Abstract: A non-invasive apparatus and method for monitoring the blood pressure of a subject detects a pulse signal at both a first and second location on the subject's body The elapsed time between the arrival of corresponding points of the pulse signal at the first and second locations is determined. Blood pressure is related to the elapsed time by relationships such as: P=a+b ln(T), where a and b are constants dependent upon the nature of the subject and the signal detecting devices.

Abstract: A method and apparatus for measuring blood pressure by the oscillometric technique. The method incorporates variable PIP's. The method comprises the steps of obtaining a value for the peak amplitude Amax of an oscillometric envelope; determining a cuff pressure, CP, which corresponds in time with Amax, this pressure representing the MAP of the subject; computing a variable value PIPSBP as a function of MAP; performing the calculation Asbp=Amax*PIPSBP to determine a systolic amplitude value Asbp along the oscillometric envelope; and determining the cuff pressure C which corresponds in time to Asbp, this value representing the systolic blood pressure (SBP) of the subject. PIP can be calculated using a piece-wise linear, polynomial, exponential or other function.

Abstract: A non-invasive apparatus and method for monitoring the blood pressure of a subject detects a pulse signal at both a first and second location on the subject's body The elapsed time between the arrival of corresponding points of the pulse signal at the first and second locations is determined.

Abstract: A non-invasive apparatus and method for monitoring the blood pressure of a subject detects a pulse signal at both a first and second location on the subject's body. The elapsed time between the arrival of corresponding points of the pulse signal at the first and second locations is determined. Blood pressure is related to the elapsed time by relationships such as: P=a+b ln(T) where a and b are constants dependent upon the nature of the subject and the signal detecting devices. The system can be calibrated by measuring a single pair of reference blood pressure and corresponding elapsed time.

Abstract: A method and apparatus for measuring blood pressure by the oscillometric technique. The method incorporates variable PIP's. The method comprises the steps of obtaining a value for the peak amplitude Amax of an oscillometric envelope; determining a cuff pressure, CP, which corresponds in time with Amax, this pressure representing the MAP of the subject; computing a variable value PIPSBP as a function of MAP; performing the calculation Asbp=Amax*PIPSBP to determine a systolic amplitude value Asbp along the oscillometric envelope; and determining the cuff pressure C which corresponds in time to Asbp, this value representing the systolic blood pressure (SBP) of the subject. PIP can be calculated using a piece-wise linear, polynomial, exponential or other function.

Abstract: Apparatus for monitoring one or more vital signs of a subject has a number of sensors. There is at least one redundant sensor. Each sensor originates a signal. A selection system determines performance criteria for a number of groups of signals. Each group includes one or more signals. The apparatus computes a predicted value for a vital sign by either computing a value from each group of signals and taking a weighted average with weights based upon the performance criterion or by selecting one of the groups of signals for which the performance criterion is best and computing the output value from that group of signals. The output values are relatively insensitive to artifacts and to errors caused by the disconnection or malfunctioning of one sensor.