Integrated monitoring and analysis for early warning of patient deterioration.
Recently there has been an upsurge of interest in strategies for detecting at-risk patients in order to trigger the timely intervention of a Medical Emergency Team (MET), also known as a Rapid Response Team (RRT). We review a real-time automated system, BioSign, which tracks patient status by combining information from vital signs monitored non-invasively on the general ward. BioSign fuses the vital signs in order to produce a single-parameter representation of patient status, the Patient Status Index. The data fusion method adopted in BioSign is a probabilistic model of normality in five dimensions, previously learnt from the vital sign data acquired from a representative sample of patients. BioSign alerts occur either when a single vital sign deviates by close to +/-3 standard deviations from its normal value or when two or more vital signs depart from normality, but by a smaller amount. In a trial with high-risk elective/emergency surgery or medical patients, BioSign alerts were generated, on average, every 8 hours; 95% of these were classified as 'True' by clinical experts. Retrospective analysis has also shown that the data fusion algorithm in BioSign is capable of detecting critical events in advance of single-channel alerts.
Tarassenko
L
L
Department of Engineering Science, Parks Road, University of Oxford, Oxford OX1 3PJ, UK. lionel.tarassenko@eng.ox.ac.uk
Hann
A
A
Young
D
D
D003422:Critical Care / Q000379:methods*; D006305:Health Status Indicators; D006801:Humans; D008991:Monitoring, Physiologic / Q000379:methods*; D010362:Patients' Rooms; D012815:Signal Processing, Computer-Assisted