Hospital patients are often covered in wires, with these attachments rendering them much more incapable and immobile than they would otherwise be. That can work to the detriment of their own care--as well as require routine and costly assistance from nurses and assistants.
Several companies are working to free vital sign monitoring from these constraints in the hospital, institutional or even the home setting. The latest news on this front comes from Royal Philips ($PHG), which recently published data on the effective monitoring of the absolute oxygen saturation of arterial blood.
The accurate detection of this commonly monitored vital sign without individualized calibration could lead to a contactless monitoring solution that also effectively measures several key vital signs such as SpO2, as well as heart rate and respiration rate.
"Vital signs monitoring is crucial across all types of care settings, but for patient populations with specific conditions, managing their care in a less intrusive way is critical in order to avoid unnecessary distress," said Carla Kriwet, CEO of Philips Patient Care & Monitoring Solutions, in a statement. "Contactless monitoring solutions will offer clinicians with a way to accurately measure vital signs for patients in a non-obtrusive way, and provide them with the data needed to know when to intervene."
The Philips technology can calculate an accurate pulse rate by tracking micro-blushes via changes in facial skin color.
In the camera-based pulse oximetry study published in the June issue of Anesthesia & Analgesia, 41 adults, including four with dark skin, were studied simultaneously with both that technology and standard contact probes in normal oxygen, low-oxygen and low-temperature environments.
The data found the camera-based technology offered accurate SpO2 data 83% to 100% of the time. The biggest challenges were presented by low signal strength and subject motion--which the researchers expect to have to address to make camera-based pulse oximetry practically feasible.
Philips is hardly alone in working on contactless monitoring. British camera-based vital sign monitoring startup Oxehealth recently secured a manufacturing deal with Samsung, while the Israeli contact-free, under-the-mattress vital sign monitor company EarlySense just nabbed a $25 million venture capital infusion--in addition to an existing roster of corporate partners that include Samsung, Welch Allyn and Mitsui. Other efforts also are examining the virtues of radar-based--or even ingestible--vital sign sensing.