OHCA.
A key enabler of the first requirement is that our solution is unobtrusive, not only from the physical
point of view but also from the psychological point of view. To achieve this level of unobtrusiveness,
our platform will build on an existing remote patient monitoring platform in the shape of a wristworn
device (smartwatch) that measures motion and pulsatile blood flow via accelerometry
and photoplethysmography (PPG) sensors, respectively.
As key enabler for the second requirement, cessation of the pulsatile blood flow in the wrist, which
happens in case of OHCA, will be detected from the PPG. Additionally, lack of movement, which
happens because OHCA victims lose consciousness immediately, will be detected from the
accelerometers. By combining the absence of pulsatile blood flow with absence of movement and
a failure to respond to stimuli, our solution will yield the required high accuracy in detection of
OHCA and will trigger early alarms to emergency responders, for the first time providing reliable
technological means to save lives of victims of unwitnessed cardiac arrest.