title: Continuous wireless pressure monitoring and mapping with ultra-small passive sensors for health monitoring and critical care.
abstract: Continuous monitoring of internal physiological parameters is essential for critical care patients, but currently can only be practically achieved via tethered solutions. Here we report a wireless, real-time pressure monitoring system with passive, flexible, millimetre-scale sensors, scaled down to unprecedented dimensions of 1 × 1 × 0.1 cubic millimeters. This level of dimensional scaling is enabled by novel sensor design and detection schemes, which overcome the operating frequency limits of traditional strategies and exhibit insensitivity to lossy tissue environments. We demonstrate the use of this system to capture human pulse waveforms wirelessly in real time as well as to monitor in vivo intracranial pressure continuously in proof-of-concept mice studies using sensors down to 2.5 × 2.5 × 0.1 cubic millimeters. We further introduce printable wireless sensor arrays and show their use in real-time spatial pressure mapping. Looking forward, this technology has broader applications in continuous wireless monitoring of multiple physiological parameters for biomedical research and patient care.
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA.
authors.forename: Lisa Y
authors.initials: LY
authors.lastname: Chen
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA.
authors.forename: Benjamin C-K
authors.initials: BC
authors.lastname: Tee
authors.affiliation: Department of Materials Science and Engineering, Stanford University, Stanford, California 94305, USA.
authors.forename: Alex L
authors.initials: AL
authors.lastname: Chortos
authors.affiliation: Department of Chemical Engineering, Stanford University, 381 North South Mall, Stanford, California 94305, USA.
authors.forename: Gregor
authors.initials: G
authors.lastname: Schwartz
authors.affiliation: 1] Department of Neurosurgery, Kaiser Permanente, Redwood City, California 94063, USA [2] Department of Neurosurgery, Stanford University, Stanford, California 94305, USA.
authors.forename: Victor
authors.initials: V
authors.lastname: Tse
authors.affiliation: Department of Chemical Engineering, Stanford University, 381 North South Mall, Stanford, California 94305, USA.
authors.forename: Darren J
authors.initials: DJ
authors.lastname: Lipomi
authors.affiliation: Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA.
authors.forename: H-S Philip
authors.initials: HS
authors.lastname: Wong
authors.affiliation: 1] Department of Electrical Engineering, Stanford University, Stanford, California 94305, USA [2] Division of Cardiovascular Medicine, Stanford University, Stanford, California 94305, USA.
authors.forename: Michael V
authors.initials: MV
authors.lastname: McConnell
authors.affiliation: Department of Chemical Engineering, Stanford University, 381 North South Mall, Stanford, California 94305, USA.
authors.forename: Zhenan
authors.initials: Z
authors.lastname: Bao
mesh_terms: D000818:Animals; D002138:Calibration; D003422:Critical Care / Q000379:methods*; D060733:Electromagnetic Radiation; D004867:Equipment Design; D006801:Humans; D008297:Male; D008422:Materials Testing; D051379:Mice; D008810:Mice, Inbred C57BL; D008991:Monitoring, Physiologic / Q000379:methods*; D011312:Pressure; D059015:Wireless Technology