Device for monitoring a vital sign

Abstract

A device ( 1 ) for monitoring a vital sign of a living subject, comprising a measuring unit ( 2 ) for measuring at least one physical quantity indicative of said vital sign at an area ( 8 ) overlying an artery ( 7 ) of the subject, which measuring unit ( 2 ) is provided on a carrier ( 3 ) to be worn by the subject during operation, and a processing unit ( 4 ) for processing the measured physical quantity into a value for the vital sign, which device ( 1 ) is provided with at least one detector ( 5 ) for detecting the position of the measuring unit ( 2 ) relative to the artery ( 7 ) of the subject during operation and for actuating a feedback signal (Ufeedback) in dependence on this position. The user can move the device ( 1 ) relative to the artery ( 7 ) until the feedback signal (Ufeedback) is given, and thus a correct positioning of the measuring unit ( 2 ) relative to the artery ( 7 ) is achieved in an easy manner.

1 . A device ( 1 ) for monitoring a vital sign of a living subject, comprising 
 a measuring unit ( 2 ) for measuring at least one physical quantity indicative of said vital sign at an area ( 8 ) overlying an artery ( 7 ) of the subject, which measuring unit ( 2 ) is provided on a carrier ( 3 ) to be worn by the subject during operation, and    a processing unit ( 4 ) for processing the measured physical quantity into a value for the vital sign, characterized in that the device ( 1 ) is provided with at least one detector ( 5 ) for detecting the position of the measuring unit ( 2 ) relative to the artery ( 7 ) of the subject during operation and for actuating a feedback signal (Ufeedback) in dependence on this position.    
     
     
         2 . A device as claimed in  claim 1 , characterized in that the detector ( 5 ) comprises at least one sensor for detecting the presence of the artery ( 7 ) in the vicinity of the sensor, which sensor is chosen from a group comprising electro-optical sensors and ultrasound sensors.  
     
     
         3 . A device as claimed in  claim 2 , characterized in that a plurality of sensors ( 10 ,  11 ) for detecting the presence of the artery ( 7 ) in the vicinity of the sensor ( 10 ,  11 ) are provided in an array.  
     
     
         4 . A device as claimed in  claim 1 , characterized in that the feedback signal (Ufeedback) is chosen from a group comprising audio and visual signs.  
     
     
         5 . A device as claimed in  claim 1 , characterized in that the carrier ( 3 ) comprises an annular body ( 3 ′) which is at least partly rigid.  
     
     
         6 . A device as claimed in  claim 1 , characterized in that the carrier ( 3 ) comprises an annular body ( 3 ″) which is entirely rigid.  
     
     
         7 . A device as claimed in  claim 1 , characterized in that the measuring unit ( 2 ′) comprises an inflatable cushion ( 13 ) for applying a pressure to said area ( 8 ) overlying said artery ( 7 ) of the subject, and the cushion ( 13 ) comprises a plurality of separately inflatable cushion parts ( 14 ).  
     
     
         8 . A device as claimed in  claim 8 , characterized in that the cushion parts ( 14 ) comprise protuberances ( 24 ) which project from a surface area ( 15 ) of the carrier ( 3 ) in a direction practically perpendicular to said surface area.  
     
     
         9 . A device as claimed in  claim 8  or  9 , characterized in that the carrier ( 3 ) comprises an annular body ( 16 ) which can be closed during operation, the cushion ( 13 ′) being provided along an entire inner wall of said body ( 16 ).