Patent ID: 7635337
Filing Date: 2009-12-22
Classification: A61B

Abstract:
1. A method for determining clinical stress of a subject, the method comprising the steps of: positioning a probe of a pulse oximeter on the subject; acquiring plethysmographic signal data from the pulse oximeter associated with a subject; deriving a first measurement signal in a control and processing unit, the first measurement signal being indicative of a predetermined feature of respiration modulation appearing in the plethysmographic signal data, wherein the deriving step includes deriving the first measurement signal indicative of the predetermined feature, in which the predetermined feature is the respiration rate; forming an index signal in the control and processing unit based on the first measurement signal, wherein the forming step includes a sub-step of generating a second measurement signal indicative of variability in the first measurement signal; and employing the index signal as an index indicative of the clinical stress of the subject.