Abstract: A method and system for detecting blood pressure pulses and screening out artifact-induced pulses when an automatic blood pressure monitor is provided. In preferred embodiments, the system detects the occurrence of an oscillometric pulse, determines the amplitude and rise time of the pulse, determines whether the amplitude and rise-times are within patient-specific screening limits and disregards pulses not within the limits, determines whether a pulse matches other pulses and saves the matching pulse data, determines the diastolic and systolic pressure based on the saved matched pulse data, and updates the patient-specific screening limits. In a preferred embodiment, pulses match based on similar amplitude and rise time characteristics. The amplitude and rise time screening limits are updated based on average values of prior blood pressure measurements for the patient.

Abstract: A blood pressure monitor capable of measuring blood pressure in the presence of artifact. One embodiment of the blood pressure monitor uses a detector to generate a trigger signal on the occurrence of the R-wave or other point on the ECG waveform. Oscillometric waveform samples taken at the same time after each trigger signal are then summed with each other over many heartbeats to generate an average oscillometric waveform that is used to determine blood pressure by conventional means. Another embodiment of the blood pressure monitor stores oscillometric waveform samples over many heartbeats. The monitor then assumes that the period of the heartbeat has a variety of durations, and it derives respective sets of composite samples by summing the stored samples having the same temporal relationship to the start of each assumed period. The set of composite samples corresponding the a waveform that best matches an actual oscillometric wave is then used to determine blood pressure by conventional means.

Abstract: A method and system for detecting blood pressure pulses and screening out artifact-induced pulses when an automatic blood pressure monitor is provided. In preferred embodiments, the system detects the occurrence of an oscillometric pulse, determines the amplitude and rise time of the pulse, determines whether the amplitude and rise-times are within patient-specific screening limits and disregards pulses not within the limits, determines whether a pulse matches other pulses and saves the matching pulse data, determines the diastolic and systolic pressure based on the saved matched pulse data, and updates the patient-specific screening limits. In a preferred embodiment, pulses match based on similar amplitude and rise time characteristics. The amplitude and rise time screening limits are updated based on average values of prior blood pressure measurements for the patient.

Abstract: A system for determining if a blood pressure measurement made by an automatic blood pressure monitor has been adversely affected by artifact. The system first compares the diastolic, mean arterial and systolic pressures to respective average diastolic, mean arterial and systolic pressures. If all three of these pressures are within a predetermined range of their corresponding average pressures and if the relationship between these pressures conforms to a physiologically realistic model, then the diastolic, mean arterial and systolic pressures obtained from a measurement are considered valid. If more than one of these pressures is outside the predetermined range of its corresponding average pressure, then the measurement is considered to be adversely affected by artifact and is rejected. If only one of these pressures is outside the predetermined range of its corresponding average pressure, then a replacement pressure is calculated for that pressure.

Abstract: A system for identifying artifact in automatic blood pressure measuring system. The system determines whether a single blood pressure signal, such as an oscillometric pulse or Korotkoff sound, occurs for each QRS complex of an ECG waveform in order to verify that the blood pressure signal is valid. In the event that multiple blood pressure signals occur between successive QRS complexes, at least some of the blood pressure signals are determined to be induced by artifact.

Abstract: A method and apparatus for determining the mean arterial pressure in an automatic blood pressure measuring system in which a table of data is obtained of cuff pressures and the amplitude of oscillometric pulses produced at each cuff pressure. The oscillometric pulses having the greatest amplitude and a reference cuff pressure at which such oscillometric pulses occurred are first identified from the table. Respective first and second cuff pressures that are above and below the reference cuff pressure and have a amplitude of 90% of the largest oscillometric pulses are then calculated by interpolating between the measured data in the table, and the mean arterial pressure is then calculated as the average of the first and second cuff pressures.